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https://forum.allaboutcircuits.com/threads/current-and-voltage-source.5128/#post-65394	Current and voltage source jasonhaykin Joined Mar 8, 2007 23 Hi guys, what is a current source ? if someone says a supply of 5A , what do they mean ? does current source have a voltage rating also ? Thanks beenthere Joined Apr 20, 2004 15,819 The basic electronic formula, E = IR, says it must. E is voltage, I is current, R is resistance. The 5 amp rating means thar the regulator can supply up to 5 amps current before the output voltage sags or the ripple increases beyond spec. tiger_prodigy Joined Mar 10, 2007 2 just a thought but is a current source the same as a voltage source except that it provides a constant current value and a adjustable voltage source as to allow for a higher amount of watts to be drawn on? form the formula W=EI and so when some one says 5A source does that not mean that you have a constant supply of 5A but a varying voltage value according to the amount of watts demanded by the circuit? Please correct me f I'm wrong thanks. beenthere Joined Apr 20, 2004 15,819 Most power supplies work in the volltage mode, so they maintain a constant voltage despite a varying load. Some have a current regulation mode where the voltage changes to maintain a constant current. It's easier maintaining a constant voltage, unless the amperage limit is exceeded. Constant surrent is not possible when the load gets too resistive - not enough voltage to push the current. And there is also the limit to the amount of current that can be supplied. awright Joined Jul 5, 2006 91 Current sources and voltage sources are exact analogues of each other and they each have their appropriate applications. We are most familiar with voltage sources as power supplies for most applications. A VOLTAGE SOURCE such as a common bench power supply or a battery ideally provides a fixed voltage independent of the amount of current required to maintain the fixed voltage. It appears to the load to have a ZERO SOURCE RESISTANCE. That is, viewing the junction of the voltage source output and the load input as the center point of a two-resistor voltage divider fed from an infinitely stiff, fixed voltage source, if the top (source) resistor is zero, the voltage at the junction ramains fixed for any value of the lower (load) resistance other than zero. Of course, the whole analogy breaks down at the value of load resistance to which the source cannot supply enough current. That point would be the knee of the voltage/current curve of the supply. Any voltage source will have some rated maximum current it can supply before voltage deviates more than some specified amount from the set voltage. The degree to which the voltage source deviates from zero source resistance is the degree to which it deviates from perfection, as all real devices must. On a voltage/current graph, the ideal voltage source would have a straight, horizontal line out to the point at wihich it cannot supply any more current and would then have a vertical line down to zero volts at its limiting current. In real life, the horizontal region slopes slightly or dramatically out to a sharp or very gradual knee (or burnout), followed by a steep or gradual slope down to zero volts. A CURRENT SOURCE ideally supplies a fixed current independent of the voltage required to maintain that current. It appears to the load ideally to have an INFINITE SOURCE RESISTANCE supplied by an infinite voltage (neither being actually true). A current source will have a voltage compliance specification, that is, some voltage at which it can no longer maintain the desired current within some specified accuracy. Note the inverse analogy with a voltage source. Viewed as a two-resistor voltage divider supplied by a quasi-infinite voltage, if the upper resistor is extremely large (approaching infinite) then the value of the lower (load) resistor will have no influence on the total current flowing and the voltage at the junction will vary in exact proportion to the load resistance. This is a current source. Both devices are imperfect, the degree of imperfection depending upon the intended application, the quality of the design, and where in the range of capabilities of the source you are operating, among many other factors. A voltage (vertical axis) vs. current (horizontal axis) graph of the output of the two types of sources would be a straight horizontal line for a perfect voltage source and a straight, vertical line for a perfect current source. Many modern bench power supplies can be set up by the user for either constant voltage or constant current function by proper use of the voltage limit and current limit knobs. A common application of a current source that you use every day would be a battery charger that limits the initial charging current to some safe value specified by the battery manufacturer. Another is as the "long tail" of a differential amplifier stage. Schematic diagrams will show such "long tailed" configurations in one or more stages of an operational amplifier IC and in many audio power amplifiers. In real applications, of course, there is no infinite resistance or infinite voltage supply - it is all simulated with active electronics. Take a look at the schematic of an op amp and look for two mirror-imaged transistors and notice how the emitters are connected directly or via a low resistance. The circuit below those connected emitters is a constant current source. Another common application of current sources is in circuits powering resistance strain gauges. If the simulated source resistance appears to be high enough, the output voltage from the strain gauge will be directly proportional to the resistance of the gauge and, therefore, the amount of strain. Hope this is interesting to you. awright jasonhaykin Joined Mar 8, 2007 23 thanks , this is very interesting . solarnovice Joined Apr 12, 2008 3 i wondered if I could deviate slightly with my question for a home-made solar charger... Say you have a solar panel putting out 15V 100MilliAmp giving 1.5Watt power rating. hope my numbers are right. Now most USB devices require a 5 to 5.3V supply (max 500ma) to charge up. So i looked around and found it was easy enough to limit the voltage to 5.3V. But the thing that is bothering me is that the extra volts were dissipated via resistor into heat. Could there be a way to use those extra volts to push up the amps put out by the circuit instead? I mean, the solar panel produces the extra volts but not the amps. Further, if I attached a device that required more amps than the solar panel can generate, what will be the effect ? my name says it all - i am a novice to this subject. could be i am no novice in others! Thanks for any suggestions/clarifications. Joined Apr 16, 2008 1 Very Thanx Caveman Joined Apr 15, 2008 471 solarnovice, Shoulda been a new post, not a thread hijack, but since you asked... What you want is a switching power supply. It is able to convert high voltages at lower currents to lower voltages at higher currents (minus some efficiency loss, which becomes heat). If you want to do it really simply, look into the TI PTH08080W. It costs a bit more (\$8.60), but it can be done. If you want to do it cheaper, you will have to learn a lot more. Oh and read the entire datasheet. These kinds of things require attention to detail.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8393985629081726, "perplexity": 919.7319145447809}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323585178.60/warc/CC-MAIN-20211017144318-20211017174318-00291.warc.gz"}
https://astarmathsandphysics.com/university-maths-notes/vector-calculus/4066-a-vector-field-giving-rise-to-a-function-defining-the-field.html	## A Vector Field Giving Rise to a Function Defining the Field Theorem Let $\mathbf{F}$ defined in a polygon ally connected open set $B \subset \mathbb{R}^n$ . If the line integral $\int_C \mathbf{F} \cdot d \mathbf{r}$ is independent of the path in $B$ from $x_0$ to $x$ then the function $f(x) = \int_{\mathbf{x_0}}^{\mathbf{x}} \mathbf{F} \cdot d \mathbf{x}$ is continuously differentiable and throughout $B$ the relationship $\mathbf{F}= grad \: f$ is satisfied. Proof Since $x \in B \subset \mathbb{R}^n$ and $B$ us open there exists an open ball $B(x, \delta ) \subset B$ $\delta$ with centre $x$ For all real numbers $\| \alpha \| < \delta$ and unit vector $\mathbf{u}$ , $x+ \alpha \mathbf{u} \in B$ The line integral $\int_C \mathbf{F} \cdot d \mathbf{x}$ is independent of the path so we can choose any piecewise smooth curve in $B$ from $x_0$ to $x$ and extend it to $\mathbf{x} + \alpha \mathbf{u}$ by a linear segment. \begin{aligned} f(\mathbf{x} + \alpha \mathbf{u} )- f(\mathbf{x}) &= \int^{\mathbf{x} + \alpha \mathbf{u}}_{\mathbf{x_0}} \mathbf{F} \cdot d \mathbf{x} - \int^{\mathbf{x}}_{\mathbf{x_0}} \mathbf{F} \cdot d \mathbf{x} \\ &= \int^{\mathbf{x} + \alpha \mathbf{u}}_{\mathbf{x}} \mathbf{F} \cdot d \mathbf{x} \\ &= \int^{\alpha}_{0} \mathbf{F}( \mathbf{x}+ \beta \mathbf{u} ) \cdot \mathbf{u} d \beta \end{aligned} If $\mathbf{u}= \mathbf{e_k}$ is a base vector in $\mathbb{R}^n$ then \begin{aligned} \frac{\partial f}{\partial x_k} (\mathbf{x}) &= lim_{\alpha \rightarrow 0} \frac{f(\mathbf{x} + \alpha \mathbf{u}) - f (\mathbf{x})}{\alpha} \\ &= lim_{\alpha \rightarrow 0} \frac{1}{\alpha} \int^{\alpha}_0 \mathbf{F} ( \mathbf{x} + \beta \mathbf{e_k} ) \cdot \mathbf{e_k} d \beta \\ &= \frac{d}{d \alpha} \int^{\alpha}_0 \mathbf{F} ( \mathbf{x} + \beta \mathbf{e_k} ) \cdot \mathbf{e_k} d \beta \|_{\alpha =0} \\ &= \mathbf{F}( \mathbf{x}) \cdot \mathbf{e_k }) \\ &= F_k ( \mathbf{x}) \end{aligned} Since $\mathbf{F}$ is differentiable, the partial derivatives are continuous, Hence $\mathbf{F} = grad \: f$	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 2, "x-ck12": 0, "texerror": 0, "math_score": 1.0000100135803223, "perplexity": 6874.809840889366}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-05/segments/1516084889325.32/warc/CC-MAIN-20180120043530-20180120063530-00270.warc.gz"}
http://math.stackexchange.com/questions/116716/is-the-pythagorean-closure-of-mathbb-q-equal-to-the-field-of-constructible-nu	# Is the Pythagorean closure of $\mathbb Q$ equal to the field of constructible numbers? A Pythagorean field is one in which every sum of two squares is again a square. $\mathbb Q$ is not Pythagorean, which is easy to see. I have read a theorem online which says that every field has a unique (up to isomorphism) Pythagorean closure. I haven't found the proof so I thought I should start with the most familiar field, $\mathbb Q$. I was thinking if it would be possible to somehow imagine or characterize the Pythagorean closure $\mathbb P$ of $\mathbb Q.$ I know that in the field $\mathbb E$ of all constructible numbers, every positive number is a square because it is possible to construct square roots of already constructed numbers (by drawing a certain right triangle and its altitude). So $\mathbb E$ must be Pythagorean. $(1)$ But is it equal to $\mathbb P?$ If it's not, then what is the $\mathbb P$-dimension of $\mathbb E$? Surely, for any $q_1,q_2,\ldots,q_n\in \mathbb Q,$ we must have $\sqrt{q_1^2+q_2^2+\cdots + q_n^2}\in \mathbb P$ by a simple induction. $(2)$ Is this all we have to adjoin to $\mathbb Q$ to obtain $\mathbb P?$ It looks like it is but I haven't done anything with infinite extensions and I don't know how to handle this. - I imagine "unique Pythagorean closure" could mean unique up to isomorphism. This leaves a question of whether two distinct but isomorphic subfields of $\mathbb{R}$ could be Pythagorean closures of $\mathbb{Q}$. But certainly there's one that you get just by closing under the usual field operations and taking square roots. – Michael Hardy Mar 5 '12 at 18:25 @CamMcLeman I'm looking for a basis. I think the two equations I wrote down may be helpful in finding it because they give a way to think about less complicated expressions. – user23211 Mar 5 '12 at 22:05 @CamMcLeman Could you please comment here? I think if I reply here it will create a mess. – user23211 Mar 5 '12 at 22:13 @ymar: Already each non-negative rational is the sum of four squares of rationals, so the $n$ above need not be large! – André Nicolas Mar 5 '12 at 22:31 @ymar: Look at $a/b=ab/b^2$. Express $ab$ as the sum of the squares of the integers $s$, $t$, $u$, $v$. Then $a/b=(s/b)^2+(t/b)^2+(u/b)^2+(v/b)^2$. – André Nicolas Mar 5 '12 at 23:01 No, the two fields are not the same: It is a result of Hilbert that the Pythagorean field is the maximal totally real subfield of the field of constructible numbers. So any constructible number which is not totally real (i.e., its minimal polynomial has complex roots) gives a non-Pythagorean Euclidean number. An easy example is $\sqrt{1+\sqrt{2}}$ (with non-real conjugate $\sqrt{1-\sqrt{2}}$). Generalizing this example, it's easy to see that $\mathbb{E}$ is infinite-dimensional over $\mathbb{P}$. I believe your second question is answer in the affirmative by using that $\mathbb{P}$ is the smallest subfield of the Euclidean numbers closed under the operation of $x\rightarrow \sqrt{1+x^2}$, and inducting on the number of such operations you'd have to apply. I'd take a look at Roger Alperin's series of papers on trisections and origami for a good discussion of the fields in question (and others!). - Thank you very much. Could you please take a look at my edited question? – user23211 Mar 5 '12 at 21:51 @ymar: You're welcome! Though I think it makes more sense to ask a separate follow-up question than to append to the current one (to avoid confusion about which answers are answering which parts). In any case, I agree that it's clear that $(\mathbb{P}:\mathbb{Q})$ is infinite. – Cam McLeman Mar 5 '12 at 21:59 OK, I'll cut-paste this to a new question. – user23211 Mar 5 '12 at 22:07 I treat the concept of Pythagorean closure in these notes. In fact, I speak briefly about a class of fields being "closable" and give the Pythagorean closure as an example of that. Let $F$ be a field. Here are two key (but easy) observations: (CC1) Any algebraically closed field extension of $F$ is Pythagorean. (CC2) If $\{K_i\}_{i \in I}$ is a family of Pythagorean field extensions of $F$ -- all contained in some large field $L$ -- then also $K = \bigcap_{i \in I} K_i$ is a Pythagorean field extension of $F$. It follows that inside any algebraic closure $\overline{F}$ of $F$ there is a literally unique Pythagorean closure: the intersection of all Pythagorean algebraic extensions of $F$. (When $F = \mathbb{Q}$, Cam McLeman has given a spot-on description of it.) - They seem to be fantastic notes. I love that you included references. I've never seen lecture notes with references before! I will try to read them, but I may have to return to them later when I learn more about field theory. – user23211 Mar 7 '12 at 16:52 @ymar: thanks. Actually they are not really lecture notes in the sense that I have not (at least not yet) taught any corresponding course. They are more like "study notes" for me and my students...hence the references. (Although I do try to include references in my lecture notes as well...) – Pete L. Clark Mar 7 '12 at 17:19 (Same as my answer, but you explicitly treated uniqueness.) I might have written something like "If $\mathcal{K}$ is a family of Pythagorean field extensions of $F$ -- all contained in some large field $L$ -- then also $k=\bigcap\limits_{K\in\mathcal{K}} K$ is a Pythagorean field extension of $F$." Do the indices $i\in I$ add anything? – Michael Hardy Mar 8 '12 at 13:50 @Michael: Yes, my answer is quite similar to yours...but the uniqueness of the Pythagorean closure was explicitly part of the OP's question, so I felt it was worth it to nail down an answer to that. "Do the indices $i \in I$ add anything?" Not really, no. The way you might have written it seems just as good... – Pete L. Clark Mar 8 '12 at 13:58 When I think of the question of how to prove that every field has a unique Pythagorean closure, the first thing that comes to mind is that I might start with the fact that every field has a unique algebraic closure. Once you've got that, you wouldn't have to construct a field from scratch; you'd just look at the intersection of all subfields of the algebraic closure that include the field you started with and are closed under $(a,b)\mapsto\sqrt{a^2+b^2}$. The algebraic closure is closed under that operation, so you'd get something.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8396139740943909, "perplexity": 212.3667738259289}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-23/segments/1404776438333.54/warc/CC-MAIN-20140707234038-00021-ip-10-180-212-248.ec2.internal.warc.gz"}
https://www.arxiv-vanity.com/papers/1409.5335/	# Pimsner algebras and Gysin sequences from principal circle actions Francesca Arici, Jens Kaad, Giovanni Landi International School of Advanced Studies (SISSA), Via Bonomea 265, 34136 Trieste, Italy International School of Advanced Studies (SISSA), Via Bonomea 265, 34136 Trieste, Italy Matematica, Università di Trieste, Via A. Valerio 12/1, 34127 Trieste, Italy and INFN, Sezione di Trieste, Trieste, Italy , , v1 September 2014; v2 February 2015 ###### Abstract. A self Morita equivalence over an algebra , given by a -bimodule , is thought of as a line bundle over . The corresponding Pimsner algebra is then the total space algebra of a noncommutative principal circle bundle over . A natural Gysin-like sequence relates the -theories of and of . Interesting examples come from a quantum lens space over a quantum weighted projective line (with arbitrary weights). The -theory of these spaces is explicitly computed and natural generators are exhibited. ###### Key words and phrases: KK-theory, Pimsner algebras, Gysin sequences, circle actions, quantum principal bundles, quantum lens spaces, quantum weighted projective spaces. ###### 2010 Mathematics Subject Classification: 19K35, 55R25, 46L08, 58B32 Thanks. GL was partially supported by the Italian Project “Prin 2010-11 – Operator Algebras, Noncommutative Geometry and Applications”. ## 1. Introduction In the present paper we put in close relation two notions that seem to have touched each other only occasionally in the recent literature. These are the notion of a Pimsner (or Cuntz-Krieger-Pimsner) algebra on one hand and that of a noncommutative (in general) principal circle bundle on the other. At the -algebraic level one needs a self Morita equivalence of a -algebra , thus we look at a full Hilbert -module over together with an isomorphism of with the compacts on . Through a natural universal construction this data gives rise to a -algebra, the Pimsner algebra generated by . In the case where both and its Hilbert -module dual are finitely generated projective over one obtains that the -subalgebra generated by the elements of and becomes the total space of a noncommutative principal circle bundle with base space . At the purely algebraic level we start from a -graded -algebra which forms the total space of a quantum principal circle bundle with base space the -subalgebra of invariant elements and with a coaction of the Hopf algebra coming from the -grading. Provided that comes equipped with a -norm, which is compatible with the circle action likewise defined by the -grading, we show that the closure of has the structure of a Pimsner algebra. Indeed, the first spectral subspace is then finitely generated and projective over the algebra . The closure of will become a Hilbert -module over , the closure of , and the couple will lend itself to a Pimsner algebra construction. The commutative version of this part of our program was spelled out in [11, Prop. 5.8]. This amounts to showing that the continuous functions on the total space of a (compact) principal circle bundle can be described as a Pimsner algebra generated by a classical line bundle over the compact base space. With a Pimsner algebra there come two natural six term exact sequences in -theory, which relate the -theories of the Pimsner algebra with that of the -algebra of (the base space) scalars . The corresponding sequences in -theory are noncommutative analogues of the Gysin sequence which in the commutative case relates the -theories of the total space and of the base space. The classical cup product with the Euler-class is in the noncommutative setting replaced by a Kasparov product with the identity minus the generating Hilbert -module . Predecessors of these six term exact sequences are the Pimsner-Voiculescu six term exact sequences of [19] for crossed products by the integers. Interesting examples are quantum lens spaces over quantum weighted projective lines. The latter spaces are defined as fixed points of weighted circle actions on the quantum -sphere . On the other hand, quantum lens spaces are fixed points for the action of a finite cyclic group on . For general coprime positive integers and any positive integer , the coordinate algebra of the lens space is a quantum principal circle bundle over the corresponding coordinate algebra for the quantum weighted projective space, thus generalizing the cases studied in [5]. At the -algebra level the lens spaces are given as Pimsner algebras over the -algebra of the continuous functions over the weighted projective spaces (see §6). Using the associated exact sequences coming from the construction of [18], we explicitly compute in §7 the -theory of these spaces for general weights. A central character in this computation is played by an integer matrix whose entries are index pairings. These are in turn computed by pairing the corresponding Chern-Connes characters in cyclic theory. The computation of the -theory of our class of -deformed lens spaces is, to the best of our knowledge, a novel one. Also, it is worth emphasizing that the quantum lens spaces and weighted projective spaces are in general not -equivalent to their commutative counterparts. Pimsner algebras were introduced in [18]. This notion gives a unifying framework for a range of important -algebras including crossed products by the integers, Cuntz-Krieger algebras [9, 8], and -algebras associated to partial automorphisms [10]. Generalized crossed products, a notion which is somewhat easier to handle, were independently invented in [3]. More recently, Katsura has constructed Pimsner algebras for general -correspondences [15]. In the present paper we work in a simplified setting (see Assumption 2.1 below) which is close to the one of [3]. #### Acknowledgments We are very grateful to Georges Skandalis for many suggestions and to Ralf Meyer for useful discussions. We thank Tomasz Brzeziński for making us aware of the reference [17]. This paper was finished at the Hausdorff Research Institute for Mathematics in Bonn during the 2014 Trimester Program “Non-commutative Geometry and its Applications”. We thank the organizers of the Program for the kind invitation and all people at HIM for the nice hospitality. ## 2. Pimsner algebras We start by reviewing the construction of Pimsner algebras associated to Hilbert -modules as given in [18]. Rather than the full fledged generality we aim at a somewhat simplified version adapted to the context of the present paper, and motivated by our geometric intuition coming from principal circle bundles. Our reference for the theory of Hilbert -modules is [16]. Throughout this section will be a countably generated (right) Hilbert -module over a separable -algebra , with -valued (and right -linear) inner product denoted ; or simply to lighten notations. Also, is taken to be full, that is the ideal is dense in . Given two Hilbert -modules and over the same algebra , we denote by the space of bounded adjointable homomorphisms . For each of these there exists a homomorphism (the adjoint) with the property that for any and . Given any pair , an adjointable operator is defined by θξ,η(ζ)=ξ⟨η,ζ⟩,∀ζ∈E. The closed linear subspace of spanned by elements of the form as above is denoted , the space of compact homomorphisms. When , it results that is a -algebra with the (sub) -algebra of compact endomorphisms of . ### 2.1. The algebras and their universal properties On top of the above basic conditions, the following will remain in effect as well: ###### Assumption 2.1. There is a -homomorphism which induces an isomorphism . Next, let be the dual of (when viewed as a Hilbert -module): E∗:={ϕ∈HomB(E,B)\|∃ξ∈Ewithϕ(η)=⟨ξ,η⟩∀η∈E}. Thus, with , if is the operator defined by , for all , every element of is of the form for some . By its definition, . The dual can be given the structure of a (right) Hilbert -module over . Firstly, the right action of on is given by λξb:=λξ∘ϕ(b). Then, with operator for , the inner product on is given by ⟨λξ,λη⟩:=ϕ−1(θξ,η), and is full as well. With the -homomorphism defined by , the pair satisfies the conditions in Assumption 2.1. We need the interior tensor product of with itself over . As a first step, one constructs the quotient of the vector space tensor product by the ideal generated by elements of the form ξb⊗η−ξ⊗ϕ(b)η,forξ,η∈E,b∈B. (2.1) There is a natural structure of right module over with the action given by (ξ⊗η)b=ξ⊗(ηb),forξ,η∈E,b∈B, and a -valued inner product given, on simple tensors, by ⟨ξ1⊗η1,ξ2⊗η2⟩=⟨η1,ϕ(⟨ξ1,ξ2⟩)η2⟩ (2.2) and extended by linearity. The inner product is well defined and has all required properties; in particular, the null space is shown to coincide with the subspace generated by elements of the form in (2.1). One takes and defines to be the Hilbert module obtained by completing with respect to the norm induced by (2.2). The construction can be iterated and, for , we denote by , the -fold interior tensor power of over . Like-wise, denotes the -fold interior tensor power of over . To lighten notation, in the following we define, for each , the modules E(n):=⎧⎪⎨⎪⎩Eˆ⊗ϕnn>0Bn=0(E∗)ˆ⊗ϕ∗(−n)n<0. Clearly, and . We define the Hilbert -module over : E∞:=⨁n∈ZE(n). For each we have a bounded adjointable operator defined component-wise by Sξ(b) :=ξ⋅b, b∈B, Sξ(ξ1⊗⋯⊗ξn) :=ξ⊗ξ1⊗⋯⊗ξn, n>0, Sξ(λξ1⊗⋯⊗λξ−n) :=λξ2⋅ϕ−1(θξ1,ξ)⊗λξ3⊗⋯⊗λξ−n, n<0. In particular, . The adjoint of is easily found to be given by : Sλξ(b) :=λξ⋅b, b∈B, Sλξ(ξ1⊗…⊗ξn) :=ϕ(⟨ξ,ξ1⟩)(ξ2)⊗ξ3⊗…⊗ξn, n>0, Sλξ(λξ1⊗…⊗λξ−n) :=λξ⊗λξ1⊗…⊗λξ−n, n<0; and in particular . From its definition, each has a natural structure of Hilbert -module over and, with again denoting the Hilbert -module compacts, we have isomorphisms K(E(n),E(m))≃E(m−n). ###### Definition 2.2. The Pimsner algebra of the pair is the smallest -subalgebra of which contains the operators for all . The Pimsner algebra is denoted by with inclusion . There is an injective -homomorphism . This is induced by the injective -homomorphism defined component-wise by ϕ(b)(b′):=b⋅b′,ϕ(b)(ξ1⊗…⊗ξn):=ϕ(b)(ξ1)⊗ξ2⊗…⊗ξn,ϕ(b)(λξ1⊗…⊗λξn):=ϕ∗(b)(λξ1)⊗λξ2⊗…⊗λξn=λξ1⋅b∗⊗λξ2⊗…⊗λξn, and which factorizes through the Pimsner algebra . Indeed, for all it holds that , that is the operator on is right-multiplication by the element . A Pimsner algebra is universal in the following sense [18, Thm. 3.12]: ###### Theorem 2.3. Let be a -algebra and let be a -homomorphism. Suppose that there exist elements for all such that 1. for all and , 2. and for all and , 3. for all , 4. for all . Then there is a unique -homomorphism with for all . Also, in the context of this theorem the identity follows automatically. ###### Remark 2.4. In the paper [18], the pair was referred to as a Hilbert bimodule, since the map (taken to be injective there) naturally endows the right Hilbert module with a left module structure. As mentioned, our Assumption 2.1 simplifies the construction to a great extent (see also [3]). For the pair with a general -homomorphism , (in particular, a non necessarily injective one), the name -correspondence over has recently emerged as a more common one, reserving the terminology Hilbert bimodule to the more restrictive case where one has both a left and a right inner product satisfying an extra compatibility relation. ### 2.2. Six term exact sequences With a Pimsner algebra there come two six term exact sequences in -theory. Firstly, since factorizes through the compacts , the following class is well defined. ###### Definition 2.5. The class in defined by the even Kasparov module (with trivial grading) will be denoted by . Next, let denote the orthogonal projection with Im(P)=(⊕∞n=1E(n))⊕B⊆E∞. Notice that for all and thus for all . Then, let and recall that is the inclusion. ###### Definition 2.6. The class in defined by the odd Kasparov module will be denoted by . For any separable -algebra we then have the group homomorphisms [E]:KK∗(B,C)→KK∗(B,C),[E]:KK∗(C,B)→KK∗(C,B) and [∂]:KK∗(C,OE)→KK∗+1(C,B),[∂]:KK∗(B,C)→KK∗+1(OE,C), which are induced by the Kasparov product. The six term exact sequences in -theory given in the following theorem were constructed by Pimsner, see [18, Thm. 4.8]. ###### Theorem 2.7. Let be the Pimsner algebra of the pair over the -algebra . If is any separable -algebra, there are two exact sequences: KK0(C,B)1−[E]−−−−→KK0(C,B)i∗−−−−→KK0(C,OE)[∂]↑⏐⏐⏐⏐↓[∂]KK1(C,OE)←−−−−i∗KK1(C,B)←−−−−1−[E]KK1(C,B) and KK0(B,C)←−−−−1−[E]KK0(B,C)←−−−−i∗KK0(OE,C)⏐⏐↓[∂][∂]↑⏐⏐KK1(OE,C)i∗−−−−→KK1(B,C)1−[E]−−−−→KK1(B,C) with , the homomorphisms in -theory induced by the inclusion . ###### Remark 2.8. For , the first sequence above reduces to K0(B)1−[E]−−−−→K0(B)i∗−−−−→K0(OE)[∂]↑⏐⏐⏐⏐↓[∂].K1(OE)←−−−−i∗K1(B)←−−−−1−[E]K1(B) This could be considered as a generalization of the classical Gysin sequence in -theory (see [14, IV.1.13]) for the ‘line bundle’ over the ‘noncommutative space’ and with the map having the role of the Euler class of the line bundle . The second sequence would then be an analogue in -homology: K0(B)←−−−−1−[E]K0(B)←−−−−i∗K0(OE)⏐⏐↓[∂][∂]↑⏐⏐.K1(OE)i∗−−−−→K1(B)1−[E]−−−−→K1(B) Examples of Gysin sequences in -theory were given in [2] for line bundles over quantum projective spaces and leading to a class of quantum lens spaces. These examples will be generalized later on in the paper to a class of quantum lens spaces as circle bundles over quantum weighted projective spaces with arbitrary weights. ## 3. Pimsner algebras and circle actions An interesting source of Pimsner algebras consists of -algebras which are equipped with a circle action and subject to an extra completeness condition on the associated spectral subspaces. We now investigate this relationship. Throughout this section will be a -algebra and will be a strongly continuous action of the circle on . ### 3.1. Algebras from actions For each , define the spectral subspace A(n):={ξ∈A∣σz(ξ)=z−nξ forallz∈S1}. Then the invariant subspace is a -subalgebra and each is a (right) Hilbert -module over with right action induced by the algebra structure on and -valued inner product just , for all . ###### Assumption 3.1. The data as above is taken to satisfy the conditions: 1. The -algebra is separable. 2. The Hilbert -modules and are full and countably generated over the -algebra . ###### Lemma 3.2. With the -homomorphism simply defined by , the pair satisfies the conditions of Assumption 2.1. ###### Proof. To prove that is injective, let and suppose that for all . It then follows that for all . But this implies that for all . Since is full this shows that . We may thus conclude that is injective, and the image of is therefore closed. To conclude that it is now enough to show that the operator for all . But this is clear since . To prove that it suffices to check that for all (again since is full). But this is true being . ∎ The condition that both and are full over has the important consequence that the action is semi-saturated in the sense of the following: ###### Definition 3.3. A circle action on a -algebra is called semi-saturated if is generated, as a -algebra, by the fixed point algebra together with the first spectral subspace . ###### Proposition 3.4. Suppose that and are full over . Then the circle action is semi-saturated. ###### Proof. With refering to the norm-closure, we show that the Banach algebra cl(∞∑n=0A(n))⊆A is generated by and . A similar proof in turn shows that cl(∞∑n=0A(−n))⊆A is generated by and . Since the span is norm-dense in (see [10, Prop. 2.5]), this proves the proposition. We show by induction on that (A(1))n:=span{x1⋅…⋅xn∣x1,…,xn∈A(1)} is dense in . For the statement is void. Suppose thus that the statement holds for some . Then, let and choose a countable approximate identity for the separable -algebra . Let be given. We need to construct an element such that ∥x−y∥<ε . To this end we first remark that the sequence converges to . Indeed, this follows due to and since, for all , ∥x⋅um−x∥2=∥umx∗xum+x∗x−x∗xum−umx∗x∥. We may thus choose an such that ∥x⋅um−x∥<ε/3 . Since is full over , there are elements and so that ∥x⋅um−k∑j=1x⋅ξ∗j⋅ηj∥<ε/3 . Furthermore, since we may apply the induction hypothesis to find elements such that ∥k∑j=1x⋅ξ∗j⋅ηj−k∑j=1zj⋅ηj∥<ε/3 . Finally, it is straightforward to verify that for the element y:=k∑j=1zj⋅ηj∈(A(1))n+1 it holds that: . This proves the present proposition. ∎ Having a semi-saturated action one is lead to the following theorem [3, Thm. 3.1]. ###### Theorem 3.5. The Pimsner algebra is isomorphic to . The isomorphism is given by for all . In much of what follows, the -algebras of interest with a circle action, will come from closures of dense -graded -algebras, with the -grading defining the circle action in a natural fashion. Let be a -graded unital -algebra. The grading is compatible with the involution , this meaning that whenever for some . For , define the -automorphism by σw:x↦w−nxforx∈A(n)n∈Z. We will suppose that we have a -norm on satisfying ∥σw(x)∥≤∥x∥forallw∈S1x∈A, thus the action has to be isometric. The completion of is denoted by . The following standard result is here for the sake of completeness and its use below. The proof relies on the existence of a conditional expectation naturally associated to the action. ###### Lemma 3.6. The collection extends by continuity to a strongly continuous action of on . Each spectral subspace agrees with the closure of . ###### Proof. Once is shown to be dense in the rest follows from standard arguments. Thus, for , define the bounded operator by E(n):x↦∫S1wnσw(x) dw, where the integration is carried out with respect to the Haar-measure on . We have that for all and then that . This implies that is dense. ∎ Let now and consider the unital -subalgebra . Then is a -graded unital -algebra as well and we denote the associated circle action by . Let and choose a such that . Then σ1/dw(xnd)=wn⋅xnd=znd⋅xnd=σz(xnd),forallxnd∈A(nd), and it follows that for all . With the -norm obtained by restriction , it follows in particular that ∥σ1/dw(x)∥≤∥x∥ by our standing assumption on the compatibility of with the norm on . The -completion of is denoted by . ###### Proposition 3.7. Suppose that is semi-saturated on and let . Then we have unitary isomorphisms of Hilbert -modules (A(1))ˆ⊗ϕd≃(A1/d)(1)and(A(−1))ˆ⊗ϕd≃(A1/d)(−1) induced by the product . ###### Proof. We only consider the case of since the the proof for is the same. Observe firstly that . Thus Lemma 3.6 yields . This implies that the product is a well-defined homomorphism of right modules over (here “” refers to the algebraic tensor product of bimodules over ). Furthermore, since ⟨x1⊗…⊗xd,y1⊗…⊗yd⟩=x∗d⋅…⋅x∗1⋅y1⋅…⋅yd, we get that extends to a homomorphism of Hilbert -modules over with for all . It is therefore enough to show that is dense. But this is a consequence of [10, Prop. 4.8]. ∎ ###### Lemma 3.8. Suppose that satisfies the conditions of Assumption 3.1. Then satisfies the conditions of Assumption 3.1 for all . ###### Proof. We only need to show that the Hilbert -modules and are full and countably generated over . By Proposition 3.4 we have that is semi-saturated. It thus follows from Proposition 3.7 that A(d)≃(A(1))ˆ⊗ϕdandA(−d)≃(A(−1))ˆ⊗ϕd . (3.1) Since both and are full and countably generated by assumption these unitary isomorphisms prove the lemma. ∎ The following result is a stronger version of Theorem 3.5 since it incorporates all the spectral subspaces and not just the first one. ###### Theorem 3.9. Suppose that the circle action on satisfies the conditions in Assumption 3.1. Then the Pimsner algebra is isomorphic to the -algebra for all . The isomorphism is given by for all . ###### Proof. This follows by combining Lemma 3.8, Proposition 3.7 and Theorem 3.5. ∎ We finally investigate what happens when the -norm on is changed. Thus, let be an alternative -norm on satisfying ∥σw(x)∥′≤∥x∥′forallw∈S1andx∈A. The corresponding completion will carry an induced circle action . The next theorem can be seen as a manifestation of the gauge-invariant uniqueness theorem, [15, Thm. 6.2 and Thm. 6.4]. This property was indirectly used already in [18, Thm. 3.12] for the proof of the universal properties of Pimsner algebras. ###### Theorem 3.10. Suppose that for all . Then satisfies the conditions of Assumption 3.1 if and only if satisfies the conditions of Assumption 3.1. And in this case, the identity map induces an isomorphism of -algebras. In particular, we have that for all . ###### Proof. Remark first that the identity map induces an isometric isomorphism of Hilbert -modules for all . This is a consequence of the identity for all . But then we also have isomorphisms (A(1))ˆ⊗ϕn≃(A′(1))ˆ⊗ϕnand(A(−1))ˆ⊗ϕn≃(A′(−1))ˆ⊗ϕn for all . These observations imply that satisfies the conditions of Assumption 3.1 if and only if satisfies the conditions of Assumption 3.1. But it then follows from Theorem 3.5 that A≃OA(1)≃OA′(1)≃A′, with corresponding isomorphism induced by the identity map . ∎ ## 4. Quantum principal bundles and Z-graded algebras We start by recalling the definition of a quantum principal -bundle. Later on in the paper we shall exhibit a novel class of quantum lens spaces as principal -bundles over quantum weighted projective lines with arbitrary weights. ### 4.1. Quantum principal bundles Define the unital complex algebra O(U(1)):=C[z,z−1]/⟨1−zz−1⟩ where denotes the ideal generated by in the polynomial algebra in two variables. The algebra is a Hopf algebra by defining, for all , coproduct , antipode and counit . We simply write for short. Let be a complex unital algebra and suppose in addition that it is a right comodule algebra over , that is we have a homomorphism of unital algebras ΔR:A→A⊗O(U(1)), which also provides a coaction of the Hopf algebra on . Let denote the unital subalgebra of consisting of coinvariant elements for the coaction. ###### Definition 4.1. One says that the datum is a quantum principal -bundle when the canonical map can:A⊗BA→A⊗O(U(1)),x⊗y↦x⋅ΔR(y), is an isomorphism.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9850068092346191, "perplexity": 727.795181225801}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662594414.79/warc/CC-MAIN-20220525213545-20220526003545-00580.warc.gz"}
http://www.zndxzk.com.cn/paper/paperView.aspx?id=paper_319915	## Journal of Central South University 第50卷第7期总第299期 2019年7月 [PDF全文下载] [Flash在线阅读] (中南大学冶金与环境学院，湖南长沙，410083) Electrochemical synthesis of nickel isooctanoate School of Metallurgy and Environment, Central South University, Changsha 410083, China Abstract:The electrochemical synthesis of nickel isooctanoate was studied systematically. The effects of supporting electrolyte NaOH concentration, NaCl concentration, current density and temperature on the electrochemical synthesis process were investigated, and the optimal condition for each influencing factor was determined. The impurities were removed by dissolving and filtering, and finally the organic solvent was separated by distillation to obtain a final product. The product was qualitatively analyzed using FT-IR to determine the structure of the product, and the product was analyzed by dilute hydrochloric acid lysate. Finally, the electrolyte was repeatedly recycled. The results show that the optimal experimental condition is as follows: NaOH concentration of 0.2 mol/L, NaCl concentration of 2.0 mol/L, current density of 2 380 A/m2, temperature of 60 ℃. The yield is above 95%, the nickel content of the product is above 10%, and the technical indicators meet the requirements of Q/FMH02—2011. The product is identified as nickel isooctanoate by FT-IR. Through the circulation use experiment of the electrolyte, the nickel mass fraction, the yield and the impurities sodium mass fraction of the product in the five-cycle experiments are relatively stable, and the electrolyte can be recycled. Key words: electrochemical synthesis; nickel isooctanoate; recycling; FT-IR 中南大学学报（自然科学版） ISSN 1672-7207 CN 43-1426/NZDXZAC 中南大学学报（英文版） ISSN 2095-2899 CN 43-1516/TBJCSTFT	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8262580633163452, "perplexity": 4385.338238953138}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-05/segments/1642320304947.93/warc/CC-MAIN-20220126101419-20220126131419-00556.warc.gz"}
https://www.physicsforums.com/threads/matrix-of-a-linear-mapping.623390/	# Matrix of a linear mapping 1. Jul 25, 2012 ### juanma101285 Hi, I have the following problem that is solved, but I get lost at one step and cannot find how to do it in the notes. I would really appreciate it if someone could tell me where my teacher gets the result from. The problem says: "Find the matrix of linear mapping $T:P_3 → P_3$ defined by $(Tp)(t)=p(t)+p'(t)+p(0)$ with respect to the basis {$1,t,t^2,t^3$} of $P_3$. Deduce that, given $q \in P_3$, there exists $p \in P_3$ such that $q(t)=p(t)+p'(t)+p(0)$." And I get lost here... It says: "We have $T(1)=2$ $T(t)=1+t$ $T(t^2)=2t+t^2$ $T(t^3)=3t^2+t^3$" So I don't know why it says $T(1)=2$.... I think $T(t)=1+t$ because it is the derivative of t plus t, and $T(t^2)$ is the derivative of $t^2$ plus $t^2$... But why T(1)=2? Thanks a lot! 2. Jul 25, 2012 ### Muphrid I think this would be clearer written slightly differently. $$T[p(t)] = p(0) + \frac{dp}{dt} + p(t)$$ When you say $T(1)$, you substitute $p(t) = 1$ into the above. Clearly, then, $p(0) = 1$ because $p(t) = 1$ for any $t$. That takes care of the first and last terms. The derivative is zero because $p$ is a constant. In short, you get $$T(1) = 1 + 0 + 1 = 2$$ 3. Jul 25, 2012 ### Fredrik Staff Emeritus T takes polynomials to polynomials, so when he writes T(1), 1 denotes a polynomial. The only polynomial that it makes sense to denote by 1 is the function that takes every real number to 1. It might be less confusing to denote it by a symbol like I instead. Then for all real numbers t, we have $(T(I))(t)=I(t)+I'(t)+I(0)=1+0+1$, as Muphrid has already said. So T(I) is the polynomial that takes every real number t to 2. In this context, it seems to be standard to denote this polynomial by 2. I think this notation is worse, because now it looks like T is acting on the real number p(t) instead of on the polynomial p. Last edited: Jul 25, 2012 4. Jul 25, 2012 ### Fredrik Staff Emeritus I don't understand this argument. To find T(t), you need to do something similar to what I did above. Here t denotes the identity map on the set of real numbers, i.e. the function that takes every real number to itself. If we use this notation, then for all real numbers s, we have $(T(t))(s)=t(s)+t'(s)+t(0)=s+1+0$. So T(t) is the polynomial that takes s to 1+s. In this notation, that polynomial is denoted by 1+t. This problem shows how confusing it can be to use notations like t2 both for a number (the square of the number t) and a function (the function that takes every real number to its square). I would prefer to use a different notation for the basis vectors, for example $\{e_1,e_2,e_3,e_4\}$ instead of $\{1,t,t^2,t^3\}$, where the $e_i$ are defined by $e_1(s)=1$ for all s. $e_2(s)=s$ for all s. ...and so on. Now what the problem writes as T(1) and T(t) can be written as $Te_0$ and $Te_1$ respectively, and for all $t\in\mathbb R$, $Te_1(t)=e_1(t)+e_1'(0)+e_1(0)=1+0+1=2=2(e_1(t))=(2e_1)(t),$ $Te_2(t)=e_2(t)+e_2'(0)+e_2(0)=t+1+0=e_2(t)+e_1(t)=e_1(t)+e_2(t)=(e_1+e_2)(t)$. Since this holds for all t, we have $Te_1=2e_1$ and $Te_2=e_1+e_2$. Can you do $T(t^2)$ and $T(t^3)$ now? You can stick to the t^something notation if it doesn't confuse you, but then you will have to write weird things like ${t^2}'(s)=2s$. Last edited: Jul 25, 2012 5. Jul 26, 2012 ### HallsofIvy Staff Emeritus The derivative of the polynomial p(t)= 1 (for all t) is 0 so p(t)+ p'(t)+ p(0)= 1+ 0+ 1= 2. More precisely p(t)+ p'(t)+ p(0)= t+ 1+ 0= t+ 1 Again, $p(t)+ p'(t)+ p(0)= t^2+ 2t+ 0= t^2+ 2t$ Similar Discussions: Matrix of a linear mapping	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 2, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9704952836036682, "perplexity": 427.5860991140174}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-51/segments/1512948551162.54/warc/CC-MAIN-20171214222204-20171215002204-00090.warc.gz"}
https://mathoverflow.net/questions/153730/example-of-elliptic-curve-with-cm-complex-multiplication-by-sqrt-7/153734	# Example of elliptic curve with CM (complex multiplication) by \sqrt{-7} Can someone give me an example of elliptic curve with CM by sqrt(-7) with the action. I've found a list of examples in the following link but not the action. http://planetmath.org/examplesofellipticcurveswithcomplexmultiplication I am sure others (magma, etc) can do the same. With sage the following lines will produce the rational functions $\bigl(f(x,y), g(x,y)\bigr)$ representing the multiplication by $(1\pm\sqrt{-7})/2$ on $E$ in the Weierstrass equation given at the link. Once you have that you can get all endomorphisms. sage: E = EllipticCurve([1,-1,0,-2,-1]) sage: K.<t> = NumberField(x^2+7) sage: EK = E.base_extend(K) sage: psis = EK.isogenies_prime_degree(2) sage: [psi.codomain().is_isomorphic(EK) for psi in psis] [True, True, False] sage: psi = psis[0] sage: iota = psi.codomain().isomorphism_to(EK) sage: psi.set_post_isomorphism(iota) sage: psi.rational_maps() whose $x$-coordinate $f(x,y)$ is $$\frac{(\sqrt{-7} - 3)\cdot x^2 + (-2\, \sqrt{-7} - 2)}{8\,x + \sqrt{-7} + 5}$$ • The formula for the CM by $(1+\sqrt{-7})/2$ is much simpler than the formula for CM by $\sqrt{-7}$, and the former is actually more useful, since it generates the full endomorphism ring, while $\mathbb{Z}[\sqrt{-7}]$ is only a subring. (So you statement that from $[\sqrt{-7}]$ you can get all endomorphisms is not accurate.) – Joe Silverman Jan 6 '14 at 13:33 • Absolutely right. I added the simpler, but I will now delete the earlier. – Chris Wuthrich Jan 6 '14 at 13:38 • Maybe the sage session will render better and highlight if you add four spaces in the beginning of code. – joro Jan 6 '14 at 14:59 • Just a note (mostly for myself): the desired endomorphism must have degree 2 by Corollary II.1.5(b) in Silverman's "AAEC" book. (That's also why $\left[ \sqrt{-7} \right]$ has degree 7 and hence is more complicated...). – Watson May 7 at 19:22 See J. Silverman, Advanced Topics in the Arithmetic of Elliptic Curves (Springer GTM), Proposition 2.3.1. Note that since the class number of $\mathbb{Q}(\sqrt{-7})$ is 1, this is the only example defined over $\mathbb{Q}$. • Ha!! I was in the middle of typing the same reference when your answer appeared. So you win! Hint for OP: The curve has an endomorphism of degree 2 corresponding to $(1+\sqrt{-7})/2$. There's a general formula for degree 2 isogenies $E\to E'$, so one need merely use that formula and make the additional assumption that $j(E)=j(E')$ to find the desired equation. – Joe Silverman Jan 6 '14 at 13:26 • Sorry to steal the answer from you! – abx Jan 6 '14 at 13:28 • thanks for the help. going through the above mentioned book now. do I need to know any kind of programming language to get the exact action (not particularly for \sqrt(-7) but for any CM)? – user45145 Jan 9 '14 at 7:23	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7908755540847778, "perplexity": 796.6645408086408}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-31/segments/1627046153474.19/warc/CC-MAIN-20210727170836-20210727200836-00414.warc.gz"}
https://community.canvaslms.com/t5/Studio-Users/Can-I-move-where-where-closed-captions-appear-in-Arc/m-p/157838/highlight/true	cancel Showing results for Did you mean: Surveyor Can I move where where closed captions appear in Arc? When using the closed captions function in Arc, the captions appear at the top of the screen. Is there a way to have the closed captions to appear at the bottom of the screen? Tags (2) 1 Solution Accepted Solutions Navigator Not currently. When we met in July with the Arc team at InstructureCon, they indicated that it was put at the top so that it didn't appear over the user comments that are shown at the bottom of the screen. This was in response to the concern I voiced that the font is too small and the WebVTT standard allows for positioning information, yet they are ignoring it. 3 Replies Navigator Hi Taylor, I'm going to share this question over with the Arc Users Group‌. I'm sure someone in that group can help answer your question. Navigator Not currently. When we met in July with the Arc team at InstructureCon, they indicated that it was put at the top so that it didn't appear over the user comments that are shown at the bottom of the screen. This was in response to the concern I voiced that the font is too small and the WebVTT standard allows for positioning information, yet they are ignoring it. Surveyor Thanks, James. I agree. The font is too small.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9630440473556519, "perplexity": 1382.9215767267567}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178360853.31/warc/CC-MAIN-20210228115201-20210228145201-00611.warc.gz"}
http://www.dcode.fr/modular-exponentiation-calculus	Search for a tool Modular Exponentiation Tool to compute modular power. Modular Exponentiation (or power modulo) is the result of the calculus a^b mod n. It is often used in informatics and cryptography. Results Modular Exponentiation - Tag(s) : Mathematics, Arithmetics dCode and you dCode is free and its tools are a valuable help in games, puzzles and problems to solve every day! You have a problem, an idea for a project, a specific need and dCode can not (yet) help you? You need custom development? Contact-me! Team dCode read all messages and answer them if you leave an email (not published). It is thanks to you that dCode has the best Modular Exponentiation tool. Thank you. # Modular Exponentiation ## Modular Exponentiation Calculus a^b mod n Tool to compute modular power. Modular Exponentiation (or power modulo) is the result of the calculus a^b mod n. It is often used in informatics and cryptography. ### How to calculate a raised to power b modulo n? It consists in an exponentiation followed by a modulus, but it exists optimized algorithms with big numbers to return a fast result without having to actually perform the calculation (called fast, thanks to mathematical simplifications). Example: $$12^{34} \equiv 16 \mod 56$$ Power indicates the name of the operation, and Exponent to indicate the operand. ### What it the algorithm of powmod? There are several algorithms, here is the simplest in pseudocode:function powmod(base b, exponent e, modulus m) if m = 1 then return 0 var c := 1 for var a from 1 to e c := (c * b) mod m end for return c ### How to solve for exponent with base and modulo? This calculation is known as the discrete logarithm problem. Some solutions can be found by brute force but there is no simple general solution. ### Why modular exponentiation is limited to integers? Calculus uses exponent and modulos that are generally defined over the natural number domain set N. It is possible to use rational numbers but it is not handled here.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7467033267021179, "perplexity": 1369.8145375637407}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-43/segments/1508187826840.85/warc/CC-MAIN-20171023221059-20171024001059-00111.warc.gz"}
https://www.tubesandmore.com/products/circuit-design?filters=2341a2395c2334a2335c2327a2334c2326a2327	# Circuit Design #### Kester Kester is a global supplier of assembly materials for electronic assembly, including various types of solder. Solder - Kester, 60 / 40, 44 Flux, 1 lb spool 60/40 Rosin Core, 1 lb Spool, contains lead alloy. Kester 44 Rosin Flux is an activated rosin formula for use in flux-cored solder wire. Kester 44 Rosin Flux has virtually dominated the field of activated rosin core solders for well over four decades. An outstanding performance feature of this flux is the “instant-action” wetting behavior. $34.45 Solder - Kester, 60 / 40, 44 Flux, 66 Core, .031 Dia, .5 oz Kester 44 60/40 rosin core type. .031" diameter, 0.5 oz$5.78 Solder - Kester 63 / 37, 1 lb spool, 0.031" diameter (63/37 Rosin Core) - ..031" Diameter, 1 lb Spool, contains lead alloy. Kester 44 Rosin Flux is an activated rosin formula for use in flux-cored solder wire. Kester 44 Rosin Flux has virtually dominated the field of activated rosin core solders for well over four decades. An outstanding performance feature of this flux is the “instant-action” wetting behavior. $31.95 Solder - Kester 48, .031", Flux 66, Lead-free 1 lb Spool Lead free solder, Sn96.5Ag3.0Cu0.5, 031" diameter, rosin flux, core 66. Kester SAC305 48 Activated Rosin Flux for cored solder wire was developed for lead-free applications to enable soldering of most common metals. Starting at$80.00	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.20495542883872986, "perplexity": 28475.31829170486}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-17/segments/1618038075074.29/warc/CC-MAIN-20210413213655-20210414003655-00492.warc.gz"}
https://mathoverflow.net/questions/244300/arakelov-divisors-and-the-meaning-of-real-coefficients	Arakelov divisors and the meaning of real coefficients I'm learning Arakelov theory on arithmetic surfaces and I have the following general question. Let $K$ be a number field and consider its ring of integers $O_K$. Moreover let $S:=\operatorname{Spec} O_K$ and consider a regular, projective arithmetic surface $\pi: X\to S$. For every embedding $\sigma:K\to\mathbb C$ we have the fiber at infinity $X_\sigma$ which is a Riemann surface. If we fix a Kalher metric $\Omega_\sigma$ on each $X_\sigma$, then an Arakelov divisor can be written uniquely as: $$\hat D:=D+\sum_{\sigma}\alpha_\sigma X_\sigma$$ where $D$ is a usual divisor of $X$ and $\alpha_\sigma\in\mathbb R$. I don't understand why the coefficients for the fibers at infinity are in $\mathbb R$ and not in $\mathbb Z$, why do we need this? Foe example consider the real vector $\varepsilon=(\varepsilon_\sigma)_\sigma$ where for every $\sigma$ the real number $\varepsilon_\sigma$ is small enough and construct the Arakelov divisor $$\hat D_\varepsilon:=D+\sum_{\sigma}(\alpha_\sigma+\varepsilon_\sigma) X_\sigma$$ (note that $D$ is fixed) What are the geometrical differences between $\hat D$ and $\hat D_\varepsilon$? • You can define formal linear combinations with integer coefficients if you want, but already at very early steps in the theory you will find difficulties. For instance, check the definition of principal Arakelov divisors. The coefficients at infinity are not integers (in general). Jul 14 '16 at 19:25 • Arakelov's arithmetic intersection pairing on arithmetic surfaces has been extended by Deligne and Gillet-Soulé. In these more general approaches, an arithmetic divisor is a pair $(D,g_D)$, where $g_D$ is a Green current at infinity. The choice of a Kähler form allows to normalize the Green current up to scalars (at each place). — Although this does not answer the question, it may help explain the appearance of real coefficients. – ACL Jul 15 '16 at 0:23 • You should take a look at Durov's work. Your intuition that $\mathbb{R}$ is "too many" coefficients is correct. I think Durov just uses $Log(\mathbb{Q}^+)$. Apr 13 '17 at 12:56 Changing the coefficient of a divisor by some $\epsilon > 0$ can have a very significant effect, for example it can move you out of the nef cone. Indeed, even in non-Arakelov algebraic geometry it is often very useful to allow real coefficients on divisors. As a specific example, let $A$ be a simple abelian variety with CM by a real quadratic field. Then $\text{NS}(A)\otimes\mathbb Q$ has rank 2, say generated by $D_1$ and $D_2$, but the boundary of the nef cone in $\text{NS}(A)\otimes\mathbb R$ is spanned by divisors of the form $aD_1+bD_2$ with $a/b\notin\mathbb Q$. Another reason one might use real coefficients is that the image of $\text{NS}(X)$ in $\text{NS}(X)\otimes\mathbb R$ is a lattice in a finite dimensional vector space, so now one can use geometry to study $\text{NS}(X)$.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9689351320266724, "perplexity": 160.8663308186098}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-49/segments/1637964363337.27/warc/CC-MAIN-20211207075308-20211207105308-00371.warc.gz"}
http://mathhelpforum.com/calculus/33243-couple-more-optimization-problems-print.html	# A couple more optimization problems • April 4th 2008, 07:04 PM NAPA55 A couple more optimization problems Couldn't figure this one out for the life of me... got a few steps down and then it all went downhill from there. If the concentration of a drug in the bloodstream at time "t" is given by this function, http://img395.imageshack.us/img395/9...tionfd7.th.jpg where a, b(b>a), and k are positive constants that depend on the drug, at what time is the concentration at its highest level? And the second question: The motion of a particle is given by s(t) = 5cos(2t + pi/4). What are the maximum values of the displacement, the velocity, and the acceleration? • April 4th 2008, 07:06 PM Mathstud28 I'd help but I cant read the paper...rewrite it...preferably in LaTeX • April 4th 2008, 07:27 PM TheEmptySet Quote: Originally Posted by NAPA55 Couldn't figure this one out for the life of me... got a few steps down and then it all went downhill from there. If the concentration of a drug in the bloodstream at time "t" is given by this function, http://img395.imageshack.us/img395/9...tionfd7.th.jpg where a, b(b>a), and k are positive constants that depend on the drug, at what time is the concentration at its highest level? And the second question: The motion of a particle is given by s(t) = 5cos(2t + pi/4). What are the maximum values of the displacement, the velocity, and the acceleration? $c(t)=\frac{k}{b-a}\left[ e^{-at}-e^{-bt}\right]$ Taking the derivative we get... $\frac{dc}{dt}=\frac{k}{b-a}\left[ -ae^{-at}+be^{-bt}\right]$ setting equal to zero and solving we get $-ae^{-at}+ be^{-bt}=0 \iff \frac{a}{b}=\frac{e^{-bt}}{e^{-at}}\iff \frac{a}{b}=e^{(a-b)t} \iff ln \left( \frac{a}{b}\right)=(a-b)t$ $t= \frac{ln \left( \frac{a}{b}\right)}{a-b}$	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 4, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8256736397743225, "perplexity": 790.6382950920489}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-35/segments/1408500829661.96/warc/CC-MAIN-20140820021349-00226-ip-10-180-136-8.ec2.internal.warc.gz"}
http://math.stackexchange.com/questions/19424/describing-a-particular-quotient-ring-involving-a-subring-of-mathbbqx	# Describing a particular quotient ring involving a subring of $\mathbb{Q}[x]$ I had to do some homework problems involving the polynomial ring $R=\mathbb{Z}+x\,\mathbb{Q}[x]\subset\mathbb{Q}[x]$. This is an integral domain but not a UFD. Further, $x$ is not prime in $R$. One of the problems was to describe to $R/(x)$. Since $x$ is not a prime element, we know $(x)$ is not a prime ideal. So at the very least, $R/(x)$ is not an integral domain.... but what else can I say? This is perhaps something I should not admit, but problems of this form have always befuddled me. I know there's not any one "answer" they're looking for, but I never quite know what to say. Anyway, this homework has been submitted already, so I am not including a homework tag. I'm just curious how you all would describe this particular quotient. - The key is to understand what that ideal $(x)$ looks like in the first place. So, clearly all polynomials in that ideal have degree at least 1, but what degree 1 polynomials can occur? For $f(x)*x$ to have degree 1, $f(x)$ must have a non-zero constant term. That term must be in $\mathbb{Z}$, and it is easy to see that you get any coefficients for higher degrees. So $(x)=\mathbb{Z}x + \mathbb{Q}x^2+\ldots+\mathbb{Q}x^n+\ldots$. Thus, in the quotient, any coset is represented by some $n + ax$, $n\in \mathbb{Z},a\in \mathbb{Q}$, and another element $m+bx$ represents a different coset if and only if $n\neq m$ or $a-b\notin\mathbb{Z}$. In other words, the quotient is isomorphic to $\left(\mathbb{Z} + \mathbb{Q}/\mathbb{Z}x\right)/(x^2).$	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8696664571762085, "perplexity": 128.66689096845897}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-40/segments/1443736673439.5/warc/CC-MAIN-20151001215753-00012-ip-10-137-6-227.ec2.internal.warc.gz"}
https://dials.github.io/dials-2.2/documentation/programs/dials_estimate_gain.html	This documentation page refers to a previous release of DIALS (2.2). # dials.estimate_gain¶ ## Introduction¶ This program can be used to estimate the gain of the detector. For pixel array detectors the gain is usually set to 1.00. This means that the pixels behave according to Poisson statistics. However, for older CCD detectors the gain may have a different value. This value is important because it can affect, amongst other things, the ability of the spot finding algorithm which can result in noise being identified as diffraction spots. Examples: dials.estimate_gain models.expt ## Basic parameters¶ kernel_size = 10,10 max_images = 1 output { gain_map = None } ## Full parameter definitions¶ kernel_size = 10,10 .type = ints(size=2, value_min=1) max_images = 1 .help = "For multi-file images (NeXus for example), report a gain for each" "image, up to max_images, and then report an average gain" .type = int(allow_none=True) output { gain_map = None .help = "Name of output gain map file" .type = str }	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6789920926094055, "perplexity": 4510.602247291906}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-45/segments/1603107874637.23/warc/CC-MAIN-20201021010156-20201021040156-00638.warc.gz"}
https://www.sas1946.com/main/index.php?topic=47154.24	• November 27, 2020, 01:29:20 AM • Welcome, Guest Pages: 1 2 [3] 4 5 6 ... 14 Go Down ### AuthorTopic: IL-2 Random Skies Mod v2.7 (Read 49434 times) 0 Members and 1 Guest are viewing this topic. #### SAS~Storebror • retired • SAS Honourable Member • member • Offline • Posts: 19890 • Taking a timeout ##### Re: Random Skies Mod v1.0 (23-July-2015) « Reply #24 on: July 24, 2015, 09:06:21 AM » Thanks whistler, makes perfectly sense. You know I'm a triple-checker type of guy, so I gave it a try and can confirm that your script is clean, the generated exe is clean and all tools involved apparently were clean as well. Best regards - Mike Logged What goes around comes around, you'll see #### whistler • Modder • member • Offline • Posts: 2283 ##### Re: Random Skies Mod v1.0 (23-July-2015) « Reply #25 on: July 24, 2015, 09:17:50 AM » And very lucky we are you did check it! I was starting to feel a bit uncomfortable... I have no plans to develope it further unless there are big changes in CUP or an important bug is reported. If it makes the community feel safer, a trusted member of this board can host this very version verified by you ... Cheers! Logged NG-HUD v3.5H \| NG-MAP v3.1 \| NG-CAM v1.6: https://www.sas1946.com/main/index.php/board,93.0.html #### Darkwind • member • Offline • Posts: 240 ##### Re: Random Skies Mod v1.0 (23-July-2015) « Reply #26 on: July 24, 2015, 11:50:23 PM » I didn't hesitate or have a second thought about downloading from the other sites you offered. I trust SAS and you as well. Thanx so much for your time and effort, this is truly a neat little mod. Logged #### whistler • Modder • member • Offline • Posts: 2283 ##### Re: Random Skies Mod v1.0a (26-July-2015) « Reply #27 on: July 26, 2015, 02:59:10 AM » Thanks Darkwind! Silent update: I have reworked the Random.bat file a little to add one new feature and to allow a better control to texture editors. - The last texture name used is saved to the "Files/last.txt" for your convenience. I like this sky! which one is it? - At some point texture creators may want to use custom Noise files. If you now add a noise tga file to the "Noise" folder with the exact same name than texture, the batch file will use this file instead of the default "CloudsNoise003.tga". I thought it was a pitty to leave this already built-in feature behind... - Also now included "CloudsNoise005.tga" from tbauchot for texture creators to use it if they want. - TB New Skies Textures Pack updated to take advantage of this new feature (3 textures use a different noise file than the others). The executable remains the same. Just overwrite everything. Cheers Logged NG-HUD v3.5H \| NG-MAP v3.1 \| NG-CAM v1.6: https://www.sas1946.com/main/index.php/board,93.0.html #### Peter Lynn • member • Offline • Posts: 345 ##### Re: Random Skies Mod v1.0a (26-July-2015) « Reply #28 on: July 26, 2015, 03:14:49 AM » Thank you. Great mod! Logged #### WindWpn • Modder • member • Offline • Posts: 952 ##### Re: Random Skies Mod v1.0a (26-July-2015) « Reply #29 on: July 27, 2015, 10:00:06 AM » Great mod! Wondering, does it make sense to update all load.ini files to ensure: Code: [Select] HighClouds = Clouds256.tga HighCloudsNoise = CloudsNoise.tga I have a number of custom map installs, and though most employ the standard Clouds256.tga, some, I see, have custom named values. Of course these textures are located in the _Tex folder, but wondering if all those could be removed and simply use this mod pattern to load the appendix high cloud textures randomly? I also updated my config which uses TotalModder to call the random.bat alone prior to loading TM which works well in my highly customized HSFX based il2 install. ~S~ wind Logged #### whistler • Modder • member • Offline • Posts: 2283 ##### Re: Random Skies Mod v1.0a (26-July-2015) « Reply #30 on: July 27, 2015, 11:25:05 AM » Hi WindWpn The launcher is just a wrapper to humanize the scripts. All work is done in the Random.bat and depending on the argument you pass, it does one thing or another. So you can use either: "#SAS\Random Skies\Files\Random.bat" [empty] -> Random (all texture folders) "#SAS\Random Skies\Files\Random.bat" Light -> Random Light folder "#SAS\Random Skies\Files\Random.bat" Medium -> ... "#SAS\Random Skies\Files\Random.bat" Heavy "#SAS\Random Skies\Files\Random.bat" Custom The Stock option calls the Reset.bat and it removes all files, allowing you to use the internally stored textures. These batch files where writen as standalone (as long as they are place where they should), as you have noticed already. The best approach for you is to edit every custom-added map load.ini: Code: [Select] // HighClouds = ThisMapClouds.tga// HighCloudsNoise = ThisMapNoise.tga HighClouds = Clouds256.tga HighCloudsNoise = CloudsNoise.tga The custom textures remain where they are and you can always revert it back. Or just replace the first 2 lines with the other 2 and delete the custom textures. Up to you! Logged NG-HUD v3.5H \| NG-MAP v3.1 \| NG-CAM v1.6: https://www.sas1946.com/main/index.php/board,93.0.html #### SAS~Monty27 • SAS Team • member • Offline • Posts: 3825 • Focus on the solution, not the problem. ##### Re: Random Skies Mod v1.0a (26-July-2015) « Reply #31 on: August 01, 2015, 07:28:46 PM » Absolutely love this Whistler, and tbauchot too, big thanks. Thanks for building the full support for CUP as discussed. Mods like this make Il2 a more comprehensive flight simulator, what a toolset we have now! Logged #### spartan18a • Supporter • member • Offline • Posts: 686 ##### Re: Random Skies Mod v1.0a (26-July-2015) « Reply #32 on: August 02, 2015, 04:25:39 AM » So, will it be implemented in the next CUP update? I guess so, right? Logged Winning is optional, but trying your best is not. #### SAS~Monty27 • SAS Team • member • Offline • Posts: 3825 • Focus on the solution, not the problem. ##### Re: Random Skies Mod v1.0a (26-July-2015) « Reply #33 on: August 10, 2015, 07:12:56 PM » The JSGME-Def-Skies Options are there already and will also be included in the up-coming TGA release. Other than that what is there to do? The install of this utility is explained very well here. Its easy to do and it works. I will also highlight the thread in CUP, as should others with plenty of lovely screenshots... Logged #### spartan18a • Supporter • member • Offline • Posts: 686 ##### Re: Random Skies Mod v1.0a (26-July-2015) « Reply #34 on: August 11, 2015, 02:08:41 AM » Thanks Monty. Love CUP Logged Winning is optional, but trying your best is not. #### whistler • Modder • member • Offline • Posts: 2283 ##### Re: Random Skies Mod v1.0b (24-Jan-2016) « Reply #35 on: January 24, 2016, 05:46:12 AM » Careful! The luncher has a new executable name! delete old "Random Skies Launcher v1.0.exe" and use the new one. I Added a new context menu. Right click anywhere to access new options: Hope you like these additions! I find myself going to these locations too often and I thought this could come in handy. Now I have only one shortcut on the desktop. Cheers! Logged NG-HUD v3.5H \| NG-MAP v3.1 \| NG-CAM v1.6: https://www.sas1946.com/main/index.php/board,93.0.html Pages: 1 2 [3] 4 5 6 ... 14 Go Up Page created in 0.015 seconds with 26 queries.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4900462031364441, "perplexity": 18178.221005536114}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-50/segments/1606141191511.46/warc/CC-MAIN-20201127073750-20201127103750-00246.warc.gz"}
http://math.stackexchange.com/questions/76844/solution-to-an-ode-cant-follow-a-step-of-a-stability-example	# Solution to an ODE, can't follow a step of a Stability Example In my course notes, we are working on the stability of solutions, and in one example we start out with: Consider the IVP on $(-1,\infty)$: $x' = \frac{-x}{1 + t}$ with $x(t_{0}) = x_{0}$. Integrating, we get $x(t) = x(t_{0})\frac{1 + t_{0}}{1 + t}$. I can't produce this integration but the purpose of the example is to show that $x(t)$ is uniformly stable, and asymptotically stable, but not uniformly asymptotically stable. But I can't verify the initial part and don't want to just skip over it. Can someone help me with the details here? Update: the solution has been pointed out to me and is in the answer below by Bill Cook (Thanks!). - ## 1 Answer Separate variables and get $\int 1/x \,dx = \int -1/(1+t)\,dt$. Then $\ln\|x\|=-\ln\|1+t\|+C$ Exponentiate both sides and get $\|x\| = e^{-\ln\|1+t\|+C}$ and so $\|x\|=e^{\ln\|(1+t)^{-1}\|}e^C$ Relabel the constant drop absolute values and recover lost zero solution (due to division by $x$) and get $x=Ce^{\ln\|(1+t)^{-1}\|}=C(1+t)^{-1}$. Finally plug in the IC $x_0 = x(t_0)=C(1+t_0)^{-1}$ so that $C=x_0(1+t_0)$ and there you go the solution is $$x(t) = x_0 \frac{1+t_0}{1+t}$$ - Wow thank you so much. I can't believe I forgot how to solve a separable first order ODE. :S Thanks very much though! – Kyle Schlitt Oct 29 '11 at 2:07	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9030112624168396, "perplexity": 346.28432646053807}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-52/segments/1418802769709.84/warc/CC-MAIN-20141217075249-00021-ip-10-231-17-201.ec2.internal.warc.gz"}
https://euro-math-soc.eu/review/hyperspace	# Hyperspace In 2016 Oxford University Press started a Landmark Science series with cheap reprints of classic books, the 'must-reads', about topics that have shaped current science. Here I review two of the more mathematical/physical ones from the first release if seven books in April 2016: this book and The Emperor's New Mind (R. Penrose). Like Penrose, Kaku gives in this book also an overview of how physics and our understanding of the laws that govern nature and the cosmos. Where Penrose's main objective was to understand the human mind and brain and uses a lot of technical material, Kaku's story is much more accessible and sticks more to the quest of a unifying theory that captures all the laws of physics. As physicists of the 20th century constructed more complex theories that picked up more of the laws that describe phenomena, considered of different nature before, they needed to extend the dimension of the space in which they had to be described. This need for higher dimensions provides the thread that runs through the book and that also was the inspiration for the title. Kaku divides his book in four parts. In the first part he prepares the reader for the roller coaster he is about to enter. The four forces that need to be unified are Maxwell electromagnetic force, strong and weak nuclear force, and gravitational force. We are introduced to the queer higher dimensional world and a world that is not flat. We get a sneak preview of where this may lead us: black holes, wormholes, and time travel. He more or less assumes we are familiar with the classical theory of Newtonian mechanics and presents a first unification by introducing the Riemannian tensor for the Kaluza-Klein theory which consists of the 4-dimensional Einstein block, bordered by a row and column to include Maxwell's theory. In part two, we get the more recent history in search for the unification. It starts with the observations that have led to the development of quantum theory that, when followed consequently, has strange and unexplainable consequences. The Yang-Mills field theory replaced the classical Maxwell theory. Here we also meet with Einstein's reluctance towards quantum theory's 'spooky action at a distance'. Till then the theory was carved in marble he said, quantum theory was made from wood, and he wanted to build a theory that was just marble, no wood. This metaphore of opposing viewpoints is taken along by Kaku as his book develops. Einstein's relativity theory where gravity is explained by space-time curvature is of a different nature that does not mix well with quantum field theory. That is why the Standard Model could explain and unify the electromagnetic and the strong and weak nuclear forces but leaves out gravitation which is too weak a force to fit. Gradually more wood is turned into marble, i.e. using geometric arguments, by bordering the Riemann tensor with the Yang-Mills field. The many subatomic quarks and leptons were rather messy and symmetry was lost but that problem was solved by supergravity (and supersymmetry), lifting the tensor to an even higher N-dimensional space, so that more symmetry could be assumed. Enter string theory, exit supergravity in the effort to include gravity. This is where Kaku himself has contributed. Here the general N is naturally' forced to be 10 for mathematical reasons. According to Kaku, this is something that could be explained by studying modular functions in Ramanujan's lost notebook. Recall that Kaku wrote his book in 1994, and the theory was still young. Since experimental verification is not possible with the energy we have available here on Earth, we have to look outside to cosmic phenomena and the origin of the universe. Kaku even takes the time to go through several historical proofs for the existence of God as a creator of it all. The two remaining parts will certainly be appreciated by lovers of Science Fiction. Kaku explores in part 3 what the theory so far would make possible in principle. So we learn the possibilities created by black holes, wormholes and time travel. The possible interpretation of quantum theory dealing with many universes. The last part speculates on the what if' aspect of the future. What if our civilization ever reaches a type II level where it becomes possible to control the amounts of energy of our sun, or even type III where it becomes possible to work with the energy of an entire galaxy. Do such civilizations exist and if so, why didn't they contact us? Perhaps they never reach it because of disastrous events happened as they did on our planet according to geological observations. And what will eventually happen with the whole universe? Although the book is about physics, the battlefield is on the mathematical structure that is used. Topology is what should bind the Riemannian geometry of Einstein and the Lie groups of quantum physics. Mathematics and physics were in close harmony for many centuries. They started to develop in different directions late 19th and early 20th century. It turned out that at the dawn of the 21st century they need each other more than ever, which raises the philosophical question of all times: why this `unreasonable effectiveness of mathematics in the natural sciences' as E. Wigner formulated it. If you are looking for the mathematics, that you will not find in this book, but it will convince you, if that is still needed, that mathematics is the key to understand nature. Of course, theoretical physics and mathematics did not stop evolving after this book was written, gravitational waves were observed in 2016, the Higgs boson was identified in 2012, the tau neutrino in 2000, etc. Neither did Kaku stop form 'spreading the news'. He is present in the media and wrote several other popular books since, just a couple of examples: Parallel Worlds: A Journey through Creation, Higher Dimensions, and the Future of the Cosmos (2004), Physics of the Impossible: A Scientific Exploration into the World of Phasers, Force Fields, Teleportation, and Time Travel (2008), and a recent one that relates to the book of Penrose mentioned in the beginning: The Future of the Mind: The Scientific Quest to Understand, Enhance, and Empower the Mind (2014). However, the current Hyperspace book was his biggest success so far. So one should be aware that as Kaku brings the reader of this book to the level of superstrings, this is in the context of the euphoria of the early 1990s. Nevertheless, it is still mostly entertaining to read this book about the evolution of theoretical physics up to that point. It is the best documentation for the layman of this history that I know of. He does avoid the technical stuff that most of those readers will probably skip anyway, and yet it gives so much details that takes you along on A Scientific Odyssey Trough Parallel Universes, Time Warps, and The Tenth Dimension which is rightfully the subtitle of the book. Reviewer: Book details This is a reprint of the original book of 1994. Kaku introduces the reader to theoretical physics from Einstein's relativity theory and quantum physics to string theory. He takes the reader along on an entertaining story, avoiding in gracious slaloms all the technical material. In the later part he amazes with possibilities of wormholes and time machines and civilizations that are far beyond our lifespan but that have inspired many an SF author. ## Publisher: Published: 2016 ISBN: 9780198785033 (pbk) Price: £9.99 (pbk) Pages: 384 Categorisation	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6483743786811829, "perplexity": 671.854256628439}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-40/segments/1664030337432.78/warc/CC-MAIN-20221003200326-20221003230326-00398.warc.gz"}
https://www.physicsforums.com/threads/how-to-simplify-the-expression-boolean-algebra.808260/	# Homework Help: How to simplify the expression -- Boolean algebra 1. Apr 13, 2015 ### physics=world 1. prove that: X'Y'Z + X'YZ' + XY'Z' + XYZ = (X⊕Y)⊕Z 2. Relevant equations Use postulates and theorems. 3. The attempt at a solution X'Y'Z + X'YZ' + XY'Z' + XYZ (original expression) X'Y'Z + X'YZ' + X(Y'Z' + YZ) (distributive) X'Y'Z + X'YZ' + X.1 (complement) X'Y'Z + X'YZ' + X (identity) need help. also may you expand the expression : (X⊕Y)⊕Z I think it is like this: (XY' + X'Y)(ZXY' +Z'X'Y) but i do not know if it's right 2. Apr 13, 2015 ### BvU Hi, Not familiar with the ' notation, but I suppose X' means $\neg X$ When you expand $(X\oplus Y) \oplus Z$ you just write it out using $(A\oplus B) = A'B + AB'$ twice. For me the easiest part is the second term $(X'Y + XY') Z' = X'Y Z'+ XY' Z'$ which are the 2nd and 3rd in the left hand side of your original staement. Leaves you to prove $(X'Y + XY')' Z = X'Y' Z + XY Z$; not that hard, I hope ?	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9212236404418945, "perplexity": 2858.482710628261}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-30/segments/1531676592475.84/warc/CC-MAIN-20180721090529-20180721110529-00542.warc.gz"}
https://basepub.dauphine.fr/handle/123456789/22780?show=full	dc.contributor.author Rizk, Geovani dc.contributor.author Thomas , A. dc.contributor.author Colin, Igor dc.contributor.author Laraki, Rida HAL ID: 179670 ORCID: 0000-0002-4898-2424 dc.contributor.author Chevaleyre, Yann dc.date.accessioned 2022-02-28T08:57:45Z dc.date.available 2022-02-28T08:57:45Z dc.date.issued 2021 dc.identifier.uri https://basepub.dauphine.psl.eu/handle/123456789/22780 dc.language.iso en en dc.subject graphical bilinear bandit dc.subject.ddc 004 en dc.title Best Arm Identification in Graphical Bilinear Bandits dc.type Communication / Conférence dc.description.abstracten We introduce a new graphical bilinear bandit problem where a learner (or a \emph{central entity}) allocates arms to the nodes of a graph and observes for each edge a noisy bilinear reward representing the interaction between the two end nodes. We study the best arm identification problem in which the learner wants to find the graph allocation maximizing the sum of the bilinear rewards. By efficiently exploiting the geometry of this bandit problem, we propose a \emph{decentralized} allocation strategy based on random sampling with theoretical guarantees. In particular, we characterize the influence of the graph structure (e.g. star, complete or circle) on the convergence rate and propose empirical experiments that confirm this dependency. dc.identifier.citationpages 139:9010-9019 dc.relation.ispartofpublname Proceedings of the 38th International Conference on Machine Learning dc.subject.ddclabel Informatique générale en dc.relation.confdate 2021 dc.relation.confcountry UNITED STATES dc.relation.forthcoming non en dc.description.ssrncandidate non dc.description.halcandidate non dc.description.readership recherche dc.description.audience International dc.date.updated 2022-06-19T22:42:35Z	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.838085949420929, "perplexity": 9169.680217357036}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-14/segments/1679296949331.26/warc/CC-MAIN-20230330132508-20230330162508-00405.warc.gz"}
http://plantsinaction.science.uq.edu.au/content/114-light-and-co2-effects-leaf-photosynthesis	# 1.1.4 - Light and CO2 effects on leaf photosynthesis ## Figp1.06.png Figure 1.6 Photosynthetic response to photon irradiance for a Eucalyptus maculata leaf measured at three ambient CO2 concentrations, 140, 350 and 1000 µmol mol-1. Irradiance is expressed as µmol quanta of photosynthetically active radiation absorbed per unit leaf area per second, and net CO2 assimilation is inferred from a drop in CO2 concentration of gas passing over a leaf held in a temperature-controlled cuvette. CO2 evolution in darkness is shown on the ordinate as an extrapolation below zero. The irradiance at which net CO2 exchange is zero is termed the light compensation point (commonly 15-50 µmol quanta m-2 s-1, shade to sun species respectively). The initial slope of light-response curves for CO2 assimilation per absorbed quanta represents maximum quantum yield for a leaf. (Based on E. Ögren and J.R. Evans, Planta 189: 182-190, 1993) Light impinging on plants arrives as discrete particles we term photons, so that a flux of photosynthetically active photons can be referred to as ‘photon irradiance’. Each photon carries a quantum of electromagnetic (light) energy. In biology the terms photon and quantum (plural quanta) tend to be used interchangeably. CO2 assimilation varies according to both light and CO2 partial pressure. At low light (low photon irradiance in Figure 1.6) assimilation rate increases linearly with increasing irradiance, and the slope of this initial response represents maximum quantum yield (mol CO2 fixed per mol quanta absorbed). Reference to absorbed quanta in this expression is important. Leaves vary widely in surface characteristics (hence reflectance) as well as internal anatomy and chlorophyll content per unit leaf area. Therefore, since absorption of photosynthetically active quanta will vary, quantum yield expressed in terms of incident irradiance does not necessarily reflect the photosynthetic efficiency of the mesophyll. In the case of comparisons between sun and shade leaves, it has led to a widely held but mistaken belief that shade leaves (thinner and with higher chlorophyll content) are more efficient. Expressed in terms of absorbed quanta, sun and shade leaves have virtually identical quantum efficiencies for CO2 assimilation. Assimilation rate increases more slowly at higher irradiances until eventually a plateau is reached where further increases in irradiance do not increase the rate of CO2 assimilation (Figure 1.6). Chloroplasts are then light saturated. Absolute values for both quantum yield and light-saturated plateaux depend on CO2 concentration. Quantum yield increases as CO2 concentration increases as it competes more successfully with other species such as oxygen, at the binding site on Rubisco. Leaf absorptance has a hyperbolic dependence on chlorophyll content. For most leaves, 80–85% of 400–700 nm light is absorbed and it is only in leaves produced under severe nitrogen deficiency where there is less than 0.25 mmol Chl m–2 that absorptance falls below 75%. The plateau in Figure 1.6 at high irradiance is set by maximum Rubisco activity. With increasing CO2 partial pressure, the rate of carboxylation increases. The transition from light-limited to Rubisco-limited CO2 assimilation as irradiance increases becomes progressively more gradual at higher CO2 partial pressures. In part, this gentle transition reflects the fact that a leaf is a population of chloroplasts which have different photosynthetic properties depending on their position within that leaf. As discussed above, the profile of photosynthetic capacity per chloroplast changes less than the profile of light absorption per chloroplast (Figure 1.4). This results in an increase in CO2 fixed per quanta absorbed with increasing depth. A transition from a light to a Rubisco limitation therefore occurs at progressively higher incident irradiances for each subsequent layer and results in a more gradual transition in the irradiance response curve of a leaf compared to that of a chloroplast. Photosynthetic capacity of leaves varies widely according to light, water and nutrient availability and these differences in capacity usually reflect Rubisco content. Leaves in high light environments (‘sun’ leaves) have greater CO2 assimilation capacities than those in shaded environments and this is reflected in the larger allocation of nitrogen-based resources to photosynthetic carbon reduction (PCR cycle; Section 2.1). Sun leaves have a high stomatal density, are thicker and have a higher ratio of Rubisco to chlorophyll in order to utilise the larger availability of photons (and hence ATP and NADPH). Shade leaves are larger and thinner, but have more chlorophyll per unit leaf dry weight than sun leaves. They can have a greater quantum yield per unit of carbon invested in leaves, but with a relatively greater allocation of nitrogen-based resources to photon capture, shade leaves achieve a lower maximum rate of assimilation. Despite such differences in leaf anatomy and chloroplast composition, leaves sustain energy transduction and CO2 fixation in an efficient and closely coordinated fashion. Processes responsible are discussed below (Section 1.2).	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.81532883644104, "perplexity": 4349.096734509156}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-43/segments/1508187824225.41/warc/CC-MAIN-20171020135519-20171020155519-00414.warc.gz"}
https://www.thestudentroom.co.uk/showthread.php?t=4537726	# What is momentum Watch Announcements #1 I understand conservation of momentum and equations related to it, but what is the very nature of it? I am speaking in regards to GCSE physics 0 4 years ago #2 This is a very good question, I hope you are thinking of pursuing physics further? I'm going to try and answer you question as best I can, but if I say something you don't understand/you think might be wrong please just say and I'll try and explain it better! Okay so in terms of newton's laws: "Newton's second law of motion states that the change in linear momentum of a body is equal to the net impulse acting on it" (Wikipedia). This is another way of saying that momentum is a property that can only be changed by the action of a force. In other words, you have to do work (have you done work/energy yet?) to change momentum, so it can be thought of being a bit like kinetic energy, in that it is a property that cannot be created or destroyed, and any gain in momentum by one object, much equal a loss in momentum by another object. This is not a rigorous definition, because momentum and energy are actually fundamentally different things. More generally, linear momentum is the manifestation of a much more complex concept called 'translational symmetry of space time.' Now this is something I don't actually know anything about myself (I'm in my second year of doing physics at uni so by no means an expert), however from a quick read of the wikipedia article, I'll try and explain it :P. Basically this means that the laws of physics are the same everywhere, i.e. the rules that govern our universe don't change depending on where you are. However this is far too complex for me to understand so probably will confuse you as well. 2 4 years ago #3 I think the explanation by Darth_Narwhale is very accurate, detailed and high power, which might be good for the clever GCSE student that ra1500 seems to be. If I were to answer your question, especially considering you are only doing GCSE (and my highest knowledge is only as a minor subject [Medical Physics] as a medical student), I would (and ONLY could!) put it more simply as below: Think of momentum as the tendency of a moving object to carry on moving further in the direction it is moving, and if it were to collide with another object, to "push" it in the direction of the first object, or, if the momntum of the second object is in a different direction and is greater than the momentum of the first object, then for the second object to push the first object. You can imagine that if a rugby player (probably a massive guy) collided into a netball player (probs a much smaller girl!!), it is likely the two together will move in the same direction as the rugby player - this explains why momentum has m (mass) as one item in its calculation. Secondly, take two identical cars A and B (of the same weight) moving in opposite directions. If car A was moving East at 70mph and car B was moving West at 10mph, and they collide head on, surely it is essy to work out that the two will after the collision be more likely to move Eastwards [because the momentum of the faster car would be greater i.e. the tendency of the two cars to move eastwards will be greater than the tendency for them to move westwards) This explains the second variable v (velocity) in the calculation of momentum. In a way, momentum is the opposite of inertia. (inertia is the tendency of an object to stay put where it is and not to move). Hope this helps further. Mukesh (science tutor) 1 4 years ago #4 Momentum does not actually exist as a physical force or object. It is simply the product of mass and velocity of an object. Much like gravity, gravity itself does not exist, it's just the result of mass in space. 0 4 years ago #5 Answering what momentum is is a very difficult question, especially sticking to GCSEs, so I will try and go a little bit further. Intuitively, momentum is a sort of measure of how hard it is stop something. The more momentum the object has, the longer you have to apply a force, or the larger that force will be. This is Newton's second law. But this intuition fails when it comes to fields. Fields (like the gravity field or the electric field) and waves can have momentum, yet you can't stop a field. Actually what does it even mean to stop a field? So basically momentum must have some other definition. Perhaps "the ability to change the motion of other objects" works. A field transfers its momentum to accelerate a particle and waves do the same. Of course this definition is really vague; we need to concretise it. Objects carrying momentum can transfer that momentum to other objects by exerting a force. As long as they are moving they can exert a force, and the heavier they are, the more force they can exert. This prompts one to define momentum as mv. Note that this definition implies conservation of momentum . What I'm trying to say is that momentum is simply a mathematical aide in calculations which does not have a physical representation like distance or speed. As succinctly put by AishaGirl: (Original post by AishaGirl) Momentum does not actually exist as a physical force or object. It is simply the product of mass and velocity of an object. Ultimately, it is just the product of mass and velocity, which is something that just so happens to be useful, because it is conserved so we retain it and give it a name. If you want to delve deeper, momentum becomes a lot of things. In fact you can show that if energy is to be conserved, "something else" must be conserved, and that "something else" is called the momentum. The reason why energy has to be conserved is that the laws of physics don't change with time, so "something" must remain the same, and that "something" is energy. Based on this definition of momentum, you can show that if you took very small changes in kinetic energy, and divided that by the velocity and then summed them all, the resultant is the momentum. (if you are doing addmaths, what I'm saying here is that the integral of the reciprocal of velocity with respect to the kinetic energy is the momentum.). Then the next question is what is energy? By the way the process I'm describing is totally backwards: historically, the concept of momentum came first, then energy. But conceptually, this is better. Now energy is something else where are definitions are arbitrary. In fact, the energy and the momentum share very intricate relationships, which ultimately boil down to this: the laws of physics are the same regardless of your velocity (if constant). Thus no law can tell you whether you truly are moving or not, provided you have constant speed. This is known as the principle of relativity, from Galileo. It is a very powerful principle, and ultimately it describes the momentum and the energy, which describes the forces. Therefore, it is at the roots of all laws. In conclusion, momentum is basically a quantity that is defined as the thing that is conserved because energy is conserved, and energy is this conserved thing that arises from the laws of physics being constant in time, and constant in velocity. 0 4 years ago #6 (Original post by Darth_Narwhale) This is not a rigorous definition, because momentum and energy are actually fundamentally different things. More generally, linear momentum is the manifestation of a much more complex concept called 'translational symmetry of space time.' Now this is something I don't actually know anything about myself (I'm in my second year of doing physics at uni so by no means an expert), however from a quick read of the wikipedia article, I'll try and explain it :P. Basically this means that the laws of physics are the same everywhere, i.e. the rules that govern our universe don't change depending on where you are. However this is far too complex for me to understand so probably will confuse you as well I'll try and explain it. Consider a quantity L = K - U, where K is the kinetic energy and U the potential energy. A fundamental law in (classical) physics says that for each coordinate, if you differentiate L with respect to the velocity in that coordinate's direction, then differentiate that with respect to time, that's the same as differentiating L with respect to that coordinate. Because the potential energy does not depend on the speed (in general), the time derivative of dL/dx' is the time derivative of dK/du, which is mx', the momentum. And since the potential is defined as ∫-Fdx, and the since the kinetic energy does not depend on position, dL/dx is just F. So basically: where I replaced the x' by v so that the law stands out better. This is Newton's 2nd law. Now suppose that for one coordinate, dL/dx = 0, so that L does not depend on that coordinate. Then the right hand side becomes zero, and you have an equation telling you that the momentum in that direction is conserved. Since the derivative L is zero, this means that L does not change if you moved your entire system along that coordinate. This implies that the system behaves the same no matter the value of that coordinate: the laws of physics are the same under translation. In fact L is the Lagrangian for classical mechanics, so there is no magnetic field term in there. In the case of a magnetic field, the Lagrangian is no longer K - U, but K - f(v) where f(v) is a function of velocity. You can extend the approach: symmetry under rotation is angular momentum, and symmetry under time shifts is energy, albeit this one is a bit harder to show. 1 4 years ago #7 (Original post by dbs1984) I'll try and explain it. Consider a quantity L = K - U, where K is the kinetic energy and U the potential energy. A fundamental law in (classical) physics says that for each coordinate, if you differentiate L with respect to the velocity in that coordinate's direction, then differentiate that with respect to time, that's the same as differentiating L with respect to that coordinate. Because the potential energy does not depend on the speed (in general), the time derivative of dL/dx' is the time derivative of dK/du, which is mx', the momentum. And since the potential is defined as ∫-Fdx, and the since the kinetic energy does not depend on position, dL/dx is just F. So basically: where I replaced the x' by v so that the law stands out better. This is Newton's 2nd law. Now suppose that for one coordinate, dL/dx = 0, so that L does not depend on that coordinate. Then the right hand side becomes zero, and you have an equation telling you that the momentum in that direction is conserved. Since the derivative L is zero, this means that L does not change if you moved your entire system along that coordinate. This implies that the system behaves the same no matter the value of that coordinate: the laws of physics are the same under translation. In fact L is the Lagrangian for classical mechanics, so there is no magnetic field term in there. In the case of a magnetic field, the Lagrangian is no longer K - U, but K - f(v) where f(v) is a function of velocity. You can extend the approach: symmetry under rotation is angular momentum, and symmetry under time shifts is energy, albeit this one is a bit harder to show. Thanks, this is a brilliant explanation. We are actually doing a classical dynamics lecture course atm, and have literally just covered this, but your wording is very clear. 1 4 years ago #8 (Original post by ra1500) I understand conservation of momentum and equations related to it, but what is the very nature of it? I am speaking in regards to GCSE physics An older term for momentum was simply "motion". Momentum is the quantity that tells you how much motion there is in a system, in some sense. Intuitively, a mass of 1 kg moving in a straight line at 1 m/s has less "motion" than a mass of 1 kg moving in a straight line at 10 m/s. However, a mass of 10 kg moving in a straight line at 1 m/s has the same amount of motion as 10 1 kg masses moving in a straight line at 1 m/s - that's because we can imagine the 10 kg mass as 10 1 kg masses stuck together. However, we also need to take direction into account. Consider the following experiment. You are floating in space with two 1 kg masses. You are in the centre of a large, stationary, rectangular metal box. You push the two masses at the same time with the same speed towards opposite ends of the box. By symmetry, when the masses collide with the walls of the box, you expect it to remain at rest. From the outside of the box, an observer sees a box at rest, and says that the system has no motion at any time. Inside the box, you see two identical masses moving with the same speed in opposite directions. You must conclude that the two moving masses have no total motion, even though each has an individual motion. We can also reason about motion using other thought experiments. Imagine you are an observer watching two lumps of clay of mass travel towards each other at speed . When they collide, they stick together to form a lump of mass . By symmetry, it must be at rest relative to you. Now imagine a lump of clay of mass moving at towards an identical lump of clay. When they collide, they move off relative to you at some speed . However, an observer moving in the same direction as the moving mass sees a mass moving at speed towards a mass moving at speed in the opposite direction i.e. she sees the original situation. So from her POV, the combined mass is stationary after collision, which from your POV means that it moves with speed (the same as the moving observer). If we now tot up the quantities mass x velocity before and after collision, we find that they are the same (. Arguments like this allow you to conclude that the "motion" in a system is conserved by collisions, if we define motion = mass x velocity (But of course, you need to do experiments to find out if the universe agrees with your reasoning - this is physics, not abstract maths). These days we call it "momentum", of course. 1 4 years ago #9 (Original post by atsruser) An older term for momentum was simply "motion". Momentum is the quantity that tells you how much motion there is in a system, in some sense. Intuitively, a mass of 1 kg moving in a straight line at 1 m/s has less "motion" than a mass of 1 kg moving in a straight line at 10 m/s. However, a mass of 10 kg moving in a straight line at 1 m/s has the same amount of motion as 10 1 kg masses moving in a straight line at 1 m/s - that's because we can imagine the 10 kg mass as 10 1 kg masses stuck together. However, we also need to take direction into account. Consider the following experiment. You are floating in space with two 1 kg masses. You are in the centre of a large, stationary, rectangular metal box. You push the two masses at the same time with the same speed towards opposite ends of the box. By symmetry, when the masses collide with the walls of the box, you expect it to remain at rest. From the outside of the box, an observer sees a box at rest, and says that the system has no motion at any time. Inside the box, you see two identical masses moving with the same speed in opposite directions. You must conclude that the two moving masses have no total motion, even though each has an individual motion. We can also reason about motion using other thought experiments. Imagine you are an observer watching two lumps of clay of mass travel towards each other at speed . When they collide, they stick together to form a lump of mass . By symmetry, it must be at rest relative to you. Now imagine a lump of clay of mass moving at towards an identical lump of clay. When they collide, they move off relative to you at some speed . However, an observer moving in the same direction as the moving mass sees a mass moving at speed towards a mass moving at speed in the opposite direction i.e. she sees the original situation. So from her POV, the combined mass is stationary after collision, which from your POV means that it moves with speed (the same as the moving observer). If we now tot up the quantities mass x velocity before and after collision, we find that they are the same (. Arguments like this allow you to conclude that the "motion" in a system is conserved by collisions, if we define motion = mass x velocity (But of course, you need to do experiments to find out if the universe agrees with your reasoning - this is physics, not abstract maths). These days we call it "momentum", of course. I thought momentum was a fictitious force, much like gravity... https://www.scientificamerican.com/a...titious-force/ I don't know I think whether certain forces are actually real or not is a philosophical debate. Correct me if I'm wrong though. 0 4 years ago #10 (Original post by AishaGirl) I thought momentum was a fictitious force, much like gravity... Momentum isn't a force at all, so this doesn't make much sense, I'm afraid. A force is what acts on a body when its momentum is changing, and the size of the force in Newtons is equal to the rate of change of that body's momentum. I don't know I think whether certain forces are actually real or not is a philosophical debate. Correct me if I'm wrong though. I'm not sure I really understand the question. However, generally in physics "real" forces are produced by interactions between bodies e.g. due to the EM field, and they come in Newton III force pairs. "Fictitious" forces have to be invented when a system is viewed from a non-inertial frame e.g. one that is accelerating. For example, consider a ice hockey puck mass tied to a post in the ice with a spring, and made to move in a circle on the ice. From the POV of an observer who is not rotating relative to the pole, we say that the puck is accelerating with magnitude v^2/r towards the pole and consequently a force acts on it towards the pole of size mv^2/r. The force is due to the stretching of the spring, and we call it centripetal force. From the POV of an observer rotating at the same rate as puck and in the same sense, then the puck is not moving at all. However, she can see that the stretched spring is pulling on it, so by Newton II it should accelerate. To ensure that Newton's laws still make sense in her rotating frame, she has to invent a new force of the same magnitude as the force, in the opposite direction, to "balance" the force of the spring. This appears (to the rotating observer) to be pulling the puck away from the pole, and we call it centrifugal force. However, the centrifugal force doesn't really exist - there is no interaction with a phyiscal body that is causing it - it is merely invented to make sure Mrs Rotating can make Newton's law work from her POV. 0 4 years ago #11 (Original post by Darth_Narwhale) Thanks, this is a brilliant explanation. We are actually doing a classical dynamics lecture course atm, and have literally just covered this, but your wording is very clear. Thanks for the compliment. I'm hoping to teach physics some day, so comments like those show I'm on the right track. 0 X Attached files new posts Back to top Latest My Feed ### Oops, nobody has postedin the last few hours. Why not re-start the conversation? see more ### See more of what you like onThe Student Room You can personalise what you see on TSR. Tell us a little about yourself to get started. ### Poll Join the discussion #### What do you find most difficult about revising? Prioritising what to revise (10) 10.31% Remembering what was covered in lessons (1) 1.03% Finding the time to revise (7) 7.22% Finding the motivation (24) 24.74% Getting distracted (14) 14.43% Procrastination (40) 41.24% Having the tools you need (0) 0% Something else (tell us in the thread) (1) 1.03%	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9174322485923767, "perplexity": 322.4755990784152}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-49/segments/1637964363465.47/warc/CC-MAIN-20211208083545-20211208113545-00312.warc.gz"}
http://mathoverflow.net/questions/44062/computing-pi-1-s1-using-groupoids?sort=votes	Computing $\pi_1 S^1$ using groupoids I believe it is possible to compute $\pi_1 S^1$ by applying the groupoid version of the Seifert-Van Kampen Theorem (in the version presented in May's Concise Course) to a covering of the circle by three arcs. Is there an account like this somewhere in the literature? Ideally I'd like a discussion that a student familiar with May's book would be able to read. (May doesn't take a 2-categorical approach to groupoids, and so he does not discuss the fact that a diagram of groupoids that is a point-wise equivalence induces an equivalence of colimits. This is rather important for computations.) Edit: this last statement is false in general! I was thinking of homotopy colimits. The relevant (correct) fact appears in Ronnie Brown's book: retracts of pushouts are pushouts. This is the means by which one compares the Van Kampen theorem for the full fundamental groupoid - as in May's book - with the Van Kampen theorem for the fundamental groupoid on a set of basepoints.) - The book of Tammo Tom Dieck "Algebraic Topology" takes a related but different approach. – j.c. Oct 29 '10 at 7:09 The isomorphism $\pi_1(S^1)\simeq \mathbf{Z}$ is just a triviality:if we define $S^1$ as the pushout of the diagram of simplicial sets $\Delta^0 \leftarrow \partial\Delta^1\to \Delta^1$, then we see immediately that the set of maps from $S^1$ to the nerve of a groupoid $G$ is simply the set of arrows $x\to y$ in $G$ such that $x=y$. Therefore, the groupoid $\pi_1(S^1)$ is canonically isomorphic to the group $\mathbf{Z}$ (seen as a groupoid with one object), simply because they both share the same universal property. – Denis-Charles Cisinski Nov 14 '10 at 0:13 Denis-Charles, what exactly do you mean by "the groupoid $\pi_1 S^1$"? Are you referring to a combinatorial definition of the fundamental groupoid of a simplicial set? I'm familiar with Kan's combinatorial description of the homotopy groups of a Kan complex, and I guess you could mean something similar? Most importantly, how easy is it to identify this object with the fundamental groupoid of the geometric realization? Milnor's original proof that Kan's homotopy groups agree with the homotopy groups of the realization used the Van Kampen theorem. – Dan Ramras Nov 14 '10 at 6:01 Using the version of Van Kampen in Brown's book, you can even compute the fundamental group of the circle by using a cover with two intervals: just pick one basepoint in each component of the intersection. – Omar Antolín-Camarena Nov 14 '10 at 14:43 Omar, yes that's right! May's book has a seemingly unnecessary connectedness assumption on the intersections of sets in the cover, which is why I was thinking of 3 arcs. – Dan Ramras Nov 14 '10 at 18:10 I can only point to the place where this was originally done (or rather, the latest edition thereof): Topology and Groupoids by Ronnie Brown It's a fantastic textbook and easy to read (and cheap, if you buy the electronic copy - the best £5 I've spent). Ideally what you'd do is calculate the equivalent subgroupoid $\Pi_1(S^1,\{a,b,c\})$ where $a,b,c$ are three points in $S^1$, one in each intersection of opens. - This is what I had in mind. I did look in Chapter 9 of Brown's book (Chap. 9 is free) and didn't see this. (Brown seems to compute $\pi_1 S^1$ in some other way in Corollary 9.1.5; I haven't digested his notation yet, though.) Maybe this argument appears somewhere else? I'll have to get myself the full book, I guess. – Dan Ramras Oct 29 '10 at 5:50 Actually this isn't how he computes it, but it should be possible to do so. – David Roberts Oct 29 '10 at 5:52 I second David's recommendation. – jd.r Oct 29 '10 at 11:33 Chapter 6 is the place to look, not Chapter 9. – Dan Ramras Nov 13 '10 at 20:59 A rather belated comment on these! I like the comparison between the circle $S^1$ as obtained from the unit interval $[0,1]$ by identifying $0$ and $1$ in the category of spaces, and the group of integers $\mathbb Z$ as obtained from the groupoid $\mathcal I$, which has objects $0$ and $1$ and exactly one arrow $\iota:0 \to 1$, by identifying $0$ and $1$ in the category of groupoids. I got hold of the idea in the 1960s from writing the first edition of this book that all of 1-dimensional homotopy theory was better expressed in terms of groupoids rather than groups This led to the question: are groupoids useful in higher homotopy theory? Is the 1-dimensional case a one-off''? or not? I liked the more exciting prospect, but it took 9 years to get with Philip Higgins in 1974 a good definition in dimension 2, namely the homotopy double groupoid of a pair of spaces, and a 2-dimensional van Kampen theorem. - Further comment: although I was attracted by the retraction argument, it turned out that it did not work easily for any family of open sets, and did not work in higher dimensions. So I returned to the original argument of Crowell and this is given in the paper: R.Brown and A. Razak, A van Kampen theorem for unions of non-connected spaces'', Archiv. Math. 42 (1984) 85-88, which also gives the best possible connectivity condition, that the set $A$ of base points meets each path component of each $3$-fold intersections of the cover. This is related to the Lebesgue Covering Dimension. – Ronnie Brown Jan 13 '13 at 22:19 I also prefer, contrary to Gramain and other authors, to give a proof by verification of the required universal property, rather than relying on a specific construction of a pushout, or colimit, of groups, or groupoids. One reason is to have a proof which generalises to higher dimensions, given the appropriate gadget, and so obtain new results and methods in homotopy theory. – Ronnie Brown Nov 8 '13 at 18:33 The reference to Brown is probably the best one for the moment. Unfortunately, May's book doesn't seem to be so useful because, even in the theorem about groupoids, there is a connectedness assumption on the interesections of the open sets covering the space. Moreover, once one has a general pushout theorem for groupoids, one needs to know how to compute the isotropy groups of the given groupoid, which May doesn't explain. André Gramain has written a short account of that, Le théorème de van Kampen. For a good space, the theory of coverings gives an equivalence of category between coverings and sets with an action of the fundamental group. (This determines the group.) This gives various way of computing the fundamental group(oid) of a space via descent theory. In the setting of schemes, Grothendieck gives the relevant theorems and formulae in a few lines in SGA 1. I can phrase Denis-Charles's answer above in a slightly more elementary way, using the formulation via coverings. The circle $S^1$ is the interval $[0,1]$ with endpoints attached; therefore, a covering of $S^1$ can be described as a covering of $[0,1]$ together with an identification of the fibers at $0$ and $1$. We thus have a covering $A\times [0,1]$, with a bijection of $A\times\{0\}$ with $A\times\{1\}$. That is, a set $A$, with a bijection of~$A$. That is, a set $A$ with an action of the group $\mathbf Z$. So $\pi_1(S^1)=\mathbf Z$. - May's path connectedness assumption seems to be unnecessary. I don't see anywhere in his proof that path connectedness is used (am I missing something?). The covering space perspective sounds a lot like the way Quillen computed the fundamental group of the Q-construction. – Dan Ramras Nov 14 '10 at 18:10 It is indeed unnecessary. But the computation of the isotropy groups of pushouts is definitely lacking without the assumption... – ACL Nov 14 '10 at 23:50	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9024298787117004, "perplexity": 265.67544851811516}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-18/segments/1461860122501.61/warc/CC-MAIN-20160428161522-00114-ip-10-239-7-51.ec2.internal.warc.gz"}
http://www.ntg.nl/pipermail/ntg-context/2004/007509.html	# [NTG-context] \presentationstep Mon Nov 8 13:59:49 CET 2004 At 19:57 -0500 7/11/04, David Munger wrote: >Oh sorry for not being clear about it. I was assuming that some >presentation module would be imported, for instance: >\usemodule[pre-original] > >So probably there lacks a \page command in your \Subject definition. > >About the $and$: you're right. I was using the amsl module from >Giuseppe Bilotta. > > > >So, assuming that the steps code is in a file name t-rsteps.tex, the >complete example would be: > >---------------------------------------------------------- > >\usemodule [pre-original] >\usemodule [rsteps] Hi David, Thanks for the details. Indeed I get now what is expected from your macros, and as a matter of fact the result is much much better than that of my crude macros... You did a great improvement! So I am going to use yours from now on: thanks again! If I can suggest a possible improvement to the t-rsteps.tex macros, it is the following: When one uses these macros with an automatic numbering such as \placeformula[equation-reference] (see the example below), with each invocation of \page (that is a step) the number increases, and this is an unwanted side result. Would it possible to "freeze" the numbering procedure in such a way that the number doesn't change in each step? (When I was using my macros, I didn't use \placeformula in sildes with steps, but rather an old \leqno from plain TeX). Best regards: OK %%%%%%%%%%%%%%%%%%%%%%% example steps-david-2.tex \usemodule [pre-original] \usemodule [rsteps] \starttext \StartSteps[Slide Title] % the title is passed to % the \Subject macro defined in pre-original \startitemize \FromStep[1] {\item {\bf Lemma. } {\it For any $u,v \in H$, a Hilbert space, we have the following Cauchy-Schwarz inequality\/} \placeformula[Cauchy-Schwarz] \startformula \|(u\|v)\| \leq \Vert u\Vert \cdot \Vert v \Vert. \stopformula} \FromStep[2] {\item {\bf Proof. } Consider $f(t):= (u+tv\|u+tv)$ for $t\in {\Bbb C}$.} \FromStep[3]{\item We have $f(t) \geq 0$ for all $t\in {\Bbb C}$.} \stopitemize \StopSteps \stoptext %%%%%%%%%%%%%%%%%% end example steps-david-2.tex	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 2, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.985212504863739, "perplexity": 4689.550562337154}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-42/segments/1413507444657.46/warc/CC-MAIN-20141017005724-00291-ip-10-16-133-185.ec2.internal.warc.gz"}
http://www.astroexplorer.org/details/apjlab380df4	Image Details Choose export citation format: On the Diversity of Fallback Rates from Tidal Disruption Events with Accurate Stellar Structure • Authors: E. C. A. Golightly, C. J. Nixon, and E. R. Coughlin 2019 The Astrophysical Journal Letters 882 L26. • Provider: AAS Journals Caption: Figure 4. Fallback rate onto the 106M SMBH in units of Solar masses per year as a function of time in years. Here solid curves correspond to the density profiles generated from MESA, dashed curves are γ = 5/3 polytropes matched to the stellar mass and radius of the MESA star, and dotted–dashed curves are γ = 1.35 polytropes matched to the MESA star mass and radius; dotted black lines show the power-law ∝ t−5/3, while the dotted–dotted–dashed line in the bottom-right panel shows the scaling ∝ t−9/4. The long-dashed black line gives the Eddington luminosity of the BH, assuming a radiative efficiency of 10% and an electron-scattering opacity of 0.34 cm2 g−1. The specific star is shown by the name in the legend, and panels on the left side show the fallback from stars at ZAMS, while those on the right are more highly evolved. It is apparent from the top-left and middle-left panels that the fallback curves from the 0.3 M, ZAMS and the 1 M, ZAMS progenitors are very well-reproduced by γ = 5/3 and γ = 1.35 polytropes, respectively. Every other fallback curve from a MESA-generated density profile, however, shows significant deviations from the polytropic approximations. We also see that the 3.0 M, MAMS follows ∝ t−9/4 at late times, which results from the presence of a bound core that survives the encounter (Coughlin & Nixon 2019; no bound core is left when the star is modeled as a polytrope). The 0.3 M, MAMS MESA star also shows enhanced variability in the fallback rate, which arises from the fact that the stream—unlike the polytropic models for the same MESA star mass and radius—has fragmented vigorously into small-scale clumps.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8542385697364807, "perplexity": 3153.3196277419324}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-29/segments/1593655886706.29/warc/CC-MAIN-20200704201650-20200704231650-00425.warc.gz"}
http://math.stackexchange.com/questions/30532/whats-the-smallest-positive-integer-made-of-1s-that-is-divisible-by-a-number-m	# What's the smallest positive integer made of 1's that is divisible by a number made out of 100 9's I was asked what is the smallest positive integer made of ones (11111...1) that is divisible (no reminder) by a number made up of 100 digits of 9 (9999...9). I noticed that for 9 the smallest integer made out of ones that will divisible by him, is 111 111 111 (9 digits), and that for 99 the integer will be with 111 111 111 111 111 111 (92 digits). From this I assume that the answer will be 9100 digits of 1. So my question is first is this true and second how can I prove it. Thanks. - Do you mean THE number made by 100 digits of 9? – quanta Apr 2 '11 at 16:28 Hint: Divisibility by the number which has 100 digits of 9 is equivalent to divisibility by 9 and by the number which has 100 digits of 1 (since casting-out-nines shows these are coprime). Now apply these restrictions to a number that is a string of 1's. – hardmath Apr 2 '11 at 16:36 ## 1 Answer Hint: express the chain of $k$ $1$'s as $\frac{10^n-1}{9}$ (how do $k$ and $n$ relate?) and the $9$'s similarly, and think of factoring them. - Thanks :-) I get it now. – user9014 Apr 2 '11 at 17:23	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6071496605873108, "perplexity": 376.5903676360858}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-22/segments/1432207928019.82/warc/CC-MAIN-20150521113208-00190-ip-10-180-206-219.ec2.internal.warc.gz"}
http://crypto.stackexchange.com/users/351/d-w?tab=activity&sort=comments&page=13	# D.W. less info reputation 32063 bio website location age member for 2 years, 8 months seen 1 hour ago profile views 427 Aug28 comment Generate Elliptic Curve Private Key from User Passphrase? If have a way to keep data secret from an attacker but ensure it is known to authorized users, then don't mess around with passwords or salts or anything: just use a cryptographic key that is known to authorized users but not available to attackers. On the other hand, if you don't have a way to do that, then no amount of additional salt (that's known to the attacker) will change any of my bottom line conclusions. Aug27 comment RC2, RC4, RC5 key length Thanks, @Thomas, that's a good suggestion! I made the edit you suggested. Aug26 comment RC2, RC4, RC5 key length Brownbat, nice, I like it. +1. Aug26 comment Lagrange Interpolation for finite field GF(2^8), for Secret Reconstruction This question appears to be off-topic because it is about code review. Code review is out of scope for this site; see meta.crypto.stackexchange.com/q/303/351. Aug25 comment Generating an IV for ESP 3DES-CBC I don't recommend using /dev/random, for a number of reasons (do a search here or on IT Security.SE to see why). Instead, use /dev/urandom or any crypto-quality pseudorandom number genreator. Aug25 comment Is there any research about cryptography on nondeterministic Turing machines? [..] Also, w.h.p, the real key $K$ is the only key that fulfills all of these requirements, since there are about $2^{1780380}$ such input sequences and only about $1/2^{1000000}$ of them are consistent with the known keystream and only about $(1-1/e)^{1185858}=1/2^{784715}$ of the remainder pass the rest of the tests. Therefore, this attack will find the real key $K$ and output it. Aug25 comment Is there any research about cryptography on nondeterministic Turing machines? Here's an attack that breaks your scheme. Suppose we have 1000000 bits of known (debiased) keystream. Guess $K$. Guess a 1876000-bit sequence containing at most 690142 0's; it is a possible input to the von Neumann debiaser. Test whether applying von Neumann debiasing to this yields the known keystream; reject if not. Guess $M_i$ for each position $i$ where this sequence has a 1 bit. Test whether $H(K,N,i,M_i)=0$ for each such $i$; reject if not. If all tests pass, accept and output $K$. w.h.p, the debiaser only needed $\le 1876000$ bits of input, and at most 690142 in its input were 0's. [..] Aug23 comment what is pairing in cryptography? What reading have you done? What effort have you made? Have you looked in Wikipedia? Have you looked in modern textbooks? Have you searched via Google? Have you read course notes on the topic? We expect you to do some investigation on your own before asking here: ask only questions that you actually care about -- and if you care about it, do a little research on your own. In this case, it is very easy to find basic information on pairings (e.g., on Wikipedia). Aug23 comment The specification of modern, non-communicating cipher machinery These questions all seem pretty standard, for applied cryptography. Have you read Cryptography Engineering, by Ferguson, Schneier, and Kohno? Or other good textbooks on applied cryptography? They'll tell you about things like how long your IV should be, why you need a message authentication code, how to resynchronize after corruption, etc. You should start by studying what is already known about computer-based systems, then analyze for yourself how they apply to your situation, and come back if there's anything that you can't work out from the standard references. Aug22 comment Create a field in PBC What you want to do has nothing to do with pairing-based cryptography. Why would you want to use PBC, or something related to pairings? Aug22 comment Is there any research about cryptography on nondeterministic Turing machines? @PaŭloEbermann, thank you, yes, that's a good summary (with the caveat that you have to be able to verify whether your guess was correct or not). Aug22 comment Is a 1024-bit DSA key considered safe? @bdesham, sorry, I don't know the answer to your second question. I don't know of any way to replace it without revoking it and creating a whole new key, but maybe someone else will know. Aug22 comment How can I accomplish Key Derivation in JavaScript? @AbhiBeckert, If you want advice on how to get the best possible security for your web service, I recommend you ask a question that describes your web service, your security needs, your requirements, your user population, and similar information. We can't read your mind; and it's hard to provide a useful answer without that information. As it is, I can only answer the question you asked (whether it's possible to take a weak password and turn it into a strong crypto key); the answer is no, you can't. It doesn't matter how inconvenient that answer is for users; the answer remains correct. Aug21 comment How resilient to attackers with extreme resources available is this encryption method? @Everlag, the short answer is you can't: you need to rely upon something more than just a passphrase. The simple answer is to use public-key key exchange as others have suggested (e.g., like SSL). Or, maybe you need secure storage somewhere (where the private key can be stored securely; possibly encrypted under the passphrase); maybe you need a hardware device or token or smartcard; maybe you need something else. It's hard to tell you what the best approach will be, without knowing anything of the application requirements or restrictions or goals beyond that you want very strong cryptography. Aug21 comment Understanding the “cube-root math” behind an RSA signature forgery hlh, sorry, I don't understand your question. The paper explains why the answer is $2^{1019} - (N * 2^{34}/3)$. They've already given you this answer (magically) and are now explaining how you can verify that this answer is correct. Plug in $A=2^{1019}$, $B=N2^{34}/3$ into (7), exactly as the paper tells you do, and then simplify, and then the paper tells you why the cube of $2^{1019} - (N 2^{34}/3)$ is $2^{3057}-N*2^{2072}+G$. Aug21 comment Strength of CBC with Ciphertext Stealing This doesn't really answer the OP's question, which was about the degree of risk due to leaking the length. This is the one respect in which CBC-CTS does not achieve the same level of security as plain CBC, as CBC-CTS leaks more precise information about the plaintext length. Aug21 comment Understanding the “cube-root math” behind an RSA signature forgery The paper explains how it got this number immediately after the expression you are quoting. See equations (7) and (8) and the surrounding text (continuing onto the top of the next page). Aug20 comment Is there any research about cryptography on nondeterministic Turing machines? "You appear to assume that if there is no such path, you don't get any usable output" - Yes, that's right. I agree: that's exactly the heart of it. See my comment on the question, where I asked for clarification about what the original poster (user8007) had in mind in this regard. I'm going based upon my best attempt at interpreting user8007's answer as well as my limited understanding of complexity theory. Do you know of any reference which suggests which is the right formulation? If so, can you share a reference where I can learn more? I'd love to learn more! Aug20 comment Is there any research about cryptography on nondeterministic Turing machines? (cont.) It is easy to find a condition under which Bob accepts and outputs that $i=1$, but no amount of non-determinism is enough for Bob to accept and output that $i=0$. (There's no single guess that lets Bob verify that there is no solution to your equation. If Bob guesses one value of $M$ and find it isn't a solution to the equation, he has no idea whether some other value of $M$ might be a solution.) Encryption has the same problem. So, your example is not valid: neither encryption nor decryption can be computed using a non-deterministic algorithm. Aug20 comment Is there any research about cryptography on nondeterministic Turing machines? Oops, forget everything I wrote earlier! I just figured out what I missed. Your example is no good because Bob cannot decrypt. Try writing out a non-deterministic algorithm Bob can use to decrypt. To see this, just try writing a non-det. algorithm Bob can use to compute a single biased bit $i$. Make sure you remember the rules of non-deterministic algorithms: you have to specify the criteria under which Bob accepts or rejects. What is the condition under which Bob accepts and outputs that $i=0$ (that there is no solution $M$)? Try to write it down -- you'll see you are stuck. (cont.)	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4850216805934906, "perplexity": 850.8643621187831}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-15/segments/1398223206120.9/warc/CC-MAIN-20140423032006-00659-ip-10-147-4-33.ec2.internal.warc.gz"}
https://brilliant.org/problems/3-variables-2-equations-1-answer/	# 3 variables, 2 equations, 1 answer $\large x + y = z^2\\ \large x^2 + y^2 = z^3$ If positive integral solutions $$(x_1, y_1, z_1), (x_2, y_2, z_2), \ldots, (x_n, y_n, z_n)$$ satisfy the system of equations above, find the value of $\large \displaystyle \sum_{i=1}^n (x_i + y_i + z_i)$ ×	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9989035725593567, "perplexity": 737.6188423813197}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-13/segments/1490218189802.72/warc/CC-MAIN-20170322212949-00516-ip-10-233-31-227.ec2.internal.warc.gz"}
https://tex.stackexchange.com/questions/332771/horizontal-rule-line-below-the-address-in-letter	# Horizontal rule/line below the address in letter I am new in this community with a problem. I am writing a cover letter. I need to have a horizontal rule/line that expands through left to right of page just below the email address (above the date). Any solution will be highly appreciated. Also I am not sure which command is providing date in the letter. I don't find any date command in the preamble. Thanking you so much. Below is the MWE: \documentclass[11pt]{letter} \topmargin = -1.5in % Make letterhead start about 1 inch from top of page \textheight = 10.4in % text height can be bigger for a longer letter \oddsidemargin = 0pt % leftmargin is 1 inch \textwidth = 6.8in % textwidth of 6.5in leaves 1 inch for right margin \usepackage{hyperref} \usepackage{graphicx} \usepackage{lipsum} %%% XXXX \\ SH, OH, USA \\ Phone: XXXXX \\ Email: [email protected]} \vfill % forces letterhead to top of page \longindentation = 0pt \begin{document} \begin{letter} {Chair, Search Committee \\ Department of XXX \\ YYYY University \\ Subject: XXXX, Faculty Position} \opening{Dear Search Committee Chair,} Body of the letter first line \\ \vdots \\ Body of the letter last line \\ \closing{Sincerely \\[3mm] \fromname{Money Tota} } \encl{(i) My CV, (ii) XXX, and (iii) YYY} \end{letter} \end{document} • Thank you so much. It is working as mentioned. However, I really need a thicker line that matches with the text width (here 6.8in) instead of the width of whole page. – Money Tota Oct 7 '16 at 20:49 Something like this?? Note I set the date that appears by redefining \today to {4 July 1776}. \documentclass[11pt]{letter} \topmargin = -1.5in % Make letterhead start about 1 inch from top of page \textheight = 10.4in % text height can be bigger for a longer letter \oddsidemargin = 0pt % leftmargin is 1 inch \textwidth = 6.8in % textwidth of 6.5in leaves 1 inch for right margin \usepackage{hyperref} \usepackage{graphicx} \usepackage{lipsum} \usepackage{stackengine} %%% XXXX \\ SH, OH, USA \\ Phone: XXXXX \\ Email: [email protected]\bclap[5pt]{\makebox[2.5\textwidth]{\hrulefill}}} \vfill % forces letterhead to top of page \longindentation = 0pt \renewcommand\today{4 July 1776} \begin{document} \begin{letter} {Chair, Search Committee \\ Department of XXX \\ YYYY University \\ Subject: XXXX, Faculty Position} \opening{Dear Search Committee Chair,} Body of the letter first line \\ \vdots \\ Body of the letter last line \\ \closing{Sincerely \\[3mm] \fromname{Money Tota} } \encl{(i) My CV, (ii) XXX, and (iii) YYY} \end{letter} \end{document} One can change the position of the line through the optional argument of \bclap.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6347391605377197, "perplexity": 9437.4561671615}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-35/segments/1566027314752.21/warc/CC-MAIN-20190819134354-20190819160354-00066.warc.gz"}
https://www.physicsforums.com/threads/force-on-each-wall-of-a-box.74290/	# Force on each wall of a box 1. May 4, 2005 ### jennypear A cubic metal box with sides 32.0 cm contains air at a pressure of 1.00 atm and a temperature of 294 K. The box is sealed so that the volume is constant and it is heated to a temperature of 396K. Find the force on each wall of the box due to the increased pressure within the box. [The outside air is at 1 atm of pressure.] I started out PV=nRT volume of the box = .32^3=0.328m^3(1L/1x10^-3)=32.8L n=PV/RT 1atm(32.8L)/(.08207 atm L/molK)(294K)=1.36mol P=nRT/V [1.36mol(.08207 atm L/molK)396K]/32.8L =1.35 atm F=PA =1.35 atm.32^2=.138 2. May 4, 2005 ### OlderDan There is no need to calculate n, since it is constant, but it is not wrong to do so. Assuming your calculation of the pressure is correct, it looks like you have just neglected to account for the 1atm pressure still on the outside. 3. May 4, 2005 ### jennypear how do you account for that? 4. May 4, 2005 ### OlderDan The pressure on the outside is still 1 atm. It is the pressure difference between inside and outside that produces the net force on the walls. 5. May 4, 2005 ### jennypear so that would be F=deltaPA .35*.32^2=.03584 that came up as incorrect 6. May 4, 2005 ### OlderDan What have you done about units? What are the units of the answer you are trying to find? How do you express one atmosphere in those units? 7. May 4, 2005 ### dextercioby Your whole numerical computations need to be redone,as they're wrong...The volume of the box,for example $$V_{\mbox{box}}=(32\cdot 10^{-2}\mbox{m})^{3}=2^{15}\cdot 10^{-6}\mbox{m}^{3}=32.784\cdot 10^{-6}\mbox{m}^{3}\simeq 32.8\cdot 10^{-3}\mbox{m}^{3}$$ Use SI-mKgs units... Daniel. 8. May 4, 2005 ### FredGarvin Like Dex said...units!!!! Since you are working in SI units, your volume must be in meters and your pressure must be in Pa (n/m^2). Only then will your answer be in Newtons.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5594168901443481, "perplexity": 1473.013094599609}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-50/segments/1480698541361.65/warc/CC-MAIN-20161202170901-00341-ip-10-31-129-80.ec2.internal.warc.gz"}
http://physics.stackexchange.com/users/16281/ryker	# Ryker less info reputation 5 bio website location age member for 2 years seen Oct 22 at 4:56 profile views 11 # 3 Questions 6 Is it possible for $\Delta x$ ($\sigma_x$) of any free particle wave packet to be decreasing at any time? 5 Why doesn't a marble rolling on a table ever reflect back at the edge? 1 If we have a current $I$ flowing down a wire, why must the net bound current be zero? # 165 Reputation +25 Why doesn't a marble rolling on a table ever reflect back at the edge? +30 Is it possible for $\Delta x$ ($\sigma_x$) of any free particle wave packet to be decreasing at any time? +5 If we have a current $I$ flowing down a wire, why must the net bound current be zero? This user has not answered any questions # 4 Tags 0 quantum-mechanics × 2 0 current 0 electromagnetism 0 uncertainty-principle # 8 Accounts Mathematics 484 rep 315 Academia 166 rep 5 Physics 165 rep 5 Mathematica 145 rep 5 Philosophy 111 rep 4	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5386888980865479, "perplexity": 1336.0918872362456}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-52/segments/1418802765002.8/warc/CC-MAIN-20141217075245-00056-ip-10-231-17-201.ec2.internal.warc.gz"}
https://worldwidescience.org/topicpages/h/hot+isostatic+pressure.html	#### Sample records for hot isostatic pressure 1. Effects of Temperature and Pressure of Hot Isostatic Pressing on the Grain Structure of Powder Metallurgy Superalloy. Science.gov (United States) Tan, Liming; He, Guoai; Liu, Feng; Li, Yunping; Jiang, Liang 2018-02-24 The microstructure with homogeneously distributed grains and less prior particle boundary (PPB) precipitates is always desired for powder metallurgy superalloys after hot isostatic pressing (HIPping). In this work, we studied the effects of HIPping parameters, temperature and pressure on the grain structure in PM superalloy FGH96, by means of scanning electron microscope (SEM), electron backscatter diffraction (EBSD), transmission electron microscope (TEM) and Time-of-flight secondary ion spectrometry (ToF-SIMS). It was found that temperature and pressure played different roles in controlling PPB precipitation and grain structure during HIPping, the tendency of grain coarsening under high temperature could be inhibited by increasing HIPping pressure which facilitates the recrystallization. In general, relatively high temperature and pressure of HIPping were preferred to obtain an as-HIPped superalloy FGH96 with diminished PPB precipitation and homogeneously refined grains. 2. Hot isostatic pressing of nanosized WC-Co hardmetals International Nuclear Information System (INIS) Azcona, I.; Ordonez, A.; Sanchez, J.M.; Castro, F.; Dominguez, L. 2001-01-01 A new technique based on hot isostatic pressing (HIP) has been developed to produce dense nanosized WC-Co hardmetals without the addition of grain growth inhibitors. The glass encapsulation process is the key for the effective application of isostatic pressure at temperatures well below those usually required for reaching the closed porosity state in the WC-Co system. Fully dense WC-Co samples with cobalt contents ranging from 10 to 12 wt. % have been obtained by this technique at temperatures between 1000 o C and 1200 o C with 150 MPa of applied isostatic pressure for 30 minutes. The role of isostatic pressure on the activation of densification mechanisms is discussed. (author) 3. Hot isostatic press waste option study report International Nuclear Information System (INIS) Russell, N.E.; Taylor, D.D. 1998-02-01 A Settlement Agreement between the Department of Energy and the State of Idaho mandates that all high-level radioactive waste now stored at the Idaho Chemical Processing Plant be treated so that it is ready to move out of Idaho for disposal by the target date of 2035. This study investigates the immobilization of all Idaho Chemical Processing Plant calcine, including calcined sodium bearing waste, via the process known as hot isostatic press, which produces compact solid waste forms by means of high temperature and pressure (1,050 C and 20,000 psi), as the treatment method for complying with the settlement agreement. The final waste product would be contained in stainless-steel canisters, the same type used at the Savannah River Site for vitrified waste, and stored at the Idaho National Engineering and Environmental Laboratory until a national geological repository becomes available for its disposal. The waste processing period is from 2013 through 2032, and disposal at the High Level Waste repository will probably begin sometime after 2065 4. Hot isostatic press waste option study report Energy Technology Data Exchange (ETDEWEB) Russell, N.E.; Taylor, D.D. 1998-02-01 A Settlement Agreement between the Department of Energy and the State of Idaho mandates that all high-level radioactive waste now stored at the Idaho Chemical Processing Plant be treated so that it is ready to move out of Idaho for disposal by the target date of 2035. This study investigates the immobilization of all Idaho Chemical Processing Plant calcine, including calcined sodium bearing waste, via the process known as hot isostatic press, which produces compact solid waste forms by means of high temperature and pressure (1,050 C and 20,000 psi), as the treatment method for complying with the settlement agreement. The final waste product would be contained in stainless-steel canisters, the same type used at the Savannah River Site for vitrified waste, and stored at the Idaho National Engineering and Environmental Laboratory until a national geological repository becomes available for its disposal. The waste processing period is from 2013 through 2032, and disposal at the High Level Waste repository will probably begin sometime after 2065. 5. Hot Isostatic Press (HIP) vitrification of radwaste concretes International Nuclear Information System (INIS) Siemer, D.D.; Scheetz, B.; Gougar, M.L.D. 1995-01-01 Properly formulated and properly ''canned'' radwaste concretes can be readily hot-isostatically-pressed (HIPed) into materials that exhibit performance equivalent to typical radwaste-type glasses. The HIPing conditions (temperature/pressure) required to turn a concrete waste form into a ''vitrified'' waste form are quite mild and therefore consistent with both safety and high productivity. This paper describes the process and its products with reference to its potential application to Idaho Chemical Processing Plant (ICPP) reprocessing wastes 6. Effect of hot isostatic pressing on reaction-bonded silicon nitride Science.gov (United States) Watson, G. K.; Moore, T. J.; Millard, M. L. 1984-01-01 Specimens of nearly theoretical density have been obtained through the isostatic hot pressing of reaction-bonded silicon nitride under 138 MPa of pressure for two hours at 1850, 1950, and 2050 C. An amorphous phase that is introduced by the hot isostatic pressing partly accounts for the fact that while room temperature flexural strength more than doubles, the 1200 C flexural strength increases significantly only after pressing at 2050 C. 7. Auxiliary equipment and special techniques used for hot isostatic pressing International Nuclear Information System (INIS) Pfeffer, J.B.; Odebo, U. 1977-01-01 The largest use for hot isostatic pressing (HIP) in production is in the consolidation of powder. In principle, powder is filled into a capsule of metal or glass, and the capsule is evacuated, sealed and loaded into the hot isostatic press. Consolidation takes place in the hot isostatic press, at which time the consolidated capsule is removed from the press and the encapsulation material is removed from the consolidated powder body. In both densification and defect healing, HIP is carried out without encapsulating the material. This is possible as the materials that lend themselves to HIP healing initially have a high density without communicating pores; therefore, the material acts as its own capsule. Considerations outside of the hot isostatic press that must be taken into account are examined. Information is included on powder manufacture, fabrication of capsules, powder handling, capsule sealing, and loading and unloading the press 8. Bibliography on Hot Isostatic Pressing (HIP) Technology Science.gov (United States) 1992-11-01 Nimonic API, Rene’ 77 2. MA753, IN-853 7 3. C-103,WC-103 4. Alloy 454, PWA 1480 5. Mar- M250 , Maraging (250) 6. Rene 150, PA 101 (low C) 7. Inconel 718...Pressure Welding Parameters Bryant. W. A. Weld J 54 (12), 433-S-435-S, 1975 ( AD-DI02 316 Key Words: AISI 4340. MAR- M250 . AISI 1020, 9Ni-4Co steel. Inconel...creep rupture. hot corrosion, oxidation, grain size, thermomechanical treatment MAR- M250 1. Microstructures and Mechanical Properties of HIP 9. Hot isostatic-pressing diagrams for fine-particle beryllium powders International Nuclear Information System (INIS) Stoev, P.I.; Papirov, I.I.; Tikhinskij, G.F.; Vasil'ev, A.A. 1995-01-01 Charts of hot isostatic pressing (HIP) for 4 and 8 μm grain beryllium powders are plotted. Values of thickening rates are calculated and their dependences on HIP pressure and temperature are plotted. It is shown, that the relative density powder at growth of HIP pressure and temperature 10. Process and equipment development for hot isostatic pressing treatability study Energy Technology Data Exchange (ETDEWEB) Bateman, Ken; Wahlquist, Dennis; Malewitz, Tim 2015-03-01 Battelle Energy Alliance (BEA), LLC, has developed processes and equipment for a pilot-scale hot isostatic pressing (HIP) treatability study to stabilize and volume reduce radioactive calcine stored at Idaho National Laboratory (INL). In 2009, the U. S. Department of Energy signed a Record of Decision with the state of Idaho selecting HIP technology as the method to treat 5,800 yd^3 (4,400 m^3) of granular zirconia and alumina calcine produced between 1953 and 1992 as a waste byproduct of spent nuclear fuel reprocessing. Since the 1990s, a variety of radioactive and hazardous waste forms have been remotely treated using HIP within INL hot cells. To execute the remote process at INL, waste is loaded into a stainless-steel or aluminum can, which is evacuated, sealed, and placed into a HIP furnace. The HIP simultaneously heats and pressurizes the waste, reducing its volume and increasing its durability. Two 1 gal cans of calcine waste currently stored in a shielded cask were identified as candidate materials for a treatability study involving the HIP process. Equipment and materials for cask-handling and calcine transfer into INL hot cells, as well as remotely operated equipment for waste can opening, particle sizing, material blending, and HIP can loading have been designed and successfully tested. These results demonstrate BEA’s readiness for treatment of INL calcine. 11. High density crystalline boron prepared by hot isostatic pressing in refractory metal containers Science.gov (United States) Hoenig, C.L. 1993-08-31 Boron powder is hot isostatically pressed in a refractory metal container to produce a solid boron monolith with a bulk density at least 2.22 g/cc and up to or greater than 2.34 g/cc. The refractory metal container is formed of tantalum, niobium, tungsten, molybdenum or alloys thereof in the form of a canister or alternatively plasma sprayed or chemical vapor deposited onto a powder compact. Hot isostatic pressing at 1,800 C and 30 PSI (206.8 MPa) argon pressure for four hours produces a bulk density of 2.34 g/cc. Complex shapes can be made. 12. MICROSTRUCTURAL ANALYSIS OF HOT ISOSTATICALLY PRESSED AL-SIC NARCIS (Netherlands) Bronsveld, P.M.; Hosson, J.Th. De; Sargent, M.A.; Alsem, W.H.M. 1991-01-01 The difference between extruded and hot isostatically pressed (HIP) Al6061 both with a T6 final heat treatment and with a 30 wt.% SiC particulate reinforcement is one of densification. The higher density of the HIP material is not translated into a stronger material. The Mg2Si precipitation is 13. Hot isostatic pressing of glass-zeolite composites International Nuclear Information System (INIS) Hash, M.C.; Pereira, C.; Lewis, M.A. 1996-01-01 Glass-zeolite waste forms are being developed for immobilizing the chloride waste salt generated from the electrometallurgical treatment of spent fuel. Glass-zeolite composites with high densities were made using hot isostatic pressing (HIP) techniques. Processing parameters were investigated to yield desirable structural ceramic properties such as mechanical, chemical, and thermal stability. Limits for these parameters were determined by differential thermal and thermogravimetric analysis. The resulting ceramic properties such as bulk density, open or apparent porosity, and leach resistance were determined. In addition, phase equilibria and particle-size distribution were observed by optical light and electron microscopy. Pre-HIP processing techniques were also studied to ensure intimate mixing of the glass and zeolite powders. Particle size distributions resulting from dry blending procedure are appropriate for needed flow and packing characteristics 14. Void formation in ODS EUROFER produced by hot isostatic pressing International Nuclear Information System (INIS) Ortega, Y.; Monge, M.A.; Castro, V. de; Munoz, A.; Leguey, T.; Pareja, R. 2009-01-01 Positron annihilation experiments were performed on oxide dispersion strengthened (ODS) and non-ODS EUROFER prepared by mechanical alloying and hot isostatic pressing. The results revealed the presence of small voids in these materials in the as-HIPed conditions. Their evolution under isochronal annealing experiments was investigated. The coincidence Doppler broadening spectra of ODS EUROFER exhibited a characteristic signature attributed to positron annihilation in Ar-decorated voids at the oxide particle/matrix interfaces. The variation of the positron annihilation parameters with the annealing temperature showed three stages: up to 623 K, between 823 and 1323 K, and above 1323 K. In the temperature range 823-1323 K void coarsening had effect. Above 1323 K some voids annealed out, but others, associated to oxide particles and small precipitates, survived to annealing at 1523 K. Transmission electron microscopy observations were also performed to verify the characteristics of the surviving defects after annealing at 1523 K. 15. Void formation in ODS EUROFER produced by hot isostatic pressing Energy Technology Data Exchange (ETDEWEB) Ortega, Y. [Departamento de Fisica, Universidad Carlos III de Madrid, 28911 Leganes (Spain)], E-mail: [email protected]; Monge, M.A. [Departamento de Fisica, Universidad Carlos III de Madrid, 28911 Leganes (Spain); Castro, V. de [Department of Materials, University of Oxford, Oxford OX1 3PH (United Kingdom); Munoz, A.; Leguey, T.; Pareja, R. [Departamento de Fisica, Universidad Carlos III de Madrid, 28911 Leganes (Spain) 2009-04-30 Positron annihilation experiments were performed on oxide dispersion strengthened (ODS) and non-ODS EUROFER prepared by mechanical alloying and hot isostatic pressing. The results revealed the presence of small voids in these materials in the as-HIPed conditions. Their evolution under isochronal annealing experiments was investigated. The coincidence Doppler broadening spectra of ODS EUROFER exhibited a characteristic signature attributed to positron annihilation in Ar-decorated voids at the oxide particle/matrix interfaces. The variation of the positron annihilation parameters with the annealing temperature showed three stages: up to 623 K, between 823 and 1323 K, and above 1323 K. In the temperature range 823-1323 K void coarsening had effect. Above 1323 K some voids annealed out, but others, associated to oxide particles and small precipitates, survived to annealing at 1523 K. Transmission electron microscopy observations were also performed to verify the characteristics of the surviving defects after annealing at 1523 K. 16. Ductility in hot isostatically pressed 250-grade maraging steel International Nuclear Information System (INIS) German, R.M.; Smugeresky, J.E. 1978-01-01 Prealloyed 250-grade maraging steel powder produced by the rotating electrode process was fully consolidated by hot isostatic pressing (HIP) at 1100 and 1200 0 C. The strength following aging (3 h at 480 0 C) equalled that of wrought material; however, ductility was negligible. This lack of ductility in the powder metallurgy product was traced to titanium segregation which occurred at the powder surface during power production. The formation of a titanium intermetallic at the prior particle boundaries during aging caused failure at low plastic strains. Altered aging treatments successfully broke up the embrittling film and resulted in a significant ductility recovery for the HIP material. Analysis of the fracture process indicates that further ductility gains are possible by reducing the titanium content, refining the particle size, and optimizing the thermal cycles 17. Ductile Fracture Behaviour of Hot Isostatically Pressed Inconel 690 Superalloy Science.gov (United States) Cooper, A. J.; Brayshaw, W. J.; Sherry, A. H. 2018-04-01 Herein we assess the differences in Charpy impact behavior between Hot Isostatically Pressed and forged Inconel 690 alloy over the temperature range of 300 °C to - 196 °C. The impact toughness of forged 690 exhibited a relatively small temperature dependence, with a maximum difference of ca. 40 J measured between 300 °C and - 196 °C, whereas the HIP'd alloy exhibited a difference of approximately double that of the forged alloy over the same temperature range. We have conducted Charpy impact testing, tensile testing, and metallographic analyses on the as-received materials as well as fractography of the failed Charpy specimens in order to understand the mechanisms that cause the observed differences in material fracture properties. The work supports a recent series of studies which assess differences in fundamental fracture behavior between Hot Isostatically Pressed and forged austenitic stainless steel materials of equivalent grades, and the results obtained in this study are compared to those of the previous stainless steel investigations to paint a more general picture of the comparisons between HIP vs forged material fracture behavior. Inconel 690 was selected in this study since previous studies were unable to completely omit the effects of strain-induced martensitic transformation at the tip of the Chary V-notch from the fracture mechanism; Inconel 690 is unable to undergo strain-induced martensitic transformation due to the alloy's high nickel content, thereby providing a sister study with the omission of any martensitic transformation effects on ductile fracture behavior. 18. Densification of boron carbide at relatively low temperatures by hot pressing and hot isostatic pressing International Nuclear Information System (INIS) Telle, R. 1988-01-01 The poor sinterability of B 4 C limits its widespread application because both high temperatures and high pressures are required for a complete densification. Moreover, B 4 C suffers from a low strength and fracture toughness, possesses, however, a high potential because of its extreme hardness. Reaction hot pressing of B 4 C-WC-TiC-Si-Co mixtures resulting in B 4 C-TiB 2 -W 2 B 5 composites of high density exhibit remarkable mechanical properties. The influence of hot isostatic pressing (HIP) on the microstructure and the mechanical properties is investigated in cooperation with participants of the COST 503 activities and related to the strengthening and toughening mechanisms. Difficulties during densification by HIP arise from the evaporation of adsorbed volatiles as well as from the strong swelling of the powder compact due to the sintering reaction. Several HIP cycle designs were tested in order to prevent the bloating of the capsule and to control internal stresses due to the misfit of the thermal expansion of the entire phases. In comparison to single phase B 4 C ceramics, bending strength was improved to 1030 MPa, K Ic to 5.2 MPa/m, while hardness was comparable with HV1=38 GPa. Wear test were performed and related to the toughening mechanisms. (orig.) With 56 refs., 9 tabs., 64 figs 19. The kinetics of dolomite reaction rim growth under isostatic and non-isostatic pressure conditions Science.gov (United States) Helpa, V.; Rybacki, E.; Morales, L. G.; Abart, R.; Dresen, G. H. 2013-12-01 During burial and exhumation, rocks are simultaneously exposed to metamorphic reactions and tectonic stresses. Therefore, the reaction rate of newly formed minerals may depend on chemical and mechanical driving forces. Here, we investigate the reaction kinetics of dolomite (CaMg[CO3]2) rim growth by solid-state reactions experiments on oriented calcite (CaCO3) and magnesite (MgCO3) single crystals under isostatic and non-isostatic pressure conditions. Cylindrical samples of 3-5 mm length and 7 mm diameter were drilled and polished perpendicular to the rhombohedral cleavage planes of natural clear crystals. The tests were performed using a Paterson-type deformation apparatus at P = 400 MPa confining pressure, temperatures, T, between 750 and 850°C, and reaction durations, t, of 2 - 146 h to calculate the kinetic parameters of dolomite rim growth under isostatic stress conditions. For non-isostatic reaction experiments we applied in addition differential stresses, σ, up to 40 MPa perpendicular to the contact interface at T = 750°C for 4 - 171 h duration, initiating minor inelastic deformation of calcite. The thickness of the resulting dolomite reaction rims increases linearly with the square root of time, indicating a diffusion-controlled reaction. The rims consist of two different textural domains. Granular dolomite grains (≈ 2 -5 μm grain size) form next to calcite and elongated palisade-shaped grains (1-6 μm diameter) grow perpendicular to the magnesite interface. Texture measurements with the electron backscatter diffraction technique indicate that the orientations of dolomite grains are mainly influenced by the orientation of the calcite educt crystal, in particular in the granular rim. To some extent, the texture of dolomite palisades is also influenced by the orientation of magnesite. The thickness of the two individual layers increases with temperature. At 400 MPa isostatic pressure, T = 750°C and t = 29 hours, a 5 μm thick granular dolomite layer 20. First wall and shield components manufacturing by hot isostatic pressing International Nuclear Information System (INIS) Lind, Anders; Tegman, R. 1994-01-01 At a meeting in Garching in June 1994 Hot Isostatic Pressing (HIP) was presented as a possible route to manufacture ITER first wall and shield components. The main advantages of the HIP concept include excellent and uniform mechanical properties of the produced materials and joints, high reliability and robustness of the HIP process, double containment of coolant, good flexibility concerning general design as well as size and location for inner cooling tubes, low cost and short delivery times, and a good near net shape capability for components in size up to 15 tons. To assess the applicability of HIP for the manufacturing of ITER first wall and shield components, it was agreed * to choose possible production parameters based in the present know-how, * to produce a compound mock-up in one shot from available solid steel/powder copper/steel tubes to demonstrate the joinability of the materials, * to examine the produced mock-up/materials by multi array ultrasonic testing, limited mechanical testing, metallography, scanning electron microscopy and energy dispersive spectroscopy, and * to compile data on Type 316L steels produced by HIP. Preliminary results and the mock-up were presented at a meeting in Garching in mid July 1994. This study clearly shows the excellent joinability of a copper alloy (Cu-0.5%Zr) and stainless steels (Type 304, 316 L) by HIP at temperatures close to the melting temperature of copper, with only limited influence on the microstructures, which makes it possible to HIP the first wall and shield structure in one step. Excellent mechanical properties of the compound are obtained with the copper alloy and not the joint being the weakest part. 7 refs, 21 figs, 1 tab 1. Benefits of Hot Isostatic Pressure/Powdered Metal (HIP/PM) and Additive Manufacturing (AM) To Fabricate Advanced Energy System Components Energy Technology Data Exchange (ETDEWEB) Horton, Nancy [Energy Industries of Ohio, Cleveland, OH (United States); Sheppard, Roy [Energy Industries of Ohio, Cleveland, OH (United States) 2016-12-31 Advanced Energy systems require large, complex components produced from materials capable of withstanding severe operating environments (high temperature, pressure, corrosivity). Such parts can be difficult to source, as conventional material processing technologies must be tailored to ensure a safe and cost effective approach to large-scale manufacture of quality structural advanced alloy components that meet the performance specifications of AE systems. (HIP/PM) has shown advantages over other manufacturing methods when working with these materials. For example, using HIP’ing in lieu of casting means significant savings in raw material costs, which for expensive, high-nickel alloys can be considerable for large-scale production. Use of HIP/PM also eliminates the difficulties resulting from reactivity of these materials in the molten state and facilitates manufacture of the large size requirements of the AE industry, producing a part that is defect and porosity free, thus further reducing or eliminating time and expense of post processing machining and weld repair. New advances in Additive Manufacturing (AM) techniques make it possible to further expand the benefits of HIP/PM in producing AE system components to create an even more robust manufacturing approach. Traditional techniques of welding and forming sheet metal to produce the HIP canisters can be time consuming and costly, with limitations on the complexity of part which can be achieved. A key benefit of AM is the freedom of design that it offers, so use of AM could overcome such challenges, ultimately enabling redesign of complete energy systems. A critical step toward this goal is material characterization of the required advanced alloys, for use in AM. Using Haynes 282, a high nickel alloy of interest to the Fossil Energy community, particularly for Advanced-UltraSuperCritical (AUSC) operating environments, as well as the crosscutting interests of the aerospace, defense and medical markets, this 2. Void formation in ODS EUROFER produced by hot isostatic pressing Energy Technology Data Exchange (ETDEWEB) Ortega, Y.; Monge, M.A.; Munoz, A.; Leguey, T.; Pareja, R. [Madrid Univ. Carlos-3, Dept. de Fisica (Spain); Castro, V. de [Oxford Univ., Dept. of Materials (United Kingdom) 2007-07-01 Full text of publication follows: An obstacle in the development of oxide dispersion strengthened (ODS) steels for structural applications in fusion reactors is the toughness lack of the material produced by powder metallurgy and consolidated by hot isostatic pressing (HIP). In particular, ODS EUROFER steel with Y{sub 2}O{sub 3} particles appears to exhibit poor impact properties. To asses the capabilities of this material, it is necessary elucidate if its failure is an inherent characteristic of the production process that can not be mitigated by normalizing and tempering treatments. In order to investigate this particular point, the evolution of the structural defects retained in the ODS material during isochronal annealing has been probed by positron annihilation spectroscopy. The present study has been performed on bail milled EUROFER powders consolidated by HIP, containing 0.25 wt % Y{sub 2}O{sub 3} and without Y{sub 2}O{sub 3}. For comparison, un-milled EUROFER powder consolidated under identical conditions, and as-received EUROFER97 plate produced by Boehler AG have been also investigated. Samples from these four materials were isochronally annealed for 90 min up to 1323 K. Materials produced from milled powders had a longer positron lifetime than the one produced from un-milled powder or the EUROFER plate. In the material containing Y{sub 2}O{sub 3}, i.e. in ODS EUROFER, annealing above 723 K produced a continuous increase in the mean positron lifetime <{tau}> up to reach a maximum value of 208 ps after annealing at 1223 K. A similar annealing behavior was observed for Y{sub 2}O{sub 3}-free milled EUROFER (milled EUROFER), but the <{tau}> value steeply changed from {approx}160 ps at 823 K to {approx}200 ps after annealing at 1023 K. Subsequent anneals above this temperature produced meaningless changes in <{tau}>. The <{tau}> increase in milled EUROFER was accompanied by the intensity increase of a lifetime component of {approx}360 ps that is characteristic 3. Effect of hot isostatic pressing on the properties of sintered alpha silicon carbide Science.gov (United States) Watson, G. K.; Moore, T. J.; Millard, M. L. 1985-01-01 Two lots of alpha silicon carbide were isostatically hot-pressed under 138 MPa for 2 h in Ar at temperatures up to 2200 C. Nearly theoretically dense specimens resulted. Hot isostatic pressing increased both room-temperature strength and 1200 C strength, and resulted in improved reliability. One lot of material which was pressed at 2200 C showed increases of about 20 percent in room-temperature strength and about 50 percent in 1200 C flexural strength; the Weibull modulus improved about 100 percent. 4. Defect structures in MgB2 wires introduced by hot isostatic pressing International Nuclear Information System (INIS) Liao, X Z; Serquis, A; Zhu, Y T; Civale, L; Hammon, D L; Peterson, D E; Mueller, F M; Nesterenko, V F; Gu, Y 2003-01-01 The microstructures of MgB 2 wires prepared by the powder-in-tube technique and subsequent hot isostatic pressing were investigated using transmission electron microscopy. A large amount of crystalline defects including small-angle twisting, tilting and bending boundaries, in which high densities of dislocations reside, was found forming sub-grains within MgB 2 grains. It is believed that these defects resulted from particle deformation during the hot isostatic pressing process and are effective flux pinning centres that contribute to the high critical current densities of the wires at high temperatures and at high fields 5. Development of Be/Glidcop joint obtained by hot isostatic pressing diffusion bonding for high in-service temperature Energy Technology Data Exchange (ETDEWEB) Saint-Antonin, F.; Bucci, P.; Burlet, H.; Le Marois, G. [CEA Centre dEtudes de Grenoble, 38 (France); Barberi, D.; Laille, A. 1998-01-01 This paper addresses some aspects of the beryllium-Glidcop joining by Hot Isostatic Pressing diffusion Bonding. The quality of a joint is mainly dependent on the interface microstructure. Thus, as Be/copper direct bonding is not recommended, the choice of interlayers is a critical point. The joining process parameters, i.e. temperature, pressure and time, must take into account the in-service requirements, the mechanical and metallurgical properties of each material. The Be/Glidcop joining process developed at CEA/Grenoble is presented here. (author) 6. Expanded Analysis of Hot Isostatic Pressed Iodine-Loaded Silver-Exchanged Mordenite Energy Technology Data Exchange (ETDEWEB) Jubin, R. T. [ORNL; Bruffey, S. H. [ORNL; Patton, K. K. [ORNL 2014-09-30 Reduced silver-exchanged mordenite (Ag0Z) is being evaluated as a potential material to control the release of radioactive iodine that is released during the reprocessing of used nuclear fuel into the plant off-gas streams. The purpose of this study was to determine if hot pressing could directly convert this iodine loaded sorbent into a waste form suitable for long-term disposition. The minimal pretreatment required for production of pressed pellets makes hot pressing a technically and economically desirable process. Initial scoping studies utilized hot uniaxial pressing (HUPing) to prepare samples of non-iodine-loaded reduced silver exchanged mordenite (Ag0Z). The resulting samples were very fragile due to the low pressure (~ 28 MPa) used. It was recommended that hot isostatic pressing (HIPing), performed at higher temperatures and pressures, be investigated. HIPing was carried out in two phases, with a third and final phase currently underway. Phase I evaluated the effects of pressure and temperature conditions on the manufacture of a pressed sample. The base material was an engineered form of silver zeolite. Six samples of Ag0Z and two samples of I-Ag0Z were pressed. It was found that HIPing produced a pressed pellet of high density. Analysis of each pressed pellet by scanning electron microscopy-energy dispersive spectrophotometry (SEM-EDS) and X-ray diffraction (XRD) demonstrated that under the conditions used for pressing, the majority of the material transforms into an amorphous structure. The only crystalline phase observed in the pressed Ag0Z material was SiO2. For the samples loaded with iodine (I-Ag0Z) iodine was present as AgI clusters at low temperatures, and transformed into AgIO4 at high temperatures. Surface mapping and EDS demonstrate segregation between silver iodide phases and silicon dioxide phases. Based on the results of the Phase I study, an expanded test matrix was developed to examine the effects of multiple source materials, compositional 7. Atlas of hot isostatic beryllium powder pressing diagrams International Nuclear Information System (INIS) Stoev, P.I.; Papirov, I.I.; Tikhinskij, G.F.; Vasil'ev, A.A. 1995-01-01 Diagrams of hot isotopic pressing (HIP) of beryllium powder with different grain size in a wide range of pressing parameters are built by mathematical modeling methods. The HIP diagrams presented are divided into 3 groups: parametric dependencies D=f(P,T); technological HIP diagrams; compacting mechanisms. The created data bank permits to optimise beryllium powder HIP with changing parameters. 4 refs., 23 figs 8. Age hardening in rapidly solidified and hot isostatically pressed beryllium-aluminum-silver alloys International Nuclear Information System (INIS) Carter, D.H.; McGeorge, A.C.; Jacobson, L.A.; Stanek, P.W. 1995-01-01 Three different alloys of beryllium, aluminum and silver were processed to powder by centrifugal atomization in a helium atmosphere. Alloy compositions were, by weight, 50% Be, 47.5% Al, 2.5% Ag, 50% Be, 47% Al, 3% Ag, and 50% Be, 46% Al, 4% Ag. Due to the low solubility of both aluminum and silver in beryllium, the silver was concentrated in the aluminum phase, which appeared to separate from the beryllium in the liquid phase. A fine, continuous composite beryllium-aluminum microstructure was formed, which did not significantly change after hot isostatically pressing at 550 C for one hour at 30,000 psi argon pressure. Samples of HIP material were solution treated at 550 C for one hour, followed by a water quench. Aging temperatures were 150, 175, 200 and 225 C for times ranging from one half hour to 65 hours. Hardness measurements were made using a diamond pyramid indenter with a load of 1 kg. Results indicate that peak hardness was reached in 36--40 hours at 175 C and 12--16 hours at 200 C aging temperature, relatively independent of alloy composition 9. Encapsulation of krypton-85 in zeolite molecular sieve with a hot isostatic press International Nuclear Information System (INIS) Christensen, A.B.; DelDebbio, J.A.; Knecht, D.A.; Tanner, J.E. 1986-01-01 This paper describes pilot and full-scale experiments which demonstrated the feasibility of immobilizing Kr-85 in a zeolite 5A/glass mixture and compacting it before disposal. The full volume of a one-liter hot isostatic press (HIP) was used to trap argon in zeolite 5A. For radioactive krypton the HIP was modified to isolate the Kr-85 in the work zone. Details of the HIP modifications, experimental procedure, and sample analysis are reported 10. Behaviour and damage of a superalloy prepared by hot isostatic compression International Nuclear Information System (INIS) Dubiez-Le-Goff, Sophie 2003-01-01 This work deals with the behavior and damage of Udimet 720 superalloy prepared by hot isostatic compression. This alloy is considered for manufacturing turbine disks of high temperature reactors (HTR). The material choice for HTR turbine disk depends on the following criteria: a good creep resistance until 700 C, a good behaviour under an helium impure atmosphere, a possible implementation under a disk of 1.5 m diameter. (author) [fr 11. Consolidation of W–Ta composites: Hot isostatic pressing and spark and pulse plasma sintering Energy Technology Data Exchange (ETDEWEB) Dias, M., E-mail: [email protected] [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Guerreiro, F. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Correia, J.B. [LNEG, Laboratório Nacional de Energia e Geologia, Estrada do Paço do Lumiar, 1649-038 Lisboa (Portugal); Galatanu, A. [National Institute of Materials Physics, Atomistilor 105 bis Bucharest-Magurele, 077125 Ilfov (Romania); Rosiński, M. [Warsaw University of Technology, Faculty of Materials Science and Engineering, Warsaw (Poland); Monge, M.A.; Munoz, A. [Departamento de Física, Univerdidad Carlos III de Madrid, Avd. de la Universidad 30, 28911 Madrid (Spain); Alves, E. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Carvalho, P.A. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); CeFEMA, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal) 2015-10-15 Highlights: • Consolidation of W–Ta composites using three techniques: HIP, SPS and PPS. • Comparison of consolidation methods in terms of W–Ta interdiffusion and densification. • Microstructure analysis in terms of oxides formation. - Abstract: Composites consisting of tantalum fiber/powder dispersed in a nanostructured W matrix have been consolidated by spark and pulse plasma sintering as well as by hot isostatic pressing. The microstructural observations revealed that the tungsten–tantalum fiber composites consolidated by hot isostatic pressing and pulse plasma sintering presented a continuous layer of Ta{sub 2}O{sub 5} phase at the W/Ta interfaces, while the samples consolidated by spark plasma sintering evidenced a Ta + Ta{sub 2}O{sub 5} eutectic mixture due to the higher temperature of this consolidation process. Similar results have been obtained for the tungsten–tantalum powder composites. A (W, Ta) solid solution was detected around the prior nanostructured W particles in tungsten–tantalum powder composites consolidated by spark and pulse plasma sintering. Higher densifications were obtained for composites consolidated by hot isostatic pressing and pulse plasma sintering. 12. Forming and control of pores by capsule-free hot isostatic pressing in NiTi shape memory alloys International Nuclear Information System (INIS) Yuan, B; Zhu, M; Gao, Y; Li, X; Chung, C Y 2008-01-01 In this study, the pore evolution process of porous NiTi shape memory alloys (SMAs) fabricated by capsule-free hot isostatic pressing (CF-HIP) was investigated by adopting different fabricating parameters. It is shown that porous NiTi SMAs with homogeneous pore distribution and nearly spherical pore shape can be prepared by CF-HIP under suitable conditions. In addition, two novel pore structures were produced, one with a sandwich-like structure, and another with controlled gradient of porosity along the radial direction, with pore size increasing from the outside towards the center of the specimen. The former was obtained by balancing the pressure in the HIP chamber and the gas pressure resulting from the gas expansion in the green sample. The latter resulted from the formation of air bubbles in the liquid phase during the sintering 13. Hot Isostatic Pressing of Engineered Forms of I-AgZ Energy Technology Data Exchange (ETDEWEB) Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Watkins, Thomas R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jordan, Jacob A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Parks, Mackenzie L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States) 2017-11-01 Hot isostatic pressing (HIP) is being considered for direct conversion of 129I-bearing materials to a radiological waste form. The removal of volatile radioactive 129I from the off-gas of a nuclear fuel reprocessing facility will be necessary to comply with regulatory requirements regarding reprocessing facilities sited within the United States, and any iodine-containing media or solid sorbents generated by offgas abatement will require disposal. Zeolite minerals such as silver-exchanged mordenite (AgZ) have been studied as potential iodine sorbents and will contain 129I as chemisorbed AgI. Oak Ridge National Laboratory (ORNL) has conducted several recent studies on the HIP of both iodine-loaded AgZ (I-AgZ) and other iodine-bearing zeolite minerals. The goal of these research efforts is to achieve a stable, highly leach resistant material that is reduced in volume as compared to bulk iodine-loaded I-AgZ. Through the use of HIP, it may be possible to achieve this with the addition of little or no additional materials (waste formers). Other goals for the process include that the waste form will be tolerant to high temperatures and pressures, not chemically hazardous, and that the process will result in minimal secondary waste generation. This document describes the preparation of 27 samples that are distinct from previous efforts in that they are prepared exclusively with an engineered form of AgZ that is manufactured using a binder. Iodine was incorporated solely by chemisorption. This base material is expected to be more representative of an operational system than were samples prepared previously with pure minerals. 14. Preliminary Study on Hot Isostatic Pressing Diffusion Bonding for CLAM Steel International Nuclear Information System (INIS) Chunjing Li; Qunying Huang; Yican Wu 2006-01-01 China Low Activation Martensitic (CLAM) steel is being developed in ASIPP (Institute of Plasma Physics, Chinese Academy of Sciences) since three years ago. CLAM is selected as the major candidate structure materials for the FDS series design of fusion reactors and for China liquid metal LiPb Test Blanket Module (TBM) for ITER i.e. DFLL-TBM, which are being carried out in ASIPP. Since the hot isostatic pressing (HIP) bonding technique is one of the main candidate bonding techniques for manufacturing of the first wall of a fusion reactor, research of the HIP technique on CLAM/CLAM is greatly needed. Preliminary HIP diffusion bonding experiments on CLAM steel have been performed. A few machining approaches such as dry-milling, turnery and grounding etc. were used to prepare the sample surfaces and then they were degreased with a mixture of alcohol, ether and acetone in an ultrasonic bath. The samples were joined by HIP diffusion bonding with the compression pressure of 150 MPa and the holding time of 2 ∼ 3 hours under different temperatures between 950 deg. and 1100 deg.. Different seal techniques of the capsules were studied as well. Then appropriate post heat treatment was done. Tests on mechanical properties of the joints such as tensile strength and impact toughness have been performed. The preliminary results show that the tensile properties are roughly the same as those of the base material. The absorbed energy of the joints at present is a little low and further research is needed to increase it. Microstructure of the joints was studied by optical microscope, SEM and TEM. Compositions of the defects on the joining line were analyzed by EDS. Through analysis of the results, optimized parameters for HIP are given. (author) 15. Flux pinning in hot isostatically pressed Bi2Sr2CaCu2Ox International Nuclear Information System (INIS) Miller, D.J.; Sengupta, S.; Hettinger, J.D.; Shi, D.; Gray, K.E.; Nash, A.S.; Goretta, K.C. 1992-01-01 Magnetic hysteresis data were taken from 4.2 to 35 K on Bi 2 Sr 2 CaCu 2 O x samples that were hot isostatically pressed at 105 MPa in an inert atmosphere at 825 degree C. One set of samples was pressed for only 15 min while the other was pressed for 120 min. The samples pressed for 15 min contained a high density of dislocations and planar faults, while the samples pressed for 120 min contained fewer dislocations and faults, with most dislocations present within subgrain boundaries. The samples with the complex dislocation/planar fault structures exhibited substantially larger hysteresis loops, suggesting enhanced flux pinning 16. Effect of Temperature on the Fracture Toughness of Hot Isostatically Pressed 304L Stainless Steel Science.gov (United States) Cooper, A. J.; Brayshaw, W. J.; Sherry, A. H. 2018-03-01 Herein, we have performed J- Resistance multi-specimen fracture toughness testing of hot isostatically pressed (HIP'd) and forged 304L austenitic stainless steel, tested at elevated (300 °C) and cryogenic (- 140 °C) temperatures. The work highlights that although both materials fail in a pure ductile fashion, stainless steel manufactured by HIP displays a marked reduction in fracture toughness, defined using J 0.2BL, when compared to equivalently graded forged 304L, which is relatively constant across the tested temperature range. 17. Effect of Temperature on the Fracture Toughness of Hot Isostatically Pressed 304L Stainless Steel OpenAIRE Cooper, Adam J.; Sherry, Andrew 2018-01-01 Herein, we have performed J-Resistance multi-specimen fracture toughness testing of hot isostatically pressed (HIP’d) and forged 304L austenitic stainless steel, tested at elevated (300 °C) and cryogenic (− 140 °C) temperatures. The work highlights that although both materials fail in a pure ductile fashion, stainless steel manufactured by HIP displays a marked reduction in fracture toughness, defined using J0.2BL, when compared to equivalently graded forged 304L, which is relatively constant... 18. Experimental and Simulation Analysis of Hot Isostatic Pressing of Gas Atomized Stainless Steel 316L Powder Compacts International Nuclear Information System (INIS) Lin, Dongguo; Park, Seong Jin; Ha, Sangyul; Shin, Youngho; Park, Dong Yong; Chung, Sung Taek; Bollina, Ravi; See, Seongkyu 2016-01-01 In this work, both experimental and numerical studies were conducted to investigate the densification behavior of stainless steel 316L (STS 316L) powders during hot isostatic pressing (HIP), and to characterize the mechanical properties of HIPed specimens. The HIP experiments were conducted with gas atomized STS 316L powders with spherical particle shapes under controlled pressure and temperature conditions. The mechanical properties of HIPed samples were determined based on a series of tensile tests, and the results were compared to a reference STS 316L sample prepared by the conventional process, i.e., extrusion and annealing process. Corresponding microstructures before and after tensile tests were observed using scanning electron microscopy and their relationships to the mechanical properties were addressed. Furthermore, a finite element simulation based on the power-law creep model was carried out to predict the density distribution and overall shape change of the STS316L powder compact during HIP process, which agreed well with the experimental results. 19. Experimental and Simulation Analysis of Hot Isostatic Pressing of Gas Atomized Stainless Steel 316L Powder Compacts Energy Technology Data Exchange (ETDEWEB) Lin, Dongguo; Park, Seong Jin [Pohang University of Science and Technology, Pohang (Korea, Republic of); Ha, Sangyul [Samsung Electro-Mechanics, Suwon (Korea, Republic of); Shin, Youngho [Doosan Heavy Industries and Construction Co., Ltd., Changwon (Korea, Republic of); Park, Dong Yong [Korea Institute of Energy Research, Daejeon (Korea, Republic of); Chung, Sung Taek [CetaTech Inc., Sacheon (Korea, Republic of); Bollina, Ravi [Bahadurpally Jeedimetla, Hyderabad (India); See, Seongkyu [POSCO, Pohang (Korea, Republic of) 2016-10-15 In this work, both experimental and numerical studies were conducted to investigate the densification behavior of stainless steel 316L (STS 316L) powders during hot isostatic pressing (HIP), and to characterize the mechanical properties of HIPed specimens. The HIP experiments were conducted with gas atomized STS 316L powders with spherical particle shapes under controlled pressure and temperature conditions. The mechanical properties of HIPed samples were determined based on a series of tensile tests, and the results were compared to a reference STS 316L sample prepared by the conventional process, i.e., extrusion and annealing process. Corresponding microstructures before and after tensile tests were observed using scanning electron microscopy and their relationships to the mechanical properties were addressed. Furthermore, a finite element simulation based on the power-law creep model was carried out to predict the density distribution and overall shape change of the STS316L powder compact during HIP process, which agreed well with the experimental results. 20. FeCrAl and Zr alloys joined using hot isostatic pressing for fusion energy applications International Nuclear Information System (INIS) Park, Dong Jun; Kim, Hyun Gil; Park, Jeong Yong; Jung, Yang Il; Park, Jung Hwan; Koo, Yang Hyun 2016-01-01 Highlights: • FeCrAl and Zr alloys were successfully joined by hot isostatic pressing (HIP). • The thickness of diffusion layer increased with an increase in HIP temperature. • Significant inter-diffusion was observed for HIP at 1150 °C. • Maximum joint strength was achieved at HIP temperature of 700 °C. - Abstract: FeCrAl and Zr alloys were joined by a hot isostatic pressing (HIP) method for fusion energy applications. The optimum conditions for the joining process were studied. The HIP temperatures were varied from 700 to 1050 °C. The mechanical properties of the HIPed samples were evaluated by four-point bending and tensile tests. The FeCrAl and Zr alloys HIPed at 700 °C showed higher joint strength than the other samples. The joint strength decreased with an increase in the HIP temperature from 700 to 950 °C and significantly dropped at 1050 °C. Transmission electron microscopy, scanning electron microscopy, and optical microscopy were used to characterize the joints and interface region of the HIPed samples. The joints appeared to be tightly bonded and no intermetallic compounds or gaps were observed at the interface for HIP temperatures up to 950 °C. A diffusion layer formed at the interface and its thickness increased with the HIP temperature. HIP at 1050 °C, on the other hand, resulted in significant inter-diffusion and formation of brittle inter-metallic compounds at the interface. 1. Processing and properties of calcium phosphates bioceramics by hot isostatic pressing Directory of Open Access Journals (Sweden) Boilet Laurent 2013-11-01 Full Text Available Stoichiometric β-tricalcium phosphate (β-TCP, hydroxyapatite (HA and biphasic calcium phosphate (TCP/HA 60/40 %wt, BCP40 powders were synthesized by chemical precipitation of aqueous solutions of diammonium phosphate and calcium nitrate. After a calcination treatment and a milling step, powders were shaped by slip-casting. The sintering temperature effect on the density and the average grain size was investigated. By natural sintering, densities between 98 and 99.8% were obtained. Hot Isostatic Pressing (HIP treatment was carried out after a pre-sintering of these materials. Transparent or translucent samples were obtained, indicating a relative density very close to the theoretical value (>99.9%. Mechanical properties (three-point bending strength, fracture toughness, Young's modulus and Vickers hardness were measured on hipped materials with similar grain size (∼0.7μm. 2. Characterization of 316L(N)-IG SS joint produced by hot isostatic pressing technique International Nuclear Information System (INIS) Nakano, J.; Miwa, Y.; Tsukada, T.; Kikuchi, M.; Kita, S.; Nemoto, Y.; Tsuji, H.; Jitsukawa, S. 2002-01-01 Type 316L(N) stainless steel of the international thermonuclear experimental reactor grade (316L(N)-IG SS) is being considered for the first wall/blanket module. Hot isostatic pressing (HIP) technique is expected for the fabrication of the module. To evaluate the integrity and susceptibility to stress corrosion cracking (SCC) of HIPed 316L(N)-IG SS, tensile tests in vacuum and slow strain rate tests in high temperature water were performed. Specimen with the HIPed joint had similar tensile properties to specimens of 316L(N)-IG SS, and did not show susceptibility to SCC in oxygenated water at 423 K. Thermally sensitized specimen was low susceptible to SCC even in the creviced condition. It is concluded that the tensile properties of HIPed SS are as high as those of the base alloy and the HIP process caused no deleterious effects 3. Room temperature deformation mechanisms in ultrafine-grained materials processed by hot isostatic pressing International Nuclear Information System (INIS) Cao, W.Q.; Dirras, G.F.; Benyoucef, M.; Bacroix, B. 2007-01-01 Ultrafine-grained (uf-g) and microcrystalline-grained (mc-g) irons have been fabricated by hot isostatic pressing of nanopowders. The mechanical properties have been characterized by compressive tests at room temperature and the resulting microstructures and textures have been determined by combining electron back scatter diffraction and transmission electron microscopy. A transition of the deformation mode, from work hardening to work softening occurs for grain sizes below ∼1 μm, reflecting a transition of the deformation mode from homogeneous to localized deformation into shear bands (SBs). The homogeneous deformation is found to be lattice dislocation-based while the deformation within SBs involves lattice dislocations as well as boundary-related mechanisms, possibly grain boundary sliding accommodated by boundary opening 4. Yb:Y2O3 transparent ceramics processed with hot isostatic pressing Science.gov (United States) Wang, Jun; Ma, Jie; Zhang, Jian; Liu, Peng; Luo, Dewei; Yin, Danlei; Tang, Dingyuan; Kong, Ling Bing 2017-09-01 Highly transparent 5 at.% Yb:Y2O3 ceramics were fabricated by using a combination method of vacuum sintering and hot isostatic pressing (HIP). Co-precipitated Yb:Y2O3 powders, with 1 at.% ZrO2 as the sintering aid, were used as the starting material. The Yb:Y2O3 ceramics, vacuum sintered at 1700 °C for 2 h and HIPed at 1775 °C for 4 h, exhibited small grain size of 1.9 μm and highly dense microstructure. In-line optical transmittance of the ceramics reached 83.4% and 78.9% at 2000 and 600 nm, respectively. As the ceramic slab was pumped by a fiber-coupled laser diode at about 940 nm, a maximum output power of 0.77 W at 1076 nm was achieved, with a corresponding slope efficiency of 10.6%. 5. Tensile and fracture characteristics of oxide dispersion strengthened Fe–12Cr produced by hot isostatic pressing Energy Technology Data Exchange (ETDEWEB) Castro, Vanessa de, E-mail: [email protected] [Departamento de Física, Universidad Carlos III de Madrid, Avda. de la Universidad 30, 28911 Leganés, Madrid (Spain); Garces-Usan, Jose Maria; Leguey, Teresa; Pareja, Ramiro [Departamento de Física, Universidad Carlos III de Madrid, Avda. de la Universidad 30, 28911 Leganés, Madrid (Spain) 2013-11-15 The mechanical characteristics of a model oxide dispersion strengthened (ODS) alloy with nominal composition Fe–12 wt%Cr–0.4 wt%Y{sub 2}O{sub 3} were investigated by means of microhardness measurements, tensile tests up to fracture in the temperature range of 298–973 K, and fracture surface analyses. A non-ODS Fe–12 wt%Cr alloy was also studied to assess the real capacity of the oxide dispersion for strengthening the alloy. The materials were produced by mechanical alloying followed by hot isostatic pressing consolidation and heat treatment at 1023 K. The strengthening effect of the oxide nanodispersion was effective at all temperatures studied, although the tensile strength converges towards the one obtained for the reference alloy at higher temperatures. Moreover, the ODS alloys failed prematurely at T < 673 K due to the presence of Y-rich inclusions, as seen in the fracture surface of these alloys. 6. Development of oxide dispersion strengthened W alloys produced by hot isostatic pressing International Nuclear Information System (INIS) Martinez, J.; Savoini, B.; Monge, M.A.; Munoz, A.; Pareja, R. 2011-01-01 A powder metallurgy technique has been developed to produce oxide strengthened W-Ti and W-V alloys using elemental powders and nanosized powders of La 2 O 3 or Y 2 O 3 as starting materials. The alloys consolidated by hot isostatic pressing resulted in high-density materials having an ultrafine-grained structure and microhardness values in the range 7-13 GPa. Atom force microscopy studies show a topographic relief in the Ti and V pools that appear in the consolidated alloys. This relief is attributed to the heterogeneous nucleation of martensite plates. The preliminary transmission electron microscopy studies have revealed that a dispersion of nanoparticles can be induced in these alloys produced via the present technique. 7. Development of oxide dispersion strengthened W alloys produced by hot isostatic pressing Energy Technology Data Exchange (ETDEWEB) Martinez, J.; Savoini, B.; Monge, M.A. [Departamento de Fisica, Universidad Carlos III de Madrid, 28911 Leganes (Spain); Munoz, A., E-mail: [email protected] [Departamento de Fisica, Universidad Carlos III de Madrid, 28911 Leganes (Spain); Pareja, R. [Departamento de Fisica, Universidad Carlos III de Madrid, 28911 Leganes (Spain) 2011-10-15 A powder metallurgy technique has been developed to produce oxide strengthened W-Ti and W-V alloys using elemental powders and nanosized powders of La{sub 2}O{sub 3} or Y{sub 2}O{sub 3} as starting materials. The alloys consolidated by hot isostatic pressing resulted in high-density materials having an ultrafine-grained structure and microhardness values in the range 7-13 GPa. Atom force microscopy studies show a topographic relief in the Ti and V pools that appear in the consolidated alloys. This relief is attributed to the heterogeneous nucleation of martensite plates. The preliminary transmission electron microscopy studies have revealed that a dispersion of nanoparticles can be induced in these alloys produced via the present technique. 8. Tensile and fracture characteristics of oxide dispersion strengthened Fe–12Cr produced by hot isostatic pressing International Nuclear Information System (INIS) Castro, Vanessa de; Garces-Usan, Jose Maria; Leguey, Teresa; Pareja, Ramiro 2013-01-01 The mechanical characteristics of a model oxide dispersion strengthened (ODS) alloy with nominal composition Fe–12 wt%Cr–0.4 wt%Y 2 O 3 were investigated by means of microhardness measurements, tensile tests up to fracture in the temperature range of 298–973 K, and fracture surface analyses. A non-ODS Fe–12 wt%Cr alloy was also studied to assess the real capacity of the oxide dispersion for strengthening the alloy. The materials were produced by mechanical alloying followed by hot isostatic pressing consolidation and heat treatment at 1023 K. The strengthening effect of the oxide nanodispersion was effective at all temperatures studied, although the tensile strength converges towards the one obtained for the reference alloy at higher temperatures. Moreover, the ODS alloys failed prematurely at T < 673 K due to the presence of Y-rich inclusions, as seen in the fracture surface of these alloys 9. Transformation of Cs-IONSIV® into a ceramic wasteform by hot isostatic pressing Science.gov (United States) Chen, Tzu-Yu; Maddrell, Ewan R.; Hyatt, Neil C.; Gandy, Amy S.; Stennett, Martin C.; Hriljac, Joseph A. 2018-01-01 A simple method to directly convert Cs-exchanged IONSIV® IE-911 into a ceramic wasteform by hot isostatic pressing (1100 °C/190 MPa/2 hr) is presented. Two major Cs-containing phases, Cs2TiNb6O18 and Cs2ZrSi6O15, and a series of mixed oxides form. The microstructure and phase assemblage of the samples as a function of Cs content were examined using XRD, XRF, SEM and TEM/EDX. The chemical aqueous durability of the materials was investigated using the MCC-1 and PCT-B standard test methods. For HIPed Cs-IONSIV® samples, the MCC-1 normalised release rates of Cs were low rates are indicative of a safe long-term immobilisation matrix for Cs formed directly from spent IONSIV®. It was also demonstrated that the phase formation can be altered by adding Ti metal due to a controlled redox environment. 10. M3FT-17OR0301070211 - Preparation of Hot Isostatically Pressed AgZ Waste Form Samples Energy Technology Data Exchange (ETDEWEB) Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jordan, Jacob A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States) 2017-10-01 The production of radioactive iodine-bearing waste forms that exhibit long-term stability and are suitable for permanent geologic disposal has been the subject of substantial research interest. One potential method of iodine waste form production is hot isostatic pressing (HIP). Recent studies at Oak Ridge National Laboratory (ORNL) have investigated the conversion of iodine-loaded silver mordenite (I-AgZ) directly to a waste form by HIP. ORNL has performed HIP with a variety of sample compositions and pressing conditions. The base mineral has varied among AgZ (in pure and engineered forms), silver-exchanged faujasite, and silverexchanged zeolite A. Two iodine loading methods, occlusion and chemisorption, have been explored. Additionally, the effects of variations in temperature and pressure of the process have been examined, with temperature ranges of 525°C–1,100°C and pressure ranges of 100–300 MPa. All of these samples remain available to collaborators upon request. The sample preparation detailed in this document is an extension of that work. In addition to previously prepared samples, this report documents the preparation of additional samples to support stability testing. These samples include chemisorbed I-AgZ and pure AgI. Following sample preparation, each sample was processed by HIP by American Isostatic Presses Inc. and returned to ORNL for storage. ORNL will store the samples until they are requested by collaborators for durability testing. The sample set reported here will support waste form durability testing across the national laboratories and will provide insight into the effects of varied iodine content on iodine retention by the produced waste form and on potential improvements in waste form durability provided by the zeolite matrix. 11. Strength-toughness relations in sintered and isostatically hot-pressed ZrO2-toughened Al2O3 International Nuclear Information System (INIS) Hori, S.; Yoshimura, M.; Somiya, S. 1986-01-01 The fracture toughness of fine-grained undoped ZrO 2 -toughened Al 2 O 3 (ZTA) was essentially unchanged by post-sintering hot isostatic pressing and increased monotonically with ZrO 2 additions up to 25 wt%. The strength of ZTA with 5 to 15 wt% tetragonal ZrO 2 , which depended monotonically on the amount of ZrO 2 present before hot isostatic pressing, was increased by pressing but became almost constant between 5 and 15 wt% ZrO 2 addition. The strength appeared to be controlled by pores before pressing and by surface flaws after pressing; the size of flaws after pressing increased with ZrO 2 content. The strength of ZTA containing mostly monoclinic ZrO 2 (20 to 25 wt%) remained almost constant despite the noticeable density increase upon hot isostatic pressing because the strength was controlled by preexisting microcracks whose extent did not change on postsintering pressing. These strength-toughness relations in sintered and isostatically hot-pressed ZTA are explained on the basis of R-curve behavior. The importance of the contribution of microcracks to the toughness of ZTA is emphasized 12. Tensile Fracture Behavior of 316L Austenitic Stainless Steel Manufactured by Hot Isostatic Pressing Science.gov (United States) Cooper, A. J.; Brayshaw, W. J.; Sherry, A. H. 2018-02-01 Herein we investigate how the oxygen content in hot isostatically pressed (HIP'd) 316L stainless steel affects the mechanical properties and tensile fracture behavior. This work follows on from previous studies, which aimed to understand the effect of oxygen content on the Charpy impact toughness of HIP'd steel. We expand on the work by performing room-temperature tensile testing on different heats of 316L stainless steel, which contain different levels of interstitial elements (carbon and nitrogen) as well as oxygen in the bulk material. Throughout the work we repeat the experiments on conventionally forged 316L steel as a reference material. The analysis of the work indicates that oxygen does not contribute to a measureable solution strengthening mechanism, as is the case with carbon and nitrogen in austenitic stainless steels (Werner in Mater Sci Eng A 101:93-98, 1988). Neither does oxygen, in the form of oxide inclusions, contribute to precipitation hardening due to the size and spacing of particles. However, the oxide particles do influence fracture behavior; fractography of the failed tension test specimens indicates that the average ductile dimple size is related to the oxygen content in the bulk material, the results of which support an on-going hypothesis relating oxygen content in HIP'd steels to their fracture mechanisms by providing additional sites for the initiation of ductile damage in the form of voids. 13. Optimizing the Synthesis of Alumina Inserts Using Hot Isostatic Pressing (HIP) Science.gov (United States) Ariff, T. F.; Azhar, A. Z.; Sariff, M. N.; Rasid, S. N.; Zahari, S. Z.; Bahar, R.; Karim, M.; Nurul Amin, AKM 2018-01-01 Alumina or Aluminium Oxide (Al2O3) is well known for its high strength and hardness. Its low heat retention and low specific heat characteristics make it attractive to be used widely as a cutting tool for grinding, milling and turning processes. Various synthesis methods have been used for the purpose of enhancing the properties of the alumina inserts. However, the optimization process using Hot Isostatic Pressing (HIP) has not been performed. This research aims in finding the optimum parameters in synthesizing the alumina inserts (98Al2O3 1.6ZrO2 0.4MgO, 93Al2O3 6.4ZrO2 0.6MgO and 85Al2O3 14.5ZrO2 0.5MgO) using HIP at different temperatures (1200, 1250 and 1300°C) and sintering time (10, 30 and 60 minutes). Hardness, density, shrinkage and microstructure using SEM were analysed. The optimum sintering condition for the alumina insert was found in 98Al2O3 1.6ZrO2 0.4MgO sintered at 1300°C for 60 minutes for it exhibited the highest values of hardness (1917HV), density (3.95g/cm3), shrinkage (9.6%). 14. Cyclic fatigue resistance of yttria-stabilized tetragonal zirconia polycrystals with hot isostatic press processing. Science.gov (United States) Koyama, Taku; Sato, Toru; Yoshinari, Masao 2012-01-01 This study investigated the influence of surface roughness and cyclic loading on fatigue resistance in Y-TZP subjected to hot isostatic pressing (HIP). Fifty Y-TZP cylinders 3.0 mm in diameter were divided into Group A (polished by centerless method; TZP-CP) or Group B (blasted and acid-etched: TZP-SB150E). Twenty five cp-titanium cylinders (Ti-SB150E) were used as a control. Static and cyclic tests were carried out according to ISO 14801. The cyclic fatigue test was performed in distilled water at 37°C. Surface morphology and roughness as well as crystal phase on the surfaces were also evaluated. Fracture force under the static test was 1,765N (TZP-CP), 1,220N (TZP-SB150E), and 850 N (yield force, Ti-SB150E). Fracture values under the cyclic test decreased to approximately 70% of those under the static tests. These results indicate that HIPed Y-TZP with a 3.0-mm diameter has sufficient durability for application to dental implants. 15. A study on improving mechanical properties of porous HA tissue engineering scaffolds by hot isostatic pressing International Nuclear Information System (INIS) Zhao Jing; Xiao Suguang; Lu Xiong; Wang Jianxin; Weng Jie 2006-01-01 Various interconnected porous hydroxyapatite (HA) ceramic scaffolds are universally used to induct the tissue growth for bone repair and replacement, and serve to support the adhesion, transfer, proliferation and differentiation of cells. Impregnation of polyurethane sponges with a ceramic slurry is adopted to produce highly porous HA ceramic scaffolds with a 3D interconnected structure. However, high porosity always accompanies a decrease in the strength of the HA ceramic scaffolds. Therefore, it is significant to improve the strength of the HA ceramic scaffolds with highly interconnected porosity so that they are more suitable in clinical applications. In this work, highly porous HA ceramic scaffolds are first produced by the polymer impregnation approach, and subsequently further sintered by hot isostatic pressing (HIP). The phase composition, macro- and micro-porous structure, sintering and mechanical properties of the porous HA scaffolds are investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM), nanoindentation analysis and compressive test. The experimental results show that the nanohardness and compressive strength of HIP-sintered porous HA ceramics are higher than those of commonly sintered HA scaffolds. The HIP technique can effectively improve the sintering property and densification of porous HA ceramic scaffolds, so inducing an increase in the compression strength 16. High temperature mechanical performance of a hot isostatically pressed silicon nitride Energy Technology Data Exchange (ETDEWEB) Wereszczak, A.A.; Ferber, M.K.; Jenkins, M.G.; Lin, C.K.J. [and others 1996-01-01 Silicon nitride ceramics are an attractive material of choice for designers and manufacturers of advanced gas turbine engine components for many reasons. These materials typically have potentially high temperatures of usefulness (up to 1400{degrees}C), are chemically inert, have a relatively low specific gravity (important for inertial effects), and are good thermal conductors (i.e., resistant to thermal shock). In order for manufacturers to take advantage of these inherent properties of silicon nitride, the high-temperature mechanical performance of the material must first be characterized. The mechanical response of silicon nitride to static, dynamic, and cyclic conditions at elevated temperatures, along with reliable and representative data, is critical information that gas turbine engine designers and manufacturers require for the confident insertion of silicon nitride components into gas turbine engines. This final report describes the high-temperature mechanical characterization and analyses that were conducted on a candidate structural silicon nitride ceramic. The high-temperature strength, static fatigue (creep rupture), and dynamic and cyclic fatigue performance were characterized. The efforts put forth were part of Work Breakdown Structure Subelement 3.2.1, {open_quotes}Rotor Data Base Generation.{close_quotes} PY6 is comparable to other hot isostatically pressed (HIPed) silicon nitrides currently being considered for advanced gas turbine engine applications. 17. Microstructure and thermal conductivity of Mo-TiC cermets processed by hot isostatic pressing International Nuclear Information System (INIS) Le Flem, Marion; Allemand, Alexandre; Urvoy, Stephane; Cedat, Denis; Rey, Colette 2008-01-01 In the scope of refractory material development for structural applications in the core of future nuclear reactors (gas fast reactors working between 500 o C and at least 800 o C in nominal conditions and up to 1650 o C in accidental scenarios), five Mo-TiC cermets, and single-phase TiC and Mo, were processed by hot isostatic pressing. Starting TiC volume contents were 0%, 12.5%, 25%, 37.5%, 50%, 75% and 100%. First, high dense specimens were characterized in terms of microstructure, composition and phase volume fractions. Cermets exhibited two phases in agreement with phase diagram previsions (Mo-TiC 1-2at.% and TiC-Mo 10-15at.% ), and a residual non-reacted TiC-rich phase (TiC-Mo 1at.% ). Second, heat capacity and thermal diffusivity were measured up to 1000 o C which allowed to evaluate the thermal conductivity of each cermet: this lays between TiC conductivity (12-18 W/m K) and Mo conductivity (95-125 W/m K), thermal properties continuously decreasing with starting TiC content. An analytical approach based on the volume fraction and properties of each constituent allowed to highlight the existence of thermal resistance at the interphases at low temperature 18. Effect of reduced cobalt contents on hot isostatically pressed powder metallurgy U-700 alloys Science.gov (United States) Harf, F. H. 1982-01-01 The effect of reducing the cobalt content of prealloyed powders of UDIMET 700 (U-700) alloys to 12.7, 8.6, 4.3, and 0% was examined. The powders were hot isostatically pressed into billets, which were given heat treatments appropriate for turbine disks, namely partial solutioning at temperatures below the gamma prime solvus and four step aging treatments. Chemical analyses, metallographic examinations, and X-ray diffraction measurements were performed on the materials. Minor effects on gamma prime content and on room temperature and 650 C tensile properties were observed. Creep rupture lives at 650 C reached a maximum at the 8.4% concentration, while at 760 C a maximum in life was reached at the 4.3% cobalt level. Minimum creep rates increased with decreasing cobalt content at both test temperatures. Extended exposures at 760 and 815 C resulted in decreased tensile strengths and rupture lives for all alloys. Evidence of sigma phase formation was also found. 19. The substitution of nickel for cobalt in hot isostatically pressed powder metallurgy UDIMET 700 alloys Science.gov (United States) Harf, F. H. 1985-01-01 Nickel was substituted in various proportions for cobalt in a series of five hot-isostatically-pressed powder metallurgy alloys based on the UDIMET 700 composition. These alloys were given 5-step heat treatments appropriate for use in turbine engine disks. The resultant microstructures displayed three distinct sizes of gamma-prime particles in a gamma matrix. The higher cobalt-content alloys contained larger amounts of the finest gamma-prime particles, and had the lowest gamma-gamma-prime lattice mismatch. While all alloys had approximately the same tensile properties at 25 and 650 gamma C, the rupture lives at 650 and 760 C peaked in the alloys with cobalt contents between 12.7 and 4.3 pct. Minimum creep rates increased as cobalt contents were lowered, suggesting their correlation with the gamma-prime particle size distribution and the gamma-gamma-prime mismatch. It was also found that, on overaging at temperatures higher than suitable for turbine disk use, the high cobalt-content alloys were prone to sigma phase formation. 20. Fundamental Aspects of Zeolite Waste Form Production by Hot Isostatic Pressing Energy Technology Data Exchange (ETDEWEB) Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jordan, Jacob A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States) 2017-02-01 The direct conversion of iodine-bearing sorbents into a stable waste form is a research topic of interest to the US Department of Energy. The removal of volatile radioactive 129I from the off-gas of a nuclear fuel reprocessing facility will be necessary in order to comply with the regulatory requirements that apply to facilities sited within the United States (Jubin et al., 2012a), and any iodine-containing media or solid sorbents generated by this process would contain 129I and would be destined for eventual geological disposal. While recovery of iodine from some sorbents is possible, a method to directly convert iodineloaded sorbents to a durable waste form with little or no additional waste materials being formed and a potentially reduced volume would be beneficial. To this end, recent studies have investigated the conversion of iodine-loaded silver mordenite (I-AgZ) directly to a waste form by hot isostatic pressing (HIPing) (Bruffey and Jubin, 2015). Silver mordenite (AgZ), of the zeolite class of minerals, is under consideration for use in adsorbing iodine from nuclear reprocessing off-gas streams. Direct conversion of I-AgZ by HIPing may provide the following benefits: (1) a waste form of high density that is tolerant to high temperatures, (2) a waste form that is not significantly chemically hazardous, and (3) a robust conversion process that requires no pretreatment. 1. An Assessment of the Ductile Fracture Behaviour of Hot Isostatically Pressed and Forged 304L Stainless Steel OpenAIRE Cooper, Adam; Smith, R. J.; Sherry, Andrew 2017-01-01 Type 300 austenitic stainless steel manufactured by hot isostatic pressing (HIP) has recently been shown to exhibit subtly different fracture behavior from that of equivalent graded forged steel, whereby the oxygen remaining in the component after HIP manifests itself in the austenite matrix as nonmetallic oxide inclusions. These inclusions facilitate fracture by acting as nucleation sites for the initiation, growth, and coalescence of microvoids in the plastically deforming austenite matrix.... 2. Investigation of hot- iso-static press process for tungsten target samples International Nuclear Information System (INIS) Xu Yongli; Zhang Jinquan; Li Huaqing 2006-01-01 Zr and stainless steel (S.S.) were selected respectively as the cladding materials of W target. The e-beam weld was used to prepare the W-Zr and W-S.S. small samples for hot iso-static press (HIP) process. The technology parameters of HIP were investigated at 1200, 1300, 1400 degree C and 180 MPa, respectively. The micro-morphology of the interface, diffusion depths and composition as well as their micro-hardness were observed and determined. The bonding of W-Zr and W-S.S. is very well under the testing conditions. There is no any pore or micro-crack in the interface, and there is no grain growth of W below 1400 degree C either. The diffusion of Zr to W at the interface of W-Zr is preferred during HIP process, and the diffusion depths under testing conditions are 6-13 μm. The diffusion of W and Fe is considerable at the interface of W-S.S. Its depth is about 13 μm, and the diffusion of Cr and Ni is mall. The hardness at the interface of W-Zr and W-S.S. shows that a diffusion layer is present for both interface. A part of stainless steel cladding was melted after HIP contained the oxygen absorber Zr at 1300 degree C and 180 MPa. Therefore, 1200 degree C and 180 MPa is suitable for W-S.S. without Zr, but 1300 or 1400 degree C and 180 MPa is better for W-Zr. (authors) 3. Comparative evaluation of electrical conductivity of hydroxyapatite ceramics densified through ramp and hold, spark plasma and post sinter Hot Isostatic Pressing routes Energy Technology Data Exchange (ETDEWEB) Buchi Suresh, M., E-mail: [email protected]; Biswas, P.; Mahender, V.; Johnson, Roy, E-mail: [email protected] 2017-01-01 Hydroxyapatite ceramics synthesized through sonochemical route were processed and densified through ramp & hold (R&H) and Spark Plasma Sintering (SPS) routes. The effect of processing route on the relative density and electrical conductivity were studied. Further, the samples were Hot Isostatically Pressed (HIP) under argon pressure at elevated temperature to further densify the sample. All these samples processed under different conditions were characterized by X-ray diffraction, Scanning Electron Microscopy and AC Conductivity. The samples have exhibited hydroxyapatite phase; however, microstructures exhibited distinctly different grain morphologies and grain sizes. AC impedance spectroscopic measurement was carried out on hydroxyapatite samples processed through different routes and the corresponding spectra were analyzed by the analogy to equivalent circuit involving resistors and capacitors. SPS sintered sample after HIPing has exhibited the highest conductivity. This can be attributed to the higher density in combination with finer grain sizes. Activation energy based on Arrhenius equation is calculated and the prominent conduction mechanism is proposed. - Highlights: • Hot Isostatic Pressing (HIP) of SPS and R&H processed samples has resulted into densities near to theoretical densities • No change in the crystal structure is observed in SPS and R&H samples before and after HIP treatment • SPS processed and HIP treated samples resulted into higher conductivities with smaller grain sizes and grain boundary area. 4. Justification and manufacturing quality assurance for the use of hot Isostatically pressed, reactor coolant system components in PWR plant International Nuclear Information System (INIS) Sulley, J. L.; Hookham, I. D. 2008-01-01 This paper presents an overview of the work undertaken by Rolls-Royce to introduce Hot Isostatically Pressed (HIP) components into Pressurised Water Reactor plant. It presents the work from a design justification and manufacturing quality assurance perspective, rather than from a pure metallurgical perspective, although some metallurgical and mechanical property comparisons with the traditional forged material are presented. Although the HIP process is not new, it was new in its application to Rolls-Royce designed nuclear reactor plant. In order to satisfy the regulatory requirement of 'Proven Engineering Practices' with regard to the introduction of new material processes, and to provide a robust manufacturing substantiation leg of a multi-legged safety case, Rolls-Royce has implemented an evolving, staged approach, starting with HIP bonding of solid valve seats into small bore valve pressure boundaries. This was followed by powder HIP consolidation of leak-limited, thin-walled toroids, and has culminated in the powder HIP consolidation of components, such as steam generator headers, large bore valves and pipe sections. The paper provides an overview of each of these stages and the approach taken with respect to justification. The paper describes the benefits that Rolls-Royce has realised so far through the introduction of HIPed components, and improvements planned for the future. Structural integrity benefits are described, such as improved grain structure, mechanical properties, and ultrasonic inspection. Project-based benefits are also described, such as provision of an alternative strategic sourcing route, cost and lead-time reduction. A full description is provided of key quality assurance steps applied to the process to ensure a high quality product is delivered commensurate with a high integrity nuclear application. 2008 Rolls-Royce plc. (authors) 5. Study of the mechanical properties of stainless steel 316LN prepared by hot isostatic compression. Influence of preparation parameters International Nuclear Information System (INIS) Couturier, Raphael 1999-01-01 This research thesis has been performed within an R and D programme which aimed at optimising and certifying the HIP process (hot isostatic pressing) from a technological as well as metallurgical point of view. The objective has been to improve dimensional reproducibility of fabricated parts, and metallurgical properties of the dense material. Reference parts are those belonging to PWR primary circuit, and are made in cast austenitic-ferritic steel. Thus, the objective has been to show that these parts can be beneficially fabricated by powder metallurgy in austenitic grade. A mock part (a primary circuit pump wheel at the 1/2 scale) has first been fabricated by HIP, and a more complex shape generator has been designed. The author reports the determination of microstructure and mechanical characteristics of the austenitic 316LN steel produced by HIP and used to fabricate mock parts and demonstrator parts, the study of the relationship between dense material properties and fabrication parameters (temperature, pressure, consolidation time), and the analysis of the consequences of an elaboration by HIP on the 316LN steel with comparison with forged parts. After a presentation of the Powder Metallurgy elaboration technique, the author reports a bibliographical study on the precipitation at Prior Particle Boundaries (PPB), reports the study of microstructure and mechanical properties of the HIPed 316LN, and discusses the possibility of a decrease of precipitation at PPBs by adjusting powder degassing or a granulometric sorting. The last part reports the extension of the study of steel coherence to a temperature range which encompasses the primary circuit operation temperature (350 C). Resilience tests are performed as well as mechanical tests on notched axisymmetric samples. A finite element calculation of these samples allows the validation of the use of a Thomson-type model to describe the emergence of defects which are typical of a steel elaborated by powder 6. Characterization of hot isostatically pressed Bi-Sr-Ca-Cu-O as a function of consolidation variables International Nuclear Information System (INIS) Goretta, K.C.; Miller, D.J.; Poeppel, R.B.; Nash, A.S. 1992-01-01 This paper reports that fully dense, bulk Bi 2 Sr 1.7 CaCu 2 O x superconductor pellets were made by hot isostatic pressing in an inert atmosphere. Electron microscopy revealed that rotation and bending of the platelike 2212 grains were responsible for much of the densification. Under processing conditions of 825 degrees C and 105 MPa, dense pellets were obtained in 15 min. Many dislocations, planar faults, and, perhaps, intergrowths of the Bi 2 Cr 2 CuO x phase were produced during pressing. The dislocations were largely present in subgrain boundaries when the pressing times were increased to 45-120 min 7. Pore annihilation in a single-crystal nickel-base superalloy during hot isostatic pressing: Experiment and modelling International Nuclear Information System (INIS) Epishin, Alexander; Fedelich, Bernard; Link, Thomas; Feldmann, Titus; Svetlov, Igor L. 2013-01-01 Pore annihilation during hot isostatic pressing (HIP) was investigated in the single-crystal nickel-base superalloy CMSX-4 experimentally by interrupted HIP tests at 1288 °C/103 MPa. The kinetics of pore annihilation was determined by density measurement and quantitative metallography. Transmission electron microscopy of a HIPed specimen showed that the pores shrink via dislocation movement on octahedral glide planes. Theoretically pore closure under HIP condition was modelled by the finite element method using crystal plasticity and large strain theories. The modelling gives a similar kinetics of pore annihilation as observed experimentally, however somewhat higher annihilation rate 8. Microstructural and mechanical characteristics of W–2Ti and W–1TiC processed by hot isostatic pressing Energy Technology Data Exchange (ETDEWEB) Muñoz, A., E-mail: [email protected] [Departamento de Física, Universidad Carlos III de Madrid, Avda. de la Universidad, 30, E28911 Leganés (Spain); Savoini, B. [Departamento de Física, Universidad Carlos III de Madrid, Avda. de la Universidad, 30, E28911 Leganés (Spain); Tejado, E. [Departamento de Ciencia de Materiales, E.T.S. I. de Ingenieros de Caminos, Canales y Puertos, Universidad Politécnica de Madrid, E28040 Madrid (Spain); Centro Nacional de Investigaciones Metalúrgicas (C.S.I.C), Av. Gregorio del Amo, 8, E2840 Madrid (Spain); Monge, M.A. [Departamento de Física, Universidad Carlos III de Madrid, Avda. de la Universidad, 30, E28911 Leganés (Spain); Pastor, J.Y. [Departamento de Ciencia de Materiales, E.T.S. I. de Ingenieros de Caminos, Canales y Puertos, Universidad Politécnica de Madrid, E28040 Madrid (Spain); Pareja, R. [Departamento de Física, Universidad Carlos III de Madrid, Avda. de la Universidad, 30, E28911 Leganés (Spain) 2014-12-15 W–2Ti and W–1TiC alloys were produced by mechanical alloying and consolidation by hot isostatic pressing. The composition and microstructural characteristics of these alloys were studied by X-ray diffraction, energy dispersion spectroscopy and scanning electron microscopy. The mechanical behavior of the consolidated alloys was characterized by microhardness measurements and three point bending tests. The mechanical characteristics of the W–2Ti alloy appear to be related to solution hardening. In W–1TiC, the residual porosity should be responsible for the poor behavior observed in comparison with W–2Ti. 9. Microstructural and mechanical characteristics of W–2Ti and W–1TiC processed by hot isostatic pressing International Nuclear Information System (INIS) Muñoz, A.; Savoini, B.; Tejado, E.; Monge, M.A.; Pastor, J.Y.; Pareja, R. 2014-01-01 W–2Ti and W–1TiC alloys were produced by mechanical alloying and consolidation by hot isostatic pressing. The composition and microstructural characteristics of these alloys were studied by X-ray diffraction, energy dispersion spectroscopy and scanning electron microscopy. The mechanical behavior of the consolidated alloys was characterized by microhardness measurements and three point bending tests. The mechanical characteristics of the W–2Ti alloy appear to be related to solution hardening. In W–1TiC, the residual porosity should be responsible for the poor behavior observed in comparison with W–2Ti 10. Formation of ultra-fine grained TiC-dispersed SUS316L by ball-milling and their consolidation by hot isostatic pressing International Nuclear Information System (INIS) Zheng, Yongjia; Yamasaki, Tohru; Fukami, Takeshi; Mitamura, Tohru; Terasawa, Mititaka 2003-01-01 In order to overcome the irradiation embrittlement in austenitic stainless steels, ultra-fine grained SUS316L steels with very fine TiC particles have been developed. The SUS316-TiC nanocomposite powders having 1.0 to 2.0 mass%TiC were prepared by ball-milling SUS316-TiC powder mixtures for 125h in an argon gas atmosphere. The milled powders were consolidated by hot isostatic pressing (HIP) under a pressure of 200 MPa at temperature between 700-1000degC, and the bulk materials with crystallite size ranging between 100-400 nm have been produced. The possibility of using fine-grained TiC particles for pinning grain boundaries and thereby to maintain the ultra-fine grained structures has been discussed. (author) 11. Interface analysis of A1 matrix composites produced by hot isostatic pressing, squeeze casting and semi-solid processing International Nuclear Information System (INIS) Shamsul, J.B.; Zainal Arifin Ahmad; Faaizulaswad, M.S.; Azmi, R. 2000-01-01 The interface analysis has been carried out an aluminium based composites system produced by hot isostatic pressing, squeeze casting and semi-solid processing. A range of different fabrication techniques has been used to produce different types of microstructure of Al 2124 (Al-Cu-Mg) reinforced with 5 weight % SiC particles. Blending followed by hot isostatic pressing is used to fabricate composite I. Composite II was 6061 (Al-Si-Mg) wrought aluminium alloy reinforced with fibres of alumina-silica (V f = 0.58) and fabricated by squeeze casting. Finally, A356 (AlSi7Mg0.3) alloy was reinforced with 20 Vol.% of SiC particles (13 μm) and namely as composite III. Composite III is fabricated by semi-solid processing. Interface analysis was done by optical microscopy, scanning and transmission electron microscopy. Composite I exhibited good interface bonding and dislocation was also observed near the interface. Elements such as Al, Fe, Cr, Mn were found near the interface of composite II and intermetallic of iron rich inclusion and Mg 2 Si were observed near the interface of composite III. (Author) 12. An Assessment of the Ductile Fracture Behavior of Hot Isostatically Pressed and Forged 304L Stainless Steel Science.gov (United States) Cooper, A. J.; Smith, R. J.; Sherry, A. H. 2017-05-01 Type 300 austenitic stainless steel manufactured by hot isostatic pressing (HIP) has recently been shown to exhibit subtly different fracture behavior from that of equivalent graded forged steel, whereby the oxygen remaining in the component after HIP manifests itself in the austenite matrix as nonmetallic oxide inclusions. These inclusions facilitate fracture by acting as nucleation sites for the initiation, growth, and coalescence of microvoids in the plastically deforming austenite matrix. Here, we perform analyses based on the Rice-Tracey (RT) void growth model, supported by instrumented Charpy and J-integral fracture toughness testing at ambient temperature, to characterize the degree of void growth ahead of both a V-notch and crack in 304L stainless steel. We show that the hot isostatically pressed (HIP'd) 304L steel exhibits a lower critical void growth at the onset of fracture than that observed in forged 304L steel, which ultimately results in HIP'd steel exhibiting lower fracture toughness at initiation and impact toughness. Although the reduction in toughness of HIP'd steel is not detrimental to its use, due to the steel's sufficiently high toughness, the study does indicate that HIP'd and forged 304L steel behave as subtly different materials at a microstructural level with respect to their fracture behavior. 13. Effect of Hot-isostatic Pressing on Microstructure and Mechanical Properties of Second Generation Single Crystal Superalloy DD6 Directory of Open Access Journals (Sweden) GUO Hui-ming 2016-10-01 Full Text Available Effects of the hot-isostatic pressing (HIP temperature (1280,1300,1320℃ on microstructures and mechanical properties of a second generation single crystal superalloy DD6 were investigated. The results show that the HIP treatment significantly decrease the cast porosity number of DD6 compared with standard treated specimens. Especially, the cast porosity volume fraction is deceased from 0.31% to 0.04% after the HIP treatment of 1300℃/100MPa, 4h. The cast eutectic volume fractions are remarkably reduced with increasing HIP temperature. The HIP treatments nearly unchanged the creep lives, While they greatly promote the low cycle fatigue lives. The elimination of cast microspores using the HIP treatment of 1300℃/100MPa, 4h result in the inhibition of crack initiation during fatigue and improve the low cycle fatigue lives one order of magnitude larger than that after standard heat treatment. 14. Influence of surface treatment of yttria-stabilized tetragonal zirconia polycrystal with hot isostatic pressing on cyclic fatigue strength. Science.gov (United States) Iijima, Toshihiko; Homma, Shinya; Sekine, Hideshi; Sasaki, Hodaka; Yajima, Yasutomo; Yoshinari, Masao 2013-01-01 Hot isostatic pressing processed yttria-stabilized tetragonal zirconia polycrystal (HIP Y-TZP) has the potential for application to implants due to its high mechanical performance. The aim of this study was to investigate the influence of surface treatment of HIP Y-TZP on cyclic fatigue strength. HIP Y-TZP specimens were subjected to different surface treatments. Biaxial flexural strength was determined by both static and cyclic fatigue testing. In the cyclic fatigue test, the load was applied at a frequency of 10 Hz for 10(6) cycles in distilled water at 37°C. The surface morphology, roughness, and crystal phase of the surfaces were also evaluated. The cyclic fatigue strength (888 MPa) of HIP Y-TZP with sandblasting and acid-etching was more than twice that of Y-TZP as specified in ISO 13356 for surgical implants (320 MPa), indicating the clinical potential of this material. 15. Verification of the effect of surface preparation on Hot Isostatic Pressing diffusion bonding joints of CLAM steel Energy Technology Data Exchange (ETDEWEB) Zhao, Yanyun [University of Science and Technology of China, Hefei, Anhui 230027 (China); Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Li, Chunjing, E-mail: [email protected] [Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Huang, Bo; Liu, Shaojun [Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Huang, Qunying [University of Science and Technology of China, Hefei, Anhui 230027 (China); Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui 230031 (China) 2014-12-15 Hot Isostatic Pressing (HIP) diffusion bonding with CLAM steel is the primary candidate fabrication technique for the first wall (FW) of DFLL-TBM. Surface state is one of the key factors for the joints quality. The effect of surface state prepared with grinder and miller on HIP diffusion bonding joints of CLAM steel was investigated. HIP diffusion bonding was performed at 140 MPa and 1373 K within 3 h. The mechanical properties of the joints were investigated with instrumented Charpy V-notch impact tests and the microstructures of the joints were analyzed with scanning electron microscopy (SEM). The results showed that the milled samples with fine surface roughness were more suitable for CLAM steel HIP diffusion bonding. 16. Pressure slip casting and cold isostatic pressing of aluminum titanate green ceramics: A comparative evaluation Directory of Open Access Journals (Sweden) Ramanathan Papitha 2013-12-01 Full Text Available Aluminum titanate (Al2TiO5 green bodies were prepared from mixture of titania and alumina powders with different particle sizes by conventional slip casting (CSC, pressure slip casting (PSC and cold isostatic pressing (CIP. Precursor-powder mixtures were evaluated with respect to the powder properties, flow behaviours and shaping parameters. Green densities were measured and correlated with the fractographs. A substantial increase in green densities up to 60 %TD (theoretical density of 4.02 g/cm3, calculated based on rule of mixtures is observed with the application of 2–3 MPa pressure with PSC. While particle size distribution and solid loading are the most influential parameters in the case of CSC, with PSC pressure also plays a key role in achieving the higher green densities. Being a dry process, high pressure of > 100 MPa for CIP is essential to achieve densities in the range of 60–65 %TD. Slip pressurization under PSC conditions facilitate the rearrangement of particles through rolling, twisting and interlocking unlike CIP processing where pressure is needed to overcome the inter-particle friction. 17. Hot-isostatic pressing of U-10Zr by grain boundary diffusion and creep cavitation. Part 2: Theory and data analysis International Nuclear Information System (INIS) McDeavitt, S.M.; Solomon, A.A. 1997-01-01 Uranium-10 wt % zirconium (U-10Zr) is a fuel alloy that has been used in the Experimental Breeder Reactor-II (EBR-II). The high burnup that was desired in this fuel system made high demands on the mechanical compatibility between fuel and cladding both during normal operation and during safety-related transients when rapid differential expansion may cause high stresses. In general, this mechanical stress can be reduced by cladding deformation if the cladding is sufficiently ductile at high burnup, and/or by fuel hot-pressing. Fortunately, the fuel is very porous when it contacts the cladding, but this porosity gradually fills with solid fission products (primarily lanthanides) that may limit the fuel's compressibility. If the porosity remains open, gaseous fission products are released and the porous fuel creeps rather than hot-presses under contact stresses. If the pores are closed by sintering or by solid fission products, the porous fuel will hot-isostatic press (HIP), as represented by the models to be discussed. HIP experiments performed at 700 C on U-10Zr samples with different impurity phase contents (Part 1) are analyzed in terms of several creep cavitation models. The coupled diffusion/creep cavitation model of Chen and Argon shows good quantitative agreement with measured HIP rates for hydride- and metal-derived U-10Zr materials, assuming that pores are uniformly distributed on grain boundaries and are of modal size, and that far-field strain rates are negligible. The analysis predicts, for the first time, an asymmetry between HIP and swelling at identical pressure-induced driving forces due to differences in grain boundary stresses. The differences in compressibility of hydride- and metal-derived U-10Zr can be partially explained by differences in pore size and spacing. The relevance of the experiments to description of in-reactor densification under external pressure or contact stress due to fuel/cladding mechanical interaction is discussed 18. Improvement of nuclear reactor component materials by application of hot isostatic processing (HIP). Survey report on Phase 1 International Nuclear Information System (INIS) Mueller, J.J. 1975-12-01 The report summarizes the results of an EPRI-sponsored state-of-the-art survey of hot isostatic processing (HIP). The purpose of the study was to identify potential nuclear plant applications of HIP with high pay-off through improvement in component quality and reliability. The survey shows that HIP will reduce cost and manufacturing time and improve quality and ease of nondestructive examination of all castings for which porosity is a problem. Nuclear valves are a prime example. Tubing, pipe, and sheet and bar present other possibilities of somewhat less immediate promise. This report includes a review of some of the EPRI motivations for undertaking this research; a brief explanation of HIP, the survey methodology exployed; the basic operations in the processes studied; a review of the historical applications of HIP to problem areas consistent with those addressed in the survey; the results of the survey and associated analyses of the problems; and the recommendations and justifications for the Phase II program 19. Microstructure and properties of diffusion bonded Ti-6Al-4V parts using brazing-assisted hot isostatic pressing International Nuclear Information System (INIS) Wu, Z.; Mei, J.; Voice, W.; Beech, Steve; Wu, X. 2011-01-01 Highlights: → A low cost method of diffusion bonding has been developed for complex-shaped components of Ti6Al4V. → Vacuum brazing has been used to seal the periphery to allow encapsulation-free HIPping. → The tensile properties of the bonds are comparable with those of the bulk material, but the fatigue life was slightly reduced. - Abstract: Ti-6Al-4V couples have been diffusion bonded by hot isostatic pressing (HIPping) after vacuum brazing was used to seal the periphery of the bonding samples so that no encapsulation was required during HIPping. Analytical scanning electron microscopy was used to assess the microstructure of the HIPped interface and tensile and fatigue properties of bonded samples were compared with those of the bulk starting material. The tensile properties of the bonds were shown to be comparable with those of the bulk material, but the fatigue life was slightly downgraded. The fatigue fractures were initiated by inclusions on the bonding interface, caused by contamination before bonding, but the fatigue cracks did not propagate along the bonding interface indicating a strong bond. It is concluded that this technique of vacuum brazing plus HIPping could be used for encapsulation-free HIPping to produce complex-shaped components. 20. Inversion defects in MgAl2O4 elaborated by pressureless sintering, pressureless sintering plus hot isostatic pressing, and spark plasma sintering International Nuclear Information System (INIS) Mussi, A.; Granger, G. Bernard; Addad, A.; Benameur, N.; Beclin, F.; Bataille, A. 2009-01-01 The distribution of inversion defects of Al was investigated in dense magnesium-aluminate spinel elaborated by pressureless sintering, pressureless sintering plus hot isostatic pressing, and spark plasma sintering. This study was conducted by energy electron loss spectroscopy analyses and more particularly by energy loss near edge structure investigations of the Al-L 2,3 edge. Several aspects are discussed with the purpose of understanding why charged defects dispersal reveals a special configuration. 1. Effect of Tooling Material on the Internal Surface Quality of Ti6Al4V Parts Fabricated by Hot Isostatic Pressing Science.gov (United States) Cai, Chao; Song, Bo; Wei, Qingsong; Yan, Wu; Xue, Pengju; Shi, Yusheng 2017-01-01 For the net-shape hot isostatic pressing (HIP) process, control of the internal surface roughness of as-HIPped parts remains a challenge for practical engineering. To reveal the evolution mechanism of the internal surface of the parts during the HIP process, the effect of different tooling materials (H13, T8, Cr12 steel, and graphite) as internal cores on the interfacial diffusion and surface roughness was systematically studied. 2. Manufacturing and mechanical property test of the large-scale oxide dispersion strengthened martensitic mother tube by hot isostatic pressing and hot extrusion process International Nuclear Information System (INIS) Narita, Takeshi; Ukai, Shigeharu; Kaito, Takeji; Ohtsuka, Satoshi; Fujiwara, Masayuki 2003-09-01 Mass production capability of Oxide Dispersion Strengthened (ODS) ferritic steel cladding (9Cr) is evaluated in the Phase II of the Feasibility Studies on Commercialized Fast Reactor Cycle System. The cost for manufacturing mother tube is a dominant factor in the total cost for manufacturing ODS ferritic cladding. In this study, the large-scale 9Cr-ODS martensitic mother tube was produced by overseas supplier with mass production equipments for commercialized ODS steels. The process of manufacturing the ODS mother tube consists of raw material powder production, mechanical alloying by high energy ball mill, hot isostatic pressing(HIP), and hot extrusion. Following results were obtained in this study. (1) Micro structure of the ODS steels is equivalent to that of domestic products, and fine oxides are uniformly distributed. The mechanical alloying by large capacity (1 ton) ball mill can be satisfactorily carried out. (2) A large scale mother tube (65 mm OD x 48 mm ID x 10,000 mm L), which can produce about 60 pieces of 3 m length ODS ferritic claddings by four times cold rolling, have been successfully manufactured through HIP and Hot Extrusion process. (3) Rough surface of the mother tubes produced in this study can be improved by selecting the reasonable hot extrusion condition. (4) Hardness and tensile strength of the manufactured ODS steels are lower than domestic products with same chemical composition. This is owing to the high aluminum content in the product, and those properties could be improved by decreasing the aluminum content in the raw material powder. (author) 3. Ceramic containers for spent nuclear fuel. II. Reactions between TiO2 and the steel canning during hot isostatic processing International Nuclear Information System (INIS) Bergman, B.; Forberg, S. 1984-01-01 Rutile was selected for some practical studies of processing and properties of ceramic containers. Hot isostatic pressing at 1280 0 C has resulted in reaction zones between the TiO 2 powder and the steel canning. The phases ilmenite, pseudobrookite, rutile, and iron have been identified by x-ray diffraction and by microprobe analysis. The microstructures have been interpreted by classical metallographic methods, and some microstructures obtained by hot pressing and rapid cooling have also been examined for purposes of comparison. Some implications of the microstructures have been discussed in terms of microcracking and slow crack growth. 13 refs., 7 figs 4. Hot isostatically pressed (HIPed) thick-walled component for a pressurised water reactor (PWR) application International Nuclear Information System (INIS) Hookham, I.; Burdett, B.; Bridger, K.; Sulley, J.L. 2009-01-01 This paper presents the work conducted to justify and provide a quality assured HIPed thick-walled component for a PWR application; the component being designed and manufactured by Rolls-Royce. Rolls-Royce has previously published (ICAPP 08) its overall, staged approach to the introduction of powder HIPed components; starting with thin-walled, leak limited pressure boundaries, and culminating in the use of the powder HIPed process for thick walled components. This paper presents details specific to a thick walled pressure vessel component. Results are presented of non-destructive and destructive examinations of one of a batch of components. Mechanical testing and metallurgical examination results of sample material taken from different sections of the component are presented. A full range of test results is provided covering, as examples: tensile, Charpy impact and sensitization susceptibility. Differences in weldability between the HIPed and the previous forged form are also documented. (author) 5. Microstructural and Microhardness Evolution from Homogenization and Hot Isostatic Pressing on Selective Laser Melted Inconel 718: Structure, Texture, and Phases Directory of Open Access Journals (Sweden) Raiyan Seede 2018-05-01 Full Text Available In this work, the microstructure, texture, phases, and microhardness of 45° printed (with respect to the build direction homogenized, and hot isostatically pressed (HIP cylindrical IN718 specimens are investigated. Phase morphology, grain size, microhardness, and crystallographic texture at the bottom of each specimen differ from those of the top due to changes in cooling rate. High cooling rates during the printing process generated a columnar grain structure parallel to the building direction in the as-printed condition with a texture transition from (001 orientation at the bottom of the specimen to (111 orientation towards the specimen top based on EBSD analysis. A mixed columnar and equiaxed grain structure associated with about a 15% reduction in texture is achieved after homogenization treatment. HIP treatment caused significant grain coarsening, and engendered equiaxed grains with an average diameter of 154.8 µm. These treatments promoted the growth of δ-phase (Ni3Nb and MC-type brittle (Ti, NbC carbides at grain boundaries. Laves phase (Fe2Nb was also observed in the as-printed and homogenized specimens. Ostwald ripening of (Ti, NbC carbides caused excessive grain growth at the bottom of the HIPed IN718 specimens, while smaller grains were observed at their top. Microhardness in the as-fabricated specimens was 236.9 HV and increased in the homogenized specimens by 19.3% to 282.6 HV due to more even distribution of secondary precipitates, and the nucleation of smaller grains. A 36.1% reduction in microhardness to 180.5 HV was found in the HIPed condition due to γ ″ phase dissolution and differences in grain morphology. 6. Influences of hot-isostatic-pressing temperature on microstructure, tensile properties and tensile fracture mode of Inconel 718 powder compact International Nuclear Information System (INIS) Chang, Litao; Sun, Wenru; Cui, Yuyou; Yang, Rui 2014-01-01 Inconel 718 powders have been hot-isostatic-pressed (HIPed) at representative temperatures to investigate the variations in microstructure, tensile properties and tensile fracture mode of the powder compact. Microstructure of the powder compacts were characterized by optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and so on. The results showed that the interdendritic precipitates inherited from the powders were partially retained in the powder compacts when the powders were HIPed at or below 1210 °C but were eliminated when HIPed at and above 1260 °C. The grain size uniformity of the powder compacts first increases and then decreases with increasing HIPing temperature. Prior particle boundaries (PPBs) were observed in the powder compacts HIPed at and below 1260 °C but was eliminated when HIPed at 1275 °C. The PPBs were decorated with carbide particles, the amount of the carbide particles at the PPBs decreases with increasing HIPing temperature. Most of the PPBs were pinned by the carbide particles in the compacts HIPed at 1140 °C. When the HIPing temperature was increased to 1210 °C and 1260 °C, a large number of PPBs de-pinned and moved beyond the pinning carbide particles, leading to grain growth and leaving carbide particles at the site of the original PPBs within the new grains. With increasing HIPing temperature, the 0.2% yield strength of the powder compacts at 650 °C decreases, the tensile elongation increases, and the tensile fracture mode changed from inter-particle dominant fracture to fully dimple ductile fracture 7. Comparison of structure, morphology, and leach characteristics of multi-phase ceramics produced via melt processing and hot isostatic pressing Science.gov (United States) Dandeneau, Christopher S.; Hong, Tao; Brinkman, Kyle S.; Vance, Eric R.; Amoroso, Jake W. 2018-04-01 Melt processing of multi-phase ceramic waste forms offers potential advantages over traditional solid-state synthesis methods given both the prevalence of melters currently in use and the ability to reduce the possibility of airborne radionuclide contamination. In this work, multi-phase ceramics with a targeted hollandite composition of Ba1.0Cs0.3Cr1.0Al0.3Fe1.0Ti5.7O16 were fabricated by melt processing at 1675 °C and hot isostatic pressing (HIP) at 1250 and 1300 °C. X-ray diffraction analysis (XRD) confirmed hollandite as the major phase in all specimens. Zirconolite/pyrochlore peaks and weaker perovskite reflections were observed after melt processing, while HIP samples displayed prominent perovskite peaks and low-intensity zirconolite reflections. Melt processing produced specimens with large (>50 μm) well-defined hollandite grains, while HIP yielded samples with a more fine-grained morphology. Elemental analysis showed "islands" rich in Cs and Ti across the surface of the 1300 °C HIP sample, suggesting partial melting and partitioning of Cs into multiple phases. Photoemission data revealed multiple Cs 3d spin-orbit pairs for the HIP samples, with the lower binding energy doublets likely corresponding to Cs located in more leachable phases. Among all specimens examined, the melt-processed sample exhibited the lowest fractional release rates for Rb and Cs. However, the retention of Sr and Mo was greater in the HIP specimens. 8. Influences of hot-isostatic-pressing temperature on microstructure, tensile properties and tensile fracture mode of Inconel 718 powder compact Energy Technology Data Exchange (ETDEWEB) Chang, Litao [Institute of Metal Research, Chinese Academy of Sciences, Shenyang (China); University of Chinese Academy of Sciences, Beijing (China); Sun, Wenru; Cui, Yuyou [Institute of Metal Research, Chinese Academy of Sciences, Shenyang (China); Yang, Rui, E-mail: [email protected] [Institute of Metal Research, Chinese Academy of Sciences, Shenyang (China) 2014-04-01 Inconel 718 powders have been hot-isostatic-pressed (HIPed) at representative temperatures to investigate the variations in microstructure, tensile properties and tensile fracture mode of the powder compact. Microstructure of the powder compacts were characterized by optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and so on. The results showed that the interdendritic precipitates inherited from the powders were partially retained in the powder compacts when the powders were HIPed at or below 1210 °C but were eliminated when HIPed at and above 1260 °C. The grain size uniformity of the powder compacts first increases and then decreases with increasing HIPing temperature. Prior particle boundaries (PPBs) were observed in the powder compacts HIPed at and below 1260 °C but was eliminated when HIPed at 1275 °C. The PPBs were decorated with carbide particles, the amount of the carbide particles at the PPBs decreases with increasing HIPing temperature. Most of the PPBs were pinned by the carbide particles in the compacts HIPed at 1140 °C. When the HIPing temperature was increased to 1210 °C and 1260 °C, a large number of PPBs de-pinned and moved beyond the pinning carbide particles, leading to grain growth and leaving carbide particles at the site of the original PPBs within the new grains. With increasing HIPing temperature, the 0.2% yield strength of the powder compacts at 650 °C decreases, the tensile elongation increases, and the tensile fracture mode changed from inter-particle dominant fracture to fully dimple ductile fracture. 9. Impact properties of reduced activation ferritic/martensitic steel, F82H jointed by hot isostatic pressing Energy Technology Data Exchange (ETDEWEB) Ogiwara, H.; Tanigawa, H. [Japan Atomic Energy Agency, Tokai-mura, Naga-gun, Ibaraki-ken (Japan); Hirose, T. [Blanket Engineering Group, Japan Atomic Energy Agency, Naka, Ibaraki (Japan); Enoeda, M. [Naka Fusion Research Establishment, J.A.E.R.I., Japan Atomic Energy Research Institute, Ibaraki-ken (Japan); Kohyama, A. [Kyoto Univ., lnstitute of Advanced Energy (Japan) 2007-07-01 Full text of publication follows: Reduced-activation ferritic/martensitic steels are the leading candidate structural material for the blanket system of fusion reactors. The important issue at the current stage is the finalization of a detailed manufacturing specification for ITER test blanket module. Hot isostatic pressing (HIP) process is one of the most important methods to fabricate the first wall with cooling channels. The objective of this paper is to optimize HIP condition to obtain the excellent joints mechanical properties. The materials used were F82H steels. The joint was produced by solid state HIP method. Before HIP treatments, specimens were heated in vacuum condition to out-gas. This treatment was conducted to decrease oxidation on the surfaces. HIP treatments were carried out for 2 h at 1100 deg. C - 140 MPa. The specimens were normalized at 960 deg. C for 0.5 h and tempered at 750 deg. C for 1.5 h. The bonding interface was characterized by scanning electron microscopy. Charpy impact tests and tensile tests were conducted to evaluate the mechanical properties of the HIP joint. Impact tests revealed that there were no significant differences in the ductile-brittle transition temperatures of HIP jointed specimens and base metal specimens, but the upper-shelf energy (USE) of the HIP joint specimens at room temperature was only about 10% of that of the base metal specimens. SEM observations of the fracture surface of HIP joint specimens revealed that a large number of oxides were formed on the HIP joint. This result indicates that oxides formed on the HIP joint are the dominant factor of the impact properties. Based on these results, the pre-HIP treatment conditions had been optimized to reduce the number of oxides, and USE of HIP joint specimens increased to about 50% of that of the base metal. The detailed analyses on the HIP joint microstructure will be reported. (authors) 10. Beryllium window flange for synchrotron radiation X-ray beamline fabricated by hot isostatic press method International Nuclear Information System (INIS) Asaoka, Seiji; Maezawa, Hideki; Nishida, Kiyotoshi; Sakamoto, Naoki. 1995-01-01 The synchrotron radiation experimental facilities in National Laboratory for High Energy Physics are the experimental facilities for joint utilization, that possess the positron storage ring of 2.5 GeV exclusively used for synchrotron radiation. Synchrotron radiation is led through a mainstay beam channel to the laboratory, and in the beam line of X-ray, it is used for experiment through the taking-out window made of beryllium. At this time, the function of the taking-out window is to shut off between the ultrahigh vacuum in the mainstay beam channel and the atmosphere, and to cut the low energy component of synchrotron radiation spectra. The experiment using X-ray is carried out mostly in the atmosphere. The design of the efficient cooling water channel which is compatible with the flange construction is important under the high thermal load of synchrotron radiation. The beryllium window flange for synchrotron radiation X-ray was made by HIP method, and the ultrahigh vacuum test, the high pressure water flow test and the actual machine test were carried out by heat cycle. The properties required for the window material, the requirement of the construction, the new development of HIP method, and the experiments for evaluating the manufactured beryllium window are described. (K.I.) 11. Effects of hot isostatic pressing on the elastic modulus and tensile properties of 316L parts made by powder bed laser fusion Energy Technology Data Exchange (ETDEWEB) Lavery, N.P., E-mail: [email protected] [Materials Research Centre, College of Engineering, Swansea University Bay Campus, Fabian Way, Swansea SA1 8EP (United Kingdom); Zienkiewicz Centre for Computational Engineering, College of Engineering, Swansea University Bay Campus, Fabian Way, Swansea SA1 8EP (United Kingdom); Cherry, J.; Mehmood, S. [Materials Research Centre, College of Engineering, Swansea University Bay Campus, Fabian Way, Swansea SA1 8EP (United Kingdom); Zienkiewicz Centre for Computational Engineering, College of Engineering, Swansea University Bay Campus, Fabian Way, Swansea SA1 8EP (United Kingdom); Davies, H. [Materials Research Centre, College of Engineering, Swansea University Bay Campus, Fabian Way, Swansea SA1 8EP (United Kingdom); Girling, B.; Sackett, E. [Materials Research Centre, College of Engineering, Swansea University Bay Campus, Fabian Way, Swansea SA1 8EP (United Kingdom); Zienkiewicz Centre for Computational Engineering, College of Engineering, Swansea University Bay Campus, Fabian Way, Swansea SA1 8EP (United Kingdom); Brown, S.G.R. [Materials Research Centre, College of Engineering, Swansea University Bay Campus, Fabian Way, Swansea SA1 8EP (United Kingdom); Sienz, J. [Zienkiewicz Centre for Computational Engineering, College of Engineering, Swansea University Bay Campus, Fabian Way, Swansea SA1 8EP (United Kingdom) 2017-05-02 The microstructure and mechanical properties of 316L steel have been examined for parts built by a powder bed laser fusion process, which uses a laser to melt and build parts additively on a layer by layer basis. Relative density and porosity determined using various experimental techniques were correlated against laser energy density. Based on porosity sizes, morphology and distributions, the porosity was seen to transition between an irregular, highly directional porosity at the low laser energy density and a smaller, more rounded and randomly distributed porosity at higher laser energy density, thought to be caused by keyhole melting. In both cases, the porosity was reduced by hot isostatic pressing (HIP). High throughput ultrasound based measurements were used to calculate elasticity properties and show that the lower porosities from builds with higher energy densities have higher elasticity moduli in accordance with empirical relationships, and hot isostatic pressing improves the elasticity properties to levels associated with wrought/rolled 316L. However, even with hot isostatic pressing the best properties were obtained from samples with the lowest porosity in the as-built condition. A finite element stress analysis based on the porosity microstructures was undertaken, to understand the effect of pore size distributions and morphology on the Young's modulus. Over 1–5% porosity range angular porosity was found to reduce the Young's modulus by 5% more than rounded porosity. Experimentally measured Young's moduli for samples treated by HIP were closer to the rounded trends than the as-built samples, which were closer to angular trends. Tensile tests on specimens produced at optimised machine parameters displayed a high degree of anisotropy in the build direction and test variability for as-built parts, especially between vertical and horizontal build directions. The as-built properties were generally found to have a higher yield stress, but 12. Effects of hot isostatic pressing on the elastic modulus and tensile properties of 316L parts made by powder bed laser fusion International Nuclear Information System (INIS) Lavery, N.P.; Cherry, J.; Mehmood, S.; Davies, H.; Girling, B.; Sackett, E.; Brown, S.G.R.; Sienz, J. 2017-01-01 The microstructure and mechanical properties of 316L steel have been examined for parts built by a powder bed laser fusion process, which uses a laser to melt and build parts additively on a layer by layer basis. Relative density and porosity determined using various experimental techniques were correlated against laser energy density. Based on porosity sizes, morphology and distributions, the porosity was seen to transition between an irregular, highly directional porosity at the low laser energy density and a smaller, more rounded and randomly distributed porosity at higher laser energy density, thought to be caused by keyhole melting. In both cases, the porosity was reduced by hot isostatic pressing (HIP). High throughput ultrasound based measurements were used to calculate elasticity properties and show that the lower porosities from builds with higher energy densities have higher elasticity moduli in accordance with empirical relationships, and hot isostatic pressing improves the elasticity properties to levels associated with wrought/rolled 316L. However, even with hot isostatic pressing the best properties were obtained from samples with the lowest porosity in the as-built condition. A finite element stress analysis based on the porosity microstructures was undertaken, to understand the effect of pore size distributions and morphology on the Young's modulus. Over 1–5% porosity range angular porosity was found to reduce the Young's modulus by 5% more than rounded porosity. Experimentally measured Young's moduli for samples treated by HIP were closer to the rounded trends than the as-built samples, which were closer to angular trends. Tensile tests on specimens produced at optimised machine parameters displayed a high degree of anisotropy in the build direction and test variability for as-built parts, especially between vertical and horizontal build directions. The as-built properties were generally found to have a higher yield stress, but lower upper 13. Hot isostatically-pressed aluminosilicate glass-ceramic with natural crystalline analogues for immobilizing the calcined high-level nuclear waste at the Idaho Chemical Processing Plant International Nuclear Information System (INIS) Raman, S. 1993-12-01 The additives Si, Al, MgO, P 2 O 5 were mechanically blended with fluorinelsodium calcine in varying proportions. The batches were vacuum sealed in stainless steel canisters and hot isostatically pressed at 20,000 PSI and 1000 C for 4 hours. The resulting suite of glass-ceramic waste forms parallels the natural rocks in microstructural and compositional heterogeneity. Several crystalline phases ar analogous in composition and structure to naturally occurring minerals. Additional crystalline phases are zirconia and Ca-Mg borate. The glasses are enriched in silica and alumina. Approximately 7% calcine elements occur dissolved in this glass and the total glass content in the waste forms averages 20 wt%. The remainder of the calcine elements are partitioned into crystalline phases at 75 wt% calcine waste loading. The waste forms were tested for chemical durability in accordance with the MCC1-test procedure. The leach rates are a function of the relative proportions of additives and calcine, which in turn influence the composition and abundances of the glass and crystalline phases. The DOE leach rate criterion of less than 1 g/m 2 -day is met by all the elements B, Cs and Na are increased by lowering the melt viscosity. This is related to increased crystallization or devitrification with increases in MgO addition. This exploratory work has shown that the increases in waste loading occur by preferred partitioning of the calcine components among crystalline and glass phases. The determination of optimum processing parameters in the form of additive concentration levels, homogeneous blending among the components, and pressure-temperature stabilities of phases must be continued to eliminate undesirable effects of chemical composition, microstructure and glass devitrification 14. Influence of heat treatment on microstructure and tensile behavior of a hot isostatically pressed nickel-based superalloy Energy Technology Data Exchange (ETDEWEB) Qiu, Chunlei, E-mail: [email protected] [School of Metallurgy and Materials, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Wu, Xinhua; Mei, Junfa [School of Metallurgy and Materials, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Andrews, Paul; Voice, Wayne [Rolls-Royce Plc, Derby DE24 8BJ (United Kingdom) 2013-11-25 Highlights: •Post-HIP heat treatment led to refined microstructure and improved tensile properties. •Deformation occurred mainly by forming stacking faults in γ′ at RT and elevated temperature. •Net-shape HIPed RR1000 failed in a transgranular fracture mode. -- Abstract: A nickel-based superalloy powder RR1000 has been hot isostatically pressed (HIPed) and heat treated to produce different microstructures. Microstructures were investigated using a scanning electron microscope (SEM). Tensile testing was performed at room temperature and 700 °C and the deformed samples were examined using SEM and transmission electron microscope (TEM). It was found that in the as-HIPed condition the microstructure consisted of coarse and irregular-shaped primary and secondary γ′ together with a low volume fraction of fine γ′ (<50 nm in diameter). Solution treatment below the γ′ solvus followed by air cooling resulted in the formation of finer cuboidal secondary γ′ (350–750 nm) and medium-sized spherical tertiary γ′ (100–200 nm). This led to an improvement of both the 0.2% yield strength and ultimate tensile strength. Ageing of the solution-treated or of the as-HIPed samples at 760 °C resulted in the precipitation of a high population of fine γ′ (around 50 nm) which further increased the strength. Within the resolution limit of the current TEM analysis, deformation at room temperature seemed to occur mainly by dislocations cutting through secondary γ′ and very fine γ′, accompanied by the formation of stacking faults within these precipitates; most of the medium-sized tertiary γ′ precipitates in solution-treated and aged samples were not cut through but were surrounded by dislocations. Deformation at 700 °C happened by dislocations cutting through γ′ precipitates and γ matrix, leading to the formation of extended stacking faults across both γ and γ′. It is suggested that the optimum treatment of the current powder superalloy is to 15. Influence of heat treatment on microstructure and tensile behavior of a hot isostatically pressed nickel-based superalloy International Nuclear Information System (INIS) Qiu, Chunlei; Wu, Xinhua; Mei, Junfa; Andrews, Paul; Voice, Wayne 2013-01-01 Highlights: •Post-HIP heat treatment led to refined microstructure and improved tensile properties. •Deformation occurred mainly by forming stacking faults in γ′ at RT and elevated temperature. •Net-shape HIPed RR1000 failed in a transgranular fracture mode. -- Abstract: A nickel-based superalloy powder RR1000 has been hot isostatically pressed (HIPed) and heat treated to produce different microstructures. Microstructures were investigated using a scanning electron microscope (SEM). Tensile testing was performed at room temperature and 700 °C and the deformed samples were examined using SEM and transmission electron microscope (TEM). It was found that in the as-HIPed condition the microstructure consisted of coarse and irregular-shaped primary and secondary γ′ together with a low volume fraction of fine γ′ (<50 nm in diameter). Solution treatment below the γ′ solvus followed by air cooling resulted in the formation of finer cuboidal secondary γ′ (350–750 nm) and medium-sized spherical tertiary γ′ (100–200 nm). This led to an improvement of both the 0.2% yield strength and ultimate tensile strength. Ageing of the solution-treated or of the as-HIPed samples at 760 °C resulted in the precipitation of a high population of fine γ′ (around 50 nm) which further increased the strength. Within the resolution limit of the current TEM analysis, deformation at room temperature seemed to occur mainly by dislocations cutting through secondary γ′ and very fine γ′, accompanied by the formation of stacking faults within these precipitates; most of the medium-sized tertiary γ′ precipitates in solution-treated and aged samples were not cut through but were surrounded by dislocations. Deformation at 700 °C happened by dislocations cutting through γ′ precipitates and γ matrix, leading to the formation of extended stacking faults across both γ and γ′. It is suggested that the optimum treatment of the current powder superalloy is to 16. Effect of standard heat treatment on the microstructure and mechanical properties of hot isostatically pressed superalloy inconel 718 International Nuclear Information System (INIS) Rao, G. Appa; Kumar, Mahendra; Srinivas, M.; Sarma, D.S. 2003-01-01 Ni-Fe base superalloy, Inconel 718, was processed through powder metallurgy (P/M) hot isostatic pressing (HIP) route. In order to balance the strength and ductility, the HIPed material was given the standard heat treatment, viz. solution treatment at 980 deg. C for 1 h/water quenched (WQ) to room temperature and a two-step ageing treatment consisting of 720 deg. C for 8 h/furnace cooling (FC) at 55 deg. C h -1 to 620 deg. C and holding at 620 deg. C for 8 h before air cooling (AC) to room temperature. Optical microscopy and scanning electron microscopy (SEM) studies on the heat treated alloy have shown a homogeneous microstructure with fine grain size (25 μm) along with the presence of prior particle boundary (PPB) networks. Transmission electron microscopy (TEM) on the heat treated material has revealed the presence of oxides, MC carbides and δ-precipitates at the grain boundaries and a uniform precipitation of fine γ'' and γ' strengthening phases in the matrix. Tensile and stress rupture tests were performed on the heat treated material. While the yield strength (YS) and ultimate tensile strength (UTS) of the HIPed and heat treated alloy at room temperature and 650 deg. C were comparable to those of conventionally processed wrought IN 718, its ductility was lower. The stress rupture life of the HIPed alloy improved marginally due to heat treatment and met the minimum specification requirement of life hours but the rupture ductility was found to be inferior to that of the wrought material. The fractography of the failed samples has revealed the transgranular ductile mode of fracture in the as-solution treated alloy, while intergranular mode of failure with the decohesion of PPBs occurred more predominantly in the aged condition. This change of fracture mode with ageing treatment shows the ductility dependence on the relative strength of the matrix and PPBs. The TEM studies on the deformed alloy have revealed that the brittle oxides and carbides at the prior 17. Effect of heat treatment and hot isostatic pressing on the microstructure and mechanical properties of Inconel 625 alloy processed by laser powder bed fusion Energy Technology Data Exchange (ETDEWEB) Kreitcberg, Alena, E-mail: [email protected] [École de technologie supérieure, 110 Notre-Dame Street West, Montreal, Quebec H3C 1K3 Canada (Canada); Brailovski, Vladimir, E-mail: [email protected] [École de technologie supérieure, 110 Notre-Dame Street West, Montreal, Quebec H3C 1K3 Canada (Canada); Turenne, Sylvain, E-mail: [email protected] [École Polytechnique de Montréal, 2900 boul. Édouard-Montpetit, Montreal, Quebec H3T 1J4 Canada (Canada) 2017-03-24 The effect of different heat treatments and hot isostatic pressing on the microstructure and mechanical properties of laser powder bed fusion IN625 alloy was studied. The heat treatments were: stress relief annealing, recrystallization annealing and low-temperature solution treatment. The resulting microstructure and crystallographic textures were studied using optical and scanning electron microscopy. The mechanical properties of the as-built and post-treated IN625 alloy were obtained after tensile testing at room temperature and at 760 °C (1400 °F), and compared to those of an annealed wrought alloy of the same composition. 18. A novel Fe–Cr–Nb matrix composite containing the TiB_2 neutron absorber synthesized by mechanical alloying and final hot isostatic pressing (HIP) in the Ti-tubing International Nuclear Information System (INIS) Litwa, Przemysław; Perkowski, Krzysztof; Zasada, Dariusz; Kobus, Izabela; Konopka, Gustaw; Czujko, Tomasz; Varin, Robert A. 2016-01-01 The Fe–Cr–Ti-Nb elemental powders were mechanically alloyed/ball milled with TiB_2 and a small quantity of Y_2O_3 ceramic to synthesize a novel Fe-based alloy-ceramic powder composite that could be processed by hot isostatic pressing (HIP) for a perceived potential application as a neutron absorber in nuclear reactors. After ball milling for the 30–80 h duration relatively uniform powders with micrometric sizes were produced. With increasing milling time a fraction of TiB_2 particles became covered with the much softer Fe-based alloy which resulted in the formation of a characteristic “core-mantel” structure. For the final HIP-ing process the mechanically alloyed powders were initially uniaxially pressed into rod-shaped compacts and then cold isostatically pressed (CIP-ed). Subsequently, the rod-shaped compacts were placed in the Ti-tubing and subjected to hot isostatic pressing (HIP) at 1150 °C/200 MPa pressure. The HIP-ing process resulted in the formation of the near-Ti and intermediate diffusional layers in the microstructure of HIP-ed samples which formed in accord with the Fe-Ti binary phase diagram. Those layers contain the phases such as α-Ti (HCP), the FeTi intermetallic and their hypo-eutectoid mixtures. In addition, needle-like particles were formed in both layers in accord with the Ti-B binary phase diagram. Nanohardness testing, using a Berkovich type diamond tip, shows that the nanohardness in the intermediate layer areas, corresponding to the composition of the hypo-eutectoid mixture of Ti-FeTi, equals 980.0 (±27.1) HV and correspondingly 1176.9 (±47.6) HV for the FeTi phase. The nanohardness in the sample's center in the areas with the fine mixture of Fe-based alloy and small TiB_2 particles equals 1048.3 (±201.8) HV. The average microhardness of samples HIP-ed from powders milled for 30 and 80 h is 588 HV and 733 HV, respectively. - Highlights: • A Fe–Cr–Nb-based composite with TiB_2 neutron absorbing ceramic was mechanically 19. Radiation polymerized hot melt pressure sensitive adhesives International Nuclear Information System (INIS) Pastor, S.D.; Skoultchi, M.M. 1977-01-01 Hot melt pressure sensitive adhesive compositions formed by copolymerizing at least one 3-(chlorinated aryloxy)-2-hydroxypropyl ester of an alpha, beta unsaturated carboxylic acid with acrylate based copolymerizable monomers, are described. The resultant ethylenically saturated prepolymer is heated to a temperature sufficient to render it fluid and flowable. This composition is coated onto a substrate and exposed to ultraviolet radiation 20. Effects of internal gas pressure and microstructure on the mechanisms of hot-pressing and swelling in ceramics. Progress report, June 1, 1976--March 31, 1977 International Nuclear Information System (INIS) Solomon, A.A. 1977-02-01 The low temperature isostatic pressurization system has been completed, operated successfully and calibrated. The new high temperature TD tungsten vessel and MoSi 2 element furnace system has also been designed and is presently under construction. Porous CoO single crystals have been grown using a ''skull melting'' process. Automated quantitative microscopy techniques are being developed using the KONTRON system to examine porosity evaluation during hot-pressing and sintering. Initial sintering experiments under variable isostatic pressures from 100 μm Hg to 2000 psi reveal no significant effect of ambient pressure. Nor were differences observed in sintering kinetics when either Helium or Argon were used as the pressurizing gas. Swelling experiments, conducted by reducing the ambient pressure after pore closure, revealed dramatic changes in density. The densification rates also appeared to depend on history, suggesting that mechanical deformation may play a dominant role in hot-pressing, at least during transients 1. Influence of Powder Surface Contamination in the Ni-Based Superalloy Alloy718 Fabricated by Selective Laser Melting and Hot Isostatic Pressing Directory of Open Access Journals (Sweden) Yen-Ling Kuo 2017-09-01 Full Text Available The aim of this study was to gain a deep understanding of the microstructure-mechanical relationship between solid-state sintering and full-melting processes. The IN718 superalloy was fabricated by hot isostatic pressing (HIP and selective laser melting (SLM. Continuous precipitates were clearly localized along the prior particle boundary (PPB in the HIP materials, while SLM materials showed a microstructure free of PPB. The mechanical properties of specimens that underwent SLM + solution treatment and aging were comparable to those of conventional wrought specimens both at room temperature and 650 °C. However, a drop was observed in the ductility of HIP material at 650 °C. The brittle particles along the PPB were found to affect the HIP materials’ creep life and ductility during solid-state sintering. 2. Tensile ductility of an AlCoCrFeNi multi-phase high-entropy alloy through hot isostatic pressing (HIP) and homogenization Energy Technology Data Exchange (ETDEWEB) Tang, Zhi, E-mail: [email protected] [Department of Materials Science and Engineering, The University of Tennessee, Knoxville, TN 37996 (United States); Department of Materials Science and Engineering, Virginia Tech, Blacksburg, VA 24061 (United States); Senkov, Oleg N. [Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, OH 45433 (United States); Parish, Chad M. [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Zhang, Chuan; Zhang, Fan [CompuTherm LLC, 437 S. Yellowstone Dr., Suite 217, Madison, WI 53719 (United States); Santodonato, Louis J. [Department of Materials Science and Engineering, The University of Tennessee, Knoxville, TN 37996 (United States); Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Wang, Gongyao [Department of Materials Science and Engineering, The University of Tennessee, Knoxville, TN 37996 (United States); Zhao, Guangfeng; Yang, Fuqian [Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506 (United States); Liaw, Peter K., E-mail: [email protected] [Department of Materials Science and Engineering, The University of Tennessee, Knoxville, TN 37996 (United States) 2015-10-28 The microstructure and phase composition of an AlCoCrFeNi high-entropy alloy (HEA) were studied in as-cast (AlCoCrFeNi-AC, AC represents as-cast) and homogenized (AlCoCrFeNi-HP, HP signifies hot isostatic pressed and homogenized) conditions. The AlCoCrFeNi-AC ally has a dendritric structure in the consisting primarily of a nano-lamellar mixture of A2 (disordered body-centered-cubic (BCC)) and B2 (ordered BCC) phases, formed by an eutectic reaction. The homogenization heat treatment, consisting of hot isostatic pressed for 1 h at 1100 °C, 207 MPa and annealing at 1150 °C for 50 h, resulted in an increase in the volume fraction of the A1 phase and formation of a Sigma (σ) phase. Tensile properties in as-cast and homogenized conditions are reported at 700 °C. The ultimate tensile strength was virtually unaffected by heat treatment, and was 396±4 MPa at 700 °C. However, homogenization produced a noticeable increase in ductility. The AlCoCrFeNi-AC alloy showed a tensile elongation of only 1.0%, while after the heat-treatment, the elongation of AlCoCrFeNi-HP was 11.7%. Thermodynamic modeling of non-equilibrium and equilibrium phase diagrams for the AlCoCrFeNi HEA gave good agreement with the experimental observations of the phase contents in the AlCoCrFeNi-AC and AlCoCrFeNi-HP. The reasons for the improvement of ductility after the heat treatment and the crack initiation subjected to tensile loading were discussed. 3. The effect of pre-treatment parameters on the quality of glass-ceramic wasteforms for plutonium immobilisation, consolidated by hot isostatic pressing Energy Technology Data Exchange (ETDEWEB) Thornber, Stephanie M.; Heath, Paul G. [Immobilisation Science Laboratory, Department of Materials Science & Engineering, The University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD (United Kingdom); Da Costa, Gabriel P. [Immobilisation Science Laboratory, Department of Materials Science & Engineering, The University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD (United Kingdom); Department of Chemical Engineering & Petroleum Engineering, Universidade Federal Fluminense, Rua Passo da Patria 156, CEP 24210-240, Niteroi, RJ (Brazil); Stennett, Martin C. [Immobilisation Science Laboratory, Department of Materials Science & Engineering, The University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD (United Kingdom); Hyatt, Neil C., E-mail: [email protected] [Immobilisation Science Laboratory, Department of Materials Science & Engineering, The University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD (United Kingdom) 2017-03-15 Glass-ceramics with high glass fractions (70 wt%) were fabricated in stainless steel canisters by hot isostatic pressing (HIP), at laboratory scale. High (600 °C) and low (300 °C) temperature pre-treatments were investigated to reduce the canister evacuation time and to understand the effect on the phase assemblage and microstructure of the hot isostatically pressed product. Characterisation of the HIPed materials was performed using scanning electron microscopy (SEM), coupled with energy dispersive X-ray analysis (EDX) and powder X-ray diffraction (XRD). This analysis showed the microstructure and phase assemblage was independent of the variation in pre-treatment parameters. It was demonstrated that a high temperature pre-treatment of batch reagents, prior to the HIP cycle, is beneficial when using oxide precursors, in order to remove volatiles and achieve high quality dense materials. Sample throughput can be increased significantly by utilising a high temperature ex-situ calcination prior to the HIP cycle. Investigation of glass-ceramic wasteform processing utilising a glass frit precursor, produced a phase assemblage and microstructure comparable to that obtained using oxide precursors. The use of a glass frit precursor should allow optimised throughput of waste packages in a production facility, avoiding the need for a calcination pre-treatment required to remove volatiles from oxide precursors. - Highlights: • Optimisation of pre-treatment parameters for HIP glass-ceramics was investigated. • Entrained porosity was minimised by ex-situ bake-out of oxide precursors at 600 °C. • Phase assemblage and microstructure proved independent of bake-out parameters. • Use of glass-frit precursor further improved process s throughput and simplification. 4. The effect of pre-treatment parameters on the quality of glass-ceramic wasteforms for plutonium immobilisation, consolidated by hot isostatic pressing International Nuclear Information System (INIS) Thornber, Stephanie M.; Heath, Paul G.; Da Costa, Gabriel P.; Stennett, Martin C.; Hyatt, Neil C. 2017-01-01 Glass-ceramics with high glass fractions (70 wt%) were fabricated in stainless steel canisters by hot isostatic pressing (HIP), at laboratory scale. High (600 °C) and low (300 °C) temperature pre-treatments were investigated to reduce the canister evacuation time and to understand the effect on the phase assemblage and microstructure of the hot isostatically pressed product. Characterisation of the HIPed materials was performed using scanning electron microscopy (SEM), coupled with energy dispersive X-ray analysis (EDX) and powder X-ray diffraction (XRD). This analysis showed the microstructure and phase assemblage was independent of the variation in pre-treatment parameters. It was demonstrated that a high temperature pre-treatment of batch reagents, prior to the HIP cycle, is beneficial when using oxide precursors, in order to remove volatiles and achieve high quality dense materials. Sample throughput can be increased significantly by utilising a high temperature ex-situ calcination prior to the HIP cycle. Investigation of glass-ceramic wasteform processing utilising a glass frit precursor, produced a phase assemblage and microstructure comparable to that obtained using oxide precursors. The use of a glass frit precursor should allow optimised throughput of waste packages in a production facility, avoiding the need for a calcination pre-treatment required to remove volatiles from oxide precursors. - Highlights: • Optimisation of pre-treatment parameters for HIP glass-ceramics was investigated. • Entrained porosity was minimised by ex-situ bake-out of oxide precursors at 600 °C. • Phase assemblage and microstructure proved independent of bake-out parameters. • Use of glass-frit precursor further improved process s throughput and simplification. 5. Microwave Combustion and Sintering Without Isostatic Pressure. Topical Report August 1, 1995 - October 30, 1996 International Nuclear Information System (INIS) Ebadian, M.A.; Monroe, N.D.H. 1998-01-01 This investigation involves a study of the influence of key processing parameters on the heating of materials using microwave energy. Selective and localized heating characteristics of microwaves will be utilized in the sintering of ceramics without hydrostatic pressure. In addition, combustion synthesis will be studied for the production of powders, carbides, and nitrides by combining two or more solids or a solid and a gas to form new materials. The insight gained from the interaction of microwaves with various materials will be utilized in the mobilization and subsequent redeposition of uranium 6. Potential of high isostatic pressure and pulsed electric fields for the processing of potato and pea proteins:structural and techno-functional characterization in model solutions and plant tissue OpenAIRE Baier, Anne Kathrin 2016-01-01 The aim of this thesis was to evaluate the potential of high isostatic pressure and pulsed electric fields for the production of high quality plant proteins. Induced changes in protein solutions and plant tissue of potato and pea were analyzed by means of structural and techno-functional characterization as well as by investigation of diffusion and extractions procedures. The application of high isostatic pressure provides a gentle alternative to conventional heat preservation. Especially ... 7. Enhancement in the microstructure and neutron shielding efficiency of sandwich type of 6061Al–B4C composite material via hot isostatic pressing International Nuclear Information System (INIS) Park, Jin-Ju; Hong, Sung-Mo; Lee, Min-Ku; Rhee, Chang-Kyu; Rhee, Won-Hyuk 2015-01-01 Highlights: • 6061Al–B 4 C neutron shielding composites are fabricated by sintering and HIP. • HIP process improves the wettability of B 4 C particles into 6061Al matrix. • Neutron attenuation performance can be enhanced by application of HIP process. - Abstract: Sandwich type of 6061Al–B 4 C composite plates, which are used as a thermal neutron absorber for spent nuclear fuel pool storage rack, were fabricated using two different consolidation ways as sintering and hot isostatic pressing (HIP) processes and their thermal neutron shielding efficiency was investigated as a function of B 4 C concentration ranging from 0 to 40 wt.%. For this purpose, two respective inner core compaction parts of sintered and HIPped neutron absorbing composite materials were first produced and then cladded them between two outer plates by HIP process. The application of HIP process provided not only a lead of excellent interfacial adhesion due to the improved wettability but also an enhancement of thermal neutron shielding efficiency owing to the more uniform dispersion of B 4 C particles 8. Development of manufacturing technology of radial plate in superconducting coil for fusion reactor by diffusion bonding by Hot Isostatic Pressing (HIP) International Nuclear Information System (INIS) Takano, Katsutoshi; Koizumi, Norikiyo; Masuo, Hiroshi; Natsume, Yoshihisa 2014-01-01 The radial plates (RPs), which is used in Toroidal field (TF) coil in ITER, are quite large, such as 13 m tall and 9 m wide, but thin, such as 10 cm thick, and are made of stainless steel. Even though they are very large structures, they require very high manufacturing tolerances and high mechanical strength at 4 K. The similar requirements will be required in the next generation fusion reactor. Therefore, the authors intend to develop efficient manufacturing methods in parallel with ITER TF coil RP manufacture. The authors therefore performed trial manufacture of the RP segments using a diffusion bonding method, namely Hot Isostatic Pressing (HIP). As a result of trials, it was clarified that even when HIPping is applied, the mechanical characteristic of base metal is not deteriorated. The machining period can be reduced by about 1/3 compared with the traditional manufacturing method. On the other hand, mechanical strength at 4 K is degraded due to weak bonding, that is no grain growth through joint, by HIPping. However, additional test indicates promising possibility of much better joint by higher temperature and joint surface treated HIPpings. These results justified that RP segment manufacturing is not only possible, but it is a technically valid manufacturing method that satisfies all requirements. (author) 9. Selective Electron Beam Manufacturing of Ti-6Al-4V Strips: Effect of Build Orientation, Columnar Grain Orientation, and Hot Isostatic Pressing on Tensile Properties Science.gov (United States) Wang, J.; Tang, H. P.; Yang, K.; Liu, N.; Jia, L.; Qian, M. 2018-03-01 Many novel designs for additive manufacturing (AM) contain thin-walled (≤ 3 mm) sections in different orientations. Selective electron beam melting (SEBM) is particularly suited to AM of such thin-walled titanium components because of its high preheating temperature and high vacuum. However, experimental data on SEBM of Ti-6Al-4V thin sections remains scarce because of the difficulty and high cost of producing long, thin and smooth strip tensile specimens (see Fig. 1). In this study, 80 SEBM Ti-6Al-4V strips (180 mm long, 42 mm wide, 3 mm thick) were built both vertically (V-strips) and horizontally (H-strips). Their density, microstructure and tensile properties were investigated. The V-strips showed clearly higher tensile strengths but lower elongation than the H-strips. Hot isostatic pressing (HIP) produced the same lamellar α-β microstructures in terms of the average α-lath thickness in both types of strips. The retained prior-β columnar grain boundaries after HIP showed no measurable influence on the tensile properties, irrespective of their length and orientation, because of the formation of randomly distributed fine α-laths.[Figure not available: see fulltext. 10. Effects of long-time elevated temperature exposures on hot-isostatically-pressed power-metallurgy Udimet 700 alloys with reduced cobalt contents Science.gov (United States) Hart, F. H. 1984-01-01 Because almost the entire U.S. consumption of cobalt depends on imports, this metal has been designated "strategic'. The role and effectiveness of cobalt is being evaluated in commercial nickel-base superalloys. Udiment 700 type alloys in which the cobalt content was reduced from the normal 17% down to 12.7%, 8.5%, 4.3%, and 0% were prepared by standard powder metallurgy techniques and hot isostatically pressed into billets. Mechanical testing and microstructural investigations were performed. The mechanical properties of alloys with reduced cobalt contents which were heat-treated identically were equal or better than those of the standard alloy, except that creep rates tended to increase as cobalt was reduced. The effects of long time exposures at 760 C on mechanical properties and at 760 C and 845 C on microstructures were determined. Decreased tensile properties and shorter rupture lives with increased creep rates were observed in alloy modifications. The exposures caused gamma prime particle coarsening and formation of sigma phase in the alloys with higher cobalt contents. Exposure at 845 C also reduced the amount of MC carbides. 11. A novel Fe–Cr–Nb matrix composite containing the TiB{sub 2} neutron absorber synthesized by mechanical alloying and final hot isostatic pressing (HIP) in the Ti-tubing Energy Technology Data Exchange (ETDEWEB) Litwa, Przemysław [Department of Advanced Materials and Technologies, Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland); Perkowski, Krzysztof [Department of Nanotechnology, Institute of Ceramics and Building Materials, Postępu 9, 02-676 Warsaw (Poland); Zasada, Dariusz [Department of Advanced Materials and Technologies, Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland); Kobus, Izabela; Konopka, Gustaw [Department of Nanotechnology, Institute of Ceramics and Building Materials, Postępu 9, 02-676 Warsaw (Poland); Czujko, Tomasz [Department of Advanced Materials and Technologies, Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland); Varin, Robert A., E-mail: [email protected] [Department of Mechanical and Mechatronics Engineering, University of Waterloo, 200 University Ave., Waterloo, ON N2L 3G1 (Canada) 2016-07-25 The Fe–Cr–Ti-Nb elemental powders were mechanically alloyed/ball milled with TiB{sub 2} and a small quantity of Y{sub 2}O{sub 3} ceramic to synthesize a novel Fe-based alloy-ceramic powder composite that could be processed by hot isostatic pressing (HIP) for a perceived potential application as a neutron absorber in nuclear reactors. After ball milling for the 30–80 h duration relatively uniform powders with micrometric sizes were produced. With increasing milling time a fraction of TiB{sub 2} particles became covered with the much softer Fe-based alloy which resulted in the formation of a characteristic “core-mantel” structure. For the final HIP-ing process the mechanically alloyed powders were initially uniaxially pressed into rod-shaped compacts and then cold isostatically pressed (CIP-ed). Subsequently, the rod-shaped compacts were placed in the Ti-tubing and subjected to hot isostatic pressing (HIP) at 1150 °C/200 MPa pressure. The HIP-ing process resulted in the formation of the near-Ti and intermediate diffusional layers in the microstructure of HIP-ed samples which formed in accord with the Fe-Ti binary phase diagram. Those layers contain the phases such as α-Ti (HCP), the FeTi intermetallic and their hypo-eutectoid mixtures. In addition, needle-like particles were formed in both layers in accord with the Ti-B binary phase diagram. Nanohardness testing, using a Berkovich type diamond tip, shows that the nanohardness in the intermediate layer areas, corresponding to the composition of the hypo-eutectoid mixture of Ti-FeTi, equals 980.0 (±27.1) HV and correspondingly 1176.9 (±47.6) HV for the FeTi phase. The nanohardness in the sample's center in the areas with the fine mixture of Fe-based alloy and small TiB{sub 2} particles equals 1048.3 (±201.8) HV. The average microhardness of samples HIP-ed from powders milled for 30 and 80 h is 588 HV and 733 HV, respectively. - Highlights: • A Fe–Cr–Nb-based composite with TiB{sub 2} neutron 12. Sintering of ZrC by hot isostatic pressing (HIP) and spark plasma sintering (SPS). Effect of impurities International Nuclear Information System (INIS) Allemand, Alexandre; Le Flem - Dormeval, Marion; Guillard, Francois 2005-01-01 Carbides are generally used as structural materials for high temperature applications. Particularly, ZrC because of low activation, neutronic transparency, cubic structure (isotropic behaviour) and good thermal conductivity, is one of the candidates under consideration for structural materials in the core of new high temperature nuclear reactors (Generation IV). Just a few studies about densification of monolithic ZrC exist. They mainly involve natural sintering or hot pressing at high temperature (until 2700 deg. C). Unfortunately those processes induce grain growth and do not lead to fully densified ZrC. The aim of this study is to compare the characteristics and the properties of ZrC sintered by HIP and by SPS. Fully dense ZrC can be reached either by HIP or by SPS, grain size being more or less controlled. Microstructural observations and mechanical testing of several ZrC grades shows that powder impurities play an important role in the quality of the grain boundaries and consequently in the mechanical properties. In particular, the porosity falls from 17% to 3 % just by reducing the free carbon content in starting ZrC powder. The densification process of dense monolithic ZrC was improved by combining a HIP at 1600 deg. C (titanium canning) followed by a post-HIP at 1900 deg. C (no canning required). Four-point bending tests are in progress to confirm the improvement of fracture strength. (authors) 13. Production of an impermeable composite of irradiated graphite and glass by hot isostatic pressing as a long term leach resistant waste form Energy Technology Data Exchange (ETDEWEB) Fachinger, Johannes; Muller, Walter [FNAG ZU Hanau, Hanau (Germany); Marsat, Eric [FNAG SAS Le Pont de Claix (France); Grosse, Karl-Heinz; Seemann, Richard [ALD Hanau (Germany); Scales, Charlie; Easton, Michael Mark [NNL, Workington (United Kingdom); Anthony Banford [NNL, Warrington (United Kingdom); University of Manchester, Manchester (United Kingdom) 2013-07-01 negligible porosity and a water impermeable structure. Structural analysis shows that the glass in the composite has replaced the pores in the graphite structure. The typical pore volume of a graphite material is in the range of 20 vol.%. Therefore no volume increase will occur in comparison with the former graphite material. This IGM material will allow the encapsulation of graphite with package densities larger than 1.5 ton per cubic meter. Therefore a huge volume saving can be achieved by such an alternative encapsulation method. Disposal performance is also enhanced since little or no leaching of radionuclides is observed due to the impermeability of the material NNL and FNAG have proved that IGM can be produced by hot isostatic pressing (HIP) which has several advantages for radioactive materials over the HVP process. - The sealed HIP container avoids the release of any radionuclides. - The outside of the waste package is not contaminated. - The HIP process time is shorter than the HVP process time. The isostatic press avoids anisotropic density distributions. - Simple filling of the HIP container has advantages over the filling of an axial die. (authors) 14. Production of an impermeable composite of irradiated graphite and glass by hot isostatic pressing as a long term leach resistant waste form International Nuclear Information System (INIS) Fachinger, Johannes; Muller, Walter; Marsat, Eric; Grosse, Karl-Heinz; Seemann, Richard; Scales, Charlie; Easton, Michael Mark; Anthony Banford 2013-01-01 negligible porosity and a water impermeable structure. Structural analysis shows that the glass in the composite has replaced the pores in the graphite structure. The typical pore volume of a graphite material is in the range of 20 vol.%. Therefore no volume increase will occur in comparison with the former graphite material. This IGM material will allow the encapsulation of graphite with package densities larger than 1.5 ton per cubic meter. Therefore a huge volume saving can be achieved by such an alternative encapsulation method. Disposal performance is also enhanced since little or no leaching of radionuclides is observed due to the impermeability of the material NNL and FNAG have proved that IGM can be produced by hot isostatic pressing (HIP) which has several advantages for radioactive materials over the HVP process. - The sealed HIP container avoids the release of any radionuclides. - The outside of the waste package is not contaminated. - The HIP process time is shorter than the HVP process time. The isostatic press avoids anisotropic density distributions. - Simple filling of the HIP container has advantages over the filling of an axial die. (authors) 15. Growth kinetics and microstructural evolution during hot isostatic pressing of U-10 wt.% Mo monolithic fuel plate in AA6061 cladding with Zr diffusion barrier International Nuclear Information System (INIS) Park, Y.; Yoo, J.; Huang, K.; Keiser, D.D.; Jue, J.F.; Rabin, B.; Moore, G.; Sohn, Y.H. 2014-01-01 Phase constituents and microstructure changes in RERTR fuel plate assemblies as functions of temperature and duration of hot-isostatic pressing (HIP) during fabrication were examined. The HIP process was carried out as functions of temperature (520, 540, 560 and 580 °C for 90 min) and time (45–345 min at 560 °C) to bond 6061 Al-alloy to the Zr diffusion barrier that had been co-rolled with U-10 wt.% Mo (U10Mo) fuel monolith prior to the HIP process. Scanning and transmission electron microscopies were employed to examine the phase constituents, microstructure and layer thickness of interaction products from interdiffusion. At the interface between the U10Mo and Zr, following the co-rolling, the UZr 2 phase was observed to develop adjacent to Zr, and the α-U phase was found between the UZr 2 and U10Mo, while the Mo 2 Zr was found as precipitates mostly within the α-U phase. The phase constituents and thickness of the interaction layer at the U10Mo-Zr interface remained unchanged regardless of HIP processing variation. Observable growth due to HIP was only observed for the (Al,Si) 3 Zr phase found at the Zr/AA6061 interface, however, with a large activation energy of 457 ± 28 kJ/mole. Thus, HIP can be carried to improve the adhesion quality of fuel plate without concern for the excessive growth of the interaction layer, particularly at the U10Mo-Zr interface with the α-U, Mo 2 Zr, and UZr 2 phases 16. Growth kinetics and microstructural evolution during hot isostatic pressing of U-10 wt.% Mo monolithic fuel plate in AA6061 cladding with Zr diffusion barrier Energy Technology Data Exchange (ETDEWEB) Park, Y.; Yoo, J.; Huang, K. [Advanced Materials Processing and Analysis Center, Department of Materials Science and Engineering, University of Central Florida, Orlando, FL 32816 (United States); Keiser, D.D.; Jue, J.F.; Rabin, B.; Moore, G. [Idaho National Laboratory, PO Box 1625, Idaho Falls, ID 83401 (United States); Sohn, Y.H., E-mail: [email protected] [Advanced Materials Processing and Analysis Center, Department of Materials Science and Engineering, University of Central Florida, Orlando, FL 32816 (United States) 2014-04-01 Phase constituents and microstructure changes in RERTR fuel plate assemblies as functions of temperature and duration of hot-isostatic pressing (HIP) during fabrication were examined. The HIP process was carried out as functions of temperature (520, 540, 560 and 580 °C for 90 min) and time (45–345 min at 560 °C) to bond 6061 Al-alloy to the Zr diffusion barrier that had been co-rolled with U-10 wt.% Mo (U10Mo) fuel monolith prior to the HIP process. Scanning and transmission electron microscopies were employed to examine the phase constituents, microstructure and layer thickness of interaction products from interdiffusion. At the interface between the U10Mo and Zr, following the co-rolling, the UZr{sub 2} phase was observed to develop adjacent to Zr, and the α-U phase was found between the UZr{sub 2} and U10Mo, while the Mo{sub 2}Zr was found as precipitates mostly within the α-U phase. The phase constituents and thickness of the interaction layer at the U10Mo-Zr interface remained unchanged regardless of HIP processing variation. Observable growth due to HIP was only observed for the (Al,Si){sub 3}Zr phase found at the Zr/AA6061 interface, however, with a large activation energy of 457 ± 28 kJ/mole. Thus, HIP can be carried to improve the adhesion quality of fuel plate without concern for the excessive growth of the interaction layer, particularly at the U10Mo-Zr interface with the α-U, Mo{sub 2}Zr, and UZr{sub 2} phases. 17. Growth kinetics and microstructural evolution during hot isostatic pressing of U-10 wt.% Mo monolithic fuel plate in AA6061 cladding with Zr diffusion barrier Science.gov (United States) Park, Y.; Yoo, J.; Huang, K.; Keiser, D. D.; Jue, J. F.; Rabin, B.; Moore, G.; Sohn, Y. H. 2014-04-01 Phase constituents and microstructure changes in RERTR fuel plate assemblies as functions of temperature and duration of hot-isostatic pressing (HIP) during fabrication were examined. The HIP process was carried out as functions of temperature (520, 540, 560 and 580 °C for 90 min) and time (45-345 min at 560 °C) to bond 6061 Al-alloy to the Zr diffusion barrier that had been co-rolled with U-10 wt.% Mo (U10Mo) fuel monolith prior to the HIP process. Scanning and transmission electron microscopies were employed to examine the phase constituents, microstructure and layer thickness of interaction products from interdiffusion. At the interface between the U10Mo and Zr, following the co-rolling, the UZr2 phase was observed to develop adjacent to Zr, and the α-U phase was found between the UZr2 and U10Mo, while the Mo2Zr was found as precipitates mostly within the α-U phase. The phase constituents and thickness of the interaction layer at the U10Mo-Zr interface remained unchanged regardless of HIP processing variation. Observable growth due to HIP was only observed for the (Al,Si)3Zr phase found at the Zr/AA6061 interface, however, with a large activation energy of 457 ± 28 kJ/mole. Thus, HIP can be carried to improve the adhesion quality of fuel plate without concern for the excessive growth of the interaction layer, particularly at the U10Mo-Zr interface with the α-U, Mo2Zr, and UZr2 phases. 18. The positive effect of hot isostatic pressing on improving the anisotropies of bending and impact properties in selective laser melted Ti-6Al-4V alloy International Nuclear Information System (INIS) Wu, Ming-Wei; Lai, Pang-Hsin 2016-01-01 Selective laser melting (SLM) is a versatile additive manufacturing process for fabricating solid or porous metallic materials with complicated three-dimensional shapes. SLM Ti alloys, particularly Ti-6Al-4V, and other alloys have been manufactured and analyzed in numerous studies. However, the high anisotropy of the microstructures and inconsistent mechanical properties of SLM materials have been extensively reported, and these disadvantages could prohibit its widespread use. To clarify how to alleviate the anisotropic behaviors of SLM materials, the main objective of this study was to evaluate the influences of hot isostatic pressing (HIP) on the microstructure, densification, bending strength, impact toughness, and fracture behavior of the as-built Ti-6Al-4V alloy. The results showed that the vertical and horizontal building directions obviously affect the bending and impact properties of as-built alloys. The transverse rupture strength (TRS) and impact energy of the horizontally-built alloy were respectively found to be 48% and 100% higher than those of the vertically-built one. In the vertically-built alloy, disc-shaped building defects, identified by X-ray computed tomography (CT) and microscopy, obviously reduce the effective load-bearing cross-section and deteriorate the bending and impact performances. After HIP at 1000 °C/150 MPa, the α′-martensite structure in the as-built alloy is transformed into an α+β lamellar one, and the disc-shaped building defects are evidently eliminated. As a result, the impact energies of as-built vertical and horizontal specimens are improved by 28 J (560%) and 19 J (190%), respectively, and the TRS of the as-built vertical alloy is raised by 550 MPa (37%). Consequently, the discrepancies in TRS and impact energy between the HIPed vertical and horizontal specimens are merely 3% and 14%, respectively, and the anisotropic behaviors of the SLM Ti-6Al-4V alloy are thus substantially lessened. 19. Investigation of the Microstructure and Mechanical Properties of Copper-Graphite Composites Reinforced with Single-Crystal α-Al₂O₃ Fibres by Hot Isostatic Pressing. Science.gov (United States) Zhang, Guihang; Jiang, Xiaosong; Qiao, ChangJun; Shao, Zhenyi; Zhu, Degui; Zhu, Minhao; Valcarcel, Victor 2018-06-11 Single-crystal α-Al₂O₃ fibres can be utilized as a novel reinforcement in high-temperature composites owing to their high elastic modulus, chemical and thermal stability. Unlike non-oxide fibres and polycrystalline alumina fibres, high-temperature oxidation and polycrystalline particles boundary growth will not occur for single-crystal α-Al₂O₃ fibres. In this work, single-crystal α-Al₂O₃ whiskers and Al₂O₃ particles synergistic reinforced copper-graphite composites were fabricated by mechanical alloying and hot isostatic pressing techniques. The phase compositions, microstructures, and fracture morphologies of the composites were investigated using X-ray diffraction, a scanning electron microscope equipped with an X-ray energy-dispersive spectrometer (EDS), an electron probe microscopic analysis equipped with wavelength-dispersive spectrometer, and a transmission electron microscope equipped with EDS. The mechanical properties have been measured by a micro-hardness tester and electronic universal testing machine. The results show that the reinforcements were unevenly distributed in the matrix with the increase of their content and there were some micro-cracks located at the interface between the reinforcement and the matrix. With the increase of the Al₂O₃ whisker content, the compressive strength of the composites first increased and then decreased, while the hardness decreased. The fracture and strengthening mechanisms of the composite materials were explored on the basis of the structure and composition of the composites through the formation and function of the interface. The main strengthening mechanism in the composites was fine grain strengthening and solid solution strengthening. The fracture type of the composites was brittle fracture. 20. The positive effect of hot isostatic pressing on improving the anisotropies of bending and impact properties in selective laser melted Ti-6Al-4V alloy Energy Technology Data Exchange (ETDEWEB) Wu, Ming-Wei, E-mail: [email protected]; Lai, Pang-Hsin 2016-03-21 Selective laser melting (SLM) is a versatile additive manufacturing process for fabricating solid or porous metallic materials with complicated three-dimensional shapes. SLM Ti alloys, particularly Ti-6Al-4V, and other alloys have been manufactured and analyzed in numerous studies. However, the high anisotropy of the microstructures and inconsistent mechanical properties of SLM materials have been extensively reported, and these disadvantages could prohibit its widespread use. To clarify how to alleviate the anisotropic behaviors of SLM materials, the main objective of this study was to evaluate the influences of hot isostatic pressing (HIP) on the microstructure, densification, bending strength, impact toughness, and fracture behavior of the as-built Ti-6Al-4V alloy. The results showed that the vertical and horizontal building directions obviously affect the bending and impact properties of as-built alloys. The transverse rupture strength (TRS) and impact energy of the horizontally-built alloy were respectively found to be 48% and 100% higher than those of the vertically-built one. In the vertically-built alloy, disc-shaped building defects, identified by X-ray computed tomography (CT) and microscopy, obviously reduce the effective load-bearing cross-section and deteriorate the bending and impact performances. After HIP at 1000 °C/150 MPa, the α′-martensite structure in the as-built alloy is transformed into an α+β lamellar one, and the disc-shaped building defects are evidently eliminated. As a result, the impact energies of as-built vertical and horizontal specimens are improved by 28 J (560%) and 19 J (190%), respectively, and the TRS of the as-built vertical alloy is raised by 550 MPa (37%). Consequently, the discrepancies in TRS and impact energy between the HIPed vertical and horizontal specimens are merely 3% and 14%, respectively, and the anisotropic behaviors of the SLM Ti-6Al-4V alloy are thus substantially lessened. 1. Cold Isostatic-Pressured Silver Nanowire Electrodes for Flexible Organic Solar Cells via Room-Temperature Processes. Science.gov (United States) Seo, Ji Hoon; Hwang, Inchan; Um, Han-Don; Lee, Sojeong; Lee, Kangmin; Park, Jeonghwan; Shin, Hyeonoh; Kwon, Tae-Hyuk; Kang, Seok Ju; Seo, Kwanyong 2017-08-01 Transparent conducting electrodes (TCEs) are considered to be an essential structural component of flexible organic solar cells (FOSCs). Silver nanowire (AgNW) electrodes are widely used as TCEs owing to their excellent electrical and optical properties. The fabrication of AgNW electrodes has faced challenges in terms of forming large uniform interconnected networks so that high conductivity and reproducibility can be achieved. In this study, a simple method for creating an intimate contact between AgNWs that uses cold isostatic pressing (CIP) is demonstrated. This method increases the conductivity of the AgNW electrodes, which enables the fabrication of high-efficiency inverted FOSCs that have a power conversion efficiency of 8.75% on flexible polyethylene terephthalate with no short circuiting occurring as the CIP process minimizes the surface roughness of the AgNW electrode. This allows to achieve 100% manufacturing yield of FOSCs. Furthermore, these highly efficient FOSCs are proven to only be 2.4% less efficient even for an extreme bending radius of R ≈ 1.5 mm, compared with initial efficiency. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. 2. Bulging of pressure tubes at hot spots under LOCA conditions International Nuclear Information System (INIS) Manu, C.; Shewfelt, R.S.W.; Wright, A.C.D.; Aboud, R.; Lau, J.H.K.; Sanderson, D.B. 1996-01-01 During certain postulated loss-of-coolant accidents (LOCA) in a CANDU reactor, some fuel channels can become highly voided within a very short time. Although the pressure tubes are heated mainly by convection and thermal radiation during the LOCA transient, additional heat flow occurs through the bearing pads that are in contact with the pressure tribe. This contact can lead to local hot spots and associated thermal stresses in the pressure tube wall. The two factors that affects the behavior of the pressure tubes during LOCA conditions are the internal pressure and the local heating. Although the effect of internal pressure and of axially uniform temperature has been studied elsewhere, the effect of the local heating on the pressure tube behavior has not been modelled before. This paper shows that the bulging of a pressure tube at a hot spot is the result of the thermal stresses that are developed in a pressure tube during a LOCA transient. To isolate the local heating effect from the internal pressure, a series of single-effect experiments was performed. In these experiments, sections of a CANDU pressure tube were subjected to local heating only. The thermal profile and the local deformation were measured function of time. To quantify the effect of the thermal stresses on the bulging of pressure tubes at hot spots and to develop numerical tools that can predict such bulging, finite element analyses were performed rising the ABAQUS finite element computer code. Use of the measured thermal profiles in the ABAQUS finite element analysis, resulted in very good agreement between the predicted and measured displacements. (author) 3. Isostatic compression of buffer blocks. Middle scale International Nuclear Information System (INIS) Ritola, J.; Pyy, E. 2012-01-01 Manufacturing of buffer components using isostatic compression method has been studied in small scale in 2008 (Laaksonen 2010). These tests included manufacturing of buffer blocks using different bentonite materials and different compression pressures. Isostatic mould technology was also tested, along with different methods to fill the mould, such as vibration and partial vacuum, as well as a stepwise compression of the blocks. The development of manufacturing techniques has continued with small-scale (30 %) blocks (diameter 600 mm) in 2009. This was done in a separate project: Isostatic compression, manufacturing and testing of small scale (D = 600 mm) buffer blocks. The research on the isostatic compression method continued in 2010 in a project aimed to test and examine the isostatic manufacturing process of buffer blocks at 70 % scale (block diameter 1200 to 1300 mm), and the aim was to continue in 2011 with full-scale blocks (diameter 1700 mm). A total of nine bentonite blocks were manufactured at 70 % scale, of which four were ring-shaped and the rest were cylindrical. It is currently not possible to manufacture full-scale blocks, because there is no sufficiently large isostatic press available. However, such a compression unit is expected to be possible to use in the near future. The test results of bentonite blocks, produced with an isostatic pressing method at different presses and at different sizes, suggest that the technical characteristics, for example bulk density and strength values, are somewhat independent of the size of the block, and that the blocks have fairly homogenous characteristics. Water content and compression pressure are the two most important properties determining the characteristics of the compressed blocks. By adjusting these two properties it is fairly easy to produce blocks at a desired density. The commonly used compression pressure in the manufacturing of bentonite blocks is 100 MPa, which compresses bentonite to approximately 4. Isostatic compression of buffer blocks. Middle scale Energy Technology Data Exchange (ETDEWEB) Ritola, J.; Pyy, E. [VTT Technical Research Centre of Finland, Espoo (Finland) 2012-01-15 Manufacturing of buffer components using isostatic compression method has been studied in small scale in 2008 (Laaksonen 2010). These tests included manufacturing of buffer blocks using different bentonite materials and different compression pressures. Isostatic mould technology was also tested, along with different methods to fill the mould, such as vibration and partial vacuum, as well as a stepwise compression of the blocks. The development of manufacturing techniques has continued with small-scale (30 %) blocks (diameter 600 mm) in 2009. This was done in a separate project: Isostatic compression, manufacturing and testing of small scale (D = 600 mm) buffer blocks. The research on the isostatic compression method continued in 2010 in a project aimed to test and examine the isostatic manufacturing process of buffer blocks at 70 % scale (block diameter 1200 to 1300 mm), and the aim was to continue in 2011 with full-scale blocks (diameter 1700 mm). A total of nine bentonite blocks were manufactured at 70 % scale, of which four were ring-shaped and the rest were cylindrical. It is currently not possible to manufacture full-scale blocks, because there is no sufficiently large isostatic press available. However, such a compression unit is expected to be possible to use in the near future. The test results of bentonite blocks, produced with an isostatic pressing method at different presses and at different sizes, suggest that the technical characteristics, for example bulk density and strength values, are somewhat independent of the size of the block, and that the blocks have fairly homogenous characteristics. Water content and compression pressure are the two most important properties determining the characteristics of the compressed blocks. By adjusting these two properties it is fairly easy to produce blocks at a desired density. The commonly used compression pressure in the manufacturing of bentonite blocks is 100 MPa, which compresses bentonite to approximately 5. High isostatic pressure and thermal processing of açaí fruit (Euterpe oleracea Martius): Effect on pulp color and inactivation of peroxidase and polyphenol oxidase. Science.gov (United States) Jesus, Ana Laura Tibério de; Leite, Thiago Soares; Cristianini, Marcelo 2018-03-01 The present study evaluated the effect of high isostatic pressure (HIP) on the activity of peroxidase (POD) and polyphenol oxidase (PPO) from açaí. Açaí pulp was submitted to several combinations of pressure (400, 500, 600MPa), temperature (25 and 65°C) for 5 and 15min. The combined effect of HIP technology and high temperatures (690MPa by 2 and 5min at 80°C) was also investigated and compared to the conventional thermal treatment (85°C/1min). POD and PPO enzyme activity and instrumental color were examined after processing and after 24h of refrigerated storage. Results showed stability of POD for all pressures at 25°C, which proved to be heat-resistant and baro-resistant at 65°C. For PPO, the inactivation at 65°C was 71.7% for 600MPa after 15min. In general, the increase in temperature from 25°C to 65°C reduced the PPO relative activity with no changes in color. Although the thermal treatment and the HIP (690MPa) along with high temperature (80°C) reduced the PPO relative activity, and relevant darkening was observed in the processed samples. Thus, it can be concluded that POD is more baro-resistant than PPO in açaí pulp subjected to the same HIP processing conditions and processing at 600MPa/65°C for 5min may be an effective alternative for thermal pasteurization treatments. Copyright © 2017 Elsevier Ltd. All rights reserved. 6. Solubility of solid ferrocene in pressurized hot water Czech Academy of Sciences Publication Activity Database Karásek, Pavel; Hohnová, Barbora; Planeta, Josef; Roth, Michal 2010-01-01 Roč. 55, č. 8 (2010), s. 2866-2869 ISSN 0021-9568 R&D Projects: GA ČR GA203/07/0886; GA ČR GA203/08/1465; GA ČR GA203/08/1536 Institutional research plan: CEZ:AV0Z40310501 Keywords : pressurized hot water * ferrocene * solubility Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.089, year: 2010 7. Solubilities of oxygenated aromatic solids in pressurized hot water Czech Academy of Sciences Publication Activity Database Karásek, Pavel; Planeta, Josef; Roth, Michal 2009-01-01 Roč. 54, č. 5 (2009), s. 1457-1461 ISSN 0021-9568 R&D Projects: GA ČR GA203/07/0886; GA ČR GA203/08/1536 Institutional research plan: CEZ:AV0Z40310501 Keywords : oxygenated aromatics * solubility * pressurized hot water Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.695, year: 2009 8. HTGR power plant hot reheat steam pressure control system International Nuclear Information System (INIS) Braytenbah, A.S.; Jaegtnes, K.O. 1975-01-01 A control system for a high temperature gas cooled reactor (HTGR) power plant is disclosed wherein such plant includes a plurality of steam generators. Dual turbine-generators are connected to the common steam headers, a high pressure element of each turbine receiving steam from the main steam header, and an intermediate-low pressure element of each turbine receiving steam from the hot reheat header. Associated with each high pressure element is a bypass line connected between the main steam header and a cold reheat header, which is commonly connected to the high pressure element exhausts. A control system governs the flow of steam through the first and second bypass lines to provide for a desired minimum steam flow through the steam generator reheater sections at times when the total steam flow through the turbines is less than such minimum, and to regulate the hot reheat header steam pressure to improve control of the auxiliary steam turbines and thereby improve control of the reactor coolant gas flow, particularly following a turbine trip. (U.S.) 9. Effects of internal gas pressure and microstructure on the mechanisms of hot-pressing and swelling in ceramics. Progress report, June 1, 1975--March 31, 1976 International Nuclear Information System (INIS) Solomon, A.A. 1976-02-01 Pressurization system components for studying the hot-pressing and swelling behavior of CoO were built. A vacuum furnace was modified so that dimensional changes can be continuously monitored during sintering under high vacuum. Chracterization of the CoO starting powders was initiated. A technique was developed to form geometrically uniform pellet compacts of high green density using low pressure punch and die pressing followed by high pressure isostatic compaction to obtain uniform green density. Preliminary sintering experiments were carried out at 1 atm in air, inert gas, and under vacuum with specimen deflection continuously monitored. Resulting microstructures were characterized using mercury porosimetry and quantitative optical microscopy. Drastic differences in sintering rates in vacuum and air were observed 10. Thermal stability of the grain structure in the W-2V and W-2V-0.5Y2O3 alloys produced by hot isostatic pressing International Nuclear Information System (INIS) Martínez, J.; Savoini, B.; Monge, M.A.; Muñoz, A.; Armstrong, D.E.J.; Pareja, R. 2013-01-01 Highlights: • W-2V and ODS W-2V-0.5Y 2 O 3 alloys have been produced following a powder metallurgy route. • Grain microstructure and microhardness have been studied after isothermal treatments in vacuum. • Both alloys exhibit a duplex grain size population: a submicron-sized grain and a coarse grained one. • The Y 2 O 3 addition inhibits growth of the coarse grains for T 2 O 3 nanoparticles enhance the microhardness of W-2V-0.5Y 2 O 3 . -- Abstract: W-2V and ODS W-2V-0.5Y 2 O 3 alloys have been produced following a powder metallurgy route consisting of mechanical alloying and a subsequent high isostatic pressing HIP at 1573 K. The grain microstructure and microhardness recovery of the alloys have been studied in samples subjected to isothermal treatments in vacuum in temperature range 1073–1973 K. Both alloys exhibit a duplex grain size distribution consisting of a submicron-sized grain and a coarse-grained population. It has been found that the Y 2 O 3 addition inhibits growth of the coarse grains at T 2 O 3 , respectively, was observed at T ≥ 1573 K. It resulted that the rate constant for grain growth is 30 times higher in W-2V-0.5Y 2 O 3 than in W-2V. The considerable enhancement of the microhardness in the W-2V-0.5Y 2 O 3 appears to be associated to dispersion strengthening 11. Nevada Isostatic Gravity Grid Data.gov (United States) National Oceanic and Atmospheric Administration, Department of Commerce — A 2 kilometer Isostatic anomaly grid for the state of Nevada. Number of columns is 269 and number of rows is 394. The order of the data is from the lower left to the... 12. Drilling and testing hot, high-pressure wells Energy Technology Data Exchange (ETDEWEB) MacAndrew, R. (Ranger Oil Ltd, Aberdeen (United Kingdom)); Parry, N. (Phillips Petroleum Company United Kingdom Ltd, Aberdeen (United Kingdom)); Prieur, J.M. (Conoco UK Ltd, Aberdeen (United Kingdom)); Wiggelman, J. (Shell UK Exploration and Production, Aberdeen (United Kingdom)); Diggins, E. (Brunei Shell Petroleum (Brunei Darussalam)); Guicheney, P. (Sedco Forex, Montrouge (France)); Cameron, D.; Stewart, A. (Dowell Schlumberger, Aberdeen (United Kingdom)) Meticulous planning and careful control of operations are needed to safely drill and test high-temperature, high-pressure (HTHP) wells. Techniques, employed in the Central Graben in the UK sector of the North Sea, where about 50 HTHP wells have been drilled, are examined. Three main areas of activity are covered in this comprehensive review: drilling safety, casing and cementation, and testing. The three issues at the heart of HTHP drilling safety are kick prevention, kick detection and well control. Kicks are influxes of reservoir fluid into the well. Test equipment and operations are divided into three sections: downhole, subsea and surface. Also details are given of how this North Sea experience has been used to help plan a jackup rig modification for hot, high-pressure drilling off Brunei. 16 figs., 32 refs. 13. Transition density and pressure in hot neutron stars International Nuclear Information System (INIS) Xu Jun; Chen Liewen; Ko, Che Ming; Li Baoan 2010-01-01 Using the momentum-dependent effective interaction (MDI) for nucleons, we have studied the transition density and pressure at the boundary between the inner crust and the liquid core of hot neutron stars. We find that their values are larger in neutrino-trapped neutron stars than in neutrino-free neutron stars. Furthermore, both are found to decrease with increasing temperature of a neutron star as well as increasing slope parameter of the nuclear symmetry energy, except that the transition pressure in neutrino-trapped neutron stars for the case of small symmetry energy slope parameter first increases and then decreases with increasing temperature. We have also studied the effect of the nuclear symmetry energy on the critical temperature above which the inner crust in a hot neutron star disappears and found that with increasing value of the symmetry energy slope parameter, the critical temperature decreases slightly in neutrino-trapped neutron stars but first decreases and then increases in neutrino-free neutron stars. 14. Microstructure and Mechanical Properties of Long Ti-6Al-4V Rods Additively Manufactured by Selective Electron Beam Melting Out of a Deep Powder Bed and the Effect of Subsequent Hot Isostatic Pressing Science.gov (United States) Lu, S. L.; Tang, H. P.; Ning, Y. P.; Liu, N.; StJohn, D. H.; Qian, M. 2015-09-01 An array of eight long Ti-6Al-4V rods (diameter: 12 mm; height: 300 mm) have been additively manufactured, vertically and perpendicular to the powder bed, by selective electron beam melting (SEBM). The purpose was to identify and understand the challenges of fabricating Ti-6Al-4V samples or parts from a deep powder bed (more than 200-mm deep) by SEBM and the necessity of applying post heat treatment. The resulting microstructure and mechanical properties of these Ti-6Al-4V rods were characterized along their building ( i.e., axial) direction by dividing each rod into three segments (top, middle, and bottom), both before ( i.e., as-built) and after hot isostatic pressing (HIP). The as-built microstructure of each rod was inhomogeneous; it was coarsest in the top segment, which showed a near equilibrium α- β lamellar structure, and finest in the bottom segment, which featured a non-equilibrium mixed structure. The tensile properties varied along the rod axis, especially the ductility, but all tensile properties met the requirements specified by ASTM F3001-14. HIP increased the relative density from 99.03 pct of the theoretical density (TD) to 99.90 pct TD and homogenized the microstructure thereby leading to highly consistent tensile properties along the rod axis. The temperature of the stainless steel substrate used in the powder bed was monitored. The as-built inhomogeneous microstructure is attributed to the temperature gradient in the deep powder bed. Post heat treatment is thus necessary for Ti-6Al-4V samples or parts manufactured from a deep powder bed by SEBM. This differs from the additive manufacturing of small samples or parts from a shallow powder bed (less than 100-mm deep) by SEBM. 15. Hot-isostatic pressing (HIP). Pt. 2 International Nuclear Information System (INIS) Bayer, E.; Moser, G.; Seilstorfer, H. 1981-01-01 After the description of the microstructure and strengthening mechanism of nickel- and cobalt-base superalloys, claims for the production of suitable powders for the HIP-technology are pointed out and methods to its realization are discussed. Taking the manufacture of turbine discs (ultrasonic form) as an example the possibilities of the near-net-shape-technology are shown. Investigations on mechanical properties and on microstructures are carried out to determine the effect of HIP-process-parameters on these features. (orig.) [de 16. Technical specifications of variable speed motors for negative pressure control in hot cell area Energy Technology Data Exchange (ETDEWEB) Kim, Seon Duk; Bang, H. S.; Cho, W. K 2002-01-01 Hot cells are the facilities for handling the high radioactive materials and various R and D activities are performed using hot cells. Therefore the control of air flow in hot cell area is very important technology and it is started with the variable speed motor(VSM) controlling the air handling system in that area. This report describes various technical aspects of VS motors and will be useful for understanding the practical technologies of VS motors and also for optimization of the negative pressure controls in hot cell area. 17. Kinetics of Pressurized Water Reactors with Hot or Cold Moderators Energy Technology Data Exchange (ETDEWEB) Norinder, O 1960-11-15 The set of neutron kinetic equations developed in this report permits the use of long integration steps during stepwise integration. Thermal relations which describe the transfer of heat from fuel to coolant are derived. The influence upon the kinetic behavior of the reactor of a number of parameters is studied. A comparison of the kinetic properties of the hot and cold moderators is given. 18. High pressure, low pressure and hot water heating systems in hospitals. Hochdruck-, Niederdruck- und Warmwasserheizungsanlagen im Krankenhaus Energy Technology Data Exchange (ETDEWEB) Riedle, K [H. Riedle GmbH, Wiesbaden (Germany) 1994-07-01 In hospital nowadays the limitation of the use of steam boilers and their direct supply network to the possible minimum is aimed at when the heating system is exchanged or retrofitted. Independent of the fact whether high pressure or low pressure steam or hot water is used the optimum water treatment should be carried out with a minimum of chemical substances. Here hydroquinone, neutralizing amines, carbohydrazide, sodium sulphite and tannins can be used. The dimensioning of hot water heating circuits is shown with examples. (BWI) 19. Nickel powders shape effect upon their isostatic compaction behavior International Nuclear Information System (INIS) Cytermann, R.; Auguin, B.; Defresne, A.; Gilles, P. 1975-01-01 Two carbonyl nickel powders of the same purity, one spherical, the other of very irregular shape, were isostatically compacted at pressures from 0.5 to 13Kbars with two compacting speeds: 1Kbar/s and 1Kbar/15s. The influence of the powder shapes on the electrical resistivity, tensile strength and microcalorimetric measurements was studied [fr 20. Improving hot-spot pressure for ignition in high-adiabat Inertial Confinement Fusion implosion OpenAIRE Kang, Dongguo; Zhu, Shaoping; Pei, Wenbing; Zou, Shiyang; Zheng, Wudi; Gu, Jianfa; Dai, Zhensheng 2017-01-01 A novel capsule target design to improve the hot-spot pressure in the high-adiabat implosion for inertial confinement fusion is proposed, where a layer of comparatively high-density material is used as a pusher between the fuel and the ablator. This design is based on our theoretical finding of the stagnation scaling laws, which indicates that the hot spot pressure can be improved by increasing the kinetic energy density $\\rho_d V_{imp}^2/2$ ($\\rho_d$ is the shell density when the maximum she... 1. Quantum dots of Cd0.5Mn0.5Te semimagnetic semiconductor formed by the cold isostatic pressure method International Nuclear Information System (INIS) Contreras, O.; Power, Ch.; Quintero, M.; Morocoima, M.; Tovar, R.; Quintero, E.; Gonzalez, J.; Munoz-San Jose, V.; Broto, J.M.; Snoeck, E. 2005-01-01 Cd 0.5 Mn 0.5 Te is a semimagnetic semiconductor, which crystallizes in the zinc-blende structure (ZB) and exhibits a magnetic spin glass like transition at 21 K. Under pressure it shows a first-order phase transition around 2.6 GPa to the NaCl like structure. In this work, the pressure cycled method using a Paris-Edinburgh cell up to 8 GPa has been applied to Cd 0.5 Mn 0.5 Te samples in order to obtain recovered nanocrystals. The nanoparticles have been characterized by EDX and electron microscopy. The X-ray and electron diffraction results confirmed the existence of nanocrystals in the ZB phase with an average size of 7 nm. Magnetization measurements made in the range of 2-300 K at low field show that the temperature of the magnetic transition decreases when the crystallites' size is reduced 2. Pressurized hot water extraction of proteins from Sambucus nigra L. branches Czech Academy of Sciences Publication Activity Database Šalplachta, Jiří; Hohnová, Barbora 2017-01-01 Roč. 108, DEC (2017), s. 312-315 ISSN 0926-6690 Grant - others:GA AV ČR(CZ) R200311521 Institutional support: RVO:68081715 Keywords : elderberry * pressurized hot water extraction * proteins Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 3.181, year: 2016 3. Effect of pressurized hot water extraction on antioxidants from grape pomace before and after enological fermentation. Science.gov (United States) Vergara-Salinas, José R; Bulnes, Pedro; Zúñiga, María Carolina; Pérez-Jiménez, Jara; Torres, Josep Lluís; Mateos-Martín, María Luisa; Agosin, Eduardo; Pérez-Correa, José R 2013-07-17 Grape pomace was extracted with pressurized hot water at laboratory scale before and after fermentation to explore the effects of fermentation and extraction temperature (50-200 °C) and time (5 and 30 min) on total extracted antioxidant levels and activity and to determine the content and recovery efficiency of main grape polyphenols, anthocyanins, and tannins. Fermented pomace yielded more total antioxidants (TAs), antioxidant activity, and tannins, than unfermented pomace but fewer anthocyanins. Elevating the extraction temperature increased TA extraction and antioxidant activity. Maximum anthocyanin extraction yields were achieved at 100 °C and at 150 °C for tannins and tannin-anthocyanin adducts. Using higher temperatures and longer extraction times resulted in a sharp decrease of polyphenol extraction yield. Relevant proanthocyanidin amounts were extracted only at 50 and 100 °C. Finally, TA recovery and activity were not directly related to the main polyphenol content when performing pressurized hot water grape pomace extraction. 4. Hot hardness studies on zircaloy 2 pressure tube along three orientations International Nuclear Information System (INIS) Kutty, T.R.G.; Ravi, K.; Jarvis, T.; Sengupta, A.K.; Majumdar, S.; Tewari, R.; Shrivastava, D.; Dey, G.K. 2002-01-01 Zirconium based alloys are the natural choice for both the fuel element cans and in-core structural components in water cooled nuclear reactors. In this paper, the hot hardness behaviour of zircaloy 2 pressure tubes has been examined from room temperature to 400 degC using a hot hardness tester. For the purpose of comparison, the hardness of the as cast and room temperature rolled specimens has also been carried out. For this, the samples were cut along three orientations and hardness was measured in each of these directions using Vickers diamond pyramid indenter. The variation in hardness of the pressure tube samples show that the hardness was highest along circumferential direction and least along the axial direction. The room temperature rolled samples showed highest hardness along the rolling planes. These variations in hardness could be explained in terms of development of texture during working on the material. (author) 5. Thermal stability of the grain structure in the W-2V and W-2V-0.5Y{sub 2}O{sub 3} alloys produced by hot isostatic pressing Energy Technology Data Exchange (ETDEWEB) Martínez, J.; Savoini, B.; Monge, M.A. [Departamento de Física, Universidad Carlos III de Madrid, 28911-Leganés Madrid (Spain); Muñoz, A., E-mail: [email protected] [Departamento de Física, Universidad Carlos III de Madrid, 28911-Leganés Madrid (Spain); Armstrong, D.E.J. [Department of Materials, University of Oxford, Park Road, Oxford OX1 3PH (United Kingdom); Pareja, R. [Departamento de Física, Universidad Carlos III de Madrid, 28911-Leganés Madrid (Spain) 2013-10-15 Highlights: • W-2V and ODS W-2V-0.5Y{sub 2}O{sub 3} alloys have been produced following a powder metallurgy route. • Grain microstructure and microhardness have been studied after isothermal treatments in vacuum. • Both alloys exhibit a duplex grain size population: a submicron-sized grain and a coarse grained one. • The Y{sub 2}O{sub 3} addition inhibits growth of the coarse grains for T < 1973 K. • The Y{sub 2}O{sub 3} nanoparticles enhance the microhardness of W-2V-0.5Y{sub 2}O{sub 3}. -- Abstract: W-2V and ODS W-2V-0.5Y{sub 2}O{sub 3} alloys have been produced following a powder metallurgy route consisting of mechanical alloying and a subsequent high isostatic pressing HIP at 1573 K. The grain microstructure and microhardness recovery of the alloys have been studied in samples subjected to isothermal treatments in vacuum in temperature range 1073–1973 K. Both alloys exhibit a duplex grain size distribution consisting of a submicron-sized grain and a coarse-grained population. It has been found that the Y{sub 2}O{sub 3} addition inhibits growth of the coarse grains at T < 1973 K. Submicron grain growth, with activation enthalpy of 1.9 and 2.49 eV for W-2V and W-2V-0.5Y{sub 2}O{sub 3}, respectively, was observed at T ≥ 1573 K. It resulted that the rate constant for grain growth is 30 times higher in W-2V-0.5Y{sub 2}O{sub 3} than in W-2V. The considerable enhancement of the microhardness in the W-2V-0.5Y{sub 2}O{sub 3} appears to be associated to dispersion strengthening. 6. Compaction creep of quartz sand at 400-600°C: Experimental evidence for dissolution-controlled pressure solution NARCIS (Netherlands) Niemeijer, A.; Spiers, C.J.; Bos, B. 2002-01-01 Intergranular pressure solution (IPS) is an important compaction and deformation mechanism in quartzose rocks, but the kinetics and rate-controlling process remain unclear. The aim of the present study is to test microphysical models for compaction creep by IPS against isostatic hot pressing 7. Microwave combustion and sintering without isostatic pressure International Nuclear Information System (INIS) Ebadian, M.A. 1998-01-01 In recent years interest has grown rapidly in the application of microwave energy to the processing of ceramics, composites, polymers, and other materials. Advances in the understanding of microwave/materials interactions will facilitate the production of new ceramic materials with superior mechanical properties. One application of particular interest is the use of microwave energy for the mobilization of uranium for subsequent redeposition. Phase III (FY98) will focus on the microwave assisted chemical vapor infiltration tests for mobilization and redeposition of radioactive species in the mixed sludge waste. Uranium hexachloride and uranium (IV) borohydride are volatile compounds for which the chemical vapor infiltration procedure might be developed for the separation of uranium. Microwave heating characterized by an inverse temperature profile within a preformed ceramic matrix will be utilized for CVI using a carrier gas. Matrix deposition is expected to commence from the inside of the sample where the highest temperature is present. The preform matrix materials, which include aluminosilicate based ceramics and silicon carbide based ceramics, are all amenable to extreme volume reduction, densification, and vitrification. Important parameters of microwave sintering such as frequency, power requirement, soaking temperature, and holding time will be investigated to optimize process conditions for the volatilization of uranyl species using a reactive carrier gas in a microwave chamber 8. Structure and hardness of TiAl-TiB2 composite prepared by hot isostatic pressing of mechanically alloyed powders. Mekanikaru aroingu funmatsu no HIP shoketsu ni yori sakuseishita TiAl/TiB2 fukugo zairyo no soshiki to kodo Energy Technology Data Exchange (ETDEWEB) Sato, T; Shimakage, K [Muroran Inst. of Technology, Hokkaido (Japan). Faculty of Engineering; Miyakawa, S [Muroran Inst. of Technology, Hokkaido (Japan). Graduate Student 1992-11-20 The practical application of Ti-Al system intermetallic compounds is expected as an advanced light heat resistant material. TiAl group out of them, as for the specific strength, has an equivalent maximum working temperature as that of the nickel base alloy, which is utilized as a turbine material for the current aircraft, and moreover it is also said that it is superior in the creep and rupture properties to the latter. In this study, by mechanical alloying (MA) of each mixed powder of Ti-Al and Ti-B, by suing heptane as a grinding aid, each MA powder of the amorphous TiAl containing carbon and extremely fine compound TiB2 were prepared, and subsequently the true density sintering by the hot isostatic pressing (HIP) was performed, and by doing these, the preparation of TiAl/TiB2 system composite material with a high composite ratio of TiO2 was tried. Consequently, by the MA treatment of the mixed powder of Ti and B for more than 50 hours, the compound powder of TiB2 mixed with TiB could be prepared, and its hardness has shown the maximum value Hmv=l200 with a composition of TiAl/25 mol % TiB2. 14 refs., 10 figs., 2 tabs. 9. Hot Gas Cleanup Test Facility for gasification and pressurized combustion. Quarterly report, October--December 1994 Energy Technology Data Exchange (ETDEWEB) NONE 1995-02-01 The objective of this project is to evaluate hot gas particle control technologies using coal-derived gas streams. This will entail the design, construction, installation, and use of a flexible test facility which can operate under realistic gasification and combustion conditions. The major particulate control device issues to be addressed include the integration of the particulate control devices into coal utilization systems, on-line cleaning techniques, chemical and thermal degradation of components, fatigue or structural failures, blinding, collection efficiency as a function of particle size, and scale-up of particulate control systems to commercial size. The conceptual design of the facility was extended to include a within scope, phased expansion of the existing Hot Gas Cleanup Test Facility Cooperative Agreement to also address systems integration issues of hot particulate removal in advanced coal-based power generation systems. This expansion included the consideration of the following modules at the test facility in addition to the original Transport Reactor gas source and Hot Gas Cleanup Units: carbonizer/pressurized circulating fluidized bed gas source; hot gas cleanup units to mate to all gas streams; combustion gas turbine; and fuel cell and associated gas treatment. The major emphasis during this reporting period was continuing the detailed design of the facility and integrating the particulate control devices (PCDs) into structural and process designs. Substantial progress in underground construction activities was achieved during the quarter. Delivery and construction of coal handling and process structural steel began during the quarter. Delivery and construction of coal handling and process structural steel began during the quarter. MWK equipment at the grade level and the first tier are being set in the structure. 10. Towards 4-loop NSPT result for a 3-dimensional condensate-contribution to hot QCD pressure CERN Document Server Torrero, C.; Schroder, Y.; Di Renzo, F.; Miccio, V. 2007-01-01 Thanks to dimensional reduction, the contributions to the hot QCD pressure coming from so-called soft modes can be studied via an effective three-dimensional theory named Electrostatic QCD (spatial Yang-Mills fields plus an adjoint Higgs scalar). The poor convergence of the perturbative series within EQCD suggests to perform lattice measurements of some of the associated gluon condensates. These turn out, however, to be plagued by large discretization artifacts. We discuss how Numerical Stochastic Perturbation Theory can be exploited to determine the full lattice spacing dependence of one of these condensates up to 4-loop order, and sharpen our tools on a concrete 2-loop example. 11. Isostatic Model and Isostatic Gravity Anomalies of the Arabian Plate and Surroundings OpenAIRE M. K. Kaban; Sami El Khrepy; Nassir Al-Arifi 2016-01-01 The isostatic modeling represents one of the most useful ‘‘geological’’ reduction methods of the gravity field. With the isostatic correction, it is possible to remove a significant part of the effect of deep density heterogeneity, which dominates in the Bouguer gravity anomalies. Although there exist several isostatic compensation schemes, it is usually supposed that a choice of the model is not an important factor to first order, since the total weight of compensating m... 12. Buoyancy and Pressure Driven Flow of Hot Gases in Vertical Shafts with Natural and Forced Ventilation Science.gov (United States) Tamm, Gunnar; Jaluria, Yogesh 2003-11-01 An experimental investigation has been carried out on the buoyancy and pressure induced flow of hot gases in vertical shafts, in order to simulate the propagation of combustion products in elevator shafts due to fire in multilevel buildings. Various geometrical configurations are studied, with regard to natural and forced ventilation imposed at the top or bottom of the vertical shaft. The aspect ratio is taken at a fixed value of 6 and the inflow conditions for the hot gases, at a vent near the bottom, are varied in terms of the Reynolds and Grashof numbers. Temperature measurements within the shaft allow a detailed study of the steady state thermal fields, from which optimal means for smoke alleviation in high-rise building fires may be developed. Flow visualization is also used to study the flow characteristics. The results obtained indicate a wall plume as the primary transport mechanism. Flow recirculation dominates at high Grashof number flows, while increased Reynolds numbers gives rise to greater mixing in the shaft. The development and stability of the flow and its effect on the spread of smoke and hot gases are assessed for the different shaft configurations and inlet conditions. It is found that the fastest smoke removal and lowest shaft temperatures occur for a configuration with natural ventilation at the top and forced ventilation up from the shaft bottom. It is also shown that forced ventilation can be used to arrest smoke spread, as well as to dilute the effects of the fire. 13. U.S. Isostatic Residual Gravity Grid Data.gov (United States) National Oceanic and Atmospheric Administration, Department of Commerce — isores.bin - standard grid containing isostatic residual gravity map for U.S. Grid interval = 4 km. Projection is Albers (central meridian = 96 degrees West; base... 14. Effects of high shock pressures and pore morphology on hot spot mechanisms in HMX Science.gov (United States) Springer, H. K.; Tarver, C. M.; Bastea, S. 2017-01-01 The shock initiation and detonation behavior of heterogeneous solid explosives is governed by its microstructure and reactive properties. New additive manufacturing techniques offer unprecedented control of explosive microstructures previously impossible, enabling us to develop novel explosives with tailored shock sensitivity and detonation properties. Since microstructure-performance relationships are not well established for explosives, there is little material design guidance for these manufacturing techniques. In this study, we explore the effects of high shock pressures (15-38 GPa) with long shock durations and different pore morphologies on hot spot mechanisms in HMX. HMX is chosen as the model material because we have experimental data on many of the chemical-thermal-mechanical properties required for pore collapse simulations. Our simulations are performed using the multi-physics arbitrary Lagrangian Eulerian finite element hydrocode, ALE3D, with Cheetah-based models for the unreacted and the product equation-of-states. We use a temperature-dependent specific heat with the unreacted equation-of-state and a temperature-dependent viscosity model to ensure accurate shock temperatures for subsequent chemistry. The Lindemann Law model is used for shock melting in HMX. In contrast to previous pore collapse studies at lower shock pressures (≤10 GPa) in HMX and shorter post-collapse burning times, our calculations show that shock melting occurs above 15 GPa due to higher bulk heating and a prominent elongated ("jet-like") hot spot region forms at later times. The combination of the elongated, post-collapse hot spot region and the higher bulk heating with increasing pressure dramatically increases the growth rate of reaction. Our calculations show that the reaction rate, dF/dt, increases with increasing shock pressure. We decompose the reaction rate into ignition ((dF/dt)ig) and growth ((dF/dt)gr) phases to better analyze our results. We define the ignition phase 15. The isostatic state of Mead crater Science.gov (United States) Banerdt, W. B.; Konopliv, A. S.; Rappaport, N. J.; Sjogren, W. L.; Grimm, R. E.; Ford, P. G. 1994-01-01 We have analyzed high-resolution Magellan Doppler tracking data over Mead crater, using both line-of-sight and spherical harmonic methods, and have found a negative gravity anomaly of about 4-5 mgal (at spacecraft altitude, 182 km). This is consistent with no isostatic compensation of the present topography; the uncertainty in the analysis allows perhaps as much as 30% compensation at shallow dpeths (approximately 25 km). This is similar to observations of large craters on Earth, which are not generally compensated, but contrasts with at least some lunar basins which are inferred to have large Moho uplifts and corresponding positive Bouguer anomalies. An uncompensated load of this size requires a lithosphere with an effective elastic lithosphere thickness greater than 30 km. In order for the crust-mantle boundary not to have participated in the deformation associated with the collapse of the transient cavity during the creation of the crater, the yield strength near the top of the mantle must have been significantly higher on Earth and Venus than on the Moon at the time of basin formation. This might be due to increased strength against frictional sliding at the higher confining pressures within the larger planets. Alternatively, the thinner crusts of Earth and Venus compared to that of the Moon may result in higher creep strength of the upper mantle at shallower depths. 16. Experimental study on vapor explosion induced by pressure pulse in coarse mixing of hot molten metal and water International Nuclear Information System (INIS) Inoue, A.; Tobita, Y.; Aritomi, M.; Takahashi, M.; Matsuzaki, M. 2004-01-01 An experimental study was done to investigate characteristics of metal-water interaction, when a mount of hot liquid metal is injected into the water. The test section is a vertical shock tube of 60mm in inner diameter and 1200mm in length. A special injector which is designed to inject hot metal of controlled volume and flow rate is attached at the top of the tube. When the hot metal is injected in the water and comes down at a position of the test vessel, a trigger pressure pulse is generated at the bottom of the test tube. Local transient pressures along the tube are measured by piezo pressure transducers. The following items were investigated in the experiment; 1) The criteria to cause a vapor explosion, 2) Transient behaviors and propagation characteristics of pressure wave in the mixing region. 3) Effects of triggering pulse, injection temperature and mass of hot molten metal on the peak pressure. The probability of the vapor explosion jumped when the interface temperature at the molten metal-water direct contact is higher than the homogeneous nucleation temperature of water and the triggering pulse becomes larger than 0.9MPa. Two types of the pressure propagation modes are observed, one is the detonative mode with a sharp rise and other is usual pressure mode with a mild rise. (author) 17. Theoretical study of hydraulic jump during circular horizontal hot leg injection in pressurized water reactor International Nuclear Information System (INIS) El Hawary, Shehab; Abu-Elyazeed, Osayed S.M.; Fahmy, Adel Alyan; Meglaa, Khairy 2016-01-01 Highlights: • The model is developed to predict the occurrence of onset hydraulic jump in a circular pipe. • Theoretical results are in agreement with experimental results and theory. • Effects of diameter of the injection pipe, Froude number and injected coolant mass are studied. - Abstract: One important phenomenon occurring during Loss of Coolant Accident (LOCA) is Counter-Current Flow Limitation (CCFL). The incidence of such CCFL is introduced by the onset of hydraulic jump. In the present work, a one dimensional model was modified to fit circular hot channel. The model was used to study the factors affecting the initial Froude number, the location of the occurrence of the hydraulic jump, and the critical coolant flow depth during circular horizontal hot leg injection in US-APWR Mitsubishi Reactor. The results showed good agreement with published experimental data of the Upper Plenum Test Facility (UPTF) at Mannheim, Germany. It was found that higher injected coolant mass flow rate increases the initial Froude number, the location of the occurrence of the hydraulic jump, and the critical injection depth divided by the diameter of the injection pipe. Such behavior is thought to be due to the increase of the inertia force by increasing of the injected coolant mass flow rate and the inverse of the diameter of the injection pipe. It was found also that, the location of the occurrence of hydraulic jump increases with decreasing load effect. Therefore, these results reveal that the avoidance of CCFL as well as hydraulic jump through hot leg at maximum load can be achieved by decreasing the distance between the injection point and the pressure vessel to below 0.3 m, and with diameter of 4 in (10.16 cm) as the design diameter of the injection pipe in US-APWR Mitsubishi Reactor. Moreover, the maximum critical depth (56 cm) is less than the diameter of the hot leg (78.74 cm) at an injected coolant mass flow of 400 kg/s, and with diameter of 4 in (10.16 cm) as the 18. Preparation of amorphous-crystalline SiO{sub 2} composite by hot isostatic pressing (HIP). 2; HIP ho ni yoru SiO{sub 2} kei hishoshitsu-kesshoshitsu fukugo zairyo no sakusei. 2 Energy Technology Data Exchange (ETDEWEB) Ito, S.; Nishii, J.; Fujii, T.; Akashi, K. [Science University of Tokyo, Tokyo (Japan). Faculty of Science and Tecnology 2000-08-15 The composites consisting of {alpha}-quartz crystallites and amorphous SiO{sub 2} were prepared by HIP technique, imitating the structure of natural agate. In the previous study, the K{sub IC} of the composite prepared from the mixed powder of crystallites and amorphous SiO{sub 2} was comparable to that of the natural agate (0.56MN/m{sup 1.5}). In this study, to increase the toughness of the composite, (1) the mixture of silica sol and {alpha}-quartz powder and (2) silica sol including nucleation promoter were examined as starting materials respectively. These starting materials were pressed into powder compacts with {phi} 10 multiplied 50mm in size. The Pyrex glass capsule containing the compact was hipped at 800-1,200 degrees C for 0-120 minutes under the pressure of 200 MPa. The K{sub IC} of the composite obtained from the mixture of silica sol and {alpha}-quartz powder was equivalent to that obtained in the previous study, while the maximum K{sub IC} (0.63 MN/m{sup 1.5}) was obtained when PbCl{sub 2} was used as a nucleation promoter. The nucleation promoter having low solubility in water was useful for the homogeneous generation of the crystallites. (author) 19. Hot granules medium pressure forming process of AA7075 conical parts Science.gov (United States) Dong, Guojiang; Zhao, Changcai; Peng, Yaxin; Li, Ying 2015-05-01 High strength aluminum alloy plate has a low elongation at room temperature, which leads to the forming of its components need a high temperature. Liquid or gas is used as the pressure-transfer medium in the existing flexible mould forming process, the heat resistance of the medium and pressurizing device makes the application of aluminum alloy plate thermoforming restricted. To solve this problem, the existing medium is replaced by the heat-resisting solid granules and the general pressure equipments are applied. Based on the pressure-transfer performance test of the solid granules medium, the feasibility that the assumption of the extended Drucker-Prager linear model can be used in the finite element analysis is proved. The constitutive equation, the yield function and the theoretical forming limit diagram(FLD) of AA7075 sheet are established. Through the finite element numerical simulation of hot granules medium pressure forming(HGMF) process, not only the influence laws of the process parameters, such as forming temperature, the blank-holder gap and the diameter of the slab, on sheet metal forming performance are discussed, but also the broken area of the forming process is analyzed and predicted, which are coincided with the technological test. The conical part whose half cone angle is 15° and relative height H/d 0 is 0.57, is formed in one process at 250°C. The HGMF process solves the problems of loading and seal in the existing flexible mould forming process and provides a novel technology for thermoforming of light alloy plate, such as magnesium alloy, aluminium alloy and titanium alloy. 20. Methodology for the investigation of ignition near hot surfaces in a high-pressure shock tube Science.gov (United States) Niegemann, P.; Fikri, M.; Wlokas, I.; Röder, M.; Schulz, C. 2018-05-01 Autoignition of fuel/air mixtures is a determining process in internal combustion engines. Ignition can start either homogeneously in the gas phase after compression or in the vicinity of hot surfaces. While ignition properties of commercial fuels are conventionally described by a single quantity (octane number), it is known that some fuels have a varying propensity to the two processes. We present a new experimental concept that generates well-controlled temperature inhomogeneities in the shock-heated gases of a high-pressure shock tube. A shock-heated reactive mixture is brought into contact with a heated silicon nitride ceramic glow plug. The glow-plug temperature can be set up to 1200 K, higher than the post-reflected-shock gas temperatures (650-1050 K). High-repetition-rate chemiluminescence imaging is used to localize the onset of ignition in the vicinity of the hot surface. In experiments with ethanol, the results show that in most cases under shock-heated conditions, the ignition begins inhomogeneously in the vicinity of the glow plug and is favored because of the high wall temperature. Additionally, the interaction of geometry, external heating, and gas-dynamic effects was investigated by numerical simulations of the shock wave in a non-reactive flow. 1. Hydrothermal Treatment of Cellulose in Hot-Pressurized Water for the Production of Levulinic Acid Directory of Open Access Journals (Sweden) ASLI YUKSEL 2016-12-01 Full Text Available In this paper, hot-pressurized water, operating above boiling point and below critical point of water (374. 15 °C and 22.1 MPa, was used as a reaction medium for the decomposition of cellulose to high-value chemicals, such levulinic acid. Effects of reaction temperature, pressure, time, external oxidant type and concentration on the cellulose degradation and product distribution were evaluated. In order to compare the cellulose decomposition and yields of levulinic acid, experiments were performed with and without addition of oxidizing agents (H2SO4 and H2O2. Analysis of the liqueur was monitored by HPLC and GC-MS at different temperatures (150 - 280 °C, pressures (5-64 bars and reaction times (30 - 120 mins. Levulinic acid, 5-HMF and formic acid were detected as main products. 73% cellulose conversion was achieved with 38% levulinic acid yield when 125 mM of sulfuric acid was added to the reaction medium at 200 °C for 60 min reaction time. 2. The Relation between Hot Flashes and Ambulatory Blood Pressure: The Hilo Women’s Health Study Science.gov (United States) Brown, Daniel E.; Sievert, Lynnette L.; Morrison, Lynn A.; Rahberg, Nichole; Reza, Angela 2011-01-01 Objectives Hot flashes (HFs) have been associated with elevated blood pressure, but studies have not examined the relationship between objectively measured HFs and blood pressure during normal daily activities. The objectives of this study are to examine ambulatory blood pressure (BP) differences between women who report HFs and those who do not, and to observe whether an objectively measured HF is associated with transient changes in BP. Methods A sample of 202 women in Hilo, Hawaii aged 45–55 years were asked to fill out a questionnaire that included demographic information and an inventory of symptoms. The women underwent simultaneous 24-hour monitoring of ambulatory BP and HFs, while keeping a diary that included mood and HF reports. Results No significant difference was present in mean BP between women who reported having a HF during the past 2 weeks and those who did not. When measurements controlled for negative mood reports and posture, there was a highly significant elevation in Z scores of systolic BP when a measured, objective HF occurred within 10 minutes preceding a BP reading, and a significant elevation of Z scores of diastolic BP when a subjectively reported HF occurred within 10 minutes after a BP reading. Conclusions These results suggest that objectively measured HFs precede transient elevations of systolic BP, but it is unclear if there is a causal relationship. These results also suggest that women experience subjective HFs within 10 minutes after a transient increase in diastolic BP. Again, the causal relationship is not understood. PMID:21183716 3. Pressurized Hot Water Extraction of anthocyanins from red onion: A study on extraction and degradation rates Energy Technology Data Exchange (ETDEWEB) Petersson, Erik V.; Liu Jiayin; Sjoeberg, Per J.R.; Danielsson, Rolf [Uppsala University, Department of Physical and Analytical Chemistry, P.O. Box 599, SE-751 24, Uppsala (Sweden); Turner, Charlotta, E-mail: [email protected] [Uppsala University, Department of Physical and Analytical Chemistry, P.O. Box 599, SE-751 24, Uppsala (Sweden) 2010-03-17 Pressurized Hot Water Extraction (PHWE) is a quick, efficient and environmentally friendly technique for extractions. However, when using PHWE to extract thermally unstable analytes, extraction and degradation effects occur at the same time, and thereby compete. At first, the extraction effect dominates, but degradation effects soon take over. In this paper, extraction and degradation rates of anthocyanins from red onion were studied with experiments in a static batch reactor at 110 deg. C. A total extraction curve was calculated with data from the actual extraction and degradation curves, showing that more anthocyanins, 21-36% depending on the species, could be extracted if no degradation occurred, but then longer extraction times would be required than those needed to reach the peak level in the apparent extraction curves. The results give information about the different kinetic processes competing during an extraction procedure. 4. Blood Pressure Treatment Adherence and Control after Participation in the ReHOT Directory of Open Access Journals (Sweden) Nathália Silva de Jesus Full Text Available Abstract Background: Lack of adherence to pharmacological treatment is one of the main causes of low control rates in hypertension. Objective: To verify treatment adherence and associated factors, as well as blood pressure (BP control in participants of the Resistant Hypertension Optimal Treatment (ReHOT clinical trial. Method: Cross-sectional study including all 109 patients who had completed the ReHOT for at least 6 months. We excluded those participants who failed to respond to the new recruitment after three phone contact attempts. We evaluated the BP control by ambulatory BP monitoring (ABPM; controlled levels: 24-hour systolic and diastolic BP < 130 x 80 mmHg and analyzed the patients' treatment adherence using the Morisky Medication Adherence Scale (MMAS questionnaire validated by Bloch, Melo, and Nogueira (2008. The statistical analysis was performed with the software IBM SPSS statistics 21.0. We tested the normality of the data distribution with kurtosis and skewness. The variables tested in the study are presented with descriptive statistics. Comparisons between treatment adherence and other variables were performed with Student's t test for independent variables and Pearson's chi-square or Fisher's exact test. To conduct analyses among patients considering adherence to treatment and BP control, we created four groups: G0, G1, G2, and G3. We considered a 5% significance level in all tests. Results: During the ReHOT, 80% of the patients had good BP control and treatment adherence. Of 96 patients reevaluated in the present study, only 52.1% had controlled hypertension when assessed by ABPM, while 31.3% were considered adherent by the MMAS. Regarding other ABPM measures, we observed an absence of a nocturnal dip in 64.6% of the patients and a white-coat effect and false BP control in 23% and 12.5%, respectively. Patients' education level showed a trend towards being a determinant factor associated with lack of adherence (p = 0 5. Effect of Furnish on Temperature and Vapor Pressure Behavior in the Center of Mat Panels during Hot Pressing Directory of Open Access Journals (Sweden) Muhammad Navis Rofii 2014-07-01 Full Text Available Particleboard achieves its overall performance characteristics during hot pressing process. As this process is influenced by several factors, particularly temperature and pressure, it is very important to understand the behavior of both. This study investigates the effects of furnish materials on temperature and vapor pressure behavior inside particleboard mat panels during hot pressing. Strand type particles from hinoki and ring-flaker recycled wood particles were used as furnish for laboratory-scale particleboard panels with a target density of 0.76 g/cm³. Mat panels with a moisture content of about 10% were hot pressed at a platen temperature of 180°C and an initial pressure of 3 MPa until the mat center reached the same temperature as the platen. A press monitoring device (PressMAN Lite was used for detecting the temperature and vapor pressure change in the center of the mat panels. The study showed that the furnish type affected the temperature and vapor behavior inside the mat panels. Particleboard made of hinoki strand resulted in a longer plateau time, a higher plateau temperature and a higher gas pressure generated during hot pressing than those of ring-flaker recycled wood particles. Mixed board resulted in values between those of the two other furnish materials. 6. Isostatic Model and Isostatic Gravity Anomalies of the Arabian Plate and Surroundings Science.gov (United States) Kaban, Mikhail K.; El Khrepy, Sami; Al-Arifi, Nassir 2016-04-01 The isostatic modeling represents one of the most useful "geological" reduction methods of the gravity field. With the isostatic correction, it is possible to remove a significant part of the effect of deep density heterogeneity, which dominates in the Bouguer gravity anomalies. Although there exist several isostatic compensation schemes, it is usually supposed that a choice of the model is not an important factor to first order, since the total weight of compensating masses remains the same. We compare two alternative models for the Arabian plate and surrounding area. The Airy model gives very significant regional isostatic anomalies, which cannot be explained by the upper crust structure or disturbances of the isostatic equilibrium. Also, the predicted "isostatic" Moho is very different from existing seismic observations. The second isostatic model includes the Moho, which is based on seismic determinations. Additional compensation is provided by density variations within the lithosphere (chiefly in the upper mantle). According to this model, the upper mantle under the Arabian Shield is less dense than under the Platform. In the Arabian platform, the maximum density coincides with the Rub' al Khali, one of the richest oil basin in the world. This finding agrees with previous studies, showing that such basins are often underlain by dense mantle, possibly related to an eclogite layer that has caused their subsidence. The mantle density variations might be also a result of variations of the lithosphere thickness. With the combined isostatic model, it is possible to minimize regional anomalies over the Arabian plate. The residual local anomalies correspond well to tectonic structure of the plate. Still very significant anomalies, showing isostatic disturbances of the lithosphere, are associated with the Zagros fold belt, the collision zone of the Arabian and Eurasian plates. 7. PRESSURE EQUILIBRIUM BETWEEN THE LOCAL INTERSTELLAR CLOUDS AND THE LOCAL HOT BUBBLE Energy Technology Data Exchange (ETDEWEB) Snowden, S. L.; Chiao, M.; Collier, M. R.; Porter, F. S.; Thomas, N. E. [NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Cravens, T.; Robertson, I. P. [Department of Physics and Astronomy, University of Kansas, 1251 Wescoe Hall Drive, Lawrence, KS 66045 (United States); Galeazzi, M.; Uprety, Y.; Ursino, E. [Department of Physics, University of Miami, 1320 Campo Sano Drive, Coral Gables, FL 33146 (United States); Koutroumpa, D. [Université Versailles St-Quentin, Sorbonne Universités, UPMC Univ. Paris 06, CNRS/INSU, LATMOS-IPSL, 11 Boulevard d' Alembert, F-78280 Guyancourt (France); Kuntz, K. D. [The Henry A. Rowland Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MD 21218 (United States); Lallement, R.; Puspitarini, L. [GEPI, Observatoire de Paris, CNRS UMR8111, Université Paris Diderot, 5 Place Jules Janssen, F-92190 Meudon (France); Lepri, S. T. [University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109 (United States); McCammon, D.; Morgan, K. [Department of Physics, University of Wisconsin, 1150 University Avenue, Madison, WI 53706 (United States); Walsh, B. M., E-mail: [email protected] [Space Sciences Laboratory, 7 Gauss Way, Berkeley, CA 94720 (United States) 2014-08-10 Three recent results related to the heliosphere and the local interstellar medium (ISM) have provided an improved insight into the distribution and conditions of material in the solar neighborhood. These are the measurement of the magnetic field outside of the heliosphere by Voyager 1, the improved mapping of the three-dimensional structure of neutral material surrounding the Local Cavity using extensive ISM absorption line and reddening data, and a sounding rocket flight which observed the heliospheric helium focusing cone in X-rays and provided a robust estimate of the contribution of solar wind charge exchange emission to the ROSAT All-Sky Survey 1/4 keV band data. Combining these disparate results, we show that the thermal pressure of the plasma in the Local Hot Bubble (LHB) is P/k = 10, 700 cm{sup –3} K. If the LHB is relatively free of a global magnetic field, it can easily be in pressure (thermal plus magnetic field) equilibrium with the local interstellar clouds, eliminating a long-standing discrepancy in models of the local ISM. 8. Relationship between hot flashes and ambulatory blood pressure: the Hilo women's health study. Science.gov (United States) Brown, Daniel E; Sievert, Lynnette L; Morrison, Lynn A; Rahberg, Nichole; Reza, Angela 2011-01-01 To examine ambulatory blood pressure (BP) differences between women who report hot flashes (HFs) and those who do not, and to observe whether an objectively measured HF is associated with transient changes in BP. HFs have been associated with elevated BP, but studies have not examined the relationship between objectively measured HFs and blood pressure during normal daily activities. A sample of 202 women in Hilo, Hawaii, aged 45 to 55 years, were asked to fill out a questionnaire that included demographic information and an inventory of symptoms. The women underwent simultaneous 24-hour monitoring of ambulatory BP and HFs, at the same time keeping a diary that included mood and HF reports. No significant difference was present in mean BP between women who reported having an HF during the last 2 weeks and those who did not. When measurements controlled for negative mood reports and posture, there was a highly significant elevation in Z scores of systolic BP when a measured, objective HF occurred within 10 minutes before a BP reading, and a significant elevation of Z scores of diastolic BP when a subjectively reported HF occurred within 10 minutes after a BP reading. These results suggest that objectively measured HFs precede transient elevations of systolic BP, but it is unclear if there is a causal relationship. These results also suggest that women experience subjective HFs within 10 minutes after a transient increase in diastolic BP. Again, the causal relationship is not understood. 9. A comparison of disturbance levels measured in hypersonic tunnels using a hot-wire anemometer and a pitot pressure probe. Science.gov (United States) Stainback, P. C.; Wagner, R. D. 1972-01-01 Disturbance levels were measured in the test section of a Mach 5 blowdown jet using a constant-current, hot-wire anemometer and a pressure transducer. The disturbance levels, measured by the two instruments and normalized by local mean values, agreed within about 30%, with the pitot data higher than the hot-wire data. The rms disturbance levels measured with the hot-wire anemometer and converted to pitot pressures using a quasi-steady flow analysis, were about two-thirds the levels measured with the pitot probe. The variation of the normalized rms disturbance levels with stagnation pressure indicated that transition occurred in the boundary layer on the nozzle wall and influenced the outputs of the instruments located at the exit of the nozzle when the total pressure was about 35 N/sq cm. Below this pressure the disturbance levels decreased markedly. At higher pressures the disturbances were predominantly aerodynamic noise generated by the turbulent boundary layer on the nozzle wall. 10. Results of intermediate-scale hot isostatic press can experiments International Nuclear Information System (INIS) Nelson, L.O.; Vinjamuri, K. 1995-05-01 Radioactive high-level waste (HLW) has been managed at the Idaho Chemical Processing Plant (ICPP) for a number of years. Since 1963, liquid HLW has been solidified into a granular solid (calcine). Presently, over 3,800 m 3 of calcine is stored in partially-underground stainless steel bins. Four intermediate- scale HLW can tests (two 6-in OD x 12-in tall and two 4-in OD x 7-in tall) are described and compared to small-scale HIP can tests (1- to 3-in OD x 1- to 4.5-in tall). The intermediate-scale HIP cans were loaded with a 70/30 calcine/frit blend and HIPped at an off-site facility at 1050 degrees C; and 20 ksi. The dimensions of two cans (4-in OD x 7-in tall) were monitored during the HIP cycle with eddy-current sensors. The sensor measurements indicated that can deformation occurs rapidly at 700 degrees C; after which, there is little additional can shrinkage. HIP cans were subjected to a number of analyses including calculation of the overall packing efficiency (56 to 59%), measurement of glass-ceramic (3.0 to 3.2 g/cc), 14-day MCC-1 leach testing (total mass loss rates 2 day), and scanning electron microscopy (SEM). Based on these analyses, the glass-ceramic material produced in intermediate-scale cans is similar to material produced in small-scale cans. No major scale-up problems were indicated. Based on the packing efficiency observed in intermediate- and small-scale tests, the overall packing efficiency of production-scale (24-in OD x 36- to 190-in tall) cans would be approximately 64% for a pre-HIP right-circular cylinder geometry. An efficiency of 64% would represent a volume reduction factor of 2.5 over a candidate glass waste prepared at 33 wt% waste loading 11. Development of Hot Isostatically Pressed Rene 95 Turbine Parts Science.gov (United States) 1977-05-01 Jull 17 ,. " 1ENE’ 95 TURBINE PARTS~ 7. AUTHOR(e) CO(A RRNNME P.)Mathur aWJ. Bartos AJ-3C0V hae1 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM...200 mesh coff .,acts prepared in the autoclave at 20500F and the -60 mesh compact prepared by 1650 0F14 hours, 2000°1/1 hour/OQ, + 1400°F/16 hours/AC...Product Acceptance plans (Appendix- Ill); the Quality Control of General Elctric Company was-extended to establish procedures and- organization , to 12. Idaho Batholith Study Area Isostatic Gravity Grid Data.gov (United States) National Oceanic and Atmospheric Administration, Department of Commerce — A 2 kilometer isostatic gravity grid for the Idaho batholith study area. Number of columns is 331 and number of rows is 285. The order of the data is from the lower... 13. Comparison of various isostatic marine gravity disturbances Indian Academy of Sciences (India) due to the fact that the same isostatic principle is applied in both these definitions expect for assuming a local (in the ..... Gladkikh V and Tenzer R 2011 A mathematical model of the ... and its Gravity Field; McGraw-Hill Book Company, Inc. 14. Hot gas cleanup test facility for gasification and pressurized combustion. Quarterly technical progress report, July 1--September 30, 1992 Energy Technology Data Exchange (ETDEWEB) 1992-12-31 The objective of this project is to evaluate hot gas particle control technologies using coal-derived gas streams. This will entail the design, construction, installation, and use of a flexible test facility which can operate under realistic gasification and combustion conditions. The major particulate control device issues to be addressed include the integration of the particulate control devices into coal utilization systems, on-line cleaning techniques, chemical and thermal degradation of components, fatigue or structural failures, blinding, collection efficiency as a function of particle size, and scale-up of particulate control systems to commercial size. The conceptual design of the facility was extended to include a within scope, phased expansion of the existing Hot Gas Cleanup Test Facility Cooperative Agreement to also address systems integration issues of hot particulate removal in advanced coal-based power generation systems. This expansion included the consideration of the following modules at the test facility in addition to the existing Transport Reactor gas source and Hot Gas Cleanup Units: Carbonizer/Pressurized Circulating Fluidized Bed Gas Source; hot Gas Cleanup Units to mate to all gas streams; and Combustion Gas Turbine. Fuel Cell and associated gas treatment. This expansion to the Hot Gas Cleanup Test Facility is herein referred to as the Power Systems Development Facility (PSDF). 15. Tubular heat exchangers, preferably for hot ashes and the like with two inlet chambers for hot ashes at different pressures Energy Technology Data Exchange (ETDEWEB) Vasiliev, B P; Borisov, N L; Semenov, M K; Ponomarev, I K; Tyryshkina, B G; Gorbatenko, I V 1985-10-28 The stand and the tubes are encased in a structure where the space between the stand and the structure is divided into a collector chamber and a distribution chamber. Ashes of shale are introduced at different pressures into a special inlet where equalizing takes place and the ashes will flow homogeneously through the heat exchanger. 16. Isostatic models and isostatic gravity anomalies of the Arabian plate and surroundings Science.gov (United States) Kaban, Mikhail K.; El Khrepy, Sami; Al-Arifi, Nassir 2015-04-01 Isostaic anomalies represent one of the most useful "geological" reduction of the gravity field. With the isostatic correction it is possible to remove a significant part of the effect of deep density heterogeneity, which dominates in the Bouguer gravity anomalies. This correction is based on the fact that a major part of the near-surface load is compensated by variations of the lithosphere boundaries (chiefly the Moho and LAB) and by density variations within the crust and upper mantle. It is usually supposed that it is less important to a first order, what is the actual compensation model when reducing the effect of compensating masses, since their total weight is exactly opposite to the near-surface load. We compare several compensating models for the Arabian plate and surrounding area. The Airy model gives very significant regional isostatic anomalies, which can not be explained by the upper crust structure or disturbances of the isostatic equilibrium. Also the predicted "isostatic" Moho is very different from the existing observations. The second group of the isostatic models includes the Moho, which is based on existing seismic determinations. Additional compensation is provided by density variations within the lithosphere (chiefly in the upper mantle). In this way we minimize regional anomalies over the Arabian plate. The residual local anomalies well correspond to tectonic structure of the plate. Still very significant anomalies are associated with the Zagros fold belt, the collision zone of the Arabian and Eurasian plates. 17. Numerical study of hot-leg ECC injection into the upper plenum of a pressurized water reactor International Nuclear Information System (INIS) Daly, B.J.; Torrey, M.D.; Rivard, W.C. 1981-01-01 In certain pressurized water reactor (PWR) designs, emergency core coolant (ECC) is injected through the hot legs into the upper plenum. The condensation of steam on this subcooled liquid stream reduces the pressure in the hot legs and upper plenum and thereby affects flow conditions throughout the reactor. In the present study, we examine countercurrent steam-water flow in the hot leg to determine the deceleration of the ECC flow that results from an adverse pressure gradient and from momentum exchange from the steam by interfacial drag and condensation. For the parameters examined in the study, water flow reversal is observed for a pressure drop of 22 to 32 mBar over the 1.5 m hot leg. We have also performed a three-dimensional study of subcooled water injection into air and steam environments of the upper plenum. The ECC water is deflected by an array of cylindrical guide tubes in its passage through the upper plenum. Comparisons of the air-water results with data obtained in a full scale experiment shows reasonable agreement, but indicates that there may be too much resistance to horizontal flow about the columns because of the use of a stair-step representation of the cylindrical guide tube cross section. Calculations of flow past single columns of stair-step, square and circular cross section do indicate excessive water deeentrainment by the noncircular column. This has prompted the use of an arbitrary mesh computational procedure to more accuratey represent the circular cross-section guide tubes. 15 figures 18. Comparison between uniaxially and isostatically compacted bentonite International Nuclear Information System (INIS) Kalbantner, P.; Sjoeblom, R.; Boergesson, Lennart 2001-12-01 The purpose of the present report is to provide the Swedish Nuclear Fuel and Waste Management Company (SKB) with the knowledge base needed for their selection of reference method for manufacturing of bentonite blocks. The purpose is also to provide support for the direction of the further development work. Three types of blocks are compared in the present report: uniaxially compacted medium high blocks, isostatically compacted medium high blocks, isostatically compacted high blocks. The analyses is based on three process systems relating to the sequence of excavation of bentonite-transport-powder preparation-compaction-handling and emplacement of bentonite blocks. The need for further knowledge has been identified and documented in conjunction with these analyses. The comparison is primarily made with regard to the criteria safety/risk, quality/ technique and economy. It is carried out through identification of issues of significance and subsequent analysis and evaluation as well as more formally in a simplified AHP (AHP = Analytical Hierarchic Process). The result of the analyses is that the isostatic technique is applicable for the production of high as well as medium size blocks. The pressed blocks are assessed to fulfil the basic requirements with a very large margin. The result of the analyses is also that the uniaxial technique is applicable for the preparation of medium size blocks, which are assessed to fulfil the basic requirements with a large margin. The need for development and process control is assessed to be somewhat higher for the uniaxial technique. One example is the friction against the walls of the die during the compaction, including the significance of this friction for the development of stresses and discontinuities in the block. These results support a selection of the isostatic technique as the reference technique as it provides flexibility in the choice of block height. The uniaxial technique can form a second alternative if medium high 19. Data from Sustainability Base Characterizing Hot Water Pump Differential Pressure Spikes for ACCEPT Data.gov (United States) National Aeronautics and Space Administration — During the heating season in Sustainability Base, a critical alarm associated with a hot water pump circulating heating water for the radiative system which... 20. Isostatic model for the Tharsis province, Mars International Nuclear Information System (INIS) Sleep, N.H.; Phillips, R.J. 1979-01-01 A crust-upper mantle configuration is proposed for the Tharsis province of Mars which is isostatic and satisfies the observed gravity data. The model is that of a low density upper mantle compensating loads at both the surface and crust-mantle boundary. Solutions are found for lithospheric thickness greater than about 300 km, for which the stress differences are less than 750 bars. This model for Tharsis is similar to the compensation mechanism under the Basin and Range province of the western United States. These provinces also compare favorably in the sense that they are both elevated regions of extensional tectonics and extensive volcanism 1. Scaling of Pressure with Intensity in Laser-Driven Shocks and Effects of Hot X-Ray Preheat International Nuclear Information System (INIS) Colvin, Jeffrey D.; Kalantar, Daniel H. 2006-01-01 To drive shocks into solids with a laser we either illuminate the material directly, or to get higher pressures, illuminate a plastic ablator that overlays the material of interest. In both cases the illumination intensity is low, <<1013 W/cm2, compared to that for traditional laser fusion targets. In this regime, the laser beam creates and interacts with a collisional, rather than a collisionless, plasma. We present scaling relationships for shock pressure with intensity derived from simulations for this low-intensity collisional plasma regime. In addition, sometimes the plastic-ablator targets have a thin flash-coating of Al on the plastic surface as a shine-through barrier; this Al layer can be a source of hot x-ray preheat. We discuss how the preheat affects the shock pressure, with application to simulating VISAR measurements from experiments conducted on various lasers on shock compression of Fe 2. Scaling of Pressure with Intensity in Laser-Driven Shocks and Effects of Hot X-ray Preheat International Nuclear Information System (INIS) Colvin, J D; Kalantar, D H 2005-01-01 To drive shocks into solids with a laser we either illuminate the material directly, or to get higher pressures, illuminate a plastic ablator that overlays the material of interest. In both cases the illumination intensity is low, 13 W/cm 2 , compared to that for traditional laser fusion targets. In this regime, the laser beam creates and interacts with a collisional, rather than a collisionless, plasma. We present scaling relationships for shock pressure with intensity derived from simulations for this low-intensity collisional plasma regime. In addition, sometimes the plastic-ablator targets have a thin flashcoating of Al on the plastic surface as a shine-through barrier; this Al layer can be a source of hot x-ray preheat. We discuss how the preheat affects the shock pressure, with application to simulating VISAR measurements from experiments conducted on various lasers on shock compression of Fe 3. Properties of hot pressed MgB2/Ti tapes International Nuclear Information System (INIS) Kovac, P.; Husek, I.; Melisek, T.; Fedor, J.; Cambel, V.; Morawski, A.; Kario, A. 2009-01-01 Hot axial and hot isostatic pressing was applied for single-core MgB 2 /Ti tapes. Differences in transport current density, n-exponents and critical current anisotropy are discussed and related to the grain connectivity influenced by pressing. The magnetic Hall probe scanning measurements allowed observing the isolated regions for axially hot pressed sample attributed to the longitudinally oriented cracks introduced by pressing. The highest current densities were measured for the tape subjected to hot isostatic pressing due to improved connectivity. 4. 2.5-min Isostatic Gravity Grid for the United States Data.gov (United States) National Oceanic and Atmospheric Administration, Department of Commerce — The 2.5-min isostatic gravity data set was produced by regridding the 4-km residual isostatic gravity grid of the U.S. The isostatic residual gravity grid was... 5. Hot cell examination on the surveillance capsule of SA 533 cl. 1 reactor pressure vessel (1st test report) Energy Technology Data Exchange (ETDEWEB) Choo, Yong Sun; Jung, Y. H.; Yoo, B. O.; Baik, S. J.; Oh, W. H.; Soong, W. S.; Hong, K. P 2000-08-01 The post-irradiated examinations such as impact test, tensile test, composition analysis and etc. were conducted to monitor and to evaluate the radiation-induced changes, so called radiation embrittlement, in the mechanical properties of ferritic materials. Those data should be applied to confirm safety as well as reliability of reactor pressure vessel. The scopes and contents of hot cell examination on the surveillance capsule are as follows; - Capsule transportation, cutting, dismantling and classification - Shim block and Dosimeter cutting and dismantling - Impact test - Tensile test - Composition analysis by EPMA - SEM observation on the fractured surface - Hardness test - Radwaste treatment. 6. Treatment of zircaloy cladding hulls by isostatic pressing International Nuclear Information System (INIS) Tegman, R.; Burstroem, M. 1984-12-01 A method for the treatment of Zircaloy fuel hulls is proposed. It involves hot isostatic pressing (HIP) for making large, completely densified metallic bodies of the waste. The hulls are packed into a bellows-shaped container of steel. On packing the fuel hulls give a filling factor of only 14%, which is too low for non-deformable compaction in a normal container, but by using a belloped container, a non-deformable compaction can be obtained without any pretreatment of the hulls. Fully dense and mechanically strong blocks of Zircaloy can be fabricated by holding them at temperatures of around 1000 degrees C for three hours. It is also feasible to incorporate the other metallic parts of the fuel bundle, such as top and bottom tie plates and spacers, in the pressing. The HIP-densified hulls provide an effective means of self-containment of radioactive waste due to the excellent corrosion resistance of Zircaloy. A waste loading factor of close to 100% can be realized. Futher, a volume reduction factor of 7 and a surface reduction factor of aout 250 for a 1-ton canister can be achieved. Equilibrium calculations have shown that tritium present in the hulls can quantitatively be contained in the HIPed block. A study has been made of a possible process for industrilscale use. (Author) 7. Elution behavior into the high pressured hot water and the organizational change of granite and andesite Energy Technology Data Exchange (ETDEWEB) Matsunaga, Isao; Miyazaki, Akira; Yamaguchi, Tsutomu; kuriyakawa, Michio 1988-04-01 In the development of a high temperature rock system, the interaction between the rock and hot water which occurs in a reservoir provides big effects. The decline of the strength and the increase of the permeability are caused by the elusion of the rock on the surface of the hydraulic fracture and the redeposition of the eluded material also causes to narrow or close the channel. However, studies concerning the organizational change of the rock by the hot water or the material change associated with the organizational change are small in number. In this research, Inaba granite and Honkomatsu andesite were treated in heat with an autoclave in order to investigate the organizational changes of the rocks and at the same time, the elusion behavior of the rocks into the hot water was investigated by examining chemical components which were eluded into the fluid and the components remaining on the rock surface. The decreased amount per specific surface area due to the autoclave treatment is the order of 10/sup -3/(gcm/sup -2/) for both rocks and changeable depending upon the heating temperature and the kind of rock. As a result of the analysis of the fluids in the autoclave after the heat treatment, the Si concentration of Honkomatsu andesite was higher in the same temperature and the heating time. (2 figs, 3 tabs, 6 refs) 8. MANU. Isostatic compression of buffer blocks. Small scale International Nuclear Information System (INIS) Laaksonen, R. 2010-01-01 The purpose of this study was to become familiar with the isostatic compression technique and to manufacture specimens to study various aspects of the manufacturing process. These included for example the effect of moisture, maximum compressive pressure, vibration, vacuum, specimen size, coating, multiple compressions and duration of load cycle on the density and other properties of bentonite specimens. Also the amount of volumetric contraction was of interest in this study together with the used mould technology. This work summarizes the tests done with isostatic compression technique during 2008. Tests were mainly carried out with MX-80 bentonite, which is a commercial product and currently the reference bentonite in the repository reference plan. Tests were made from June to November 2008 both in Finland and in Sweden. VTT made four test series in Finland. MABU Consulting Ab made two test series in Sweden. Also Posiva Oy carried out one preliminary series before this study in Finland. The test results show that there is a clear relationship between density and moisture content at all pressure levels. The calculated degree of saturation of more moist samples remained at the level of 95 -to 98 % of full saturation. It should be possible to manufacture buffer blocks with high accuracy (density, water content, degree of saturation), if similar preliminary tests are done. Tests did not support the assumption that vacuum (partial or full) in the specimen during compression increases the final density. Tests showed that pre-vibrated specimens had a slightly higher density but the difference was insignificant. Coarse raw bentonite produced the highest dry density of all sodium bentonites used. The highest dry density values were received with Minelco's Ca-bentonite, but the average water content was not extremely accurate. The following recommendations were derived from the results of this project: additional tests should be carried out to determine the relationship 9. High pressure low temperature hot pressing method for producing a zirconium carbide ceramic Science.gov (United States) Cockeram, Brian V. 2017-01-10 A method for producing monolithic Zirconium Carbide (ZrC) is described. The method includes raising a pressure applied to a ZrC powder until a final pressure of greater than 40 MPa is reached; and raising a temperature of the ZrC powder until a final temperature of less than 2200.degree. C. is reached. 10. High pressure processing with hot sauce flavoring enhances sensory quality for raw oysters (Crassostrea virginica) Science.gov (United States) This study evaluated the feasibility of flavoring raw oysters by placing them under pressure in the presence of selected flavorings. Hand-shucked raw oysters were processed at high pressure (600 MPa), in the presence or absence of (Sriracha®) flavoring, and evaluated by a trained sensory panel 3 an... 11. Uncertainty in Greenland glacial isostatic adjustment DEFF Research Database (Denmark) Milne, G. A.; Lecavalier, B.; Kjeldsen, K. K. It is well known that the interpretation of geodetic data in Greenland to constrain recent ice mass changes requires knowledge of isostatic land motion associated with past changes in the ice sheet. In this talk we will consider a variety of factors that limit how well the signal due to past mass...... of the GIA model on predictions of land motion and gravity changes. The sensitivity of model output to plausible variations in both depth-dependent and lateral viscosity structure will be considered. With respect to the ice model, we will compare the relative contributions of loading during key periods...... of the ice history with a focus on the past few thousand years. In particular, we will show predictions of contemporary land motion and gravity changes due to loading changes following the Little Ice Age computed using a new reconstruction of ice thickness changes based largely on empirical data. A primary... 12. Isostatic models and isostatic gravity anomalies of the Arabian plate and surroundings OpenAIRE M. K. Kaban; Sami El Khrepy; Nassir Al-Arifi 2015-01-01 Isostaic anomalies represent one of the most useful “geological” reduction of the gravity field. With the isostatic correction it is possible to remove a significant part of the effect of deep density heterogeneity, which dominates in the Bouguer gravity anomalies. This correction is based on the fact that a major part of the near-surface load is compensated by variations of the lithosphere boundaries (chiefly the Moho and LAB) and by density variations within the crust and upper man... 13. Improvement of the Water Resistance of a Narrow-Band Red-Emitting SrLiAl3 N4 :Eu(2+) Phosphor Synthesized under High Isostatic Pressure through Coating with an Organosilica Layer. Science.gov (United States) Tsai, Yi-Ting; Nguyen, Hoang-Duy; Lazarowska, Agata; Mahlik, Sebastian; Grinberg, Marek; Liu, Ru-Shi 2016-08-08 A SrLiAl3 N4 :Eu(2+) (SLA) red phosphor prepared through a high-pressure solid-state reaction was coated with an organosilica layer with a thickness of 400-600 nm to improve its water resistance. The observed 4f(6) 5d→4f(7) transition bands are thought to result from the existence of Eu(2+) at two different Sr(2+) sites. Luminescence spectra at 10 K revealed two zero-phonon lines at 15377 (for Eu(Sr1)) and 15780 cm(-1) (for Eu(Sr2)). The phosphor exhibited stable red emission under high pressure up to 312 kbar. The configurational coordinate diagram gave a theoretical explanation for the Eu(2+/3+) result. The coated samples showed excellent moisture resistance while retaining an external quantum efficiency (EQE) of 70 % of their initial EQE after aging for 5 days under harsh conditions. White-light-emitting diodes of the SLA red phosphor and a commercial Y3 Al5 O12 :Ce(3+) yellow phosphor on a blue InGaN chip showed high color rendition (CRI=89, R9=69) and a low correlated color temperature of 2406 K. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. 14. Utilisation of heat and pressure through the whole fuel cycle International Nuclear Information System (INIS) Eddowes, T.; Moricca, S.; Webb, N. 2003-01-01 Full text: The existence of the earth around us is a result of heat and pressure combined to form the very crust we stand on. With such a good model, scientists working throughout the nuclear fuel cycle have used these principles to optimise each particular step. From the fabrication of fuel rods and running of reactors to the final storage of the waste generated; heat and pressure have proved to be vital resources. At ANSTO the concepts of using heat and pressure to consolidate the waste produced for the nuclear fuel cycle have been extensively investigated. Working with collaborators, it has been demonstrated that the intermediate to high level waste can be incorporated into a ceramic or glass-ceramic matrix and immobilised therein, using heat and pressure via the means of a Hot Isostatic Press. This paper touches on how following the simple principles of heat and pressure utilised in the operation of this planet every day, the nuclear fuel cycle can be most efficient. The main focus has been the utilisation of Hot Isostatic Pressing for the production of various durable wasteforms at ANSTO for both Australian and international wastes 15. Gas hydrate dissociation off Svalbard induced by isostatic rebound rather than global warming. Science.gov (United States) Wallmann, Klaus; Riedel, M; Hong, W L; Patton, H; Hubbard, A; Pape, T; Hsu, C W; Schmidt, C; Johnson, J E; Torres, M E; Andreassen, K; Berndt, C; Bohrmann, G 2018-01-08 Methane seepage from the upper continental slopes of Western Svalbard has previously been attributed to gas hydrate dissociation induced by anthropogenic warming of ambient bottom waters. Here we show that sediment cores drilled off Prins Karls Foreland contain freshwater from dissociating hydrates. However, our modeling indicates that the observed pore water freshening began around 8 ka BP when the rate of isostatic uplift outpaced eustatic sea-level rise. The resultant local shallowing and lowering of hydrostatic pressure forced gas hydrate dissociation and dissolved chloride depletions consistent with our geochemical analysis. Hence, we propose that hydrate dissociation was triggered by postglacial isostatic rebound rather than anthropogenic warming. Furthermore, we show that methane fluxes from dissociating hydrates were considerably smaller than present methane seepage rates implying that gas hydrates were not a major source of methane to the oceans, but rather acted as a dynamic seal, regulating methane release from deep geological reservoirs. 16. Pressurized thermal shock. CNA-I behavior when a hot leg breaks of 50 cm2 is produced International Nuclear Information System (INIS) Rosso, Ricardo D.; Ventura, Mirta A. 2002-01-01 Pressurized thermal shock (PTS) phenomena in the CNA-I pressurize heavy water reactor is analyzed in this paper. The initiating event is a hypothetical 50 cm 2 break of the line connecting the pressurizer and the primary system. The calculation procedure for obtaining the local thermal-hydraulic parameters in the reactor pressure vessel downcomer is described firstly. Results obtained lead to conclusions in different subjects. The first conclusion is that a simple tool of easy application is available to analyze PTS phenomena in cases of breaks in the primary system in cold and hot legs. This methodology is fully independent of the methodology utilized by the Utility. Another important conclusion comes from the analysis of the temperature evolution of the fluid below the cold leg level in the RPV downcomer, as a function of the T HPI temperature of the TJ system injected water from. It is also concluded that the results obtained with the methodology adopted agree with the ones obtained with the methodologies validated against experiments in the UPTF facility. It is possible to observe that when T HPI increase, the conditions suitable for PTS occurrence in a LOCA accident tend to diminish. The maximum value to the T HPI may be fixed from the maximum temperature allowed to preserve the structural integrity of the fuel cladding. (author) 17. Early response of pressurized hot water in a pipe to a sudden break. Final report International Nuclear Information System (INIS) Alamgir, M.; Kan, C.Y.; Lienhard, J.H. 1981-06-01 Experimental and analytic studies that explain the details of early pressure variations during rapid depressurization in water-cooled reactors are presented as a means of assessing sudden break consequences in a coolant pipe. The report includes (1) a description of the experiment, (2) an analysis of the new bubble growth law for thermally controlled growth of vapor bubbles in an exponentially-varying pressure field, and (3) a review of previous studies and additional observations of blowdown behavior 18. Numerical Investigation on the Influence of Hot Streak Temperature Ratio in a High-Pressure Stage of Vaneless Counter-Rotating Turbine Directory of Open Access Journals (Sweden) Zhao Qingjun 2007-01-01 Full Text Available The results of recent studies have shown that combustor exit temperature distortion can cause excessive heat load of high-pressure turbine (HPT rotor blades. The heating of HPT rotor blades can lead to thermal fatigue and degrade turbine performance. In order to explore the influence of hot streak temperature ratio on the temperature distributions of HPT airfoil surface, three-dimensional multiblade row unsteady Navier-Stokes simulations have been performed in a vaneless counter-rotating turbine (VCRT. The hot streak temperature ratios from 1.0 (without hot streak to 2.4 were used in these numerical simulations, including 1.0, 1.2, 1.6, 2.0, and 2.4 temperature ratios. The hot streak is circular in shape with a diameter equal to 25% of the span. The center of the hot streak is located at 50% of span and 0% of pitch (the leading edge of the HPT stator vane. The predicted results show that the hot streak is relatively unaffected as it migrates through the HPT stator. The hot streak mixes with the vane wake and convects towards the pressure surface (PS of the HPT rotor when it moves over the vane surface of the HPT stator. The heat load of the HPT rotor increases with the increase of the hot streak temperature ratio. The existence of the inlet temperature distortion induces a thin layer of cooler air in the HPT rotor, which separates the PS of the HPT rotor from the hotter fluid. The numerical results also indicating the migration characteristics of the hot streak in the HPT rotor are predominated by the combined effects of secondary flow and buoyancy. The combined effects that induce the high-temperature fluid migrate towards the hub on the HPT rotor. The effect of the secondary flow on the hotter fluid increases as the hot streak temperature ratio is increased. The influence of buoyancy is directly proportional to the hot streak temperature ratio. The predicted results show that the increase of the hot streak temperature ratio trends to increase 19. Performance of carbon-based hot frit substrates: I, Low pressure helium and hydrogen testing International Nuclear Information System (INIS) Barletta, R.; Adams, J.; Svandrlik, J.; Powell, J.R. 1993-07-01 The performance of various carbon-based materials in flowing, high-temperature helium and hydrogen is described. These materials which are candidate hot frit substrates for possible application in a PBR include various grades of graphite, carbon-carbon and vitreous carbon. Vitreous carbon showed extremely good performance in helium, while that of the various graphite grades was quite variable and, in some cases, poor. Purified grades performed better than unpurified grades, but in all cases large sample-to-sample variations in weight loss were observed. For carbon-carbon samples, the performance was intermediate. Since the weight loss in these samples was in large measure due to the loss of the densification media, improvements in the performance of carbon-carbon may be possible. With respect to the performance in hydrogen, high weight losses were observed, re-enforcing the need for coating carbon-based materials for service in a flowing hydrogen environment 20. Demonstration of Fuel Hot-Spot Pressure in Excess of 50 Gbar for Direct-Drive, Layered Deuterium-Tritium Implosions on OMEGA Science.gov (United States) Regan, S. P.; Goncharov, V. N.; Igumenshchev, I. V.; Sangster, T. C.; Betti, R.; Bose, A.; Boehly, T. R.; Bonino, M. J.; Campbell, E. M.; Cao, D.; Collins, T. J. B.; Craxton, R. S.; Davis, A. K.; Delettrez, J. A.; Edgell, D. H.; Epstein, R.; Forrest, C. J.; Frenje, J. A.; Froula, D. H.; Gatu Johnson, M.; Glebov, V. Yu.; Harding, D. R.; Hohenberger, M.; Hu, S. X.; Jacobs-Perkins, D.; Janezic, R.; Karasik, M.; Keck, R. L.; Kelly, J. H.; Kessler, T. J.; Knauer, J. P.; Kosc, T. Z.; Loucks, S. J.; Marozas, J. A.; Marshall, F. J.; McCrory, R. L.; McKenty, P. W.; Meyerhofer, D. D.; Michel, D. T.; Myatt, J. F.; Obenschain, S. P.; Petrasso, R. D.; Radha, P. B.; Rice, B.; Rosenberg, M. J.; Schmitt, A. J.; Schmitt, M. J.; Seka, W.; Shmayda, W. T.; Shoup, M. J.; Shvydky, A.; Skupsky, S.; Solodov, A. A.; Stoeckl, C.; Theobald, W.; Ulreich, J.; Wittman, M. D.; Woo, K. M.; Yaakobi, B.; Zuegel, J. D. 2016-07-01 A record fuel hot-spot pressure Phs=56 ±7 Gbar was inferred from x-ray and nuclear diagnostics for direct-drive inertial confinement fusion cryogenic, layered deuterium-tritium implosions on the 60-beam, 30-kJ, 351-nm OMEGA Laser System. When hydrodynamically scaled to the energy of the National Ignition Facility, these implosions achieved a Lawson parameter ˜60 % of the value required for ignition [A. Bose et al., Phys. Rev. E 93, LM15119ER (2016)], similar to indirect-drive implosions [R. Betti et al., Phys. Rev. Lett. 114, 255003 (2015)], and nearly half of the direct-drive ignition-threshold pressure. Relative to symmetric, one-dimensional simulations, the inferred hot-spot pressure is approximately 40% lower. Three-dimensional simulations suggest that low-mode distortion of the hot spot seeded by laser-drive nonuniformity and target-positioning error reduces target performance. 1. High-Pressure Hot-Gas Self-Acting Floating Ring Shaft Seal for Liquid Rocket Turbopumps. [tapered bore seals Science.gov (United States) Burcham, R. E.; Diamond, W. A. 1980-01-01 Design analysis, detail design, fabrication, and experimental evaluation was performed on two self acting floating ring shaft seals for a rocket engine turbopump high pressure 24132500 n/sq m (3500 psig) hot gas 533 K 9500 F) high speed 3142 rad/sec (30000 rmp) turbine. The initial design used Rayleigh step hydrodynamic lift pads to assist in centering the seal ring with minimum rubbing contact. The final design used a convergent tapered bore to provide hydrostatic centering force. The Rayleigh step design was tested for 107 starts and 4.52 hours total. The leakage was satisfactory; however, the design was not acceptable due to excessive wear caused by inadequate centering force and failure of the sealing dam caused by erosion damage. The tapered bore design was tested for 370 starts and 15.93 hours total. Satisfactory performance for the required life of 7.5 hours per seal was successfully demonstrated. 2. Composition and crystallinity of silicon nanoparticles synthesised by hot wire thermal catalytic pyrolysis at different pressures CSIR Research Space (South Africa) Scriba, MR 2009-04-01 Full Text Available , whereas those produced at higher pressure are typically 50 nm. High resolution transmission electron microscopy (HR-TEM) shows a surface layer of between 2 and 5 nm thickness, which was confirmed by X-ray photoemission spectroscopy to be an oxide shell... 3. Industrial production of insulators using isostatic compaction method Energy Technology Data Exchange (ETDEWEB) Drugoveiko, O.P.; Ermolaeva, L.V.; Koren' , M.G.; Kreimer, B.D.; Panichev, G.I.; Ponomarev, A.P.; Rutkovskii, V.N. 1985-07-01 The process of shaping ceramic products from powders using isostatic compaction method is finding increasing industrial application. The production of electrical-engineering porcelain using isostatic compaction method is, according to the authors, a promising direction since this method permits one to obtain large and complex shaped products having uniform density distribution. The authors introduce an automatic isostatic compaction line at the ''Proletarii'' Factory for the production of the IOS-110-20000UKhL, T1 type insulators having the described dimensions. According to the technological process developed at the ''Elektrokeramika'' Production Complex, insulators were manufactured on the isostatic compaction line from the G-33 mass. Presspowder having a moisture content of 0.3-0.6% and a particle size of 90-160 micrometers was obtained in a spray dryer using disk spraying. The authors studied saturability by moisture of the powder obtained. 4. Finite element concept to derive isostatic residual maps ... Indian Academy of Sciences (India) A new space-domain operator based on the shape function concept of finite element analysis has been developed to derive the ... not require explicit assumptions on isostatic models. Besides .... This information is implicit in the Bouguer ... 5. Studies on micro-structures at vapor-liquid interfaces of film boiling on hot liquid surface at arriving of a shock pressure Energy Technology Data Exchange (ETDEWEB) Inoue, Akira; Lee, S. [Tokyo Inst. of Tech. (Japan) 1998-01-01 In vapor explosions, a pressure wave (shock wave) plays a fundamental role in the generation, propagation and escalation of the explosion. Transient volume change by rapid heat flow from a high temperature liquid to a low temperature volatile one and phase change generate micro-scale flow and the pressure wave. One of key issues for the vapor explosion is to make clear the mechanism to support the explosive energy release from hot drop to cold liquid. According to our observations by an Image Converter Camera, growth rate of vapor film around a hot tin drop became several times higher than that around a hot Platinum tube at the same conditions when a pressure pulse collapsed the film. The thermally induced fragmentation was followed by the explosive growth rate of the hot drop. In the previous report, we have proposed that the interface instability and fragmentation model in which the fine Taylor instability of vapor-liquid interface at the collapsing and re-growth phase of vapor film and the instability induced by the high pressure spots at the drop surface were assumed. In this study, the behavior of the vapor-liquid interface region at arrival of a pressure pulse was investigated by the CIPRIS code which is able to simulate dynamics of transient multi-phase interface regions. It is compared with the observation results. Through detailed investigations of these results, the mechanisms of the thermal fragmentation of single drop are discussed. (J.P.N.) 6. How deep, how hot: comparing pressure and temperature estimates from amphibole and rhyolite-MELTS thermobarometry Science.gov (United States) Pamukcu, A. S.; Gualda, G. A. 2013-12-01 Accurately constraining the pressure and temperature of magma residence is problematic, but it is key to understanding the structure and evolution of magmatic systems. Various thermometers exist (Fe-Ti oxides, Ti-in-zircon, Zr-in-sphene, etc.), but there are fewer barometers that can be applied to volcanic rocks. Most barometers capitalize on amphibole, a relatively common mineral whose composition is sensitive to pressure and temperature changes. Glass composition is a function of pressure for magmas saturated in quartz and feldspar, and a new thermobarometer based on rhyolite-MELTS simulations using glass (matrix glass and crystal-hosted glass inclusions) compositions has been recently proposed. We compare results from amphibole and matrix glass thermobarometry. We focus on outflow high-silica rhyolite pumice from the Peach Spring Tuff (CA-NV-AZ, USA), which are characterized by sanidine+plagioclase×quartz+amphibole+sphene in a high-silica rhyolite glass matrix. Compositional variations in amphibole are slight and described by edenite and Ti-Tschermak substitution, with little Al-Tschermak substitution, suggesting small changes in temperature but not in pressure. Plagioclase compositions are also nearly homogeneous. Thus, we expect thermobarometry results to cluster around a single pressure and temperature, making these samples excellent candidates for comparing thermobarometers. Amphibole×plagioclase thermobarometry reveals: - Amphibole-plagioclase: results vary widely depending on the calibration (e.g. 150-420 MPa, 520-730 °C); combined Anderson & Smith (1995) barometer with Holland & Blundy (1990) thermometer is most consistent, suggesting crystallization at 230 MPa, 680 °C. - Amphibole-only: calibrations give significantly different results (75-115 MPa, 770-960 °C [Ridolfi et al. 2010]; 400-950 MPa, 800-950°C [Ridolfi & Renzulli 2012]). Results suggest the recent re-calibration is particularly unreliable for these rocks, and the earlier calibration is 7. Hot Deformation Behavior of SA508Gr.4N Steel for Reactor Pressure Vessels Directory of Open Access Journals (Sweden) YANG Zhi-qiang 2017-08-01 Full Text Available The high-temperature plastic deformation and dynamic recrystallization behavior of SA508Gr.4N steel were investigated through hot deformation tests in a Gleeble1500D thermal mechanical simulator. The compression tests were performed in the temperature range of 1050-1250℃ and the strain rate range of 0.001-0.1s-1 with true strain of 0.16. The results show that from the high-temperature true stress-strain curves of the SA508Gr.4N steel, the main feature is dynamic recrystallization,and the peak stress increases with the decrease of deformation temperature or the increase of strain rate, indicating the experimental steel is temperature and strain rate sensitive material. The constitutive equation for SA508Gr.4N steel is established on the basis of the true stress-strain curves, and exhibits the characteristics of the high-temperature flow behavior quite well, while the activation energy of the steel is determined to be 383.862kJ/mol. Furthermore, an inflection point is found in the θ-σ curve, while the -dθ/dσ-σ curve shows a minimum value. The critical strain increases with increasing strain rate and decreasing deformation temperature. A linear relationship between critical strain (εc and peak strain (εp is found and could be expressed as εc/εp=0.517. The predicted model of critical strain could be described as εc=8.57×10-4Z0.148. 8. The pressure of hot QCD up to $g^{6}$ ln(1/g) CERN Document Server Kajantie, Keijou; Rummukainen, K; Schröder, Y 2003-01-01 The free energy density, or pressure, of QCD has at high temperatures an expansion in the coupling constant g, known so far up to order g^5. We compute here the last contribution which can be determined perturbatively, g^6 ln(1/g), by summing together results for the 4-loop vacuum energy densities of two different three-dimensional effective field theories. We also demonstrate that the inclusion of the new perturbative g^6 ln(1/g) terms, together with the so far unknown perturbative and non-perturbative g^6 terms, could potentially extend the applicability of the resummed coupling constant series down to surprisingly low temperatures. 9. The $N_f^3 g^6$ term in the pressure of hot QCD CERN Document Server Gynther, A; Vuorinen, A 2009-01-01 We determine the first independent part of the g^6 coefficient in the weak coupling expansion of the QCD pressure at high temperatures, the one proportional to the maximal power of the number of quark flavors N_f. In addition to introducing and developing computational methods that can be used in evaluating other parts of the expansion, our calculation provides a result that becomes dominant in the limit of large N_f and a fixed effective coupling g_{eff}^2 = g^2 N_f/2. 10. Chemical vapour deposition of silicon under reduced pressure in a hot-wall reactor: Equilibrium and kinetics International Nuclear Information System (INIS) Langlais, F.; Hottier, F.; Cadoret, R. 1982-01-01 Silicon chemical vapour deposition (SiH 2 Cl 2 /H 2 system), under reduced pressure conditions, in a hot-wall reactor, is presented. The vapour phase composition is assessed by evaluating two distinct equilibria. The homogeneous equilibrium , which assumes that the vapour phase is not in equilibrium with solid silicon, is thought to give an adequate description of the vapour phase in the case of low pressure, high gas velocities, good temperature homogeneity conditions. A comparison with heterogeneous equilibrium enables us to calculate the supersaturation so evidencing a highly irreversible growth system. The experimental determination of the growth rates reveals two distinct temperature ranges: below 1000 0 C, polycrystalline films are usually obtained with a thermally activated growth rate (+40 kcal mole -1 ) and a reaction order, with respect to the predominant species SiCl 2 , close to one; above 1000 0 C, the films are always monocrystalline and their growth rate exhibits a much lower or even negative activation energy, the reaction order in SiCl 2 remaining about one. (orig.) 11. Bench-Scale Development of a Hot Carbonate Absorption Process with Crystallization-Enabled High Pressure Stripping for Post-Combustion CO{sub 2} Capture Energy Technology Data Exchange (ETDEWEB) Lu, Yongqi 2014-02-01 This report summarizes the methodology and preliminary results of a techno-economic analysis on a hot carbonate absorption process (Hot-CAP) with crystallization-enabled high pressure stripping for post-combustion CO{sub 2} capture (PCC). This analysis was based on the Hot-CAP that is fully integrated with a sub-critical steam cycle, pulverized coal-fired power plant adopted in Case 10 of the DOE/NETL’s Cost and Performance Baseline for Fossil Energy Plants. The techno-economic analysis addressed several important aspects of the Hot-CAP for PCC application, including process design and simulation, equipment sizing, technical risk and mitigation strategy, performance evaluation, and cost analysis. Results show that the net power produced in the subcritical power plant equipped with Hot-CAP is 611 MWe, greater than that with Econoamine (550 MWe). The total capital cost for the Hot-CAP, including CO{sub 2} compression, is $399 million, less than that for the Econoamine PCC ($493 million). O&M costs for the power plant with Hot-CAP is $175 million annually, less than that with Econoamine ($178 million). The 20-year levelized cost of electricity (LCOE) for the power plant with Hot-CAP, including CO2 transportation and storage, is 119.4 mills/kWh, a 59% increase over that for the plant without CO2 capture. The LCOE increase caused by CO{sub 2} capture for the Hot-CAP is 31% lower than that for its Econoamine counterpart. 12. Application of isostatic gravity anomaly in the Yellow Sea area Science.gov (United States) Hao, Z.; Qin, J.; Huang, W.; Wu, X. 2017-12-01 In order to study the deep crustal structure of the Yellow Sea area, we used the Airy-Heiskanen model to calculate the isostatic gravity anomaly of this area. Based on the Bouguer gravity anomaly and water depth data of this area, we chose the calculating parameters as standard crustal thickness 30 km, crust-mantle density difference 0.6g/cm3and grid spacing 0.1°×0.1°. This study reveals that there are six faults and four isostatic negative anomalies in the study area. The isostatic anomalies in much of Yellow Sea areas give priority to those with positive anomalies. The isostatic anomalies in North Yellow Sea are higher than South Yellow Sea with Jiashan-Xiangshui fault as the boundary. In the north of the study area, isostatic anomalies are characterized by large areas of positive anomaly. The change is relatively slow, and the trends give priority to the trend NE or NEE. In the middle of the north Yellow Sea basin, there is a local negative anomaly, arranged as a string of beads in NE to discontinuous distribution. Negative anomaly range is small, basically corresponds to the region's former Cenozoic sedimentary basin position. To the south of Jiashan-Xiangshui fault and west of Yellow Sea eastern margin fault, including most of the south Yellow Sea and Jiangsu province, the isostatic anomalies are lower. And the positive and negative anomalies are alternative distribution, and negative anomaly trap in extensive development. The trends give priority to NE, NEE, both to the NW. On the basis of the characteristics of isostatic gravity anomalies, it is concluded that the Yellow Sea belongs to continental crustal isostatic area whose isostatic anomalies is smooth and slow. ReferencesHeiskanen, W. A., F. A. V. Meinesz, and S. A. Korff (1958), The Earth and Its Gravity Field, McGraw-Hill, New York. Meng, X. J., X. H. Zhang, and J. Y. Yang (2014), Geophysical survey in eastern China seas and the characteristics of gravity and magnetic fields, Marine Geoglogy 13. Modelling Hot Air Balloons. Science.gov (United States) Brimicombe, M. W. 1991-01-01 A macroscopic way of modeling hot air balloons using a Newtonian approach is presented. Misleading examples using a car tire and the concept of hot air rising are discussed. Pressure gradient changes in the atmosphere are used to explain how hot air balloons work. (KR) 14. Space Shuttle Main Engine Low Pressure Oxidizer Turbo-Pump Inducer Dynamic Environment Characterization through Water Model and Hot-Fire Testing Science.gov (United States) Arellano, Patrick; Patton, Marc; Schwartz, Alan; Stanton, David 2006-01-01 The Low Pressure Oxidizer Turbopump (LPOTP) inducer on the Block II configuration Space Shuttle Main Engine (SSME) experienced blade leading edge ripples during hot firing. This undesirable condition led to a minor redesign of the inducer blades. This resulted in the need to evaluate the performance and the dynamic environment of the redesign, relative to the current configuration, as part of the design acceptance process. Sub-scale water model tests of the two inducer configurations were performed, with emphasis on the dynamic environment due to cavitation induced vibrations. Water model tests were performed over a wide range of inlet flow coefficient and pressure conditions, representative of the scaled operating envelope of the Block II SSME, both in flight and in ground hot-fire tests, including all power levels. The water test hardware, facility set-up, type and placement of instrumentation, the scope of the test program, specific test objectives, data evaluation process and water test results that characterize and compare the two SSME LPOTP inducers are discussed. In addition, dynamic characteristics of the two water models were compared to hot fire data from specially instrumented ground tests. In general, good agreement between the water model and hot fire data was found, which confirms the value of water model testing for dynamic characterization of rocket engine turbomachinery. 15. Jamming of soft particles: geometry, mechanics, scaling and isostaticity International Nuclear Information System (INIS) Van Hecke, M 2010-01-01 Amorphous materials as diverse as foams, emulsions, colloidal suspensions and granular media can jam into a rigid, disordered state where they withstand finite shear stresses before yielding. Here we review the current understanding of the transition to jamming and the nature of the jammed state for disordered packings of particles that act through repulsive contact interactions and are at zero temperature and zero shear stress. We first discuss the breakdown of affine assumptions that underlies the rich mechanics near jamming. We then extensively discuss jamming of frictionless soft spheres. At the jamming point, these systems are marginally stable (isostatic) in the sense of constraint counting, and many geometric and mechanical properties scale with distance to this jamming point. Finally, we discuss current explorations of jamming of frictional and non-spherical (ellipsoidal) particles. Both friction and asphericity tune the contact number at jamming away from the isostatic limit, but in opposite directions. This allows one to disentangle the distance to jamming and the distance to isostaticity. The picture that emerges is that most quantities are governed by the contact number and scale with the distance to isostaticity, while the contact number itself scales with the distance to jamming. (topical review) 16. The Darfur Swell, Africa: Gravity constraints on its isostatic compensation Science.gov (United States) Crough, S. Thomas The free-air gravity anomaly observed over the Darfur Swell is explainable by local isostatic balance with a root approximately 50 km deep on average. This root depth is similar to that inferred beneath other African domes and beneath oceanic midplate swells, suggesting that the Darfur Swell is a hotspot uplift created by lithospheric reheating. 17. Finite element concept to derive isostatic residual maps Indian Academy of Sciences (India) A new space-domain operator based on the shape function concept of finite element analysis has been developed to derive the residual maps of the Gorda Plate of western United States. The technique does not require explicit assumptions on isostatic models. Besides delineating the Gorda Plate boundary, the residual ... 18. Finite element concept to derive isostatic residual maps ... Indian Academy of Sciences (India) These produce large regional lows that override or tend to mask the smaller anomalies originating from the mid and upper crustal geologic structures. The interpretation and understanding of these structures depend on how effectively the regional gravity anoma- lies are isolated so as to construct the isostatic residual maps. 19. Jamming of soft particles: geometry, mechanics, scaling and isostaticity Energy Technology Data Exchange (ETDEWEB) Van Hecke, M, E-mail: [email protected] [Kamerlingh Onnes Laboratory, Leiden University, PO Box 9504, 2300 RA Leiden (Netherlands) 2010-01-27 Amorphous materials as diverse as foams, emulsions, colloidal suspensions and granular media can jam into a rigid, disordered state where they withstand finite shear stresses before yielding. Here we review the current understanding of the transition to jamming and the nature of the jammed state for disordered packings of particles that act through repulsive contact interactions and are at zero temperature and zero shear stress. We first discuss the breakdown of affine assumptions that underlies the rich mechanics near jamming. We then extensively discuss jamming of frictionless soft spheres. At the jamming point, these systems are marginally stable (isostatic) in the sense of constraint counting, and many geometric and mechanical properties scale with distance to this jamming point. Finally, we discuss current explorations of jamming of frictional and non-spherical (ellipsoidal) particles. Both friction and asphericity tune the contact number at jamming away from the isostatic limit, but in opposite directions. This allows one to disentangle the distance to jamming and the distance to isostaticity. The picture that emerges is that most quantities are governed by the contact number and scale with the distance to isostaticity, while the contact number itself scales with the distance to jamming. (topical review) 20. Demonstration of Fuel Hot-Spot Pressure in Excess of 50 Gbar for Direct-Drive, Layered Deuterium-Tritium Implosions on OMEGA. Science.gov (United States) Regan, S P; Goncharov, V N; Igumenshchev, I V; Sangster, T C; Betti, R; Bose, A; Boehly, T R; Bonino, M J; Campbell, E M; Cao, D; Collins, T J B; Craxton, R S; Davis, A K; Delettrez, J A; Edgell, D H; Epstein, R; Forrest, C J; Frenje, J A; Froula, D H; Gatu Johnson, M; Glebov, V Yu; Harding, D R; Hohenberger, M; Hu, S X; Jacobs-Perkins, D; Janezic, R; Karasik, M; Keck, R L; Kelly, J H; Kessler, T J; Knauer, J P; Kosc, T Z; Loucks, S J; Marozas, J A; Marshall, F J; McCrory, R L; McKenty, P W; Meyerhofer, D D; Michel, D T; Myatt, J F; Obenschain, S P; Petrasso, R D; Radha, P B; Rice, B; Rosenberg, M J; Schmitt, A J; Schmitt, M J; Seka, W; Shmayda, W T; Shoup, M J; Shvydky, A; Skupsky, S; Solodov, A A; Stoeckl, C; Theobald, W; Ulreich, J; Wittman, M D; Woo, K M; Yaakobi, B; Zuegel, J D 2016-07-08 A record fuel hot-spot pressure P_{hs}=56±7 Gbar was inferred from x-ray and nuclear diagnostics for direct-drive inertial confinement fusion cryogenic, layered deuterium-tritium implosions on the 60-beam, 30-kJ, 351-nm OMEGA Laser System. When hydrodynamically scaled to the energy of the National Ignition Facility, these implosions achieved a Lawson parameter ∼60% of the value required for ignition [A. Bose et al., Phys. Rev. E 93, 011201(R) (2016)], similar to indirect-drive implosions [R. Betti et al., Phys. Rev. Lett. 114, 255003 (2015)], and nearly half of the direct-drive ignition-threshold pressure. Relative to symmetric, one-dimensional simulations, the inferred hot-spot pressure is approximately 40% lower. Three-dimensional simulations suggest that low-mode distortion of the hot spot seeded by laser-drive nonuniformity and target-positioning error reduces target performance. 1. Effects of a hot-water extract of porcini (Boletus aestivalis) mushrooms on the blood pressure and heart rate of spontaneously hypertensive rats. Science.gov (United States) Midoh, Naoki; Miyazawa, Noriko; Eguchi, Fumio 2013-01-01 The repeated once-daily oral administration of a hot-water extract of porcini, Boletus aestivalis, mushrooms (WEP) to spontaneously hypertensive rats (SHR) for 18 weeks decreased the systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate. The WEP administration also decreased blood urea nitrogen (BUN), creatinine (Cre), and triglyceride (TG), and increased high-density lipoprotein-cholesterol (HDL-C) in the blood, suggesting that WEP improved the status of hypertension, as well as the high heart rate and metabolic abnormalities involved in hypertension. 2. Two-phase flow experiments on Counter-Current Flow Limitation in a model of the hot leg of a pressurized water reactor (2015 test series) International Nuclear Information System (INIS) Beyer, Matthias; Lucas, Dirk; Pietruske, Heiko; Szalinski, Lutz 2016-12-01 Counter-Current Flow Limitation (CCFL) is of importance for PWR safety analyses in several accident scenarios connected with loss of coolant. Basing on the experiences obtained during a first series of hot leg tests now new experiments on counter-current flow limitation were conducted in the TOPFLOW pressure vessel. The test series comprises air-water tests at 1 and 2 bar as well as steam-water tests at 10, 25 and 50 bar. During the experiments the flow structure was observed along the hot leg model using a high-speed camera and web-cams. In addition pressure was measured at several positions along the horizontal part and the water levels in the reactor-simulator and steam-generator-simulator tanks were determined. This report documents the experimental setup including the description of operational and special measuring techniques, the experimental procedure and the data obtained. From these data flooding curves were obtained basing on the Wallis parameter. The results show a slight shift of the curves in dependency of the pressure. In addition a slight decrease of the slope was found with increasing pressure. Additional investigations concern the effects of hysteresis and the frequencies of liquid slugs. The latter ones show a dependency on pressure and the mass flow rate of the injected water. The data are available for CFD-model development and validation. 3. Two-phase flow experiments on Counter-Current Flow Limitation in a model of the hot leg of a pressurized water reactor (2015 test series) Energy Technology Data Exchange (ETDEWEB) Beyer, Matthias; Lucas, Dirk; Pietruske, Heiko; Szalinski, Lutz 2016-12-15 Counter-Current Flow Limitation (CCFL) is of importance for PWR safety analyses in several accident scenarios connected with loss of coolant. Basing on the experiences obtained during a first series of hot leg tests now new experiments on counter-current flow limitation were conducted in the TOPFLOW pressure vessel. The test series comprises air-water tests at 1 and 2 bar as well as steam-water tests at 10, 25 and 50 bar. During the experiments the flow structure was observed along the hot leg model using a high-speed camera and web-cams. In addition pressure was measured at several positions along the horizontal part and the water levels in the reactor-simulator and steam-generator-simulator tanks were determined. This report documents the experimental setup including the description of operational and special measuring techniques, the experimental procedure and the data obtained. From these data flooding curves were obtained basing on the Wallis parameter. The results show a slight shift of the curves in dependency of the pressure. In addition a slight decrease of the slope was found with increasing pressure. Additional investigations concern the effects of hysteresis and the frequencies of liquid slugs. The latter ones show a dependency on pressure and the mass flow rate of the injected water. The data are available for CFD-model development and validation. 4. Bench-Scale Development of a Hot Carbonate Absorption Process with Crystallization-Enabled High-Pressure Stripping for Post-Combustion CO{sub 2} Capture Energy Technology Data Exchange (ETDEWEB) Lu, Yongqi; DeVries, Nicholas; Ruhter, David; Manoranjan, Sahu; Ye, Qing; Ye, Xinhuai; Zhang, Shihan; Chen, Scott; Li, Zhiwei; O' Brien, Kevin 2014-03-31 A novel Hot Carbonate Absorption Process with Crystallization-Enabled High-Pressure Stripping (Hot-CAP) has been developed by the University of Illinois at Urbana-Champaign and Carbon Capture Scientific, LLC in this three-year, bench-scale project. The Hot-CAP features a concentrated carbonate solution (e.g., K{sub 2}CO{sub 3}) for CO{sub 2} absorption and a bicarbonate slurry (e.g., KHCO{sub 3}) for high-pressure CO{sub 2} stripping to overcome the energy use and other disadvantages associated with the benchmark monoethanolamine (MEA) process. The project was aimed at performing laboratory- and bench-scale experiments to prove its technical feasibility and generate process engineering and scale-up data, and conducting a techno-economic analysis (TEA) to demonstrate its energy use and cost competitiveness over MEA. To meet project goals and objectives, a combination of experimental, modeling, process simulation, and economic analysis studies were applied. Carefully designed and intensive experiments were conducted to measure thermodynamic and reaction engineering data relevant to four major unit operations in the Hot-CAP (i.e., CO{sub 2} absorption, CO{sub 2} stripping, bicarbonate crystallization, and sulfate reclamation). The rate promoters that could accelerate the CO{sub 2} absorption rate into the potassium carbonate/bicarbonate (PCB) solution to a level greater than that into the 5 M MEA solution were identified, and the superior performance of CO{sub 2} absorption into PCB was demonstrated in a bench-scale packed-bed column. Kinetic data on bicarbonate crystallization were developed and applied for crystallizer design and sizing. Parametric testing of high-pressure CO{sub 2} stripping with concentrated bicarbonate-dominant slurries at high temperatures ({>=}140{degrees}C) in a bench-scale stripping column demonstrated lower heat use than with MEA. The feasibility of a modified process for combining SO{sub 2} removal with CO{sub 2} capture was preliminarily 5. TiO{sub 2} Processed by pressurized hot solvents as a novel photocatalyst for photocatalytic reduction of carbon dioxide Energy Technology Data Exchange (ETDEWEB) Reli, Martin, E-mail: [email protected] [Institute of Environmental Technology, VŠB-TU Ostrava, 17. listopadu 15/2172, 708 33 Ostrava (Czech Republic); Kobielusz, Marcin [Faculty of Chemistry, Jagiellonian University in Kraków, ul. Ingardena 3, 30-060 Kraków (Poland); Matějová, Lenka [Institute of Environmental Technology, VŠB-TU Ostrava, 17. listopadu 15/2172, 708 33 Ostrava (Czech Republic); Daniš, Stanislav [Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 5, 121 16 Prague 2 (Czech Republic); Macyk, Wojciech [Centre ENET, VŠB-TU Ostrava, 17. listopadu 15/2172, 708 33 Ostrava (Czech Republic); Obalová, Lucie [Institute of Environmental Technology, VŠB-TU Ostrava, 17. listopadu 15/2172, 708 33 Ostrava (Czech Republic); Kuśtrowski, Piotr; Rokicińska, Anna [Faculty of Chemistry, Jagiellonian University in Kraków, ul. Ingardena 3, 30-060 Kraków (Poland); Kočí, Kamila [Institute of Environmental Technology, VŠB-TU Ostrava, 17. listopadu 15/2172, 708 33 Ostrava (Czech Republic); Centre ENET, VŠB-TU Ostrava, 17. listopadu 15/2172, 708 33 Ostrava (Czech Republic) 2017-01-01 Highlights: • Synthesis of anatase-brookite TiO{sub 2} photocatalysts has been described. • The materials photocatalyze carbon dioxide reduction to methane. • The photoactivity of the synthesized composites has been compared with the activity of anatase-rutile material (P25). • The influence of electronic structure on photocatalytic activity has been discussed. - Abstract: Anatase-brookite TiO{sub 2} photocatalysts were prepared by the sol-gel process controlled within reverse micelles and processing by pressurized hot solvents–water/methanol/water (TiO{sub 2}(M)) and water/ethanol/water (TiO{sub 2}(E)), as an unconventional alternative to common calcination. The main goal of this work was to prepare anatase-brookite mixtures by processing by two different alcohols (methanol and ethanol) and evaluate the influence of the alcohol on the photocatalytic activity. Prepared photocatalysts were characterized by organic elemental analysis, nitrogen physisorption, XRD, UV–vis, photoelectrochemical and spectroelectrochemical measurements and XPS. The prepared photocatalysts efficiency was tested on the photocatalytic reduction of carbon dioxide and compared with commercial TiO{sub 2} Evonik P25. Both prepared nanocomposites were more efficient towards methane production but Evonik P25 was the most efficient towards hydrogen generated through water splitting. The higher performance of anatase-brookite mixture towards methane production can be explained by (i) a higher photocatalytic activity of brookite than rutile; (ii) a large surface area of anatase-brookite composites enabling better carbon dioxide adsorption; (iii) the photoinduced electron transfer from the brookite conduction band to the anatase conduction band. On the other hand, a higher production of hydrogen in the presence of Evonik P25 is caused by a better charge separation in anatase-rutile than anatase-brookite phase compositions. TiO{sub 2}(M) appeared more active than TiO{sub 2}(E) in the 6. Heat transfer and pressure drop of a gasket-sealed plate heat exchanger depending on operating conditions across hot and cold sides Energy Technology Data Exchange (ETDEWEB) Ahn, Joon [Kookmin University, Seoul (Korea, Republic of); Kim, Hyouck Ju [Korea Institute of Energy Research, Daejeon (Korea, Republic of) 2016-05-15 In a gas engine based cogeneration system, heat may be recovered from two parts: Jacket water and exhaust gas. The heat from the jacket water is often recovered using a plate-type heat exchanger, and is used for room heating and/or hot water supply applications. Depending on the operating conditions of an engine and heat recovery system, there may be an imbalance in the flow rate and supply pressure between the engine side and the heat-recovery side of the heat exchanger. This imbalance causes deformation of the plate, which affects heat transfer and pressure drop characteristics. In the present study, the heat transfer and pressure drop inside a heat exchanger were investigated under varying hot-side and cold-side operating conditions. Thermal efficiency of the plate heat exchanger decreases up to 30% with an operating engine load of 50%. A correction factor for the pressure drop correlation is proposed to account for the deformation caused by an imbalance between the two sides of a heat exchanger. 7. Microstructure and textural characterization of hot extruded Zr-2.5Nb alloy PHWR pressure tube fabricated by various ingot processing route International Nuclear Information System (INIS) Vaibhaw, Kumar; Jha, S.K.; Saibaba, N.; Neogy, S.; Mani Krishna, K.V.; Srivastava, D.; Dey, G.K. 2011-01-01 Zr-2.5 Nb alloys finds its applications as a pressure tube component in pressure tube type thermal reactors such as PHWRs and RBMK due to properties attributed such as low neutron absorption cross section, high temperature strength and corrosion resistance etc. Manufacturing of this life time components involves series of thermo-mechanical processes of hot working and cold working with intermediate annealing. The life time of Pressure tube are limited due to their diametral creep properties which is governed by metallurgical characteristics such as texture, microstructure dislocation density etc. The primary breakdown of cast structure in Vacuum Arc Melted ingot can be effected by either hot extrusion or forging in single or multiple stages before final hot extrusion step into the blank for manufacturing of seamless pressure tube. Elevated temperature deformation carried out in hot working above the recrystallization temperature would enable impositions of large strains in single step. This deformation causes a significant change in the microstructure of the material and depends on process parameters such as extrusion ratio, temperature and strain rate. Basic microstructure developed at this deformation stage has significant bearing on the final properties of the material fabricated with subsequent cold working steps. The major texture in α+β Zr-2.5 Nb alloy is established during final extrusion to blank which does not change significantly during subsequent cold pilgering. However, microstructure is modified significantly in subsequent cold working which can be effected by cold pilgering or cold drawing in single or multiple steps. Present paper brings out the various ingot processing routes using forging and or extrusion followed for fabrication of pressure tubes. The development of texture and microstructures has been discussed at the blank stage from these processing routes and also with respect to varying extrusion variable such as extrusion ratio 8. Densification of porous bodies in a granular pressure-transmitting medium International Nuclear Information System (INIS) Olevsky, E.A.; Ma, J.; LaSalvia, J.C.; Meyers, M.A. 2007-01-01 Densification is a critical step in the manufacture of near-net-shaped components via powder processing. A non-isostatic stress state will in general result in shape distortion in addition to densification. In the quasi-isostatic pressing (QIP) process the green body is placed into a granular pressure-transmitting medium (i.e. PTM), which is itself contained in a rigid die. Upon the application of a uniaxial load, the PTM redistributes the tractions on the green body, thereby creating a stress state that is quasi-isostatic. The character of the deformation of the PTM is studied using model experiments on pressing of the PTM in a rigid die and a scanning electron microscopy analysis of the PTM powder. An important problem of the optimization of the PTM chemical composition enabling the maximum densification of a porous specimen with the minimum possible shape distortion is solved. The results of modeling agree satisfactorily with the experimental data on cold QIPing Ti and Ni powder samples and hot QIPing TiC-TiNi cermet composites 9. Powder metallurgy Al–6Cr–2Fe–1Ti alloy prepared by melt atomisation and hot ultra-high pressure compaction International Nuclear Information System (INIS) Dám, Karel; Vojtěch, Dalibor; Průša, Filip 2013-01-01 Al--6Cr--2Fe--1Ti alloy was prepared by melt atomisation into rapidly solidified powder. The powder was compacted using uniaxial hot compression at an ultra-high pressure (6 GPa). The samples were pressed at 300, 400 and 500 °C. The structure, mechanical properties and thermal stability were examined and compared with those of the commercially available Al--12Si--1Cu--1Mg--1Ni casting alloy, which is considered thermally stable. It was shown that the hot compression at ultra-high pressure results in a compact and pore-free material with excellent mechanical properties. The elevated pressing temperatures were found to be effective at increasing the mechanical stability after applying the ultra-high pressure. The results of thermal stability testing revealed that the mechanical properties do not change significantly at high temperature, even after 100 h of annealing at 400 °C. In addition, the Al--6Cr--2Fe--1Ti alloy exhibited very good creep resistance. A comparison between the commercial Al--12Si--1Cu--1Mg--1Ni alloy and the powder metallurgy alloy shows that this alloy has significantly better mechanical properties and thermal stability. 10. Powder metallurgy Al-6Cr-2Fe-1Ti alloy prepared by melt atomisation and hot ultra-high pressure compaction Energy Technology Data Exchange (ETDEWEB) Dam, Karel, E-mail: [email protected] [Department of Metals and Corrosion Engineering, Institute of Chemical Technology, Prague, Technicka 5, 166 28 Prague 6 (Czech Republic); Vojtech, Dalibor; Prusa, Filip [Department of Metals and Corrosion Engineering, Institute of Chemical Technology, Prague, Technicka 5, 166 28 Prague 6 (Czech Republic) 2013-01-10 Al--6Cr--2Fe--1Ti alloy was prepared by melt atomisation into rapidly solidified powder. The powder was compacted using uniaxial hot compression at an ultra-high pressure (6 GPa). The samples were pressed at 300, 400 and 500 Degree-Sign C. The structure, mechanical properties and thermal stability were examined and compared with those of the commercially available Al--12Si--1Cu--1Mg--1Ni casting alloy, which is considered thermally stable. It was shown that the hot compression at ultra-high pressure results in a compact and pore-free material with excellent mechanical properties. The elevated pressing temperatures were found to be effective at increasing the mechanical stability after applying the ultra-high pressure. The results of thermal stability testing revealed that the mechanical properties do not change significantly at high temperature, even after 100 h of annealing at 400 Degree-Sign C. In addition, the Al--6Cr--2Fe--1Ti alloy exhibited very good creep resistance. A comparison between the commercial Al--12Si--1Cu--1Mg--1Ni alloy and the powder metallurgy alloy shows that this alloy has significantly better mechanical properties and thermal stability. 11. The hot gas cleaning with multifunctional sorbent technique at 1-20 bar pressure; Kaasujen kuumapuhdistus multifunktionaalisella sorbenttitekniikalla 1-20 bar:n paineessa Energy Technology Data Exchange (ETDEWEB) Jaanu, K.; Orjala, M.; Paakkinen, K.; Rantanen, J. [VTT Energy, Espoo (Finland) 1996-12-01 The aim of the research was to study the simultaneous hot gas cleanup of alkali metals and selected heavy metals under pressure of 1-20 bar using multifunctional sorbent technology, to investigate effects of it on sulfur and nitrogen emissions and to improve the total efficiency of the hot gas cleanup method by reducing the concentrations of harmful components to the level required by the gas turbines. The research has started in the year 1993. The optimization of the test facility at 900 deg C and 20 bar has been accomplished, as targeted. The main topics have been the alkali metals. The main targets of the year 1994 was to concentrate on the research of sorbent effectiveness to remove the impurities like alkalies etc. from the flue gas. Furthermore researches on kinetics and mechanisms were started. The results showed that the developed multifunctional sorbent are highly effective to remove alkalies from the flue gas. Also a mechanism for alkali and lead sorption was proposed. The main topics for 1995 were scheduled to be the completion of the kinetic and mechanical studies and the modelling and the estimation of the data for the pilot scale unit. The kinetic data for one sorbent has been completed and a model for that has also been developed. The measured and calculated results are indicating that the developed multifunctional sorption process is highly effective to remove alkalies and heavy metals such as lead and cadmium from high-temperature combustion gases. The tests are carried out mainly using the pressurized entrained flow reactor of VTT Energy, located in Jyvaeskylae, and in the university of Arizona, where the tests are conducted under atmospheric pressure. Some comparisons of the results might be made with those of Aabo Akademi during the future modelling. 3. The results are applied to purification of the hot gases in boilers, power and process industry. (Abstract Truncated) 12. Rapid production of metallurgical coke by a pressurized hot-briquetting method. Netsukan kaatsu seikei ni yoru cokes no jinsoku seizo no kokoromi Energy Technology Data Exchange (ETDEWEB) Miura, K.; Hayashi, J.; Noguchi, N. (Kyoto University, Kyoto (Japan). Research Laboratory of Carbonaceous Resources Conversion Technology); Hashimoto, K. (Kyoto University, Kyoto (Japan). Faculty of Engineering) 1993-09-20 Rapid production of metallurgical coke from non- and slightly coking coals was studied by pressurized hot-briquetting method. Coal specimens were filled into the mold after pulverizing, and heated at a constant temperature rise rate up to caking temperature under loading pressure to obtain caked coal specimens. Such specimens were then carbonized in nitrogen gas at 800[degree]C. As a result, the coke obtained was superior in compressive strength as compared with commercial cokes, however, its CO2 reactivity was very high requiring heating up to 1,000[degree]C to decrease it, while the reactivity was strongly dependent on coal kind. The optimum processing conditions for slightly coking coal were as follows; loading pressure: 10 [times] 10[sup 5] Pa or more, temperature range under loading pressure: 300-450[degree]C, temperature rise rate: 2-100[degree]C/min, and caking temperature: nearly 500[degree]C. No coke could be produced from coking coals because no volatile matter could be removed from it in a short time under pressure. 13 refs., 8 figs., 1 tab. 13. Effects of internal gas pressure and microstructure on the mechanisms of hot-pressing and swelling in ceramics. Final report, June 1, 1979-May 31, 1980 International Nuclear Information System (INIS) Solomon, A.A. 1980-08-01 The results of the study of the effects of internal and external gas pressures on ceramics are summarized. The new experimental systems for studying these phenomena are described. The study has shown that the rate of volume change in ZnO is linearly related to the total pressure driving force. Swelling and hot-pressing can be described on a consistent basis in terms of this driving force. For ZnO, Ni and UO 2 the rate of volume change is dependent on bulk diffusion. The porosity evolution during swelling is described and the resintering phenomenon is identified. Various models for pore growth and shrinkage are considered and related to the behavior of the different systems 14. Hot Flashes Science.gov (United States) Hot flashes Overview Hot flashes are sudden feelings of warmth, which are usually most intense over the face, neck and chest. Your skin might redden, as if you're blushing. Hot flashes can also cause sweating, and if you ... 15. HOT 2015 DEFF Research Database (Denmark) Hannibal, Sara Stefansen 2016-01-01 HOT samler og formidler 21 literacykyndiges bud på, hvad der er hot, og hvad der bør være hot inden for literacy – og deres begrundelser for disse bud.......HOT samler og formidler 21 literacykyndiges bud på, hvad der er hot, og hvad der bør være hot inden for literacy – og deres begrundelser for disse bud.... 16. Incineration ashes conditioning by isostatic pressing and melting International Nuclear Information System (INIS) Jouan, A.; Ouvrier, N.; Teulon, F. 1990-01-01 Alpha-bearing solid incineration wastes are conditioned for two principal reasons: to enhance the quality of the finished product for long-term storage, and to reduce the total waste volume. Isostatic pressing parameters were defined using containers 36 mm in diameter; the physicochemical properties of the compacted ashes were determined with 140 mm diameter containers and industrial feasibility was demonstrated with a large (300 mm diameter) container. Two types of ashes were used: ashes fabricated at Marcoule (either in devices developed by the CEA for the MELOX project with a standard MELOX composition, or by direct incineration at COGEMA's UP1 plant) and fly ash from a domestic waste incinerator. A major engineering study was also undertaken to compare the three known ash containment processes: isostatic pressing, melting, and cement-resin matrix embedding. The flowsheet, operational chronology and control principles were detailed for each process, and a typical plant layout was defined to allow comparisons of both investment and operating costs 17. Hot working alkali halides for laser window applications International Nuclear Information System (INIS) Koepke, B.G.; Anderson, R.H.; Stokes, R.J. 1975-01-01 The techniques used to hot work alkali halide crystals into laser window blanks are reviewed. From the point of view of high power laser window applications one of the materials with a high figure of merit is KCl. Thus the materials examined are KCl and alloys of KCl-KBr containing 5 mole percent KBr. The fabrication techniques include conventional and constrained press forging, isostatic press forging and hot rolling. Optical properties are paramount to the ultimate usefulness of these materials. Results on the optical properties of the hot worked material are included together with mechanical properties and microstructural data 18. Application of hot isostatic pressing to the manufacture of complex shaped moulds and tools International Nuclear Information System (INIS) Rigal, E.; Baccino, R.; Federzoni, L.; Moret, F. 2000-01-01 In this article, we briefly recall the physical mechanisms at the origin of the Barkhausen effect in ferromagnetic mediums and the thermoelectric power in conductor metals. We then present, for each of these phenomena, the measurement principles and their sensitivity to the microstructural state, notably in the case of precipitation phenomena and in the ones linked to plastic deformation. Finally, in the case of the formation of precipitates in an iron-based alloy, we show the complementarity of both techniques. (authors) 19. Pengaruh Temperatur Pada Proses Hot Isostatic Pressing Terhadap Porositas, Keausan Dan Mikrostruktur Sludge Powder Duralumin OpenAIRE Multazam, Ahmad; Suprapto, Wahyono; Pratikto, Pratikto 2014-01-01 Sludge is the starting raw material in the process of forming wheels with forging method. Performance wheels strongly influenced by the quality of sludge. Sludge should have physical properties that light , soft and easy strengthened. One material that can be used as materials for sludge are: duralumin material. Duralumin is another name for aluminum & copper alloy (Al / Cu) with a Cu content of about 4 %. Making sludge powder duralumin with powder metallurgical methods can improve the qu... 20. The feasibility of bonding aluminum alloy 6061 via hot isostatic pressing (HIP)/rolling International Nuclear Information System (INIS) Fenolietto, R.A. 1991-01-01 The advantage of developing a HIP bonding process for dispersion fuel plates is that applying a thin cladding in a more uniform manner could allow the upper limit for LEU U 3 Si-Al dispersion fuel plate densities to be overcome. Since much less mechanical deformation would be required, the existing process limitations on the density could be removed, theoretically allowing more fuel to be added. These increases are, of course, subject to irradiation behavior of the higher loadings which is not addressed in this paper. Initial results indicate that aluminum Alloy 6061 can be successfully bonded by seal welding via electron beam (EB), HIPping, and finishing with a limited amount of rolling. (orig.) 1. Kinetics and mechanisms of creep in hot isostatically pressed niobium carbide International Nuclear Information System (INIS) Nixon, R.D.; Davis, R.F.; Bentley, J. 1986-01-01 Constant compressive stress creep experiments in the temperature and stress ranges of 1730K - 2100K and 16 MN/m 2 - 70 MM/m 2 on HIPed NbC 0.74 have revealed stress exponents of 2.0 under stress levels of 16-54 MN/m 2 at all temperatures investigated and 3.2 under stress levels of 54-70 MN/m 2 at 1830K. The activation energy of steady state creep is approximately 230 kJ/mol in the temperature range of 1730K - 1930K under 48-54 MN/m 2 and 470 kJ/mol in the temperature range of 1900K - 2100K under 64 MN/m 2 . TEM of the annealed but uncrept material reveals grown-in dislocation subboundaries. At 1730K and under 34-54 MN/m 2 , these subboundaries become single dislocations and dipoles. At 1830K and under 54-70 MN/m 2 the subboundaries evolve into simple tilt boundaries which are occasionally knitted, indicating more glide activity at higher stresses. At 1930K and under 34-54 MN/m 2 , hexagonal subboundaries form, but are not as well defined as in the annealed material. At 2100K and under 16-30 MN/m 2 , the subboundaries are well-defined hexagonal networks which become polygonized under higher stresses on 64 MN/m 2 . The experimental and TEM results indicate that at low temperatures (below 0.5 T m = 2073K) and at all stresses, creep occurs by dislocation glide which is accompanied by subgrain and high angle boundary interaction. At high temperature (above 0.5 T m ), strain occurs by glide and subboundary movement; recovery occurs by climb in the subboundary 2. La2O3-reinforced W and W-V alloys produced by hot isostatic pressing International Nuclear Information System (INIS) Munoz, A.; Monge, M.A.; Savoini, B.; Rabanal, M.E.; Garces, G.; Pareja, R. 2011-01-01 W and W-V alloys reinforced with La 2 O 3 particles have been produced by MA and subsequent HIP at 1573 K and 195 MPa. The microstructure of the consolidated alloys has been characterized by scanning electron microscopy, energy dispersive spectroscopy analyses and X-ray diffraction. The mechanical properties were studied by nanoindentation measurements. The results show that practically full dense billets of W-V, W-V-La 2 O 3 and W-La 2 O 3 alloys can be produced. The microstructure analysis has shown that islands of V are present in W-V and W-V-1La 2 O 3 alloys. In W-1La 2 O 3 islands of La 2 O 3 are also present. The nanohardness of the W matrix increases with the addition of V, while decreases with the addition of La 2 O 3 . 3. Influence of purity level on the mechanical properties of hot isostatically pressed beryllium International Nuclear Information System (INIS) Odegard, B.C. Jr. 1979-09-01 The procurement of a quantity of ultra-pure beryllium powder combined with special handling from powder to billet form resulted in the fabrication of high purity beryllium. The mechanical properties of these billets were contrasted to those of commercial grade billets to determine the influence of impurities and powder processing. The tensile test results show that the strength values are primarily dependent on the grain size in a behavior predictable by the Hall-Petch relationship. Only a fraction of the strength differential can be attributed to metallic impurities in solution. The grain size is controlled by the powder size distribution. The ductility is dominated by both grain size and oxide content. The fine grained, low oxide billets exhibited the highest ductilities. There is evidence to suggest that oxide distribution has a large influence on the ductility. The fracture toughness was highest for the high purity beryllium billets 4. Hydrostatic high pressures for material deformations. Application to Chevrel phase superconductors International Nuclear Information System (INIS) Massat, H. 1984-01-01 The effect of hydrostatic high pressures on the ductility of materials is reviewed and applications are made to powder metallurgy under isostatic pressure and hydrostatic extrusion of superconductors [fr 5. Arsenic species determination in human scalp hair by pressurized hot water extraction and high performance liquid chromatography-inductively coupled plasma-mass spectrometry. Science.gov (United States) Morado Piñeiro, Andrés; Moreda-Piñeiro, Jorge; Alonso-Rodríguez, Elia; López-Mahía, Purificación; Muniategui-Lorenzo, Soledad; Prada-Rodríguez, Darío 2013-02-15 Analytical methods for the determination of total arsenic and arsenic species (mainly As(III) and As(V)) in human scalp hair have been developed. Inductively coupled plasma-mass spectrometry (ICP-MS) and high performance liquid chromatography (HPLC) coupled to ICP-MS have been used for total arsenic and arsenic species determination, respectively. The proposed methods include a "green", fast, high efficient and automated species leaching procedure by pressurized hot water extraction (PHWE). The operating parameters for PHWE including modifier concentration, extraction temperature, static time, extraction steps, pressure, mean particle size, diatomaceous earth (DE) mass/sample mass ratio and flush volume were studied using design of experiments (Plackett-Burman design PBD). Optimum condition implies a modifier concentration (acetic acid) of 150 mM and powdered hair samples fully mixed with diatomaceous earth (DE) as a dispersing agent at a DE mass/sample mass ratio of 5. The extraction has been carried out at 100°C and at an extraction pressure of 1500 psi for 5 min in four extraction step. Under optimised conditions, limits of quantification of 7.0, 6.3 and 50.3 ng g(-1) for total As, As(III) and As(V), respectively were achieved. Repeatability of the overall procedure (4.4, 7.2 and 2.1% for total As, As(III) and As(V), respectively) was achieved. The analysis of GBW-07601 (human hair) certified reference material was used for validation. The optimised method has been finally applied to several human scalp hair samples. Copyright © 2012 Elsevier B.V. All rights reserved. 6. Use of Zircaloy 4 material for the pressure vessels of hot and cold neutron sources and beam tubes for research reactors International Nuclear Information System (INIS) Scheuer, A.; Gutsmiedl, E. 1999-01-01 The material Zircaloy 4 can be used for the pressure retaining walls for the cold and hot neutron sources and beam tubes. For the research reactor FRM-II of the Technical University Munich, Germany, the material Zircaloy 4 were chosen for the vessels of the cold and hot neutron source and for the beam tube No. 6. The sheets and forgings of Zircaloy 4 were examined in the temperature range between -256 deg. C and 250 deg. C. The thickness of the sheets are 3, 4, 5 and 10 mm, the maximum diameter of the forgings was 560 mm. This great forging diameters are not be treated in the ASTM rule B 351 for nuclear material, so a special approval with independent experts was necessary. The requirements for the material examinations were specified in a material specification and material test sheets which based on the ASTM rules B 351 and B 352 with additional restriction and additional requirements of the basic safety concept for nuclear power plants in Germany, which was take into consideration in the nuclear licensing procedure. Charpy-V samples were carried out in the temperature range between -256 deg. C and 150 deg. C to get more information on the ductile behaviour of the Zircaloy 4. The results of the sheet examination confirm the requirements of the specifications, the results of the forging examination in the tangential testing direction are lower than specified and expected for the tensile strength. The axial and transverse values confirm the specification requirements. For the strength calculation of the pressure retaining wall a reduced material value for the forgings has to take into consideration. The material behaviour of Zircaloy 4 under irradiation up to a fluence of ∼ 1x10 22 n/cm 2 was investigated. The loss of ductility was determined. As an additional criteria the variation of the fracture toughness was studies. Fracture mechanic calculations of the material were carried out in the licensing procedure with the focus to fulfill the leak before rupture 7. Use of Zircaloy 4 material for the pressure vessels of hot and cold neutron sources and beam tubes for research reactors International Nuclear Information System (INIS) Gutsmiedl, Erwin 2001-01-01 The material Zircaloy 4 can be used for the pressure retaining walls for the cold and hot neutron sources and beam tubes. For the research reactor FRM-II of the Technical University Munich, Germany, the material Zircaloy 4 were chosen for the vessels of the cold and hot neutron source and for the beam tube No. 6. The sheets and forgings of Zircaloy 4 were examined in the temperature range between -256degC and 250degC. The thickness of the sheets are 3, 4, 5 and 10 mm, the maximum diameter of the forgings was 560 mm. This great forging diameters are not be treated in the ASTM rule B 351 for nuclear material, so a special approval with independent experts was necessary. The requirements for the material examinations were specified in a material specification and material test sheets which based on the ASTM rules B 351 and B 352 with additional restriction and additional requirements of the basic safety concept for nuclear power plants in Germany, which was taken into consideration in the nuclear licensing procedure. Charpy-V samples were carried out in the temperature range between -256degC and 150degC to get more information on the ductile behaviour of the Zircaloy 4. The results of the sheet examination confirm the requirements of the specifications, the results of the forging examination in the tangential testing direction are lower than specified and expected for the tensile strength. The axial and transverse values confirm the specification requirements. For the strength calculation of the pressure retaining wall a reduced material value for the forgings has to taken into consideration. The material behaviour of Zircaloy 4 under irradiation up to a fluence of ∼1·10 22 n/cm 2 was investigated. The loss of ductility was determined. As an additional criteria the variation of the fracture toughness was studies. Fracture mechanic calculations of the material were carried out in the licensing procedure with the focus to fulfill the leak before rupture criteria of 8. Extending the applicability of pressurized hot water extraction to compounds exhibiting limited water solubility by pH control: curcumin from the turmeric rhizome. Science.gov (United States) Euterpio, Maria Anna; Cavaliere, Chiara; Capriotti, Anna Laura; Crescenzi, Carlo 2011-11-01 Pressurized hot water extraction (PHWE, also known as subcritical water extraction) is commonly considered to be an environmentally friendly extraction technique that could potentially replace traditional methods that use organic solvents. Unfortunately, the applicability of this technique is often limited by the very low water solubility of the target compounds, even at high temperatures. In this paper, the scope for broadening the applicability of PHWE by adjusting the pH of the water used in the extraction is demonstrated in the extraction of curcumin (which exhibits very limited water solubility) from untreated turmeric (Curcuma longa L.) rhizomes. Although poor extraction yields were obtained, even at high temperatures when using degassed water or neutral phosphate buffer as the extraction medium, yields exceeding those obtained by Soxhlet extraction were achieved using highly acidic pH buffers due to curcumin protonation. The influence of the temperature, pH, and buffer concentration on the extraction yield were investigated in detail by means of a series of designed experiments. Optimized conditions for the extraction of curcumin from turmeric by PHWE were estimated at 197 °C using 62 g/L buffer concentration at pH 1.6. The relationships between these variables were subjected to statistical analysis using response surface methodology. 9. A Metabolomics-Guided Exploration of the Phytochemical Constituents of Vernonia fastigiata with the Aid of Pressurized Hot Water Extraction and Liquid Chromatography-Mass Spectrometry. Science.gov (United States) Masike, Keabetswe; Khoza, Bradley S; Steenkamp, Paul A; Smit, Elize; Dubery, Ian A; Madala, Ntakadzeni E 2017-07-27 Vernonia fastigiata is a multi-purpose nutraceutical plant with interesting biological properties. However, very little is known about its phytochemical composition and, thus the need for its phytochemical characterization. In the current study, an environmentally friendly method, pressurized hot water extraction (PHWE), was used to extract metabolites from the leaves of V. fastigiata at various temperatures (50 °C, 100 °C, 150 °C and 200 °C). Ultra-high performance liquid chromatography-quadrupole time of flight mass spectrometry (UHPLC-qTOF-MS) analysis in combination with chemometric methods, particularly principal component analysis (PCA) and liquid/gas chromatography mass spectrometry (XCMS) cloud plots, were used to descriptively visualize the data and identify significant metabolites extracted at various temperatures. A total of 25 different metabolites, including hydroxycinnamic acid derivatives, clovamide, deoxy-clovamide and flavonoids, were noted for the first time in this plant. Overall, an increase in extraction temperature resulted in an increase in metabolite extraction during PHWE. This study is the first scientific report on the phytochemical composition of V. fastigiata , providing insight into the components of the chemo-diversity of this important plant. 10. Evaluation of browning ratio in an image analysis of apple slices at different stages of instant controlled pressure drop-assisted hot-air drying (AD-DIC). Science.gov (United States) Gao, Kun; Zhou, Linyan; Bi, Jinfeng; Yi, Jianyong; Wu, Xinye; Zhou, Mo; Wang, Xueyuan; Liu, Xuan 2017-06-01 Computer vision-based image analysis systems are widely used in food processing to evaluate quality changes. They are able to objectively measure the surface colour of various products since, providing some obvious advantages with their objectivity and quantitative capabilities. In this study, a computer vision-based image analysis system was used to investigate the colour changes of apple slices dried by instant controlled pressure drop-assisted hot air drying (AD-DIC). The CIE L value and polyphenol oxidase activity in apple slices decreased during the entire drying process, whereas other colour indexes, including CIE a, b, ΔE and C* values, increased. The browning ratio calculated by image analysis increased during the drying process, and a sharp increment was observed for the DIC process. The change in 5-hydroxymethylfurfural (5-HMF) and fluorescent compounds (FIC) showed the same trend with browning ratio due to Maillard reaction. Moreover, the concentrations of 5-HMF and FIC both had a good quadratic correlation (R 2 > 0.998) with the browning ratio. Browning ratio was a reliable indicator of 5-HMF and FIC changes in apple slices during drying. The image analysis system could be used to monitor colour changes, 5-HMF and FIC in dehydrated apple slices during the AD-DIC process. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry. 11. Influence of cold isostatic pressing on the magnetic properties of Ni-Zn-Cu ferrite Science.gov (United States) Le, Trong Trung; Valdez-Nava, Zarel; Lebey, Thierry; Mazaleyrat, Frédéric 2018-04-01 In power electronics, there is the need to develop solutions to increase the power density of converters. Interleaved multicellular transformers allow interleaving many switching cells and, as a result, a possible increase in the power density. This converter is often composed of a magnetic core having the function of an intercell transformer (ICT) and, depending on the complexity of the designed architecture, its shape could be extremely complex. The switching frequencies (1-10 MHz) for the new wide band gap semiconductors (SiC, GaN) allow to interleave switching cell at higher frequencies than silicon-based semiconductors (materials, but their limit in frequency drive raises the need of higher frequency magnetic materials, such Ni-Zn ferrites. These materials can operate in medium and high power converters up to 10 MHz. We propose to use Ni0,30Zn0,57Cu0,15Fe2O4 ferrite and to compress it by cold isostatic pressing (CIP) into a a green ceramic block and to machine it to obtain the desired ICT of complex shape prior sintering. We compare the magnetic permeability spectra and hysteresis loops the CIP and uniaxially pressed ferrites. The effect of temperature and sintering time as well as high-pressure on properties will be presented in detail. The magnetic properties of the sintered cores are strongly dependent on the microstructure obtained. 12. Factors influencing the creep strength of hot pressed beryllium International Nuclear Information System (INIS) Webster, D.; Crooks, D.D. 1975-01-01 The parameters controlling the creep strength of hot pressed beryllium block have been determined. Creep strength was improved by a high initial dislocation density, a coarse grain size, and a low impurity content. The impurities most detrimental to creep strength were found to be aluminum, magnesium, and silicon. A uniform distribution of BeO was found to give creep strength which was inferior to a grain boundary distribution. The creep strength of very high purity, hot isostatically pressed beryllium was found to compare favorably with that of other more commonly used high temperature metals 13. Vacuum hot pressing of titanium-alloy powders International Nuclear Information System (INIS) Malik, R.K. 1975-01-01 Full or nearly full dense products of wrought-metal properties have been obtained by vacuum hot pressing (VHP) of several prealloyed Ti--6Al--4V powders including hydride, hydride/dehydride, and rotating electrode process (REP) spherical powder. The properties of billets VHP from Ti--6Al--4V hydride powder and from hydride/dehydride powders have been shown to be equivalent. The REP spherical powder billets processed by VHP or by hot isostatic pressing (HIP) resulted in equivalent tensile properties. The potential of VHP for fabrication of near net aircraft parts such as complex fittings and engine disks offers considerable cost savings due to reduced material and machining requirements 14. HOT 2012 DEFF Research Database (Denmark) Lund, Henriette Romme Undersøgelse af, hvad der er hot - og hvad der burde være hot på læseområdet med 21 læsekyndige. Undersøgelsen er gennemført siden 2010. HOT-undersøgelsen er foretaget af Nationalt Videncenter for Læsning - Professionshøjskolerne i samarb. med Dansklærerforeningen......Undersøgelse af, hvad der er hot - og hvad der burde være hot på læseområdet med 21 læsekyndige. Undersøgelsen er gennemført siden 2010. HOT-undersøgelsen er foretaget af Nationalt Videncenter for Læsning - Professionshøjskolerne i samarb. med Dansklærerforeningen... 15. HOT 2014 DEFF Research Database (Denmark) Lund, Henriette Undersøgelse af, hvad der er hot - og hvad der burde være hot på læseområdet med 21 læsekyndige. Undersøgelsen er gennemført siden 2010. HOT-undersøgelsen er foretaget af Nationalt Videncenter for Læsning - Professionshøjskolerne i samarb. med Dansklærerforeningen... 16. HOT 2011 DEFF Research Database (Denmark) Lund, Henriette Romme En undersøgelse af, hvad der er hot - og burde være hot på læseområdet. I undersøgelsen deltager 21 læsekyndige fra praksisfeltet, professionshøjskolerne og forskningsområdet.......En undersøgelse af, hvad der er hot - og burde være hot på læseområdet. I undersøgelsen deltager 21 læsekyndige fra praksisfeltet, professionshøjskolerne og forskningsområdet.... 17. Worldwide complete spherical Bouguer and isostatic anomaly maps Science.gov (United States) Bonvalot, S.; Balmino, G.; Briais, A.; Peyrefitte, A.; Vales, N.; Biancale, R.; Gabalda, G.; Reinquin, F. 2011-12-01 We present here a set of digital maps of the Earth's gravity anomalies (surface "free air", Bouguer and isostatic), computed at Bureau Gravimetric International (BGI) as a contribution to the Global Geodetic Observing Systems (GGOS) and to the global geophysical maps published by the Commission for the Geological Map of the World (CGMW). The free air and Bouguer anomaly concept is extensively used in geophysical interpretation to investigate the density distributions in the Earth's interior. Complete Bouguer anomalies (including terrain effects) are usually computed at regional scales by integrating the gravity attraction of topography elements over and beyond a given area (under planar or spherical approximations). Here, we developed and applied a worldwide spherical approach aimed to provide a set of homogeneous and high resolution gravity anomaly maps and grids computed at the Earth's surface, taking into account a realistic Earth model and reconciling geophysical and geodetic definitions of gravity anomalies. This first version (1.0) has been computed by spherical harmonics analysis / synthesis of the Earth's topography-bathymetry up to degree 10800. The detailed theory of the spherical harmonics approach is given in Balmino et al., (Journal of Geodesy, submitted). The Bouguer and terrain corrections have thus been computed in spherical geometry at 1'x1' resolution using the ETOPO1 topography/bathymetry, ice surface and bedrock models from the NOAA (National Oceanic and Atmospheric Administration) and taking into account precise characteristics (boundaries and densities) of major lakes, inner seas, polar caps and of land areas below sea level. Isostatic corrections have been computed according to the Airy Heiskanen model in spherical geometry for a constant depth of compensation of 30km. The gravity information given here is provided by the Earth Geopotential Model (EGM2008), developed at degree 2160 by the National Geospatial Intelligence Agency (NGA) (Pavlis 18. Gravity and isostatic anomaly maps of Greece produced Science.gov (United States) Lagios, E.; Chailas, S.; Hipkin, R. G. A gravity anomaly map of Greece was first compiled in the early 1970s [Makris and Stavrou, 1984] from all available gravity data collected by different Hellenic institutions. However, to compose this map the data had to be smoothed to the point that many of the smaller-wavelength gravity anomalies were lost. New work begun in 1987 has resulted in the publication of an updated map [Lagios et al., 1994] and an isostatic anomaly map derived from it.The gravity data cover the area between east longitudes 19° and 27° and north latitudes 32° and 42°, organized in files of 100-km squares and grouped in 10-km squares using UTM zone 34 coordinates. Most of the data on land come from the gravity observations of Makris and Stavrou [1984] with additional data from the Institute of Geology and Mining Exploration, the Public Oil Corporation of Greece, and Athens University. These data were checked using techniques similar to those used in compiling the gravity anomaly map of the United States, but the horizontal gradient was used as a check rather than the gravity difference. Marine data were digitized from the maps of Morelli et al. [1975a, 1975b]. All gravity anomaly values are referred to the IGSN-71 system, reduced with the standard Bouger density of 2.67 Mg/m3. We estimate the errors of the anomalies in the continental part of Greece to be ±0.9 mGal; this is expected to be smaller over fairly flat regions. For stations whose height has been determined by leveling, the error is only ±0.3 mGal. For the marine areas, the errors are about ±5 mGal [Morelli, 1990]. 19. The alignment and isostatic mount bonding technique of the aerospace Cassegrain telescope primary mirror Science.gov (United States) Lin, Wei Cheng; Chang, Shenq-Tsong; Lin, Yu-Chuan; Hsu, Ming-Ying; Chang, Yu-Ting; Chang, Sheng-Hsiung; Huang, Ting-Ming 2012-10-01 In order to meet both optical performance and structural stiffness requirements of the aerospace Cassegrain telescope, iso-static mount is used as the interface between the primary mirror and the main plate. This article describes the alignment and iso-static mount bonding technique of the primary mirror by assistance of CMM. The design and assembly of mechanical ground support equipment (MGSE) which reduces the deformation of primary mirror by the gravity effect is also presented. The primary mirror adjusting MGSE consists of X-Y linear translation stages, rotation stage and kinematic constrain platform which provides the function of decenter, orientation, tilt and height adjustment of the posture sequentially. After CMM measurement, the radius of curvature, conic constant, decenter and tilt, etc. will be calculated. According to these results, the posture of the mirror will be adjusted to reduce the tilt by the designed MGSE within 0.02 degrees and the distance deviation from the best fitted profile of mirror to main plate shall be less than 0.01 mm. After that, EC 2216 adhesive is used to bond mirror and iso-static mount. During iso-static mount bonding process, CMM is selected to monitor the relative position deviation of the iso-static mount until the adhesive completely cured. After that, the wave front sensors and strain gauges are used to monitor the strain variation while the iso-static mount mounted in the main plate with the screws by the torque wrench. This step is to prevent deformation of the mirror caused from force of the iso-static mount during the mounting process. In the end, the interferometer is used for the optical performance test with +1G and -1G to check the alignment and bonding technique is well or not. 20. Characteristics of isostatic gravity anomaly in Sichuan-Yunnan region, China Directory of Open Access Journals (Sweden) Bingcheng Liu 2017-07-01 Full Text Available Sichuan-Yunnan region in China, a tectonic transition belt where earthquakes occurred frequently and intensely, has a distinct variation characteristic of gradient zone of Bouguer gravity anomaly (BGA. Many deep faults and epicenters of severe earthquake scatter along the BGA gradient zones. Here we apply two forward models (Airy model and Vening Meinesz model of isostatic gravity mechanisms (local versus regional in this region to calculated the isostatic gravity anomaly (IGA. Afterwards, the relationship between IGA and distribution of faults as well as seismicity is also illustrated. The IGA results show that the two models are similar and most parts of the study area are in an isostatic state. Most featured faults are distributed along the steep anomaly gradient zones; earthquakes tend to occur in the non-isostatic area and steep gradient belt of IGA. The distribution of root thickness based on regional mechanism can be associated with the main trend of BGA variation. The regional mechanism is more plausible and closer to the reality because of its relatively further consideration of the horizontal forces derived from adjacent particles in the crust. Then we analyze the effect of isostasy on the tectonic movements and find that the isostatic adjustment is not the main cause of the continuous uplift process of Longmenshan Mountain fault zone, which is due to the Indian-Eurasian continental collision. 1. Mechanical behavior of cellular borosilicate glass with pressurized Ar-filled closed pores International Nuclear Information System (INIS) Wang Bo; Matsumaru, Koji; Yang Jianfeng; Fu Zhengyi; Ishizaki, Kozo 2012-01-01 High strength borosilicate foams were fabricated by melting glass powder under high-pressure argon gas and subsequent heat treatment of the glass bulk at atmospheric pressure. In the first step, borosilicate glass powder was melted at 1100 °C for 1 h by capsule-free hot isostatic pressing (HIPing) under a high gas pressure of 10–70 MPa. Pressurized Ar-filled spherical pores were introduced into the glass, and argon atoms were dissolved in the glass network structure. The expansion of argon-filled pores and the release of the dissolved Ar gas resulted in the formation of pressurized Ar-filled closed pores by isothermal heat treatment at 800 °C for 10 min. A high porosity of up to 80% with a bimodal distribution of micro-size cells was obtained for the resultant cellular borosilicate glass. By increasing the total gas pressure from 10 to 70 MPa, the compressive strength and the Young’s modulus were increased considerably from 15 to 52 MPa and from 4.1 to 12.6 GPa, respectively, which can be substantially attributed to the high collapse stress from the high enclosed gas pressure. The cellular glass with a high porosity showed a large failure strain under uniaxial compression. 2. HOT 2010 DEFF Research Database (Denmark) Lund, Henriette Romme En undersøgelse af, hvad der er hot - og burde være hot på læseområdet. I undersøgelsen deltager en række læsekyndige fra praksisfeltet, professionshøjskolerne og forskningsområdet. Undersøgelsen er gentaget hvert år siden 2010.......En undersøgelse af, hvad der er hot - og burde være hot på læseområdet. I undersøgelsen deltager en række læsekyndige fra praksisfeltet, professionshøjskolerne og forskningsområdet. Undersøgelsen er gentaget hvert år siden 2010.... 3. HOT 2013 DEFF Research Database (Denmark) Lund, Henriette Romme En undersøgelse af, hvad der er hot - og burde være hot på læseområdet. I undersøgelsen deltager en række læsekyndige fra praksisfeltet, professionshøjskolerne og forskningsområdet. Undersøgelsen er gentaget hvert år siden 2010.......En undersøgelse af, hvad der er hot - og burde være hot på læseområdet. I undersøgelsen deltager en række læsekyndige fra praksisfeltet, professionshøjskolerne og forskningsområdet. Undersøgelsen er gentaget hvert år siden 2010.... 4. Influence of cold isostatic pressing on the magnetic properties of Ni-Zn-Cu ferrite Directory of Open Access Journals (Sweden) Trong Trung Le 2018-04-01 Full Text Available In power electronics, there is the need to develop solutions to increase the power density of converters. Interleaved multicellular transformers allow interleaving many switching cells and, as a result, a possible increase in the power density. This converter is often composed of a magnetic core having the function of an intercell transformer (ICT and, depending on the complexity of the designed architecture, its shape could be extremely complex. The switching frequencies (1-10 MHz for the new wide band gap semiconductors (SiC, GaN allow to interleave switching cell at higher frequencies than silicon-based semiconductors (<1 MHz. Intercell transformers must follow this increase in frequency times-fold the number of switching cells. Current applications for ICT transformers use Mn-Zn based materials, but their limit in frequency drive raises the need of higher frequency magnetic materials, such Ni-Zn ferrites. These materials can operate in medium and high power converters up to 10 MHz. We propose to use Ni0,30Zn0,57Cu0,15Fe2O4 ferrite and to compress it by cold isostatic pressing (CIP into a a green ceramic block and to machine it to obtain the desired ICT of complex shape prior sintering. We compare the magnetic permeability spectra and hysteresis loops the CIP and uniaxially pressed ferrites. The effect of temperature and sintering time as well as high-pressure on properties will be presented in detail. The magnetic properties of the sintered cores are strongly dependent on the microstructure obtained. 5. Tectonics and Non-isostatic Topography of the Mariana Trench and Adjacent Plates Science.gov (United States) Hongyu, L.; Lin, J.; Zhou, Z.; Zhang, F. 2017-12-01 Multi-types of geophysical data including multibeam bathymetry, sediment thickness, gravity anomaly, and crustal magnetic age were analyzed to investigate tectonic processes of the Mariana Trench and the surrounding plates. We calculated non-Airy-isostatic topography by removing from the observed bathymetry the effects of sediment loading, thermal subsidence, and Airy local isostatically-compensated topography. The Mariana Trench was found to be associated with a clearly defined zone of negative non-isostatic topography, which was caused by flexural bending of the subducting Pacific plate and with the maximum depth anomaly and flexural bending near the Challenger Deep. In contrast, the Caroline Ridge and Caroline Islands Chain have much more subdued non-isostatic topography, indicating their higher topography is largely compensated by thicker crust. Along the Mariana Trough, the northern and central segments appear to be associated with relatively low magma supply as indicated by the relatively low topography and thin crust. In contrast, the southern Mariana Trough is associated with relatively high magma supply as indicated by the relatively high and smoother topography, an axial high spreading center, and relatively thick crust. The southern end of the Mariana Trough was also found to be associated with positive non-isostatic topographic anomaly, which might be caused by the complex tectonic deformation of the overriding Mariana and Philippine Sea plates and their interaction with the subducting Pacific plate. Analysis further revealed that the southern Mariana Arc, located between the Mariana Trench and Mariana Trough, is associated with positive non-isostatic topographic anomalies, which may be explained by the late stage magmatic loading on the older and thus stronger lithospheric plate of the Mariana volcanic arc. 6. Absolute sea levels and isostatic changes of the eastern North Sea to central Baltic region during the last 900 years DEFF Research Database (Denmark) Hansen, Jens Morten; Aagaard, Troels; Binderup, Merete 2012-01-01 that ice-cap growth can be faster than ice-cap melting. By comparison with 29 long-term tide gauge measurements of the region we show that the isostatic implications of the sea-level curve are in nearly perfect agreement with Peltier's global isostatic VM2 model (applied by IPCC and PSMSL) and yield a 3... 7. A spatial analysis of population dynamics and climate change in Africa: potential vulnerability hot spots emerge where precipitation declines and demographic pressures coincide Science.gov (United States) López-Carr, David; Pricope, Narcisa G.; Aukema, Juliann E.; Jankowska, Marta M.; Funk, Christopher C.; Husak, Gregory J.; Michaelsen, Joel C. 2014-01-01 We present an integrative measure of exposure and sensitivity components of vulnerability to climatic and demographic change for the African continent in order to identify “hot spots” of high potential population vulnerability. Getis-Ord Gi* spatial clustering analyses reveal statistically significant locations of spatio-temporal precipitation decline coinciding with high population density and increase. Statistically significant areas are evident, particularly across central, southern, and eastern Africa. The highly populated Lake Victoria basin emerges as a particularly salient hot spot. People located in the regions highlighted in this analysis suffer exceptionally high exposure to negative climate change impacts (as populations increase on lands with decreasing rainfall). Results may help inform further hot spot mapping and related research on demographic vulnerabilities to climate change. Results may also inform more suitable geographical targeting of policy interventions across the continent. 8. Towards Constraining Glacial Isostatic Adjustment in Greenland Using ICESat and GPS Observations DEFF Research Database (Denmark) Nielsen, Karina; Sørensen, Louise Sandberg; Khan, Shfaqat Abbas 2014-01-01 Constraining glacial isostatic adjustment (GIA) i.e. the Earth’s viscoelastic response to past ice changes, is an important task, because GIA is a significant correction in gravity-based ice sheet mass balance estimates. Here, we investigate how temporal variations in the observed and modeled cru... 9. Isostatic gravity map of the Point Sur 30 x 60 quadrangle and adjacent areas, California Science.gov (United States) Watt, J.T.; Morin, R.L.; Langenheim, V.E. 2011-01-01 This isostatic residual gravity map is part of a regional effort to investigate the tectonics and water resources of the central Coast Range. This map serves as a basis for modeling the shape of basins and for determining the location and geometry of faults in the area. Local spatial variations in the Earth's gravity field (after removing variations caused by instrument drift, earth-tides, latitude, elevation, terrain, and deep crustal structure), as expressed by the isostatic anomaly, reflect the distribution of densities in the mid- to upper crust, which in turn can be related to rock type. Steep gradients in the isostatic gravity field often indicate lithologic or structural boundaries. Gravity highs reflect the Mesozoic granitic and Franciscan Complex basement rocks that comprise both the northwest-trending Santa Lucia and Gabilan Ranges, whereas gravity lows in Salinas Valley and the offshore basins reflect the thick accumulations of low-density alluvial and marine sediment. Gravity lows also occur where there are thick deposits of low-density Monterey Formation in the hills southeast of Arroyo Seco (>2 km, Marion, 1986). Within the map area, isostatic residual gravity values range from approximately -60 mGal offshore in the northern part of the Sur basin to approximately 22 mGal in the Santa Lucia Range. 10. Modification of low density polyethylene, isostatic polypropylene and their blends by gamma radiation International Nuclear Information System (INIS) Santos Rosa, D. dos 1991-01-01 The effects of the gamma radiation (of a 60 Co source), over low density polyethylene, isostatic polypropylene and their blends of low density polyethylene / polypropylene were studied. The structures modifications were attended by infrared spectrometry (IV), differential scanning calorimeter (DSC), strain-strain measurement, density measurement and scanning electron microscope (SEM). (author) 11. An empirical model of glacio-isostatic movements and shore-level displacement in Fennoscandia Energy Technology Data Exchange (ETDEWEB) Paasse, T. [Geological Survey of Sweden, Uppsala (Sweden) 2001-08-01 Shore-level displacement in Fennoscandia is mainly due to two co-operative vertical movements, glacio-isostatic uplift and global eustatic sea level rise. The course of the glacio-isostatic uplift has been made discernible according to an investigation of the lake-tilting phenomenon. This information made it possible to start an iteration process that has given mathematical expression for factors involved both within the isostatic movements and the eustatic rise. There are two components involved in glacio-isostatic uplift. The main uplift, still in progress, acts slowly and is thus called the slow component. Arctan functions have proved to be suitable tools for describing the slow component. There are two main factors involved in the function used for calculation; A{sub s} (m), the download factor and B{sub s} (y{sup -1} ), which is an inertia factor. A strong linear correlation between the inertia factor Bs and lithosphere thickness has been found in the model. There was also a fast component involved in the crustal changes at the end of Late Weichselian and early Holocene. This component gave rise to fast subsidence followed by fast uplift during the final part of the deglaciation. Crustal subsidence is assumed to be due to reloading of the crust in the central parts of Fennoscandia during the Younger Dryas stadial. Normal distribution functions are used for calculating this component. Glacio-isostatic uplift and thus a regressive shore-level displacement was extremely rapid around 10,300 years BP. This fast regression was contemporaneous and occurred in a similar way at the West Coasts of Norway and Sweden as well as in the Baltic. The 'drainage' of the Baltic Ice Lake has been interpreted in the model as due to this fast regression. The slow component is most probably due to viscous flow in the asthenosphere and the fast component is assumed to be due to its elasticity. 12. An empirical model of glacio-isostatic movements and shore-level displacement in Fennoscandia International Nuclear Information System (INIS) Paasse, T. 2001-08-01 Shore-level displacement in Fennoscandia is mainly due to two co-operative vertical movements, glacio-isostatic uplift and global eustatic sea level rise. The course of the glacio-isostatic uplift has been made discernible according to an investigation of the lake-tilting phenomenon. This information made it possible to start an iteration process that has given mathematical expression for factors involved both within the isostatic movements and the eustatic rise. There are two components involved in glacio-isostatic uplift. The main uplift, still in progress, acts slowly and is thus called the slow component. Arctan functions have proved to be suitable tools for describing the slow component. There are two main factors involved in the function used for calculation; A s (m), the download factor and B s (y -1 ), which is an inertia factor. A strong linear correlation between the inertia factor Bs and lithosphere thickness has been found in the model. There was also a fast component involved in the crustal changes at the end of Late Weichselian and early Holocene. This component gave rise to fast subsidence followed by fast uplift during the final part of the deglaciation. Crustal subsidence is assumed to be due to reloading of the crust in the central parts of Fennoscandia during the Younger Dryas stadial. Normal distribution functions are used for calculating this component. Glacio-isostatic uplift and thus a regressive shore-level displacement was extremely rapid around 10,300 years BP. This fast regression was contemporaneous and occurred in a similar way at the West Coasts of Norway and Sweden as well as in the Baltic. The 'drainage' of the Baltic Ice Lake has been interpreted in the model as due to this fast regression. The slow component is most probably due to viscous flow in the asthenosphere and the fast component is assumed to be due to its elasticity 13. Theory of hot particle stability International Nuclear Information System (INIS) Berk, H.L.; Wong, H.V.; Tsang, K.T. 1986-10-01 The investigation of stabilization of hot particle drift reversed systems to low frequency modes has been extended to arbitrary hot beta, β/sub H/ for systems that have unfavorable field line curvature. We consider steep profile equilibria where the thickness of the pressure drop, Δ, is less than plasma radius, r/sub p/. The analysis describes layer modes which have mΔ/r/sub p/ 2/3. When robust stability conditions are fulfilled, the hot particles will have their axial bounce frequency less than their grad-B drift frequency. This allows for a low bounce frequency expansion to describe the axial dependence of the magnetic compressional response 14. Suppression of sawtooth oscillations due to hot electrons and hot ions International Nuclear Information System (INIS) Zhang, Y.Z.; Berk, H.L. 1989-01-01 The theory of m = 1 kink mode stabilization is discussed in the presence of either magnetically trapped hot electrons or hot ions. For instability hot ion requires particles peaked inside the q = 1 surface, while hot electrons require that its pressure profile be increasing at the q = 1 surface. Experimentally observed sawtooth stabilization usually occurs with off-axis heating with ECRH and near axis heating with ICRH. Such heating may produce the magnetically trapped hot particle pressure profiles that are consistent with theory. 17 refs., 2 figs 15. Isostatic anomaly characteristics and dynamic environment of New Britain Ocean trenches and neighboring Area in Papua New Guinea Science.gov (United States) Yang, G.; Shen, C.; Wang, J. 2017-12-01 we calculated the Bouguer gravity anomaly and the Airy-Heiskanen isostatic anomaly in the New Britain ocean trenches and its surrounding areas of Papua New Guinea using the topography model and the gravity anomaly model from Scripps Institute of Oceanography, and analyzed the characteristics of isostatic anomaly and the earthquake dynamic environment of this region. The results show that there are obviously differences in the isostatic state between each block in the region, and the crustal tectonic movement is very intense in the regions with high positive or negative isostatic gravity anomalies; A number of sub-plates in this area is driven by the external tectonic action such as plate subduction and thrust of the Pacific plate, the Indian - Australian plate and the Eurasian plate. From the distribution of isostatic gravity anomaly, the tectonic action of anti-isostatic movement in this region is the main source of power; from the isostatic gravity and the spatial distribution of the earthquake, with the further contraction of the Indian-Australian plate, the southwestern part of the Solomon Haiya plate will become part of the Owen Stanley fold belt, the northern part will enter the lower part of the Bismarck plate, eastern part will enter the front of the Pacific plate, the huge earthquake will migrate to the north and east of the Solomon Haiya plate. 16. HOT 2017 DEFF Research Database (Denmark) Hannibal, Sara Stefansen HOT er en kvalitativ undersøgelse, der hvert år diskuterer og undersøger en lille udvalgt skare af danskkyndige fagpersoners bud på, hvad de er optagede af på literacyområdet her og nu – altså hvilke emner, de vil vurdere som aktuelle at forholde sig til i deres nuværende praksis.......HOT er en kvalitativ undersøgelse, der hvert år diskuterer og undersøger en lille udvalgt skare af danskkyndige fagpersoners bud på, hvad de er optagede af på literacyområdet her og nu – altså hvilke emner, de vil vurdere som aktuelle at forholde sig til i deres nuværende praksis.... 17. Hot particles International Nuclear Information System (INIS) Merwin, S.E.; Moeller, M.P. 1989-01-01 Nuclear Regulatory Commission (NRC) licensees are required to assess the dose to skin from a hot particle contamination event at a depth of skin of7mg/cm 2 over an area of 1 cm 2 and compare the value to the current dose limit for the skin. Although the resulting number is interesting from a comparative standpoint and can be used to predict local skin reactions, comparison of the number to existing limits based on uniform exposures is inappropriate. Most incidents that can be classified as overexposures based on this interpretation of dose actually have no effect on the health of the worker. As a result, resources are expended to reduce the likelihood that an overexposure event will occur when they could be directed toward eliminating the cause of the problem or enhancing existing programs such as contamination control. Furthermore, from a risk standpoint, this practice is not ALARA because some workers receive whole body doses in order to minimize the occurrence of hot particle skin contaminations. In this paper the authors suggest an alternative approach to controlling hot particle exposures 18. Utilizing Visual Effects Software for Efficient and Flexible Isostatic Adjustment Modelling Science.gov (United States) Meldgaard, A.; Nielsen, L.; Iaffaldano, G. 2017-12-01 The isostatic adjustment signal generated by transient ice sheet loading is an important indicator of past ice sheet extent and the rheological constitution of the interior of the Earth. Finite element modelling has proved to be a very useful tool in these studies. We present a simple numerical model for 3D visco elastic Earth deformation and a new approach to the design of such models utilizing visual effects software designed for the film and game industry. The software package Houdini offers an assortment of optimized tools and libraries which greatly facilitate the creation of efficient numerical algorithms. In particular, we make use of Houdini's procedural work flow, the SIMD programming language VEX, Houdini's sparse matrix creation and inversion libraries, an inbuilt tetrahedralizer for grid creation, and the user interface, which facilitates effortless manipulation of 3D geometry. We mitigate many of the time consuming steps associated with the authoring of efficient algorithms from scratch while still keeping the flexibility that may be lost with the use of commercial dedicated finite element programs. We test the efficiency of the algorithm by comparing simulation times with off-the-shelf solutions from the Abaqus software package. The algorithm is tailored for the study of local isostatic adjustment patterns, in close vicinity to present ice sheet margins. In particular, we wish to examine possible causes for the considerable spatial differences in the uplift magnitude which are apparent from field observations in these areas. Such features, with spatial scales of tens of kilometres, are not resolvable with current global isostatic adjustment models, and may require the inclusion of local topographic features. We use the presented algorithm to study a near field area where field observations are abundant, namely, Disko Bay in West Greenland with the intention of constraining Earth parameters and ice thickness. In addition, we assess how local 19. Fabrication and characterization of powder metallurgy tantalum components prepared by high compaction pressure technique Energy Technology Data Exchange (ETDEWEB) Kim, Youngmoo [Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141 (Korea, Republic of); Agency for Defense Development, Yuseong, P.O. Box 35, Yuseong-gu, Daejeon 34186, Republic of Korea. (Korea, Republic of); Lee, Dongju [Korea Atomic Energy Research Institute, 111 Daedeok-daero, Yuseong-gu, Daejeon 34057 (Korea, Republic of); Hwang, Jaewon [Samsung Electronics, 129 Samsung-ro, Youngtong-gu, Suwon 16677 (Korea, Republic of); Ryu, Ho Jin, E-mail: [email protected] [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141 (Korea, Republic of); Hong, Soon Hyung, E-mail: [email protected] [Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141 (Korea, Republic of) 2016-04-15 The present study has investigated the consolidation behaviors of tantalum powders during compaction and sintering, and the characteristics of sintered components. For die compaction, the densification behaviors of the powders are simulated by finite element analyses based on the yield function proposed by Shima and Oyane. Accordingly, the green density distribution for coarser particles is predicted to be more uniform because they exhibits higher initial relative tap density owing to lower interparticle friction. It is also found that cold isostatic pressing is capable of producing higher dense compacts compared to the die pressing. However, unlike the compaction behavior, the sintered density of smaller particles is found to be higher than those of coarser ones owing to their higher specific surface area. The maximum sintered density was found to be 0.96 of theoretical density where smaller particles were pressed isostatically at 400 MPa followed by sintering at 2000 °C. Moreover, the effects of processing conditions on grain size and texture were also investigated. The average grain size of the sintered specimen is 30.29 μm and its texture is less than 2 times random intensity. Consequently, it is concluded that the higher pressure compaction technique is beneficial to produce high dense and texture-free tantalum components compared to hot pressing and spark plasma sintering. - Highlights: • Higher Ta density is obtained from higher pressure and sintering temperature. • High compaction method enables P/M Ta to achieve the density of 16.00 g·cm{sup −3}. • A P/M Ta component with fine microstructure and random orientation is developed. 20. PM-HIP research for structural and pressuring retaining applications within the electric power industry International Nuclear Information System (INIS) Gandy, David W. 2015-01-01 For more than 60 years now, the nuclear power industry has relied on structural and pressure retaining materials generated via established manufacturing practices such as casting, plate rolling-and-welding, forging, drawing, and/or extrusion. During the past three years, EPRI has been leading the development and introduction of another established process, powder metallurgy and hot Isostatic pressing (PM/HIP), for pressure retaining applications in electric power industry. The research includes assessment of two primary alloys: 316L stainless steel and Grade 91 creep-strength enhanced ferritic steels, for introduction into the ASME Boiler and Pressure Vessel Code. Continuing DOE and EPRI research on other structural/pressure retaining alloys such as Alloy 690, SA 508 Class 1, Alloy 625, hard-facing materials, and others are also underway. This research will have a tremendous impact as we move forward over the next few decades on the selection of new alloys and components for advanced light water reactors and small modular reactors. Furthermore, fabrication of high alloy materials/components may require the use of new manufacturing processes to achieve acceptable properties for higher temperature applications such as those in Generation IV applications. Current research by EPRI and DOE will be reviewed and emphasis will be targeted at advanced applications where PM/HIP may be applied in the future. (authors) 1. Influence of HIP pressure on tensile properties of a 14Cr ODS ferritic steel Energy Technology Data Exchange (ETDEWEB) Oksiuta, Z., E-mail: [email protected] [Bialystok Technical University, Mechanical Department, Wiejska 45c, 15-351 Bialystok (Poland); Ozieblo, A.; Perkowski, K.; Osuchowski, M. [Institute of Ceramics and Building Materials, Postępu 9, 02-676 Warsaw (Poland); Lewandowska, M. [Warsaw University of Technology, Woloska 141, 02-504 Warsaw (Poland) 2014-02-15 Highlights: • The HIPping parameters of the 14Cr–2W–0.3Ti–0.3Y{sub 2}O{sub 3} ODS steel powder were investigated. • The density and microstructure of the tested specimens after HIPping were studied. • The mechanical properties, high temperature tensile tests, were performed. • Residual porosity was observed in all tested specimens. • HIPping pressure has negligible influence on the strength of the ODS steel however improves material ductility. - Abstract: An oxide dispersion strengthened ferritic steel with a nominal composition of Fe–14Cr–2W–0.3Ti–0.3Y{sub 2}O{sub 3} (in wt.%) was consolidated by hot isostatic pressing at 1150 °C under various pressures in the range of 185–300 MPa for 3 h. The microstructure, microhardness and high temperature tensile properties of the steel were investigated. With increasing compaction pressure the density of specimens also increased, however OM and SEM observations revealed residual porosity in all tested specimens and similar ferritic microstructure with bimodal-like grains and numerous of large oxide particles, located at the grain boundaries. Mechanical testing revealed that compaction pressure has negligible influence on the hardness and tensile strength of the ODS steel, however improves the material ductility. 2. Influence of HIP pressure on tensile properties of a 14Cr ODS ferritic steel International Nuclear Information System (INIS) Oksiuta, Z.; Ozieblo, A.; Perkowski, K.; Osuchowski, M.; Lewandowska, M. 2014-01-01 Highlights: • The HIPping parameters of the 14Cr–2W–0.3Ti–0.3Y 2 O 3 ODS steel powder were investigated. • The density and microstructure of the tested specimens after HIPping were studied. • The mechanical properties, high temperature tensile tests, were performed. • Residual porosity was observed in all tested specimens. • HIPping pressure has negligible influence on the strength of the ODS steel however improves material ductility. - Abstract: An oxide dispersion strengthened ferritic steel with a nominal composition of Fe–14Cr–2W–0.3Ti–0.3Y 2 O 3 (in wt.%) was consolidated by hot isostatic pressing at 1150 °C under various pressures in the range of 185–300 MPa for 3 h. The microstructure, microhardness and high temperature tensile properties of the steel were investigated. With increasing compaction pressure the density of specimens also increased, however OM and SEM observations revealed residual porosity in all tested specimens and similar ferritic microstructure with bimodal-like grains and numerous of large oxide particles, located at the grain boundaries. Mechanical testing revealed that compaction pressure has negligible influence on the hardness and tensile strength of the ODS steel, however improves the material ductility 3. Study of pore closure during pressure-less sintering of advanced oxide ceramics Czech Academy of Sciences Publication Activity Database Spusta, T.; Svoboda, Jiří; Maca, K. 2016-01-01 Roč. 115, AUG (2016), s. 347-353 ISSN 1359-6454 R&D Projects: GA ČR(CZ) GA15-06390S Institutional support: RVO:68081723 Keywords : Ceramic material * Sintering * Porosity * Modelling * Hot isostatic pressing Subject RIV: BJ - Thermodynamics Impact factor: 5.301, year: 2016 4. Production of glass or glass-ceramic to metal seals with the application of pressure Science.gov (United States) Kelly, Michael D.; Kramer, Daniel P. 1987-11-10 In a process for preparing a glass or glass-ceramic to metal seal comprising contacting the glass with the metal and heat-treating the glass and metal under conditions whereby the glass to metal seal is effected and, optionally, the glass is converted to a glass-ceramic, an improvement comprises carrying out the heat-treating step using hot isostatic pressing. 5. Hot isostatic pressing of single-crystal nickel-base superalloys: Mechanism of pore closure and effect on Mechanical properties Directory of Open Access Journals (Sweden) Epishin Alexander I. 2014-01-01 Full Text Available Pore annihilation was investigated in the single-crystal nickel-base superalloy CMSX-4. HIP tests at 1288 °C/103 MPa were interrupted at different times, then the specimens were investigated by TEM, metallography and density measurements. The kinetics of pore annihilation was determined. The pore closure mechanism was identified as plastic deformation on the octahedral slip systems. A model describing the kinetics of pore closure has been developed on the base of crystal plasticity and large strain theory. Mechanical tests with the superalloy CMSX-4 and the Ru-containing superalloy VGM4 showed, that HIP significantly increases the fatigue life at low temperatures but has no effect on creep strength. 6. La{sub 2}O{sub 3}-reinforced W and W-V alloys produced by hot isostatic pressing Energy Technology Data Exchange (ETDEWEB) Munoz, A., E-mail: [email protected] [Departamento de Fisica, Universidad Carlos III de Madrid, 28911 Leganes (Spain); Monge, M.A., E-mail: [email protected] [Departamento de Fisica, Universidad Carlos III de Madrid, 28911 Leganes (Spain); Savoini, B., E-mail: [email protected] [Departamento de Fisica, Universidad Carlos III de Madrid, 28911 Leganes (Spain); Rabanal, M.E., E-mail: [email protected] [Departamento de Ciencia e Ingenieria de Materiales e Ingenieria Quimica, Universidad Carlos III de Madrid, 28911 Leganes (Spain); Garces, G., E-mail: [email protected] [Centro Nacional de Investigaciones Melaturgicas, CENIM, 28040 Madrid (Spain); Pareja, R., E-mail: [email protected] [Departamento de Fisica, Universidad Carlos III de Madrid, 28911 Leganes (Spain) 2011-10-01 W and W-V alloys reinforced with La{sub 2}O{sub 3} particles have been produced by MA and subsequent HIP at 1573 K and 195 MPa. The microstructure of the consolidated alloys has been characterized by scanning electron microscopy, energy dispersive spectroscopy analyses and X-ray diffraction. The mechanical properties were studied by nanoindentation measurements. The results show that practically full dense billets of W-V, W-V-La{sub 2}O{sub 3} and W-La{sub 2}O{sub 3} alloys can be produced. The microstructure analysis has shown that islands of V are present in W-V and W-V-1La{sub 2}O{sub 3} alloys. In W-1La{sub 2}O{sub 3} islands of La{sub 2}O{sub 3} are also present. The nanohardness of the W matrix increases with the addition of V, while decreases with the addition of La{sub 2}O{sub 3}. 7. Effect of hot isostatic pressing temperature on the microstructural and mechanical properties in the mullite-zirconia composites International Nuclear Information System (INIS) Greca, M.C.G.; Melo, M. de F. 1990-01-01 This work studies the densification, the microstrutural evolution (porosity and zirconia grain size) and bending strength (σ f ) of the two mullite-zirconia composites with TiO 2 additions (0.25 and 1,0 mole%) submitted to different kind of hipping cycles at several temperatures. The results have been shown that: i) HIPing temperature seem to have no influence in densification and mechanical behaviour. ii) Total densification only appears in composition with more quantity of titania (1.0 mole%) which prove that titanium enhance the mass transfer by changes in grain boundary microchemistry. iii) Mechanical behaviour is correlated with densification and microstructural evolution for both composites and degradation is present at 1500 0 C and 1550 0 C which is related with particle coarsening. (author) [pt 8. Prediction of maximum casting defect size in MAR-M-247 alloy processed by hot isostatic pressing Czech Academy of Sciences Publication Activity Database Šmíd, Miroslav; Fintová, Stanislava; Kunz, Ludvík; Hutař, Pavel; Hrbáček, K. 2015-01-01 Roč. 22, č. 1 (2015), s. 25-32 ISSN 1335-0803 R&D Projects: GA MPO FR-TI4/030; GA MŠk(CZ) EE2.3.20.0214 Institutional support: RVO:68081723 Keywords : MAR-M 247 * Superalloys * Fatigue * Casting defects * Elevated temperatures Subject RIV: JL - Materials Fatigue, Friction Mechanics http://ojs.mateng.sk/index.php/Mateng/article/view/160/249 9. The Manufacture of W-UO2 Fuel Elements for NTP Using the Hot Isostatic Pressing Consolidation Process Science.gov (United States) Broadway, Jeramie; Hickman, Robert; Mireles, Omar 2012-01-01 NTP is attractive for space exploration because: (1) Higher Isp than traditional chemical rockets (2)Shorter trip times (3) Reduced propellant mass (4) Increased payload. Lack of qualified fuel material is a key risk (cost, schedule, and performance). Development of stable fuel form is a critical path, long lead activity. Goals of this project are: Mature CERMET and Graphite based fuel materials and Develop and demonstrate critical technologies and capabilities. 10. Progress in hot pressing International Nuclear Information System (INIS) Brodhag, C.; Thevenot, F. 1988-01-01 An experimental technique is described to study hot pressing of ceramics under conditions of controlled temperature and pressure during both the heating and final sintering stages. This method gives a better control of the final microstructure of the material. Transformation mechanisms can be studied during initial heating stage (impurity degasing, reaction, phase transformation, mechanical behavior of intergranular phase...) using computer control and graphical data representations. Some examples will be given for different systems studied in our laboratory: B (α, β, amorphous), B 12 O 2 (reaction of B + B 2 O 3 ), Si 3 N 4 ( + additives), TiN, Al 2 O 3 + AlON,ZrC 11. Promethus Hot Leg Piping Concept International Nuclear Information System (INIS) AM Girbik; PA Dilorenzo 2006-01-01 The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept 12. Fundamental properties of monolithic bentonite buffer material formed by cold isostatic pressing for high-level radioactive waste repository International Nuclear Information System (INIS) Kawakami, S.; Yamanaka, Y.; Kato, K.; Asano, H.; Ueda, H. 1999-01-01 The methods of fabrication, handling, and emplacement of engineered barriers used in a deep geological repository for high level radioactive waste should be planned as simply as possible from the engineering and economic viewpoints. Therefore, a new concept of a monolithic buffer material around a waste package have been proposed instead of the conventional concept with the use of small blocks, which would decrease the cost for buffer material. The monolithic buffer material is composed of two parts of highly compacted bentonite, a cup type body and a cover. As the forming method of the monolithic buffer material, compaction by the cold isostatic pressing process (CIP) has been employed. In this study, monolithic bentonite bodies with the diameter of about 333 mm and the height of about 455 mm (corresponding to the approx. 1/5 scale for the Japanese reference concept) were made by the CIP of bentonite powder. The dry densities: ρd of the bodies as a whole were measured and the small samples were cut from several locations to investigate the density distribution. The swelling pressure and hydraulic conductivity as function of the monolithic body density for CIP-formed specimens were also measured. High density (ρd: 1.4--2.0 Mg/m 3 ) and homogeneous monolithic bodies were formed by the CIP. The measured results of the swelling pressure (3--15 MPa) and hydraulic conductivity (0.5--1.4 x 10 -13 m/s) of the specimens were almost the same as those for the uniaxial compacted bentonite in the literature. It is shown that the vacuum hoist system is an applicable handling method for emplacement of the monolithic bentonite 13. Determination of diffusion coefficients of hydrogen and deuterium in Zr–2.5%Nb pressure tube material using hot vacuum extraction-quadrupole mass spectrometry Energy Technology Data Exchange (ETDEWEB) Shrivastava, Komal Chandra, E-mail: [email protected] [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Kulkarni, A.S.; Ramanjaneyulu, P.S. [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Sunil, Saurav [Mechanical Metallurgy Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Saxena, M.K. [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Singh, R.N. [Mechanical Metallurgy Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Tomar, B.S.; Ramakumar, K.L. [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India) 2015-06-15 The diffusion coefficients of hydrogen and deuterium in Zr–2.5%Nb alloy were measured in the temperature range 523 to 673 K, employing hot vacuum extraction-quadrupole mass spectrometry (HVE-QMS). One end of the Zr–2.5%Nb alloy specimens was charged electrolytically with the desired hydrogen isotope. After annealing at different temperatures for a predetermined time, the specimens were cut into thin slices, which were analyzed for their H{sub 2}/D{sub 2} content using the HVE-QMS technique. The depth profile data were fitted into the equation representing the solution of Fick’s second law of diffusion. The activation energy of hydrogen/deuterium diffusion was obtained from the Arrhenius relation between the diffusion coefficient and temperature. The temperature dependent diffusion coefficient can be represented as D{sub H} = 1.41 × 10{sup −7} exp(−36,000/RT) and D{sub D} = 6.16 × 10{sup −8} exp(−35,262/RT) for hydrogen and deuterium, respectively. 14. Hot dry rock heat mining International Nuclear Information System (INIS) Duchane, D.V. 1992-01-01 Geothermal energy utilizing fluids from natural sources is currently exploited on a commercial scale at sites around the world. A much greater geothermal resource exists, however, in the form of hot rock at depth which is essentially dry. This hot dry rock (HDR) resource is found almost everywhere, but the depth at which usefully high temperatures are reached varies from place to place. The technology to mine the thermal energy from HDR has been under development for a number of years. Using techniques adapted from the petroleum industry, water is pumped at high pressure down an injection well to a region of usefully hot rock. The pressure forces open natural joints to form a reservoir consisting of a small amount of water dispensed in a large volume of hot rock. This reservoir is tapped by second well located at some distance from the first, and the heated water is brought to the surface where its thermal energy is extracted. The same water is then recirculated to mine more heat. Economic studies have indicated that it may be possible to produce electricity at competitive prices today in regions where hot rock is found relatively close to the surface 15. Analysis of a hot-leg small break loss-of-coolant accident in a three-loop westinghouse pressurized water reactor plant International Nuclear Information System (INIS) Peterson, C.E.; Chexal, V.K.; Clements, T.B. 1985-01-01 The RETRAN-02 computer code was used to perform a best-estimate analysis of a 7.52-cm-diam hotleg break in a three-loop Westinghouse pressurized water reactor. This break size produced a net primary coolant mass depletion through the early portion of the transient. The primary system started to refill only after the accumulator valves opened. As the primary system refilled, there were extreme temperature differentials around the system with cold, denser fluid collecting at the lower elevations and two-phase fluid at higher elevations 16. Isostatic Implications of Different Seismic and Gravity Derived Moho Depths for Antarctica Science.gov (United States) Ferraccioli, F.; Pappa, F.; Ebbing, J. 2017-12-01 Several studies with different methods have been performed to investigate the lithospheric structure of Antarctica, in particular the Moho as the crust-mantle boundary. Yet, seismological surveys are regionally limited or suffer from sparse station coverage due to the remoteness and size of the continent. On the other hand, gravity studies are inherently ambiguous and therefore not able to determine both the geometry and the density contrast of the Moho. Existing Moho depth models for Antarctica show large discrepancies, even among different seismological methods, but all the more between seismological and gravity models. As a first step towards a possible reconcilement, we perform non-linear gravity inversions with simultaneous consideration of seismological data. Depending on the seismological input data, different depths and density contrasts yield the best fit. The results, however, are not in line with the pure seismological models. Subsequently, we compute simple Airy-isostatic Moho depth models and evaluate these together with multiple Moho models from previous studies in terms of their gravitational signal, applying different values for the density contrast. The models' responses are checked against observational data: vertical gravity at 50 km altitude from the spherical harmonics expansion model GOCO05s, and the gravity gradient tensor at 225 km altitude from the GOCE gravity gradient grids. While the gravity responses from the seismological models show strong disagreements with the data, the Airy-isostatic models fit better. Yet, differences of up to 10 km in depth exist between the isostatic and the gravity-inverted Moho models. From these differences in vertical gravity, in the gravity gradients and in Moho depth, we identify regions where a simple density contrast is not sufficient to explain the observed gravitational field. We conclude that lateral and vertical density variations must be considered, which might originate from high-density lower 17. The Distinction of Hot Herbal Compress, Hot Compress, and Topical Diclofenac as Myofascial Pain Syndrome Treatment. Science.gov (United States) Boonruab, Jurairat; Nimpitakpong, Netraya; Damjuti, Watchara 2018-01-01 This randomized controlled trial aimed to investigate the distinctness after treatment among hot herbal compress, hot compress, and topical diclofenac. The registrants were equally divided into groups and received the different treatments including hot herbal compress, hot compress, and topical diclofenac group, which served as the control group. After treatment courses, Visual Analog Scale and 36-Item Short Form Health survey were, respectively, used to establish the level of pain intensity and quality of life. In addition, cervical range of motion and pressure pain threshold were also examined to identify the motional effects. All treatments showed significantly decreased level of pain intensity and increased cervical range of motion, while the intervention groups exhibited extraordinary capability compared with the topical diclofenac group in pressure pain threshold and quality of life. In summary, hot herbal compress holds promise to be an efficacious treatment parallel to hot compress and topical diclofenac. 18. Extensional Fault Evolution and its Flexural Isostatic Response During Iberia-Newfoundland Rifted Margin Formation Science.gov (United States) Gómez-Romeu, J.; Kusznir, N.; Manatschal, G.; Roberts, A. 2017-12-01 During the formation of magma-poor rifted margins, upper lithosphere thinning and stretching is achieved by extensional faulting, however, there is still debate and uncertainty how faults evolve during rifting leading to breakup. Seismic data provides an image of the present-day structural and stratigraphic configuration and thus initial fault geometry is unknown. To understand the geometric evolution of extensional faults at rifted margins it is extremely important to also consider the flexural response of the lithosphere produced by fault displacement resulting in footwall uplift and hangingwall subsidence. We investigate how the flexural isostatic response to extensional faulting controls the structural development of rifted margins. To achieve our aim, we use a kinematic forward model (RIFTER) which incorporates the flexural isostatic response to extensional faulting, crustal thinning, lithosphere thermal loads, sedimentation and erosion. Inputs for RIFTER are derived from seismic reflection interpretation and outputs of RIFTER are the prediction of the structural and stratigraphic consequences of recursive sequential faulting and sedimentation. Using RIFTER we model the simultaneous tectonic development of the Iberia-Newfoundland conjugate rifted margins along the ISE01-SCREECH1 and TGS/LG12-SCREECH2 seismic lines. We quantitatively test and calibrate the model against observed target data restored to breakup time. Two quantitative methods are used to obtain this target data: (i) gravity anomaly inversion which predicts Moho depth and continental lithosphere thinning and (ii) reverse post-rift subsidence modelling to give water and Moho depths at breakup time. We show that extensional faulting occurs on steep ( 60°) normal faults in both proximal and distal parts of rifted margins. Extensional faults together with their flexural isostatic response produce not only sub-horizontal exhumed footwall surfaces (i.e. the rolling hinge model) and highly rotated (60 19. Re-assessing Present Day Global Mass Transport and Glacial Isostatic Adjustment From a Data Driven Approach Science.gov (United States) Wu, X.; Jiang, Y.; Simonsen, S.; van den Broeke, M. R.; Ligtenberg, S.; Kuipers Munneke, P.; van der Wal, W.; Vermeersen, B. L. A. 2017-12-01 Determining present-day mass transport (PDMT) is complicated by the fact that most observations contain signals from both present day ice melting and Glacial Isostatic Adjustment (GIA). Despite decades of progress in geodynamic modeling and new observations, significant uncertainties remain in both. The key to separate present-day ice mass change and signals from GIA is to include data of different physical characteristics. We designed an approach to separate PDMT and GIA signatures by estimating them simultaneously using globally distributed interdisciplinary data with distinct physical information and a dynamically constructed a priori GIA model. We conducted a high-resolution global reappraisal of present-day ice mass balance with focus on Earth's polar regions and its contribution to global sea-level rise using a combination of ICESat, GRACE gravity, surface geodetic velocity data, and an ocean bottom pressure model. Adding ice altimetry supplies critically needed dual data types over the interiors of ice covered regions to enhance separation of PDMT and GIA signatures, and achieve half an order of magnitude expected higher accuracies for GIA and consequently ice mass balance estimates. The global data based approach can adequately address issues of PDMT and GIA induced geocenter motion and long-wavelength signatures important for large areas such as Antarctica and global mean sea level. In conjunction with the dense altimetry data, we solved for PDMT coefficients up to degree and order 180 by using a higher-resolution GRACE data set, and a high-resolution a priori PDMT model that includes detailed geographic boundaries. The high-resolution approach solves the problem of multiple resolutions in various data types, greatly reduces aliased errors from a low-degree truncation, and at the same time, enhances separation of signatures from adjacent regions such as Greenland and Canadian Arctic territories. 20. Isostatic gravity map of the Monterey 30 x 60 minute quadrangle and adjacent areas, California Science.gov (United States) Langenheim, V.E.; Stiles, S.R.; Jachens, R.C. 2002-01-01 The digital dataset consists of one file (monterey_100k.iso) containing 2,385 gravity stations. The file, monterey_100k.iso, contains the principal facts of the gravity stations, with one point coded per line. The format of the data is described below. Each gravity station has a station name, location (latitude and longitude, NAD27 projection), elevation, and an observed gravity reading. The data are on the IGSN71 datum and the reference ellipsoid is the Geodetic Reference System 1967 (GRS67). The free-air gravity anomalies were calculated using standard formulas (Telford and others, 1976). The Bouguer, curvature, and terrain corrections were applied to the free-air anomaly at each station to determine the complete Bouguer gravity anomalies at a reduction density of 2.67 g/cc. An isostatic correction was then applied to remove the long-wavelength effect of deep crustal and/or upper mantle masses that isostatically support regional topography. 1. Influence of hot rolling and high speed hydrostatic extrusion on the microstructure and mechanical properties of an ODS RAF steel Energy Technology Data Exchange (ETDEWEB) Oksiuta, Z., E-mail: [email protected] [Bialystok Technical University, Faculty of Mechanical Engineering, Wiejska 45c, 15-352 Bialystok (Poland); Lewandowska, M.; Kurzydlowski, K.J. [Warsaw University of Technology, Faculty of Materials Science and Engineering, Woloska 141, 02-504 Warsaw (Poland); Baluc, N. [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association Euratom-Confederation Suisse, 5232 Villigen PSI (Switzerland) 2011-02-15 An argon gas atomized, pre-alloyed Fe-14Cr-2W-0.3Ti (wt.%) reduced activation ferritic (RAF) steel powder was mechanically alloyed with 0.3wt.% Y{sub 2}O{sub 3} nano-particles in an attritor ball mill and consolidated by hot isostatic pressing at 1150 {sup o}C under a pressure of 200 MPa for 3 h. In the aim to improve its mechanical properties the ODS steel was then submitted to a thermo-mechanical treatment (TMT): hot rolling (HR) at 850 deg. C or high speed hydrostatic extrusion (HSHE) at 900 deg. C, followed by heat treatment (HT). Transmission electron microscopy (TEM) observations of the ODS alloys after TMT and heat treatment revealed the presence of elongated grains in the longitudinal direction, with an average width of 8 {mu}m and an average length of 75 {mu}m, and equiaxed grains, a few microns in diameter, in the transverse direction. Two populations of oxide particles were observed by TEM: large Ti-Al-O particles, up to 250 nm in diameter, usually located at the grain boundaries and small Y-Ti-O nanoclusters, about 2.5 nm in diameter, uniformly distributed in the matrix. Charpy impact tests revealed that the HSHE material exhibits a larger upper shelf energy (5.8 J) than the HR material (2.9 J). The ductile-to-brittle transition temperature of both alloys is relatively high, in the range of 55-72 deg. C. Tensile mechanical properties of both ODS alloys were found satisfactory over the full range of investigated temperatures (23-750 deg. C). The HSHE material exhibits better tensile strength and ductility than the HR material. These results indicate that HSHE can be considered as a promising TMT method for improving the mechanical properties of ODS RAF steels. 2. Pre-Brazed Casting and Hot Radial Pressing: A Reliable Process for the Manufacturing of CFC and W Monoblock Mockups International Nuclear Information System (INIS) Visca, E.; Libera, S.; Mancini, A.; Mazzone, G.; Pizzuto, A.; Testani, C. 2006-01-01 ENEA association is involved in the European International Thermonuclear Experimental Reactor (ITER) R-and-D activities and in particular for the manufacturing of high heat flux plasma-facing components (HHFC), such as the divertor targets, the baffles and the limiters: During the last years ENEA has manufactured actively cooled mock-ups by using different technologies, namely brazing, diffusion bonding and hot isostatic pressing (HIPping). A new manufacturing process has been set up and tested. It was successfully applied for the manufacturing of W armoured monoblock mockups. This technique is the HRP (Hot Radial Pressing) based on performing a radial diffusion bonding between the cooling tube and the armour tile by pressurizing only the internal tube and by keeping the joining zone in vacuum and at the required bonding temperature. The heating is obtained by a standard air furnace. The next step was to apply the HRP technique for the manufacturing of CFC armoured monoblock components. For this purpose some issues have to be solved like as the low CFC tensile strength, the pure copper interlayer between the heat sink and the armour necessary to mitigate the stress at the joint interface and the low wettability of the pure copper on the CFC matrix. This paper reports the research path followed to manufacture a medium scale vertical target CFC and W armoured mockup by HRP. An ad hoc rig able to maintain the CFC in a compressive constant condition was also designed and tested. The casting of a soft copper interlayer between the tube and the tile was performed by a new technique: the Pre-Brazed Casting (PBC, ENEA patent). Some mock-ups with three NB31 CFC tiles were successfully manufactured and tested to thermal fatigue using electron beam facilities. They all reached at least 1000 cycles at 20 MW/m 2 without suffering any damage. The manufactured medium scale vertical target mock-up is now under testing at the FE2000 (France) facility. (author) 3. Solar 'hot spots' are still hot Science.gov (United States) Bai, Taeil 1990-01-01 Longitude distributions of solar flares are not random but show evidence for active zones (or hot spots) where flares are concentrated. According to a previous study, two hot spots in the northern hemisphere, which rotate with a synodic period of about 26.72 days, produced the majority of major flares, during solar cycles 20 and 21. The more prominent of these two hot spots is found to be still active during the rising part of cycle 22, producing the majority of northern hemisphere major flares. The synodic rotation period of this hot spot is 26.727 + or - 0.007 days. There is also evidence for hot spots in the southern hemisphere. Two hot spots separated by 180 deg are found to rotate with a period of 29.407 days, with one of them having persisted in the same locations during cycles 19-22 and the other, during cycles 20-22. 4. Solar hot spots are still hot International Nuclear Information System (INIS) Bai, T. 1990-01-01 Longitude distributions of solar flares are not random but show evidence for active zones (or hot spots) where flares are concentrated. According to a previous study, two hot spots in the northern hemisphere, which rotate with a synodic period of about 26.72 days, produced the majority of major flares, during solar cycles 20 and 21. The more prominent of these two hot spots is found to be still active during the rising part of cycle 22, producing the majority of northern hemisphere major flares. The synodic rotation period of this hot spot is 26.727 + or - 0.007 days. There is also evidence for hot spots in the southern hemisphere. Two hot spots separated by 180 deg are found to rotate with a period of 29.407 days, with one of them having persisted in the same locations during cycles 19-22 and the other, during cycles 20-22. 14 refs 5. Influence of hot rolling and high speed hydrostatic extrusion on the microstructure and mechanical properties of RAF ODS steel International Nuclear Information System (INIS) Oksiuta, Z.; Kurzydlowski, K.J.; Baluc, N. 2009-01-01 Argon gas atomized, pre-alloyed Fe-14Cr-2W-0.3Ti oxide dispersion strengthened (ODS) ferritic steel powder was mechanically alloyed with 0.3Y2O3 (wt.%) nano-particles in attritor ball mill and consolidated by hot isostatic pressing (HIP) at 1150 deg. C under pressure of 200 MPa for 3 hrs. To improve mechanical properties of as HIPped ODS ingots the material was undergone further thermo-mechanical treatment (TMT), namely: hot rolling (HR) at 850 deg. C or high speed hot extrusion (HSHE) at 850 deg. C. After TMT both materials were annealed at 1050 deg. C for 1 h in vacuum. Transmission electron microscopy (TEM) observations of the ODS alloys after TMT and heat treatment exhibited elongated in a longitudinal direction grains with an average size of 75 μm. However, an equiaxed, smaller than 500 nm grains were also found in the microstructure of both materials. Different size and morphology of oxides particles were also observed. Bigger, about 150 nm Ti-Al-O particles were usually located at grain boundaries whereas Y-Ti-O nanoclusters of about 5 nm were uniformly distributed in ODS steel matrix. The Charpy impact tests revealed significantly better about 90% (5.8 J) upper shelf energy (USE) of material after HSHE but ductile to brittle transition temperature (DBTT) of both alloys was unsatisfactory. As-HR ODS steel has shown DBTT of about 55 deg. C whereas HSHE ODS steel has about 75 deg. C. This relatively high values of transition temperature were probably caused by oxides particles present at grain boundaries of the ODS alloys which decreased fracture properties of the ODS steels. High temperature tensile properties of both ODS alloys are found to be satisfactory in full range of the testing temperature from 23 up to 750 deg. C. However, about 15% better UTS and YS0.2 (1350 MPa and 1285 MPa, respectively) as well as ductility were measured in the case of the as-HSHE ODS steel. These results indicates that HSHE process of the ODS steel can be considered as more 6. Spatio-spectral localization of isostatic coherence anisotropy in Australia and its relation to seismic anisotropy : Implications for lithopsheric deformation NARCIS (Netherlands) Simons, Frederik J.; Hilst, R.D. van der; Zuber, M.T. 2003-01-01 We investigate the two-dimensional (2-D) nature of the coherence between Bouguer gravity anomalies and topography on the Australian continent. The coherence function or isostatic response is commonly assumed to be isotropic. However, the fossilized strain field recorded by gravity anomalies and 7. EFFECT OF DIFFERENT COMPACTION PRESSURE AND DIFFERENT SINTERING ROUTE ON K0.5NA0.5NBO₃ PHYSICAL AND DIELECTRIC PROPERTIES Directory of Open Access Journals (Sweden) Nor Fatin Khairah Bahanurddin 2016-07-01 Full Text Available Alkaline niobate known as K0.5Na0.5NbO3 (KNN, a lead-free piezoelectric ceramic was synthesized via a solid state reaction method. The samples were compacted at different pressures (100, 200, 300 and 400 MPa and sintered using two different techniques (conventional furnace and hot isostatic pressing (HIP. The effect of compaction pressure and sintering technique on physical and dielectric properties was studied. The optimum compaction pressure (300 MPa and sintering via HIP (at 1080 °C for 30 min increased the density and grain size ( range 30 - 300 nm and improved its dielectric properties. Therefore, the combination of suitable compaction pressure and sintering technique has produced larger grain size and higher density of KNN which resulted in outstanding dielectric properties. At room temperature, excellent values of ε r (5517.35 and tan δ (0.954, recorded at 1 MHz were measured for the KNN300HIP sample with highest density (4.4885 g/cm³. 8. MIS 5e relative sea-level changes in the Mediterranean Sea: Contribution of isostatic disequilibrium Science.gov (United States) Stocchi, Paolo; Vacchi, Matteo; Lorscheid, Thomas; de Boer, Bas; Simms, Alexander R.; van de Wal, Roderik S. W.; Vermeersen, Bert L. A.; Pappalardo, Marta; Rovere, Alessio 2018-04-01 Sea-level indicators dated to the Last Interglacial, or Marine Isotope Stage (MIS) 5e, have a twofold value. First, they can be used to constrain the melting of Greenland and Antarctic Ice Sheets in response to global warming scenarios. Second, they can be used to calculate the vertical crustal rates at active margins. For both applications, the contribution of glacio- and hydro-isostatic adjustment (GIA) to vertical displacement of sea-level indicators must be calculated. In this paper, we re-assess MIS 5e sea-level indicators at 11 Mediterranean sites that have been generally considered tectonically stable or affected by mild tectonics. These are found within a range of elevations of 2-10 m above modern mean sea level. Four sites are characterized by two separate sea-level stands, which suggest a two-step sea-level highstand during MIS 5e. Comparing field data with numerical modeling we show that (i) GIA is an important contributor to the spatial and temporal variability of the sea-level highstand during MIS 5e, (ii) the isostatic imbalance from the melting of the MIS 6 ice sheet can produce a >2.0 m sea-level highstand, and (iii) a two-step melting phase for the Greenland and Antarctic Ice Sheets reduces the differences between observations and predictions. Our results show that assumptions of tectonic stability on the basis of the MIS 5e records carry intrinsically large uncertainties, stemming either from uncertainties in field data and GIA models. The latter are propagated to either Holocene or Pleistocene sea-level reconstructions if tectonic rates are considered linear through time. 9. Interaction between climate, volcanism, and isostatic rebound in Southeast Alaska during the last deglaciation Science.gov (United States) Praetorius, Summer; Mix, Alan; Jensen, Britta; Froese, Duane; Milne, Glenn A.; Wolhowe, Matthew; Addison, Jason A.; Prahl, Fred 2016-01-01 Observations of enhanced volcanic frequency during the last deglaciation have led to the hypothesis that ice unloading in glaciated volcanic terrains can promote volcanism through decompression melting in the shallow mantle or a reduction in crustal magma storage time. However, a direct link between regional climate change, isostatic adjustment, and the initiation of volcanism remains to be demonstrated due to the difficulty of obtaining high-resolution well-dated records that capture short-term climate and volcanic variability traced to a particular source region. Here we present an exceptionally resolved record of 19 tephra layers paired with foraminiferal oxygen isotopes and alkenone paleotemperatures from marine sediment cores along the Southeast Alaska margin spanning the last deglacial transition. Major element compositions of the tephras indicate a predominant source from the nearby Mt. Edgecumbe Volcanic Field (MEVF). We constrain the timing of this regional eruptive sequence to 14.6–13.1 ka. The sudden increase in volcanic activity from the MEVF coincides with the onset of Bølling–Allerød interstadial warmth, the disappearance of ice-rafted detritus, and rapid vertical land motion associated with modeled regional isostatic rebound in response to glacier retreat. These data support the hypothesis that regional deglaciation can rapidly trigger volcanic activity. Rapid sea surface temperature fluctuations and an increase in local salinity (i.e., δ18Osw) variability are associated with the interval of intense volcanic activity, consistent with a two-way interaction between climate and volcanism in which rapid volcanic response to ice unloading may in turn enhance short-term melting of the glaciers, plausibly via albedo effects on glacier ablation zones. 10. Processing of surrogate nuclear fuel pellets for better dimensional control with dry bag isostatic pressing Energy Technology Data Exchange (ETDEWEB) Hoggan, Rita E., E-mail: [email protected]; Zuck, Larry D., E-mail: [email protected]; Cannon, W. Roger, E-mail: [email protected]; Lessing, Paul A., E-mail: [email protected] 2016-12-15 A study of improved methods of processing fuel pellets was undertaken using ceria and zirconia/yttria/alumina as surrogates. Through proper granulation, elimination of fines and vertical vibration (tapping) of the parts bag prior to dry bag isostatic pressing (DBIP), reproducibility of diameter profiles among multiple pellets of ceria was improved by almost an order of magnitude. Reproducibility of sintered pellets in these studies was sufficient to allow pellets to be introduced into the cladding with a gap between the pellet and cladding on the order of 50 μm to 100 μm but not a uniform gap with tolerance of ±12 μm as is currently required. Deviation from the mean diameter along the length of multiple pellets, and deviation from roundness, decreased after sintering. This is not generally observed with dry pressed pellets. Sintered shrinkage was uniform to ±0.05% and thus, as an alternative, pellets may be machined to tolerance before sintering, thus avoiding the waste associated with post-sinter grinding. - Highlights: • Three methods of granule preparation for two different powder sources were outlined and compared using tap density curves. • A dry bag isostatic press was used to fabricate pellets and longer rods. Thus longer pellets could be fabricated by this technique. • Vertical vibrations to pack granules decreased variation in dimensions from pellet to pellet by a factor of nine. • Sintering shrinkage varied by only 0.1% along the length of a rod. Thus green machining prior to sintering could result in tight tolerances. 11. An Ensemble Analysis of Antarctic Glacial Isostatic Adjustment and Sea Level Science.gov (United States) Lecavalier, B.; Tarasov, L. 2016-12-01 Inferences of past ice sheet evolution that lack any uncertainty assessment (implicit or explicit), have little value. A developing technique for explicit uncertainty quantification of glacial systems is Bayesian calibration of models against large observational data-sets (Tarasov et al., 2012). The foundation for a Bayesian calibration of a 3D glacial systems model (GSM) for Antarctica has recently been completed (Briggs et al., 2013; 2014; Briggs and Tarasov, 2013). Bayesian calibration thoroughly samples model uncertainties against fits to observational data to generate a probability distribution for the Antarctic Ice Sheet deglaciation with explicit and well-defined confidence intervals. To have validity as a complete inference of past ice sheet evolution, Bayesian calibration requires a model that "brackets reality".Past work has shown the GSM to have likely inadequate range of grounding line migration in certain sectors as well as persistent ice thickness biases in topographically complex regions (Briggs et al., 2014). To advance towards full calibration, these deficiencies are being addressed through a number of model developments. The grounding line scheme has been revised (Pollard and DeConto, 2012), the horizontal resolution is increased to 20 km, and boundary conditions are updated. The basal drag representation now includes the sub-grid treatment of the thermo-mechanical impacts of high basal roughness. Parametric uncertainties in basal drag for regions that are presently marine have been re-evaluated. The impact of past changes in ocean temperature on sub ice shelf melt is explicitly incorporated in the current ocean forcing parametric scheme. Uncertainties in earth rheology are also probed to robustly quantify uncertainties affiliated with glacial isostatic adjustment. The ensemble analysis of the Antarctic glacial system provides dynamical bounds on past and present Antarctica glacial isostatic adjustment and sea level contributions. This research 12. Hot tub folliculitis Science.gov (United States) ... survives in hot tubs, especially tubs made of wood. Symptoms The first symptom of hot tub folliculitis ... may help prevent the problem. Images Hair follicle anatomy References D'Agata E. Pseudomonas aeruginosa and other ... 13. Basic investigation on promotion of joint implementation in fiscal 2000. Investigations on development of technology to utilize heat of deep earth pressure type hot water in Hungary; 2000 nendo kyodo jisshi nado suishin kiso chosa hokokusho. Hungary koku shinso chiatsugata onsui no netsuriyo gijutsu kaihatsu chosa Energy Technology Data Exchange (ETDEWEB) NONE 2001-03-01 Investigations and discussions were given on a project to implement district heating, greenhouse heating, and binary power generation by utilizing geothermal resources in Hungary. Hungary has deep earth pressure type hot water areas distributed, that flow hot water of about 90 to 180 degrees C by the bed pressure. The areas that can utilize the hot water were extracted and investigated by using literatures and data. The project plans district heating of about 15,000 households using the geothermal water, heating of greenhouses equivalent to 100,000 m{sup 2}, gas engine power generation by using the flowing fluid pressure and combustion of the generated methane gas, and binary power generation by using the geothermal water. As a result of the discussions, it was revealed that the energy saving effect would save 5,008 Ktoe in 20 years as converted to crude oil, and the greenhouse effect gas reducing effect would reduce 14.2 million t-CO2 in 20 years. The total project cost would be about 16.62 billion yen. The internal profit rate of this project is 11.34%, largely exceeding the opportunity cost, and indicating the financial effect possibility. (NEDO) 14. Isostatic and Decompensative Gravity Anomalies of the Arabian Plate and Surrounding Regions: a Key for the Crustal Structure Science.gov (United States) Kaban, M. K.; El Khrepy, S.; Al-Arifi, N. S. 2016-12-01 The isostatic anomalies are often considered as one of the most useful correction of the gravity field for investigation of the upper crust structure in many practical applications. By applying this correction, a substantial part of the effect of deep density heterogeneity, which dominates in the Bouguer gravity anomaly, can be removed. With this approach, it is not even necessary to know the deep density structure of the crust and upper mantle in details; it is sufficient to prescribe some type of compensation (regional vs. local) and a compensation depth. However, even when all the parameters are chosen correctly, this reduction of the gravity field does not show the full gravity effect of unknown anomalies in the crust. The last ones should be also compensated to some extent; therefore their impact is substantially reduced by the isostatic compensation. Long ago (Cordell et al., 1991), it was suggested a so-called decompensative correction of the isostatic anomalies, which provides a possibility to separate these effects. However, the decompensative correction is very sensitive to the parameters of the compensation scheme. In the present study we analyse the ways to choose these parameters and extend this approach by assuming a possibility for the regional compensation via elastic deformations of the lithosphere. Based on this technique, we estimate the isostatic and decompensative anomalies for the Arabian plate and surrounding regions. The parameters of the isostatic model are chosen based on previous studies. It was demonstrated that the decompensative correction is very significant at the mid-range wavelengths and may exceed 100 mGal, therefore ignoring this effect would lead to wrong conclusions about the upper crust structure. The total amplitude of the decompensative anomalies reaches ±250 mGal, evidencing for both, large density anomalies of the upper crust (including sediments) and strong isostatic disturbances of the lithosphere. These results improve 15. Modeling deflagration waves out of hot spots Science.gov (United States) Partom, Yehuda 2017-01-01 It is widely accepted that shock initiation and detonation of heterogeneous explosives comes about by a two-step process known as ignition and growth. In the first step a shock sweeping through an explosive cell (control volume) creates hot spots that become ignition sites. In the second step, deflagration waves (or burn waves) propagate out of those hot spots and transform the reactant in the cell into reaction products. The macroscopic (or average) reaction rate of the reactant in the cell depends on the speed of those deflagration waves and on the average distance between neighboring hot spots. Here we simulate the propagation of deflagration waves out of hot spots on the mesoscale in axial symmetry using a 2D hydrocode, to which we add heat conduction and bulk reaction. The propagation speed of the deflagration waves may depend on both pressure and temperature. It depends on pressure for quasistatic loading near ambient temperature, and on temperature at high temperatures resulting from shock loading. From the simulation we obtain deflagration fronts emanating out of the hot spots. For 8 to 13 GPa shocks, the emanating fronts propagate as deflagration waves to consume the explosive between hot spots. For higher shock levels deflagration waves may interact with the sweeping shock to become detonation waves on the mesoscale. From the simulation results we extract average deflagration wave speeds. 16. Pre-brazed casting and hot radial pressing: A reliable process for the manufacturing of CFC and W monoblock mock-ups Energy Technology Data Exchange (ETDEWEB) Visca, Eliseo [Associazione EURATOM-ENEA sulla Fusione, C.R. Frascati, Via E. Fermi, 45, IT-00044 Frascati, RM (Italy)], E-mail: [email protected]; Libera, S.; Mancini, A.; Mazzone, G.; Pizzuto, A. [Associazione EURATOM-ENEA sulla Fusione, C.R. Frascati, Via E. Fermi, 45, IT-00044 Frascati, RM (Italy); Testani, C. [CSM S.p.A., IT-00128 Castel Romano, RM (Italy) 2007-10-15 ENEA is involved in the European International Thermonuclear Experimental Reactor (ITER) R and D activities and, in particular, for the manufacturing of high heat flux plasma-facing components (HHFC), such as the divertor targets, the baffles and the limiters. During last years, ENEA has manufactured actively cooled mock-ups by using different technologies, namely brazing, diffusion bonding and hot isostatic pressing (HIPping). A new manufacturing process has been set up and tested. It was successfully applied for the manufacturing of W armoured monoblock mock-ups. This technique is the HRP (hot radial pressing) based on performing a radial diffusion bonding between the cooling tube and the armour tile by pressurizing only internal tube and by keeping the joining zone in vacuum at the required bonding temperature. The heating is obtained by a standard air furnace. The HRP technique is now used for the manufacturing of CFC armoured monoblock components. For this purpose, some issues have to be faced, like the low CFC tensile strength, the pure copper interlayer between the heat sink and the armour necessary to mitigate the stress at the joint interface, and the low wettability of the pure copper on the CFC matrix. This paper reports the research path followed to manufacture a medium scale vertical target CFC and W armoured mock-up by HRP. A casting of a soft copper interlayer between the tube and the tile was obtained by a new technique: the pre-brazed casting (PBC, ENEA patent). Some preliminary mock-ups with three NB31 CFC tiles were successfully manufactured and tested to thermal fatigue using electron beam facilities. They all reached at least 1000 cycles at 20 MW/m{sup 2} without suffering any damage. The manufactured medium scale vertical target mock-up is now under testing at the FE2000 (France) facility. These activities were performed in the frame of ITER-EFDA contracts. 17. Pre-brazed casting and hot radial pressing: A reliable process for the manufacturing of CFC and W monoblock mock-ups International Nuclear Information System (INIS) Visca, Eliseo; Libera, S.; Mancini, A.; Mazzone, G.; Pizzuto, A.; Testani, C. 2007-01-01 ENEA is involved in the European International Thermonuclear Experimental Reactor (ITER) R and D activities and, in particular, for the manufacturing of high heat flux plasma-facing components (HHFC), such as the divertor targets, the baffles and the limiters. During last years, ENEA has manufactured actively cooled mock-ups by using different technologies, namely brazing, diffusion bonding and hot isostatic pressing (HIPping). A new manufacturing process has been set up and tested. It was successfully applied for the manufacturing of W armoured monoblock mock-ups. This technique is the HRP (hot radial pressing) based on performing a radial diffusion bonding between the cooling tube and the armour tile by pressurizing only internal tube and by keeping the joining zone in vacuum at the required bonding temperature. The heating is obtained by a standard air furnace. The HRP technique is now used for the manufacturing of CFC armoured monoblock components. For this purpose, some issues have to be faced, like the low CFC tensile strength, the pure copper interlayer between the heat sink and the armour necessary to mitigate the stress at the joint interface, and the low wettability of the pure copper on the CFC matrix. This paper reports the research path followed to manufacture a medium scale vertical target CFC and W armoured mock-up by HRP. A casting of a soft copper interlayer between the tube and the tile was obtained by a new technique: the pre-brazed casting (PBC, ENEA patent). Some preliminary mock-ups with three NB31 CFC tiles were successfully manufactured and tested to thermal fatigue using electron beam facilities. They all reached at least 1000 cycles at 20 MW/m 2 without suffering any damage. The manufactured medium scale vertical target mock-up is now under testing at the FE2000 (France) facility. These activities were performed in the frame of ITER-EFDA contracts 18. Radioactive waste immobilization in protective ceramic forms by the HIP method at high pressures International Nuclear Information System (INIS) Sayenko, S.Yu.; Kantsedal, V.P.; Tarasov, R.V.; Starchenko, V.A.; Lyubtsev, R.I. 1993-01-01 Intense research activities have been carried out in recent years at the Kharkov Institute of Physics and Technology (KIPT) to develop the method of hot isostatic pressing (HIP) for immobilizing radioactive (primarily, high-level) wastes. With this method, the radioactive material is immobilized in a matrix under the simultaneous action of high pressures (up to 6,000 atm) and appropriate temperatures. The process has 2 variants: (1) radioactive wastes are treated as powders of oxides resulting from calcination during chemical treatment of spent fuel. In this case the radioactive material enters into the crystalline structure of the immobilized matrix or is distributed in the matrix as a homogeneous mixture; (2) protective barrier layers are pressed on spent fuel rods or their pieces as radioactive wastes, by the HIP method (fuel rod encapsulation in a protective form). Based on numerous results from various studies, the authors suggest that various ceramic compositions should be used as protective materials. Here the authors report two trends of their investigations: (1) development of ecologically clean process equipments for radioactive waste treatment by the HIP method; (2) manufacture of promising protective ceramic compositions and investigation of their physico-mechanical properties 19. Isostatic lines’ study to optimize steel space grid envelope structures for tall buildings according to their solicitations OpenAIRE Señís López, Roger 2013-01-01 Based on the first study completed with wind tunnel tests, the aim of this paper is to define a second methodology for the optimization of steel space grid envelope structures for tall buildings according to their isostatic lines according to their solicitations. It is by means of the comparison NatHaz online database and numerical simulation research of wind flow repercussion in buildings, through Computational Fluid Dynamics (CDF), that we can understand and analyse the grid ... 20. The Influence of Sediment Isostatic Adjustment on Sea Level Change and Land Motion Along the U.S. Gulf Coast Science.gov (United States) Kuchar, Joseph; Milne, Glenn; Wolstencroft, Martin; Love, Ryan; Tarasov, Lev; Hijma, Marc 2018-01-01 Sea level rise presents a hazard for coastal populations, and the Mississippi Delta (MD) is a region particularly at risk due to the high rates of land subsidence. We apply a gravitationally self-consistent model of glacial and sediment isostatic adjustment (SIA) along with a realistic sediment load reconstruction in this region for the first time to determine isostatic contributions to relative sea level (RSL) and land motion. We determine optimal model parameters (Earth rheology and ice history) using a new high-quality compaction-free sea level indicator database. Using the optimal model parameters, we show that SIA can lower predicted RSL in the MD area by several meters over the Holocene and so should be taken into account when modeling these data. We compare modeled contemporary rates of vertical land motion with those inferred using GPS. This comparison indicates that isostatic processes can explain the majority of the observed vertical land motion north of latitude 30.7°N, where subsidence rates average about 1 mm/yr; however, subsidence south of this latitude shows large data-model discrepancies of greater than 3 mm/yr, indicating the importance of nonisostatic processes. This discrepancy extends to contemporary RSL change, where we find that the SIA contribution in the Delta is on the order of 10-1 mm/yr. We provide estimates of the isostatic contributions to 20th and 21st century sea level rates at Gulf Coast Permanent Service for Mean Sea Level tide gauge locations as well as vertical and horizontal land motion at GPS station locations near the MD. 1. Hot wire radicals and reactions International Nuclear Information System (INIS) Zheng Wengang; Gallagher, Alan 2006-01-01 Threshold ionization mass spectroscopy is used to measure radical (and stable gas) densities at the substrate of a tungsten hot wire (HW) reactor. We report measurements of the silane reaction probability on the HW and the probability of Si and H release from the HW. We describe a model for the atomic H release, based on the H 2 dissociation model. We note major variations in silicon-release, with dependence on prior silane exposure. Measured radical densities versus silane pressure yield silicon-silane and H-silane reaction rate coefficients, and the dominant radical fluxes to the substrate 2. ISOSTATICALLY DISTURBED TERRAIN OF NORTHWESTERN ANDES MOUNTAINS FROM SPECTRALLY CORRELATED FREE-AIR AND GRAVITY TERRAIN DATA Directory of Open Access Journals (Sweden) Hernández P Orlando 2006-12-01 Full Text Available Recently revised models on global tectonics describe the convergence of the North Andes, Nazca, Caribbean and South American Plates and their seismicity, volcanism, active faulting and extreme topography. The current plate boundaries of the area are mainly interpreted from volcanic and seismic datasets with variable confidence levels. New insights on the isostatic state and plate boundaries of the northwestern Andes Mountains can be obtained from the spectral analysis of recently available gravity and topography data. Isostatically disturbed terrain produces free-air anomalies that are highly correlated with the gravity effects of the terrain. The terrain gravity effects (TGE and free air gravity anomalies (FAGA of the Andes mountains spectral correlation data confirms that these mountains are isostatically disturbed. Strong negative terrain-correlated FAGA along western South America and the Greater and Lesser Antilles are consistent with anomalously deepened mantle displaced by subducting oceanic plates. Inversion of the compensated terrain gravity effects (CTGE reveals plate subduction systems with alternating shallower and steeper subduction angles. The gravity modeling highlights crustal deformation from plate collision and subduction and other constraints on the tectonism of the plate boundary zones for the region. 3. Hot Surface Ignition OpenAIRE Tursyn, Yerbatyr; Goyal, Vikrant; Benhidjeb-Carayon, Alicia; Simmons, Richard; Meyer, Scott; Gore, Jay P. 2015-01-01 Undesirable hot surface ignition of flammable liquids is one of the hazards in ground and air transportation vehicles, which primarily occurs in the engine compartment. In order to evaluate the safety and sustainability of candidate replacement fuels with respect to hot surface ignition, a baseline low lead fuel (Avgas 100 LL) and four experimental unleaded aviation fuels recommended for reciprocating aviation engines were considered. In addition, hot surface ignition properties of the gas tu... 4. Glacial isostatic adjustment on the Northern Hemisphere - new results from GRACE Science.gov (United States) Mueller, J.; Steffen, H.; Gitlein, O.; Denker, H.; Timmen, L. 2007-12-01 The Earth's gravity field mapped by the Gravity Recovery and Climate Experiment (GRACE) satellite mission shows variations due to the integral effect of mass variations in the atmosphere, hydrosphere and geosphere. The Earth's gravity field is provided in form of monthly solutions by several institutions, e.~g. GFZ Potsdam, CSR and JPL. During the GRACE standard processing of these analysis centers, oceanic and atmospheric contributions as well as tidal effects are reduced. The solutions of the analysis centers differ slightly, which is due the application of different reduction models and center-specific processing schemes. We present our investigation of mass variations in the areas of glacial isostatic adjustment (GIA) in North America and Northern Europe from GRACE data. One key issue is the separation of GIA parts and the reduction of the observed quantities by applying dedicated filters (e.~g. isotropic, non-isotropic, and destriping filters) and global models of hydrological variations (e.~g. WGHM, LaDWorld, GLDAS). In a further step, we analyze the results of both regions regarding their reliability, and finally present a comparison to results of a geodynamical modeling and absolute gravity measurements. Our results clearly show that the quality of the GRACE-derived gravity- change signal benefits from improved reduction models and chosen analysis techniques. Nevertheless, the comparison to results of geodynamic models still reveals differences, and thus further studies are in progress. 5. Gravity measurements in southeastern Alaska reveal negative gravity rate of change caused by glacial isostatic adjustment Science.gov (United States) Sun, W.; Miura, S.; Sato, T.; Sugano, T.; Freymueller, J.; Kaufman, M.; Larsen, C. F.; Cross, R.; Inazu, D. 2010-12-01 For the past 300 years, southeastern Alaska has undergone rapid ice-melting and land uplift attributable to global warming. Corresponding crustal deformation (3 cm/yr) caused by the Little Ice Age retreat is detectable with modern geodetic techniques such as GPS and tidal gauge measurements. Geodetic deformation provides useful information for assessing ice-melting rates, global warming effects, and subcrustal viscosity. Nevertheless, integrated geodetic observations, including gravity measurements, are important. To detect crustal deformation caused by glacial isostatic adjustment and to elucidate the viscosity structure in southeastern Alaska, Japanese and U.S. researchers began a joint 3-year project in 2006 using GPS, Earth tide, and absolute gravity measurements. A new absolute gravity network was established, comprising five sites around Glacier Bay, near Juneau, Alaska. This paper reports the network's gravity measurements during 2006-2008. The bad ocean model in this area hindered ocean loading correction: Large tidal residuals remain in the observations. Accurate tidal correction necessitated on-site tidal observation. Results show high observation precision for all five stations: day ice thickness changes. A gravity bias of about -13.2 ± 0.1 mGal exists between the Potsdam and current FG5 gravity data. 6. Geologic and isostatic map of the Nenana Basin area, central Alaska Science.gov (United States) Frost, G.M.; Barnes, D.F.; Stanley, R.G. 2002-01-01 Introduction The Nenana Basin area is a prospective petroleum province in central Alaska, and this geologic and isostatic gravity map is part of a petroleum resource assessment of the area. The geology was compiled from published sources (Chapman and others, 1971, 1975a, 1975b, 1982; Chapman and Yeend, 1981; Csejtey and others, 1986; Jones and others, 1983; Pewe and others, 1966; Reed, 1961; and Weber and others, 1992), as shown on the index map (map sheet). Map units are organized and presented according to the scheme of lithotectonic terranes proposed by Jones and others (1987) and Silberling and Jones (1984); we recognize, however, that this terrane scheme is controversial and likely to be revised in the future. In some cases, we combined certain terranes because we were unable to match the terrane boundaries given by Jones and others (1987) and Silberling and Jones (1984) with specific faults shown on existing geologic maps. Postaccretion cover deposits represent overlap assemblages that depositionally overlie accreted terranes. Plutonic igneous rocks shown on this map include several plutons that are clearly postaccretionary, based on isotopic ages and (or) field relations. It is possible that some of the plutons predate accretion, but this has not been demonstrated. According to Jones and others (1982), the terranes in the area of our map were assembled during late Mesozoic or earliest Cenozoic time. The gravity contours are derived from data used in earlier compilations (Barnes, 1961, 1977; Hackett, 1981; Valin and others, 1991; Frost and Stanley, 1991) that are supplemented by some National Oceanic and Atmospheric Administration data along the Alaska Pipeline level line (W.E. Strange, written commun., 1980). The earlier compilations were used for simple Bouguer maps, prepared primarily by non-digital methods, and are superseded by this map. The present map is the result of digital processing that includes the 1967 Geodetic Reference System, the IGSN-71 7. Nd:YAG transparent ceramics fabricated by direct cold isostatic pressing and vacuum sintering Science.gov (United States) Ge, Lin; Li, Jiang; Zhou, Zhiwei; Liu, Binglong; Xie, Tengfei; Liu, Jing; Kou, Huamin; Shi, Yun; Pan, Yubai; Guo, Jingkun 2015-12-01 The sintering behavior of neodymium doped yttrium aluminum garnet (Nd:YAG) ceramics was investigated on the basis of densification trajectory, microstructure evolution and transmittance. Nd:YAG ceramics with in-line transmittance of 83.9% at 1064 nm and 82.5% at 400 nm were obtained by direct cold isostatic pressing (CIP) at 250 MPa and solid-state reactive sintering at 1790 °C for 30 h under vacuum. Compared with the porosity and the average pore diameter of the sample from uniaxial dry-pressing followed by CIP, those from direct CIP are much smaller. The samples pressed at 250 MPa were sintered from 1500 °C to 1750 °C for 0.5-20 h to study their sintering behavior. At the temperature higher than 1500 °C, pure YAG phase is formed, followed by the densification and grain growth process. The relative density and the grain size increase with the increase of sintering time and temperature, and the sintering behavior is more sensitive to temperature than holding time. The mechanism controlling densification and grain growth at sintering temperature of 1550 °C is grain boundary diffusion. 8. Preliminary isostatic residual gravity anomaly map of Paso Robles 30 x 60 minute quadrangle, California Science.gov (United States) McPhee, D.K.; Langenheim, V.E.; Watt, J.T. 2011-01-01 This isostatic residual gravity map is part of an effort to map the three-dimensional distribution of rocks in the central California Coast Ranges and will serve as a basis for modeling the shape of basins and for determining the location and geometry of faults within the Paso Robles quadrangle. Local spatial variations in the Earth\\'s gravity field, after accounting for variations caused by elevation, terrain, and deep crustal structure reflect the distribution of densities in the mid- to upper crust. Densities often can be related to rock type, and abrupt spatial changes in density commonly mark lithological or structural boundaries. High-density rocks exposed within the central Coast Ranges include Mesozoic granitic rocks (exposed northwest of Paso Robles), Jurassic to Cretaceous marine strata of the Great Valley Sequence (exposed primarily northeast of the San Andreas fault), and Mesozoic sedimentary and volcanic rocks of the Franciscan Complex [exposed in the Santa Lucia Range and northeast of the San Andreas fault (SAF) near Parkfield, California]. Alluvial sediments and Tertiary sedimentary rocks are characterized by low densities; however, with increasing depth of burial and age, the densities of these rocks may become indistinguishable from those of older basement rocks. 9. Depressurization test on hot gas duct International Nuclear Information System (INIS) Tanihira, Masanori; Kunitomi; Kazuhiko; Inagaki, Yoshiyuki; Miyamoto, Yoshiaki; Sato, Yutaka. 1989-05-01 To study the integrity of internal structures and the characteristics in a hot gas duct under the rapid depressurization accident, depressurization tests have been carried out using a test apparatus installed the hot gas duct with the same size and the same structures as that of the High Temperature Engineering Test Reactor (HTTR). The tests have been performed with three parameters: depressurization rate (0.14-3.08 MPa/s) determined by orifice diameter, area of the open space at the slide joint (11.9-2036 mm 2 ), and initial pressure (1.0-4.0 MPa) filled up in a pressure vessel, by using nitrogen gas and helium gas. The maximum pressure difference applied on the internal structures of the hot gas duct was 2.69 MPa on the liner tube and 0.45 MPa on the separating plate. After all tests were completed, the hot gas duct which was used in the tests was disassembled. Inspection revealed that there were no failure and no deformation on the internal structures such as separating plates, insulation layers, a liner tube and a pressure tube. (author) 10. Processing map and hot working mechanisms in a P/M TiAl alloy composite with in situ carbide and silicide dispersions International Nuclear Information System (INIS) Rao, K.P.; Prasad, Y.V.R.K. 2010-01-01 Research highlights: Mechanical alloying of Ti and Al with small additions of Si and C was used to synthesize metastable phases, which were incorporated in Ti-Al matrices using powder metallurgy techniques. These metastable phases (or also called as precursors), at higher temperatures, transformed in situ into very fine hard reinforcements that develop coherent interface with the surrounding matrix. Typically, Ti5Si3 and TiC are the end products after the synthesis of composite. In this study, hot working behavior of such composites has been studied using the concepts of processing maps to identify the safe and best processing conditions that should be adopted while forming this composite. Also, kinetic analysis of hot deformation has been performed to identify the dominant deformation mechanism. The results are compared with that of base TiAl matrix. The powder metallurgy route offers the advantage of working the material at much lower temperatures compared to the traditional cast and forge route. - Abstract: A titanium aluminide alloy composite with in situ carbide and silicide dispersions has been synthesized by mixing 90% of matrix with elemental composition of 46Ti-46Al-4Nb-2Cr-2Mn and 10% precursor with composition 55Ti-27Al-12Si-6C prepared by mechanical alloying. The powder mixture was blended for 2 h followed by hot isostatic pressing (HIP) at 1150 deg. C for 4 h under a pressure of 150 MPa. In addition to TiAl alloy matrix, the microstructure of the HIP'ed billet showed a small volume fraction of Nb-rich intermetallic phase along with carbide and silicide dispersions formed in situ during HIP'ing. Cylindrical specimens from the HIP'ed billets were compressed at temperatures and strain rates in the ranges of 800-1050 deg. C and 0.0001-1 s -1 . The flow curves exhibited flow softening leading to a steady-state flow at strain rates lower than 0.01 s -1 while fracture occurred at higher strain rates. The processing map developed on the basis of flow stress at 11. World Gravity Map: a set of global complete spherical Bouguer and isostatic anomaly maps and grids Science.gov (United States) Bonvalot, S.; Balmino, G.; Briais, A.; Kuhn, M.; Peyrefitte, A.; Vales, N.; Biancale, R.; Gabalda, G.; Reinquin, F. 2012-04-01 We present here a set of digital maps of the Earth's gravity anomalies (surface free air, Bouguer and isostatic), computed at Bureau Gravimetric International (BGI) as a contribution to the Global Geodetic Observing Systems (GGOS) and to the global geophysical maps published by the Commission for the Geological Map of the World (CGMW) with support of UNESCO and other institutions. The Bouguer anomaly concept is extensively used in geophysical interpretation to investigate the density distributions in the Earth's interior. Complete Bouguer anomalies (including terrain effects) are usually computed at regional scales by integrating the gravity attraction of topography elements over and beyond a given area (under planar or spherical approximations). Here, we developed and applied a worldwide spherical approach aimed to provide a set of homogeneous and high resolution gravity anomaly maps and grids computed at the Earth's surface, taking into account a realistic Earth model and reconciling geophysical and geodetic definitions of gravity anomalies. This first version (1.0) has been computed by spherical harmonics analysis / synthesis of the Earth's topography-bathymetry up to degree 10800. The detailed theory of the spherical harmonics approach is given in Balmino et al., (Journal of Geodesy, 2011). The Bouguer and terrain corrections have thus been computed in spherical geometry at 1'x1' resolution using the ETOPO1 topography/bathymetry, ice surface and bedrock models from the NOAA (National Oceanic and Atmospheric Administration) and taking into account precise characteristics (boundaries and densities) of major lakes, inner seas, polar caps and of land areas below sea level. Isostatic corrections have been computed according to the Airy-Heiskanen model in spherical geometry for a constant depth of compensation of 30km. The gravity information given here is provided by the Earth Geopotential Model (EGM2008), developed at degree 2160 by the National Geospatial 12. Isostatic compaction of beaker shaped bentonite blocks on the scale 1:4 Energy Technology Data Exchange (ETDEWEB) Johannesson, Lars-Erik [Clay Technology AB, Lund (Sweden); Nord, Sven [Ifoe Ceramics AB, Bromoella (Sweden ); Pusch, Roland [Geodevelopment AB, Lund (Sweden); Sjoeblom, Rolf [AaF-Energikonsult AB, Stockholm (Sweden) 2000-09-01 The purpose of the present work is to test, on a scale of 1:4, the feasibility of manufacturing bentonite blocks by isostatic compaction for application as a buffer material in a repository for spent nuclear fuel. In order for the tests to be sensitive to any weaknesses of the method, the blocks were shaped as beakers. The scope included the following: 1. Preparation of powder: a. mixing of the bentonite and addition of water in predetermined amounts, b. sieving to remove any lumps generated; 2. Isostatic compaction: a. establishment of a separate laboratory for the handling of bentonite powder (weighing, mixing, filling, sampling and machining), b. development and design of equipment and procedures for compaction of bentonite to beaker-shaped specimens, c. compaction process operation, d. visual inspection; 3. Sampling and characterisation: a. extraction of samples from the blocks made, b. determination of water content, c. determination of density, d. determination of strain at maximum stress by means of bending tests, e. determination of tensile strength by means of bending tests, f. determination of geometries of the blocks prepared; 4. Post-treatment by means of machining: a. machining of blocks made, b. visual inspection; 5. Evaluation. The work went very smoothly. No significant obstacles or unexpected events were encountered. The conclusions are as follows: The conclusions drawn in this report from work on the (linear)scale of one to four are very relevant to the full scale. Mixing of bentonite powder as well as moistening can be carried out on a pilot scale with a good homogeneity and with maintained good quality of the press powder. The compaction of bentonite can be carried out in a similar manner to the present operation at Ifoe Ceramics AB. This implies a very efficient handling as well as a very efficient use of the time in the press which may account for a large proportion of the total cost. The blocks could readily be produced to reproducible 13. Glacial Isostatic Adjustment as a Source of Noise for the Interpretation of GRACE Data Science.gov (United States) Wahr, J.; Velicogna, I.; Paulson, A. 2009-05-01 Viscoelastic relaxation in the Earth's mantle caused by wide-spread deglaciation following the last glacial maximum (LGM), can appear as a secular trend in measurements of the Earth's time-variable gravity field. The presence of this trend can provide an opportunity to use gravity observations to constrain models of the glacial isostatic adjustment (GIA) process. But it can also be a nuisance for people who are using the gravity observations to learn about other things. Gravity observations, whether from satellites or from ground-based gravimeters, can not distinguish between the gravitational effects of water/snow/ice variations on or near the surface, and those caused by density variations deep within the mantle. Unmodeled or mismodeled GIA signals can sometimes make it difficult to use gravity observations to learn about secular changes in water/snow/ice from such places as northern Canada, Scandinavia, Antarctica, and Greenland: places where there was considerable long-term deglaciation following the LGM. These issues have become particularly important since the 2002 launch of the GRACE gravity satellite mission. GIA signals in northern Canada and Scandinavia are clearly evident in the GRACE data. But the presence of GIA signals in these and other regions has sometimes caused problems for long-term hydrological and, especially, cryospheric studies with GRACE. GIA model errors, for example, are by far the largest source of uncertainty when using GRACE to estimate present-day thinning rates of the Antarctic ice sheet. This talk will discuss the contributions of the GIA signal to GRACE time-variable gravity measurements; partly as an opportunity to study the GIA process, but mostly as a source of uncertainty for other applications. 14. Empirical estimation of present-day Antarctic glacial isostatic adjustment and ice mass change Science.gov (United States) Gunter, B. C.; Didova, O.; Riva, R. E. M.; Ligtenberg, S. R. M.; Lenaerts, J. T. M.; King, M. A.; van den Broeke, M. R.; Urban, T. 2014-04-01 This study explores an approach that simultaneously estimates Antarctic mass balance and glacial isostatic adjustment (GIA) through the combination of satellite gravity and altimetry data sets. The results improve upon previous efforts by incorporating a firn densification model to account for firn compaction and surface processes as well as reprocessed data sets over a slightly longer period of time. A range of different Gravity Recovery and Climate Experiment (GRACE) gravity models were evaluated and a new Ice, Cloud, and Land Elevation Satellite (ICESat) surface height trend map computed using an overlapping footprint approach. When the GIA models created from the combination approach were compared to in situ GPS ground station displacements, the vertical rates estimated showed consistently better agreement than recent conventional GIA models. The new empirically derived GIA rates suggest the presence of strong uplift in the Amundsen Sea sector in West Antarctica (WA) and the Philippi/Denman sectors, as well as subsidence in large parts of East Antarctica (EA). The total GIA-related mass change estimates for the entire Antarctic ice sheet ranged from 53 to 103 Gt yr-1, depending on the GRACE solution used, with an estimated uncertainty of ±40 Gt yr-1. Over the time frame February 2003-October 2009, the corresponding ice mass change showed an average value of -100 ± 44 Gt yr-1 (EA: 5 ± 38, WA: -105 ± 22), consistent with other recent estimates in the literature, with regional mass loss mostly concentrated in WA. The refined approach presented in this study shows the contribution that such data combinations can make towards improving estimates of present-day GIA and ice mass change, particularly with respect to determining more reliable uncertainties. 15. Ice loading model for Glacial Isostatic Adjustment in the Barents Sea constrained by GRACE gravity observations Science.gov (United States) Root, Bart; Tarasov, Lev; van der Wal, Wouter 2014-05-01 The global ice budget is still under discussion because the observed 120-130 m eustatic sea level equivalent since the Last Glacial Maximum (LGM) can not be explained by the current knowledge of land-ice melt after the LGM. One possible location for the missing ice is the Barents Sea Region, which was completely covered with ice during the LGM. This is deduced from relative sea level observations on Svalbard, Novaya Zemlya and the North coast of Scandinavia. However, there are no observations in the middle of the Barents Sea that capture the post-glacial uplift. With increased precision and longer time series of monthly gravity observations of the GRACE satellite mission it is possible to constrain Glacial Isostatic Adjustment in the center of the Barents Sea. This study investigates the extra constraint provided by GRACE data for modeling the past ice geometry in the Barents Sea. We use CSR release 5 data from February 2003 to July 2013. The GRACE data is corrected for the past 10 years of secular decline of glacier ice on Svalbard, Novaya Zemlya and Frans Joseph Land. With numerical GIA models for a radially symmetric Earth, we model the expected gravity changes and compare these with the GRACE observations after smoothing with a 250 km Gaussian filter. The comparisons show that for the viscosity profile VM5a, ICE-5G has too strong a gravity signal compared to GRACE. The regional calibrated ice sheet model (GLAC) of Tarasov appears to fit the amplitude of the GRACE signal. However, the GRACE data are very sensitive to the ice-melt correction, especially for Novaya Zemlya. Furthermore, the ice mass should be more concentrated to the middle of the Barents Sea. Alternative viscosity models confirm these conclusions. 16. Using coastal lagoons to better constrain the isostatic signal in the western Mediterranean Sea Science.gov (United States) Vacchi, M.; Rovere, A.; Melis, R. T.; Ghilardi, M.; Marriner, N.; Giaime, M. 2017-12-01 Coastal lagoons represent a very common feature of the microtidal Mediterranean coastlines. They are inland waterbodies, usually developing parallel to the coast, typically separated from the open sea by a sandy barrier. One or more restricted inlets ensure their continuous or intermittent connection to the open sea. The water depth is generally less than 1 m and seldom exceeds a few meters. They represent a very useful proxy for the reconstruction of Mediterranean Relative Sea Level (RSL). However, caution should be used in the definition of a correct indicative meaning that can be obtained only with a multiproxy analysis of both sedimentary features and faunal assemblages of the cores extracted in marshy to lagoonal environment. We report here the results of a wide coring campaign we carried out in in the last 2 years in a number of Mediterranean lagoons located close to important archaeological settlements in Corsica (France) Sardinia (Italy) and Mallorca Island (Spain). The multiproxy analysis of the cores allowed defining the depositional environments and their relationship (or non relationship) with the former mean sea level. These data were chronologically supported by a significant dataset of more than 100 new 14C dating performed on organic sediments, wood, plant remains and marine/lagoonal shells. We then produced alarge amount of new data to constrain the RSL evolution in the center of Western Mediterranean where the available geophysical models predict the largest glacio-hydro isostatic (GIA) influence at basin scale. However, such models where tested only on a limited dataset mainly composed of archaeological RSL indicators (i.e. last 2 ka BP). Our new record, expanding the last 10 ka BP, significantly improves the ability to define the general anatomy of Mediterranean Holocene RSL changes and to constrain the maximal GIA magnitude in the basin. 17. Control apparatus for hot gas engine Science.gov (United States) Stotts, Robert E. 1986-01-01 A mean pressure power control system for a hot gas (Stirling) engine utilizing a plurality of supply tanks for storing a working gas at different pressures. During pump down operations gas is bled from the engine by a compressor having a plurality of independent pumping volumes. In one embodiment of the invention, a bypass control valve system allows one or more of the compressor volumes to be connected to the storage tanks. By selectively sequencing the bypass valves, a capacity range can be developed over the compressor that allows for lower engine idle pressures and more rapid pump down rates. 18. Hot pressing of B4C/SiC composites International Nuclear Information System (INIS) Sahin, F.C.; Turhan, E.; Yesilcubuk, S.A.; Addemir, O. 2005-01-01 B 4 C/SiC ceramic composites containing 10-20-30 vol % SiC were prepared by hot pressing method. The effect of SiC addition and hot pressing temperature on sintering behaviour and mechanical properties of hot pressed composites were investigated. Microstructures of hot pressed samples were examined by SEM technique. Three different temperatures (2100 deg. C, 2200 deg. C and 2250 deg. C) were used to optimize hot pressing temperature applying 100 MPa pressure under argon atmosphere during the sintering procedure. The highest relative density of 98.44 % was obtained by hot pressing at 2250 deg. C. However, bending strengths of B 4 C/SiC composite samples were lower than monolithic B 4 C in all experimental conditions. (authors) 19. Development of equipment for in situ studies of biofilm in hot water systems DEFF Research Database (Denmark) Bagh, Lene Karen; Albrechtsen, Hans-Jørgen; Arvin, Erik 1999-01-01 New equipment was developed for in situ studies of biofilms in hot water tanks and hot water pipes under normal operation and pressure. Sampling ports were installed in the wall of a hot water tank and through these operating shafts were inserted with a test plug in the end. The surface of the test... 20. MIS hot electron devices for enhancement of surface reactivity by hot electrons DEFF Research Database (Denmark) Thomsen, Lasse Bjørchmar A Metal-Insulator-Semiconductor (MIS) based device is developed for investigation of hot electron enhanced chemistry. A model of the device is presented explaining the key concepts of the functionality and the character- istics. The MIS hot electron emitter is fabricated using cleanroom technology...... and the process sequence is described. An Ultra High Vacuum (UHV) setup is modified to facilitate experiments with electron emission from the MIS hot electron emitters and hot electron chemistry. Simulations show the importance of keeping tunnel barrier roughness to an absolute minimum. The tunnel oxide...... to be an important energy loss center for the electrons tunneling through the oxide lowering the emission e±ciency of a factor of 10 for a 1 nm Ti layer thickness. Electron emission is observed under ambient pressure conditions and in up to 2 bars of Ar. 2 bar Ar decrease the emission current by an order... 1. Power control system for a hot gas engine Science.gov (United States) Berntell, John O. 1986-01-01 A power control system for a hot gas engine of the type in which the power output is controlled by varying the mean pressure of the working gas charge in the engine has according to the present invention been provided with two working gas reservoirs at substantially different pressure levels. At working gas pressures below the lower of said levels the high pressure gas reservoir is cut out from the control system, and at higher pressures the low pressure gas reservoir is cut out from the system, thereby enabling a single one-stage compressor to handle gas within a wide pressure range at a low compression ratio. 2. Hot Weather Tips Science.gov (United States) ... the person plenty of water and fruit or vegetable juice even if they say they’re not thirsty. No alcohol, coffee or tea. Seek medical help if you suspect dehydration. Light meals: Avoid hot, heavy meals and don’ ... 3. China's 'Hot Money' Problems National Research Council Canada - National Science Library Martin, Michael F; Morrison, Wayne M 2008-01-01 .... The recent large inflow of financial capital into China, commonly referred to as "hot money," has led some economists to warn that such flows may have a destabilizing effect on China's economy... 4. Introduction of hot cell facility in research center Rez - Poster International Nuclear Information System (INIS) Petrickova, A.; Srba, O.; Miklos, M.; Svoboda, P. 2015-01-01 This poster presents the hot cell facility which is being constructed as part of the SUSEN project at the Rez research center (Czech Republic). Within this project a new complex of 10 hot cells and one semi-hot cell will be built. There will be 8 gamma hot cells and 2 alpha hot cells. In each hot cell a hermetic, removable box made of stainless steel will home different type of devices. The hot cells and semi hot cell will be equipped with devices for processing samples (cutting, welding, drilling, machining) as well as equipment for testing (sample preparation area, stress testing machine, fatigue machine, electromechanical creep machine, high frequency resonance pulsator...) and equipment for studying material microstructure (nano-indenter with nano-scratch tester and scanning electron microscope). An autoclave with water loop, installed in a cell will allow mechanical testing in control environment of water, pressure and temperature. A scheme shows the equipment of each cell. This hot laboratory will be able to cover all the process to study radioactive materials: receiving the material, the preparation of the samples, mechanical testing and microstructure observation. Our hot cells will be close to the research nuclear reactor LVR-15 and new irradiation facility (high irradiation by cobalt source) is planned to be built within the SUSEN project 5. The impact of lateral variations in lithospheric thickness on glacial isostatic adjustment in West Antarctica Science.gov (United States) Nield, Grace A.; Whitehouse, Pippa L.; van der Wal, Wouter; Blank, Bas; O'Donnell, John Paul; Stuart, Graham W. 2018-04-01 Differences in predictions of Glacial Isostatic Adjustment (GIA) for Antarctica persist due to uncertainties in deglacial history and Earth rheology. The Earth models adopted in many GIA studies are defined by parameters that vary in the radial direction only and represent a global average Earth structure (referred to as 1D Earth models). Over-simplifying actual Earth structure leads to bias in model predictions in regions where Earth parameters differ significantly from the global average, such as West Antarctica. We investigate the impact of lateral variations in lithospheric thickness on GIA in Antarctica by carrying out two experiments that use different rheological approaches to define 3D Earth models that include spatial variations in lithospheric thickness. The first experiment defines an elastic lithosphere with spatial variations in thickness inferred from seismic studies. We compare the results from this 3D model with results derived from a 1D Earth model that has a uniform lithospheric thickness defined as the average of the 3D lithospheric thickness. Irrespective of deglacial history and sub-lithospheric mantle viscosity, we find higher gradients of present-day uplift rates (i.e. higher amplitude and shorter wavelength) in West Antarctica when using the 3D models, due to the thinner-than-1D-average lithosphere prevalent in this region. The second experiment uses seismically-inferred temperature as input to a power-law rheology thereby allowing the lithosphere to have a viscosity structure. Modelling the lithosphere with a power-law rheology results in behaviour that is equivalent to a thinner-lithosphere model, and it leads to higher amplitude and shorter wavelength deformation compared with the first experiment. We conclude that neglecting spatial variations in lithospheric thickness in GIA models will result in predictions of peak uplift and subsidence that are biased low in West Antarctica. This has important implications for ice-sheet modelling 6. Evaluating Greenland glacial isostatic adjustment corrections using GRACE, altimetry and surface mass balance data International Nuclear Information System (INIS) Sutterley, Tyler C; Velicogna, Isabella; Csatho, Beata; Rezvan-Behbahani, Soroush; Babonis, Greg; Van den Broeke, Michiel 2014-01-01 Glacial isostatic adjustment (GIA) represents a source of uncertainty for ice sheet mass balance estimates from the Gravity Recovery and Climate Experiment (GRACE) time-variable gravity measurements. We evaluate Greenland GIA corrections from Simpson et al (2009 Quat. Sci. Rev. 28 1631–57), A et al (2013 Geophys. J. Int. 192 557–72) and Wu et al (2010 Nature Geosci. 3 642–6) by comparing the spatial patterns of GRACE-derived ice mass trends calculated using the three corrections with volume changes from ICESat (Ice, Cloud, and land Elevation Satellite) and OIB (Operation IceBridge) altimetry missions, and surface mass balance products from the Regional Atmospheric Climate Model (RACMO). During the period September 2003–August 2011, GRACE ice mass changes obtained using the Simpson et al (2009 Quat. Sci. Rev. 28 1631–57) and A et al (2013 Geophys. J. Int. 192 557–72) GIA corrections yield similar spatial patterns and amplitudes, and are consistent with altimetry observations and surface mass balance data. The two GRACE estimates agree within 2% on average over the entire ice sheet, and better than 15% in four subdivisions of Greenland. The third GRACE estimate corrected using the (Wu et al 2010 Nature Geosci. 3 642–6)) GIA shows similar spatial patterns, but produces an average ice mass loss for the entire ice sheet that is 64 − 67 Gt yr −1 smaller. In the Northeast the recovered ice mass change is 46–49 Gt yr −1 (245–270%) more positive than that deduced from the other two corrections. By comparing the spatial and temporal variability of the GRACE estimates with trends of volume changes from altimetry and surface mass balance from RACMO, we show that the Wu et al (2010 Nature Geosci. 3 642–6) correction leads to a large mass increase in the Northeast that is inconsistent with independent observations. (paper) 7. Radial and tangential gravity rates from GRACE in areas of glacial isostatic adjustment Science.gov (United States) van der Wal, Wouter; Kurtenbach, Enrico; Kusche, Jürgen; Vermeersen, Bert 2011-11-01 In areas dominated by Glacial Isostatic Adjustment (GIA), the free-air gravity anomaly rate can be converted to uplift rate to good approximation by using a simple spectral relation. We provide quantitative comparisons between gravity rates derived from monthly gravity field solutions (GFZ Potsdam, CSR Texas, IGG Bonn) from the Gravity Recovery and Climate Experiment (GRACE) satellite mission with uplift rates measured by GPS in these areas. The band-limited gravity data from the GRACE satellite mission can be brought to very good agreement with the point data from GPS by using scaling factors derived from a GIA model (the root-mean-square of differences is 0.55 mm yr-1 for a maximum uplift rate signal of 10 mm yr-1). The root-mean-square of the differences between GRACE derived uplift rates and GPS derived uplift rates decreases with increasing GRACE time period to a level below the uncertainty that is expected from GRACE observations, GPS measurements and the conversion from gravity rate to uplift rate. With the current length of time-series (more than 8 yr) applying filters and a hydrology correction to the GRACE data does not reduce the root-mean-square of differences significantly. The smallest root-mean-square was obtained with the GFZ solution in Fennoscandia and with the CSR solution in North America. With radial gravity rates in excellent agreement with GPS uplift rates, more information on the GIA process can be extracted from GRACE gravity field solutions in the form of tangential gravity rates, which are equivalent to a rate of change in the deflection of the vertical scaled by the magnitude of gravity rate vector. Tangential gravity rates derived from GRACE point towards the centre of the previously glaciated area, and are largest in a location close to the centre of the former ice sheet. Forward modelling showed that present day tangential gravity rates have maximum sensitivity between the centre and edge of the former ice sheet, while radial gravity 8. Glacial isostatic adjustment and sea-level change. State of the art report International Nuclear Information System (INIS) Whitehouse, Pippa 2009-04-01 This report outlines the physics of glacial isostatic adjustment (GIA), how this affects sea-level, and the methods which are employed by researchers to study and understand these processes. The report describes the scientific background into the processes and methods presented in SKB TR-06-23 (INIS ref 38-021351). The purpose of this report is to provide a reference document for people who require a more in-depth understanding of GIA processes than is presented in the earlier report. The key components of the GIA system are described, and this is followed by a concise description of the processes that take place within and between these components during a glacial cycle. The report contains 4 chapters: Chapter 1, 'Introduction'; Chapter 2, 'GIA systems', describes the three main systems which are involved in the GIA process; the solid Earth, the hydrosphere and the cryosphere. The various parameters which govern the behaviour of these systems, and must be known in order to model GIA processes, are defined. Chapter 3, 'Governing equations', lays out the physics of GIA and derives the equations which must be solved to determine the redistribution of water over the surface of the Earth, and the solid Earth response. Secondary processes, such as ocean syphoning, are also described. The driving forces behind glacial cycles are briefly discussed. The methods used to solve these equations are laid out in chapter 4, 'State-of-the-art GIA models'. In this chapter, the different approaches used by different groups of researchers are discussed, as are the relative accuracy of the methods. Recent improvements to the theory are described, as are current shortcomings of the models. The various data sets used to calibrate and verify the accuracy of the modelling are also briefly described in this chapter. In the past few years advances in computational speed have enabled researchers to develop models which attempt to account for the effects 3-D Earth structure upon GIA processes 9. The influence of lateral Earth structure on glacial isostatic adjustment in Greenland Science.gov (United States) Milne, Glenn A.; Latychev, Konstantin; Schaeffer, Andrew; Crowley, John W.; Lecavalier, Benoit S.; Audette, Alexandre 2018-05-01 We present the first results that focus on the influence of lateral Earth structure on Greenland glacial isostatic adjustment (GIA) using a model that can explicitly incorporate 3-D Earth structure. In total, eight realisations of lateral viscosity structure were developed using four global seismic velocity models and two global lithosphere (elastic) thickness models. Our results show that lateral viscosity structure has a significant influence on model output of both deglacial relative sea level (RSL) changes and present-day rates of vertical land motion. For example, lateral structure changes the RSL predictions in the Holocene by several 10 s of metres in many locations relative to the 1-D case. Modelled rates of vertical land motion are also significantly affected, with differences from the 1-D case commonly at the mm/yr level and exceeding 2 mm/yr in some locations. The addition of lateral structure was unable to account for previously identified data-model RSL misfits in northern and southern Greenland, suggesting limitations in the adopted ice model (Lecavalier et al. 2014) and/or the existence of processes not included in our model. Our results show large data-model discrepancies in uplift rates when applying a 1-D viscosity model tuned to fit the RSL data; these discrepancies cannot be reconciled by adding the realisations of lateral structure considered here. In many locations, the spread in model output for the eight different 3-D Earth models is of similar amplitude or larger than the influence of lateral structure (as defined by the average of all eight model runs). This reflects the differences between the four seismic and two lithosphere models used and implies a large uncertainty in defining the GIA signal given that other aspects that contribute to this uncertainty (e.g. scaling from seismic velocity to viscosity) were not considered in this study. In order to reduce this large model uncertainty, an important next step is to develop more accurate 10. Use of GRACE determined secular gravity rates for glacial isostatic adjustment studies in North-America Science.gov (United States) van der Wal, Wouter; Wu, Patrick; Sideris, Michael G.; Shum, C. K. 2008-10-01 Monthly geopotential spherical harmonic coefficients from the GRACE satellite mission are used to determine their usefulness and limitations for studying glacial isostatic adjustment (GIA) in North-America. Secular gravity rates are estimated by unweighted least-squares estimation using release 4 coefficients from August 2002 to August 2007 provided by the Center for Space Research (CSR), University of Texas. Smoothing is required to suppress short wavelength noise, in addition to filtering to diminish geographically correlated errors, as shown in previous studies. Optimal cut-off degrees and orders are determined for the destriping filter to maximize the signal to noise ratio. The halfwidth of the Gaussian filter is shown to significantly affect the sensitivity of the GRACE data (with respect to upper mantle viscosity and ice loading history). Therefore, the halfwidth should be selected based on the desired sensitivity. It is shown that increase in water storage in an area south west of Hudson Bay, from the summer of 2003 to the summer of 2006, contributes up to half of the maximum estimated gravity rate. Hydrology models differ in the predictions of the secular change in water storage, therefore even 4-year trend estimates are influenced by the uncertainty in water storage changes. Land ice melting in Greenland and Alaska has a non-negligible contribution, up to one-fourth of the maximum gravity rate. The estimated secular gravity rate shows two distinct peaks that can possibly be due to two domes in the former Pleistocene ice cover: west and south east of Hudson Bay. With a limited number of models, a better fit is obtained with models that use the ICE-3G model compared to the ICE-5G model. However, the uncertainty in interannual variations in hydrology models is too large to constrain the ice loading history with the current data span. For future work in which GRACE will be used to constrain ice loading history and the Earth's radial viscosity profile, it is 11. Glacial isostatic adjustment and sea-level change. State of the art report Energy Technology Data Exchange (ETDEWEB) Whitehouse, Pippa (Durham Univ., Dept. of Geography, Durham (United Kingdom)) 2009-04-15 This report outlines the physics of glacial isostatic adjustment (GIA), how this affects sea-level, and the methods which are employed by researchers to study and understand these processes. The report describes the scientific background into the processes and methods presented in SKB TR-06-23 (INIS ref 38-021351). The purpose of this report is to provide a reference document for people who require a more in-depth understanding of GIA processes than is presented in the earlier report. The key components of the GIA system are described, and this is followed by a concise description of the processes that take place within and between these components during a glacial cycle. The report contains 4 chapters: Chapter 1, 'Introduction'; Chapter 2, 'GIA systems', describes the three main systems which are involved in the GIA process; the solid Earth, the hydrosphere and the cryosphere. The various parameters which govern the behaviour of these systems, and must be known in order to model GIA processes, are defined. Chapter 3, 'Governing equations', lays out the physics of GIA and derives the equations which must be solved to determine the redistribution of water over the surface of the Earth, and the solid Earth response. Secondary processes, such as ocean syphoning, are also described. The driving forces behind glacial cycles are briefly discussed. The methods used to solve these equations are laid out in chapter 4, 'State-of-the-art GIA models'. In this chapter, the different approaches used by different groups of researchers are discussed, as are the relative accuracy of the methods. Recent improvements to the theory are described, as are current shortcomings of the models. The various data sets used to calibrate and verify the accuracy of the modelling are also briefly described in this chapter. In the past few years advances in computational speed have enabled researchers to develop models which attempt to account for the 12. Energy flux of hot atoms International Nuclear Information System (INIS) Wotzak, G.P.; Kostin, M.D. 1976-01-01 The process in which hot atoms collide with thermal atoms of a gas, transfer kinetic energy to them, and produce additional hot atoms is investigated. A stochastic method is used to obtain numerical results for the spatial and time dependent energy flux of hot atoms in a gas. The results indicate that in hot atom systems a front followed by an intense energy flux of hot atoms may develop 13. HotRegion: a database of predicted hot spot clusters. Science.gov (United States) Cukuroglu, Engin; Gursoy, Attila; Keskin, Ozlem 2012-01-01 Hot spots are energetically important residues at protein interfaces and they are not randomly distributed across the interface but rather clustered. These clustered hot spots form hot regions. Hot regions are important for the stability of protein complexes, as well as providing specificity to binding sites. We propose a database called HotRegion, which provides the hot region information of the interfaces by using predicted hot spot residues, and structural properties of these interface residues such as pair potentials of interface residues, accessible surface area (ASA) and relative ASA values of interface residues of both monomer and complex forms of proteins. Also, the 3D visualization of the interface and interactions among hot spot residues are provided. HotRegion is accessible at http://prism.ccbb.ku.edu.tr/hotregion. 14. HOT GAS HALOS IN EARLY-TYPE FIELD GALAXIES International Nuclear Information System (INIS) Mulchaey, John S.; Jeltema, Tesla E. 2010-01-01 We use Chandra and XMM-Newton to study the hot gas content in a sample of field early-type galaxies. We find that the L X -L K relationship is steeper for field galaxies than for comparable galaxies in groups and clusters. The low hot gas content of field galaxies with L K ∼ * suggests that internal processes such as supernovae-driven winds or active galactic nucleus feedback expel hot gas from low-mass galaxies. Such mechanisms may be less effective in groups and clusters where the presence of an intragroup or intracluster medium can confine outflowing material. In addition, galaxies in groups and clusters may be able to accrete gas from the ambient medium. While there is a population of L K ∼ * galaxies in groups and clusters that retain hot gas halos, some galaxies in these rich environments, including brighter galaxies, are largely devoid of hot gas. In these cases, the hot gas halos have likely been removed via ram pressure stripping. This suggests a very complex interplay between the intragroup/intracluster medium and hot gas halos of galaxies in rich environments, with the ambient medium helping to confine or even enhance the halos in some cases and acting to remove gas in others. In contrast, the hot gas content of more isolated galaxies is largely a function of the mass of the galaxy, with more massive galaxies able to maintain their halos, while in lower mass systems the hot gas escapes in outflowing winds. 15. Hot-Film and Hot-Wire Anemometry for a Boundary Layer Active Flow Control Test Science.gov (United States) Lenahan, Keven C.; Schatzman, David M.; Wilson, Jacob Samuel 2013-01-01 Unsteady active flow control (AFC) has been used experimentally for many years to minimize bluff-body drag. This technology could significantly improve performance of rotorcraft by cleaning up flow separation. It is important, then, that new actuator technologies be studied for application to future vehicles. A boundary layer wind tunnel was constructed with a 1ft-x-3ft test section and unsteady measurement instrumentation to study how AFC manipulates the boundary layer to overcome adverse pressure gradients and flow separation. This unsteady flow control research requires unsteady measurement methods. In order to measure the boundary layer characteristics, both hot-wire and hot-film Constant Temperature Anemometry is used. A hot-wire probe is mounted in the flow to measure velocity while a hot-film array lays on the test surface to measure skin friction. Hot-film sensors are connected to an anemometer, a Wheatstone bridge circuit with an output that corresponds to the dynamic flow response. From this output, the time varying flow field, turbulence, and flow reversal can be characterized. Tuning the anemometers requires a fan test on the hot-film sensors to adjust each output. This is a delicate process as several variables drastically affect the data, including control resistance, signal input, trim, and gain settings. 16. The effect of hot isostatic pressing on the microstructure and tensile properties of an unmodified A356-T6 cast aluminum alloy International Nuclear Information System (INIS) Ran Guang; Zhou Jingen; Wang, Q.G. 2006-01-01 In this paper, the effect of HIPping process on the microstructure and tensile properties of an unmodified sand cast A356-T6 aluminum alloy was studied. The microstructure and tensile fracture surfaces of the alloy were examined by transmission electron microscope (TEM), scanning electron microscope (SEM) and optical microscope. The results show that sub-grain boundaries are formed by HIPping process, and some silicon precipitates are formed at the sub-grain boundaries during aging hardening. The needle-shape precipitates are Mg 2 Si particles according to SED pattern analysis. The lattice misfit between Mg 2 Si and aluminum matrix is about 0.256% for [111] Al //[410] Mg 2 Si HIPping process significantly reduces porosity volume fraction and pore sizes and thus improves ductility. However, the tensile strength is improved very marginally due to the brittle nature of the unmodified coarse microstructure. The sub-grain boundary formed in the HIPping process has not shown significant influence on the tensile properties. For the studied alloy with large secondary dendrite arm spacing (SDAS) (above 80μm), the tensile fracture exhibits a transgranular mode (along the cell boundaries) with quasi-cleavage feature 17. HIP (hot isostatic pressing) sintering of Tantalum (Ta) and tantalum carbide (TaC) powder mixture: relations between microstructure and properties International Nuclear Information System (INIS) Valin, F.; Schnedecker, M. 1994-01-01 HIP sintering at 1630 C and 195 MPa, during 2 hours, can be used for complete densification of mixtures of commercial tantalum carbide and tantalum powders. HIPed material properties are depending upon initial compositions. For C/Ta ratios inferior to 80%, the monocarbide structure is preserved. A partial ordering of the carbon vacancies will result, for TaC(0.80), in microhardness maximization. The microstructurally homogenous TaC(0.45) shows an excellent toughness. 2 figs., 2 refs 18. Effect of zirconium addition on the microstructure and mechanical properties of 15Cr-ODS ferritic Steels consolidated by hot isostatic pressing Energy Technology Data Exchange (ETDEWEB) Xu, Haijian, E-mail: [email protected] [Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education, Northeastern University, Shenyang 110819 (China); Material Science and Engineering, Faculty of Engineering, Hokkaido University, Sapporo 060-8628 (Japan); Lu, Zheng; Wang, Dongmei; Liu, Chunming [Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education, Northeastern University, Shenyang 110819 (China) 2017-01-15 The influence of Zr addition on the microstructure and mechanical properties of mechanically alloyed (MA) ODS ferritic steels were studied in this work. The microstructure characteristics included the grain size, oxide particles number densities, size distributions, crystal structures and compositions. TEM foils measurements were complemented by studies of alloys on carbon extraction replica and focus ion beam (FIB) foils. The tensile properties were carried out at different temperatures. The microstructure and mechanical properties were analyzed and compared with nominal compositions (wt.%): Fe-15Cr-2W-0.3Y{sub 2}O{sub 3} and Fe-15Cr −2W-0.3Zr-0.3Y{sub 2}O{sub 3}. The experimental revealed that the addition of Zr increased the volume fraction of the smallest and equiaxed ferritic grains, number density of nano-oxide particles and decreased the average size of oxide particles within the ferritic matrix, promoting the formation of fine trigonal δ-phase Y{sub 4}Zr{sub 3}O{sub 12} nano-oxides and leading to the enhancement of the mechanical properties of the ODS steels. 19. Fabrication of Polycrystalline Transparent Co+2: MgAl2O4 by a Combination of Spark Plasma Sintering (SPS and Hot Isostatic Pressing (HIP Processes Directory of Open Access Journals (Sweden) Sokol Maxim 2017-01-01 Full Text Available Transparent Co2+ doped MgAl2Ob4 spinel was fabricated by SPS consolidation followed by and HIP treatment. It was established that HIP treatment significantly improved transparency of the ceramic in a wide range of wavelengths, especially, in a range, which is relevant for Q-switching. Nonlinear absorption was demonstrated and the ground and excited state absorption cross sections were estimated. The positive effect of the HIP treatment on the optical properties is related to an elimination of extremely fine porosity and to the location of Co ions at Mg2+sites in the spinel ionic structure. The experimental results indicate that the fabricated specimens can be used as a passive laser Q-switching material. 20. Investigation of the High-Cycle Fatigue Life of Selective Laser Melted and Hot Isostatically Pressed Ti-6Al-4v Science.gov (United States) 2015-03-26 marketed for production of parts with metal alloys: electron-beam melting and laser sintering (LS) [3, 10, 36]. The primary distinction between EBM and LS...staircase method described in ASTM STP 588 [68]. The first specimen in a staircase test is tested at a maximum stress level corresponding to the 1. Hot Laboratories and Remote Handling International Nuclear Information System (INIS) 2007-01-01 a metallic precipitates in an irradiated simulated fuel' by Jung Yang-Hong, 'Detritiation of tiles from tokamaks by laser cleaning' presented by J. Paul Coad et al., 'Experience feedback on the refurbishment of the LECA hot laboratory at Cadarache' by Jean-Paul Grandjean et al., 'New device for X-ray diffraction analyses of irradiated materials' by Christophe Valot et al., 'Tensile testings and metallographic examination on irradiated CANDU pressure tube specimens' by Silviu Ionescu et al., 'Separation and determination of actinides from spent nuclear fuel solution by alpha spectrometry' by Ana Matei et al., 'Experiments for separation and purification of 99 Mo from uranium solutions with fission products as tracers' by Gabriela Androne et al., 'Iodine induced stress corrosion cracking and axial creep: 2 new cladding testing facilities at Leci laboratory' by Quentin Auzoux et al., 'Development of a gas trapping system for fission products xenon and krypton throughout dissolution of irradiated targets and fuels in hot cells' by Pierrick Menegon et al., and finally, 'Post-irradiation-examination of irradiated fuel outside the hot cell' by Dawn E. Janney 2. Particulate hot gas stream cleanup technical issues Energy Technology Data Exchange (ETDEWEB) Pontius, D.H.; Snyder, T.R. 1999-09-30 The analyses of hot gas stream cleanup particulate samples and descriptions of filter performance studied under this contract were designed to address problems with filter operation that have been linked to characteristics of the collected particulate matter. One objective of this work was to generate an interactive, computerized data bank of the key physical and chemical characteristics of ash and char collected from operating advanced particle filters and to relate these characteristics to the operation and performance of these filters. The interactive data bank summarizes analyses of over 160 ash and char samples from fifteen pressurized fluidized-bed combustion and gasification facilities utilizing high-temperature, high pressure barrier filters. 3. Oxide formation and precipitation behaviors on interface of F82H steel joints during HIPing and hot pressing International Nuclear Information System (INIS) Kishimoto, H.; Ono, T.; Sakasegawa, H.; Tanigawa, H.; Ando, M.; Shibayama, T.; Kohno, Y.; Kohyama, A. 2013-01-01 Joining technologies for F82H steels are important issues for the development of fusion energy. The hot isostatic pressing (HIP) method is appropriate for consolidating the first wall of the blanket because of the flexibility of the shape of HIPed products. The HIP method is planned for fabricating a complex-shaped first wall component with built-in cooling channels; thus, accumulation of studies of microstructural and mechanical property changes, especially lower toughness of the HIPed joints, is essential. Present research aims to reveal the microstructural evolution of F82H joints fabricated by the HIP method compared with joints fabricated by hot pressing, focusing on the formation of oxides on the interface. F82H joints were characterized using 1/3-scale Charpy V-notch impact test, transmission electron microscope, scanning electron microscope, and electron probe analysis to survey the microstructural characteristics of the interface 4. Status of the development of hot gas ducts for HTRs International Nuclear Information System (INIS) Stehle, H.; Klas, E. 1984-01-01 In the PNP nuclear process heat system the heat generated in the helium cooled core is transferred to the steam reformer and to the successive steam generator or to the intermediate heat exchanger by the primary helium via suitable hot gas ducts. The heat is carried over to the steam gasifier by the intermediate heat exchanger and a secondary helium loop. In both the primary and the secondary loop, the hot gas ducts are internally insulated by a ceramic fibre insulation to protect the support tube and the pressure housing from the high helium temperatures. A graphite hot gas liner will be used for the coaxial primary duct with an annular gap between support tube and pressure shell for the cold gas counterflow. A metallic hot gas liner will be installed in the secondary duct 5. Extensional fault geometry and its flexural isostatic response during the formation of the Iberia - Newfoundland conjugate rifted margins Science.gov (United States) Gómez-Romeu, Júlia; Kusznir, Nick; Manatschal, Gianreto; Roberts, Alan 2017-04-01 Despite magma-poor rifted margins having been extensively studied for the last 20 years, the evolution of extensional fault geometry and the flexural isostatic response to faulting remain still debated topics. We investigate how the flexural isostatic response to faulting controls the structural development of the distal part of rifted margins in the hyper-extended domain and the resulting sedimentary record. In particular we address an important question concerning the geometry and evolution of extensional faults within distal hyper-extended continental crust; are the seismically observed extensional fault blocks in this region allochthons from the upper plate or are they autochthons of the lower plate? In order to achieve our aim we focus on the west Iberian rifted continental margin along the TGS and LG12 seismic profiles. Our strategy is to use a kinematic forward model (RIFTER) to model the tectonic and stratigraphic development of the west Iberia margin along TGS-LG12 and quantitatively test and calibrate the model against breakup paleo-bathymetry, crustal basement thickness and well data. RIFTER incorporates the flexural isostatic response to extensional faulting, crustal thinning, lithosphere thermal loads, sedimentation and erosion. The model predicts the structural and stratigraphic consequences of recursive sequential faulting and sedimentation. The target data used to constrain model predictions consists of two components: (i) gravity anomaly inversion is used to determine Moho depth, crustal basement thickness and continental lithosphere thinning and (ii) reverse post-rift subsidence modelling consisting of flexural backstripping, decompaction and reverse post-rift thermal subsidence modelling is used to give paleo-bathymetry at breakup time. We show that successful modelling of the structural and stratigraphic development of the TGS-LG12 Iberian margin transect also requires the simultaneous modelling of the Newfoundland conjugate margin, which we 6. Coupling intensity and isostatic competition between subducting slab and overriding plate control trench motions and tectonics of the overriding plate Science.gov (United States) Wu, G.; Moresi, L. N. 2017-12-01 Trench motions not only reflect tectonic regimes on the overriding plate but also shed light on the competition between subducting slab and overriding plate, however, major controls over trench advance or retreat and their consequences are still illusive. We use 2D thermo-mechanical experiments to study the problem. We find that the coupling intensity particularly in the uppermost 200 km and the isostatic competition between subducting slab and overriding plate largely determine trench motion and tectonics of in the overriding plate. Coupling intensity is the result of many contributing factors, including frictional coefficient of brittle part of the subducting interface and the viscosity of the ductile part, thermal regime and rheology of the overriding plate, and water contents and magmatic activity in the subducting slab and overriding plate. In this study, we are not concerned with the dynamic evolution of individual controlling parameter but simply use effective media. For instance, we impose simple model parameters such as frictional coefficient and vary the temperature and strain-rate dependent viscosity of the weak layer between the subducting slab and overriding plate. In the coupled end-member case, strong coupling leads to strong corner flow, depth-dependent compression/extension, and mantle return flow on the overriding plate side. It results in fast trench retreat, broad overriding plate extension, and even slab breakoff. In the decoupled end-member case, weak coupling causes much weaker response on the overriding plate side compared with the coupled end-member case, and the subducting slab can be largely viewed as a conveyer belt. We find that the isostatic competition between the subducting slab and overriding plate also has a major control over trench motion, and may better be viewed in 3D models. This is consistent with the findings in previous 3D studies that trench motion is most pronounced close to the slab edge. Here we propose that the 7. Multifragmentation of hot nuclei International Nuclear Information System (INIS) Tamain, B. 1990-10-01 It is difficult to deposit a large amount (∼ 1 Gev) of excitation energy into a nucleus. And if one wants to deposit large excitation energy values, the best way consists of shooting a given target nucleus with several nucleons, which can be achieved by using intermediate energy (10-100 MeV/nucleon) heavy ions. Such very excited objects were named hot nuclei. The study of hot nuclei has been undertaken only for 7 years because intermediate energy heavy ion facilities were not available before. The game is then to determine the decay properties of such nuclei, their limits of existence. Their study is connected with general properties of nuclear matter: namely its equation of state. Of special interest, is the onset of a new decay mechanism: multifragmentation, which is the non-sequential disassembly of a hot nucleus into several light nuclei (often called intermediate-mass fragments or IMF) or particles. This paper, shows how this mechanism can reflect fundamental properties of nuclear matter, but also how its experimental signature is difficult to establish. Multifragmentation has also been studied by using very energetic projectiles (protons and heavy ions) in the relativistic or ultra-relativistic region. The multifragmentation question of hot nuclei is far from being solved. One knows that IMF production increases when the excitation energy brought into a system is strongly increased, but very little is known about the mechanisms involved and a clear onset for multifragmentation is not established 8. Utilizing hot electrons Energy Technology Data Exchange (ETDEWEB) Nozik, Arthur J. 2018-03-01 In current solar cells, any photon energy exceeding the semiconductor bandgap is lost before being collected, limiting the cell performance. Hot carrier solar cells could avoid these losses. Now, a detailed experimental study and analysis shows that this strategy could lead to an improvement of the photoconversion efficiency in practice. 9. Mechanical shielded hot cell International Nuclear Information System (INIS) Higgy, H.R.; Abdel-Rassoul, A.A. 1983-01-01 A plan to erect a mechanical shielded hot cell in the process hall of the Radiochemical Laboratory at Inchas is described. The hot cell is designed for safe handling of spent fuel bundles, from the Inchas reactor, and for dismantling and cutting the fuel rods in preparation for subsequent treatment. The biological shielding allows for the safe handling of a total radioactivity level up to 10,000 MeV-Ci. The hot cell consists of an α-tight stainless-steel box, connected to a γ-shielded SAS, through an air-lock containing a movable carriage. The α-box is tightly connected with six dry-storage cavities for adequate storage of the spent fuel bundles. Both the α-box, with the dry-storage cavities, and the SAS are surrounded by 200-mm thick biological lead shielding. The α-box is equipped with two master-slave manipulators, a lead-glass window, a monorail crane and Padirac and Minirag systems. The SAS is equipped with a lead-glass window, tong manipulator, a shielded pit and a mechanism for the entry of the spent fuel bundle. The hot cell is served by adequate ventilation and monitoring systems. (author) 10. Hot wire TIG temper bead welding for nuclear repairs International Nuclear Information System (INIS) Lambert, J.A.; Gilston, P.F. 1989-08-01 A preliminary assessment has been carried out to determine the suitability of the hot wire tungsten inert gas (TIG) welding process for the repair of thick section, ferritic steel nuclear pressure vessels. The objective has been to identify a hot wire TIG temper bead procedure, suitable for repairs without post weld heat treatment. This procedure involves depositing two weld layers with carefully selected welding parameters such that overlapping thermal cycles produce a refined and tempered heat affected zone, HAZ, microstructure. (author) 11. Simplified numerical simulation of hot channel in sodium cooled reactor International Nuclear Information System (INIS) Fonseca, F. de A.S. da; Silva Filho, E. 1988-12-01 The thermal-hydraulic parameter values that restrict the operation of a liquid sodium cooled reactor are not established by the average conditions of the coolant in the reactor core but by the extreme conditions of the hot channel. The present work was developed to analysis of hot channel of a sodium cooled reactor, adapting to this reactor an existent simplified model for hot channel of pressurized water reactor. The model was applied for a standard sodium reactor and the results are considered satisfatory. (author) [pt 12. Hot Deformation Behavior of Hot-Extruded AA7175 Through Hot Torsion Tests. Science.gov (United States) Lee, Se-Yeon; Jung, Taek-Kyun; Son, Hyeon-Woo; Kim, Sang-Wook; Son, Kwang-Tae; Choi, Ho-Joon; Oh, Sang-Ho; Lee, Ji-Woon; Hyun, Soong-Keun 2018-03-01 The hot deformation behavior of hot-extruded AA7175 was investigated with flow curves and processing maps through hot torsion tests. The flow curves and the deformed microstructures revealed that dynamic recrystallization (DRX) occurred in the hot-extruded AA7175 during hot working. The failure strain was highest at medium temperature. This was mainly influenced by the dynamic precipitation of fine rod-shaped MgZn2. The processing map determined the optimal deformation condition for the alloy during hot working. 13. Role of aging time on the magnetic properties of Sm2Co17 permanent magnets processed through cold isostatic pressing Science.gov (United States) Ramudu, M.; Rajkumar, D. M. 2018-04-01 The effect of aging time on the magnetic properties of Sm2Co17 permanent magnets processed through a novel method of cold isostatic pressing was investigated. Sintered Sm2Co17 samples were subjected to different aging times in the range of 10-30 h and their respective microstructures were correlated with the magnetic properties obtained. The values of remanant magnetization (Br) were observed to be constant in samples aged from 10-20 h beyond which a gradual decrease in Br values was observed. The values of coercivity (Hc) displayed a sharp increase in samples aged from 10 to 20 h beyond which the coercivity values showed marginal improvement. Hence a good combination of magnetic properties could be achieved in samples aged for 20 h. A maximum energy product of 27 MGOe was achieved in the 20 h aged sample processed through a novel route. 14. The effect of signal leakage and glacial isostatic rebound on GRACE-derived ice mass changes in Iceland DEFF Research Database (Denmark) Sørensen, Louise Sandberg; Jarosch, Alexander H.; Adalgeirsdottir, Gudfinna 2017-01-01 Monthly gravity field models from the GRACE satellite mission are widely used to determine ice mass changes of large ice sheets as well as smaller glaciers and ice caps. Here, we investigate in detail the ice mass changes of the Icelandic ice caps as derived from GRACE data. The small size...... of the Icelandic ice caps, their location close to other rapidly changing ice covered areas and the low viscosity of the mantle below Iceland make this especially challenging. The mass balance of the ice caps is well constrained by field mass balance measurements, making this area ideal for such investigations. We...... the Little Ice Age (∼ 1890 AD). To minimize the signal that leaks towards Iceland from Greenland, we employ an independent mass change estimate of the Greenland Ice Sheet derived from satellite laser altimetry. We also estimate the effect of post Little Ice Age glacial isostatic adjustment, from knowledge... 15. Software Simulation of Hot Tearing DEFF Research Database (Denmark) Andersen, S.; Hansen, P.N.; Hattel, Jesper Henri 1999-01-01 The brittleness of a solidifying alloy in a temperature range near the solidus temperature has been recognised since the fifties as the mechanism responsible for hot tearing. Due to this brittlenes, the metal will crack under even small amounts of strain in that temperature range. We see these hot...... tears in castings close to hot centres, where the level of strain is often too high.Although the hot tearing mechanism is well understood, until now it has been difficult to do much to reduce the hot tearing tendency in a casting. In the seventies, good hot tearing criteria were developed by considering...... the solidification rate and the strain rate of the hot tear prone areas. But, until recently it was only possible to simulate the solidification rate, so that the criteria could not be used effectively.Today, with new software developments, it is possible to also simulate the strain rate in the hot tear prone areas... 16. Hot Fuel Examination Facility (HFEF) Data.gov (United States) Federal Laboratory Consortium — The Hot Fuel Examination Facility (HFEF) is one of the largest hot cells dedicated to radioactive materials research at Idaho National Laboratory (INL). The nation's... 17. Effect of hot pressing additives on the leachability of hot pressed sodium hydrous titanium oxide International Nuclear Information System (INIS) Valentine, T.M.; Sambell, R.A.J. 1980-01-01 Sodium hydrous titanium oxide is an ion exchange resin which can be used for immobilizing medium level waste (MLW) liquors. When hot pressed, it undergoes conversion to a ceramic. Three low melting point materials (borax, bismuth trioxide, and a mixture of PbO/CuO) were added to the (Na)HTiO and the effect that each of these had on aiding densification was assessed. Hot pressing temperature, applied pressure, and percentage addition of hot pressing aid were varied. Percentage open porosity, flexural strength, and leachability were measured. There was a linear relationship between the percentage open porosity and the logarithm of the leach rate for a constant percentage addition of each additive 18. Lithospheric thickness jumps at the S-Atlantic continental margins from satellite gravity data and modelled isostatic anomalies Science.gov (United States) Shahraki, Meysam; Schmeling, Harro; Haas, Peter 2018-01-01 Isostatic equilibrium is a good approximation for passive continental margins. In these regions, geoid anomalies are proportional to the local dipole moment of density-depth distributions, which can be used to constrain the amount of oceanic to continental lithospheric thickening (lithospheric jumps). We consider a five- or three-layer 1D model for the oceanic and continental lithosphere, respectively, composed of water, a sediment layer (both for the oceanic case), the crust, the mantle lithosphere and the asthenosphere. The mantle lithosphere is defined by a mantle density, which is a function of temperature and composition, due to melt depletion. In addition, a depth-dependent sediment density associated with compaction and ocean floor variation is adopted. We analyzed satellite derived geoid data and, after filtering, extracted typical averaged profiles across the Western and Eastern passive margins of the South Atlantic. They show geoid jumps of 8.1 m and 7.0 m for the Argentinian and African sides, respectively. Together with topography data and an averaged crustal density at the conjugate margins these jumps are interpreted as isostatic geoid anomalies and yield best-fitting crustal and lithospheric thicknesses. In a grid search approach five parameters are systematically varied, namely the thicknesses of the sediment layer, the oceanic and continental crusts and the oceanic and the continental mantle lithosphere. The set of successful models reveals a clear asymmetry between the South Africa and Argentine lithospheres by 15 km. Preferred models predict a sediment layer at the Argentine margin of 3-6 km and at the South Africa margin of 1-2.5 km. Moreover, we derived a linear relationship between, oceanic lithosphere, sediment thickness and lithospheric jumps at the South Atlantic margins. It suggests that the continental lithospheres on the western and eastern South Atlantic are thicker by 45-70 and 60-80 km than the oceanic lithospheres, respectively. 19. Hot subluminous star: HDE 283048 International Nuclear Information System (INIS) Laget, M.; Vuillemin, A.; Parsons, S.B.; Henize, K.G.; Wray, J.D. 1978-01-01 The star HDE 283048, located at α = 3/sup h/50/sup m/.3, delta = +25 0 36', shows a strong ultraviolet continuum. Ground-based observations indicate a hot-dominated composite spectrum. Several lines of evidence suggest that the hot component is a hot subdwarf. 2 figures 20. BETHSY ISP-38 flow behaviour in hot leg International Nuclear Information System (INIS) Petelin, S.; Jurkovic, M. 1998-01-01 Betsy Test 6.9c OECD ISP-38 RELAP5/MOD3.2 input model was developed and simulation performed for loss of RHR system during mid-loop operation. Initial liquid level in RCS was at horizontal axis of the hot legs. Pressurizer and steam generator manways were opened 1 s after the transient was initiated. Secondary side is full of air and isolated. Results of calculations were satisfied except in surge line and in pressurizer where larger amount of water is presented. Liquid was entrained in that part of the system during bubbly or varies stratified flow in the hot leg. Due to non-physical results in hot leg pipe with connected surge line and pressurizer, RELAP5 horizontal stratification model deficiencies was studied and possible improvements investigated.(author) 1. Annealing effects on the microstructure and mechanical properties of hot-rolled 14Cr-ODS steel International Nuclear Information System (INIS) Gao, R.; Zhang, T.; Ding, H.L.; Jiang, Y.; Wang, X.P.; Fang, Q.F.; Liu, C.S. 2015-01-01 The oxide dispersion strengthened ferritic steels with nominal composition (weight percent) of Fe–14Cr–2W-0.5Ti-0.06Si-0.2V-0.1Mn-0.05Ta-0.03C-0.3Y_2O_3 were fabricated by sol–gel method, mechanical alloying, and hot isostatic pressing techniques. The evolution of microstructure and mechanical properties of the hot-rolled specimens with heat treatment was investigated. Tensile strength and hardness of hot-rolled ODS steel are significantly enhanced due to the formation of mechanical twins and high density dislocations. Uniformly dispersed oxide particles (10–40 nm) and fine-grained structure (200–400 nm) are responsible for the superior mechanical properties of the hot-rolled specimen annealed between 650 °C and 850 °C. With further increasing annealing temperature, the grain size of the hot-rolled specimens increases while the size of oxide particles decreases, which leads to lower strength and hardness but better ductility. The tensile strength and total elongation of samples in the rolling direction are higher than those in the transverse direction after the same treatments owing to the grain anisotropy induced by the large mechanical deformation. 2. Annealing effects on the microstructure and mechanical properties of hot-rolled 14Cr-ODS steel Science.gov (United States) Gao, R.; Zhang, T.; Ding, H. L.; Jiang, Y.; Wang, X. P.; Fang, Q. F.; Liu, C. S. 2015-10-01 The oxide dispersion strengthened ferritic steels with nominal composition (weight percent) of Fe-14Cr-2W-0.5Ti-0.06Si-0.2V-0.1Mn-0.05Ta-0.03C-0.3Y2O3 were fabricated by sol-gel method, mechanical alloying, and hot isostatic pressing techniques. The evolution of microstructure and mechanical properties of the hot-rolled specimens with heat treatment was investigated. Tensile strength and hardness of hot-rolled ODS steel are significantly enhanced due to the formation of mechanical twins and high density dislocations. Uniformly dispersed oxide particles (10-40 nm) and fine-grained structure (200-400 nm) are responsible for the superior mechanical properties of the hot-rolled specimen annealed between 650 °C and 850 °C. With further increasing annealing temperature, the grain size of the hot-rolled specimens increases while the size of oxide particles decreases, which leads to lower strength and hardness but better ductility. The tensile strength and total elongation of samples in the rolling direction are higher than those in the transverse direction after the same treatments owing to the grain anisotropy induced by the large mechanical deformation. 3. Modeling Hot-Spot Contributions in Shocked High Explosives at the Mesoscale Energy Technology Data Exchange (ETDEWEB) Harrier, Danielle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States) 2015-08-12 When looking at performance of high explosives, the defects within the explosive become very important. Plastic bonded explosives, or PBXs, contain voids of air and bonder between the particles of explosive material that aid in the ignition of the explosive. These voids collapse in high pressure shock conditions, which leads to the formation of hot spots. Hot spots are localized high temperature and high pressure regions that cause significant changes in the way the explosive material detonates. Previously hot spots have been overlooked with modeling, but now scientists are realizing their importance and new modeling systems that can accurately model hot spots are underway. 4. Hot chocolate effect International Nuclear Information System (INIS) Crawford, F.S. 1982-01-01 The ''hot chocolate effect'' was investigated quantitatively, using water. If a tall glass cylinder is filled nearly completely with water and tapped on the bottom with a softened mallet one can detect the lowest longitudinal mode of the water column, for which the height of the water column is one-quarter wavelength. If the cylinder is rapidly filled with hot tap water containing dissolved air the pitch of that mode may descend by nearly three octaves during the first few seconds as the air comes out of solution and forms bubbles. Then the pitch gradually rises as the bubbles float to the top. A simple theoretical expression for the pitch ratio is derived and compared with experiment. The agreement is good to within the 10% accuracy of the experiments 5. Hot water reticulation Energy Technology Data Exchange (ETDEWEB) Fellows, S. K. 1977-10-15 Hot water reticulation (district heating) is an established method of energy supply within cities in many countries. It is based on the fact that heat can often be obtained cheaply in bulk, and that the resultant savings can, in suitable circumstances, justify the investment in a reticulation network of insulated pipes to distribute the heat to many consumers in the form of hot water or occasionally steam. The heat can be used by domestic, commercial, and industrial consumers for space heating and water heating, and by industries for process heat. The costs of supplying domestic consumers can be determined by considering an average residential area, but industrial and commercial consumers are so varied in their requirements that every proposal must be treated independently. Fixed costs, variable costs, total costs, and demand and resource constraints are discussed. 6. The hot chocolate effect Science.gov (United States) Crawford, Frank S. 1982-05-01 The ''hot chocolate effect'' was investigated quantitatively, using water. If a tall glass cylinder is filled nearly completely with water and tapped on the bottom with a softened mallet one can detect the lowest longitudinal mode of the water column, for which the height of the water column is one-quarter wavelength. If the cylinder is rapidly filled with hot tap water containing dissolved air the pitch of that mode may descend by nearly three octaves during the first few seconds as the air comes out of solution and forms bubbles. Then the pitch gradually rises as the bubbles float to the top. A simple theoretical expression for the pitch ratio is derived and compared with experiment. The agreement is good to within the 10% accuracy of the experiments. 7. Hot air balloon engine Energy Technology Data Exchange (ETDEWEB) Edmonds, Ian [Solartran Pty Ltd, 12 Lentara Street, Kenmore, Brisbane 4069 (Australia) 2009-04-15 This paper describes a solar powered reciprocating engine based on the use of a tethered hot air balloon fuelled by hot air from a glazed collector. The basic theory of the balloon engine is derived and used to predict the performance of engines in the 10 kW to 1 MW range. The engine can operate over several thousand metres altitude with thermal efficiencies higher than 5%. The engine thermal efficiency compares favorably with the efficiency of other engines, such as solar updraft towers, that also utilize the atmospheric temperature gradient but are limited by technical constraints to operate over a much lower altitude range. The increased efficiency allows the use of smaller area glazed collectors. Preliminary cost estimates suggest a lower \$/W installation cost than equivalent power output tower engines. (author) 8. The ''hot'' patella International Nuclear Information System (INIS) Kipper, M.S.; Alazraki, N.P.; Feiglin, D.H. 1982-01-01 Increased patellar uptake on bone scans is seen quite commonly but the possible or probable etiologies of this finding have not been previously well described. A review of 100 consecutive bone scans showed that the incidence of bilateral ''hot'' patellae is 15%. Identified etiologies include osteoarthritic degenerative disease (35%), fracture, possible metastatic disease, bursitis, Paget's disease, and osteomyelitis. The value of careful history, physical examination, and radiographs is stressed 9. Hot nuclei and fragmentation International Nuclear Information System (INIS) Guerreau, D. 1993-01-01 A review is made of the present status concerning the production of nuclei above 5 MeV temperature. Considerable progress has been made recently on the understanding of the formation and the fate of such hot nuclei. It appears that the nucleus seems more stable against temperature than predicted by static calculations. However, the occurrence of multifragment production at high excitation energies is now well established. The various experimental features of the fragmentation process are discussed. (author) 59 refs., 12 figs 10. 'Hot particle' intercomparison dosimetry International Nuclear Information System (INIS) Kaurin, D.G.L.; Baum, J.W.; Charles, M.W.; Darley, D.P.J.; Durham, J.S.; Scannell, M.J.; Soares, C.G. 1996-01-01 Dosimetry measurements of four 'hot particles' were made at different density thickness values using five different methods. The hot particles had maximum dimensions of 650 μm and maximum beta energies of 0.97, 046, 0.36, and 0.32 MeV. Absorbers were used to obtain the dose at different depths for each dosimeter. Measurements were made using exoelectron dosimeters, an extrapolation chamber, NE Extremity Tape Dosimeters (tm), Eberline RO-2 and RO-2A survey meters, and two sets of GafChromic (tm) dye film with each set read out at a different institution. From these results the dose was calculated averaged over 1 cm 2 of tissue at 18, 70, 125, and 400 μm depth. Comparisons of tissue-dose averaged over 1 cm 2 for 18, 70, and 125 μm depth based on interpolated measured values, were within 30% for the GafChromic (tm) dye film, extrapolation chamber, NE Extremity Tape Dosimeters (tm), and Eberline RO-2 and 2A (tm) survey meters except for the hot particle with 0.46 MeV maximum beta energy. The results for this source showed differences of up to 60%. The extrapolation chamber and NE Extremity Tape dosimeters under-responded for measurements at 400 μm by about a factor of 2 compared with the GafChromic dye films for two hot particles with maximum beta energy of 0.32 and 0.36 MeV which each emitted two 100% 1 MeV photons per disintegration. Tissue doses determined using exoelectron dosimeters were a factor of 2 to 5 less than those determined using other dosimeters, possibly due to failures of the equipment. (author) 11. Solar Hot Water Heater Science.gov (United States) 1978-01-01 The solar panels pictured below, mounted on a Moscow, Idaho home, are part of a domestic hot water heating system capable of providing up to 100 percent of home or small business hot water needs. Produced by Lennox Industries Inc., Marshalltown, Iowa, the panels are commercial versions of a collector co-developed by NASA. In an effort to conserve energy, NASA has installed solar collectors at a number of its own facilities and is conducting research to develop the most efficient systems. Lewis Research Center teamed with Honeywell Inc., Minneapolis, Minnesota to develop the flat plate collector shown. Key to the collector's efficiency is black chrome coating on the plate developed for use on spacecraft solar cells, the coating prevents sun heat from "reradiating," or escaping outward. The design proved the most effective heat absorber among 23 different types of collectors evaluated in a Lewis test program. The Lennox solar domestic hot water heating system has three main components: the array of collectors, a "solar module" (blue unit pictured) and a conventional water heater. A fluid-ethylene glycol and water-is circulated through the collectors to absorb solar heat. The fluid is then piped to a double-walled jacket around a water tank within the solar module. 12. Pressure vessel failure at high internal pressure International Nuclear Information System (INIS) Laemmer, H.; Ritter, B. 1995-01-01 A RPV failure due to plastic instability was investigated using the ABAQUS finite element code together with a material model of thermal plasticity for large deformations. Not only rotational symmetric temperature distributions were studied, but also 'hot spots'. Calculations show that merely by the depletion of strength of the material - even at internal wall temperatures well below the melting point of the fuel elements of about 2000/2400 C - the critical internal pressure can decrease to values smaller than the operational pressure of 16 Mpa. (orig.) 13. Thermal stratification in the pressurizer International Nuclear Information System (INIS) Baik, S.J.; Lee, K.W.; Ro, T.S. 2001-01-01 The thermal stratification in the pressurizer due to the insurge from the hot leg to the pressurizer has been studied. The insurge flow of the cold water into the pressurizer takes place during the heatup/cooldown and the normal or abnormal transients during power operation. The pressurizer vessel can undergo significant thermal fatigue usage caused by insurges and outsurges. Two-dimensional axisymmetric transient analysis for the thermal stratification in the pressurizer is performed using the computational fluid dynamics code, FLUENT, to get the velocity and temperature distribution. Parametric study has been carried out to investigate the effect of the inlet velocity and the temperature difference between the hot leg and the pressurizer on the thermal stratification. The results show that the insurge flow of cold water into the pressurizer does not mix well with hot water, and the cold water remains only in the lower portion of the pressurizer, which leads to the thermal stratification in the pressurizer. The thermal load on the pressurizer due to the thermal stratification or the cyclic thermal transient should be examined with respect to the mechanical integrity and this study can serve the design data for the stress analysis. (authors) 14. Strength-ductility relationships in intermediate purity hot-pressed beryllium International Nuclear Information System (INIS) Stonehouse, A.J.; Bielawski, C.A.; Paine, R.M. 1977-01-01 The strength of vacuum hot-pressed, intermediate purity beryllium may be substantially increased without sacrifice of the strain capacity of the present grade (S-65) through decrease in the average grain size. Tensile strength of 517 MPa, 0.2% offset yield strength of 414 MPa with minimum 3% tensile elongation in all test directions could be commercially achieved. The tangent modulus of such material is quite attractive and suffers only about 10% degradation from room temperature to 260 0 C. The tangent modulus is dramatically enhanced by the presence of a yield point. The ductility of the materials studied did not appear to be affected by the BeO content across the range of 0.5 to 2.0% using nominal -44 to -15 μm powder particle sizes. All fine-grained pressings exhibited yield points in the as-pressed condition. Either full-density or sub-density hot-pressed billets given a hot isostatic pressing treatment without the use of cans showed only slight yield points after the HIP treatment with essentially the same strength and ductility factors as in the pressed condition. A plot of grain size vs yield strength in the as-pressed condition projects to an intercept with the fracture strength line at about 3 μm grain size. A similar plot after the HIP treatment shows a yield strength line parallel to the fracture strength line with no projected intercept predicting a completely brittle material. (author) 15. The effect of sediment loading in Fennoscandia and the Barents Sea during the last glacial cycle on glacial isostatic adjustment observations Directory of Open Access Journals (Sweden) W. van der Wal 2017-09-01 Full Text Available Models for glacial isostatic adjustment (GIA routinely include the effects of meltwater redistribution and changes in topography and coastlines. Since the sediment transport related to the dynamics of ice sheets may be comparable to that of sea level rise in terms of surface pressure, the loading effect of sediment deposition could cause measurable ongoing viscous readjustment. Here, we study the loading effect of glacially induced sediment redistribution (GISR related to the Weichselian ice sheet in Fennoscandia and the Barents Sea. The surface loading effect and its effect on the gravitational potential is modeled by including changes in sediment thickness in the sea level equation following the method of Dalca et al. (2013. Sediment displacement estimates are estimated in two different ways: (i from a compilation of studies on local features (trough mouth fans, large-scale failures, and basin flux and (ii from output of a coupled ice–sediment model. To account for uncertainty in Earth's rheology, three viscosity profiles are used. It is found that sediment transport can lead to changes in relative sea level of up to 2 m in the last 6000 years and larger effects occurring earlier in the deglaciation. This magnitude is below the error level of most of the relative sea level data because those data are sparse and errors increase with length of time before present. The effect on present-day uplift rates reaches a few tenths of millimeters per year in large parts of Norway and Sweden, which is around the measurement error of long-term GNSS (global navigation satellite system monitoring networks. The maximum effect on present-day gravity rates as measured by the GRACE (Gravity Recovery and Climate Experiment satellite mission is up to tenths of microgal per year, which is larger than the measurement error but below other error sources. Since GISR causes systematic uplift in most of mainland Scandinavia, including GISR in GIA models 16. Vacuum isostatic micro/macro molding of PTFE materials for laser beam shaping in environmental applications: large scale UV laser water purification Science.gov (United States) Lizotte, Todd; Ohar, Orest 2009-08-01 Accessibility to fresh clean water has determined the location and survival of civilizations throughout the ages [1]. The tangible economic value of water is demonstrated by industry's need for water in fields such as semiconductor, food and pharmaceutical manufacturing. Economic stability for all sectors of industry depends on access to reliable volumes of good quality water. As can be seen on television a nation's economy is seriously affected by water shortages through drought or mismanagement and as such those water resources must therefore be managed both for the public interest and the economic future. For over 50 years ultraviolet water purification has been the mainstay technology for water treatment, killing potential microbiological agents in water for leisure activities such as swimming pools to large scale waste water treatment facilities where the UV light photo-oxidizes various pollutants and contaminants. Well tailored to the task, UV provides a cost effective way to reduce the use of chemicals in sanitization and anti-biological applications. Predominantly based on low pressure Hg UV discharge lamps, the system is plagued with lifetime issues (~1 year normal operation), the last ten years has shown that the technology continues to advance and larger scale systems are turning to more advanced lamp designs and evaluating solidstate UV light sources and more powerful laser sources. One of the issues facing the treatment of water with UV lasers is an appropriate means of delivering laser light efficiently over larger volumes or cross sections of water. This paper examines the potential advantages of laser beam shaping components made from isostatically micro molding microstructured PTFE materials for integration into large scale water purification and sterilization systems, for both lamps and laser sources. Applying a unique patented fabrication method engineers can form micro and macro scale diffractive, holographic and faceted reflective structures 17. Emerging hot spot analysis DEFF Research Database (Denmark) Reinau, Kristian Hegner Traditionally, focus in the transport field, both politically and scientifically, has been on private cars and public transport. Freight transport has been a neglected topic. Recent years has seen an increased focus upon congestion as a core issue across Europe, resulting in a great need for know...... speed data for freight. Secondly, the analytical methods used, space-time cubes and emerging hot spot analysis, are also new in the freight transport field. The analysis thus estimates precisely how fast freight moves on the roads in Northern Jutland and how this has evolved over time.... 18. Multipurpose reprocessing hot cell International Nuclear Information System (INIS) Fletcher, R.D. 1975-01-01 A multipurpose hot cell is being designed for use at the Idaho Chemical Processing Plant for handling future scheduled fuels that cannot be adequately handled by the existing facilities and equipment. In addition to providing considerable flexibility to handle a wide variety of fuel sizes up to 2,500 lb in weight the design will provide for remote maintenance or replacement of the in-cell equipment with a minimum of exposure to personnel and also provide process piping connections for custom processing of small quantities of fuel. (auth) 19. Determination of the interfacial heat transfer coefficient in the hot stamping of AA7075 Directory of Open Access Journals (Sweden) Liu Xiaochuan 2015-01-01 Full Text Available The interfacial heat transfer coefficient (IHTC is a key parameter in hot stamping processes, in which a hot blank is formed and quenched by cold dies simultaneously. The IHTC should therefore be identified and used in FE models to improve the accuracy of simulation results of hot stamping processes. In this work, a hot stamping simulator was designed and assembled in a Gleeble 3800 thermo-mechanical testing system and a FE model was built in PAM-STAMP to determine the IHTC value between a hot aluminium alloy 7075 blank and cold dies. The IHTC was determined at different contact pressures under both dry and lubricated (Omega-35 conditions. In addition, a model to calculate the IHTC value at different contact pressures and area densities of lubricant was developed for the hot stamping process. 20. Determination of the Interfacial Heat Transfer Coefficient in the Hot Stamping of AA7075 Directory of Open Access Journals (Sweden) Ji Kang 2016-01-01 Full Text Available The interfacial heat transfer coefficient (IHTC is a key parameter in hot stamping processes, in which a hot blank is formed and quenched by cold dies simultaneously. The IHTC should therefore be identified and used in FE simulations to improve the accuracy of simulation results of hot stamping processes. In this work, a hot stamping simulator was designed and assembled in a Gleeble 3800 thermo-mechanical testing system and a FE model was built in PAM-STAMP to determine the IHTC values between a hot aluminium alloy 7075 blank and cold dies. The IHTC values were determined at different contact pressures under both dry and lubricated (Omega-35 conditions. In addition, a model to calculate the IHTC value at different contact pressures and area densities of lubricant was developed for the hot stamping process, which was proved to be working well with verification tests. 1. High pressure processing reaches the U.S. market International Nuclear Information System (INIS) Mermelstein, N.H. 1997-01-01 The first food product commercially produced by a U.S. company using high-pressure processing has had successful test market results. High-pressure processing permits food to be preserved by subjecting it to pressures in the range of 60,000-100,000 psi for a short time instead of exposing the food to heat, freezing, chemicals, or irradiation. To produce Classic Guacamole, Avomex of Keller, Texas, uses a batch isostatic press to deactivate the enzymes in the avocado and to kill bacteria, obtaining a refrigerated shelf life of over 30 days. The guacamole is then vacuum packed and processed again. The product undergoes no heat treatment and does not contain preservatives, and the high pressure does not affect its texture, color, or taste. Meanwhile, a continuous system for high-pressure processing of pumpable foods is currently being developed by Flow International of Kent, Washington, and will be used for testing and applications work at Oregon State University 2. Fabrication and properties of hot pressed bismuth tungstate International Nuclear Information System (INIS) Streicher, W.L. 1978-01-01 Bi 2 WO 6 is a synthetic polar material that is a possible candidate for energy conversion and detection systems. Previous research on this material has been concerned with crystal growth and sintering characteristics of polycrystalline compacts. This study involves itself with the fabrication of polycrystalline compacts by hot pressing techniques. Densities approaching theoretical crystal density were achieved by hot pressing at 850 0 C for one hour with pressures exceeding 35 MPa. Before hot pressing, the sintering range was determined by high temperature dilatometry of unfired Bi 2 WO 6 ceramics. Hot pressed discs were characterized by scanning electron microscopy, differential scanning calorimetry, and x-ray diffraction. Electrical properties were determined by dc resistivity, capacitance, and conductance measurements, ac poling, dc poling, and current-voltage measurements 3. Residential solar hot water Energy Technology Data Exchange (ETDEWEB) 1982-06-01 This report examines the feasibility of using solar energy to preheat domestic water coming from the city supply at a temperature of approximately 4{degree}C. Four solar collectors totalling 7 m{sup 2} were installed on a support structure facing south at an angle of 60{degree} from the horizontal. The system worked most efficiently in the spring and early summer when the combination of long hours of sunshine, clean air and clear skies allowed for maximum availability of solar radiation. Performance dropped in late summer and fall mainly due to cloudier weather conditions. The average temperature in the storage tank over the 10 months of operation was 42{degree}C, ranging from a high of 83{degree}C in July to a low of 6{degree}C in November. The system provided a total of 7.1 GJ, which is approximately one-third the annual requirement for domestic hot water heating. At the present time domestic use of solar energy to heat water does not appear to be economically viable. High capital costs are the main problem. As a solar system with present day technology can only be expected to meet half to two-thirds of the hot water energy demand the savings are not sufficient for the system to pay for itself within a few years. 5 figs. 4. New isostatic mounting concept for a space born Three Mirror Anastigmat (TMA) on the Meteosat Third Generation Infrared Sounder Instrument (MTG-IRS) Science.gov (United States) Freudling, Maximilian; Klammer, Jesko; Lousberg, Gregory; Schumacher, Jean-Marc; Körner, Christian 2016-07-01 A novel isostatic mounting concept for a space born TMA of the Meteosat Third Generation Infrared Sounder is presented. The telescope is based on a light-weight all-aluminium design. The mounting concept accommodates the telescope onto a Carbon-Fiber-Reinforced Polymer (CRFP) structure. This design copes with the high CTE mismatch without introducing high stresses into the telescope structure. Furthermore a Line of Sight stability of a few microrads under geostationary orbit conditions is provided. The design operates with full performance at a temperature 20K below the temperature of the CFRP structure and 20K below the integration temperature. The mounting will sustain launch loads of 47g. This paper will provide the design of the Back Telescope Assembly (BTA) isostatic mounting and will summarise the consolidated technical baseline reached following a successful Preliminary Design Review (PDR). 5. Hot helium flow test facility summary report International Nuclear Information System (INIS) 1980-06-01 This report summarizes the results of a study conducted to assess the feasibility and cost of modifying an existing circulator test facility (CTF) at General Atomic Company (GA). The CTF originally was built to test the Delmarva Power and Light Co. steam-driven circulator. This circulator, as modified, could provide a source of hot, pressurized helium for high-temperature gas-cooled reactor (HTGR) and gas-cooled fast breeder reactor (GCFR) component testing. To achieve this purpose, a high-temperature impeller would be installed on the existing machine. The projected range of tests which could be conducted for the project is also presented, along with corresponding cost considerations 6. EDF requirements for hot cells examinations on irradiated fuel International Nuclear Information System (INIS) Segura, J.C.; Ducros, G. 2002-01-01 The objectives of increasing French Nuclear Power Plants (NPP) availability while lengthening the fuel irradiation cycle and reaching higher burnups lead EDF to carry out on site and hot cell examinations. The data issued from such fuel behaviour monitoring programmes will be used to ascertain that the design criteria are met. Data are also needed for modelling, development and validation. The paper deals quickly with the logistics linked to the selection and transport of fuel rods from NPP to hot cell laboratory. Hot cell PIEs remain a valuable method to obtain data in such fields as PCI (Pellet-Cladding Interaction), internal pressure, FGR (Fission Gas Release), oxide thickness, metallurgical aspects. The paper introduces burnup determination methods, inner pressure evaluation, preparation of samples for further irradiation such as power ramps for PCI and RIA (Reactivity Initiated Accident) testing. The nuclear microprobe of Perre Suee laboratory is also presented. (author) 7. Hot springs in Hokuriku District Energy Technology Data Exchange (ETDEWEB) Sato, K. (Hot Springs Research Center, Japan) 1971-01-01 In the Hokuriku district including Toyama, Ishikawa, and Fukui Prefectures, hot springs of more than 25/sup 0/C were investigated. In the Toyama Prefecture, there are 14 hot springs which are located in an area from the Kurobe River to the Tateyama volcano and in the mountainous area in the southwest. In Ishikawa Prefecture there are 16 hot springs scattered in Hakusan and its vicinity, the Kaga mountains, and in the Noto peninsula. In northern Fukui Prefecture there are seven hot springs. The hot springs in Shirakawa in Gifu Prefecture are characterized as acid springs producing exhalations and H/sub 2/S. These are attributed to the Quaternary volcanoes. The hot springs of Wakura, Katayamazu, and Awara in Ishikawa Prefecture are characterized by a high Cl content which is related to Tertiary andesite. The hot springs of Daishoji, Yamanaka, Yamashiro, Kuritsu, Tatsunokuchi, Yuwaku, and Yunotani are characterized by a low HCO/sub 3/ content. The Ca and SO/sub 4/ content decreases from east to west, and the Na and Cl content increases from west to east. These fluctuations are related to the Tertiary tuff and rhyolite. The hot springs of Kuronagi, Kinshu, and Babadani, located along the Kurobe River are characterized by low levels of dissolved components and high CO/sub 2/ and HCO/sub 3/ content. These trends are related to late Paleozoic granite. Hot springs resources are considered to be connected to geothermal resources. Ten tables, graphs, and maps are provided. 8. Multifunctional Hot Structure Heat Shield Data.gov (United States) National Aeronautics and Space Administration — This project is performing preliminary development of a Multifunctional Hot Structure (HOST) heat shield for planetary entry. Results of this development will... 9. Ballooning test equipment for use in hot cells International Nuclear Information System (INIS) Broendsted, P.; Adrian, F. 1979-12-01 An equipment for testing the LOCA behaviour of irradiated cladding materials is described. The details of the construction and of the installation in the Hot Cells are reported. Pilot tests carried out showed that the performance of the system fulfills the basic experimental prerequisites, which were: heating rate of 2-3degC/s, final temperature 1150degC/s, internal pressure max. 30 atm, external pressure max. 1 atm, test atmosphere either air or steam. (author) 10. The role of the 2008 Mw 7.9 Wenchuan earthquake in topographic evolution: seismically induced landslides and the associated isostatic response Science.gov (United States) Ren, Z.; Zhang, Z.; Zhang, H.; Zheng, W.; Zhang, P. Z. 2017-12-01 The widely held understanding that reverse-faulting earthquakes play an important role in building mountains has been challenged by recent studies suggesting that co-seismic landslides of the 2008 Mw 7.9 Wenchuan earthquake led to a net co-seismic lowering of surface height. We use precise estimates of co-seismic landslide volumes to calculate the long-term isostatic response to landsliding during the 2008 Wenchuan earthquake. The total isostatic respond volume is 2.0 km3 which did not change much associated with thickness of Te, however, the distribution of the rebound changes associated with thickness of Te. The total co-seismic mass change could be 1.8 km3. The maximum isostatic response due to Wenchuan earthquake may have been as high as 0.9 meters in the highest Pengguan massif of the central Longmen Shan. We also find that the average net uplift is 0.16 meters within the total landslide region due to the Wenchuan earthquake. Our findings suggest that the local topographic evolution of the middle Longmen Shan region is closely related to repeated tectonic events such as the 2008 Wenchuan Earthquake. 11. Fabrication of Y-TZP For Dental Crowns Applications by Combining Slip Casting and Cold Isostatic Pressing International Nuclear Information System (INIS) Hao, C.C.; Andanastuti Muchtar; Che Husna Azhari; Masfueh Razali; Mohamed Aboras 2016-01-01 Yttria-stabilized tetragonal zirconia polycrystalline (Y-TZP) is a popular material for dental restoration because of its outstanding mechanical properties and biocompatibility. Cold isostatic pressing (CIP) and slip casting are among several consolidation methods for Y-TZP. These methods produce Y-TZP with high mechanical properties. This study aims to enhance the mechanical properties of Y-TZP by combining slip casting and CIP. Y-TZP samples were fabricated using CIP, slip casting, and their combination. Subsequently, the green bodies of the samples were sintered at 1600 degree Celcius. Their mechanical properties (density and hardness) were tested and their microstructures were scrutinized under a scanning electron microscope. Compared with the other two methods, the combined method significantly improved the mechanical properties of Y-TZP. In addition, the combined method also produced a compact and homogeneous microstructure. Therefore, the combination of slip casting and CIP is recommended in the production of Y-TZP with high mechanical properties for dental crown applications. (author) 12. Motel solar-hot-water system with nonpressurized storage--Jacksonville, Florida Science.gov (United States) 1981-01-01 Modular roof-mounted copper-plated arrays collect solar energy; heated water drains from them into 1,000 gallon nonpressurized storage tank which supplies energy to existing pressurized motel hot water lines. System provides 65 percent of hot water demand. Report described systems parts and operation, maintenance, and performance and provides warranty information. 13. Low resistance polycrystalline diamond thin films deposited by hot ... Indian Academy of Sciences (India) Administrator silicon wafers using a hydrocarbon gas (CH4) highly diluted with H2 at low pressure in a hot filament chemi- cal vapour ... the laser spot was focused on the sample surface using a ... tative spectra of diamond thin films with a typical dia-. 14. Hot Gas Halos in Galaxies Science.gov (United States) Mulchaey, John Most galaxy formation models predict that massive low-redshift disk galaxies are embedded in extended hot halos of externally accreted gas. Such gas appears necessary to maintain ongoing star formation in isolated spirals like the Milky Way. To explain the large population of red galaxies in rich groups and clusters, most galaxy evolution models assume that these hot gas halos are stripped completely when a galaxy enters a denser environment. This simple model has been remarkably successful at reproducing many observed properties of galaxies. Although theoretical arguments suggest hot gas halos are an important component in galaxies, we know very little about this gas from an observational standpoint. In fact, previous observations have failed to detect soft X-ray emission from such halos in disk galaxies. Furthermore, the assumption that hot gas halos are stripped completely when a galaxy enters a group or cluster has not been verified. We propose to combine proprietary and archival XMM-Newton observations of galaxies in the field, groups and clusters to study how hot gas halos are impacted by environment. Our proposed program has three components: 1) The deepest search to date for a hot gas halo in a quiescent spiral galaxy. A detection will confirm a basic tenet of disk galaxy formation models, whereas a non-detection will seriously challenge these models and impose new constraints on the growth mode and feedback history of disk galaxies. 2) A detailed study of the hot gas halos properties of field early-type galaxies. As environmental processes such as stripping are not expected to be important in the field, a study of hot gas halos in this environment will allow us to better understand how feedback and other internal processes impact hot gas halos. 3) A study of hot gas halos in the outskirts of groups and clusters. By comparing observations with our suite of simulations we can begin to understand what role the stripping of hot gas halos plays in galaxy 15. Hot cell verification facility update International Nuclear Information System (INIS) Titzler, P.A.; Moffett, S.D.; Lerch, R.E. 1985-01-01 The Hot Cell Verification Facility (HCVF) provides a prototypic hot cell mockup to check equipment for functional and remote operation, and provides actual hands-on training for operators. The facility arrangement is flexible and assists in solving potential problems in a nonradioactive environment. HCVF has been in operation for six years, and the facility is a part of the Hanford Engineering Development Laboratory 16. Operation of the hot test loop facilities International Nuclear Information System (INIS) Cheong, Moon Ki; Park, Choon Kyeong; Won, Soon Yeon; Yang, Sun Kyu; Cheong, Jang Whan; Cheon, Se Young; Song, Chul Hwa; Jeon, Hyeong Kil; Chang, Suk Kyu; Jeong, Heung Jun; Cho, Young Ro; Kim, Bok Duk; Min, Kyeong Ho 1994-12-01 The objective of this project is to obtain the available experimental data and to develop the measuring techniques through taking full advantage of the facilities. The facilities operated by the thermal hydraulics department have been maintained and repaired in order to carry out the thermal hydraulics tests necessary for providing the available data. The performance tests for double grid type bottom end piece which was improved on the debris filtering effectivity were performed using the PWR-Hot Test Loop. The CANDU-Hot Test Loop was operated to carry out the pressure drop tests and strength tests of fuel. The Cold Test Loop was used to obtain the local velocity data in subchannel within fuel bundle and to understand the characteristic of pressure drop required for improving the nuclear fuel and to develop the advanced measuring techniques. RCS Loop, which is used to measure the CHF, is presently under design and construction. B and C Loop is designed and constructed to assess the automatic depressurization safety system behavior. 4 tabs., 79 figs., 7 refs. (Author) .new 17. WAVE PROPAGATION in the HOT DUCT of VHTR Energy Technology Data Exchange (ETDEWEB) Richard Schultz; Jim C. P. Liou 2013-07-01 In VHTR, helium from the reactor vessel is conveyed to a power conversion unit through a hot duct. In a hypothesized Depressurized Conduction Cooldown event where a rupture of the hot duct occurs, pressure waves will be initiated and reverberate in the hot duct. A numerical model is developed to quantify the transients and the helium mass flux through the rupture for such events. The flow path of the helium forms a closed loop but only the hot duct is modeled in this study. The lower plum of the reactor vessel and the steam generator are treated as specified pressure and/or temperature boundary to the hot duct. The model is based on the conservation principles of mass, momentum and energy, and on the equations of state for helium. The numerical solution is based on the method of characteristics with specified time intervals with a predictor and corrector algorithm. The rupture sub-model gives reasonable results. Transients induced by ruptures with break area equaling 20%, 10%, and 5% of the duct cross-sectional area are described. 18. Upgrading of biomass by carbonization in hot compressed water Directory of Open Access Journals (Sweden) Wiwut Tanthapanichakoon 2006-09-01 Full Text Available Carbonization of biomass (corn cob in hot compressed water was performed using a small bomb reactor at temperature 300-350ºC and pressure 10-18 MPa for 30 min. Then, the solid product or biochar was subjected to various analyses in order to investigate the effects of the carbonization in hot compressed water on the characteristics of the biochar. It was found that the yield of biochar carbonized in hot compressed water at 350ºC and pressure of 10 MPa for 30 min was 44.7%, whereas the yield of biochar carbonized in nitrogen atmosphere at 350ºC is 36.4%. Based on the information obtained from the elemental analyses of the biochar, it was found that the oxygen functional groups in the corn cob were selectively decomposed during the carbonization in hot compressed water. The pyrolysis and combustion behaviors of the biochar were found to be affected significantly by the carbonization in hot compressed water. 19. Analysis of hot leg natural circulation under station blackout severe accident International Nuclear Information System (INIS) Deng Jian; Cao Xuewu 2007-01-01 Under severe accidents, natural circulation flows are important to influence the accident progression and result in a pressurized water reactor (PWR). In a station blackout accident with no recovery of steam generator (SG) auxiliary feedwater (TMLB' severe accident scenario), the hot leg countercurrent natural circulation flow is analyzed by using a severe-accident code, to better understand its potential impacts on the creep-rupture timing among the surge line, the hot leg; and SG tubes. The results show that the natural circulation may delay the failure time of the hot leg. The recirculation ratio and the hot mixing factor are also calculated and discussed. (authors) 20. Thermal performance test of the hot gas ducts of HENDEL International Nuclear Information System (INIS) Hishida, M.; Kunitomi, K.; Ioka, I.; Umenishi, K.; Tanaka, T.; Shimomura, H.; Sanokawa, K. 1984-01-01 A hot gas duct provided with internal thermal insulation is to be used for high-temperature gas-cooled reactors (HTGR). This type of hot gas duct has not been used so far in industrial facilities, and only a couple of tests on such a large-scale model of a hot gas duct have been conducted. The present report deals with the results of the thermal performance of the single tube type hot gas ducts which are installed as parts of a helium engineering demonstration loop (HENDEL). Uniform temperature and heat flux distribution at the surface of the duct were observed, the experimental correlations being obtained for the effective thermal conductivity of the internal thermal insulation layer. The measured temperature distribution of the pressure tube was in good agreement with the calculation by a TRUMP heat transfer computer code. The temperature distribution of the inner tube of the co-axial hot gas duct was evaluated and no hot spot was detected. These results would be very valuable for the design and development of HTGR. (orig.) 1. Review of Bothnian Sea shore-level displacement data and use of a GIS tool to estimate isostatic uplift International Nuclear Information System (INIS) Vuorela, A.; Penttinen, T.; Lahdenperae, A.-M. 2009-02-01 The aim and approach of the study were to produce source data estimates necessary for modelling the future biosphere. The study updated the list of 14 C datings of sea-level index points, which show when lakes and mires were isolated from the Baltic Sea due to isostatic uplift. The study concentrated on the Bothnian Sea, especially the Olkiluoto area. The older Finnish datings (a list of 260 sea-level index points determined in 1995) were checked and revised as needed. New data was available for 56 Finnish and 41 Swedish index points. State-of-the-art 14 C calibration methods were applied. Various available data were used to estimate the parameters of the glacio-isostatic uplift model's slow component. The component describes the uplift in relation to time using parameters B s , which is related to the uplift's total duration, and A s , which is half of the total uplift possible in the period lasting from the Last Glacial Maximum to the distant future. The B s values were estimated by means of 1) crustal thickness and 2) shoreline displacement curves. In applying method 1, this study revised the function describing the relationship between crustal thickness and B s and created a new derivative-based method that also estimates the parameter A s without radiocarbon datings and using only crustal thickness and current uplift maps. In method 2, sea-level index point subsets along the Finnish and Swedish coasts of the Bothnian Sea were selected from the revised database, and their datings and elevations were used to determine the corresponding land uplift parameters. The parameter value distributions were used to produce maps. The values of the inertia factor B s are on average 6% higher than those calculated in 2001 but they are 10% lower in the Olkiluoto region. According to the interpolations of the new and old data, the estimated uplift at Olkiluoto for AD 12000 is 2.8 m (7%) less than calculated previously. The derivative-based method predicts an uplift for AD 2. Hot testing of coke Energy Technology Data Exchange (ETDEWEB) Balon, I D 1976-07-01 Earlier investigations failed to take full account of the factors affecting coke behavior within the blast furnace. An apparatus was accordingly developed for testing coke, based on a cyclone furnace where the sample could be held in a flow of hot oxidizing gases, simulating conditions in the blast furnace hearth. The results are said to be suitable for comprehensive assessment of the coke, including abrasive strength and its rate of gasification in a flow of carbon dioxide. Coke of size 6-10 mm tested at 1,100/sup 0/C in an atmosphere of oxidizing gases close to those obtaining in the blast furnace hearth, indicated that destruction and total gasification of the coke occurs after 5 minutes for a weak coke and 8 minutes for strong coke, depending on the physico-chemical and physico-mechanical properties of the particular coke. When samples were treated for a fixed period (3 minutes), the amount of coke remaining, and the percentage over 6 mm varied between 22 and 40 and between 4 and 7 percent respectively. 3. Hot Hydrogen Test Facility International Nuclear Information System (INIS) W. David Swank 2007-01-01 The core in a nuclear thermal rocket will operate at high temperatures and in hydrogen. One of the important parameters in evaluating the performance of a nuclear thermal rocket is specific impulse, ISp. This quantity is proportional to the square root of the propellant's absolute temperature and inversely proportional to square root of its molecular weight. Therefore, high temperature hydrogen is a favored propellant of nuclear thermal rocket designers. Previous work has shown that one of the life-limiting phenomena for thermal rocket nuclear cores is mass loss of fuel to flowing hydrogen at high temperatures. The hot hydrogen test facility located at the Idaho National Lab (INL) is designed to test suitability of different core materials in 2500 C hydrogen flowing at 1500 liters per minute. The facility is intended to test non-uranium containing materials and therefore is particularly suited for testing potential cladding and coating materials. In this first installment the facility is described. Automated Data acquisition, flow and temperature control, vessel compatibility with various core geometries and overall capabilities are discussed 4. A Comparison of the Crustal Deformation Predicted by Glacial Isostatic Adjustment to Seismicity in the Baffin Region of Northern Canada Science.gov (United States) James, T. S.; Schamehorn, T.; Bent, A. L.; Allen, T. I.; Mulder, T.; Simon, K. 2016-12-01 The horizontal crustal strain-rates induced by glacial isostatic adjustment (GIA) in northern Canada and western Greenland region are compared to the spatial pattern of seismicity. For the comparison, an updated seismicity catalogue was created from the 2010 version of the NRCan Seismic Hazard Earthquake Epicentre File (SHEEF2010) catalogue and the Greenland Ice Sheet Monitoring Network (GLISN) catalogue of the Geological Survey of Denmark and Greenland (GEUS). Crustal motion rates were computed with the Innu/Laur16 ice-sheet history and the VM5a viscosity profile (Simon et al., 2015; 2016). This GIA model optimizes the fit to relative sea-level and vertical crustal motion measurements around Hudson Bay and in the Canadian Arctic Archipelago (CAA). A region in Baffin Bay with historically high seismicity, including the 1933 M 7.4 and the 1934 and 1945 M 6.5 earthquakes, features high predicted GIA strain-rates. Elsewhere, agreement is not strong, with zones of seismicity occurring where predicted horizontal crustal strain-rates are small and large crustal strain-rates predicted where earthquake occurrence is muted. For example, large compressional crustal strain-rates are predicted beneath seismically quiescent portions of the Greenland ice sheet. Similarly, large predicted extensional strain-rates occur around southern Hudson Bay and the Foxe Basin, which are also regions of relative seismic quiescence. Additional factors to be considered include the orientation of the background stress field, relative to the predicted stress changes, and potential pre-existing zones of lithospheric weakness. 5. Joint inversion estimate of regional glacial isostatic adjustment in Antarctica considering a lateral varying Earth structure (ESA STSE Project REGINA) Science.gov (United States) Sasgen, Ingo; Martín-Español, Alba; Horvath, Alexander; Klemann, Volker; Petrie, Elizabeth J.; Wouters, Bert; Horwath, Martin; Pail, Roland; Bamber, Jonathan L.; Clarke, Peter J.; Konrad, Hannes; Drinkwater, Mark R. 2017-12-01 A major uncertainty in determining the mass balance of the Antarctic ice sheet from measurements of satellite gravimetry, and to a lesser extent satellite altimetry, is the poorly known correction for the ongoing deformation of the solid Earth caused by glacial isostatic adjustment (GIA). Although much progress has been made in consistently modeling the ice-sheet evolution throughout the last glacial cycle, as well as the induced bedrock deformation caused by these load changes, forward models of GIA remain ambiguous due to the lack of observational constraints on the ice sheet's past extent and thickness and mantle rheology beneath the continent. As an alternative to forward-modeling GIA, we estimate GIA from multiple space-geodetic observations: Gravity Recovery and Climate Experiment (GRACE), Envisat/ICESat and Global Positioning System (GPS). Making use of the different sensitivities of the respective satellite observations to current and past surface-mass (ice mass) change and solid Earth processes, we estimate GIA based on viscoelastic response functions to disc load forcing. We calculate and distribute the viscoelastic response functions according to estimates of the variability of lithosphere thickness and mantle viscosity in Antarctica. We compare our GIA estimate with published GIA corrections and evaluate its impact in determining the ice-mass balance in Antarctica from GRACE and satellite altimetry. Particular focus is applied to the Amundsen Sea Sector in West Antarctica, where uplift rates of several centimetres per year have been measured by GPS. We show that most of this uplift is caused by the rapid viscoelastic response to recent ice-load changes, enabled by the presence of a low-viscosity upper mantle in West Antarctica. This paper presents the second and final contributions summarizing the work carried out within a European Space Agency funded study, REGINA (www.regina-science.eu). 6. NORTH PORTAL - HOT WATER CALCULATION - CHANGE HOUSE FACILITY NO.5008 International Nuclear Information System (INIS) Blackstone, R. 1996-01-01 The purpose of this design analysis and calculation is to determine the demand for hot water and to size the supply main piping for the Change House Facility No.5008 in accordance with the Uniform Plumbing Code (UPC) (Section 4.4.1) and U.S. Department of Energy Order 6430.1A-1540. The method used for the calculations is based on Section 4.4.1. The first step is to determine the maximum pressure drop between the most remote plumbing fixture and the main supply. The pressure drop for the hot water system is based on the total length of the supply piping from the cold water supply source through the water heater to the most remote hot water outlet. Equivalent fixture units are then assigned using Section 4.4.1. For hot water, the values are reduced by 25 percent in accordance with the UPC. The demand load in gpm is then determined based on the number of fixture units. The demand load and the pressure drop between the source and the most remote fixture is used to determine the pipe size and the corresponding friction losses for a given flow velocity not to exceed 10 feet/second 7. Biomass gasification hot gas cleanup for power generation Energy Technology Data Exchange (ETDEWEB) Wiant, B.C.; Bachovchin, D.M. [Westinghouse Electric Corp., Orlando, FL (United States); Carty, R.H.; Onischak, M. [Institute of Gas Technology, Chicago, IL (United States); Horazak, D.A. [Gilbert/Commonwealth, Reading, PA (United States); Ruel, R.H. [The Pacific International Center for High Technology Research, Honolulu, HI (United States) 1993-12-31 In support of the US Department of Energys Biomass Power Program, a Westinghouse Electric led team consisting of the Institute of Gas Technology (IGT), Gilbert/Commonwealth (G/C), and the Pacific International Center for High Technology Research (PICHTR), is conducting a 30 month research and development program. The program will provide validation of hot gas cleanup technology with a pressurized fluidized bed, air-blown, biomass gasifier for operation of a gas turbine. This paper discusses the gasification and hot gas cleanup processes, scope of work and approach, and the program`s status. 8. Curvature-driven instabilities in a hot-electron plasma: radial analysis International Nuclear Information System (INIS) Berk, H.L.; Van Dam, J.W.; Rosenbluth, M.N.; Spong, D.A. 1981-12-01 The theory of unfavorable curvature-driven instabilities is developed for a plasma interacting with a hot electron ring whose drift frequencies are larger than the growth rates predicted from conventional magnetohydrodynamic theory. A z-pinch model is used to emphasize the radial structure of the problem. Stability criteria are obtained for the five possible modes of instability: the conventional hot electron interchange, a high-frequency hot electron interchange (at frequencies larger than the ion cyclotron frequency), a compressional instability, a background pressure-driven interchange, and an interacting pressure-driven interchange 9. Manufacturing of small scale W monoblock mockups by hot radial pressing International Nuclear Information System (INIS) Visca, Eliseo; Testani, C.; Libera, S.; Sacchetti, M. 2003-01-01 In the frame of the European Technology R and D programme for International thermonuclear experimental reactor (ITER) and in the area of high heat flux plasma facing components (HHFC), representative small-scale mock-ups were manufactured and tested to compare different concepts and joining technologies (i.e. active brazing, hot isostatic pressing (HIPping), diffusion bonding, etc.). On the basis of the results obtained by thermal fatigue tests, the monoblock concept resulted to be the most robust one, particularly when the HIPping manufacturing technology is used. Within this programme, ENEA developed an alternative technique for manufacturing plasma-facing components with a monoblock geometry of the ITER machine. The basic idea of this technique, named hot radial pressing (HRP), is to perform a radial diffusion bonding between the cooling tube and the armour tile by pressurising the internal tube only and by keeping the process parameters within the range in which the thermo-mechanical properties of the copper alloys are not yet degraded. The HRP is performed by a standard furnace, in which only a section of the canister is heated. The manufacturing procedure and the results of the screening and fatigue thermal tests performed on the ENEA mock-ups are reported in this paper 10. HOT STARS WITH HOT JUPITERS HAVE HIGH OBLIQUITIES International Nuclear Information System (INIS) Winn, Joshua N.; Albrecht, Simon; Fabrycky, Daniel; Johnson, John Asher 2010-01-01 We show that stars with transiting planets for which the stellar obliquity is large are preferentially hot (T eff > 6250 K). This could explain why small obliquities were observed in the earliest measurements, which focused on relatively cool stars drawn from Doppler surveys, as opposed to hotter stars that emerged more recently from transit surveys. The observed trend could be due to differences in planet formation and migration around stars of varying mass. Alternatively, we speculate that hot-Jupiter systems begin with a wide range of obliquities, but the photospheres of cool stars realign with the orbits due to tidal dissipation in their convective zones, while hot stars cannot realign because of their thinner convective zones. This in turn would suggest that hot Jupiters originate from few-body gravitational dynamics and that disk migration plays at most a supporting role. 11. Hot workability of aluminium alloys International Nuclear Information System (INIS) Yoo, Yeon Chul; Oh, Kyung Jin 1986-01-01 Hot Workability of aluminium alloys, 2024, 6061 and 7075, has been studied by hot torsion tests at temperatures from 320 to 515 deg C and at strain rates from 1.26 x 10 -3 to 5.71 x 10 -3 sec -1 . Hot working condition of these aluminium alloys was determined quantitatively from the constitutive equations obtained from flow stress curves in torsion. Experimental data of the logarith of the Zener-Hollomonn parameter showed good linear relationships to the logarith of sinh(ασ-bar) 12. Hot pressing of B{sub 4}C/SiC composites Energy Technology Data Exchange (ETDEWEB) Sahin, F.C.; Turhan, E.; Yesilcubuk, S.A.; Addemir, O. [Ystanbul Technical University, Faculty of Chemistry and Metallurgy, Materials and Metallurgical Engineering Dept., Maslak-Ystanbul (Turkey) 2005-07-01 B{sub 4}C/SiC ceramic composites containing 10-20-30 vol % SiC were prepared by hot pressing method. The effect of SiC addition and hot pressing temperature on sintering behaviour and mechanical properties of hot pressed composites were investigated. Microstructures of hot pressed samples were examined by SEM technique. Three different temperatures (2100 deg. C, 2200 deg. C and 2250 deg. C) were used to optimize hot pressing temperature applying 100 MPa pressure under argon atmosphere during the sintering procedure. The highest relative density of 98.44 % was obtained by hot pressing at 2250 deg. C. However, bending strengths of B{sub 4}C/SiC composite samples were lower than monolithic B{sub 4}C in all experimental conditions. (authors) 13. Cooling it gets hot. Science.gov (United States) Weber, D O 1999-01-01 Conflict is an inevitable part of work and relationships. How it is handled determines what can and cannot be accomplished personally, professionally, and organizationally. The pressures and complexities of health care interactions breeds conflicts that require constant, skillful negotiation. Increasingly, health care leaders are recognizing that proficiency at recognizing sources of friction before trouble flares up and at managing and resolving disputes that do break out is an essential part of their executive "toolbox." Resources are now widely available for acquiring fundamental knowledge of dispute prevention and negotiation techniques, and for locating and engaging reliable expertise when third-party intervention appears necessarily to reconcile apparently intractable differences. 14. Catalytic hot gas cleaning Energy Technology Data Exchange (ETDEWEB) Simell, P [VTT Energy, Espoo (Finland) 1997-12-31 Gasification gas that contains particulates can be purified from tars and ammonia by using nickel monolith catalysts. Temperatures over 900 deg C are required at 20 bar pressure to avoid deactivation by H{sub 2}S and carbon. Dolomites and limestones are effective tar decomposing catalysts only when calcined. Tar decomposition in gasification conditions can take place by steam or dry (CO{sub 2}) reforming reactions. These reactions follow apparent first order kinetics with respect to hydrocarbons in gasification conditions. (author) (16 refs.) 15. Catalytic hot gas cleaning Energy Technology Data Exchange (ETDEWEB) Simell, P. [VTT Energy, Espoo (Finland) 1996-12-31 Gasification gas that contains particulates can be purified from tars and ammonia by using nickel monolith catalysts. Temperatures over 900 deg C are required at 20 bar pressure to avoid deactivation by H{sub 2}S and carbon. Dolomites and limestones are effective tar decomposing catalysts only when calcined. Tar decomposition in gasification conditions can take place by steam or dry (CO{sub 2}) reforming reactions. These reactions follow apparent first order kinetics with respect to hydrocarbons in gasification conditions. (author) (16 refs.) 16. Hot Hydrogen Heat Source Development Data.gov (United States) National Aeronautics and Space Administration — The purpose of this project is to develop a hot hydrogen heat source that would produce a high temperature hydrogen flow which would be comparable to that produced... 17. The decay of hot nuclei International Nuclear Information System (INIS) Moretto, L.G.; Wozniak, G.J. 1988-11-01 The formation of hot compound nuclei in intermediate-energy heavy ion reactions is discussed. The statistical decay of such compound nuclei is responsible for the abundant emission of complex fragments and high energy gamma rays. 43 refs., 23 figs 18. Mercury content in Hot Springs Energy Technology Data Exchange (ETDEWEB) Nakagawa, R 1974-01-01 A method of determination of mercury in hot spring waters by flameless atomic absorption spectrophotometry is described. Further, the mercury content and the chemical behavior of the elementary mercury in hot springs are described. Sulfide and iodide ions interfered with the determination of mercury by the reduction-vapor phase technique. These interferences could, however, be minimized by the addition of potassium permanganate. Waters collected from 55 hot springs were found to contain up to 26.0 ppb mercury. High concentrations of mercury have been found in waters from Shimoburo Springs, Aomori (10.0 ppb), Osorezan Springs, Aomori (1.3 approximately 18.8 ppb), Gosyogake Springs, Akita (26.0 ppb), Manza Springs, Gunma (0.30 approximately 19.5 ppb) and Kusatu Springs, Gunma (1.70 approximately 4.50 ppb). These hot springs were acid waters containing a relatively high quantity of chloride or sulfate. 19. Do scientists trace hot topics? Science.gov (United States) Wei, Tian; Li, Menghui; Wu, Chensheng; Yan, Xiao-Yong; Fan, Ying; Di, Zengru; Wu, Jinshan 2013-01-01 Do scientists follow hot topics in their scientific investigations? In this paper, by performing analysis to papers published in the American Physical Society (APS) Physical Review journals, it is found that papers are more likely to be attracted by hot fields, where the hotness of a field is measured by the number of papers belonging to the field. This indicates that scientists generally do follow hot topics. However, there are qualitative differences among scientists from various countries, among research works regarding different number of authors, different number of affiliations and different number of references. These observations could be valuable for policy makers when deciding research funding and also for individual researchers when searching for scientific projects. 20. Moho geometry gravity inversion experiment (MoGGIE): A refined model of the Australian Moho, and its tectonic and isostatic implications Science.gov (United States) Aitken, Alan R. A. 2010-08-01 At the continent-scale, models of Moho depth based on seismic estimates alone can be inadequate due to irregular or sparse data. Gravity-based Moho modelling provides better coverage, however, the methods used are typically hampered by an inability to explicitly honour seismic constraints and are also limited by over simplistic model conditions, e.g. laterally-homogenous layering. I present a new method to generate a continent-scale Moho model, based on the constrained inversion of free-air gravity data. This method explicitly honours seismic Moho estimates and accounts for a laterally heterogeneous crust and mantle. Resolution and sensitivity testing shows that, for wavelengths greater than 200 km, crustal density and Moho depth are recovered with reasonable accuracy, ± 30 kg m - 3 and ± 3 km respectively. MoGGIE uses a six layer model incorporating ocean, sedimentary basin, upper crust, lower/oceanic crust, eclogitised crust and mantle. Inversion variables were the density of the crustal layers, constrained by a standard density model, and the depths to intra-crustal boundaries and the Moho, constrained by 230 seismic depth estimates. The results demonstrate that a balanced approach to seismically-constrained gravity inversion has the capability to generate detailed and well-constrained models of the Moho and crustal density at the continent-scale. For Australia, this is a clear improvement on the sparse and irregular resolution of the Moho provided by seismic estimates of crustal thickness, which fail to resolve short-wavelength features. Newly defined tectonic features include extensive magmatic underplates, crustal-scale shear zones, and the boundaries between tectonic blocks. Isostatic analysis reveals that little of the continent is close to isostatic equilibrium, with isostatic disequilibria preserved at multiple scales, from hundreds of kilometres to the entire continent. These disequilibria are interpreted to indicate long-wavelength flexure of highly 1. Evidence for Isostatic Emergence and Holocene Environmental Change Recorded in Chironomid Assemblages and Sediment Composition of Coastal Lake T1 in SW Greenland Science.gov (United States) Berman, K.; Axford, Y.; Lasher, G. E. 2017-12-01 Multi-proxy analysis of a coastal lake in southwest Greenland near Nuuk provides evidence for regional environmental changes, including the timing of isostatic rebound and the temperature history of the area. T1 (informal name) is a small lake 50 km south of Nuuk, at 17.5 m elevation and currently isolated from glacial meltwater drainage. The lake's sediment record begins approximately 9500 cal years BP, when the site was submerged beneath sea level due to glacial isostatic depression following the Last Glacial Maximum. The record captures the transition of the environment from a submerged, glacially-influenced marine site to a non-glacially fed (and initially meromictic) freshwater lake 8600 cal years BP. Magnetic susceptibility, a proxy for sediment minerogenic content, decreased rapidly from 9500 to 8600 years BP, before abruptly stabilizing and remaining relatively low and steady for the rest of the record. The transition to a lacustrine environment was characterized by a rapid and relatively simultaneous increase in primary productivity (inferred from biogenic silica concentrations) and shift towards terrestrial versus marine sources of organic matter (inferred from carbon:nitrogen ratios and nitrogen isotopes) between 8700 and 8400 years BP. Together, these proxies and the presence of marine shells below the transition provide robust evidence for the transition from a marine environment to a freshwater lake in response to regional postglacial isostatic rebound. Within the Holocene, measures of bulk sediment composition (e.g., biogenic silica, loss-on-ignition and magnetic susceptibility) are relatively stable. Chironomid (Insecta: Diptera: Chironomidae) assemblages, which in some environments are quantitative proxies for summer temperature changes, show species-level shifts within the Holocene that will be interpreted in this presentation alongside indicators of landscape change including carbon:nitrogen ratios, bulk sediment spectral reflectance and bulk 2. Relative sea-level changes and glacio-isostatic adjustment on the Magdalen Islands archipelago (Atlantic Canada) from MIS 5 to the late Holocene Science.gov (United States) Rémillard, Audrey M.; St-Onge, Guillaume; Bernatchez, Pascal; Hétu, Bernard; Buylaert, Jan-Pieter; Murray, Andrew S.; Lajeunesse, Patrick 2017-09-01 The Magdalen Islands (Québec, Canada) in the centre of the Gulf of St. Lawrence are located in a strategic position for providing an overview of the relative sea-level (RSL) history of the Maritime Provinces of eastern Canada. Although data are available for the coastal terrestrial areas of the Maritimes, data from the Gulf are very scarce and both the RSL and glacio-isostatic adjustment (GIA) models extrapolate for this central region. This study provides new stratigraphic and chronological data from four outcrops and two coring sites on the Magdalen Islands. In addition to the five samples used mainly for age control purposes, nine new luminescence ages are presented. With these new data added to the available literature, a new RSL curve is reconstructed for the LGM to the late Holocene period and a partial curve is proposed for the interval between the late MIS 4 to the MIS 3. Data also indicate a few insights for the MIS 5 period. Results reveal that for the LGM to the late Holocene, the curve corresponds to the J-shaped curve scenario recognized in the literature. The RSL changes during this period are the result of glacio-isostatic rebound, migration and collapse of the peripheral forebulge, and eustatic sea-level changes. For the LGM to the early Holocene, glacio-isostatic depression curves displaying a few local differences are also proposed. For the late Holocene, the data constrain the curve between two types of indicators, i.e. marine and terrestrial, and indicate that the RSL has risen at least 3 m during the last two millennia. Sediments dated to the MIS 5 and the interval between the late MIS 4 and the MIS 3 illustrate that the GIA following the LGM also occurred for the MIS 5 interglacial and the MIS 3 interstadial. Finally, recent GIA models are discussed in light of the results of this paper. 3. Data on the influence of cold isostatic pre-compaction on mechanical properties of polycrystalline nickel sintered using Spark Plasma Sintering Directory of Open Access Journals (Sweden) Guy-Daniel Dutel 2017-04-01 Full Text Available Data regarding bulk polycrystalline nickel samples obtained by powder metallurgy using Spark Plasma Sintering (SPS are presented, with a special emphasis on the influence of a cold isostatic pre-compaction on the resulting morphologies and subsequent mechanical properties. Three types of initial powders are used, nanometric powders, micrometric powders and a mixture of the formers. For each type of powder, the SPS cycle has been optimized for the powders without pre-compaction and the same cycle has been used to also sinter pre-compacted powders. 4. Uncertainty analysis for hot channel International Nuclear Information System (INIS) Panka, I.; Kereszturi, A. 2006-01-01 The fulfillment of the safety analysis acceptance criteria is usually evaluated by separate hot channel calculations using the results of neutronic or/and thermo hydraulic system calculations. In case of an ATWS event (inadvertent withdrawal of control assembly), according to the analysis, a number of fuel rods are experiencing DNB for a longer time and must be regarded as failed. Their number must be determined for a further evaluation of the radiological consequences. In the deterministic approach, the global power history must be multiplied by different hot channel factors (kx) taking into account the radial power peaking factors for each fuel pin. If DNB occurs it is necessary to perform a few number of hot channel calculations to determine the limiting kx leading just to DNB and fuel failure (the conservative DNBR limit is 1.33). Knowing the pin power distribution from the core design calculation, the number of failed fuel pins can be calculated. The above procedure can be performed by conservative assumptions (e.g. conservative input parameters in the hot channel calculations), as well. In case of hot channel uncertainty analysis, the relevant input parameters (k x, mass flow, inlet temperature of the coolant, pin average burnup, initial gap size, selection of power history influencing the gap conductance value) of hot channel calculations and the DNBR limit are varied considering the respective uncertainties. An uncertainty analysis methodology was elaborated combining the response surface method with the one sided tolerance limit method of Wilks. The results of deterministic and uncertainty hot channel calculations are compared regarding to the number of failed fuel rods, max. temperature of the clad surface and max. temperature of the fuel (Authors) 5. Fort St. Vrain hot functional test results International Nuclear Information System (INIS) Phelps, R.D. 1974-01-01 A description is given of Fort St. Vrain hot functional tests performed to evaluate the initial nonnuclear performance of the primary coolant system and the associated effects on the various internal components of the reactor vessel and primary coolant system. The components included the twelve steam generator modules, the four helium circulators, the PCRV thermal barrier and liner coolant system, the helium purification system, and the primary and secondary closures at each of the PCRV penetrations. Additional objectives included analysis of the parallel operation of the four helium circulators and the performance of several circulator start/stop transients under various conditions of primary coolant temperature and pressure. Vibration and acoustical phenomena within the vessel were measured, recorded, and compared to theoretical analyses; a verification of reverse flow in the shutdown loop steam generator during one loop operation was performed; the PCRV was again observed for its structural response to internal pressure; and comparisons were made relative to data recorded during the initial pressure test completed in July 1971. (U.S.) 6. Statistical hot spot analysis of reactor cores International Nuclear Information System (INIS) Schaefer, H. 1974-05-01 This report is an introduction into statistical hot spot analysis. After the definition of the term 'hot spot' a statistical analysis is outlined. The mathematical method is presented, especially the formula concerning the probability of no hot spots in a reactor core is evaluated. A discussion with the boundary conditions of a statistical hot spot analysis is given (technological limits, nominal situation, uncertainties). The application of the hot spot analysis to the linear power of pellets and the temperature rise in cooling channels is demonstrated with respect to the test zone of KNK II. Basic values, such as probability of no hot spots, hot spot potential, expected hot spot diagram and cumulative distribution function of hot spots, are discussed. It is shown, that the risk of hot channels can be dispersed equally over all subassemblies by an adequate choice of the nominal temperature distribution in the core 7. EDF experience with open-quotes hot spotclose quotes management International Nuclear Information System (INIS) Guio, J.M. de 1995-01-01 During the past few years, open-quotes hot spotsclose quotes due to the presence of particles of metal activated during their migration through the reactor core, have been detected at several French pressurized water reactor (PWR) units. These open-quotes hot spots,close quotes which generate very high dose rates (from about 10 Gy/h to 200 G/h) are a significant factor in increase occupational exposures during outrates. Of particular concern are the difficult cases which prolong outage duration and increase the volume of radiological waste. Confronted with this situation, Electricite de France (EDF) has set up a national research group, as part of its ALARA program, to establish procedures and techniques to avoid, detect, and eliminate of hot spots. In particular, specific processes have been developed to eliminate these hot spots which are most costly in terms of occupational exposure due to the need for reactor maintenance. This paper sets out the general approach adopted at EDF so far to cope with the problem of hot spots, illustrated by experience at Blayais 3 and 4 8. Tribological Behavior of Laser Textured Hot Stamping Dies Directory of Open Access Journals (Sweden) Andre Shihomatsu 2016-01-01 Full Text Available Hot stamping of high strength steels has been continuously developed in the automotive industry to improve mechanical properties and surface quality of stamped components. One of the main challenges faced by researchers and technicians is to improve stamping dies lifetime by reducing the wear caused by high pressures and temperatures present during the process. This paper analyzes the laser texturing of hot stamping dies and discusses how different surfaces textures influence the lubrication and wear mechanisms. To this purpose, experimental tests and numerical simulation were carried out to define the die region to be texturized and to characterize the textured surface topography before and after hot stamping tests with a 3D surface profilometer and scanning electron microscopy. Results showed that laser texturing influences the lubrication at the interface die-hot sheet and improves die lifetime. In this work, the best texture presented dimples with the highest diameter, depth, and spacing, with the surface topography and dimples morphology practically preserved after the hot stamping tests. 9. Research on thermal insulation for hot gas ducts International Nuclear Information System (INIS) Broeckerhoff, P. 1984-01-01 The inner surfaces of prestressed reactor vessels and hot gas ducts of Gas Cooled High Temperature Reactors need internal thermal insulation to protect the pressure bearing walls from high temperatures. The design parameters of the insulation depend on the reactor type. In a PNP-plant temperature and pressure of the cooling medium helium are proposed to be 950 deg. C and 40 bars, respectively. The experimental work was started at KFA in 1971 for the HHT-project using three test facilities. At first metallic foil insulation and stuffed fibre insulating systems, the hot gas ducting shrouds of which were made of metal, have been tested. Because of the elevated helium temperature in case of PNP and the resulting lower strength of the metallic parts the interest was directed to rigid ceramic materials for the spacers and the inner shrouds. This led to modified structures designed by the INTERATOM company. Tests were performed at KFA. The main object of the investigations was to study the influence of temperature, pressure and axial pressure gradients on the thermal efficiency of the structures. Moreover, the temperatures within the insulation, at the pressure tube, and at the elements which bear the inner shrouds were measured. Thermal fluxes and effective thermal conductivities in axial and circumferential direction of the pressure tube are given, mainly for the INTERATOM-design with spherical spacers. (author) 10. Hot pressing and lithification of gouge during the Mount St. Helens 2004-2008 eruption: insights from high temperature deformation experiments Science.gov (United States) Ryan, Amy G.; Russell, James K.; Heap, Michael J. 2017-04-01 and 850°C. This change in axial strain-time curves with increasing T suggests the inclusion of a second densification process, aside from mechanical compaction, at elevated T. It is our hypothesis that solid-state sintering, a process wherein crystalline particles are fused together as a result of atomic diffusion across grain boundaries (i.e., the process occurring during the industrial production of ceramics by hot (isostatic) pressing), is the dominant mechanism operating at high T and under pressure. While viscous sintering (i.e. welding) operates in many "melt-glass-rich" volcanic systems, solid-state sintering has yet to be explored as a densification mechanism operating on fine granular crystalline volcanic materials at conditions and timescales relevant to volcanic processes. 11. Experimental optimization of temperature distribution in the hot-gas duct through the installation of internals in the hot-gas plenum of a high-temperature reactor International Nuclear Information System (INIS) Henssen, J.; Mauersberger, R. 1990-01-01 The flow conditions in the hot-gas plenum and in the adjacent hot-gas ducts and hot-gas pipes for the high-temperature reactor project PNP-1000 (nuclear process heat project for 1000 MW thermal output) have been examined experimentally. The experiments were performed in a closed loop in which the flow model to be analyzed, representing a 60deg sector of the core bottom of the PNP-1000 with connecting hot-gas piping and diverting arrangements, was installed. The model scale was approx. 1:5.6. The temperature and flow velocity distribution in the hot-gas duct was registered by means of 14 dual hot-wire flowmeters. Through structural changes and/or the installation of internals into the hot-gas plenum of the core bottom offering little flow resistance coolant gas temperature differentials produced in the core could be reduced to such an extent that a degree of mixture amounting to over 80% was achieved at the entrance of the connected heat exchanger systems. Thereby the desired goal of an adequate degree of mixture of the hot gas involving an acceptable pressure loss was reached. (orig.) 12. Hot filtration 1 International Nuclear Information System (INIS) Barbieri, R.R.; Krikscikas de Blanco, Elsa; Liberman, S.J. 1982-01-01 The study of graphite filters is a subject of interest since they provide a convenient method for water cleaning at high temperature in nuclear power stations. The contribution of the double layer interaction on the mechanism of magnetite deposition on granular graphite beds was determined by measuring retention efficiencies, differential pressures across the bed and electrophoretic mobilities as a function of pH. At pH 5 a flat maximum in the retention efficiency and a deep minimum in the superficial energy of interaction as a function of pH were obtained. These results show that, even though the double layer interaction is responsible for the changes of the retention efficiency with pH, its contribution does not play an important role on the mechanism of the deposition of the magnetite particles in the graphite bed. It is suggested that the pores' mechanical obstruction effect by particle's aggregation could be a factor of great influence on the retention efficiency. (Author) [es 13. Modelling of hot air chamber designs of a continuous flow grain dryer DEFF Research Database (Denmark) Kjær, Lotte Strange; Poulsen, Mathias; Sørensen, Kim 2018-01-01 The pressure loss, flow distribution and temperature distribution of a number of designs of the hot air chamber in a continuous flow grain dryer, were investigated using CFD. The flow in the dryer was considered as steady state, compressible and turbulent. It is essential that the grain...... is uniformly dried as uneven drying can result in damage to the end-product during storage. The original commercial design was modified with new guide vanes at the inlets to reduce the pressure loss and to ensure a uniform flow to the line burner in the hot air chamber. The new guide vane design resulted...... in a 10% reduction in pressure loss and a γ-value of 0.804. Various design changes of the hot air chamber were analysed in terms of pressure loss and temperature distribution with the aim of a temperature variation of 5 K at the outlet ducts. An obstruction design was analysed, which improved mixing... 14. Hot Jupiters around M dwarfs Directory of Open Access Journals (Sweden) Murgas F. 2013-04-01 Full Text Available The WFCAM Transit Survey (WTS is a near-infrared transit survey running on the United Kingdom Infrared Telescope (UKIRT. We conduct Monte Carlo transit injection and detection simulations for short period (<10 day Jupiter-sized planets to characterize the sensitivity of the survey. We investigate the recovery rate as a function of period and magnitude in 2 hypothetical star-planet cases: M0–2 + hot Jupiter, M2–4 + hot Jupiter. We find that the WTS lightcurves are very sensitive to the presence of Jupiter-sized short-period transiting planets around M dwarfs. The non-detection of a hot-Jupiter around an M dwarf by the WFCAM Transit Survey allows us to place a firm upper limit of 1.9 per cent (at 95 per cent confidence on the planet occurrence rate. 15. Hot-pressing steatite bodies International Nuclear Information System (INIS) Aparicio Arroyo, E. 1967-01-01 Requirements for some special nuclear engineering ceramic shapes are: big size, impervious, dimensional accuracy and good mechanical and dielectric properties. Limitations of te conventional methods and advantages of te hot pressing techniques for the manufacturing of these shapes are discussed. Hot pressing characteristics of a certain steatite powder are studied. Occurrence of an optimum densification temperature just above the tale decomposition range is found. Experimental data show that the height/diameter ratio of the specimen has no effect on the sintering conditions. Increasing darkness from the graphite mould is detected above the optimum temperature. The hot-pressed steatite is compared with a fired dry-pressed sample of the same composition. (Author) 13 refs 16. CO2 Laser Cutting of Hot Stamping Boron Steel Sheets OpenAIRE Pasquale Russo Spena 2017-01-01 This study investigates the quality of CO2 laser cutting of hot stamping boron steel sheets that are employed in the fabrication of automotive body-in-white. For this purpose, experimental laser cutting tests were conducted on 1.2 mm sheets at varying levels of laser power, cutting speed, and oxygen pressure. The resulting quality of cut edges was evaluated in terms of perpendicularity tolerance, surface irregularity, kerf width, heat affected zone, and dross extension. Experimental tests wer... 17. Electron microscopy characterization of mechanically alloyed and hot consolidates Cu-Cr3C2 particles Directory of Open Access Journals (Sweden) López, M. 2005-08-01 Full Text Available Mechanically alloyed copper-ceramic composites have been obtained with the purpose of studying their use as copper-based material for electrical equipment. For high-temperature applications, dispersion-strengthened copper alloys are attractive due to their excellent combination of thermal and electrical conductivity, mechanical strength retention and microstructural stability. In this work, powder mixtures of pure copper with 2 vol % Cr3C2, milled during 4, 6, 10, 12 and 15 h in a high-energy planetary balls mill under argon atmosphere, were consolidated by hot isostatic pressing, applying a pressure of 100 MPa at 1073 K for two hours, to obtain materials with a fine microstructure. The Cu-Cr3C2 alloys were studied by scanning electron microscopy (SEM, electron microprobe (EPMA and transmission electron microscopy (TEM. Mechanical properties and electrical conductivity were also studied. The average tensile strength and electrical conductivity were found to be 500 MPa and 50 % IACS, respectively. The Cr3C2 ceramics show good stability during hot consolidation. Contributing to a further strengthening of the alloy during the hot consolidation, uniformly-distributed Fe-carbide particles of nanometric size precipitated in the copper matrix. Fe-Cr oxycarbides formed in the interphase between Cr3C2 particles and the copper matrix cause the low ductility of Cu-Cr3C2 alloys. Said particles are attributed to impurities/contamination generated from the milling process. Se obtuvieron aleaciones compuestas de Cu-Cr3C2, aleadas mecánicamente, para estudiar futuras aplicaciones en componentes eléctricos. A altas temperaturas, las aleaciones de base cobre reforzadas por dispersión, son atractivas por su excelente conductividad térmica y eléctrica, propiedades mecánicas y estabilidad microstructural. En este estudio 18. Archaeal Nitrification in Hot Springs Science.gov (United States) Richter, A.; Daims, H.; Reigstad, L.; Wanek, W.; Wagner, M.; Schleper, C. 2006-12-01 Biological nitrification, i.e. the aerobic conversion of ammonia to nitrate via nitrite, is a major component of the global nitrogen cycle. Until recently, it was thought that the ability to aerobically oxidize ammonia was confined to bacteria of the phylum Proteobacteria. However, it has recently been shown that Archaea of the phylum Crenarchaeota are also capable of ammonia oxidation. As many Crenarchaeota are thermophilic or hyperthermophilic, and at least some of them are capable of ammonia oxidation we speculated on the existence of (hyper)thermophilic ammonia-oxidizing archaea (AOA). Using PCR primers specifically targeting the archaeal ammonia monooxygenase (amoA) gene, we were indeed able to confirm the presence of such organisms in several hot springs in Reykjadalur, Iceland. These hot springs exhibited temperatures well above 80 °C and pH values ranging from 2.0 to 4.5. To proof that nitrification actually took place under these extreme conditions, we measured gross nitrification rates by the isotope pool dilution method; we added 15N-labelled nitrate to the mud and followed the dilution of the label by nitrate production from ammonium either in situ (incubation in the hot spring) or under controlled conditions in the laboratory (at 80 °C). The nitrification rates in the hot springs ranged from 0.79 to 2.22 mg nitrate-N per L of mud and day. Controls, in which microorganisms were killed before the incubations, demonstrated that the nitrification was of biological origin. Addition of ammonium increased the gross nitrification rate approximately 3-fold, indicating that the nitrification was ammonium limited under the conditions used. Collectively, our study provides evidence that (1) AOA are present in hot springs and (2) that they are actively nitrifying. These findings have major implications for our understanding of nitrogen cycling of hot environments. 19. Monopole transitions in hot nuclei International Nuclear Information System (INIS) Sujkowski, Z. 1994-01-01 Monopole transitions can be a signature of shape changing in a hot, pulsating nucleus (the low energy E0 mode) and/or a measure of the compressibility of finite nuclei (GMR, the breathing mode). Experimental information pertaining to GMR is reviewed. Recipes for deducing the incompressibility modules for infinite nuclear matter from data on GMR are discussed. Astrophysical implications are outlined. The first attempts at locating the GMR strength in moderately hot nuclei are described. Prospects for improving the experimental techniques to make an observation of this strength in selected nuclei unambiguous are discussed. (author). 46 refs, 8 figs 20. Monopole transitions in hot nuclei Energy Technology Data Exchange (ETDEWEB) Sujkowski, Z. [Soltan Inst. for Nuclear Studies, Otwock-Swierk (Poland) 1994-12-31 Monopole transitions can be a signature of shape changing in a hot, pulsating nucleus (the low energy E0 mode) and/or a measure of the compressibility of finite nuclei (GMR, the breathing mode). Experimental information pertaining to GMR is reviewed. Recipes for deducing the incompressibility modules for infinite nuclear matter from data on GMR are discussed. Astrophysical implications are outlined. The first attempts at locating the GMR strength in moderately hot nuclei are described. Prospects for improving the experimental techniques to make an observation of this strength in selected nuclei unambiguous are discussed. (author). 46 refs, 8 figs. 1. Hot atom chemistry of sulphur International Nuclear Information System (INIS) Todorovski, D. S.; Koleva, D. P. 1982-01-01 An attempt to cover all papers dealing with the hot atom chemistry of sulpphur is made. Publications which: a) only touch the problem, b) contain some data, indirectly connected with sulphur hot atom chemistry, c) deal with 35 S-production from a chloride matrix, are included as well. The author's name and literature source are given in the original language, transcribed, when it is necessary, in latine. A number of primery and secondary documents have been used including Chemical Abstracts, INIS Atomindex, the bibliographies of A. Siuda and J.-P. Adloff for 1973 - 77, etc. (authors) 2. Construction of concrete hot cells International Nuclear Information System (INIS) 1981-12-01 The standard is to be applied to rooms (hot cells) which are enclosed by a concrete shield and in which radioactive material is handled by remote control. The rooms may be in facilities for experimental purposes (e.g. development of fuel elements and materials or of chemical processes) or in facilities for production purposes (e.g. reprocessing of nuclear fuel or treatment of radioactive wastes). The standard is to give a design hasis for concrete hot cells and their installations which is to be applied by designers, constructors, future users and competent authorities as well as independent experts. (orig.) [de 3. Construction of concrete hot cells International Nuclear Information System (INIS) 1980-09-01 The standard is to be applied to rooms (hot cells) which are enclosed by a concrete shield and in which radioactive material is handled by remote control. The rooms may be in facilities for experimental purposes (e.g. development of fuel elements and materials or of chemical processes) or in facilities for production purposes (e.g. reprocessing of nuclear fuel or treatment of radioactive wastes). The standard is to give a design basis for concrete hot cells and their installations which is to be applied by designers, constructors, future users and competent authorities as well as independent experts. (orig.) [de 4. Hot-cell verification facility International Nuclear Information System (INIS) Eschenbaum, R.A. 1981-01-01 The Hot Cell Verification Facility (HCVF) was established as the test facility for the Fuels and Materials Examination Facility (FMEF) examination equipment. HCVF provides a prototypic hot cell environment to check the equipment for functional and remote operation. It also provides actual hands-on training for future FMEF Operators. In its two years of operation, HCVF has already provided data to make significant changes in items prior to final fabrication. It will also shorten the startup time in FMEF since the examination equipment will have been debugged and operated in HCVF 5. Blood pressure Science.gov (United States) Normal blood pressure is important for proper blood flow to the body's organs and tissues. The force of the blood on the walls of the arteries is called blood pressure. Blood pressure is measured both as the heart ... 6. Hot conditioning equipment conceptual design report Energy Technology Data Exchange (ETDEWEB) Bradshaw, F.W., Westinghouse Hanford 1996-08-06 This report documents the conceptual design of the Hot Conditioning System Equipment. The Hot conditioning System will consist of two separate designs: the Hot Conditioning System Equipment; and the Hot Conditioning System Annex. The Hot Conditioning System Equipment Design includes the equipment such as ovens, vacuum pumps, inert gas delivery systems, etc.necessary to condition spent nuclear fuel currently in storage in the K Basins of the Hanford Site. The Hot Conditioning System Annex consists of the facility of house the Hot Conditioning System. The Hot Conditioning System will be housed in an annex to the Canister Storage Building. The Hot Conditioning System will consist of pits in the floor which contain ovens in which the spent nuclear will be conditioned prior to interim storage. 7. Hot conditioning equipment conceptual design report International Nuclear Information System (INIS) Bradshaw, F.W. 1996-01-01 This report documents the conceptual design of the Hot Conditioning System Equipment. The Hot conditioning System will consist of two separate designs: the Hot Conditioning System Equipment; and the Hot Conditioning System Annex. The Hot Conditioning System Equipment Design includes the equipment such as ovens, vacuum pumps, inert gas delivery systems, etc.necessary to condition spent nuclear fuel currently in storage in the K Basins of the Hanford Site. The Hot Conditioning System Annex consists of the facility of house the Hot Conditioning System. The Hot Conditioning System will be housed in an annex to the Canister Storage Building. The Hot Conditioning System will consist of pits in the floor which contain ovens in which the spent nuclear will be conditioned prior to interim storage 8. Hot-wire ignition of AN-based emulsions Energy Technology Data Exchange (ETDEWEB) Turcotte, Richard; Goldthorp, Sandra; Badeen, Christopher M. [Canadian Explosives Research Laboratory, Natural Resources Canada, Ottawa, Ontario, K1A 0G1 (Canada); Chan, Sek Kwan [Orica Canada Inc., Brownsburg-Chatham, Quebec (Canada) 2008-12-15 Emulsions based on ammonium nitrate (AN) and water locally ignited by a heat source do not undergo sustained combustion when the pressure is lower than some threshold value usually called the Minimum Burning Pressure (MBP). This concept is now being used by some manufacturers as a basis of safety. However, before a technique to reliably measure MBP values can be designed, one must have a better understanding of the ignition mechanism. Clearly, this is required to avoid under ignitions which could lead to the erroneous interpretation of failures to ignite as failures to propagate. In the present work, facilities to prepare and characterize emulsions were implemented at the Canadian Explosives Research Laboratory. A calibrated hot-wire ignition system operated in a high-pressure vessel was also built. The system was used to study the ignition characteristics of five emulsion formulations as a function of pressure and ignition source current. It was found that these mixtures exhibit complicated pre-ignition stages and that the appearance of endotherms when the pressure is lowered below some threshold value correlates with the MBP. Thermal conductivity measurements using this hot-wire system are also reported. (Abstract Copyright [2008], Wiley Periodicals, Inc.) 9. Finite orbit analysis for long wavelength modes in a plasma with a hot component International Nuclear Information System (INIS) Hammer, J.H.; Berk, H.L. 1985-01-01 The z-pinch model is used to calculate finite Larmor radius effects of a plasma with a hot component plasma annulus. The equations are analyzed for layer modes and the finite Larmor radius stabilization condition is calculated. Stability requires k 2 rho/sub h/ 2 Rβ/sub h//Δ greater than or equal to 1, where k is the wavenumber in the z-direction, rho/sub h/ the hot species Larmor radius, β/sub h/ the hot particle beta and Δ the thickness of the pressure profile. In addition a new instability is found due to the interaction of the precessional modes associated with inner and outer edges of the hot particle pressure profile 10. Solar Technician Program Blows Hot Science.gov (United States) Ziegler, Peg Moran 1977-01-01 A training program for solar heating technicians was initiated at Sonoma State College's School of Environmental Studies for CETA applicants. Among the projects designed and built were a solar alternative energy center, a solar hot water system, and a solar greenhouse. (MF) 11. The design of hot laboratories International Nuclear Information System (INIS) 1976-01-01 The need for specialized laboratories to handle radioactive substances of high activity has increased greatly due to the expansion of the nuclear power industry and the widespread use of radioisotopes in scientific research and technology. Such laboratories, which are called hot laboratories, are specially designed and equipped to handle radioactive materials of high activity, including plutonium and transplutonium elements. The handling of plutonium and transplutonium elements presents special radiation-protection and safety problems because of their high specific activity and high radiotoxicity. Therefore, the planning, design, construction and operation of hot laboratories must meet the stringent safety, containment, ventilation, shielding, criticality control and fire-protection requirements. The IAEA has published two manuals in its Safety Series, one on the safety aspects of design and equipment of hot laboratories (SS No.30) and the other on the safe handling of plutonium (SS No.39). The purpose of the symposium in Otaniemi was to collect information on recent developments in the safety features of hot laboratories and to review the present state of knowledge. A number of new developments have taken place as the result of growing sophistication in the philosophy of radiation protection as given in the ICRP recommendations (Report No.22) and in the Agency's basic safety standards (No.9). The topics discussed were safety features of planning and design, air cleaning, transfer and transport systems, criticality control, fire protection, radiological protection, waste management, administrative arrangements and operating experience 12. Interfaces in hot gauge theory CERN Document Server Bronoff, S. 1996-01-01 The string tension at low T and the free energy of domain walls at high T can be computed from one and the same observable. We show by explicit calculation that domain walls in hot Z(2) gauge theory have good thermodynamical behaviour. This is due to roughening of the wall, which expresses the restoration of translational symmetry. 13. Was the big bang hot International Nuclear Information System (INIS) Wright, E.L. 1983-01-01 The author considers experiments to confirm the substantial deviations from a Planck curve in the Woody and Richards spectrum of the microwave background, and search for conducting needles in our galaxy. Spectral deviations and needle-shaped grains are expected for a cold Big Bang, but are not required by a hot Big Bang. (Auth.) 14. A new hot pressing technique International Nuclear Information System (INIS) Carcey, J. 1975-01-01 An original hot pressing method which may be applied to ceramics, metals, and refractory powders is described. The products obtained are fine grained polycristalline materials, with homogeneous structure, very high density, unstrained and of very large dimensions (several square meters). This process equally applies to composite materials including powders, fibers, etc.. [fr 15. Hot atom chemistry of carbon International Nuclear Information System (INIS) Wolf, A.P. 1975-01-01 The chemistry of energetic carbon atoms is discussed. The experimental approach to studies that have been carried out is described and the mechanistic framework of hot carbon atom reactions is considered in some detail. Finally, the direction that future work might take is examined, including the relationship of experimental to theoretical work. (author) 16. Detection of Hot Halo Gets Theory Out of Hot Water Science.gov (United States) 2006-02-01 Scientists using NASA's Chandra X-ray Observatory have detected an extensive halo of hot gas around a quiescent spiral galaxy. This discovery is evidence that galaxies like our Milky Way are still accumulating matter from the gradual inflow of intergalactic gas. "What we are likely witnessing here is the ongoing galaxy formation process," said Kristian Pedersen of the University of Copenhagen, Denmark, and lead author of a report on the discovery. Chandra observations show that the hot halo extends more than 60,000 light years on either side of the disk of the galaxy known as NGC 5746. The detection of such a large halo alleviates a long-standing problem for the theory of galaxy formation. Spiral galaxies are thought to form from enormous clouds of intergalactic gas that collapse to form giant, spinning disks of stars and gas. Chandra X-ray Image of NGC 5746 Chandra X-ray Image of NGC 5746 One prediction of this theory is that large spiral galaxies should be immersed in halos of hot gas left over from the galaxy formation process. Hot gas has been detected around spiral galaxies in which vigorous star formation is ejecting matter from the galaxy, but until now hot halos due to infall of intergalactic matter have not been detected. "Our observations solve the mystery of the missing hot halos around spiral galaxies," said Pedersen. "The halos exist, but are so faint that an extremely sensitive telescope such as Chandra is needed to detect them." DSS Optical Image of NGC 5746 DSS Optical Image of NGC 5746 NGC 5746 is a massive spiral galaxy about a 100 million light years from Earth. Its disk of stars and gas is viewed almost edge-on. The galaxy shows no signs of unusual star formation, or energetic activity from its nuclear region, making it unlikely that the hot halo is produced by gas flowing out of the galaxy. "We targeted NGC 5746 because we thought its distance and orientation would give us the best chance to detect a hot halo caused by the infall of 17. ON THE EMERGENT SPECTRA OF HOT PROTOPLANET COLLISION AFTERGLOWS International Nuclear Information System (INIS) Miller-Ricci, Eliza; Meyer, Michael R.; Seager, Sara; Elkins-Tanton, Linda 2009-01-01 We explore the appearance of terrestrial planets in formation by studying the emergent spectra of hot molten protoplanets during their collisional formation. While such collisions are rare, the surfaces of these bodies may remain hot at temperatures of 1000-3000 K for up to millions of years during the epoch of their formation (of duration 10-100 Myr). These objects are luminous enough in the thermal infrared to be observable with current and next-generation optical/IR telescopes, provided that the atmosphere of the forming planet permits astronomers to observe brightness temperatures approaching that of the molten surface. Detectability of a collisional afterglow depends on properties of the planet's atmosphere-primarily on the mass of the atmosphere. A planet with a thin atmosphere is more readily detected, because there is little atmosphere to obscure the hot surface. Paradoxically, a more massive atmosphere prevents one from easily seeing the hot surface, but also keeps the planet hot for a longer time. In terms of planetary mass, more massive planets are also easier to detect than smaller ones because of their larger emitting surface areas-up to a factor of 10 in brightness between 1 and 10 M + planets. We present preliminary calculations assuming a range of protoplanet masses (1-10 M + ), surface pressures (1-1000 bar), and atmospheric compositions, for molten planets with surface temperatures ranging from 1000 to 1800 K, in order to explore the diversity of emergent spectra that are detectable. While current 8 to 10 m class ground-based telescopes may detect hot protoplanets at wide orbital separations beyond 30 AU (if they exist), we will likely have to wait for next-generation extremely large telescopes or improved diffraction suppression techniques to find terrestrial planets in formation within several AU of their host stars. 18. Induced Seismicity at the UK "Hot Dry Rock" Test Site for Geothermal Energy Production OpenAIRE Li, Xun; Main, Ian; Jupe, Andrew 2018-01-01 In enhanced geothermal systems (EGS), fluid is injected at high pressure in order to stimulate fracturing and/or fluid flow through otherwise relatively impermeable underlying hot rocks to generate power and/or heat. The stimulation induces micro-earthquakes whose precise triggering mechanism and relationship to new and pre-existing fracture networks are still the subject of some debate. Here we analyse the dataset for induced micro-earthquakes at the UK “hot dry rock” experimental geothermal... 19. Anisotropy effects on curvature-driven flute instabilities in a hot-electron plasma International Nuclear Information System (INIS) Spong, D.A.; Berk, H.L.; Van Dam, J.W.; Rosenbluth, M.N. 1982-08-01 The effects of finite parallel temperature are investigated for a hot electron plasma with sufficiently large beta that the magnetic field scale length (Δ/sub B/) is small compared with the vacuum field radius of curvature (R). Numerical and analytical estimates of stability boundaries are obtained for the four possible modes that can be treated in this limit: the conventional hot electron interchange, the high frequency hot electron interchange (ω > ω/sub ci/), the compressional Alfven mode, and the interacting pressure-driven interchange 20. HOT AEROSOL FIRE EXTINGUISHING AGENTS AND THE ASSOCIATED TECHNOLOGIES: A REVIEW Directory of Open Access Journals (Sweden) Xiaotian Zhang 2015-09-01 Full Text Available AbstractSince the phase out of Halon extinguishers in the 1980s, hot aerosol fire suppression technology has gained much attention. Unlike traditional inert gas, foam, water mist and Halon fire suppression agents, hot aerosol fire extinguishing agents do not need to be driven out by pressurized gases and can extinguish class A, B, C, D and K fires at 30 to 200 g/m3. Generally, hot aerosol fire extinguishing technology has developed from a generation I oil tank suppression system to a generation III strontium salt based S-type system. S-type hot aerosol fire extinguishing technology greatly solves the corrosion problem of electrical devices and electronics compared to potassium salt based generation I & II hot aerosol fire extinguishing technology. As substitutes for Halon agents, the ODP and GWP values of hot fire extinguishing aerosols are nearly zero, but those fine aerosol particles can cause adverse health effects once inhaled by human. As for configurations of hot aerosol fire extinguishing devices, fixed or portable cylindrical canisters are the most common among generation II & III hot aerosol fire extinguishers across the world, while generation I hot aerosol fire suppression systems are integrated with the oil tank as a whole. Some countries like the U.S., Australia, Russia and China, etc. have already developed standards for manufacturing and quality control of hot aerosol fire extinguishing agents and norms for hot aerosol fire extinguishing system design under different fire protection scenarios. Coolants in hot aerosol fire suppression systems, which are responsible for reducing hot aerosol temperature to avoid secondary fire risk are reviewed for the first time. Cooling effects are generally achieved through vaporization and endothermic chemical decomposition of coolants. Finally, this review discussed areas applying generation I, II or III hot aerosol fire suppression technologies. The generation III hot aerosol fire extinguishing 1. Hot Flashes amd Night Sweats (PDQ) Science.gov (United States) ... Professionals Questions to Ask about Your Treatment Research Hot Flashes and Night Sweats (PDQ®)–Patient Version Overview ... quality of life in many patients with cancer. Hot flashes and night sweats may be side effects ... 2. Hot Laboratories and Remote Handling International Nuclear Information System (INIS) Bart, G.; Blanc, J.Y.; Duwe, R. 2003-01-01 The European Working Group on ' Hot Laboratories and Remote Handling' is firmly established as the major contact forum for the nuclear R and D facilities at the European scale. The yearly plenary meetings intend to: - Exchange experience on analytical methods, their implementation in hot cells, the methodologies used and their application in nuclear research; - Share experience on common infrastructure exploitation matters such as remote handling techniques, safety features, QA-certification, waste handling; - Promote normalization and co-operation, e.g., by looking at mutual complementarities; - Prospect present and future demands from the nuclear industry and to draw strategic conclusions regarding further needs. The 41. plenary meeting was held in CEA Saclay from September 22 to 24, 2003 in the premises and with the technical support of the INSTN (National Institute for Nuclear Science and Technology). The Nuclear Energy Division of CEA sponsored it. The Saclay meeting was divided in three topical oral sessions covering: - Post irradiation examination: new analysis methods and methodologies, small specimen technology, programmes and results; - Hot laboratory infrastructure: decommissioning, refurbishment, waste, safety, nuclear transports; - Prospective research on materials for future applications: innovative fuels (Generation IV, HTR, transmutation, ADS), spallation source materials, and candidate materials for fusion reactor. A poster session was opened to transport companies and laboratory suppliers. The meeting addressed in three sessions the following items: Session 1 - Post Irradiation Examinations. Out of 12 papers (including 1 poster) 7 dealt with surface and solid state micro analysis, another one with an equally complex wet chemical instrumental analytical technique, while the other four papers (including the poster) presented new concepts for digital x-ray image analysis; Session 2 - Hot laboratory infrastructure (including waste theme) which was 3. Effects of Temperature and Pressure on Hot-Atom Reactions in Bromoethane; Effets de la Temperature et de la Pression sur les Reactions des Atomes Chauds dans le Bromoethane; Vliyanie temperatury i davleniya na reaktsii goryachikh atomov v bromehtane; Efectos de la Temperatura y de la Presion en las Reacciones de Atomos Calientes en el Bromoetano Energy Technology Data Exchange (ETDEWEB) Cole, A. J.; Mia, M. D.; Miller, G. E.; Shaw, P. F.D. [Nuclear Physics Laboratory, Oxford University, Oxford (United Kingdom) 1965-04-15 A study has been made of the yields of compounds containing Br{sup 80m} produced by irradiation of bromethane- bromine mixtures with 14 MeV neutrons at 18 Degree-Sign C, -80 Degree-Sign C and -115 Degree-Sign C, and at atmospheric pressure, and also at 18 Degree-Sign C at pressures up to 10{sup 4} atm. In addition to compounds previously reported in this system, small quantities of bromoethene, 1:2 dibromoethene, mono-and dibromopropanes, and mono-, di-, tri- and tetra-bromo- butanes have been found. There is also indirect evidence for the production of bromobutenes. The diffusion-dependent reactions are complex, and can be explained by assuming that pyrolysis of the liquid occurs in the vicinity of the hot atom to give bromoethyl radicals and ethylene. Addition of radicals to the latter then accounts for the formation of bromides containing more than two carbon atoms and for their diffusion-dependent yields. Reduction in temperature or increase in pressure generally causes an increase in yield attributable to a decreased rate of diffusion. The effect is most marked upon the yield of 1:2 dibromoethane, which is largely produced by the diffusive reaction of bromoethyl radicals and which increases fourfold by the application of 10{sup 4} atm because of the suppression of the dissociation CH{sub 2}-CH{sub 2}Br Rightwards-Arrow-Over-Leftwards-Arrow CH{sub 2} = CH{sub 2} + Br under the influence of the ''hot-spike''. By contrast, dissociation of the radical (CH{sub 3} - CHBr) into bromoethene and a hydrogen atom is energetically forbidden, and the yield of 1: 1 dibromoethane is roughly independent of pressure. The variation with temperature and pressure of the yield of bromoethane at large bromine concentrations is close to that predicted previously. (author) [French] Les auteurs ont etudie les rendements en composes contenant {sup 80m}Br produits par exposition de melanges de bromoethane-brome a des neutrons de 14 MeV aux temperatures de 18 Degree-Sign , -80 Degree 4. A study of pressureless microwave sintering, microwave-assisted hot press sintering and conventional hot pressing on properties of aluminium/alumina nanocomposite Energy Technology Data Exchange (ETDEWEB) Abedinzadeh, Reza; Safavi, Seyed Mohsen; Karimzadeh, Fathallah [Isfahan University, Isfahan (Iran, Islamic Republic of) 2016-05-15 Bulk Al/4wt-%Al{sub 2}O{sub 3} nanocomposites were prepared by consolidating nanocomposite powders using pressureless microwave sintering, microwave-assisted hot press sintering and conventional hot pressing techniques. Microstructural observations revealed that the microwave-assisted hot press sintering at different sintering temperatures of 400.deg.C and 500.deg.C resulted in more densification and smaller grain size for Al/Al{sub 2}O{sub 3} nanocomposite as compared with the conventional hot pressing. Moreover, the application of pressure in microwave sintering process led to more densification and grain growth. Mechanical properties resulting from microhardness and nanoindentation tests were also compared between three-method processed samples. It was found that the microwave-assisted hot-pressed sample exhibited higher hardness and elastic modulus in comparison with microwave-sintered and conventional hot-pressed samples. The improvement in the mechanical properties can be ascribed to lower porosity of microwave-assisted hot-pressed sample. 5. OUT Success Stories: Solar Hot Water Technology International Nuclear Information System (INIS) Clyne, R. 2000-01-01 Solar hot water technology was made great strides in the past two decades. Every home, commercial building, and industrial facility requires hot water. DOE has helped to develop reliable and durable solar hot water systems. For industrial applications, the growth potential lies in large-scale systems, using flat-plate and trough-type collectors. Flat-plate collectors are commonly used in residential hot water systems and can be integrated into the architectural design of the building 6. OUT Success Stories: Solar Hot Water Technology Science.gov (United States) Clyne, R. 2000-08-01 Solar hot water technology was made great strides in the past two decades. Every home, commercial building, and industrial facility requires hot water. DOE has helped to develop reliable and durable solar hot water systems. For industrial applications, the growth potential lies in large-scale systems, using flat-plate and trough-type collectors. Flat-plate collectors are commonly used in residential hot water systems and can be integrated into the architectural design of the building. 7. 3-D thermal stress analysis of hot spots in reactor piping using BEM International Nuclear Information System (INIS) Bains, R.S.; Sugimoto, Jun 1994-08-01 A three-dimensional steady state thermoelastic analysis has been conducted on the hot leg of a pressurized water reactor(PWR) containing localized hot spots resulting from fission product aerosol deposition occurring during a hypothetical severe accident. The boundary element method (BEM) of numerical solution was successfully employed to investigate the structural response of the hot leg. Convergence of solution can be realized provided sufficiently large number of elements are employed and correct modelling of the temperature transition region (TTR) adjacent to the hot spot on the inner surface is conducted. The only correct temperature field across the TTR is that which can be represented by the interpolation functions employed in the BEM code. Further, incorrect solutions can also be generated if the TTR is too thin. The nature of the deformation at the hot spot location depends on whether the thermal boundary condition on the outer surface of the hot leg is one of constant temperature or adiabatic. The analysis shows that at the location of the hot spot on the inner surface large compressive stresses can be established. On the outer surface at the same location, large tensile stresses can be established. The presence of these large stress elevations in the vicinity of the hot spot could be detrimental to the integrity of the hot leg. The tensile stresses are extremely important since they can act as sites of crack initiation and subsequent propagation. Once a crack propagates through the thickness, leak worthiness of the hot leg comes into question. Consequently, additional analysis incorporating the effects of plasticity and temperature dependence of the material properties must be conducted to ascertain the integrity of the hot leg. (J.P.N.) 8. Introduction of radiation protection and dosimetry in new hot cell facility in research center Rez International Nuclear Information System (INIS) Svrcula, P.; Petrickova, A.; Srba, O.; Miklos, M.; Svoboda, P. 2015-01-01 The purpose of the poster is to present radiation protection and dosimetry in the new hot cell facility being constructed as part of the SUSEN project. The hot cell facility is composed of 10 hot cells and 1 semi-hot cell. All shielding is made from steel, the outer wall shielding has thickness of 500 mm, internal wall between hot cells 300 mm with the possibility to extension to 500 mm. The ceiling shielding has a thickness of 400 mm and the floor shielding is 300 mm wide. Shielded windows allow direct view into the hot cells. Their shielding effect is equivalent to 500 mm of steel. The dimension of the window in the control room is 800 mm x 600 mm with a thickness of 900 mm. All important operating data are collected in the central system of hot cells. The system monitors under-pressure level and temperature in each chamber. If necessary it can directly control the ventilation system. Each hot cell is equipped with dose rate probes. The system also measures and evaluates airborne radioactivity in the building 9. PWR hot leg natural circulation modeling with MELCOR code Energy Technology Data Exchange (ETDEWEB) Park, Jae Hong; Lee, Jong In [Korea Institute of Nuclear Safety, Taejon (Korea, Republic of) 1997-12-31 Previous MELCOR and SCDAP/RELAP5 nodalizations for simulating the counter-current, natural circulation behavior of vapor flow within the RCS hot legs and SG U-tubes when core damage progress can not be applied to the steady state and water-filled conditions during the initial period of accident progression because of the artificially high loss coefficients in the hot legs and SG U-tubes which were chosen from results of COMMIX calculation and the Westinghouse natural circulation experiments in a 1/7-scale facility for simulating steam natural circulation behavior in the vessel and circulation modeling which can be used both for the liquid flow condition at steady state and for the vapor flow condition at the later period of in-vessel core damage. For this, the drag forces resulting from the momentum exchange effects between the two vapor streams in the hot leg was modeled as a pressure drop by pump model. This hot leg natural circulation modeling of MELCOR was able to reproduce similar mass flow rates with those predicted by previous models. 6 refs., 2 figs. (Author) 10. Status of the FRM-II hot neutron source International Nuclear Information System (INIS) Mueller, C.; Gutsmiedl, E. 2001-01-01 The new research reactor FRM-II will be equipped with a hot neutron source. This secondary source will shift a part of the thermal neutron energy spectrum in the D 2 O moderator to energies from 0.1 to 1 eV. The hot neutron source consists of a graphite cylinder (200 mm diameter, 300 mm high), which is heated by gamma radiation up to a maximum temperature of about 2400 C. The graphite cylinder is surrounded by a high-temperature insulation of carbon fiber, to achieve this high temperature. We have accomplished mock-up tests of the carbon fiber in a high temperature furnace, to investigate the insulation properties of the material. The graphite cylinder and the insulation are covered with two vessels made out of Zircaloy 4. The space between the vessels is filled with helium. The hot neutron source is permanent under control by pressure and temperature measurements. The temperature inside the graphite cylinder will be measured by a purpose-built noise thermometer due to the extremely harsh environment conditions (temperature and nuclear radiation). The hot neutron source is designed and manufactured according to the general specification basic safety and to the German nuclear atomic rules (KTA). The source will be installed in year 2001. (orig.) 11. PWR hot leg natural circulation modeling with MELCOR code Energy Technology Data Exchange (ETDEWEB) Park, Jae Hong; Lee, Jong In [Korea Institute of Nuclear Safety, Taejon (Korea, Republic of) 1998-12-31 Previous MELCOR and SCDAP/RELAP5 nodalizations for simulating the counter-current, natural circulation behavior of vapor flow within the RCS hot legs and SG U-tubes when core damage progress can not be applied to the steady state and water-filled conditions during the initial period of accident progression because of the artificially high loss coefficients in the hot legs and SG U-tubes which were chosen from results of COMMIX calculation and the Westinghouse natural circulation experiments in a 1/7-scale facility for simulating steam natural circulation behavior in the vessel and circulation modeling which can be used both for the liquid flow condition at steady state and for the vapor flow condition at the later period of in-vessel core damage. For this, the drag forces resulting from the momentum exchange effects between the two vapor streams in the hot leg was modeled as a pressure drop by pump model. This hot leg natural circulation modeling of MELCOR was able to reproduce similar mass flow rates with those predicted by previous models. 6 refs., 2 figs. (Author) 12. Recent trend of administration on hot springs Energy Technology Data Exchange (ETDEWEB) Okubo, Shigeru [Environment Agency, Tokyo (Japan) 1989-01-01 The Environmental Agency exercises jurisdiction over Hot Spring Act, and plans to protect the source of the hot spring and to utilize it appropriately. From the aspect of utilization, hot springs are widely used as a means to remedy chronic diseases and tourist spots besides places for recuperation and repose. Statistics on Japanese hot springs showed that the number of hot spring spots and utilized-fountainhead increased in 1987, compared with the number in 1986. Considering the utilized-headspring, the number of naturally well-out springs has stabilized for 10 years while power-operated springs have increased. This is because the demand of hot springs has grown as the number of users has increased. Another reason is to keep the amount of hot water by setting up the power facility as the welled-out amount has decreased. Major point of recent administration on the hot spring is to permit excavation and utilization of hot springs. Designation of National hot spring health resorts started in 1954 in order to ensure the effective and original use of hot springs and to promote the public use of them, for the purpose of arranging the sound circumstances of hot springs. By 1988, 76 places were designated. 4 figs., 3 tabs. 13. Acoustic cavitation as a mechanism of fragmentation of hot molten droplets in in cool liquids International Nuclear Information System (INIS) Kazimi, M.; Watson, C.; Lanning, D.; Rohsenow, W.; Todreas, N. 1976-11-01 A mechanism that explains several of the observations of fragmentation of hot molten drops in coolants is presented. The mechanism relates the fragmentation to the development of acoustic cavitation and subsequent bubble growth within the molten material. The cavitation is assumed due to the severe pressure excursions calculated within the hot material as a result of the pressure pulses accompanying coolant vaporization at the sphere surface. The growth of the cavitation vapor nuclei inside the hot drop is shown to be influenced by the subsequent long duration surface pressure pulses. The variation of the amplitude of these surface pulses with experimental variables is shown to exhibit the same trends with these variables as does the variation in extent of fragmentation 14. Effect of Fe on the phases and microstructure of TiC-Fe cermets by combustion synthesis/quasi-isostatic pressing International Nuclear Information System (INIS) Zhang Weifang; Zhang Xinghong; Wang Jianli; Hong Changqing 2004-01-01 Fully dense TiC-Fe cermets (x = 10, 20, 30, and 40 wt.%) were produced from Ti-C-Fe powder mixtures by combustion synthesis with quasi-isostatic pressing. The effect of Fe content on combustion temperature, combustion wave velocity, and final product density was investigated. The final product was characterized by XRD, SEM, and TEM. The combustion temperature and wave velocity decreased with increasing Fe content. Product density increased with increasing Fe content (96% at 30 wt.%). X-ray diffraction and transmission electron microscopy (TEM) revealed the final product to contain TiC, Fe phases, lath martensite, and Fe 2 Ti. The TiC particle size decreased with increasing Fe content. In addition, a low density of dislocations was observed in both the TiC particles and Fe binder, indicative of annealing and recrystallization, respectively 15. Preliminary isostatic residual gravity map of the Tremonton 30' x 60' quadrangle, Box Elder and Cache Counties, Utah, and Franklin and Oneida Counties, Idaho Science.gov (United States) Langenheim, Victoria; Oaks, R.Q.; Willis, H.; Hiscock, A.I.; Chuchel, Bruce A.; Rosario, Jose J.; Hardwick, C.L. 2014-01-01 A new isostatic residual gravity map of the Tremonton 30' x 60' quadrangle of Utah is based on compilation of preexisting data and new data collected by the Utah and U.S. Geological Surveys. Pronounced gravity lows occur over North Bay, northwest of Brigham City, and Malad and Blue Creek Valleys, indicating significant thickness of low-density Tertiary sedimentary rocks and deposits. Gravity highs coincide with exposures of dense pre-Cenozoic rocks in the Promontory, Clarkston, and Wellsville Mountains. The highest gravity values are located in southern Curlew Valley and may be produced in part by deeper crustal density variations or crustal thinning. Steep, linear gravity gradients coincide with Quaternary faults bounding the Wellsville and Clarkston Mountains. Steep gradients also coincide with the margins of the Promontory Mountains, Little Mountain, West Hills, and the eastern margin of the North Promontory Mountains and may define concealed basin-bounding faults. 16. Preliminary isostatic residual gravity map of the Newfoundland Mountains 30' by 60' quadrangle and east part of the Wells 30' by 60' quadrangle, Box Elder County, Utah Science.gov (United States) Langenheim, Victoria; Athens, N.D.; Churchel, B.A.; Willis, H.; Knepprath, N.E.; Rosario, Jose J.; Roza, J.; Kraushaar, S.M.; Hardwick, C.L. 2013-01-01 A new isostatic residual gravity map of the Newfoundland Mountains and east of the Wells 30×60 quadrangles of Utah is based on compilation of preexisting data and new data collected by the Utah and U.S. Geological Surveys. Pronounced gravity lows occur over Grouse Creek Valley and locally beneath the Great Salt Lake Desert, indicating significant thickness of low-density Tertiary sedimentary rocks and deposits. Gravity highs coincide with exposures of dense pre-Cenozoic rocks in the Newfoundland, Silver Island, and Little Pigeon Mountains. Gravity values measured on pre-Tertiary basement to the north in the Bovine and Hogup Mountains are as much as 10mGal lower. Steep, linear gravity gradients may define basin-bounding faults concealed along the margins of the Newfoundland, Silver Island, and Little Pigeon Mountains, Lemay Island and the Pilot Range. 17. Preliminary isostatic gravity map of the Grouse Creek and east part of the Jackpot 30 by 60 quadrangles, Box Elder County, Utah, and Cassia County, Idaho Science.gov (United States) Langenheim, Victoria; Willis, H.; Athens, N.D.; Chuchel, Bruce A.; Roza, J.; Hiscock, H.I.; Hardwick, C.L.; Kraushaar, S.M.; Knepprath, N.E.; Rosario, Jose J. 2013-01-01 A new isostatic residual gravity map of the northwest corner of Utah is based on compilation of preexisting data and new data collected by the Utah and United States Geological Surveys. Pronounced gravity lows occur over Junction, Grouse Creek, and upper Raft River Valleys, indicating significant thickness of low-density Tertiary sedimentary rocks and deposits. Gravity highs coincide with exposures of dense pre-Cenozoic rocks in the Raft River Mountains. Higher values in the eastern part of the map may be produced in part by deeper crustal density variations or crustal thinning. Steep linear gravity gradients coincide with mapped Neogene normal faults near Goose Creek and may define basin-bounding faults concealed beneath Junction and Upper Raft River Valleys. 18. Hot plasma parameters in Neptune's magnetosphere International Nuclear Information System (INIS) Krimigis, S.M.; Mauk, B.H.; Cheng, A.F.; Keath, E.P.; Kane, M.; Armstrong, T.P.; Gloeckler, G.; Lanzerotti, L.J. 1990-01-01 Energy spectra of energetic protons and electrons (E p approx-gt 28 keV, E e approx-gt 22 keV, respectively) obtained with the Low Energy Charged Particle (LECP) instrument during the Voyager 2 encounter with Neptune on August 24-25, 1989 are presented. The proton spectral form was a power law (dj/dE = KE -γ ), outside the orbit of Triton (∼14.3 R N ); inside that distance, it was found to be a hot (kT ≅ 60 keV) Maxwellian distribution. Such distributions, observed in other planets as well, have yet to be explained theoretically. Similarly, the electron spectral form changed from a simple power law outside Triton to a two-slope power law with a high energy tail inside. Intensity and spectral features in both proton and electron fluxes were identified in association with the crossings of the Triton and 1989 N1 L-shells, but these features do not occur simultaneously in both species. Such signatures were manifested by relative peaks in both kT and γ spectral indices. Peak proton pressures of ∼2x10 -9 dynes cm -2 , and β ∼ 0.2 were measured at successive magnetic equatorial crossings, both inbound and outbound. These parameters show Neptune's magnetosphere to be relatively undistorted by hot plasma loading, similar to that of Uranus and unlike those of Saturn and Jupiter. Trapped electron fluxes at Neptune, as at Uranus, exceed the whistler mode stably trapped flux limit. Whistler-induced pitch angle scattering of energetic electrons in the radiation belts can yield a precipitating energy flux sufficient to drive Neptune's aurora 19. PM-materials for hot working tools; PM-Werkstoffe fuer warmgehende Werkzeuge Energy Technology Data Exchange (ETDEWEB) Berns, H.; Broeckmann, C.; Theisen, W. [Bochum Univ. (Germany). Fakultaet fuer Maschinenbau; Wewers, B. 2001-05-01 Tools and wear parts for compacting tools are subjected to high abrasive wear and mechanical loading at elevated temperatures. MMC's based in iron- or nickel with hard particles are developed and investigated. The materials were manufactured from powders by hot isostatic pressing (HIP) and subsequently heat treated. Diffusion between hard phases and metal matrix brings about certain micro structures which were tested with respect to the resistance against sliding abrasion at room and elevated temperatures. Three-point bending tests and thermal cycling of the material was utilized to characterise the mechanical behaviour. Based on this results a toolkit for a roller press for briquetting was produced and brought into application. (orig.) [German] Werkzeuge und Verschleissteile fuer die Verarbeitung von mineralischen Guetern bei erhoehter Temperatur unterliegen sowohl hohem abrasivem Verschleiss als auch hohen mechanischen Lasten. Es werden hartphasenhaltige Verbundwerkstoffe auf Eisen- und Nickelbasis entwickelt und untersucht. Die Fertigung dieser MMC's erfolgt durch heiss isostatisches Pressen (HIP) und anschliessende Waermebehandlung. Durch Diffusion zwischen Hartphasen und Metallmatrix entstehen Gefuege, die bezueglich ihres Widerstandes gegen Abrasivverschleiss bei Raumtemperatur und gegen Korngleitverschliess bei erhoehter Temperatur geprueft werden. Zur Charakterisierung der mechanischen Eigeschaften werden Dreipunktbiegeversuche und thermsiche Ermuedungsversuche durchgefuehrt. Die gewonnenen Erkenntnisse werden genutzt, um einen Werkzeugsatz fuer eine Brikettierpresse herzustellen und in Einsatz zu bringen. (orig.) 20. Reduced activation ODS ferritic steel - recent development in high speed hot extrusion processing Energy Technology Data Exchange (ETDEWEB) Oksiuta, Zbigniew [Faculty of Mechanical Engineering, Bialystok Technical University (Poland); Lewandowska, Malgorzata; Kurzydlowski, Krzysztof [Faculty of Materials Science and Engineering, Warsaw University of Technology (Poland); Baluc, Nadine [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association Euratom-Confederation Suisse, Villigen PSI (Switzerland) 2010-05-15 The paper presents the microstructure and mechanical properties of an oxide dispersion strengthened (ODS), reduced activation, ferritic steel, namely the Fe-14Cr-2W-0.3Ti-0.3Y{sub 2}O{sub 3} alloy, which was fabricated by hot isostatic pressing followed by high speed hydrostatic extrusion (HSHE) and heat treatment HT at 1050 C. Transmission electron microscopy (TEM) observations revealed significant differences in the grain size and dislocation density between the as-HIPped and as-HSHE materials. It was also found that the microstructure of the steel is stable after HT. The HSHE process improves significantly the tensile and Charpy impact properties of the as-HIPped steel. The ultimate tensile strength at room temperature increases from 950 up to 1350 MPa, while the upper shelf energy increases from 3.0 up to 6.0 J. However, the ductile-to-brittle transition temperature (DBTT) remains relatively high (about 75 C).These results indicate that HSHE is a promising method for achieving grain refinement and thus improving the mechanical properties of ODS ferritic steels. (Abstract Copyright [2010], Wiley Periodicals, Inc.)	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6094048619270325, "perplexity": 6464.499090876967}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-39/segments/1568514572517.50/warc/CC-MAIN-20190916100041-20190916122041-00183.warc.gz"}
http://blog.myrank.co.in/instantaneous-velocity-and-speed/	# Instantaneous Velocity and Speed Instantaneous velocity: It is defined as the rate of change of position for a time interval which is very small almost zero. Beside Instantaneous velocity, average velocity is a way of defining how fast a body is moving. But average velocity is only the average of the velocity of body over a given time interval, and not the exact measure of velocity of a body at an instant. The exact measure of velocity of a body at an instant or over a very – very – very short time interval Δt is known as instantaneous velocity. Mathematically Instantaneous velocity of an object is the limiting value of average velocity as Δt tends towards zero. $$\underset{\Delta t\to 0}{\mathop{\lim }}\,\,\frac{\Delta x}{\Delta t}$$ And Instantaneous velocity is also the derivative of the position of the object (x) with respect to time interval (t). Instantaneous velocity = $$\frac{dx}{dt}$$ In a graph of motion of an object drawn “x” versus “t”, Instantaneous velocity of the object is the slope of tangent line drawn at the position representing that instant. Instantaneous velocity is a vector quantity and thus have its direction associated with it along with its magnitude. We know that the average velocity for a given time interval is total displacement divided by total time. As this time interval approaches zero, the displacement also approaches zero. But the limit of the ratio of displacement and time is non-zero and is called the Instantaneous velocity.If the displacement of the particle varies with respect to time and is given as (6t² + 2t + 4) m, the Instantaneous velocity can be found out at any given time by: s = (6t² + 2t + 4) Velocity (V) = $$\frac{ds}{dt}$$ $$=\,\frac{d(6{{t}^{2}}+2t+4)}{dt}$$ = 12 t + 2 So, If we have to find out the Instantaneous velocity at t = 5 sec, then we will put the value of t in the obtained expression of velocity. Instantaneous velocity at t = 5 sec = (12 x 5 + 2) = 62 m/sec Let us calculate the average velocity now for 5 seconds. Displacement = (6 x 5² + 2 x 5 + 4) = 164 m Average Velocity =$$\frac{164}{5}$$ = 32.8 m/sec Did the bullet have a speed at the instant this picture was taken? And how fast were you driving at a specific point or at a specific time? To answer these questions, we need to consider a new concept known as INSTANTANEOUS SPEED.Instantaneous Speed: We know that the average speed is for a given time interval is total distance travelled divided by the total time taken. As this time interval approaches zero, the distance travelled also approaches zero. But the limit of the ratio of distance and time is non-zero and is called the Instantaneous speed. To understand it in simple words we can also say that instantaneous speed at any given time is the magnitude of the instantaneous velocity at that time. If distance as a function of time is known to us, we can find out the instantaneous speed at any time. Let’s understand this by means of an example. Distance (s) = 5t³ m Speed (V) = $$\frac{ds}{dt}$$ $$=\frac{d(5{{t}^{3}})}{dt}$$ = 15 t² Now, we can easily find the Instantaneous speed at any given time by putting the value of t in this Obtained Expression. Real life Applications: 1. The speedometer of a car reveals information about the Instantaneous speed of your car. It shows your speed at a particular instant in time. On the average, your car was moving with a speed of 25 miles per hour. 2. A cheetah who is running with speed of 80 miles per hour then it is his Instantaneous speed because it is shown as in per hour speed. How to find Instantaneous Speed? Example: The displacement of a body is given by the equation D = at². Calculate Instantaneous speed of the body at t = 2sec, If the value of acceleration is 5 m/s²? Solution: We know that, Ins tan taneous velocity (IS) = $$\underset{T\to t}{\mathop{\lim }}\,\frac{dX}{dT}$$ So, here X = D and hence we have $$IS\,=\,\underset{t\to 2}{\mathop{\lim }}\,\frac{d(a\times {{t}^{2}})}{dt}$$ $$IS=\,\underset{t\to 2}{\mathop{\lim }}\,\,(2at)$$ IS = 2 x 5 x 2 = 20 m/sec Hence, the Instantaneous speed of the body is 20 m/sec.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.957058310508728, "perplexity": 285.3112828453485}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-51/segments/1544376824115.18/warc/CC-MAIN-20181212181507-20181212203007-00180.warc.gz"}
https://papers.nips.cc/paper/2018/hash/b4a721cfb62f5d19ec61575114d8a2d1-Abstract.html	#### Authors Jianqiao Zhu, Adam Sanborn, Nick Chater #### Abstract Both resources in the natural environment and concepts in a semantic space are distributed "patchily", with large gaps in between the patches. To describe people's internal and external foraging behavior, various random walk models have been proposed. In particular, internal foraging has been modeled as sampling: in order to gather relevant information for making a decision, people draw samples from a mental representation using random-walk algorithms such as Markov chain Monte Carlo (MCMC). However, two common empirical observations argue against people using simple sampling algorithms such as MCMC for internal foraging. First, the distance between samples is often best described by a Levy flight distribution: the probability of the distance between two successive locations follows a power-law on the distances. Second, humans and other animals produce long-range, slowly decaying autocorrelations characterized as 1/f-like fluctuations, instead of the 1/f^2 fluctuations produced by random walks. We propose that mental sampling is not done by simple MCMC, but is instead adapted to multimodal representations and is implemented by Metropolis-coupled Markov chain Monte Carlo (MC3), one of the first algorithms developed for sampling from multimodal distributions. MC3 involves running multiple Markov chains in parallel but with target distributions of different temperatures, and it swaps the states of the chains whenever a better location is found. Heated chains more readily traverse valleys in the probability landscape to propose moves to far-away peaks, while the colder chains make the local steps that explore the current peak or patch. We show that MC3 generates distances between successive samples that follow a Levy flight distribution and produce 1/f-like autocorrelations, providing a single mechanistic account of these two puzzling empirical phenomena of internal foraging.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8960916996002197, "perplexity": 1835.592174329201}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-39/segments/1631780056752.16/warc/CC-MAIN-20210919065755-20210919095755-00511.warc.gz"}
https://www.notesofdabbler.com/posts/post_2022_09_11/index.html	# Exploring OMPR with HiGHS solver R Author Notesofdabbler Published September 11, 2022 There is a class of software for modeling optimization problems referred to as algebraic modeling systems which provide a unified interface to formulate optimization problems in a manner that is close to mathematical depiction and have the ability to link to different types of solvers (sparing the user from solver specific ways of formulating the problem). Both commercial and open source options are available. GAMS and AMPL are examples of commercial options. The popular open source options are JuMP in Julia and Pyomo in python. I have typically used Pyomo in Python but have explored using it from R. I recently became aware of algebraic modeling system in R provided by OMPR package developed by Dirk Schumacher. There are commercial and open-source options available for solvers also. For a class of optimization problems referred to as Mixed Integer Linear Programs (MILP), the commercial solvers such as CPLEX, and GUROBI perform significantly better than open source solvers such as glpk, and CBC. A new open-source solver HiGHS has been developed recently that has generated quite a bit of buzz and by different accounts looks like a promising option. There is now a highs package in R that can call the HiGHS solver. In this blog, I wanted to explore using OMPR modeling system with HiGHS solver by using it to solve a few examples of LP/MILP problems. ### Example 1: Example from highs package Here I want to just describe the example in mathematical notation and show how OMPR model is close to mathematical notation. The full details of this example are in this location. #### Example Problem in highs package $\begin{array}{ll} \min & x_0 + x_1 + 3 \\ & x_1 \leq 7 \\ & 5 \leq x_0 + 2x_1 \leq 15 \\ & 6 \leq 3x_0 + 2x_1 \\ & 0 \leq x_0 \leq 4 \\ & 1 \leq x_1 \end{array}$ #### OMPR model mdl = MIPModel() %>% add_variable(x0, lb = 0, ub = 4, type = "continuous") %>% add_variable(x1, lb = 1, type = "continuous") %>% set_objective(x0+x1+3, sense = "min") %>% add_constraint(x0 + 2x1 <= 15) %>% add_constraint(x0 + 2x1 >= 5) %>% add_constraint(3x0 + 2x1 >= 6) Since OMPR can directly call HiGHS optimizer, we can solve the model and get solution as shown below. # solve model s = mdl %>% solve_model(highs_optimizer()) # get solution s$status s$objective_value s\$solution Solving the above problem results in an objective value of 5.75 and solution of (0.5, 2.25) ### Example 2: Transportation Problem This example discusses a transporation problem from GAMS model library where the goal is to find the minimum cost way to meet market demand with available plant capacity. We just show how the OMPR package can handle variables involving indices using this example. The full description of this example is in this location. $\begin{array}{llr} \min &\sum_{p=1}^P\sum_{m=1}^Mc_{pm}x_{pm} & (a) \\ &\sum_{m=1}^Mx_{pm} \leq cap_p, \;p=1,2,\ldots,P & (b)\\ &\sum_{p=1}^Px_{pm} \geq dem_m, \;m=1,2,\ldots,M & (c) \\ &x_{pm} \geq 0, \;p=1,2,\ldots,P;\;m=1,2,\ldots,M \end{array}$ where • $$x_{pm}$$ is the quantity to be shipped from plant $$p$$ to market $$m$$ (decision variable) • Objective (a) is to minimize shipping cost • Constraint (b) ensures that total supply from a plant is below capacity • Constraint (c) ensures that demand for each market is met. np = length(plants) nm = length(mkts) # create ompr model mdl = MIPModel() %>% add_variable(x[i, j], i=1:np, j=1:nm, type = "continuous",lb = 0) %>% # objective: min cost set_objective(sum_over(cost(i, j) * x[i, j], i = 1:np, j = 1:nm), sense = "min") %>% # supply from each plant is below capacity add_constraint(sum_over(x[i, j], j = 1:nm) <= cap[i], i = 1:np) %>% # supply to each market meets demand add_constraint(sum_over(x[i, j], i = 1:np) >= dem[j], j = 1:nm) The figure on the left show the supply network (plants on top and markets below with numbers being capacity for plants and demand for markets). The figure on the right shows the solution where Chicago market is supplied by Seattle plant and San Diego plant supplies both New York and Topeka markets. Network Information Solution ### Example 3: Map Coloring Problem This example discusses a map coloring problem where the goal is to use the minimum number of colors so that no two adjacent states in the US map have the same color. In this example also, I am just showing the mathematical formulation and OMPR model. The full description of this example is in this location. $\begin{array}{llr} \min & \sum_{c=1}^Cy_c & (a)\\ & \sum_{c=1}^Cx_{ic} = 1, \;i=1,2,\ldots,N & (b)\\ & x_{ic} + x_{jc} \leq y_c, \; \mbox{when }i, j \mbox{ are adjacent} & (c)\\ & x_{ic} \; binary \\ & y_c \; binary \end{array}$ where: • $$y_c=1$$ if color $$c$$ is used, $$x_{ic}=1$$ if state $$i$$ is colored with color $$c$$. • Objective (a) is to minimize the number of colors used • Constraint (b) ensures that each state gets some color • Constraint (c) ensures that if state $$i$$ and $$j$$ are adjacent, they don’t get the same color. # OMPR model ns = nrow(nodes_df) nc = 4 edge_str = edge_df %>% mutate(edge_str = glue("{fromid}_{toid}")) %>% pull(edge_str) mdl = MIPModel() mdl = mdl %>% add_variable(x[i, c], i = 1:ns, c = 1:nc, type = "integer", lb = 0, ub = 1) mdl = mdl %>% add_variable(y[c], c = 1:nc, type = "integer", lb = 0, ub = 1) mdl = mdl %>% set_objective(sum_over(y[c], c=1:nc), sense = "min") mdl = mdl %>% add_constraint(sum_over(x[i, c], c = 1:nc) == 1, i = 1:ns) mdl = mdl %>% add_constraint(x[i, c] + x[j, c] <= y[c], i = 1:ns, j = 1:ns, c = 1:nc, glue("{i}_{j}") %in% edge_str) Solving this problem give the following map coloring	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 2, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.20917962491512299, "perplexity": 3507.6789964058853}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-49/segments/1669446710926.23/warc/CC-MAIN-20221203075717-20221203105717-00735.warc.gz"}
https://asmedigitalcollection.asme.org/turbomachinery/article/145/6/061017/1156453/Experimental-Study-of-Impact-of-In-Service	## Abstract In this paper we experimentally evaluate the impact of in-service deterioration on the aerodynamic performance of heavily film-cooled high-pressure nozzle guide vanes from large civil jet engines. We study 15 mid-life to end-of-life parts removed from operational engines, and compare their performance to those of new parts. Deterioration features included: increased surface roughness; thermal barrier coating spallation; damaged film cooling holes; and trailing edge burn-back. We characterize and present statistics for the surface roughness. Aerodynamic measurements were performed in the high technology readiness level Engine Component AeroThermal (ECAT) facility at the University of Oxford, at engine-representative conditions of exit Mach number, exit Reynolds number, coolant-to-mainstream pressure ratio, and turbulence intensity. We present detailed experimental measurements of the coolant capacity characteristics, downstream loss, and downstream flow structures. The results show that service time has the following effects on high-pressure nozzle guide vanes: increased equivalent sandgrain roughness of (up by 1056% change); reduced coolant flow capacity (maximum change of −6.27% for film cooling holes and −24.7% for the trailing edge slot); increased overall mixed-out kinetic energy loss coefficient by (up to 33% change); leads to greater downstream flow angle variation (change of −6 deg). This is one of the first significant studies of its type in the open literature, and is an important step towards whole-life engine performance assessment. ## Introduction and Related Literature High-pressure (HP) nozzle guide vanes (NGVs) deteriorate with service time due to (see, for example [1]) oxidation, deposition of airborne contaminants, thermal fatigue cracking (e.g., of the thermal barrier coat (TBC) layer), and erosion due to impact-abrasion [2]. These effects lead to both local changes in surface roughness, and global changes in geometry. Thermal barrier coating spallation and cracking is common, as is the partial collapse of cooling holes (smaller effective size), or the blockage or geometry change of holes due to particulate deposition. Eroded trailing edges (TE), or TE burn-back due to overheating are also common. These effects generally reduced the aero-thermal performance of the parts. The purpose of this paper is to perform accurate aerodynamic characterization of engine-run parts. We first review the literature related to the impact of surface roughness and TE damage on aerodynamic performance. ### Impact of Surface Roughness. There have been several cascade experiments to assess the impact of surface roughness on the aerodynamic performance of turbine components. Most of these studies have used simple simulated roughness elements (sandgrains, hemispheres, and truncated cones) [35] or surface finishes arising from manufacturing processes (e.g., machining processes, polishing processes, and coating types) [611], with only one study (to the authors knowledge) attempting to simulate engine-representative roughened surfaces on an airfoil [12]. A comprehensive review of literature (up to 2010) on effects due to roughness was provided by Bons [13]. As expected, the primary effects are earlier laminar-turbulent boundary layer transition, and an increased rate of thickening of the boundary layer (in both states), leading to higher aerodynamic loss. One exception is the case of low Reynolds number (Re) operation (low pressure turbines for instance) where an earlier roughness-induced transition has been shown to prevent a laminar separation on the suction surface (SS) of the airfoil, leading to lower losses than a smooth (separated) airfoil [10,13,14]. This general effect is—of course—well known. We can differentiate between studies in which the surface roughness of the entire airfoil is varied evenly to represent possible manufacturing routes [3,4,610], for example, metal printing techniques, and those in which the roughness on only part of the surface is varied [5,11,12]. These latter studies are more representative of in-service roughening which appears to preferentially affect the pressure surface (PS) and early SS. Kind et al. [5] performed aerodynamic surveys 0.4 axial chords (Cax) downstream of a low-speed linear cascade of turbine blades to study the impact of roughness on profile loss. The inlet ReC (based on tangential chord) was 3.0 × 105. They tested 18 cascade configurations: one smooth cascade configuration in which the airfoil surface (PS and SS) and endwalls are reported to be aerodynamically smooth (roughness height not reported) and 17 other configurations in which spanwise-oriented bands of roughness (application of sand grains) were introduced at different locations around the airfoil. The roughness distribution most relevant to the current study was a roughened band covering approximately 30‒100% of the PS with the rest of the airfoil being smooth. For this distribution, two sandgrain roughness heights (k) were used: k/C = 4.5 × 10−3 and 6.3 × 10−3, where C is the tangential chord. They reported that at the design incidence angle the profile loss increased from the smooth configuration by approximately 30% and 40% for the two roughness heights, respectively. Matsuda et al. [11] performed aerodynamic surveys 0.165 tangential chords downstream of a linear cascade of vanes to study the impact of airfoil and endwall roughness on profile loss and net secondary loss. Net secondary loss was defined as the difference between the total pressure loss measured in the secondary flow region, and the estimated profile loss (based on mid-span measurements). The exit ReC (based on tangential chord) range was 0.30 × 106 < ReC < 1.0 × 106 and inlet turbulence intensity (Tu) was 0.43%. They tested two configurations: a smooth cascade configuration in which the airfoil surface (PS and SS) and endwalls had a normalized maximum peak-to-valley roughness height Rz/C of 5.2 × 10−5 (typical of a milled surface of a new steam turbine vane); and a rough cascade configuration in which the PS and endwalls had Rz/C equal to 84.0 × 10−5 (approximately 16 times larger than the smooth configuration, and typical of a shot blasted surface), and with the SS essentially unchanged from the smooth case with Rz/C equal to 6.0 × 10−5. At ReC = 0.87 × 106, they found that the profile loss and net secondary loss for the rough configuration increased by approximately 36% and 80%, respectively, compared to the smooth configuration. The measured increase in loss was similar in magnitude to the study of Kind et al. [5], despite an almost order-of-magnitude difference in reported surface roughness height. This apparently surprising result may be explained by a combination of two factors: the peak-to-valley roughness height, Rz, and sandgrain roughness height, k, both fail to take account of shape and density of the roughness elements in the profile; the roughness types are different, one surface being artificially roughened (sand grains) and the other being the result of a manufacturing process. Differences in roughness type and quantification make the comparison between studies difficult. Erickson et al. [12] studied the impact of in-service roughening on the aerodynamic performance of turbine vanes in a low-speed linear cascade over a wide range of Tu and Re. Because of the similarity of their study to the current experiment (in terms of roughness type, distribution, modeling method, height, and operating conditions of Re and Tu) we consider the Erickson et al. [12] study an important reference point when it comes to the aerodynamic impact of roughness. At the closest condition to our experiment an increase in midspan total pressure loss coefficient of 12% was measured. We devote a later section of this paper to a more detailed comparison of our work and that of Erickson et al. [12]. The purpose is to allow detailed comparison of very similar studies, in the hope of cross-validation of the results, and in the hope of developing a benchmark loss-enhancement factor for typical engine geometries under engine realistic conditions. Comparison to existing correlations would be desirable, but is problematic, because, as demonstrated in the extensive review of Bons [13], variation in roughness type (simulated, manufacturing-related, and service-related) appears to have a significant effect on the correlation, and therefore a single global correlation remains elusive. It may be the case that in the foreseeable future it is necessary to perform high-fidelity studies of the type presented in this paper, in the hope of direct rules-of-thumb for particular combinations of part-type and deterioration characteristic. ### Impact of Trailing Edge Damage. We now review the literature on the impact of TE damage on the aerodynamic characteristics of turbine components. Sjolander et al. [15] studied the impact of a semi-circular cutout in the TE of a turbine blade (to simulate damage caused by burn-back or erosion) on loss and flow turning angle. Using a low-speed linear cascade, they did aerodynamic surveys downstream of an undamaged blade and two blades with a semi-circular cutout in their TE with diameters equivalent to 15% and 25% of the blade tangential chord. Results showed that the wake downstream of the cutout was significantly modified, with local under-turning of the flow (up to 4.2 deg yaw angle deficit compared to a new blade) in the cutout region. They also observed the formation of counter-rotating streamwise vortices at the edges of the cutout, driven by the sharp gradients (with radius) in yaw angle. Similar flow structures have been observed in computational fluid dynamics (CFD) studies of vanes with TE damage by Di Mare et al. [16] and Meyer et al. [17]. Sjolander et al. reported that the mass-flux-average profile total pressure loss coefficient increased by 56% (compared to undamaged blade) for the deepest cutout. Bouchard et al. [18] did aerodynamic surveys downstream of full rings of uncooled new and in-service deteriorated engine vanes in a transonic annular cascade. The vanes were those of a Rolls-Royce A-250 engine. The TE of the deteriorated vanes had small chordwise cracks, and some TE were significantly thermally distorted. No surface roughness measurements were reported in the paper. Profile loss measurements were taken one half of an axial chord downstream of the vanes at exit Mach number (M) M = 1.2. They reported an increase in profile loss of 51% for the deteriorated vane ring. ### Objective of This Study. Although there is a small body of literature which presents results of studies of simulated deterioration features in isolation, there are very few studies indeed [18] which characterize components with in-service deterioration. Although the overall impact of deterioration could reasonably be expected to be well-modeled by superposition of the individual deterioration effects, for the purpose of building whole-life turbine performance models it is important to characterize real engine parts at various stages through the life cycle. There is very little data available for this task. The purpose of this paper—and the main distinction from previous studies—is to characterize the range of aerodynamic performance that exists for real-engine HP NGVs subject to in-service deterioration. The data provide a reference point for whole-life performance modeling. To this end, for 15 engine-run parts, we present detailed measurements of: surface roughness; coolant capacity; and aerodynamic performance. Measurements were conducted for parts operating under engine-representative conditions of exit M and exit Re. The data are to be used to benchmark whole-life modeling codes. ## Characterization of Tested Components In this study we experimentally characterize a total of 17 real-engine vanes. The vane design was that from a modern large civil jet engine. The vanes were divided in two sets, referred to as set 1 and set 2. Set 1 was composed of one new vane and 12 mid-life vanes and set 2 was composed of one new vane and three end-of-life vanes. The new vane within each set has the same as-new geometry as the deteriorated vanes in the same set and acts as a baseline for that set. The deteriorated vanes within each set are from the same engine, and therefore were operated in the same environment and for the same number of cycles. The two sets operated in a non-sandy, yet not identical, environment. A summary of the operation history of both sets of vanes is given in Table 1. Table 1 Descriptive summary of the operation history of the in-service deteriorated parts in set 1 and set 2 ParameterSet 1Set 2 Number of vanes12 (+1 new)3 (+1 new) Position in life cycleMid-lifeEnd-of-life Operating environmentNon-sandyNon-sandy ParameterSet 1Set 2 Number of vanes12 (+1 new)3 (+1 new) Position in life cycleMid-lifeEnd-of-life Operating environmentNon-sandyNon-sandy Although the vanes in set 1 and set 2 are from the same engine-class, they are from different generations of the same engine and have slightly different geometries. Thus, comparisons between sets should be avoided. All vanes were fully featured, including film cooling holes, TE slots, and TBC. We identify individual vanes using their set number (S1 or S2) and vane number within the set (V1, V2, etc.). Although experimental data were acquired for all vanes in both sets, in this paper we focus on data from four vanes for each set: one new vane and three deteriorated vanes. For the focused study, we chose the vanes with deterioration patterns representative of the full population of vanes. We refer to selected set 1 vanes as: S1-V1 (new); and S1-V2, S1-V3, and S1-V4 (mid-life). The corresponding nomenclature for set 2 is: S2-V1 (new); and S2-V2, S2-V3, and S2-V4 (end-of-life). Although we present detailed measurements for only this sample, we present statistics on the parent set of parts where space allows. We now characterize the deterioration of the tested vanes. First we consider TE burn-back and TBC spallation, then we present surface roughness measurements. ### Trailing Edge Burn-Back and Thermal Barrier Coat Spallation. Figure 1 shows a schematic of the vanes in set 1 (S1) and set 2 (S2). Film cooling holes and the TE slots are omitted for clarity. The vane outline is shown by a solid outline. Solid and dashed lines on the vane surface demarcate regions of TE burn-back and TBC spallation, respectively. Fig. 1 Fig. 1 Close modal We consider first the selection of set 1 parts: one reference vane and three mid-life vanes. Vanes S1-V1 to S1-V4 are illustrated in Fig. 1(a). We see TE burn-back for vanes S1-V2 and S1-V3, with notches at approximately mid-span that extend to a depth equal to approximately 5% of the tangential chord and up to 18% of the span of the vane. There is a small region of TBC spallation at the leading edges (LE) close to the stagnation point for vanes S1-V3 and S1-V4. These regions are narrow and cover less than 10% of the span of the vanes. The TE burn-back and TBC spallation on vanes S1-V2 to S1-V4 are representative of the damage of the other deteriorated vanes in set 1. Now we consider the set 2 parts: one reference vane and three end-of-life vanes. With reference to Fig. 1(b), we see both significant TE burn-back and significant TBC spallation. Looking first at the TE damage, vane S2-V2 was burned back up to 14.2% of the tangential chord and the damage covers 80% of the span of the vane. The TE of vane S2-V3 is burned back up to 9.6% of the tangential chord at midspan and the damage covers 40% of the span of the vane. The TE of vane S2-V4 is slightly cracked and distorted towards the SS, with TE TBC spallation on both the PS and SS extending up to 7% of the tangential chord over 35% of the span of the vane. It is suspected that the TE damage is the result of local overheating rather than erosion (by, for example, sand) because approximately half of the vanes from the same engine had relatively undeteriorated TE. Now consider the LE region damage for the set 2 (end-of-life) vanes. The LE of all vanes in this set were severely damaged with TBC spallation covering up to 65% of the span of the vanes, and extending as far as 30% of the tangential chord on the PS of the vanes (see Fig. 1(b)). The spallation was so severe in some places that the metal was left unprotected. This is thought to be due to a combination of thermal fatigue cracking and oxidation. In the regions of most severe deterioration, primarily in the showerhead region of the parts, there was significant collapse (shrinkage of diameter, and damage to form) of the cooling holes, and cracking between holes. A descriptive summary of the deterioration characteristics of both sets of vanes is given in Table 2. Table 2 Descriptive summary of deterioration characteristics of the set 1 (mid-life) and set 2 (end-of-life) parts VaneLE geometryTE geometry S1-V1NewNew S1-V2IntactSmall notch at midspan S1-V3Minor TBC spallationSmall notch at midspan S1-V4Minor TBC spallationIntact S2-V1NewNew S2-V2Severe TBC spallation; collapsed cooling holes; cracking between holes Burn-back along the entire span S2-V3Severe TBC spallation; collapsed cooling holes; cracking between holes Burn-back at midspan S2-V4Severe TBC spallation; collapsed cooling holes; cracking between holes Minor distortion and cracking; minor TBC spallation VaneLE geometryTE geometry S1-V1NewNew S1-V2IntactSmall notch at midspan S1-V3Minor TBC spallationSmall notch at midspan S1-V4Minor TBC spallationIntact S2-V1NewNew S2-V2Severe TBC spallation; collapsed cooling holes; cracking between holes Burn-back along the entire span S2-V3Severe TBC spallation; collapsed cooling holes; cracking between holes Burn-back at midspan S2-V4Severe TBC spallation; collapsed cooling holes; cracking between holes Minor distortion and cracking; minor TBC spallation ### Surface Roughness Measurements. In this section we present surface roughness measurements for the tested vanes. Profilometry measurements were performed using an Alicona InfiniteFocus profilometer (non-contact optical three-dimensional surface measurement system). Measurements were taken at three span fractions and three streamwise positions on the PS, and at three span fractions and four streamwise positions on the SS. These 21 locations are indicated in Fig. 2. Each profilometry measurement covered a 500 µm × 500 µm area and consisted of 250,000 (500 × 500) discrete points. The measurement resolution in the wall-normal direction (z) direction was 0.1 µm. The macroscopic surface shape was evaluated by cubic surface fitting and was removed from the measurement to only keep the surface profile. Figure 3 shows examples of the measured and processed surface profiles. The positive streamwise direction is along the x axis. The data show good measurement resolution. The new TBC surface profile (Fig. 3(a)) was measured at 50% span at position PS2 (Fig. 2) on vane S1-V1 and is characterized with a high density of shallow and blunt valleys. The deteriorated TBC surface profile (Fig. 3(b)) was measured at 50% span at position PS2 on vane S1-V2 and is characterized by sharper high peaks formed by deposits. The shape of the peaks appears to be independent of direction (streamwise or spanwise). Fig. 2 Fig. 2 Close modal Fig. 3 Fig. 3 Close modal We represent roughness at the measurement locations with an equivalent sandgrain roughness height (ks) using the methodology proposed by Bons [19]. We present ks normalized by the tangential chord C of the vanes. Figure 4 shows ks/C measured on vanes S1-V1 to S1-V4 for set 1 and S2-V1 to S2-V4 for set 2 (entire set). Fig. 4 Fig. 4 Close modal Plots (a) and (b) show data for the PS of the vanes in set 1 and set 2, respectively. Plots (c) and (d) show data for the SS of the vanes in set 1 and set 2, respectively. Position labels indicate: the side of the vane (PS or SS); streamwise position (1–3 on PS and 1–4 on SS, as shown in Fig. 2); and span fraction (20%, 50%, and 80%). Each bar at a given position corresponds to a particular vane measurement. Consider first the vanes in set 1 (mid-life) part data of Figs. 4(a) and 4(c). On the PS and early SS (SS/1/XX locations, where XX = 20, 50, or 80) we see a significant increase in ks/C of the deteriorated vanes compared to the new vane. The mean increase in these 12 locations was 441%, with a maximum increase of 1056%. On the remainder of the SS (locations SS/2–4/XX) the deteriorated and new vanes are more similar, with a mean increase in roughness of 53.3%, and a maximum increase of 192%. This is in accord with the result of Bons et al. [20], who documented the surface roughness on nearly 100 in-service-deteriorated turbine components and noted that the PS and early SS suffer from in-service roughening much more than the late SS. Now consider the set 2 (end-of-life) part data of Figs. 4(b) and 4(d). The early PS (locations PS/1/XX) and early SS (locations SS/1/XX) show a significant increase in roughness compared to the new vane, with a mean increase in roughness of 104% and a maximum increase of 723%. In all other locations on the vane the increase in roughness is smaller, with a mean increase of 49.5%, and a maximum increase of 201%. Taking all vanes within set 1 (mid-life) (entire set of 12 deteriorated vanes and one new vane), the mean values of ks/C across all measurement points were 0.109 × 10−3 for the new vane and 0.399 × 10−3 for the deteriorated vanes (average of 12 vanes). The average increase in roughness (compared to the new vanes) was 266%. This was strongly biased towards the PS and the early SS (locations SS/1/XX). Taking the vanes within set 2 (end-of-life) as a whole (three deteriorated vanes in total and one new vane), the mean values of ks/C across all measurement points were 0.103 × 10−3 for the new vane and 0.185 × 10−3 for the deteriorated vanes (average of three vanes). The average increase in roughness (compared the new vanes) was 79.6%. Again, this was strongly biased towards the PS and the early SS (locations SS/1/XX). Although in this paper we focus on the airfoil surface, for completeness we note that the hub and casing platforms of the deteriorated vanes of both set 1 and set 2 were qualitatively rougher than new platforms, but without major geometrical deviations. ## Overview of the Experimental Facility Aerodynamic measurements were conducted in the Engine Component AeroThermal (ECAT) facility at the University of Oxford [21]. This is a high technology readiness level (TRL) blowdown facility capable of testing an annular cascade of HP NGVs from operating engines at engine-representative conditions of Mach number, Reynolds number, and coolant-to-mainstream pressure ratio. A schematic cross section of the facility working section with the traverse system installed is presented in Fig. 5. Fig. 5 Fig. 5 Close modal ### Operating Conditions. During a test, high-pressure air (initially stored in large tanks) is discharged through the cascade of vanes. Steady operating conditions can be achieved for approximately 60 s by the action of a pressure regulator upstream of the cascade. During this time aerodynamic traverse measurements are taken. The vanes are supplied with coolant from the hub and case (see Fig. 5), feeding the vane film cooling holes and the TE slot. Further details on the operation of the ECAT facility can be found in Refs. [2123]. The operating conditions used in this study are summarized in Table 3. Table 3 ECAT facility operating conditions for aerodynamic measurements of this study ParameterValue Mean vane pressure ratio, p2/p010.58 Mean vane isentropic exit Mach no., M2,is0.92 Exit Reynolds no., ReC1.60 × 106 Vane inlet turbulence intensity, Tu12% Coolant-to-mainstream pressure ratio, p0c/p011.027 Coolant mass ratio, $m˙c/m˙$10% ParameterValue Mean vane pressure ratio, p2/p010.58 Mean vane isentropic exit Mach no., M2,is0.92 Exit Reynolds no., ReC1.60 × 106 Vane inlet turbulence intensity, Tu12% Coolant-to-mainstream pressure ratio, p0c/p011.027 Coolant mass ratio, $m˙c/m˙$10% ### Instrumentation for Aerodynamic Measurements. Mainstream total pressure and total temperature measurements at the cascade inlet (p01 and T01) were performed using probe rakes (approximate axial location shown in Fig. 5) at four circumferential positions around the annulus. Hub and case coolant cavity total pressure and total temperature (p0c and T0c) were also measured at four circumferential positions. The vane exit static pressure (p2,hub and p2,case) was measured on six vanes (from a total of 40) with 28 tappings per vane (84 tappings in total) located on the hub and case platform overhangs approximately 5 mm downstream of the cascade TE plane (see Fig. 5). Area surveys were conducted in an axial plane one-quarter of an axial chord downstream of the HP NGV TE using an automated radial-circumferential hub-mounted traverse gear. The location and approximate geometry of the traverse are shown in Fig. 5. The probe tip is approximately aligned with the mean flow angle, to ensure measurements were in the range of minimum error for the probe system. Aerodynamic measurements were taken using a five-hole probe (tip diameter 2.8 mm) calibrated over a wide Mach number range (0.3 ≤ M ≤ 1.4). The probe was calibrated to allow determination of total and static pressures, Mach number, and flow angles. Data on a full area-traverse plane are built from six discrete blocks (separate runs) which are then stitched together. A full-area traverse map contains approximately 60 traverse passes with a radial step size of approximately 1 mm. Better than 1 mm effective resolution is obtained in the circumferential direction. More details on the instrumentation and measurement processing for the ECAT facility can be found in Refs. [21,23]. ### Coolant Flow Capacity Measurement Process. We define in-situ coolant capacity as the capacity measured in the presence of main flow, i.e., $Γc(p0cp01,p2p01)=m˙c(p0cp01,p2p01)T0cp0c$ (1) where $m˙c$ is the total coolant mass flowrate, and p0c and T0c are the total pressure and total temperature of the coolant flow in the feed plenum. Likewise, ex-situ capacity is that measured in a bench test experiment with an atmospheric back-pressure condition (in the absence of the potential field developed by the vane in the presence of main flow) $Γc(p0cpatm)=m˙c(p0cpatm)T0cp0c$ (2) Ex-situ capacity measurements were performed individually on all 17 vanes (2 new vanes and 15 deteriorated vanes) used in this study. It is necessary to perform ex-situ measurements on individual parts to separate effects on a per-vane basis. It is—of course—impossible in practice to measure the change in in-situ coolant capacity on a vane-by-vane basis because there is a common feed to the entire vane ring. It is possible however, to accurately infer the per-vane in-situ capacity from the per-vane ex-situ capacity measurements. The following process was used: • Ex-situ capacity measurements were performed on individual deteriorated vanes and non-deteriorated vanes. In these experiments the TE slot capacity characteristic and the capacity characteristic for all film cooling rows were separately determined. These experiments define the absolute ex-situ capacity characteristics of the individual vanes. • The ratios between individual film row capacity characteristics were taken from the design intent (validated against earlier experiments). These ratios were assumed to be unchanged with deterioration. The inferred overall in-situ cooling capacity can be shown to be relatively independent of these ratios over a relatively wide range of variation. • A low-order flow-capacity model for the in-situ part was developed in which—for each film row—an average film-row exit pressure at a particular vane operating point (p2/p01) was defined from CFD simulations at that operating point. Absolute capacity (all films and TE slot) come from the ex-situ experiments; ratios between rows come from the design intent. This low-order model allows prediction of individual capacity values for rows operating at particular local pressure ratios p0c/px, where px is the local static pressure defined by the vane pressure ratio and the vane aerodynamics. This allows the in-situ capacity on a per-vane basis to be calculated as a function of vane operating point (p2/p01) and coolant-to-mainstream pressure ratio (p0c/p01). By summation the overall in-situ coolant capacity can be calculated as a function of vane operating point and coolant-to-mainstream pressure ratio. • Separate in-situ experiments of overall coolant capacity were performed and compared to the predicted value of in-situ coolant capacity from the low-order model (based on the ex-situ measurements and CFD boundary conditions). These values agreed to within 1.1% giving confidence in this check-sum validation of the low-order model. • Once the check-sum was performed, the low-order model could be used to predict overall film capacity and TE slot capacity on a per-vane basis. This can be done for any particular combination of p2/p01 and p0c/p01. This enables us to predict per-vane variation in film and TE-slot capacity for the individual deteriorated vanes of this study. This is a simple process, relatively accurate to first-order. In a more sophisticated analysis a fully-coupled internal-external network loss model would be used, with individual deteriorated parts would be characterized on a per-film-row basis in the ex-situ experiments. This would enable extremely accurate predictions for the in-situ environment. Such an approach is discussed in Ref. [24]. The improved process is arduous in practice, however, and for the purpose of studying the overall change in in-situ coolant capacity from the situation for undamaged vane, we believe the simple process to be at least adequate. Bench-test measurements were taken in an experiment in which the NGV was fed from both the hub and case using custom-made (plastic printed) feed plena sealed to the vane with wax sealant (to ensure complete removal). The feed plena were pressure-balanced using variable metered feeds fed from a constant pressure (regulated) supply. Total temperature and total pressure were measured upstream of the NGV coolant inlet using measurement rakes. The flow discharged directly to atmosphere through the film cooling holes and the TE slot. Test data were taken at five coolant-to-mainstream pressure ratios, p0c/patm = 1.1, 1.2, 1.4, 1.6, and 1.8. At the nominal coolant-to-mainstream pressure ratio and nominal vane pressure ratio (Table 3) the coolant-to-overall (mainstream plus coolant) mass flowrate ratio was approximately 10%, of which approximately one-tenth was the TE slot flow. Using the ex-situ capacity measurements we express proportional changes (from the undamaged vane) in ex-situ per-row coolant capacity (e.g., Γc,S1–VXΓc,S1–V1)/Γc,S1–V1, where X = 2, 3, or 4). That is, changes between the individual deteriorated and undeteriorated parts. As these results are approximately independent of pressure ratio, we present average values (from all tested pressure ratios). For unchanged in-situ aerodynamics the proportional change in per-row in-situ capacity is the same as the proportional change in the per-row ex-situ capacity. The same statement is equally true for any group of cooling rows, and independently for the TE slot. In our particular tests we consider two groups: the TE slot; and the entire flow from 11 film cooling rows. These results are presented in a later section. ## Experimental Results The experimental results are now presented. We will consider: coolant capacity measurements; local kinetic energy (KE) loss coefficient distributions; plane-average and mixed-out KE loss coefficients; comparisons to open-literature data of loss enhancement due to increased surface roughness; circumferential profiles of local KE loss coefficient; and radial distributions of flow angle. ### Coolant Flow Capacity Measurements. In this section we consider the measurements of ex-situ coolant capacity which—we have explained—is a reasonable proxy for in-situ coolant capacity in our experiments. The proportional changes in coolant capacity (Γc,S1–VXΓc,S1–V1)/Γc,S1–V1 for set 1 and (Γc,S2–VXΓc,S2–V1)/Γc,S2–V1 for set 2) are presented in Table 4. The measurement process allows separation of the TE slot flow and the film flow. Proportional changes are relative to the reference (new) vane in each set. Table 4 Proportional changes in coolant capacity Set 1 vane(Γc,S1–VXΓc,S1–V1)/Γc,S1–V1 (%) Film holesTE slot S1-V2‒5.37‒13.4 S1-V3‒6.21‒15.0 S1-V4‒3.87‒2.54 Mean S1-V(2–4)‒5.15‒10.3 Mean S1-V(2–12)‒2.20‒4.87 (Γc,S2–VXΓc,S2–V1)/Γc,S2–V1 (%) Set 2 vaneFilm holesTE slot S2-V2‒5.62‒24.7 S2-V3‒5.43‒15.9 S2-V4‒6.27‒9.79 Mean S2-V(2–4)‒5.77‒16.8 Set 1 vane(Γc,S1–VXΓc,S1–V1)/Γc,S1–V1 (%) Film holesTE slot S1-V2‒5.37‒13.4 S1-V3‒6.21‒15.0 S1-V4‒3.87‒2.54 Mean S1-V(2–4)‒5.15‒10.3 Mean S1-V(2–12)‒2.20‒4.87 (Γc,S2–VXΓc,S2–V1)/Γc,S2–V1 (%) Set 2 vaneFilm holesTE slot S2-V2‒5.62‒24.7 S2-V3‒5.43‒15.9 S2-V4‒6.27‒9.79 Mean S2-V(2–4)‒5.77‒16.8 Looking first at the set 1 data, we see a reduction in coolant capacity for all the mid-life deteriorated vanes for both film cooling holes and TE slot. For the film cooling flow the reduction in capacity is between ‒6.21% and ‒3.87% with an average (across three parts) of ‒5.15%, and for the TE slot the reduction is between −15.0% and −2.54% with an average of −10.3% (across three parts). The decrease in film coolant capacity appears to be caused by partial blockage of the holes due to particle deposition. This is marked A in Fig. 6(b). The condition of an undamaged film cooling hole is shown in Fig. 6(a). Close inspection of the film cooling holes of the mid-life vanes shows some level of deposition in all holes. The decrease in TE slots coolant capacity appears to be due to partial collapse of the TE slot, due to overheating and thermal distortion. This is shown in Fig. 6(c), marked B. Most mid-life vanes showed partial collapse in some areas, even on vanes without TE burn-back, but the effect was more advanced on vanes which also showed TE burn-back (e.g., S1-V2 and S1-V3). Taking the average across all vanes in set 1 (total of 12 mid-life vanes; not individually reported in Table 4) we find a mean reduction in film cooling flow capacity of ‒2.20% and a mean reduction in TE flow capacity of ‒4.87%. These average values are presented in Table 4. The difference in the mean reduction in film hole coolant capacity between the three selected vanes of set 1 (‒5.15%) and the parent set of 12 vanes (‒2.20%) is attributed to the random nature of the deposition process (even within the same engine), and the small sample size. Likewise the mean reduction in TE slot coolant capacity between the three selected vanes (‒10.3%) and the parent set of 12 vanes (‒4.87%) is explained by the fact that only three vanes from the parent set have TE burn-back: i.e., in selecting the vanes to be studied in detail, vanes with more significant TE burn-back were preferred, and these had greater associated collapse of the TE slot than average across the parent set. Fig. 6 Fig. 6 Close modal Looking now at the data for set 2 (end-of-life parts) we see a reduction in coolant capacity between ‒6.27% and ‒5.43% for the film cooling holes (mean of ‒5.77% across three parts) and between ‒24.7% and ‒9.79% for the TE slot (mean of ‒16.8% across three parts). In contrast to the set 1 data, the decrease in coolant capacity of the film cooling holes appears to be primarily due to shrinkage of holes in the region of spalled TBC (spallation region shown in Fig. 1(b)), due to local over-heating of the part (similar effect to the TE slot collapse) This is shown in Fig. 6(d), marked C (LE of vane S2-V4). Interestingly, the effect is partially offset by enchained cracking between holes (marked D in Fig. 6(d)), leading to weeping flow through the cracks. As for set 1 parts, the decrease in TE flow for the set 2 parts is due to partial collapse of the TE slot. The radial extent of this was, on average, greater for the set 2 parts than the set 1 parts, on account of more severe TE overheating. This is consistent with greater radial extent of TE burn-back for the set 2 parts. Extreme burn-back (greater than the parts shown in the present study) would potentially lead to a reversing of this effect, due to an increase in slot width in the direction towards the LE of the vane. The impact of a change in film cooling flow capacity and TE flow capacity on aerodynamic loss will be considered in the next section. ### Local Kinetic Energy Loss Coefficient Distributions. Results of the downstream aerodynamic surveys are now considered. We defined a local KE loss coefficient ζ′(r, θ) by $ζ′(r,θ)=1−1−(p2(r,θ)p02(r,θ))χ1−(p2(r,θ)p01)χ$ (3) where χ = (γ − 1)/γ and γ is ratio of specific heats, p01 is the total pressure upstream of the vanes (assumed uniform), and p02(r, θ) and p2(r, θ) are the total and static pressures measured in the plane of interest downstream of the vanes. A discussion of this, and other performance metrics, is given in Ref. [23]. Figure 7 shows the local distributions of ζ′(r, θ) downstream of the mid-life vanes S1-V1 to S1-V4 (top row, frames ad respectively) and the end-of-life vanes S2-V1 to S2-V4 (bottom row, frames eh respectively). Flow turning is clockwise when viewed from downstream, and data are viewed from downstream. The distribution of ζ′(r, θ) is normalized by the maximum value of ζ′(r, θ) measured across all the data presented. Fig. 7 Fig. 7 Close modal Consider first the results for the new vanes, S1-V1 and S2-V1. There is a well-defined wake profile, which has a curve due to the compound lean in the aft region of the vane. The wake has a number of distinct maxima associated with regions of TE coolant ejection (for detailed analysis see [23]), which are intermittent on account of internal webs. The maximum value of ζ′(r, θ) in the wake is near the hub of the vane, where the vane exit Mach number is the highest. Compound lean and sweep in the vane geometry mean the traverse plane is closest to the TE at the hub, and furthest from the vane at mid-span. This is in accord with the result that the wake towards the hub is the least mixed (a second reason for the greatest peak value in this region), and the wake in the mid-span region is most mixed. Now consider the set 1 (mid-life) deteriorated vanes. Vanes S1-V2 and S1-V3 have only minor TE burn-back (see Fig. 1(a)), but the distortion to the downstream wake is significant. In the region of the TE damage, the wake is under-turned with respect to the undamaged vane, leading to turning of the passage flow away from the SS and towards the PS. The regions of under-turned flow (co-incident with the TE burn-back regions of Fig. 1(a)) are marked A and B in Figs. 7(b) and 7(c) respectively. Vane S1-V4 (Fig. 7(d)) did not exhibit TE burn-back and the wake is deeper than that of the reference vane (Fig. 7(a))—due to greater surface roughness—but of relatively similar form. All of the mid-life vanes assessed had greater profile loss than the undamaged vane, which was attributed to the increased surface roughness causing greater boundary layer loss (combination of earlier transition, but also greater growth rate within the turbulent boundary layer). The deteriorated set 2 (end-of-life) vanes have more significant TE burn-back (for extents see Fig. 1(b)), leading to gross disruption of the wake due to severe under-turning, and—in the case of S2-V2 and S2-V3—the formation of counter-rotating vortices (marked C and D in Fig. 7) either side of the more severe burnt-back regions (caused by strong radial gradient of whirl angle). Similar effects have been observed in Refs. [1517]. Between counter-rotating vortices, there are patches of low loss between the vortices, as the lossy flow is rolled-up into the vortex. The small cracks and bends at the TE of vane S2-V4 have caused a significant local broadening of the wake (marked E in Fig. 7). In the profile loss regions undisturbed by TE damage, the wake is thicker and deeper than the reference vane due to increased surface roughness of the part. We now examine the secondary flow regions in more detail. Local distributions of ζ′(r, θ) in the near-endwall regions are shown in Fig. 8. Secondary flow loss cores in the casing region (Figs. 8(a)8(h)) are difficult to identify for two reasons: they are less intense than at the hub due to the lower Mach number; there is downwash on the vane surface, spreading the boundary layer fluid throughout the wake (see e.g., [23]) and causing coalescence of the flow structures. In contrast to the casing data, in the near-hub region (Figs. 8(i)8(p)) the secondary loss cores are well-defined: for the reference vanes S1-V1 (Fig. 8(i)) and S2-V1 (Fig. 8(m)) the SS corner vortex and passage vortex are marked A and B respectively. For the corner vortex and passage vortex, the peak measured values of local normalized KE loss coefficient were approximately 80% and 66%, respectively, for both reference vanes. The radial locations of the peaks were 2% and 10% span fraction respectively. For all deteriorated vanes the secondary loss cores are both more intense and greater in size than for their corresponding reference vane. Fig. 8 Fig. 8 Close modal ### Plane-Average and Mixed-Out Kinetic Energy Loss Coefficient. In this section we consider both plane-average KE loss coefficients, and mixed-out KE loss coefficients for the vanes. The plane-average coefficient may be taken to represent the loss already manifested at the measurement plane. The mixed-out KE loss coefficient can be taken to represent the sum of the loss already manifested, and the unavoidable loss as the result of the mixing out of gradients already present within the flow (and unlikely to contribute usefully to work): i.e., the secondary kinetic energy (SKE) within the flow. Adopting the definitions of [23], we define the plane-average KE loss coefficient for a film-cooled vane by $ζ″″=1−(m˙m+m˙c)[1−(p2¯p02¯)χ]m˙m[1−(p2¯p01)χ]+m˙c[1−(p2¯p0c)χ]$ (4) where $m˙m$ and $m˙c$ are the mainstream and coolant mass flowrates, respectively, and $p02¯$ and $p2¯$ are the mass-flux-average total pressure and area-average static pressure, respectively. The mixed-out KE loss coefficient for a film-cooled vane is defined [23] by $ζ″″′=1−(m˙m+m˙c)[1−(p2¯′p02¯′)χ]m˙m[1−(p2¯′p01)χ]+m˙c[1−(p2¯′p0c)χ]$ (5) where $p02¯′$ and $p2¯′$ are the mixed-out total and static pressures, respectively, and where a prime is used to distinguish these mixed-out variables (result of mixing process) from averages resulting from the in-plane weighting (e.g., area, volume-flux, or mass-flux). The definition (5) is developed in Ref. [23], and the method for calculation of the mixed-out pressures ($p02¯′$ and $p2¯′$) is presented in Ref. [25] and summarized in Ref. [26]. As discussed, the residual SKE is defined as the difference between the mixed-out and plane-average KE loss coefficient $SKE=ζ″″′−ζ″″$ (6) Normalized plane-average $(ζ″″)$ and mixed-out $(ζ″″′)$ KE loss coefficients, and corresponding residual SKE values are summarized in Table 5. The data are normalized by the mixed-out KE loss coefficient of the reference vane within each set ($ζS1−V1″″′$ and $ζS2−V1″″′$). Table 5 Normalized plane-average KE loss coefficient, mixed-out KE loss coefficient, and residual SKE Set 1 vane$ζS1−VX″″ζS1−V1″″′$$ζS1−VX″″′ζS1−V1″″′$$SKES1−VXζS1−V1″″′$ S1-V10.651.000.35 S1-V20.771.120.35 S1-V30.731.070.34 S1-V40.741.080.34 Mean change S1-V(2–4)14.1%8.72%‒2.13% Mean change S1-V(2–12)13.6%7.81%‒2.57% Set 2 vane$ζS2−VX″″ζS2−V1″″′$$ζS2−VX″″ζS2−V1″″′$$SKES2−VXζS2−V1″″′$ S2-V10.651.000.35 S2-V20.861.330.47 S2-V30.721.120.40 S2-V40.771.110.34 Mean change S2-V(2–4)22.7%18.8%14.9% Set 1 vane$ζS1−VX″″ζS1−V1″″′$$ζS1−VX″″′ζS1−V1″″′$$SKES1−VXζS1−V1″″′$ S1-V10.651.000.35 S1-V20.771.120.35 S1-V30.731.070.34 S1-V40.741.080.34 Mean change S1-V(2–4)14.1%8.72%‒2.13% Mean change S1-V(2–12)13.6%7.81%‒2.57% Set 2 vane$ζS2−VX″″ζS2−V1″″′$$ζS2−VX″″ζS2−V1″″′$$SKES2−VXζS2−V1″″′$ S2-V10.651.000.35 S2-V20.861.330.47 S2-V30.721.120.40 S2-V40.771.110.34 Mean change S2-V(2–4)22.7%18.8%14.9% Consider first the data for set 1 (mid-life). For the reference vane, the normalized mixed-out KE loss coefficient is by definition unity. The normalized plane-average KE loss coefficient and SKE are 0.65 and 0.35 (sum to unity). The relatively large SKE (0.35 of the mixed-out loss) is accounted for by significant unmixed wake (traverse plane relatively close to TE). Now consider the set 1 deteriorated vanes. The average changes in $ζ″″$, $ζ″″′$, and SKE for vanes S1-V(2–4) were 14.1%, 8.72%, and ‒2.13%. Corresponding values for the full set of 12 vanes—vanes S1-V(2–12)—are extremely similar: 13.6%, 7.81%, and ‒2.57%, respectively. The vane-to-vane spread in data was very low, suggesting high similarity between parts. The increase in plane-average KE loss coefficient (average of 13.6% across all parts) is thought to be due simply to an increase in roughness, and associated boundary layer thickening. The SKE remains almost constant (average change of only ‒2.57%), which is explained by the fact that the flow structure is essentially unchanged (slight change in wake thickness). The corresponding average change in mixed-out loss is 7.81%. Looking at the data for set 2 (end-of-life), the reference vane, has normalized plane-average KE loss coefficient and SKE values of 0.65 and 0.35. These are identical to the values for set 1 parts, suggesting high consistency between sets. Looking at the set 2 deteriorated vanes (vanes S2-V(2–4)) we find the average increase (across three vanes) in $ζ″″$, $ζ″″′$, and SKE to be 22.7%, 18.8%, and 14.9%, respectively. The loss coefficients changes are significantly greater for set 2 than for set 1 both because of the flow-structure changes caused by severe TE burn-back, and the effects of increased surface roughness. The vane-to-vane spread in data is also higher that for set 1, on account of significant differences in the particular TE damage (see Fig. 1(b)). The increase in plane-average KE loss coefficient (average of 22.7% across all parts; approximately double that for set 1) is associated with both an increase in roughness and an increase in—already manifested—secondary flow loss at the mixing plane. In contrast to the set 1 data, the SKE change is significant (average change of 14.9%), and is caused by significant structural changes in the flow (see discussion above, noting—in particular—streamwise vortices marked C and D in Fig. 7) with the average dominated by the changes for vanes S2-V2 and S2-V3 (these have the most significant TE burn-back; see Fig. 1(b)), 34.3% and 14.3% respectively. The corresponding average change in mixed-out loss is 18.8%, approximately double that for set 1. So far as whole-life turbine performance modeling is concerned, we suggest preliminary (limited data sets) enhancement factors for mixed-out row loss of approximately 8% for mid-life parts, and 19% for end-of-life parts. Taking a typical mixed-out row total pressure loss of 6% [23] for new parts, these would translate to approximately −0.49% and −1.19% on row efficiency, respectively. For stage loss, an additional enhancement factor might be expected for the case of end-of-life parts (but not mid-life parts) on account of the extreme yaw angle variation in the vicinity of the TE burn-back, which would be expected to cause additional losses due to incidence variation in the rotor frame. We now consider the individual contributions of the change in film cooling flow capacity and TE slot flow capacity (due to in-service deterioration) on the overall change in aerodynamic loss. For this purpose we used the Hartsel [27] film cooling flow loss model and a TE slot flow loss model which we develop for our specific vane geometry and operating conditions. We first consider the film cooling loss model. This model is based on that of Hartsel [27], in which the flow is considered to be comprised of a mixing layer and mainstream layer, interacting at constant static pressure in the surface normal direction, but with the possibility of acceleration in the streamwise direction. Relative row capacities were calculated using nominal hole diameters, with a scaling factor (equivalent to a common discharge coefficient) chosen to match the overall coolant capacity of the model to that measured in the experiment. In the model individual rows exhaust to particular static pressures determined using CFD (see Burdett et al. [28] for more details). Changes in film cooling flow capacity due to deterioration were assumed to affect all film cooling holes uniformly. Using the model, we can calculate the predicted change in mixed-out KE loss coefficient (normalized by $ζS1−V1″″′$) as a function of a change in film cooling flow capacity: a so-called exchange rate between the two parameters. This function is shown in Fig. 9. We observe that a reduction of film cooling flow from the design condition leads to a reduction in overall loss. This trend was expected since in the Hartsel [27] model, the mixing loss (between the mainstream and the ejected coolant) is proportional to the coolant-to-mainstream mass flow ratio, which has reduced due to deterioration. If deterioration acts to reduce film capacity and increase roughness and TE damage, the reduced film loss acts to mitigate the increase in aerodynamic loss due to the increase surface roughness and TE burn-back. Fig. 9 Fig. 9 Close modal For the set 1 parts, the mean change in film cooling flow capacity was −2.20% (see Table 4), leading to a predicted change in mixed-out KE loss coefficient $ζ″″′$ of −0.91%. For the set 2 parts the mean change in film cooling flow capacity was −5.77% (see Table 4), leading to a predicted change in mixed-out KE loss coefficient $ζ″″′$ of ‒2.36%. It should be noted that the vanes in set 2 have heavily damaged LE with distorted film cooling holes and cracks (see Fig. 6(d)), and changes in the aerodynamics of the mixing process are beyond the scope of the model. We must regard the results for set 2 parts as therefore only indicative of likely trends rather than quantitatively robust. We now consider the TE slot flow loss model. The model is that presented in Burdett and Povey [29], based on earlier work by Stewart [30] and then Deckers and Denton [31]. The model uses a mass-momentum control volume method to determine the mixed-out loss coefficient for a particular TE geometry and TE slot mass flowrate. We assume that the change in TE slot flow capacity due to deterioration is uniform across the entire span of the slot, and represented by the measured change in TE slot flow capacity. The predicted change in mixed-out KE loss coefficient (normalized by $ζS1−V1″″′$) as a function of the change in TE slot flow capacity is shown in Fig. 9. We observe that a reduction of TE slot flow from the design condition leads to an increase in overall loss. Deckers and Denton [31] showed that at a given coolant ejection pressure ratio, an increase in coolant TE slot flow capacity increases the base region pressure of an airfoil, and thus reduces the mixed-out KE loss coefficient (lower pressure drag) of the vane. The mean changes in TE slot flow capacity for set 1 and 2 parts (see Table 4) were −4.87% and −16.8% respectively, leading to predicted increases in mixed-out KE loss coefficient $(ζ″″′)$ of 2.18% and 7.62%, respectively. For our deteriorated parts both the film capacity and TE slot flow capacity are reduced, but the modeled changes in KE loss coefficient are in opposite directions. Taking the results of these models in combination with the measured overall change in mixed-out KE loss coefficient with deterioration (Table 5), we can estimate the change in mixed-out loss attributable to aerodynamic changes not included in the loss models. That is, effects such as: boundary layer changes caused by surface roughness and spalling; changes in secondary flow behavior caused by TE burn-back; and additional loss introduced at the point of coolant injection not captured in the basic model. The estimated values for additional aerodynamic loss were 6.54% and 13.5% for set 1 and set 2 parts, respectively. The measured overall loss (Table 5) and the predicted (loss models) and inferred (by difference) contributions are represented diagrammatically in Fig. 10. Fig. 10 Fig. 10 Close modal ### Circumferential Profiles of Local Kinetic Energy Loss Coefficient. We now consider the circumferential profiles of local KE loss coefficient, ζ′(θ), downstream of the vanes. Figures 11 and 12 show the circumferential profiles of ζ′(θ) at 10%, 50%, and 90% span downstream of vanes of set 1 (S1-V1 to S1-V4) and set 2 (S2-V1 to S2-V4), respectively. Each profile is radially averaged over ±5% at the relevant span location, and is circumferentially centered at its peak value. The distributions ζ′(θ) are normalized by the maximum value of ζ′(r, θ) measured across all the data presented. Fig. 11 Fig. 11 Close modal Fig. 12 Fig. 12 Close modal First consider the reference vanes: S1-V1 in Fig. 11, and S2-V1 in Fig. 12. As expected, the wake profiles have a quasi-normal distribution. The wake profiles at 10% span are narrower and have a greater peak value of ζ′(θ) than at 50% and 90% span. This is primarily due to spanwise variation of the TE position with respect to the traverse plane (see earlier discussion). The gradient of ζ′(θ) is slightly greater moving away from the SS than the PS. This is thought to be due to differences in the circumferential distributions of the separation loss contribution to overall loss, arising due to greater TE thickness on the PS than on the SS (design is of SS TE overhang style; see, for example, [29]). This effect opposes, and is thought to be more dominant than, the significantly larger boundary layer momentum thickness on the SS at the TE (for further discussion see [23,29]). Now consider wake profiles for the deteriorated vanes of set 1: lines S1-V2 to S1-V4 in Fig. 11. In general, the ζ′(θ) profiles show higher peak loss, but with a similar profile shape as the undeteriorated vane. As discussed, this is due to greater profile loss and greater boundary layer thickening on account of the greater surface roughness. We characterize the circumferential profiles with three metrics: peak height (method of Burdett and Povey [23]); peak width (method of [23]); and integrated loss (IL) defined by $IL=∫−0.50.5ζ′(θ)/ζmax′dθ$ (7) Values for these metrics evaluated at 50% span are presented in Table 6, both for the three deteriorated vanes of Fig. 11, and for the parent set of 12 vanes. Taking an average across all 12 vanes, the mean changes in peak height, peak width, and integrated loss were 23.9%, ‒1.67%, and 29.8% respectively. That is, there is a substantial increase in overall loss, but relatively little thickening of the wake. This is because the wake width at the traverse plane is dominated by the width of the separated TE region (or base region), as opposed to the boundary layer thickness (more details in Ref. [23]), into which both the boundary layer loss and so-called pressure drag of the base region are subsumed. Table 6 Metrics for wake characterization for set 1 (mid-life) and set 2 (end-of-life) vanes at 50% span Vane$(ζ′/ζmax′)peak$Peak widthIL S1-V10.2990.2250.0763 S1-V20.3480.2460.1071 S1-V30.3760.2230.0967 S1-V40.3750.2020.0952 Mean change S1-V(2–4)22.5%‒0.64%30.3% Mean change S1-V(2–12)23.9%‒1.67%29.8% S2-V10.2830.2450.0940 S2-V20.4880.2790.1521 S2-V30.2970.2030.0748 S2-V40.4610.2370.1244 Mean change S2-V(2–4)46.7%‒1.99%24.5% Vane$(ζ′/ζmax′)peak$Peak widthIL S1-V10.2990.2250.0763 S1-V20.3480.2460.1071 S1-V30.3760.2230.0967 S1-V40.3750.2020.0952 Mean change S1-V(2–4)22.5%‒0.64%30.3% Mean change S1-V(2–12)23.9%‒1.67%29.8% S2-V10.2830.2450.0940 S2-V20.4880.2790.1521 S2-V30.2970.2030.0748 S2-V40.4610.2370.1244 Mean change S2-V(2–4)46.7%‒1.99%24.5% Based on this statistically meaningful set of vanes (12 in total) we conclude that mid-life vanes can be characterized by a loss increase of approximately 30%, with no substantial change in the wake width (rotor forcing implications) or profile shape. These numbers could be used in preliminary design for whole-life modeling. Now consider the wake profiles for the deteriorated set 2 (end-of-life) vanes. For this set, the wake profile shapes for the deteriorated vanes differ from the reference vane by more than for the set 1 comparisons, on account of significant vortex activity associated with strong radial whirl angle variation in the regions of the TE burn-back. At the traverse plane, these secondary flows affect all span locations, but with a significant impact at midspan (where the burn-back is most severe). This leads to more local variation in the wake depth and width than for parts without TE burn-back. For all the three tested deteriorated vanes at all span locations, there was an increase in peak height, with the greatest increases in peak height being substantially larger than for the set 1 parts. That is, the peak loss was greater, but there was more randomness in the profile due to significant secondary flow activity. The mean changes (across three vanes) in peak height, peak width, and integrated loss were 46.7%, ‒1.99%, and 24.5% respectively. These are summarized in Table 6. Based on the relatively small sample (three parts) we conclude that end-of-life vanes can be characterized by a loss increases in the range ‒20.4–61.8% (relatively low confidence due to small statistical set). There is significant part-to-part variability in the integrated loss, but also in the radial distribution of loss, the wake shape, and the associated secondary flow, leading to greater variability in the downstream rotor inlet flow. ### Midspan Profile Total Pressure Loss: Comparison With the Study of Erickson et al. In this section we perform a detailed comparison of the measured changes in midspan profile total pressure loss—with increased surface roughness—to the results of study of Erickson et al. [12]. We consider this useful because of the high degree of similarity between the experiments. Erickson et al. tested two configurations: a reference cascade configuration in which the airfoil surface (PS and SS) has an aerodynamically smooth surface (roughness height not reported); and a rough cascade configuration in which the entire PS and the first 10% of the SS had a surface profile designed to simulate in-service roughening (the remaining SS had the same surface finish as the reference case). The reported ks/C for the roughened surface was 0.98 × 10−3, using the same reporting methodology as the present study [19]. For the comparison we consider only two vanes: the reference vane for set 1 (S1-V1); and vane S1-V10, which has no TE burn-back, and minimal changes in film cooling flow capacity and TE slot flow capacity (‒0.31% and ‒1.21% respectively). These vanes were chosen to isolate the effect of roughness without conflating it with effects due to other deterioration features. For part S1-V10, average values of roughness were ks/C = 1.02 × 10−3 for the PS and early SS, and ks/C = 0.29 × 10−3 for the rest of the SS. These values were very similar to those in the Erickson et al. [12] study. Table 7 compares the two studies in terms of: experimental facility; operating conditions; details of tested components including roughness. The primary difference between the studies was unmatched exit Mach number (0.05–0.20 for Erickson et al. versus 0.92 for the present study). Table 7 Comparison of facility details, operating conditions, and tested components between the present study and Erickson et al. [12] ParameterErickson et al. [12]Present study Film coolingNoYes Axial distance of measurement plane downstream of vane TE0.25 Cax0.25 Cax Mean vane isentropic exit Mach no., M2,is0.05–0.200.92 Exit Reynolds no., ReC0.50 × 106–2.00 × 1061.60 × 106 Vane inlet turbulence intensity, Tu0.70–13.5%12% Equivalent sandgrain roughness height calculation methodBons [19]Bons [19] Reference configuration Average equivalent sandgrain roughness height all around airfoil, ks/CNot reported0.11 × 10−3 Rough configuration PS surface distance significantly roughened0–100%0–100% SS surface distance significantly roughened0–10%0–15% Rough surface typeEngine-representativeEngine-representative Average equivalent sandgrain roughness height on PS and early SS, ks/C0.98 × 10−31.02 × 10−3 Average equivalent sandgrain roughness height on the rest of SS, ks/CNot reported0.29 × 10−3 ParameterErickson et al. [12]Present study Film coolingNoYes Axial distance of measurement plane downstream of vane TE0.25 Cax0.25 Cax Mean vane isentropic exit Mach no., M2,is0.05–0.200.92 Exit Reynolds no., ReC0.50 × 106–2.00 × 1061.60 × 106 Vane inlet turbulence intensity, Tu0.70–13.5%12% Equivalent sandgrain roughness height calculation methodBons [19]Bons [19] Reference configuration Average equivalent sandgrain roughness height all around airfoil, ks/CNot reported0.11 × 10−3 Rough configuration PS surface distance significantly roughened0–100%0–100% SS surface distance significantly roughened0–10%0–15% Rough surface typeEngine-representativeEngine-representative Average equivalent sandgrain roughness height on PS and early SS, ks/C0.98 × 10−31.02 × 10−3 Average equivalent sandgrain roughness height on the rest of SS, ks/CNot reported0.29 × 10−3 We compare aerodynamic loss data using the metric of Erickson et al. [12]: a plane-average mid-span profile loss coefficient defined by $Yp=p01−p02¯p01−p2¯$ (8) in which $p02¯$ and $p2¯$ are the plane-average total and static pressures based on data in the 45–55% span region. The method of calculation of the plane-average pressures ($p02¯$ and $p2¯$) is presented in Ref. [26]. For an extended discussion of relative merits of different loss coefficients see [32]. Comparison of plane-average instead of mixed-out loss coefficients is thought to be acceptable in this environment since the measurement plane for both studies is located at the same normalized axial distance from the vane TE (i.e., 0.25 Cax), and therefore the result is less subject to traverse plane specification (see further discussion in Ref. [32]). Figure 13 shows a comparison between the change in Yp (due to increased surface roughness) reported by Erickson et al. and reported in the present study. In the present study an increase in Yp (from reference vane S1-V1) of 12.2% was measured, for Tu = 12%. Linearly interpolating the Erickson et al. data (between Tu = 8.50% and Tu = 13.5%, and between Re = 1.0 × 106 and Re = 2.0 × 106) gives an increase in Yp of 15.2%. Fig. 13 Fig. 13 Close modal We take these results to be in good agreement, with the discrepancy potentially arising due to higher non-dimensional roughness for our reference (ks/C = 0.11 × 10−3) than the vane used in the Erickson et al. study (reported to be aerodynamically smooth, defined by ks/C < 100/ReC, i.e., ks/C < 0.05 × 10−3). That is, we would expect our reference vane loss to be slightly higher than in the Erickson et al. study. We conclude the following: agreement between the results can be taken as evidence of cross-validation; from a whole-life modeling perspective, we propose profile loss enhancement factors in the range 12.2% to 15.2% for mid-life nozzle guide vanes with ks/C ∼ 1.00 × 10−3 on the PS and early SS, where the lower end of the range can be taken for parts with TBC coating, and the upper end for parts which are initially aerodynamically smooth. ### Radial Distributions of Flow Angle. We now consider radial flow-angle distributions downstream of the vanes. Pitch and yaw angles (α2 and β2, respectively) are defined in Fig. 14. Fig. 14 Fig. 14 Close modal Spanwise distributions of circumferentially mass-flux-average flow angle (pitch angle, $α¯2$, and yaw angle, $β¯2$) downstream of vanes in set 1 (S1-V1 to S1-V4) and set 2 (S2-V1 to S2-V4) are presented in Figs. 15 and 16 respectively. Fig. 15 Fig. 15 Close modal Fig. 16 Fig. 16 Close modal First consider the pitch angle results for the set 1 (mid-life) vanes (Fig. 15). Radial distributions of pitch angle, $α¯2$, are shown in Fig. 15(a). For the reference vane (S1-V1) pitch angle is small and positive and decreases slowly with increasing radius. This is thought to be due to the more prominent annulus hade at the hub than the case. That is, an overall annulus contraction, dominated by the hub annulus line hade (see Fig. 2). The pitch angle trend is approximately linear with radius, varying between 1.9 deg < $α¯2$ < 5.3 deg. The mid-life vanes (S1-V2 to S1-V4) have the following characteristic differences from the reference vane: slightly greater mean pitch angle (by 0.2 deg on average); slightly lower spanwise variation (by ‒1.1 deg per unit of span on average); and slightly greater local variability from a linear trend (mean RMS variation of 0.5 deg from a linear trend compared to 0.4 deg for the reference vane). The small increase in both mean pitch angle and radial variation of pitch angle are not thought to arise from deterioration effects, but rather are thought to be due to quasi-random variation in the manufacturing of the vanes. The increased local variation is thought to arise from increased secondary flow activity, associated with surface defects, increased boundary layer thickness (and associated intensification of vortex features), and TE notching. Vane S1-V3 has the largest region of TE burn-back (see Fig. 1(a)), and this is clearly associated with a local deviation in $α¯2$. This is marked A in Fig. 15(a). The estimated value of Δ$α¯2$ (deviation from a locally linear trend for the particular vane) is Δ$α¯2$ = ‒0.7 deg. Now consider radial yaw angle distribution for the mid-life vanes (Fig. 15(b)). Looking at the reference vane, yaw angle increases with radius according to the particular forced vortex design of the vane, varying approximately linearly between 74.1 deg $<β¯2<$ 80.3 deg. The effect of deterioration (S1-V2 to S1-V4) is threefold: to very slightly decrease the mean yaw angle (by 0.5 deg on average); to cause slightly more local variation in hub and case secondary flow regions (2–10% span; 90–98% span); and to cause strong local deviations in regions of TE burn-back. An example of this last effect is marked B in Fig. 15(b), for which the deviation from the locally linear trend for the particular vane was approximately $Δβ¯2$ = ‒1.9 deg. Now consider the corresponding results for the set 2 (end-of-life) vanes. The flow angle distributions downstream of the baseline vane (S2-V2) have similar trends to the baseline vane of set 1 (S1-V1). The aerodynamic vane standard was essentially identical so this was expected. For the deteriorated vanes, in regions of severe TE burn-back (see Fig. 1(b)) there are significant variations in both pitch and yaw angles. The yaw angle variation arises because of under turning in regions of burn-back (see, for example, features E and F in Fig. 16(b)). Pitch angle variation arises because of significant secondary flow associated with the strong shear (and associated secondary flow formation) at the edges of the burn-back regions (see, for example, features C and D in Fig. 16(a)). For the most severe burn-back (vane S2-V2) the local under turning (deviation from local trend) was estimated to be $Δβ¯2$ = ‒6.1 deg. The corresponding variation in local pitch angle was estimated to be $Δα¯2$ = ‒1.8 deg. We now consider the relationship between maximum yaw angle deviation, $(Δβ¯2)max$, measured downstream of a particular burn-back feature, and the corresponding maximum depth of TE burn-back feature, Dmax/C. Three data points from set 1 parts (mid-life) and three data points from set 2 parts (end-of-life) are presented in Fig. 17. The data for both sets of parts were well-correlated with a linear trend of form $(Δβ¯2)max=−47Dmax/C$ (9) Fig. 17 Fig. 17 Close modal The trend was constrained to go through the origin for obvious physical reasons. A slightly better fit of set 1 data than set 2 data, and a slightly higher gradient for set 2 data than set 1 data (when individually fitted, not shown) may be explained by the greater radial extent of set 2 burn-back features, leading to less diminution of the yaw angle deviation effect in the intermediate mixing process (between vane TE and measurement plane). The empirical correlation (9) is proposed for preliminary whole-life performance assessment. The correlation would be improved with further experimental data taking separate account of both burn-back depth and radial extent. ## Conclusions In this paper, 15 real-engine in-service-deteriorated HP NGVs with a broad variety of deterioration features were studied for the purpose of describing and quantifying their aerodynamic performance, as a step towards whole-life engine modeling. The deterioration features included increased surface roughness; thermal barrier coating spallation; damaged film cooling holes; and trailing edge burn-back. The study was split into six areas, from which the following conclusions were drawn: 1. Surface roughness. In-service roughening was found to primarily affect the PS and early SS, but not the late SS. For vanes initially coated with TBC, typical mean equivalent sandgrain roughness height was found to increase on the PS and early SS from ks/C = 0.109 × 10−3 for new vanes, to ks/C = 0.590 × 10−3 and ks/C = 0.222 × 10−3 for mid-life and end-of-life vanes, respectively. These are increases of 441% and 104%—on average—for mid-life and end-of-life vanes in this study. 2. Coolant flow capacity. Coolant flow capacity decreased with service time both due to accumulation of deposits in the film cooling holes, and partial collapse of film cooling holes and TE slots due to overheating. For mid-life vanes, the mean change in coolant capacity was ‒2.20% for the film cooling holes and ‒4.87% for the TE slots. Corresponding values for end-of-life vanes were ‒5.77% and ‒16.8% respectively. 3. Overall aerodynamic loss. In-service deterioration was found to increase aerodynamic loss. The overall mean enhancement for mixed-out row KE loss was found to be approximately 8% for mid-life vanes, and 19% for end-of-life vanes. We propose these enhancement factors as rules of thumb for whole-life engine modeling. Mechanisms for increased mixed-out loss include: boundary layer thickening on the vane surface and endwalls due to increased surface roughness, causing change in transition point, and change in rate of growth of the boundary layer; streamwise vortex generation (and associated higher residual SKE) in the downstream wake caused by TE burn-back leading to high gradients of yaw angle; reduction in TE slot flow leading to increased base loss. In addition to these effects it is believed that the reduced cooling flow reduces loss, partly mitigating these increases (but leading to excessive part temperature). 4. Separated loss components. Using film cooling and TE slot loss models we show that of the 7.81% and 18.8% loss enhancements associated with mid-life and end-of-life deterioration, changes of ‒0.91% and ‒2.36% can be attributed to reduced film cooling flow (reduced loss), and 2.18% and 7.62% can be attributed to reduced TE flow (increased loss). The remaining 6.54% and 13.5%, respectively, are attributable to aerodynamic changes not included in the loss models, for example: boundary layer changes caused by surface roughness and spalling; changes in secondary flow behavior caused by TE burn-back; and additional loss introduced at the point of coolant injection not captured in the basic model. 5. Profile loss for undamaged mid-life parts. Taking the results of the present study, and the study of Erickson et al. [12] together, we conclude that in-service deterioration increase profile loss of mid-life undamaged parts with ks/C ∼ 1.00 × 10−3 on their PS and early SS by between 12.2% and 15.2%, where the lower value corresponds to parts initially TBC coated, and the upper value for parts which were initially aerodynamically smooth. 6. Downstream flow angles: TE burn-back was found to locally reduce downstream pitch and yaw flow angles. A simple empirical correlation between maximum yaw angle deviation and maximum TE burn-back depth was presented, and is proposed for preliminary whole-life performance assessment (stage modeling). This paper addresses a gap in literature, by providing the first detailed analysis of the overall impact of combined in-service deterioration features on the overall aerodynamic performance of HP NGVs. It is hoped that the results from this paper will be a useful step towards whole-life engine performance modeling and assessment. ## Acknowledgment The financial support of Rolls-Royce plc is gratefully acknowledged. Nafiz Chowdhury and Daniel Burdett are thanked for their support with the experiments. David Newman is thanked for his support with the coolant capacity measurements and technical advice. The Laboratory for In-situ Microscopy and Analysis (LIMA) at the University of Oxford is also thanked for support of the surface roughness measurements. ## Conflict of Interest There are no conflicts of interest. ## Data Availability Statement The authors attest that all data for this study are included in the paper. ## Nomenclature ax = axial position, m C = tangential chord, m Cax = axial chord, m D = trailing edge damage depth, m Dmax = maximum trailing edge damage depth, m IL = integrated loss, – k = sandgrain roughness height, m ks = equivalent sandgrain roughness height, m $m˙$ = mass flowrate, kg/s M = Mach number, – p = static pressure, Pa p0 = total pressure, Pa $p¯$ = plane-average static pressure, Pa $p0¯$ = plane-average total pressure, Pa $p¯′$ = mixed-out static pressure, Pa $p0¯′$ = mixed-out total pressure, Pa r = ReC = exit Reynolds number based on tangential chord, – Rz = maximum peak-to-valley roughness height, m SKE = secondary kinetic energy, – T = static temperature, K T0 = total temperature, K Tu = inlet turbulence intensity, – x = streamwise distance, m y = spanwise distance, m Yp = plane-average total pressure loss coefficient, – z = wall-normal distance, m ## Greek Symbols α = pitch angle, ° $α¯$ = circumferentially mass-flux-average pitch angle, ° β = yaw angle, ° $β¯$ = circumferentially mass-flux-average yaw angle, ° γ = ratio of specific heat capacities, – Γ = capacity, kg/s K1/2/Pa ζ = kinetic energy loss coefficient, – ζ′ = local kinetic energy loss coefficient, – ζ″″ = plane-average kinetic energy loss coefficient, – ζ″″ = mixed-out kinetic energy loss coefficient, – θ = normalized (by vane pitch) circumferential position, – χ = (γ − 1)/γ, – ## Subscripts 1 = upstream of HP NGVs 2 = downstream of HP NGVs atm = atmospheric c = coolant is = isentropic ref = reference ## Acronyms CFD = computational fluid dynamics ECAT = Engine Component AeroThermal (facility) EXP = experiment HP = high pressure KE = kinetic energy LE = NGV = nozzle guide vane PS = pressure surface SS = suction surface TBC = thermal barrier coating TE = trailing edge TRL = ## References 1. 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https://openphysicsjournal.com/VOLUME/1/PAGE/28/FULLTEXT/	# Double Logarithms Resummation in Exclusive Processes: The Surprising Behavior of DVCS§ T. Altinoluk1, , B. Pire2, L. Szymanowski3, S. Wallon44 1 Departamento de Fisica de Particulas and IGFAE, Universidade de Santaigo de Compostela, E-15782 Santiago de Compostela, Galicia, Spain 2 CPhT, École Polytechnique, CNRS, F91128 Palaiseau, France 3 National Center for Nuclear Research (NCBJ), Warsaw, Poland 4 LPT, Université Paris-Sud, CNRS, 91405, Orsay, France & UPMC Univ. Paris 06, faculté de physique, 4 place Jussieu, 75252 Paris Cedex 05, France #### Article Metrics 0 ##### Total Statistics: Full-Text HTML Views: 1316 Abstract HTML Views: 546 ##### Unique Statistics: Full-Text HTML Views: 709 Abstract HTML Views: 359 open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited. Address correspondence to this author at the Departamento de Fisica de Particulas and IGFAE, Universidade de Santaigo de Compostela, E-15782 Santiago de Compostela, Galicia, Spain; Tel: + 34 881 813 984; Fax: +34 881 814 086; E-mail: [email protected] ## Abstract Double logarithms resummation has been much studied in inclusive as well as exclusive processes. The Sudakov mechanism has often be the crucial tool to exponentiate potentially large contributions to amplitudes or crosssections near phase-space boundaries. We report on a recent work where a very different pattern emerges : the DVCS quark coefficient function Cq (x,ξ) develops near the particular point x =ξ a non-alternate series in ${a}_{s}^{n}\text{}{\mathrm{log}}^{2n}\text{}\left(x–\xi \right)$ which may be resummed in a cosh $\left(k\sqrt{{a}_{s}}\right)\text{}\mathrm{log}\text{}\left(\left(x–\xi \right)\right)$ factor. This result is at odds with the known result for the corresponding coefficient function for the pion transition form factor near the end point Cq (z) although they are much related through a Cq(Z) correspondence. Keywords: Collinear gluon radiation, DVCS, quark coefficient function, resummation, semi-eikonal approximation, soft gluon radiation.. ## 1. INTRODUCTION While perturbative calculations are widely used in quantum field theory, their summation is always a formidable task, unreachable but in the simplest, not to say most simplistic, occurences. >From elementary particle to atomic and to solid state physics, resummation techniques have been developed to go beyond a fixed order perturbation estimate through the sampling and evaluation of an infinite class of diagrams shown to dominate in a limited kinematical region for some given observables. The result of such procedures is often an exponentiated factor as in the famous Sudakov case [1], exp(-Kg2log2z) where g is the coupling constant and z is the ratio of two different characteristic scales, which governs both QED and QCD calculations of exclusive form factors. As explained in detail in [2] we obtain for a specific case of exclusive scattering amplitude, namely the deeply virtual Compton scattering in the generalized cosh(kg log z) orken regime, a very different resummed result of the form cosh(kg log z) where z is a momentum fraction. To our knowledge, this form never previously emerged in field theoretic calculations. The process that we focus on is the most studied case of a class of reactions - exclusive hard hadronic processes - which are under intense experimental investigation. The result presented here provides an important stepping-stone for further developments enabling a consistent extraction of the quantities describing the 3-dimensional structure of the proton. In the collinear factorization framework the scattering amplitude for exclusive processes such as deeply virtual Compton scattering (DVCS) has been shown [3] to factorize in specific kinematical regions, provided a large scale controls the separation of short distance dominated partonic subprocesses and long distance hadronic matrix elements, the generalized parton distributions (GPDs) [4]. The amplitude for the DVCS process ${y}^{}{\left(q\right)}^{N}\left(p\right)\text{}\to y{\left({q}^{\text{'}}\right)}^{{N}^{\text{'}}}\left({p}^{\text{'}}\right)$ with a large virtuality q2=-Q2, factorizes in terms of perturbatively calculable coefficient functions $C\left(x,\xi ,{\alpha }_{s}\right)$ and GPDs H(x,ξ,t), where the scaling variable in the generalized Bjorken limit is the skewness ξ defined as $\xi =\frac{{Q}^{2}}{\left(p+{p}^{\text{'}}\right).\left(q+{q}^{\text{'}}\right)}.$The calculation of first order perturbative corrections to the partonic amplitude has shown that terms of order $\frac{{\mathrm{log}}^{2}\left(x±\xi \right)}{x±\xi }$ play an important role in the region of small (x±ξ) i.e. in the vicinity of the boundary between the domains where the QCD evolution equations of GPDs take distinct forms (the so-called ERBL and DGLAP domains). We scrutinize these regions and demonstrate that they are dominated by soft fermion and gluon propagation. This explains why they can be exponentiated using quasi-eikonal techniques. ## 2. MAIN STEPS OF OUR ANALYSIS To set up our notations, let us remind the reader of the known results for the NLO corrections to the DVCS amplitude (1), specializing to the quark contribution to its symmetric part. After proper renormalization, it reads ${A}^{µv}\text{}=\text{}{g}_{T}^{µv}\text{}{\int }_{–1}^{1}\mathrm{dx}\text{}\left(\left(\sum _{q}^{{n}_{F}}{T}^{q}\left(x\right){H}^{q}\left(x,\xi ,t\right)\right)\right),$ where the quark coefficient function Tq reads [5] (3) ${T}^{q}={C}_{0}^{q}+{C}_{1}^{q}+{C}_{\mathrm{coll}}^{q}\mathrm{log}\frac{\left({Q}^{2}\right)}{{}_{F}^{2}},$ ${C}_{0}^{q}={e}_{q}^{2}\left(\left(\frac{1}{x–\xi +i\epsilon }–x\to –x\right)\right),$ (5) ${C}_{1}^{q}=\frac{{e}_{q}^{2}{}_{s}{C}_{F}}{4\left(x+i\right)}\left({\mathrm{log}}^{2}\left(\frac{x}{2}i\right)93\frac{x}{+x}\mathrm{log}\left(\frac{x}{2}i\right)\right)\left(xx\right).$ The first (resp. second) terms in Eqs. (4) and (5) correspond to the s-channel (resp. u-channel) class of diagrams. One goes from the s-channel to the u-channel by the interchange of the photon attachments. Since these two contributions are obtained from one another by a simple (x↔-x) interchange, we now restrict mostly to the discussion of the former class of diagrams. Let us first point out that in the same spirit as for evolution equations, the extraction of the soft-collinear singularities which dominate the amplitude in the limit x → ± ξ is made easier if one uses the light-like gauge p1. A = 0 with p1 = q' We argue (and verified) that in this gauge the amplitude is dominated by ladder-like diagrams. We expand any momentum in the Sudakov basis p1p2, as $k=\alpha {p}_{1}+\beta {p}_{2}+{k}_{}$ where p2 is the light-cone direction of the two incoming and outgoing partons $\left({p}_{1}^{2}={p}_{2}^{2}=0,2{p}_{1}.\text{}{p}_{2}=s={Q}^{2}2\xi \right)$. In this basis, ${q}_{\stackrel{\text{∗}}{y}}={p}_{1}–2\text{}\xi {p}_{2}.$. We now restrict our study to the limit x → + ξ . The dominant kinematics is given by a strong ordering both in longitudinal and transverse momenta, according to (see Fig. 1) : $x\xi \left(\left(\beta \right)\left(\right)x–\left(\xi \right)\left(\right)x–\xi +\left({\beta }_{1}\right)\left(\right)\left({\beta }_{2}\right)...\right)$ $...\left(x–\xi +{\beta }_{1}+{\beta }_{2}+...+{\beta }_{n–1}\left(\right)\left({\beta }_{n}\right),\right)$ $\left({k}_{1}^{2}\left(\left({k}_{n}^{2}\left(s\text{}{Q}^{2}\right)\right)\right)\right)$ $\left({a}_{1}\left(...\left({a}_{n}\left(1.\right)\right)\right)\right)$ This ordering is related to the fact that the dominant double logarithmic contribution for each loop arises from the region of phase space where both soft and collinear singularities manifest themselves. When x→ξ the left fermionic line is a hard line, from which the gluons are emitted in an eikonal way (which means that these gluons have their all four-components neglected in the vertex w.r.t. the momentum of the emitter), with an ordering in p2 direction and a collinear ordering. For the right fermionic line, eikonal approximation is not valid, since the dominant momentum flow along p2 is from gluon to fermion, nevertheless the collinear approximation can still be applied. When computing the coefficient functions, one faces both UV and IR divergencies. On the one hand, the UV divergencies are taken care of through renormalization, which manifest themselves by a renormalization scale µR dependency. On the other hand, the IR divergencies remain, but factorization proofs at any order for DVCS justify the fact that they can be absorbed inside the generalized parton distributions and result in finite coefficient functions. In our study, we are only interested into finite parts. Thus, using dimensional regularization, in a factorization scheme like $\stackrel{}{\mathrm{MS}}$, any scaleless integral can be safely put to zero although it contains both UV and IR divergencies. Following this line of thought, we can thus safely deal with DVCS on a quark for our resummation purpose. Finally, the issue related to the iε prescription in Eq. (5) is solved by computing the coefficient function in the unphysical region ξ > 1. After analytical continuation to the physical region 0≤ ξ ≤ 1, the final result is then obtained through the shift ξ→ξ-iε. We define Kn as the contribution of a n-loop ladder to the coefficient function. Let us sketch the main steps of the derivation of K1 and then generalize it for Kn. ### 2.1. The Ladder Diagram at Order αs A careful analysis [2] shows that among the one loop diagrams and in the light-like axial gauge p1.A=0, the box diagram is dominant for x→ξ. Starting from the dominant part of the numerator of the Born term which is θ=-2p1, the numerator of the box diagram is $\mathrm{tr}\left({p}_{2}{y}^{µ}\left(k+\left(x–\xi \right)\left({p}_{2}\right)\left(k+\right)\right)\left(x+\xi \right)\left({p}_{2}\right)\left({y}^{v}\right){d}^{µv}.\right)$ In the limit x → ξ, while the left fermionic line is hard with a large p2 momentum, the gluonic line is soft with respect to the left fermionic line. So we perform soft gluon approximation in the numerator by taking $k+\left(x+\xi \right){p}_{2}\to \left(x+\xi \right){p}_{2}.$. The dominant contribution comes from the residue of the gluonic propagator. Thus, the numerator of the on-shell gluon propagator, dµv, is expressed in terms of transverse polarizations, i.e. ${d}^{µv\text{}}–{\sum }_{}{}_{\left(\right)}^{µ}\text{}{}_{\left(\right)}^{v}$ Writing the gluon polarization vectors in the light-like P1.A=0 gauge through their Sudakov decomposition 10 ${}_{\left(\right)}^{µ}={}_{\left(\right)}^{µ}–2\text{}\frac{{}_{\left(\right).\text{}{k}_{}}}{\beta s}{p}_{1}^{µ}$ (10) allows us to define an effective vertex for the gluon and outgoing quark through the polarization sum 11 $\sum _{}{}_{\left(\right).\text{}}{k}_{}{}_{\left(\right)}^{µ}\text{}=\text{}–\text{}{k}_{}^{µ}+2\text{}\frac{{k}_{}^{2}}{\beta s}{p}_{1}^{µ}$ The numerator, (Num)1, is α - independent and reads $\frac{–4\left(x+\xi \right)}{\beta }\mathrm{tr}\left(\left({p}_{2}\left({k}_{}–2\right)\text{}\frac{{k}_{}^{2}}{\beta s}\left({p}_{1}\right)\left(k+\left(x–\xi \right)\left({p}_{2}\right){p}_{1}\right)\right)\right)$ 12 $=–4\text{}\left(x+\xi \right)s\text{}\frac{2{k}_{}^{2}}{\beta }\left(1+\frac{\left(x–\xi \right)}{\beta }\right)$ (12) We now calculate the integral over the gluon momentum k, using dimensional regularization $\int {d}^{d}\text{}k\to \frac{s}{2}\int d\alpha d\beta {d}^{d–2}\underset{}{k},$ , $\left({k}_{}^{2}={\underset{}{k}}^{2}\right)$ The Cauchy integration of the gluonic pole which gives the dominant contribution reads 13 $–2i\frac{s}{2}{\int }_{0}^{\xi –x}\frac{d\beta }{s\beta \text{}}{\int }_{0}^{}{d}^{d–2}\text{}\underset{–}{k}\text{}{\left(\frac{{\left(\mathrm{Num}\right)}_{1}}{{L}_{1}^{2}{R}_{1}^{2}{S}^{2}}\right)}_{\alpha =\frac{{k}^{2}}{{\beta }^{s}}}$ with the denominators ${L}_{1}^{2}=-{\underset{_}{k}}^{2}+\alpha \left(\beta +x+\xi \right)s$ , ${R}_{1}^{2}=-{\underset{_}{k}}^{2}+\alpha \left(\beta +x-\xi \right)s$ , ${S}^{2}=-{\underset{_}{k}}^{2}+\left(\beta +x-\xi \right)s$ and ${k}^{2}=-{\underset{_}{k}}^{2}+\alpha \beta s.$ The relevant region of integration corresponds to small $\|\beta +x-\xi \|$ . The β and $\underset{_}{k}$ integrations results in our final one-loop expression : 14 ${k}_{1\text{}}=\frac{i}{4}{e}_{q}^{2}\left(–{c}_{F}{\alpha }_{s}\frac{1}{{\left(2\right)}^{2}}\right)\frac{4}{x–\xi }\frac{2i}{2!}{\mathrm{log}}^{2}\left(a\left(x–\xi \right)\right),$ where we kept only the most singular terms in the x→ξ region and have no control of the value of a within our approximation. To fix a, we match our approximated one-loop result with the full one-loop result (5). This amounts to cut the ${\underset{_}{k}}^{2}$ integral at Q2. The ίε term is included according to the same matching. This leads to 15 ${k}_{1\text{}}=\frac{i}{4}{e}_{q}^{2}\left(–{c}_{F}{\alpha }_{s}\frac{1}{{\left(2\right)}^{2}}\right)\frac{4}{x–\xi +i}\frac{2i}{2!}{\mathrm{log}}^{2}\left(\frac{\xi –x}{2\xi }\text{}–i\right),\text{}$ (15) which is the known result. This is a positive test of the validity of our approximation procedure that we now generalize to the n-rung ladder. ### 2.2. The Ladder Diagram at Order ${\alpha }_{s}^{n}$ Let us now turn to the estimation of all ${log}^{2n}\left(x-\xi \right)$ terms in the diagram shown on Fig. (1). Assuming the strong ordering (7, 8) in K and α, the distribution of the poles generates nested integrals in βί as : Fig.(1). The ladder diagrams which contribute in the light-like gauge to the leading ${a}_{s}^{n}{1n}^{2n}\text{}\left(x\right)\left(x\right)$ terms in the perturbative expansion of the DVCS amplitude. The p2 and ᾕ momentum components are indicated. The dashed lines show the dominant momentum flows along the p2 direction. 16 ${\int }_{0}^{\xi –x}d{\beta }_{1}{\int }_{0}^{\xi –x–{\beta }_{1}}{d\beta }_{2}...{\int }_{0}^{\xi –x–{\beta }_{1}–..–{\beta }_{n–1}}d\text{}{\beta }_{n}$ The numerator for the nth order box diagram is obtained as: 17 ${\left(\mathrm{Num}\right)}_{2}=4s{\left(x+\xi \right)}^{n}\frac{2{k}_{1}^{2}}{{\beta }_{1}}\left(1+\left(\frac{2\left(x–\xi \right)}{{\beta }_{1}}\right)\frac{2{k}_{2}^{2}}{{\beta }_{2}}\text{}\left(1+\left(\frac{2\left({\beta }_{1}+x–\xi \right)}{{\beta }_{2}}\right)...\frac{{2k}_{n}^{2}}{{\beta }_{n}}\right)\text{}\left(1+\left(\frac{2\left({\beta }_{n–1}+...+{\beta }_{1}+x–\xi \right)}{{\beta }_{n}}\right)\right)\right)$ and the denominators of propagators are, for ί=1...n, 18 ${R}_{i}^{2}=–{\underset{}{k}}_{i}^{2}{\alpha }_{i}\left({\beta }_{1}\dots {\beta }_{i}x–\xi \right)s\text{},{S}^{2}=–{\underset{}{k}}_{n}^{2}\left({\beta }_{1}\dots {\beta }_{n}x–\xi \right)s\text{}.$ Using dimensional regularization and omitting scaleless integrals, the integral reads: 19 $\begin{array}{c}\text{}{\int }_{0}^{\xi –x}\text{}d{\beta }_{1}\text{}\dots \text{}{\int }_{0}^{\xi –x–\dots –{\beta }_{n–1}}\text{}d{\beta }_{n}\text{}{\int }_{0}^{}\text{}{d}^{d–2}{\underset{}{k}}_{n}\text{}\dots \text{}{\int }_{0}^{{\underset{}{k}}_{2}^{2}}\text{}{d}^{d–2}{\underset{}{k}}_{1}{\left(–1\right)}^{n}\\ \frac{4\text{}s{\left(2i\right)}^{n}}{x–\xi }\frac{1}{{\beta }_{1}x–\xi }\dots \frac{1}{{\beta }_{1}\text{}\text{}\dots \text{}\text{}{\beta }_{n–1}\text{}\text{}x\text{}–\text{}\xi }\\ \frac{1}{{\underset{}{k}}_{1}^{2}}\dots \frac{1}{{\underset{}{k}}_{n}^{2}}\frac{1}{{\underset{}{k}}_{n}^{2}–\left({\beta }_{1}\dots {\beta }_{n}x–\xi \right)s}\text{}\end{array}$ The integrals over ${\underset{_}{k}}_{1}\cdots {\underset{_}{k}}_{n}$ are performed similarly as in the one-loop case, resulting in: 20 ${k}_{n}=\frac{i}{4}{e}_{q}^{2}{\left(–i{C}_{F}{a}_{s}\frac{1}{{\left(2\right)}^{2}}\right)}^{n}\frac{4}{x–\xi +i}\frac{{\left(2i\right)}^{n}}{{\left(2n\right)}^{!}}{\mathrm{log}}^{2n}\left(\frac{\xi –x}{2\xi }–i\xi \right),$ where the matching condition introduced in one-loop case is extended to n-loops. ## 3. THE RESUMMED FORMULA Based on the results Eqs. (15, 20), one can build the resummed formula for the complete amplitude; we get with $D=\sqrt{\frac{{\alpha }_{s}{C}_{F}}{2}}$ 21 $\sum _{n=0}^{}{K}_{n}=\frac{{e}_{q}^{2}}{x–\xi i}cosh\left[Dlog\left(\frac{\xi –x}{2\xi }–i\right)\right]=\frac{1}{2}\frac{{e}_{q}^{2}}{x–\xi i}\left[{\left(\frac{\xi –x}{2\xi }–i\right)}^{D}{\left(\frac{\xi –x}{2\xi }–i\right)}^{–D}\right]\text{}.$ In the absence of a next to leading logarithmic calculation, the minimal and most natural resummed formula which has the same O(αs) expression as the full NLO result, reads, : 22 ${\left({C}_{0}{C}_{1}\right)}^{res}=\frac{{e}_{q}^{2}}{x–\xi i}&\mathrm{lcub};cosh\left[Dlog\left(\frac{\xi –x}{2\xi }–i\right)\right]–\frac{{D}^{2}}{2}\left[93\frac{\xi –x}{x\xi }log\left(\frac{\xi –x}{2\xi }–i\right)\right]&\mathrm{rcub};–\left(x–x\right)\text{}.$ ## 4. THE GLUON COEFFICIENT FUNCTION For several decades the effects of gluons on many high energy processes has been widely studied. Specifically the theory of "Color Glass Condensate" shows that at very high energies the behavior of the scattering amplitudes are dominated by gluons [6]. Recently it was also shown that even at moderate energies, there are significant O(αs) corrections to scattering amplitudes due to gluonic contributions for spacelike and timelike virtual Compton scatterings [7]. With the above mentioned motivations performing a similar resummation procedure for gluon coefficient function of DVCS and TCS would result in a more trustful extraction gluon GPDs. ### SUMMARY AND OUTLOOK We have demonstrated that resummation of soft-collinear gluon radiation effects can be performed in hard exclusive reactions amplitudes. The resulting formula for coefficient function stabilizes the perturbative expansion, which is crucial for a trustful extraction of GPDs from experimental data. A related expression should emerge in various reactions, such as the crossed case of timelike Compton scattering [8] and exclusive meson electroproduction. Giving these results, a question should be raised : what is the physics beyond this result, or in other words, why is the Sudakov resummation [9] familiar to experts of hard exclusive processes not applicable here? An even more precise question may be: how is our analysis compatible with the discussion of soft effects in the pion transition form factor, a quantity which has been much discussed [10] recently thanks to the experimental results of BABAR and BELLE? Let us stress that the coefficient function of this quantity is identical to the ERBL part of the coefficient function of the DVCS amplitude after a rescaling →x/ξ. Our result thus may be applied to the transition form factor. In [11], it has been argued that the ${\alpha }_{s}{log}^{2}\left(1–z\right)$ factor in the one loop expression of the coefficient function had to be understood as the sum of two very distinct terms, one of them exponentiating in a Sudakov form factor. To advocate this fact, the authors allow themselves an excursion outside the colinear factorization framework and use the familiar detour into the coordinate space framework. Our procedure is different and we resum the complete one loop result. In other words, one may ask to the authors of [11]: what happens to the remnant term proportional to ${\alpha }_{s}{log}^{2}\left(1–z\right)$ If indeed the usual resummation procedure of the transition pion form factor must be revised following our new results, one may ask whether the understanding of the meson form factor [12] should also be reconsidered. ## CONFLICT OF INTEREST The authors confirm that this article content has no conflict of interest. ## ACKNOWLEDGEMENTS We thank the organisors and the French CEA (IPhT and DSM) for support. This work is supported by the P2IO consortium, the Polish Grant NCN No. DEC-2011/01/B/ ST2/03915, the French grant grant ANR PARTONS (ANR-12-MONU-0008-01), the Joint Research Activity "Study of Strongly Interacting Matter" (HadronPhysics3, Grant Agree-ment no. 283286) under the 7th Framework Programme of the European Community, the European Research Council grant HotLHC ERC-2001- StG-279579, Ministerio de Ciencia e Innovac on of Spain grants FPA2009-06867-E, Consolider-Ingenio 2010 CPAN CSD2007-00042 and FEDER. ## REFERENCES [1] Sudakov VV. Vertex parts at very high-energies in quantum electrodynamics Sov Phys JETP 1956; 3: 65-71. [2] Altinoluk T, Pire B, Szymanowski L, Wallon S. Resumming soft and collinear contributions in deeply virtual Compton scattering JHEP 2012; 1210: 49-81. [3] (i) Müller D, Robaschik D, Geyer B, Dittes FM, Horesjsi J. Wave functions, evolution equations and evolution kernels from light ray operators of QCD ortsch Phys 1994; 42: 101-41.; (ii) Radyushkin AV. 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[11] Musatov IV, Radyushkin AV. Transverse momentum and Sudakov effects in exclusive QCD processes ????° form-factor Phys Rev D 1997; 56: 2713-35. [12] (i) Li HN, Sterman GF. The Perturbative pion form-factor with Sudakov suppression Nucl Phys B 1992; 381: 129-40.; (ii) Jakob R, Kroll P. The Pion form-factor Sudakov suppressions and intrinsic transverse momentum Phys Lett B 1993; 315: 463-70.; (iii) Gousset T, Pire B. Timelike form-factors at high-energy Phys Rev D 1995; 51: 15-24.; (iv) Stefanis NG, Schroers W, Kim HC. Analytic coupling and Sudakov effects in excluisve processes Pion and ?*???° form-factors Eur Phys J C 2000; 18: 137-56.; (iv) Braun VM, Khodjamirian A, Maul M. Pion form-factor in QCD at intermediate momentum transfers Phys Rev D 2000; 61: 73004-38.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 51, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8539682030677795, "perplexity": 4046.1051831067034}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-51/segments/1575540531974.7/warc/CC-MAIN-20191211160056-20191211184056-00169.warc.gz"}
https://www.thejournal.club/c/paper/276/	#### A variant of the Recoil Growth algorithm to generate multi-polymer systems ##### Florian Simatos The Recoil Growth algorithm, proposed in 1999 by Consta et al., is one of the most efficient algorithm available in the literature to sample from a multi-polymer system. Such problems are closely related to the generation of self-avoiding paths. In this paper, we study a variant of the original Recoil Growth algorithm, where we constrain the generation of a new polymer to take place on a specific class of graphs. This makes it possible to make a fine trade-off between computational cost and success rate. We moreover give a simple proof for a lower bound on the irreducibility of this new algorithm, which applies to the original algorithm as well. arrow_drop_up	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8532112240791321, "perplexity": 256.80968584853855}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-05/segments/1642320301263.50/warc/CC-MAIN-20220119033421-20220119063421-00629.warc.gz"}
https://homework.cpm.org/category/CC/textbook/CCA2/chapter/Ch4/lesson/4.2.2/problem/4-84	### Home > CCA2 > Chapter Ch4 > Lesson 4.2.2 > Problem4-84 4-84. Solve each of the following inequalities. Express the solutions algebraically and on a number line. 1. $3x-5\le7$ Solve the equation $3x-5\le7$ for $x$. Plot the boundary point on a number line. Test a point on each side of the boundary point. Shade the region that makes the inequality true. $x\le4$ 1. $x^2+6>42$ See part (a). This inequality is quadratic, so look for two boundary points. $x<−6$ or $x>6$	{"extraction_info": {"found_math": true, "script_math_tex": 7, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8730906844139099, "perplexity": 1216.7926409307502}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-25/segments/1623488539480.67/warc/CC-MAIN-20210623134306-20210623164306-00547.warc.gz"}
http://mathoverflow.net/questions/52931/point-on-a-line-nearest-a-point-in-banach-space/52939	# Point on a line nearest a point in Banach space I have a Banach space geometry question (a curiosity-driven spin-off from a research topic). Given a point $x$ on the unit sphere of a Banach space and a vector $y\ne 0$, there is a multiple $t_0y$ of $y$ for which $\\|t_0y-x\\|$ is minimized (this will be unique if the norm is strictly convex). My question is this: For which Banach spaces $X$ is it guaranteed that $\\|t_0y\\|\le \\|x\\|$? My "Euclidean intuition" suggested that this should be the case for all Banach spaces, but a little experimentation showed that this is not the case. You quickly see this is really a question about two dimensions. In fact it seems to fail for every $\ell^p$, $p\ne 2$ (see the attached figure in $p=1.2$). Could it be true that this property characterizes Hilbert space? (I looked at the obvious sources: (MO 11192 and papers mentioned in there and didn't find anything of the sort). - The answer is no in dimension 2 and yes in dimension 3 and higher. The property that the nearest-point projection to a line does not increase the norm is equivalent to the symmetry of orthogonality relation defined as follows: $x$ is orthogonal to $y$ iff $\\|x+ty\\|\ge\\|x\\|$ for all $t\in\mathbb R$. It is well-known that symmetry of this orthogonality relation in dimension $\ge 3$ implies that the norm is Euclidean, see e.g. Thompson's "Minkowski geometry", Theorem 3.4.10. This is not the case in dimension 2. There are many counter-examples (I believe they are called Radon planes). Basically you only need to ensure that every unit vector with its unit orthogonal one span a constant parallelogram area, this is easy to satisfy and is equivalent to the symmetry of orthogonality. For a simple explicit example (although non-smooth), consider a norm on the plane whose unit ball is a regular hexagon. - Thanks for the nice answer. Anthony – Anthony Quas Jan 23 '11 at 21:04	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9754469990730286, "perplexity": 107.4868497993688}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-10/segments/1394678697956/warc/CC-MAIN-20140313024457-00027-ip-10-183-142-35.ec2.internal.warc.gz"}
http://mathhelpforum.com/math-topics/62120-finding-primes.html	# Math Help - finding primes 1. ## finding primes How many primes are in the form 4n^8+1, where n is a positive integer? *show working n explanation, PLS... 2. Hello n=5p (where p is an integer) is a necessary condition but I do not know if it is a sufficient condition If n=5p+1 Then n^8=(5p+1)^8=5P+1 Therefore 4n^8+1=20P+5 is divisible by 5 => not prime If n=5p+2 Then n^8=(5p+2)^8=5P+2^8=5P+256 Therefore 4n^8+1=20P+1025 is divisible by 5 => not prime If n=5p+3 Then n^8=(5p+3)^8=5P+3^8=5P+6561 Therefore 4n^8+1=20P+26245 is divisible by 5 => not prime If n=5p+4 Then n^8=(5p+4)^8=5P+4^8=5P+65536 Therefore 4n^8+1=20P+262145 is divisible by 5 => not prime	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8903806209564209, "perplexity": 4120.89251225491}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-23/segments/1406510274967.3/warc/CC-MAIN-20140728011754-00199-ip-10-146-231-18.ec2.internal.warc.gz"}
https://socratic.org/questions/54d0432e581e2a17690a8838	Chemistry Topics # Question a8838 Feb 3, 2015 Since no information was given on the volume of the bottle, I'll do the calculations using a $\text{1-L}$ bottle. Moreover, you don't mention what the bottle is labeled as containing $\text{56.2 ppm}$. To be a little more specific, I don't know what's in the bottle to begin with. So, I'll show you how to determine the molarity of a solution that has $\text{56.2 ppm}$ of ${\text{Fe}}^{3 +}$ ions. What ppm - parts per million - means is that you have miligrams of solute in liter of solution. A $\text{1 ppm}$ solution would mean that you have $\text{1 ppm" = ("1 mg")/("1 L") = ("0.001 g")/("1000 mL}$ This means that a $\text{56.2 ppm}$ solution will have "56.2 ppm" = ("56.2 mg")/("1 L") = ("0.0562 g")/("1000 mL") In order to determine molarity you need moles of solute per volume of solution. Since you know that you have $\text{0.0562 g}$ of ${\text{Fe}}^{3 +}$ present, use iron's molar mass to determine how many moles you have ${\text{0.0562 g" * ("1 mole Fe"^(3+))/("55.85 g") = "0.00101 moles Fe}}^{3 +}$ This means that the solution's molarity is C = n/V = ("0.00101 moles")/("1 L") = "0.00101 mol/L" = "0.00101 M"# The molarity of the solution is so small that you can express it as $\text{mmol/L}$, or $\text{mM}$ (milimoles per liter, or milimolar) $C = \text{1.01 mmol/L" = "1.01 mM}$ ##### Impact of this question 564 views around the world	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 15, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7591279149055481, "perplexity": 1371.5494860170697}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-39/segments/1568514576345.90/warc/CC-MAIN-20190923084859-20190923110859-00261.warc.gz"}
https://ask.libreoffice.org/en/question/3960/select-multiple-entries-from-input-list-in-writer/	# Select multiple entries from input list in Writer [closed] edit I am creating a document to use as a template for medical notes. I want to be able to tab from input field to input field and make appropriate selections. In some cases it is possible that I would need to select more than one item from a list. Is there any way to make this happen? Thanks in advance. edit retag reopen merge delete ### Closed for the following reason the question is answered, right answer was accepted by Alex Kemp close date 2015-10-17 01:23:33.832507 Sort by » oldest newest most voted Yes, this is possible. The easiest way is to insert a ListBox and enable the "MultiSelect" option: • After inserting the ListBox, right-click on it to open the Context Menu: • Select "Control" to open the ListBox properties and set "Multiselect" to "Yes": Alternatively, you could use a set of checkboxes, but this works only if there only a few values to display and to select. For a longer list of values, you should choose a ListBox. ## EDIT: To populate the ListBox with Data, you will have to bind it to a Data Source. LibreOffice will ask for the DataSource when inserting the control. You can still add the required information using the "Data" tab of the control's properties: In this example, i've selected the "Bibliography" datasource (a LO Base Database that ships with LO) when i inserted the first form control. Then, i selected the "Author" field from the "biblio" table. If you didn't select a datasource yet, you can set the datasource later by selecting "´Form" from the control's context menu, tab "data`": more That's exactly what I'm looking for, unfortunately, it doesn't seem to work. When I add the ListBox and turn design mode off, I just get an empty rectangle with a non-functioning drop down triangle button. Any suggestions? ( 2012-07-18 18:23:51 +0100 )edit @Matt: I've emended my answer and added some info how to bind the control to a data source. ( 2012-07-18 18:58:36 +0100 )edit Thanks, that probably has gotten it to doe what it is supposed to do, but not exactly what I want it to do. I can select multiple entries from a list (although the ListBox must be big enough to see all entries, it doesn't make a true dropdown) but it just leaves those entries highlighted. ( 2012-07-18 19:25:05 +0100 )edit What I want to do is select entries and have only the selected entries displayed. ( 2012-07-18 19:25:26 +0100 )edit @Matt: So, if your list has entries A, B, C - you select A and C - then B should "disappear" from the list? I fear this isn't possible - maybe using a macro to modify the data source, but this would be quite complicated (what if the user wants to revise his selection?). ( 2012-07-18 21:04:22 +0100 )edit I am beginning to realize it is not possible in LibreOffice. Thanks for your help. Just to clarify though, theoretically the "list object" would exist in the document independent of what is displayed/printed. Thus selecting items from the list displays them but does not alter the list. ( 2012-07-18 22:31:51 +0100 )edit That would make revisions relatively easy. I have seen this functionality in software such as EPIC, but was not aware just how complex it must be. Thanks again for your assistance. ( 2012-07-18 22:32:46 +0100 )edit ## Stats Seen: 1,294 times Last updated: Jul 18 '12	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.18296006321907043, "perplexity": 1807.1408455814233}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-09/segments/1550247499009.48/warc/CC-MAIN-20190221031117-20190221053117-00424.warc.gz"}
https://cstheory.stackexchange.com/questions/22109/bsp-but-with-curved-surfaces-nurbs-kernelized-support-vectors	# BSP, but with curved surfaces (NURBS? kernelized support vectors?) Let's say that I wanted to use a BSP not just for partitioning points, but also to define surfaces, i.e. that I have $\mathbb{R}^2$ and I want to be able to continuously map at least some easily known/calculated continuous subset of it to the points on the surface at every branch. Let's furthermore say that I wanted those surfaces to be curved. I could arbitrarily approximate curved partitioning surfaces by using a helluva lot of straight planes ala the classic BSP, but that seems silly. Is there prior art in using NURBS or kernelized support vectors or whatever to define smooth curved surfaces in a binary space partitioning tree s.t. extraction of some of the boundaries' points from the representation (enough to illustrate the boundary) is easily (and preferably deterministically, avoiding monte carlo methods) accomplished? Or is this one of those trivial knowledge-synthesis problems and I'm better off just winging it? If not, could someone please point me in the right direction? • Life the point set to an appropriate manifold in higher dimension and do BSP in this space. The advantage is that you are dealing with hyperplanes in this lifted space. for example, if you wanted to use lines and circles, you would map a point $(x,y)$ to the lifted point $(x,y,x^2 + y^2)$. This is a standard trick in computational geometry (it is called lienarization - see here from relevant refs: sarielhp.org/p/01/fitting/fitting.pdf). – Sariel Har-Peled May 19 '16 at 1:28 You can absolutely do it with kernelized support vectors. I don't have a publication handy but I've implemented it myself before. You'll probably want to use quadrics for the split planes, and unfortunately I only found a suboptimal way to do csg (Naylor's original bsp/csg algorithm from 1990); there may be a better way. But it's very possible, and allows for a couple really interesting things: 1. ray segment/quadric bsp intersection tests can be done extremely effectively with the following procedure: first, early exit if the two points are not in the same node, then ray-march using the signed distance from the nearest quadric hyperplane, which is easy to compute by traversing the tree. This becomes very efficient, especially for certain smoother shapes, because the trees tend to be very shallow. 2. you can fit the hyperplanes to a sampling of a signed distance function by using linear least squares. Recursively split until all sample points are in the same node of the tree and the mean square error of the signed distance to the shape is below a certain tolerable level, at each stage using least squares to optimize the coefficients of the quadric split. 1. as implied in (1), determining whether one point is accessible from another reduces to determining whether they are in the same node of a very shallow tree, useful for 3d blob detection and such. As far as the implementation, it really is simple, as you have hinted. Just use a few more coefficients in the hyperplanar equation for each node, and the rest will flow. But if you want to look at my implementation, it's somewhere buried in my github (vpostman). Just lift the points to higher dimensions, and use BSP in the higher dimensional space. This is a standard techniuqe - see linearization (in section 3 here: http://sarielhp.org/p/04/survey/survey.pdf). For example, you map a point $(x,y)$ to the 3d point $(x,y,x^2+y^2)$. This lifts the points to a paraboloid in 3d. Now, any 3d plane corresponds a circle/line in the original plane. Thus, building the BSP on the lifted points, would correspond to hierarchial partition with circles and lines. Of course, this might completely ruin the query process on the points which you might try doing with the BSP.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5228767991065979, "perplexity": 393.456627844264}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-51/segments/1575540529955.67/warc/CC-MAIN-20191211045724-20191211073724-00110.warc.gz"}
http://www.ck12.org/geometry/Proofs-and-Use-of-the-Pythagorean-Theorem/enrichment/Pyramids-and-Pythagorean-Theorem-Example-1/	<img src="https://d5nxst8fruw4z.cloudfront.net/atrk.gif?account=iA1Pi1a8Dy00ym" style="display:none" height="1" width="1" alt="" /> # Proofs and Use of the Pythagorean Theorem ## Identify triples and calculate missing sides Estimated16 minsto complete % Progress Practice Proofs and Use of the Pythagorean Theorem Progress Estimated16 minsto complete % Pyramids and Pythagorean Theorem - Example 1 ### Explore More Sign in to explore more, including practice questions and solutions for Proofs and Use of the Pythagorean Theorem.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8767359852790833, "perplexity": 13589.117221642477}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-40/segments/1474738662541.24/warc/CC-MAIN-20160924173742-00064-ip-10-143-35-109.ec2.internal.warc.gz"}
https://www.physicsforums.com/threads/cumulative-distribution-and-density-functions.689221/	# Cumulative distribution and density functions 1. May 1, 2013 ### EngnrMatt 1. The problem statement, all variables and given/known data Let X be a random variable with probability density function: 0.048(5x-x2) IF 0 < x < 5 0 otherwise Find the cumulative distribution function of X a) If x ≤ 0, then F(x) = b) If 0 < x < 5, then F(x) = c) If x ≥ 5, then F(x) = 2. Relevant equations Not quite sure 3. The attempt at a solution The answer to a) is 0. The answer to c) is 1. I am making the reasonable assumption that a) is 0 because there is no probability at that point, and that c) is 1 because after that, all probability has been "used" so to speak. However, integrating the function between 0 and 5 does not work. It seems as if my professor totally skipped over teaching us this particular type of problem. Statistics usually makes a good deal of sense to me, but this is pretty foreign. 2. May 1, 2013 ### Ray Vickson You say "integrating the function between 0 and 5 does not work". What about it does not work? In fact, if we define f(x) = 0 for x < 0 and for x > 5, then the cumulative distribution F(z) is $$F(z) = \int_{-\infty}^z f(x) \, dx \\ = 0 \; \text{ if } z < 0,\\ = \int_0^z (48/1000)(5x - x^2) \, dx \; \text{ if } 0 \leq z \leq 5,\\ = 1 \; \text{ if } z > 5.$$ Do the integration to see what you get. Are you sure your course notes or textbook do not have any similar examples?	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9569217562675476, "perplexity": 390.49494758071734}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-13/segments/1521257648003.58/warc/CC-MAIN-20180322205902-20180322225902-00072.warc.gz"}
http://mymathforum.com/complex-analysis/15196-finding-real-number-complex-number.html	My Math Forum Finding real number in complex number Complex Analysis Complex Analysis Math Forum October 18th, 2010, 02:13 PM #1 Member Joined: Apr 2010 Posts: 91 Thanks: 0 Finding real number in complex number Find real numbers x, y such that $(1 - 3i)x + (2 + 5i)y= 2i$ I dont know what to do. October 18th, 2010, 04:38 PM #2 Global Moderator Joined: Nov 2009 From: Northwest Arkansas Posts: 2,766 Thanks: 4 Re: Finding real number in complex number Quote: Originally Posted by TsAmE Find real numbers x, y such that $(1 - 3i)x + (2 + 5i)y= 2i$ I dont know what to do. Distribute... x -3xi + 2y + 5yi = 2i Group real and imaginary parts (x + 2y) + (-3x + 5y)i = 0 + 2i. Notice that I added the "0" on the right side. The real part on the left is x + 2y. We equate that to the real part on the right side = 0 So x + 2y = 0. Similarly, we equate imaginary parts. -3x + 5y = 2 Solve the system of equations! Tags complex, finding, number, real Thread Tools Display Modes Linear Mode Similar Threads Thread Thread Starter Forum Replies Last Post sebaflores Real Analysis 1 October 12th, 2013 11:20 AM stealth4933 Real Analysis 1 October 10th, 2013 11:14 AM sachinrajsharma Algebra 1 March 25th, 2013 09:03 AM pinion Calculus 2 August 12th, 2009 08:27 AM symmetry Algebra 2 February 3rd, 2007 09:31 AM Contact - Home - Forums - Cryptocurrency Forum - Top	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 2, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.40567100048065186, "perplexity": 4374.145010876546}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-30/segments/1500549423486.26/warc/CC-MAIN-20170720201925-20170720221925-00641.warc.gz"}
http://granulares.frlp.utn.edu.ar/en/publication/gmg-020/	# Experimental proof of faster-is-slower in systems of frictional particles flowing through constrictions. Type Publication Physical review. E, Statistical, nonlinear, and soft matter physics	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8978926539421082, "perplexity": 15315.60514176683}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-40/segments/1664030337731.82/warc/CC-MAIN-20221006061224-20221006091224-00158.warc.gz"}
https://cs.nyu.edu/crg/newAbstracts/vinod_abstract_9_17_08.html	Vinod Vaikuntanathan IBM Watson TITLE: Trapdoors for Hard Lattices and New Cryptographic Constructions ABSTRACT: We show how to construct a variety of trapdoor'' cryptographic tools assuming the worst-case hardness of standard lattice problems (such as approximating the shortest nonzero vector to within small factors). The applications include trapdoor functions with \emph{preimage sampling}, simple and efficient hash-and-sign'' digital signature schemes, universally composable oblivious transfer, and identity-based encryption. A core technical component of our constructions is an efficient algorithm that, given a basis of an arbitrary lattice, samples lattice points from a Gaussian-like probability distribution whose standard deviation is essentially the length of the longest vector in the basis. In particular, the crucial security property is that the output distribution of the algorithm is oblivious to the particular geometry of the given basis.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9019358158111572, "perplexity": 3408.3095393863114}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-30/segments/1531676590199.42/warc/CC-MAIN-20180718135047-20180718155047-00208.warc.gz"}
https://electronics.stackexchange.com/questions/214891/is-an-ideal-transformer-an-ideal-current-source	# Is an ideal transformer an ideal current source? I define every circuit element of a primary coil of a transformer that is connected to a voltage source and calculate $I_1$ (current of the primary loop). I then connect it to a secondary coil with a known number ($N$) turns. Regardless of the values of the secondary coil, I always can calculate $I_2$ (current in secondary coil) by using $$I_2=\frac{N_2}{N_1}I_1$$ Does it mean that an ideal transformer is an ideal current source? • An ideal source? Yes. An ideal independent source? No, it's an ideal dependent source; specifically, it's a current-dependent current source in one side. I've written an answer explaining this in detail. – Alejandro Nava Sep 25 '20 at 17:12 Does it mean that an ideal transformer is an ideal current source? An ideal transformer will have infinite magnetization inductance and, because of this, it will take zero primary current when there is zero secondary current. This doesn't make it an ideal current source. Look at the equivalent circuit: - An ideal transformer doesn't have any series elements so basically they become shorts. It doesn't have any parallel losses so Gc becomes open circuit and the only contentious thing left is the primary magnetization inductance shown with a blue square surrounding it. For an ideal transformer this is infinite in value and no current can flow into the primary if there is no load on the secondary. If there is load on the secondary then the primary impedance looking in will have an impedance of: - $$\P_Z = (\dfrac{N_1}{N_2})^2 \times S_Z\$$ You could argue that a CT (current transformer) might be an ideal current source but it isn't. With a high primary current of (say) 100 amps it still has a primary magnetization inductance that will naturally limit the open circuit secondary output voltage despite rumours of thousands of volts being talked about on some websites. • @Andyaka Well, you can't have ideal current source in open circuit as well. – Eugene Sh. Feb 2 '16 at 15:53 • So in this sense the transformer with forced primary current will be equivalent to a current source – Eugene Sh. Feb 2 '16 at 15:55 • @MaryE an ideal transformer connected to an impedance on the secondary will look like that impedance on the primary except it will be multiplied in magnitude by the turns ratio squared. For a 1:1 transformer connected to a 10 ohm resistor, the primary will look like a 10 ohm resistor. Nothing to do with it being an ideal current source. – Andy aka Feb 2 '16 at 16:02 • Ok I get it now. The current on the primary circuit depends on the impedance of the secondary circuit, therefore the current in the secondary circuit depends on its impedance (hiding in I1 in equation). So it is not an ideal current source, except when we have an ideal current source on primary, then an ideal transformer acts like an ideal current source as Eugene said. – Jack Feb 2 '16 at 16:05 • @MaryE Yes, If you have an ideal current source feeding the ideal transformer primary then it looks like an ideal current source on the secondary. – Andy aka Feb 2 '16 at 16:13 An ideal current source will produce the specified current independent of load. See this Wikipedia page for more details A transformer secondary has an effective impedance (due to the turns ratio and the impedance on the primary) so the current will change dependent on the load and the primary circuit. Therefore, the secondary can't be modelled as an ideal current source unless the primary is connected to an ideal current source. • The question is about an ideal transformer. – Andy aka Feb 2 '16 at 15:39 • Hopefully clarified my answer now. – rolinger Feb 2 '16 at 15:46 • Secondary can be modelled as an ideal current source, if the primary is connected to ideal current source. – Eugene Sh. Feb 2 '16 at 15:49 I think there's a confusion in some comments and maybe answers. It's important to distinguish between an ideal or non-ideal source, and, an independent or dependent source. An ideal source has no series impedance or shunt admittance, while a non-ideal source has. An independent current source provides the current given by its analytical expression regardless of the voltage across it, while a current-dependent current source provides a current proportional to another current. Does it mean that an ideal transformer is an ideal current source? An ideal transformer isn't an ideal independent current source. From one point of view, this doesn't make sense because a source has two terminals, while a single-phase two-winding transformer has four. An ideal transformer is an ideal voltage-dependent voltage source in one side, and, an ideal current-dependent current source in the other side. This is shown in the following image, taken from Introduction to Electric Circuits (9th edition) by Richard Dorf and James Svoboda, where it's shown an ideal transformer with positive spatial orientation. The derivation of the equivalent circuit on the right is straightforward. You start with the equations $$\N_1/N_2 = v_1(t)/v_2(t)\$$ and $$\N_1/N_2 = -i_2(t)/i_1(t)\$$ (which are valid for the chosen reference polarity of $$\v_1(t)\$$ and $$\v_2(t)\$$, the chosen reference direction for $$\i_1(t)\$$ and $$\i_2(t)\$$, and the fact that the transformer has a positive spatial orientation.) Solve for $$\v_2(t)\$$ and $$\i_1(t)\$$ to get: $$\v_2(t) = \dfrac{N_2}{N_1} v_1(t) \tag 1\$$ $$\i_1(t) = -\dfrac{N_2}{N_1} i_2(t) \tag 2\$$ Notice the first equation has units of volts, while the second of amperes. In other words, to model them as an equivalent circuit, we can assume we can get them by applying KVL and KCL. Furthermore notice in the right-hand side of both equations the voltage $$\v_1(t)\$$ and current $$\i_2(t)\$$ have a coefficient different from 1, which means they can't be modeled as an ideal independent voltage source and an ideal independent current source. But we can model them as ideal dependent sources! Since the coefficient for both is $$\N_2/N_1\$$, we can use dependent sources with a gain equal to that. Taking into account the signs, finally you get the equivalent circuit above. To prove the equivalent circuit is correct, apply KCL at the upper node of the primary side. You get $$\ \text{(currents entering)} = \text{(currents exiting)} \implies i_1(t) + \dfrac{N_2}{N_1} i_2(t) = 0 \implies i_1(t) = -\dfrac{N_2}{N_1} i_2(t) \tag{}\$$ which is the same as equation (2). Apply KVL at the loop of the secondary side in clockwise direction to get $$\ \text{(voltage rises)} = \text{(voltage drops)} \implies \dfrac{N_2}{N_1} v_1(t) = v_2(t) \tag{}\$$ which is the same as equation (1). Thus the equivalent circuit is valid. • Have you downvoted my answer. If so, maybe you could provide an explanation. All your answer appears to be doing is re-affirming that $V_{OUT}$ is $V_{IN}$ multiplied by the turns ratio. What has this got to do with the question? – Andy aka Sep 25 '20 at 17:29 • Hi Andy. No, I didn't downvote your answer (nor any other.) Look here. The downvotes were already there. – Alejandro Nava Sep 25 '20 at 20:03 • Yes, my answer affirms input voltage is proportional to output voltage, where the proportionality constant is the turns ratio (or the reciprocal of it.) But I indeed adress the question. The user said if an ideal tranaformer was an ideal current source. I said it was impossible to substitute the Tx with an ideal independent current source, and suggested an equivalent circuit using dependent sources. – Alejandro Nava Sep 25 '20 at 21:03	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 16, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7672635912895203, "perplexity": 580.9502765322928}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-31/segments/1627046154304.34/warc/CC-MAIN-20210802043814-20210802073814-00164.warc.gz"}
https://zbmath.org/?q=an:1033.53004	× # zbMATH — the first resource for mathematics Minkowski geometric algebra of quaternion sets. (English) Zbl 1033.53004 As a natural extension of interval-arithmetic methods for monitoring propagation of errors or uncertainties in real-number computations, R. T. Farouki, H. P. Moon and B. Ravani [Geom. Dedicata 85, 283–315 (2001; Zbl 0987.51012)] introduced a geometric algebra of point sets in the complex plane which is based on the fundamental operations of forming Minkowski sums and Minkowski products, that is, for two sets one forms the sets of all sums or products, respectively, of elements, one from each operand. In the paper under review the authors extend the definitions and methods of Farouki et al. from the complex numbers to the quaternions. Most rules remain valid but extra care has to be taken due to the non-commutativity of quaternion multiplication. Some geometric interpretations of Minkowski products are provided and simple examples relating to bodies of revolution with radial symmetry axes are given. In the last section of the paper the authors propose a generalisation which can be used to construct a large class of surfaces and solids, including all canal surfaces and ruled surfaces. ##### MSC: 53A07 Higher-dimensional and -codimensional surfaces in Euclidean and related $$n$$-spaces 20G20 Linear algebraic groups over the reals, the complexes, the quaternions 51B20 Minkowski geometries in nonlinear incidence geometry	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.731567919254303, "perplexity": 777.4440767574454}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178376006.87/warc/CC-MAIN-20210307013626-20210307043626-00194.warc.gz"}
https://puzzling.stackexchange.com/questions/35910/variation-of-1000-bottles-of-wine-puzzle/35977#35977	# Variation of 1000 bottles of wine puzzle So I came up with a variation of the famous problem https://www.reddit.com/r/math/comments/3o0mfi/a_king_1000_bottles_of_wine_10_prisoners_and_a/ There are n bottles, with each bottle independently having a probability p_poison that it is poisoned, and for every instance of a test subject drinking from a poisoned bottle there is a probability kill_chance that the poison takes effect after 24 hours. The winning algorithm is the one that uses the least amount of test subjects (on average) to have a 75% or better chance to find at least one poisoned bottle (if any) in the 24 hour window. Unless otherwise stated, all the rules and constraints from the original problem (as stated in the reddit link above) apply. (Edited for clarity) • The original problem is also here. – f'' Jun 13 '16 at 14:09 • For clarification, do you just need to find one poisoned bottle even if there are more than one, or do you need to find all of them? – f'' Jun 13 '16 at 14:09 • (I've edited the tags, enigmatic-puzzle is for puzzle where you don't know the goal of the puzzle. Feel free to edit back if I have made a mistake) Jun 13 '16 at 14:14 • If we're averaging, we need a probability distribution on the number of poisoned bottles. Should we assume that all configurations that don't have too many poisoned bottles are equally probable? Jun 13 '16 at 14:21 • What exactly does "let's assume a standard bell curve" mean here? (I dont actually see anything here that can be distributed that way -- it's a continuously varying thing that can go out to plus or minus infinity.) Perhaps what you actually want is something like this: there's a certain probability p (which might be, say, 5%) and then each bottle is independently poisoned or not with probability p of being poisoned. Jun 13 '16 at 23:00 As you are only asking to find at least one bottle of poisoned wine, and given that there are no time constraints, it can be shown that the minimum number of test subjects needed is one test subject. I make the reasonable assumptions that: • only a drop of wine is needed for testing. • the poison is sufficiently fast-acting that the fatal effects will be seen after only a short wait, rather than manifesting over a number of weeks in cases such as polonium poisoning. The testing sequence would follow: 1.Feed your test subject a sample of wine. 2.Wait a short time. - If test subject dies, you have found your bottle of poisoned wine. - If test subject lives, wine is ok, and repeat from Step 1. 3.If test subject is showing signs of intoxication, let them rest quietly in the corner/their cell for a period before repeating from Step 1. To identify one poisoned bottle, you will need 10 bits of information. Let each subject be one of those bits. Number the bottles $0,\dots,999$ and get 10 subjects, and number them with powers of $2$: $1,2,4,\dots,512$. Prepare for each subject $b$ a mixture from each bottle $a$ where $a\; \&\; b=b$, where $\&$ is bitwise "and". The sum of the numbers of the subjects who keel over from the poison identifies the bottle. Given that we are attempting to find a single poisoned bottle if one exists (and no information about which bottles are not poisoned) I can only assume that ...we wish to poison somebody! In this case we may achieve our aim with $0$ test subjects Because since even a trace of the poison will kill, we may pour all but $\frac1n$ out from one bottle and add $\frac1n$ from each of the other $n-1$ bottles into it, to give us a bottle that is poisoned if any were. • The original problem states that you need to find out which bottle was poisoned, not just that a poisoned bottle exists. Jun 13 '16 at 22:52 • Yep, but your problem stated (until the edit) that you wanted to find a single poisoned bottle if one exists; this answers that problem. Also, I feel like the problem in it's current state needs a better description. Is it that n delegates have arrived, each with a bottle of wine, and on average some number are poisoned drawn from a normal distribution (with what variance?) and that our tests also have a false negative chance? Which data do we know? Jun 13 '16 at 23:03 Since you don't have the time constraint it can be done with 11 rats/prisoners, using a bisection algorithm. 1. Mix a drop from each bottle and feed it to rat 1. If it lives, you've got no poison, so have a party. If it dies go on to step 2. 2. Mix a drop from bottles 1-500 and feed it to rat 2. Depending whether it lives or dies, you can select the group where the poison is (note, you're throwing away information here, because you're just looking for 1 bottle, not all of them). Continue in this way, and you'll be down to 1 bottle by the time you've got through 11 rats. If you know at least one is poisoned, you can skip the first step and do it in 10 rats. • You forgot that the poison doesn't always work, and that the original problem states that you have a time constraint of the same length of time that the poison takes to work. Jun 14 '16 at 6:16	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5848934054374695, "perplexity": 713.9654244083948}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323585199.76/warc/CC-MAIN-20211018062819-20211018092819-00249.warc.gz"}
https://testbook.com/question-answer/the-equation-of-the-line-when-the-portion-of-it-i--5eba8b45f60d5d76ccb8a96e	# The equation of the line, when the portion of it intercepted between the axes is divided by the point (2, 3) in the ratio of 3 : 2 is This question was previously asked in NDA (Held On: 22 April 2018) Maths Previous Year paper View all NDA Papers > 1. Either x + y = 4 or 9x + y = 12 2. Either x + y = 5 or 4x + 9y = 30 3. Either x + y = 4 or x + 9y = 12 4. Either x + y =5 or 9x + 4y = 30 Option 4 : Either x + y =5 or 9x + 4y = 30 Free Electric charges and coulomb's law (Basic) 49600 10 Questions 10 Marks 10 Mins ## Detailed Solution Concept: 1. The intercept form of the line$$\frac{x}{a} + \frac{y}{b} = 1$$ Where a is the x- intercept and b is the y- intercept 1. Section Formula: Section formula is used to determine the coordinate of a point that divides a line into two parts such that ratio of their length is m : n 2. Let P and Q be the given two points (x1, y1) and (x2, y2) respectively and M(x, y) be the point dividing the line- segment PQ internally in the ratio m: n 1. Internal Section Formula: When the line segment is divided internally in the ration m: n, we use this formula. ⇔ $$\left( {x,{\rm{\;}}y} \right) = \left( {\frac{{m{x_2}{\rm{\;}} + {\rm{\;}}n{x_1}}}{{m\; + {\rm{\;}}n}},\frac{{m{y_2}{\rm{\;}} + {\rm{\;}}n{y_1}}}{{m\; + {\rm{\;}}n}}} \right)$$ 2. External Section Formula: When the point M lies on the external part of the line segment. ⇔ $$\left( {x,{\rm{\;}}y} \right) = \left( {\frac{{m{x_2} - {\rm{\;}}n{x_1}}}{{m\; - {\rm{\;}}n}},\frac{{m{y_2} - {\rm{\;}}n{y_1}}}{{m\; - {\rm{\;}}n}}} \right)$$ Calculation: Intercept form of the line is $$\frac{x}{a} + \frac{y}{b} = 1$$ At x axis point is A (a, 0) At y axis point is B (0, b) Case 1: Given point P (2, 3) divides A and B in ratio of m : n = 3 : 2 Applying Internal Section Formula, We know that $$\left( {x,{\rm{\;}}y} \right) = \left( {\frac{{m{x_2}{\rm{\;}} + {\rm{\;}}n{x_1}}}{{m\; + {\rm{\;}}n}},\frac{{m{y_2}{\rm{\;}} + {\rm{\;}}n{y_1}}}{{m\; + {\rm{\;}}n}}} \right)$$ $$\Rightarrow \;\left( {2,\;3} \right) = \;\left( {\frac{{3\left( 0 \right) + \;2\left( a \right)}}{{3 + 2}},\frac{{3\left( b \right) + 2\left( 0 \right)}}{{3 + 2}}} \right)$$ $$\Rightarrow \;\left( {2,\;3} \right) = \;\left( {\frac{{2a}}{5},\frac{{3b}}{5}} \right)$$ Now, $$\frac{{2a}}{5} = 2\;and\;\frac{{3b}}{5} = 3$$ ⇒ a = 5 and b = 5 ∴ Equation of line is $$\frac{x}{5} + \frac{y}{5} = 1$$ ⇒ x + y = 5 Case 2: Given point P (2, 3) divides A and B in ratio of m : n = 2 : 3 $$\Rightarrow \;\left( {2,\;3} \right) = \;\left( {\frac{{2\left( 0 \right) + \;3\left( a \right)}}{{3 + 2}},\frac{{2\left( b \right) + 3\left( 0 \right)}}{{3 + 2}}} \right)$$ $$\Rightarrow \;\left( {2,\;3} \right) = \;\left( {\frac{{3a}}{5},\frac{{2b}}{5}} \right)$$ Now, $$\frac{{3a}}{5} = 2\;and\;\frac{{2b}}{5} = 3$$ ⇒ a = 10/3 and b = 15/2 ∴ Equation of line is $$\frac{x}{\left( {}^{10}\!\!\diagup\!\!{}_{3}\; \right)}+\frac{y}{\left( {}^{15}\!\!\diagup\!\!{}_{2}\; \right)}=1$$ $$\Rightarrow {\rm{\;}}\frac{{3x}}{{10}} + \frac{2}{{15}} = 1$$ ⇒ 9x + 4y = 30 Shortcut Method: • Check through the options: Substitute the point (2, 3) in all options ⇒ Only option 4 satisfied the point (2, 3), so option 4 is correct.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9323874115943909, "perplexity": 701.0639550493922}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-49/segments/1637964363290.59/warc/CC-MAIN-20211206072825-20211206102825-00194.warc.gz"}
https://www.tubesandmore.com/products/integrated-circuits?sort=price_high_to_low	# Integrated Circuits Evaluation Board - EVB2130-P, SSI2130 VCO, Sound Semiconductor, Fully Populated The SSI2130 offers unprecedented performance and features, but its ultra-compact QFN package can present prototyping challenges. The EVB2130 eases evaluation by providing a PCB that allows comprehensive exploration of capabilities. The EVB2130-P is fully populated and ready for the bench. With the exception of the SSI2130, all components are through-hole for easy construction and experimentation. A on-board +5V regulator and 2.5V reference simplify external power connections, and pots are provided for mixer control, PWM, and VCO setup. Switches ease selection of saw ramp direction plus Through-Zero and Pulse Modulation. Features • PCB size: 108 x 82mm • External Power: ±12V • Inputs: Expo Freq 1V/Oct PWM In Aux 1 and 2 In FM In PM In Hard Sync Soft Sync • Outputs: Sine Saw Triangle Pulse Square Mix Out $110.95 Integrated Circuit - Xvive, MN3005, BBD, 4096 Stage The XVive MN3005 is a drop-in replacement for the original Panasonic 4096-stage MN3005 BBD chip used in many delay pedals and effects. Xvive Audio’s first-ever product was the MN3005: a re-creation of the legendary bucket brigade chip used in the Deluxe Memory Man and many other iconic effect pedals and instruments. Now, the Xvive MN3005 is at the heart of delay pedals produced by some of the world’s top effect pedal brands. The MN3005 is the world’s first 4096-stage long-delay BBD—eight times longer than the 512-stage BBD. It is manufactured using a P-channel low-noise silicon gate process. A long-signal delay time of 205 ms can be obtained at a clock frequency 10 kHz, with a sound-to-noise ratio of 75dB. This ratio is an improvement of 20dB, as compared to eight connected 512-stage BBDs!$22.95 Integrated Circuit - DAB2140, Multi-Mode VCF, Sound Semiconductor The Sound Semiconductor DAB2140 is a pre-soldered DIP converter for the SSI2140. This board features the SSI2140 and two decoupling caps for the V+ and V- inputs. The pinout is labelled on the board and matches the SSOP pinout. This adapter features a 20 pin DIP base with a .600 in. width. The pins are standard male headers so 2.54mm female headers are recommended for socketing the board. For the SSOP version, please see P-Q-SSI2140. A refresh of a classic design, the FatKeys™ SSI2140 preserves mojo of the beloved SSM2040 and adds temperature compensation of gm cells and the exponential control port. A "Q VCA" is provided to allow easy resonance control as well as various options for Q compensation. $19.95 Integrated Circuit - Experimental Noize FXCore, DSP, Multi-Effect / Reverb FXCore from Experimental Noize is a DSP designed for creating audio effects in pro-audio devices. FXCore can operate as a standalone device when paired with appropriate CODECs where it generates all necessary clocks or as part of a more complex system where it will lock to the word clock and bit clock provided by another part of the system. FXCore can store up to 16 programs and their associated register preset values in its internal FLASH memory so no external program storage is required.$19.95 Integrated Circuit - DAB2130, VCO, Sound Semiconductor The Sound Semiconductor DAB2130 is a pre-soldered DIP converter for the SSI2130. This board features the SSI2130 and two decoupling caps for the V+ and V- inputs. The pinout is labelled on the board and matches the QFN pinout. This adapter features a 32 pin DIP base with a .600 in. width. The pins are standard male headers so 2.54mm female headers are recommended for socketing the board. For the standard QFN version, please see P-Q-SSI2130. The first new VCO IC in decades, and worth the wait! The FatKeys™ SSI2130 Voltage Controlled Oscillator provides beautiful triangle, sawtooth, pulse, and square waveforms with unprecedented temperature stability; and adds an on-chip mixer, low distortion sine wave generator, through-zero FM/PM capability and more in an ultra-compact PCB footprint. The SSI2130 is a new-generation voltage controlled oscillator subsystem for high-performance electronic musical instruments. $19.95 Integrated Circuit - Spin FV-1, DSP, Multi-Effect / Reverb The Spin Semiconductor FV-1 is a complete reverb solution in a single IC. With integrated stereo ADC and DACs, the FV-1 can be treated like any other analog component in your product's signal path. The FV-1 can access a total of 16 programs, 8 are built into the internal ROM and the designer may elect to connect a serial EEPROM with 8 additional programs. By using an external EEPROM, the designer can distinguish his product from others by creating a custom program set without the need for a microprocessor in the system. With 3 potentiometer inputs, programs may have real time variable parameters such as decay time in a reverb, rate and depth in a chorus or frequency in a filter. These inputs are available as coefficients to your program and may be used independently of each other. The rich instruction set allows users to program effects of all kinds. With instructions like LOG and EXP, users can easily program audio expansion and compression routines.$17.50 Integrated Circuit - Xvive, MN3009, BBD, 256 Stage The XVive MN3009 is a drop-in replacement for the original Panasonic 256-stage MN3009 BBD chip used in many chorus, vibrato, and flanger pedals and effects. The MN3009 is a 256-stage BBD that boasts a wide dynamic range and low distortion. Its signal delay of up to 12.8 milliseconds makes it a perfect choice for vibrato and/or chorus effects in electronic musical instruments. $13.95 Integrated Circuit - Xvive, MN3007, BBD, 1024 Stage The XVive MN3007 is a drop-in replacement for the original Panasonic 1024-stage MN3007 BBD chip used in many chorus, vibrato, and flanger pedals and effects. The MN3007 is a 1024-stage, low-noise, long-delay BBD that provides a signal delay of up to 51.2 milliseconds. Due to its long delay times, the MN3007 is especially suitable for reverb effects in electronic musical instruments and PA equipment.$13.95 Integrated Circuit - Marshall, TDA7293 amplifier 120V - 100W DMOS audio amplifier with mute/standby. The TDA7293 is a monolithic integrated circuit in Multiwatt15 package, intended for use as audio class AB amplifier in Hi-Fi field applications, such as home stereo, self powered loudspeakers and Topclass TV. Thanks to the wide voltage range and to the high output current capability it is able to supply the highest power into both 4-Ω and 8-Ω loads. $11.95 Integrated Circuit - AS3372E, Synth Voice, Alfa, 24 Pin DIP The AS3372E is Alfa’s take on the CEM3372 µP Controllable Signal Processor in a DIP-24 package. The AS3372E features an additional two VCA’s so an adapter board is required when using as a replacement for the CEM version. The CEM version was used in multiple classic synths, including the Oberheim Matrix 12, Oberheim Xpander, Sequential Prophet T8, Sequential Prophet 600, Akai AX80, Rhodes Chroma Polaris, and more.$10.95 Op-Amp - LM358H, Dual, 8-Pin TO-99 LM358H dual op amp in an 8-pin TO-99 package. The LM358H series consists of two independent, high gain, internally frequency compensated operational amplifiers which were designed specifically to operate from a single power supply over a wide range of voltages. Operation from split power supplies is also possible and the low power supply current drain is independent of the magnitude of the power supply voltage. Application areas include transducer amplifiers, dc gain blocks and all the conventional op-amp circuits which now can be more easily implemented in single power supply systems. $10.95 Op-Amp - LM308, Motorola, Single, 8-Pin CDIP NOS LM308 from Motorola in an 8-pin ceramic DIP package. The LM308 operational amplifiers provide high input impedance, low input offsets and temperature drifts, and low noise. These characteristics are made possible by use of a special Super Beta processing technology. This series of amplifiers is particularly useful for applications where high-accuracy and low-drift performance are essential. In addition high-speed performance may be improved by employing feed-forward compensation techniques to maximize slew rate without compromising other performance criteria.$9.95 Integrated Circuit - SSI2130, VCO, Sound Semiconductor The FatKeys™ SSI2130 Voltage Controlled Oscillator provides beautiful triangle, sawtooth, pulse, and square waveforms with unprecedented temperature stability; and adds an on-chip mixer, low distortion sine wave generator, through-zero FM/PM capability and more in an ultra-compact PCB footprint. $8.95 OTA - AS3280, Dual, Linearizing Diodes, Alfa, 16-Pin DIP The AS3280 is Alfa’s version of the CA3280 IC. The AS3280 consists of two variable operational amplifiers that are designed to substantially reduce the initial input offset voltage and the offset voltage variation with respect to changes in programming current. This design results in reduced "AGC thump," an objectionable characteristic of many AGC systems. Careful design of critical places of the circuit reduces the amplifier dependence upon thermal and processing variables. The AS3280 has all the generic characteristics of an operational voltage amplifier except that the forward transfer characteristics is best described by transconductance rather than voltage gain, and the output is current, not voltage. The magnitude of the output current is equal to the product of transconductance and the input voltage.$7.95 Integrated Circuit - AS3340A, VCO, Alfa, 16-Pin Dip The AS3340A is Alfa’s version of the CEM3340 IC. The AS3340A is a completely self-contained, precision voltage controlled oscillator, featuring both exponential and linear control scales and up to four buffered output waveforms: triangle, sawtooth, square, and pulse with voltage controllable pulse width. Full temperature compensation makes these VCOs extremely stable, and eliminates the need for a temperature compensation resistor. The highly accurate exponential and linear control inputs are virtual ground summing nodes, allowing multiple control voltages to be mixed within the device itself. Also included is provision for hard and soft synchronization of the frequency, and an output for easy adjustment of high frequency tracking. Special care in the design ensures oscillation start-up under any power-on sequence and supply conditions. An on-chip 7.4 volt Zener diode allows the device to operate off ±15 volt supplies, as well as +12, -5 volt supplies. $7.95 Op-Amp - AS301AH, Alfa, Single, TO5-8 case The AS301AH is Alfa’s version of the LM301A in an 8 pin TO5 package. The AS301A is a general purpose operational amplifier. This amplifier offers many features which make its application nearly foolproof: overload protection on the input and output, no latch-up when the common mode range is exceeded, and freedom from oscillations and compensation with a single 30 pF capacitor. It has advantages over internally compensated amplifiers in that the frequency compensation can be tailored to the particular application. For example, in low frequency circuits it can be overcompensated for increased stability margin. Or the compensation can be optimized to give more than a factor of ten improvements in high frequency performance for most applications. In addition, the device provides better accuracy and lower noise in high impedance circuitry.$7.95 OTA - AS3280D, Dual, Linearizing Diodes, Alfa, SOIC-16 The AS3280 is Alfa’s version of the CA3280 IC in an SOIC package. The AS3280D consists of two variable operational amplifiers that are designed to substantially reduce the initial input offset voltage and the offset voltage variation with respect to changes in programming current. This design results in reduced "AGC thump," an objectionable characteristic of many AGC systems. Careful design of critical places of the circuit reduces the amplifier dependence upon thermal and processing variables. The AS3280D has all the generic characteristics of an operational voltage amplifier except that the forward transfer characteristics is best described by transconductance rather than voltage gain, and the output is current, not voltage. The magnitude of the output current is equal to the product of transconductance and the input voltage. $7.95 Integrated Circuit - AS3109D, VCF, Alfa, SOIC-16 The AS3109 is Alfa’s version of the Roland IR3109 VCF in an SOIC package. The AS3109 is a high performance voltage controlled four-pole filter. The four independent sections may be interconnected to provide a wide variety of filter responses, such as low pass, high pass, band pass and all pass. A single input exponentially controls the frequency over a range greater than 15 octaves with little control voltage feedthrough. AS3109 features high input impedance buffers. Features • Voltage controllable range – 15 octaves • Accurate exponential frequency scale • High input impedance buffers • Wide transconductance range • Low input offset voltage • Low control voltage feedthrough - 45 dB typical Applications • For electronic music$7.95 Integrated Circuit - AS3360, Dual VCA, Alfa, 14-Pin Dip The AS3360 is Alfa’s version of the CEM3360 IC. The AS3360 is a dual general purpose voltage controlled transconductor intended for such applications as voltage controlled amplifiers, filters, and waveform generators. Each transconductor independently provides both linear and exponential control scaling over greater than a 100 dB range. Complete with virtual ground summing inputs, wide voltage compliance current outputs, and control inputs referenced to ground, the AS3360 requires exceptionally few external components and is extremely easy to use. Because of its inherent ultra-low control feedthrough, no trimming is required. $7.95 Integrated Circuit - SSI2131, VCO, Sound Semiconductor The FatKeys™ SSI2131 Voltage Controlled Oscillator provides the core VCO function with buffered triangle, sawtooth, and variable-width pulse waveform outputs over a ten-octave range. The device offers unparalleled temperature stability, exponentiality, waveform integrity, and ease of use while requiring an absolute minimum of external components. The SSI2131 is a new-generation voltage controlled oscillator for high-performance electronic musical instruments and other systems requiring accurate audio-band waveform generation. The device offers unprecedented levels of temperature stability, exponentiality, waveform integrity, and ease of use.$7.50 Integrated Circuit - SSI2164, Quad VCA, Sound Semiconductor The FatKeys™ SSI2164 is perhaps the most flexible VCA available, with four independent channels for lowest cost-per-VCA. The user-selectable mode control allows Class A, AB, or intermediate biasing, and current inputs and outputs provide great design freedom. Ideal for voltage-controlled filters. The SSI2164 is a versatile VCA building block for high-performance audio applications. Four independent channels provide voltage control of current-mode inputs and outputs for a gain range from +20dB to –100dB, with control provided by a ground-referenced –33mV/dB constant. The SSI2164 will directly retrofit existing SSM/V2164 positions while offering improvements that include significantly lower overall distortion, on-chip protection against asymmetrical power failure, and a substantial increase of input current handling. The device offers considerable flexibility for a wide range of design goals and applications. $6.95 Integrated Circuit - SSI2144, Ladder VCF, Sound Semiconductor The second of two legendary SSM filter updates, the FatKeys™ SSI2144 is a dedicated four-pole low-pass ladder filter with on-chip resonance control. Original designer Dave Rossum did a number of performance updates such as lower noise, improved control feedthrough, and logical pin grouping but otherwise left this sweet-sounding VCF alone. The SSI2144 reprises the SSM2044 of legacy chipmaker Solid State Micro Technology, which many believe to be the best-sounding analog synthesis filter IC ever produced. Based on Dave Rossum’s patented classic improved ladder topology, the SSI2144 allows rich tonal characteristics that showcase the very best attributes of subtractive synthesis. The SSI2144 uses the same internal circuit as the SSM2044 but incorporates improvements by the original designer and takes advantage of modern process technology.$6.65 OTA - AS3080E, Linearizing Diodes, Alfa, 8-Pin DIP The AS3080E is Alfa’s version of the CA3080 IC. The AS3080E is a gain block which is the operational-transconductance-amplifier (OTA). The AS3080E has differential input and a single-ended, push-pull, class A output. Amplifier bias input may be used either for gating or for linear gain control. High output impedance and transconductance (gM) is directly proportional to the amplifier bias current (IABC). Linearizing diodes are provided at the inputs to reduce distortion and allow higher input levels. The result is a 10-dB signal-to-noise improvement referenced to 0.5 percent THD. The AS3080E is notable for it’s high slew rate (50V/µs), which makes it especially useful for multiplexer and fast unity-gain voltage followers. $6.50 Integrated Circuit - SSI2140, Multi-Mode VCF, Sound Semiconductor The SSI2140 is a new-generation voltage controlled filter that provides four highly-configurable variable transconductance cells for a wide variety of pole and mode combinations, and adds significant new features.$6.50	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.2549690902233124, "perplexity": 11683.186889668172}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-49/segments/1669446711417.46/warc/CC-MAIN-20221209144722-20221209174722-00294.warc.gz"}
https://meangreenmath.com/2016/04/25/sohcahtoa/	# SOHCAHTOA Years ago, when I first taught Precalculus at the college level, I was starting a section on trigonometry by reminding my students of the acronym SOHCAHTOA for keeping the trig functions straight: $\sin \theta = \displaystyle \frac{\hbox{Opposite}}{\hbox{Hypotenuse}}$, $\cos \theta = \displaystyle \frac{\hbox{Adjacent}}{\hbox{Hypotenuse}}$, $\tan \theta = \displaystyle \frac{\hbox{Opposite}}{\hbox{Adjacent}}$. At this point, one of my students volunteered that a previous math teacher had taught her an acrostic to keep these straight: Some Old Hippie Caught Another Hippie Tripping On Acid. Needless to say, I’ve been passing this pearl of wisdom on to my students ever since. ## 2 thoughts on “SOHCAHTOA” 1. Small problem: I get “Formula does not parse” three times. This site uses Akismet to reduce spam. Learn how your comment data is processed.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 3, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.670644223690033, "perplexity": 5993.770074318259}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-49/segments/1669446711108.34/warc/CC-MAIN-20221206124909-20221206154909-00670.warc.gz"}
https://online.ucpress.edu/gp/article-abstract/1/1/16757/111814/The-Euro-as-a-Polity-Karl-Polanyi-in-Frankfurt?searchresult=1	As factors of production, labor, money, and land play a role in economics that is rarely understood. The difficulty of deriving the contribution of the individual factor of production to the value of jointly produced final commodities (the famous “problem of imputation”) occupied generations of Austrian economists (Hayek 1984) and inspired Ludwig Mises to produce his 1920 article “Economic Calculation in the Socialist Commonwealth” (Mises 1935). Any attempt at rational socialist planning is utopian, Mises argued, because only price-making markets for the factors of production provide the information for economically rational decision-making. If the birthplace of neoliberalism was, as Slobodian (2018, p. 30) put it, Ludwig Mises’s office in the Vienna Chamber of Commerce, this article was its moment of birth. Karl Polanyi was one of the first to respond, doing so in the same...	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8179256916046143, "perplexity": 6507.346200252888}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-49/segments/1637964358953.29/warc/CC-MAIN-20211130050047-20211130080047-00133.warc.gz"}
https://www.jiskha.com/members/profile/posts.cgi?name=DAVE	# Posts by DAVE Total # Posts: 870 Vectors the point (3,-4,5), (1,0,5), and (3,1,-2) are three out of four vertices of a parallelogram ABCD. Explain why there are three possibilities for the location of the fourth vortex, and find the point? pre-calculus I have absolutely no idea even where to start. Please help! The carnival has come to town with a ferris wheel that has a radius of 30 feet. People get on when passenger compartments are at the lowest, 2 feet off the ground. The wheel makes a full revolution in 20 seconds. ... Algebra Thank you so much Steve! Algebra How do you solve sin x * cos x = 1/4 I don't know where to start. Algebra Given that $x^n - \frac1{x^n}$ is expressible as a polynomial in $x - \frac1x$ with real coefficients only if $n$ is an odd positive integer, find $P(z)$ so that $P\left(x-\frac1x\right) = x^5 - \frac1{x^5}.$ math a rectangular plate 120 ft long and 80 ft wide is submerged vertically with the longer edge in the surface of the water find the force on one side of the plate mechanics a rectangular plate 120 ft long and 80 ft wide is submerged vertically with the longer edge in the surface of the water find the force on one side of the plate Mechanics The force Fa=(5i+6j+1k) is applied on a material point while it is shifted by 50m in Oxy plane along a direction 20o CCW versus Ox axis. Find the work done by force on the particle during this shift. The answer should be 337.5J What I did: I found the magnitude of the force: 5... Precalculus -- Systems of Equations So my final answer would be 8/sqrt(5). Thanks so much! Precalculus -- Systems of Equations I do not understand this problem. This is part of the question, but I think if I get this part, I'll get the rest. Determine the value(s) of r for which the system: (x^2)+(y^2)=(r^2) x-2y=8 has one real solution. I can't get anywhere! We should solve algebraically... Math Are you given purple marbles, too? chemistry A 40.0-mL sample of 0.100 M HNO2 is titrated with 0.200 M KOH. Calculate the volume required to reach the equivalence point (in mL) History Not c or d well gg History Well then D History "When the war ended in 1945, two-thirds of all American men between the ages of 18 and 34 were in uniform. Experts feared that without wartime production, many returning soldiers might have trouble finding jobs. Unemployment would rise, and the economy would tumble."... History Wiat it's not b it's C History It's not d or c or a so it's B History B i think but how would that help in the workplace it's just voting History Which of the following helped women in the workplace? A the Civil Rights Act of 1964 B the Voting Rights Act of 1965 C the end of segregation D Hernandez v. Texas I think it's D or b Chemistry Nitrogen monoxide reacts with chlorine gas according to the reaction: 2NO (g) + Cl2 (g) â‡” 2NOCl (g) Kp = 0.27 at 700 K A reaction mixture initially contains equal partial pressures of NO and Cl2 . At equilibrium, the partial pressure of NOCl is 115 torr. What... math Amy leaves home at the same time every morning and gets to school exactly at 8 AM. If she traveled at 70 meters per minute she would arrive 10 minutes early. If she traveled at 60 meters per minute she would arrive 8 minutes early. What time does Amy leave home each morning? Social studies B and A Social studies Which of the following was the main contributor to finally bringing the United States out of the Great Depression? A the National Recovery Administration B the Good Neighbor Policy C wartime spending D the election of Roosevelt D or B ----------------------------------- Which ... chemistry For the reaction 2Na(s)+Cl2(g)?2NaCl(s)2Na(s)+Cl2(g)?2NaCl(s), how many grams of NaCl could be produced from 20 L of Cl2Cl2 (at STP)? Calculus The region enclosed by the graph e^(x/2), y=1, and x=ln(3) is revolved around the x-axis. Find the volume of the solid generated. I don't understand if we have to use the washer method or the disk method for this one because when I drew it out on a graph it looked very ... Social Studies Number 2 only has 1 answer Social Studies 1. Which of the following apply to fascism? Select all that apply. A rooted in militarism B extreme nationalism C respect for minorities D blind loyalty to the state I think its A,B, and c ----------------------------------- 2. Which of the following best describes attitudes ... Social Studies Which action is often viewed as the most serious attempt to undermine the independence of the judiciary? A President Franklin D. Roosevelt’s plan to reorganize the Supreme Court B appointment of Supreme Court justices to unlimited terms of office C periodic increases in ... Social studies Lol thx man Social studies Which of the following factors was most responsible for an unequal distribution of wealth? A There was an increase in business profits. B Wages were not keeping pace with profits of business owners. C Wages were not keeping pace with profits of business owners. D There was ... physics an object starts from rest and accelerates uniformly to a speed of 100 m s^-1 after 5s. calculate the acceleration of the object. math Fido weighs 26 pounds more than Fifi. Fifi weighs 12 pounds less than Rover. If the sum of their weights is 71, how much does Fifi weigh? Math A basket ball team scored a total of 160 points. they made 74 baskets. how many 2 point and how many 3 point shots? math The perimeter of the isosceles triangle is 28 cm.and side a is equal to (x+2y) while side b is equal to (6y-2x+1) and side c is equal to 4y all in cm.find x and y and hence state the lengths of the side of the triangle maths whats yearly intrest on 52 grand in a isa at intrest rate 1.5 yearly Maths If the volume of a cylindrical block is equal to 800cm^3 prove that the total surface area is equal to 2(pi)x^2 + (1600)/x, where x cm is the radius of the base. hence obtain the value x which makes the surface area a minimum. Math 6550=3250ft^2 so 1625/3250 0.5\$/ft^2 math Amy & Ashley bike along the same trail. Amy bikes the entire trail at 20mph & Ashley bikes at 15mph. Amy finishes 8 minutes before Ashley. How many miles long is the trail? Chemistry Suppose you titrated a sample of sulfuric acid (diprotic acid) with a 0.250 M solution of NaOH. Given the data in the table below, what is the concentration of the sulfuric acid solution? Math f(x) = cos(x) + 3x Find f^-1 (1) and (f^-1)' (1) f^-1 (1) = 0 (f^-1)' (1) = 1/3 These are the answers given, but I also don't understand how my teacher got these. Math Actually I do have one question, how do we know that x is 1 already ??? Math Thank You so much! Math f(x) = x^5 + 2x^3 + x - 1 Find f^-1 (3) and (f^-1)' (3) f^-1 (3) = 1 (f^-1)' (3) = 1/12 Those are the answers, but I have no clue how my teacher got them. Math lim 200 (30-t)^2 h->0 t=10 The answer should be -8000, but I keep getting -80,000 because I have to do it the long way. math a truck weighting 20000 pounds going 5 mph what is the force of the truck when it hits a person and comes to a complete stop? Math There is a graph of a function that looks like y = x^4 , but it has a vertical asymptote at x = -2 and x = 4. The question then asks us to arrange the following numbers in decreasing order: g'(1), g'(-2), g'(0), g'(2), g'(4) I figured out all of the slopes... Math Is the step function differentiable in its domain? I answered it and said that the step function is not differentiable in its domain because it is not continuous. For the a function to be differentiable it would need to have a value and a limit. However, the step function has ... Mats Exercise 1.7 g (x)= 2\3 (2/3x) (x-2) (x+1) Math Find the 999th derivative of cos x. I got sin x. Math lim (cos(π/4 + h) - cos (π/4)) / h h->0 Math lim (cos(π/4 + h) - cos (π/4)) h->0 _________________________ h Somehow I ended up with cos(1). Math Use the quotient rule to find the derivative of cot x. I tried to solve this, but somehow I got (sec^2x)/(tanx)^2. physics Identify the force that propels a rocket. 1)The rocket is propelled by the reaction force of the exhaust gasses bouncing off the air molecules outside the rocket. 2)The rocket is propelled because the action force of the rocket on the exhaust gases is greater than the reaction... physics Identify the force that propels a rocket. 1)The rocket is propelled by the reaction force of the exhaust gasses bouncing off the air molecules outside the rocket. 2)The rocket is propelled because the action force of the rocket on the exhaust gases is greater than the ... math find the lcm for 6, 18 History What kind of scenes did artists who gained fame tend to paint in the late eighteenth century. Give an example. US History What kind of scenes did artists who gained fame tend to paint in the late eighteenth century. Give an example. Math for Reiny your derivative is correct. now just plug in x = π/2 to get the slope remember that tan(π/2) is undefined, BUT cot (π/2) = cos(π/2) / sin(π/2) = 0/1 = 0 so slope = -csc^2 (π/2) = 2 I calculated and got -1 as the slope. Can you please explain how ... Math Find the inverse of: y = ((-1) / (x+5)) - 1 Math for Reiny your derivative is correct. now just plug in x = π/2 to get the slope remember that tan(π/2) is undefined, BUT cot (π/2) = cos(π/2) / sin(π/2) = 0/1 = 0 so slope = -csc^2 (π/2) = 2 I calculated and got -1 as the slope. Can you please explain how ... Math I calculated and got -1 as the slope. Can you please explain how you got 2 for the slope? Math Find an equation for the tangent line to the curve at (π/2 , 2). y = 4 + cot(x) - 2csc(x) I am confused how to take the derivative of this problem. When I tried to solve it I ended up with -csc^2 (x) + (2csc(x) cot(x)). From there I can't seem to simplify it. Also, ... Physics Why does the force of gravity change the speed of a satellite in an elliptical orbit? 1)The force of gravity is always tangent to the satellite motion. 2)Gravity speeds up the satellite as it moves away and slows it on its return. 3)The force of gravity is always perpendicular... Physics Why does the force of gravity change the speed of a satellite in an elliptical orbit? 1) The force of gravity is always tangent to the satellite motion. 2)Gravity speeds up the satellite as it moves away and slows it on its return. 3)The force of gravity is always ... Physics How can gravity be simulated in an orbiting space station? 1)aped like a bicycle wheel 2)Spin two pods connected by a cable 3)Rotate a cylinder to create centrifugal force as viewed by a person on the inside of the curved outer wall 4)All of the above Physics Which of the following is an element? H2O Hydrogen Carbon dioxide A supernova Physics Which two factors mainly affect ocean tides on Earth? Check two answers. Earth's revolution about both the Moon and the Sun the Moon the Sun the pull of distant planets physics physics The concept of pressure involves both force and volume. force and area. area and volume Physics Why does the force of gravity change the speed of a satellite in an elliptical orbit? 1)The force of gravity is always tangent to the satellite motion. 2)Gravity speeds up the satellite as it moves away and slows it on its return. 3)The force of gravity is always perpendicular... Physics A dike in Holland springs a leak through a hole of area 0.80 cm2 at a depth of 1.2 m below the water surface. How much force must a boy apply to the hole with his thumb to stop the leak? Physics A dike in Holland springs a leak through a hole of area 0.80 cm2 at a depth of 1.2 m below the water surface. How much force must a boy apply to the hole with his thumb to stop the leak? Physics A dike in Holland springs a leak through a hole of area 0.80 cm2 at a depth of 1.2 m below the water surface. How much force must a boy apply to the hole with his thumb to stop the leak? Math Find 2 tangent line equations to the curve y=x^3+x at the points where the slope of the curve is 4. What is the smallest possible slope of the curve? At what x-value(s)does the curve have this slope? So far I have figured out the derivative of this function is y'= 3x^2+1. ... Math Pre- Algebra 2 (75+7.50) or (75+7.50) (2) The total should be 165 dollars. Math lim as x approaches negative infinity (3x^5 + 6x + - 3) / (8x^4 + 10) a. Does Not Exist b. 0 c. -3/8 d. 3/8 I solved this and got negative infinity as the answer, but none of the answers are listed above. I finally chose Choice C, but my teacher said the correct answer is A? Math lim as x approaches negative infinity (3x^5 + 6x + - 3) / (8x^4 + 10) a. Does Not Exist b. 0 c. -3/8 d. 3/8 I solved this and got negative infinity as the answer, but none of the answers are listed above. I finally chose Choice C, but my teacher said the correct answer is A? Calculus Construct a function f : R 2 ¡æ R such that its saddle points are given by {(n, 2m+1−n)\|n ¡ô Z, m ¡ô Z}, where Z is the set of integers. Math The limit as x approaches negative infinity is (3x^5 + x + 2) / (8x^4 - 5) a. DNE b. 0 c. -3/8 d. 3/8 I think the answer is Choice C, but I was stuck between this answer and Choice D. History They systematic raiding of the Athapascans shows that organized warfare is most clearly identified with: a. there is no record of either society initiating organized warfare b. both farming and hunting societies c. neither hunting nor farming societies d. farming societies ... History The map of northeastern region of North America shows the tribes of the Iroquois Confederacy: a. in a staked formation south of the st. lawrence river b. arranged like fingers south of lake ontario c. formed in the shape of a necklace north of the ohio river History I chose choice A. History Teotihuacan like other early urban civilizations was a. self sustaining and unconcerned with long distance trade as a result of its abundant food supply and specialization of labor b. controlled as an elaborate state sponsored trading system that stretched from present day ... History They systematic raiding of the Athapascans shows that organized warfare is most clearly identified with: a. there is no record of either society initiating organized warfare b. both farming and hunting societies c. neither hunting nor farming societies d. farming societies ... Chemistry 1.0 ml Math 380/95 is exactly 4 hours. Maths I have a wheel 40 cm diameter that has 200 N m of torque, assuming there is no slippage what would the force of the wheel on the road? How do I work it out please? Civics To become a law, typically a bill must be approved by: a. The House of Representatives, the Senate, and the President b. The House of Representatives c. The Senate d. The Supreme Court I chose Letter A, but someone how my teacher said it was incorrect. I was completely shocked... Civics To become a law, typically a bill must be approved by: a. The House of Representatives, the Senate, and the President b. The House of Representatives c. The Senate d. The Supreme Court I chose Letter A, but someone how my teacher said it was incorrect. I was completely shocked... Civics I think C is the correct answer. Civics What limits the amount of legal immigrants to our country? a. Tariffs b. Census c. Quotas d. Passports I couldn't find this question on any sources online. My teacher originally gave us this question on the review packet with no answer right answer to it. So, I just ... Civics Thank you so much for your help Writeacher!!! Civics I think it was 5 years at least. Thank you so much for your help Ms. Sue!!! Civics Hi Ms. Sue! I couldn't find anything on the declaration of intention on the website provided. I thought that Letter B wouldn't part of the process, but you need to have a basic understanding of the gov't and english to pass the test. And to do this you need to take... Civics I chose Letter A, but my teacher said it was incorrect. I don't know what is the correct answer for this one. Civics Which of the following is NOT part of the naturalization process? a. Filing a Declaration of Intention b. Taking a US history, gov't, or English language class c. Living in the US for 10 years d. Taking an Oath Civics health, safety, and moral standards of the community Civics I chose Letter D, but my teacher also said that it was incorrect. Civics Our rights are sometimes restricted in order to protect: a. those that are offended easily b. health, safety, and moral standards of the community c. the government from being overthrown d. individual rights History To become a law, typically a bill must be approved by: a. The House of Representatives, the Senate, and the President b. The House of Representatives c. The Senate d. The Supreme Court I chose Letter A, but someone how my teacher said it was incorrect. I was completely shocked... 1. Pages: 2. 1 3. 2 4. 3 5. 4 6. 5 7. 6 8. 7 9. 8 10. 9 11. 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http://aliquote.org/micro/2019-05-25-20-11-02/	# aliquot ## < a quantity that can be divided into another a whole number of time /> An ode to DEK and TeX: The Lingua Franca of LaTeX (via HN).	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8660385608673096, "perplexity": 3502.3361432363313}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-05/segments/1579250614086.44/warc/CC-MAIN-20200123221108-20200124010108-00347.warc.gz"}
http://hiflytech.com/cannot-create/cannot-create-var-lib-dhcp3-dhclient-eth0-leases.html	## How To Repair Cannot Create /var/lib/dhcp3/dhclient.eth0.leases Tutorial Home > Cannot Create > Cannot Create /var/lib/dhcp3/dhclient.eth0.leases # Cannot Create /var/lib/dhcp3/dhclient.eth0.leases aceperry (perrychow) wrote on 2008-03-31: #19 SOLVED! May 8 09:39:00 cia dhclient: DHCPACK of 10.10.10.11 from 10.10.10.1 May 8 09:39:00 cia dhclient: can't create /var/lib/dhcp3/dhclient.eth0.leases: Permission denied May 8 09:39:00 cia dhclient: bound to 10.10.10.11 -- renewal in Changed in dhcp3: status: Fix Released → Confirmed Ricardo Pérez López (ricardo) wrote on 2006-05-07: #8 Mmmm... We need to check that we now create /var/lib/dhclient/dhclient-eth0.conf and that file is used by the DHCP client. http://hiflytech.com/cannot-create/cannot-create-var-lib-dhcp3-dhclient-leases-permission-denied.html Perhaps Charlie is willing to bless this or come up with an alternative. Forums . UNIX is a registered trademark of The Open Group. The difference in name may be due to the system having 2 network cards. It will lease an IP address for 600 seconds if the client doesn't ask for a specific time frame. The directory is owned by root, so it might be that if your directory is empty, then dhclient isn't able to write to it. Join them; it only takes a minute: Sign up Here's how it works: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the Just delete the file and restart networkmanager. /var/lib/dhcp/dhclient.leases This is where the leases are stored, in my computer. Martin Pitt (pitti) wrote on 2006-12-12: #13 Never saw this here, but I'll try with Steve Johnson's recipe. In the end, what I did was to create the file /var/lib/dhcp3/dhclient.eth0.leases on the problem box. shouldn't ownership get assignment for this kind of stuff be during installation, och network configuration? I have tried: flushing current lease with dhclient -r, disconnecting the current Network Manager connection; killing any leftover dhclient and dnsmasq processes; cleaning /var/lib/dhcp/ directory, which supposedly contains the client lease Adv Reply May 25th, 2008 #2 Gunman1982 View Profile View Forum Posts Private Message Tea Glorious Tea! Changed in dhcp3: status: In Progress → Fix Released Kay Abendroth (kabendroth) wrote on 2008-08-05: #29 But this should be fixed in an LTS release also! Please try setting sme as a dhcp client and see if the dhclient config file gets expanded in the right place and sme gets an address. click The entry in dhcp.leases for 192.168.1.107 was then removed manually. Browse other questions tagged networking dhcp readonly etc or ask your own question. Comment 5 Guillaume Rousse 2013-03-02 15:31:19 CET Fixed with the switch to network manager 0.9.8. I have started to read server logs, and find a lot of following error: dhclient: can't create /var/lib/dhcp3/dhclient.eth0.leases: Permission denied What does it mean, and how to fix it? Wien's oscillator - amplitude stabilization with Zeners (loop's gain) Storage of a material that passes through non-living matter Why does Friedberg say that the role of the determinant is less central This site is not affiliated with Linus Torvalds or The Open Group in any way. Many logged entries to that affect (no success reported). VERIFICATION = Environment: sme8b6 from CD - clean = Current version installed: [root@test8b6 ~]# rpm -qa e-smith-base e-smith-base-5.2.0-28.el5.sme = Original problem: a) I think it'd be cleaner to use /var/lib/dhcpd for We don't need to move any files for dhclient as there isn't anything stored that we can't regen from a template.Please try setting sme as a dhcp client and see if Regardless, it still isn't resolved in 11.10, so . . . http://hiflytech.com/cannot-create/cannot-create-cfp.html In 9.04, the same command results in: [email protected]:/var/run$sudo dhcpd3 -d eth1 [sudo] password for martin: Internet Systems Consortium DHCP Server V3.1.1 Copyright 2004-2008 Internet Systems Consortium. Additional info: /var/lib/dhcp does not exist, but /var/lib/dhclient is created by dhclient rpm. Did you execute 'sudo dhclient' or just 'dhclient'? Comment 3 Jonathan 2010-03-11 09:48:20 CET (In reply to comment #2) > I notice that /var/lib/dhcp is not owned by any package in SME8. The issue is that the dhcp3-client is pointing to a directory that doesn't exist (or hasn't been created by the installation)or that the original ifup command is wrong. Do you want to help us debug the posting issues ? < is the place to report it, thanks ! http://hiflytech.com/cannot-create/cannot-create-var-state-dhcp-dhclient-leases.html Comment 6 Shad L. Now bring the interface back up by typing ifup eth0. Dhcpd was installed as part of setup along with bind9 and many other packages. Jörg Frings-Fürst (jff-de) wrote on 2008-08-05: #30 Why no fix in 8.04 which is LTS ? ## Affecting: isc-dhcp (Ubuntu) Filed here by: Neil Wilson When: 2011-12-05 Completed: 2012-05-28 Target Distribution Baltix BOSS Juju Charms Collection Elbuntu Guadalinex Guadalinex Edu Kiwi Linux nUbuntu PLD Linux Tilix tuXlab Ubuntu Sorry for crossposting, I put this in another thread somewhere, but this problem was driving me nuts until I fixed it. How do I change thickness and color of \hline on a table simultaneously؟ more hot questions question feed about us tour help blog chat data legal privacy policy work here advertising Short story about a human entering a large alien creature, inside of which is a whole ecosystem How did early mathematicians make it without Set theory? Wrote 0 leases to leases file. If you need to specify a WINS server for your Windows clients, you will need to include the netbios-name-servers option, e.g. Comment 4 Guillaume Rousse 2013-02-06 23:15:38 CET According to get_dhclient_leasefile function in nm-dhcp-dhclient.c code, NetworkManager should uses its own NMSTATEDIRstate directory to store dhclient leases files. Note You need to log in before you can comment on or make changes to this bug. http://hiflytech.com/cannot-create/cannot-create-tmp-cvs.html Adv Reply June 25th, 2008 #6 Krillin View Profile View Forum Posts Private Message Visit Homepage First Cup of Ubuntu Join Date Jun 2008 Location In a home BeansHidden! Changed in dhcp3: status: Incomplete → Confirmed Martin Pitt (pitti) on 2008-06-16 Changed in dhcp3: status: Confirmed → In Progress Launchpad Janitor (janitor) wrote on 2008-06-17: #25 Download full text (7.8 Edit bug mail Other bug subscribers Subscribe someone else Bug attachments Dependencies.txt (edit) Add attachment • Take the tour • Read the guide © 2004-2016 CanonicalLtd. • Terms of use Dec 3 09:33:55 OSIEDLE dhclient: DHCPDISCOVER on eth1 to 255.255.255.255 port 67 interval 4 Dec 3 09:33:55 OSIEDLE dhclient: DHCPOFFER from 192.168.0.2 Dec 3 09:33:55 OSIEDLE dhclient: DHCPREQUEST on eth1 to That bug should also move any existing dhcpd leases file to the new location, to deal smoothly with the upgrade case (it's not a good idea to forget all the outstanding For more information, see interfaces(5). # The loopback network interface auto lo iface lo inet loopback # The primary network interface auto eth0 iface eth0 inet dhcp ====$ cat /etc/dhcp3/dhclient.conf initscripts needs to be updated to use /var/lib/dhclient instead of /var/lib/dhcp - this initscripts change is forthcoming. But even after these steps I see in the logs DHCPDISCOVER immediately followed by DHCPREQUEST of somehow still remembered address. Code: can't create /var/lib/dhcp3/dhcpclient.leases can't create /var/run/dhcpclient.pid drop_proviliges: could not get group id: operation not permitted After I did a "sudo dhclient" all went ok, well kinda. Eventually the error on the bug was logged. It could do, but is unlikely to. The network information was changed to static and the interface was restarted with /etc/init.d/networking restart. drwxr-xr-x 23 root root 4.0K 2008-05-07 19:46 .. -rw-r--r-- 1 root root 0 2008-05-06 14:27 dhclient.leases I just cant see that the process ever would be able to write to that Any help from the community? ifup command: Code: dhclient3 -e IF_METRIC=100 -pf /var/run/dhclient.eth0.pid -lf /var/lib/dhcp3/dhclient.eth0.leases -1 eth0 One workaround (assuming you have root privileges and that the original dhcp client is being run under root user If you will use eth0 for providing addresses in the 192.168.1.x subnet then you should assign for instance ip 192.168.1.1 to the eth0 interface using NetworkManager.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.180404394865036, "perplexity": 7581.169364430107}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-09/segments/1518891814827.46/warc/CC-MAIN-20180223174348-20180223194348-00410.warc.gz"}
http://blog.cdmansfield.com/tag/partial-derivatives/	February 14, 2012 Tagged with: , , When I took my process thermodynamics course as an undergraduate student, I was told to use what I had initially considered to be a completely redundant notation for partial derivatives for thermodynamic potentials. The notation involved wrapping the partial derivative in a set of parentheses and noting which variables were “held constant” as a subscript. Ex. $\displaystyle\left(\frac{\partial P}{\partial V}\right)_{T,\vec{N}}$ The derivation leading to this was woefully devoid of the mathematical basis for this apparently redundant notation. Furthermore, so was the general literature on the subject, most of which consisted of fleeting introductions to their respective application. As I played with the idea, it became clear why this notation was indeed very necessary. It was only as I was solving a separate problem on my own that such notation yielded valuable information about the nature of the potentials being described.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 1, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9191372990608215, "perplexity": 608.0808167406663}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-09/segments/1550247489425.55/warc/CC-MAIN-20190219061432-20190219083432-00251.warc.gz"}
https://educatingphysics.com/gcse/electricity/experimenting-with-resistance/	Objectives: • To be able to define resistance • To be able to select and use the equation for resistance $R = \frac{V}{I}$ • To state and use Ohm’s law • To describe the I–V characteristics of a resistor at constant temperature and a bulb where the temperature varies (the bulb will largely will covered in the next lesson) Resistors serve a vital role in electronic circuits, and that is to limit the amount of current flowing through the circuits. The larger the resistance the stronger resistance there is to the flow of electrons. During this lesson you will have worked on trying to investigate the difference between a number of different unknown resistors. In order to do this we set up the diagram as shown below; For each resistor placed in the circuit, the voltage supplied was varied and a number of results were recorded. The following is a document showing these results which can be used for your some practice if you did not record a sufficient amount of data.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 2, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8621037006378174, "perplexity": 432.6080148522625}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-10/segments/1581875146643.49/warc/CC-MAIN-20200227002351-20200227032351-00383.warc.gz"}
https://pythonprogramming.net/crypto-rnn-model-deep-learning-python-tensorflow-keras/	Cryptocurrency-predicting RNN Model - Deep Learning basics with Python, TensorFlow and Keras p.11 Cryptocurrency RNN p.4 - Deep Learning basics with Python, TensorFlow and Keras p.11 Welcome to the next tutorial covering deep learning with Python, Tensorflow, and Keras. We've been working on a cryptocurrency price movement prediction recurrent neural network, focusing mainly on the pre-processing that we've got to do. In this tutorial, we're going to be finishing up by building our model and training it. Code up to this point: import numpy as np import pandas as pd import random from collections import deque from sklearn import preprocessing SEQ_LEN = 60 # how long of a preceeding sequence to collect for RNN FUTURE_PERIOD_PREDICT = 3 # how far into the future are we trying to predict? RATIO_TO_PREDICT = "LTC-USD" def classify(current, future): if float(future) > float(current): # if the future price is higher than the current, that's a buy, or a 1 return 1 else: # otherwise... it's a 0! return 0 def preprocess_df(df): df = df.drop("future", 1) # don't need this anymore. for col in df.columns: # go through all of the columns if col != "target": # normalize all ... except for the target itself! df[col] = df[col].pct_change() # pct change "normalizes" the different currencies (each crypto coin has vastly diff values, we're really more interested in the other coin's movements) df.dropna(inplace=True) # remove the nas created by pct_change df[col] = preprocessing.scale(df[col].values) # scale between 0 and 1. df.dropna(inplace=True) # cleanup again... jic. sequential_data = [] # this is a list that will CONTAIN the sequences prev_days = deque(maxlen=SEQ_LEN) # These will be our actual sequences. They are made with deque, which keeps the maximum length by popping out older values as new ones come in for i in df.values: # iterate over the values prev_days.append([n for n in i[:-1]]) # store all but the target if len(prev_days) == SEQ_LEN: # make sure we have 60 sequences! sequential_data.append([np.array(prev_days), i[-1]]) # append those bad boys! random.shuffle(sequential_data) # shuffle for good measure. buys = [] # list that will store our buy sequences and targets sells = [] # list that will store our sell sequences and targets for seq, target in sequential_data: # iterate over the sequential data if target == 0: # if it's a "not buy" sells.append([seq, target]) # append to sells list elif target == 1: # otherwise if the target is a 1... random.shuffle(sells) # shuffle the sells! lower = min(len(buys), len(sells)) # what's the shorter length? buys = buys[:lower] # make sure both lists are only up to the shortest length. sells = sells[:lower] # make sure both lists are only up to the shortest length. random.shuffle(sequential_data) # another shuffle, so the model doesn't get confused with all 1 class then the other. X = [] y = [] for seq, target in sequential_data: # going over our new sequential data X.append(seq) # X is the sequences return np.array(X), y # return X and y...and make X a numpy array! main_df = pd.DataFrame() # begin empty ratios = ["BTC-USD", "LTC-USD", "BCH-USD", "ETH-USD"] # the 4 ratios we want to consider for ratio in ratios: # begin iteration ratio = ratio.split('.csv')[0] # split away the ticker from the file-name dataset = f'training_datas/{ratio}.csv' # get the full path to the file. df = pd.read_csv(dataset, names=['time', 'low', 'high', 'open', 'close', 'volume']) # read in specific file # rename volume and close to include the ticker so we can still which close/volume is which: df.rename(columns={"close": f"{ratio}_close", "volume": f"{ratio}_volume"}, inplace=True) df.set_index("time", inplace=True) # set time as index so we can join them on this shared time df = df[[f"{ratio}_close", f"{ratio}_volume"]] # ignore the other columns besides price and volume if len(main_df)==0: # if the dataframe is empty main_df = df # then it's just the current df else: # otherwise, join this data to the main one main_df = main_df.join(df) main_df.fillna(method="ffill", inplace=True) # if there are gaps in data, use previously known values main_df.dropna(inplace=True) #print(main_df.head()) # how did we do?? main_df['future'] = main_df[f'{RATIO_TO_PREDICT}_close'].shift(-FUTURE_PERIOD_PREDICT) main_df['target'] = list(map(classify, main_df[f'{RATIO_TO_PREDICT}_close'], main_df['future'])) main_df.dropna(inplace=True) ## here, split away some slice of the future data from the main main_df. times = sorted(main_df.index.values) last_5pct = sorted(main_df.index.values)[-int(0.05len(times))] validation_main_df = main_df[(main_df.index >= last_5pct)] main_df = main_df[(main_df.index < last_5pct)] train_x, train_y = preprocess_df(main_df) validation_x, validation_y = preprocess_df(validation_main_df) print(f"train data: {len(train_x)} validation: {len(validation_x)}") BTC-USD LTC-USD BCH-USD ETH-USD train data: 77922 validation: 3860 Let's make a few more constants: import time EPOCHS = 10 # how many passes through our data BATCH_SIZE = 64 # how many batches? Try smaller batch if you're getting OOM (out of memory) errors. NAME = f"{SEQ_LEN}-SEQ-{FUTURE_PERIOD_PREDICT}-PRED-{int(time.time())}" # a unique name for the model Next let's build the model, first we need some imports: import tensorflow as tf from tensorflow.keras.models import Sequential from tensorflow.keras.layers import Dense, Dropout, LSTM, CuDNNLSTM, BatchNormalization from tensorflow.keras.callbacks import TensorBoard from tensorflow.keras.callbacks import ModelCheckpoint Now for the model. I tried a few things like 2 vs 3 layers, 64 vs 128 nodes, and found the following to begin to work: model = Sequential() model.add(BatchNormalization()) #normalizes activation outputs, same reason you want to normalize your input data. Model compile settings: opt = tf.keras.optimizers.Adam(lr=0.001, decay=1e-6) # Compile model model.compile( loss='sparse_categorical_crossentropy', optimizer=opt, metrics=['accuracy'] ) TensorBoard callback: tensorboard = TensorBoard(log_dir="logs/{}".format(NAME)) Next, let's check out the ModelCheckpoint callback filepath = "RNN_Final-{epoch:02d}-{val_acc:.3f}" # unique file name that will include the epoch and the validation acc for that epoch checkpoint = ModelCheckpoint("models/{}.model".format(filepath, monitor='val_acc', verbose=1, save_best_only=True, mode='max')) # saves only the best ones Train the model: # Train model history = model.fit( train_x, train_y, batch_size=BATCH_SIZE, epochs=EPOCHS, validation_data=(validation_x, validation_y), callbacks=[tensorboard, checkpoint], ) Run evaluations: # Score model score = model.evaluate(validation_x, validation_y, verbose=0) print('Test loss:', score[0]) print('Test accuracy:', score[1]) # Save model model.save("models/{}".format(NAME)) Full code up to this point and running it: import pandas as pd from collections import deque import random import numpy as np import tensorflow as tf from tensorflow.keras.models import Sequential from tensorflow.keras.layers import Dense, Dropout, LSTM, CuDNNLSTM, BatchNormalization from tensorflow.keras.callbacks import TensorBoard from tensorflow.keras.callbacks import ModelCheckpoint, ModelCheckpoint import time from sklearn import preprocessing SEQ_LEN = 60 # how long of a preceeding sequence to collect for RNN FUTURE_PERIOD_PREDICT = 3 # how far into the future are we trying to predict? RATIO_TO_PREDICT = "LTC-USD" EPOCHS = 10 # how many passes through our data BATCH_SIZE = 64 # how many batches? Try smaller batch if you're getting OOM (out of memory) errors. NAME = f"{SEQ_LEN}-SEQ-{FUTURE_PERIOD_PREDICT}-PRED-{int(time.time())}" def classify(current, future): if float(future) > float(current): # if the future price is higher than the current, that's a buy, or a 1 return 1 else: # otherwise... it's a 0! return 0 def preprocess_df(df): df = df.drop("future", 1) # don't need this anymore. for col in df.columns: # go through all of the columns if col != "target": # normalize all ... except for the target itself! df[col] = df[col].pct_change() # pct change "normalizes" the different currencies (each crypto coin has vastly diff values, we're really more interested in the other coin's movements) df.dropna(inplace=True) # remove the nas created by pct_change df[col] = preprocessing.scale(df[col].values) # scale between 0 and 1. df.dropna(inplace=True) # cleanup again... jic. sequential_data = [] # this is a list that will CONTAIN the sequences prev_days = deque(maxlen=SEQ_LEN) # These will be our actual sequences. They are made with deque, which keeps the maximum length by popping out older values as new ones come in for i in df.values: # iterate over the values prev_days.append([n for n in i[:-1]]) # store all but the target if len(prev_days) == SEQ_LEN: # make sure we have 60 sequences! sequential_data.append([np.array(prev_days), i[-1]]) # append those bad boys! random.shuffle(sequential_data) # shuffle for good measure. buys = [] # list that will store our buy sequences and targets sells = [] # list that will store our sell sequences and targets for seq, target in sequential_data: # iterate over the sequential data if target == 0: # if it's a "not buy" sells.append([seq, target]) # append to sells list elif target == 1: # otherwise if the target is a 1... random.shuffle(sells) # shuffle the sells! lower = min(len(buys), len(sells)) # what's the shorter length? buys = buys[:lower] # make sure both lists are only up to the shortest length. sells = sells[:lower] # make sure both lists are only up to the shortest length. random.shuffle(sequential_data) # another shuffle, so the model doesn't get confused with all 1 class then the other. X = [] y = [] for seq, target in sequential_data: # going over our new sequential data X.append(seq) # X is the sequences return np.array(X), y # return X and y...and make X a numpy array! main_df = pd.DataFrame() # begin empty ratios = ["BTC-USD", "LTC-USD", "BCH-USD", "ETH-USD"] # the 4 ratios we want to consider for ratio in ratios: # begin iteration ratio = ratio.split('.csv')[0] # split away the ticker from the file-name print(ratio) dataset = f'training_datas/{ratio}.csv' # get the full path to the file. df = pd.read_csv(dataset, names=['time', 'low', 'high', 'open', 'close', 'volume']) # read in specific file # rename volume and close to include the ticker so we can still which close/volume is which: df.rename(columns={"close": f"{ratio}_close", "volume": f"{ratio}_volume"}, inplace=True) df.set_index("time", inplace=True) # set time as index so we can join them on this shared time df = df[[f"{ratio}_close", f"{ratio}_volume"]] # ignore the other columns besides price and volume if len(main_df)==0: # if the dataframe is empty main_df = df # then it's just the current df else: # otherwise, join this data to the main one main_df = main_df.join(df) main_df.fillna(method="ffill", inplace=True) # if there are gaps in data, use previously known values main_df.dropna(inplace=True) #print(main_df.head()) # how did we do?? main_df['future'] = main_df[f'{RATIO_TO_PREDICT}_close'].shift(-FUTURE_PERIOD_PREDICT) main_df['target'] = list(map(classify, main_df[f'{RATIO_TO_PREDICT}_close'], main_df['future'])) main_df.dropna(inplace=True) ## here, split away some slice of the future data from the main main_df. times = sorted(main_df.index.values) last_5pct = sorted(main_df.index.values)[-int(0.05len(times))] validation_main_df = main_df[(main_df.index >= last_5pct)] main_df = main_df[(main_df.index < last_5pct)] train_x, train_y = preprocess_df(main_df) validation_x, validation_y = preprocess_df(validation_main_df) print(f"train data: {len(train_x)} validation: {len(validation_x)}") model = Sequential() # Compile model model.compile( loss='sparse_categorical_crossentropy', optimizer=opt, metrics=['accuracy'] ) tensorboard = TensorBoard(log_dir="logs/{}".format(NAME)) filepath = "RNN_Final-{epoch:02d}-{val_acc:.3f}" # unique file name that will include the epoch and the validation acc for that epoch checkpoint = ModelCheckpoint("models/{}.model".format(filepath, monitor='val_acc', verbose=1, save_best_only=True, mode='max')) # saves only the best ones # Train model history = model.fit( train_x, train_y, batch_size=BATCH_SIZE, epochs=EPOCHS, validation_data=(validation_x, validation_y), callbacks=[tensorboard, checkpoint], ) # Score model score = model.evaluate(validation_x, validation_y, verbose=0) print('Test loss:', score[0]) print('Test accuracy:', score[1]) # Save model model.save("models/{}".format(NAME)) BTC-USD LTC-USD BCH-USD ETH-USD BTC-USD LTC-USD BCH-USD ETH-USD train data: 77922 validation: 3860 Train on 77922 samples, validate on 3860 samples Epoch 1/10 77922/77922 [==============================] - 22s 287us/step - loss: 0.7147 - acc: 0.5248 - val_loss: 0.6865 - val_acc: 0.5425 Epoch 2/10 77922/77922 [==============================] - 20s 257us/step - loss: 0.6862 - acc: 0.5490 - val_loss: 0.6833 - val_acc: 0.5547 Epoch 3/10 77922/77922 [==============================] - 20s 255us/step - loss: 0.6829 - acc: 0.5600 - val_loss: 0.6766 - val_acc: 0.5661 Epoch 4/10 77922/77922 [==============================] - 20s 256us/step - loss: 0.6809 - acc: 0.5639 - val_loss: 0.6802 - val_acc: 0.5715 Epoch 5/10 77922/77922 [==============================] - 20s 257us/step - loss: 0.6796 - acc: 0.5679 - val_loss: 0.6737 - val_acc: 0.5744 Epoch 6/10 77922/77922 [==============================] - 20s 257us/step - loss: 0.6778 - acc: 0.5718 - val_loss: 0.6720 - val_acc: 0.5845 Epoch 7/10 77922/77922 [==============================] - 20s 256us/step - loss: 0.6751 - acc: 0.5761 - val_loss: 0.6673 - val_acc: 0.5798 Epoch 8/10 77922/77922 [==============================] - 20s 256us/step - loss: 0.6716 - acc: 0.5827 - val_loss: 0.6751 - val_acc: 0.5692 Epoch 9/10 77922/77922 [==============================] - 20s 259us/step - loss: 0.6677 - acc: 0.5912 - val_loss: 0.6694 - val_acc: 0.5795 Epoch 10/10 77922/77922 [==============================] - 20s 256us/step - loss: 0.6615 - acc: 0.6016 - val_loss: 0.6727 - val_acc: 0.5775 Test loss: 0.67270497590149 Test accuracy: 0.5774611397728401 Not a bad start. Better than random, validation accuracy rises over time, validation loss drops. Changing the name constant to include the ratio we're predicting: NAME = f"{RATIO_TO_PREDICT}-{SEQ_LEN}-SEQ-{FUTURE_PERIOD_PREDICT}-PRED-{int(time.time())}" And then testing against all of the ratios: Looks pretty good. Use at your own risk, there are probably bugs. Finance is hard. Historical results are not indicative of future results. This is for educational use only. ... you get the idea! That's all for this project. The next tutorial: • Introduction to Deep Learning - Deep Learning basics with Python, TensorFlow and Keras p.1 • Convolutional Neural Networks - Deep Learning basics with Python, TensorFlow and Keras p.3 • Analyzing Models with TensorBoard - Deep Learning basics with Python, TensorFlow and Keras p.4 • Optimizing Models with TensorBoard - Deep Learning basics with Python, TensorFlow and Keras p.5 • How to use your trained model - Deep Learning basics with Python, TensorFlow and Keras p.6 • Recurrent Neural Networks - Deep Learning basics with Python, TensorFlow and Keras p.7 • Creating a Cryptocurrency-predicting finance recurrent neural network - Deep Learning basics with Python, TensorFlow and Keras p.8 • Normalizing and creating sequences for our cryptocurrency predicting RNN - Deep Learning basics with Python, TensorFlow and Keras p.9 • Balancing Recurrent Neural Network sequence data for our crypto predicting RNN - Deep Learning basics with Python, TensorFlow and Keras p.10 • Cryptocurrency-predicting RNN Model - Deep Learning basics with Python, TensorFlow and Keras p.11	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.15123574435710907, "perplexity": 15182.06781202737}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610703530835.37/warc/CC-MAIN-20210122144404-20210122174404-00096.warc.gz"}
https://www.gradesaver.com/textbooks/math/calculus/calculus-8th-edition/chapter-14-partial-derivatives-14-1-functions-of-several-variables-14-1-exercises-page-942/61	## Calculus 8th Edition This function is presented on the graph $C$ and its level curves are on the graph II. This is because this function is periodical in the product of $xy$. This product grows most rapidly along the lines $x=y$ and $x=-y$ and we see that this function oscillates with greatest frequency along these lines. This is also reflected on the graph II because there the level curves get denser along the mentioned lines.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8544350862503052, "perplexity": 267.9227816694222}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-30/segments/1531676589222.18/warc/CC-MAIN-20180716060836-20180716080836-00199.warc.gz"}
https://cs.stackexchange.com/help/badges/3?page=7	# Help Center > Badges > Editor First edit. Awarded 10318 times Awarded Mar 20 at 18:10 Awarded Mar 20 at 16:20 Awarded Mar 20 at 15:35 Awarded Mar 20 at 11:25 Awarded Mar 20 at 7:55 Awarded Mar 20 at 7:10 Awarded Mar 20 at 3:40 (post deleted or otherwise unavailable) Awarded Mar 19 at 19:50 Awarded Mar 19 at 16:00 Awarded Mar 19 at 10:55 Awarded Mar 19 at 8:20 Awarded Mar 19 at 8:10 Awarded Mar 19 at 7:30 (post deleted or otherwise unavailable) Awarded Mar 19 at 5:00 Awarded Mar 19 at 3:45 (post deleted or otherwise unavailable) Awarded Mar 19 at 3:40 Awarded Mar 19 at 3:05 Awarded Mar 18 at 23:30 Awarded Mar 18 at 23:00 Awarded Mar 18 at 15:20 (post deleted or otherwise unavailable) Awarded Mar 18 at 14:20 Awarded Mar 18 at 9:25 Awarded Mar 17 at 20:40 (post deleted or otherwise unavailable) Awarded Mar 17 at 20:20 Awarded Mar 16 at 23:25 Awarded Mar 16 at 16:50 Awarded Mar 16 at 16:25 Awarded Mar 16 at 14:00 Awarded Mar 16 at 9:45 Awarded Mar 16 at 1:35 Awarded Mar 15 at 22:45 Awarded Mar 15 at 18:35 Awarded Mar 15 at 9:00 Awarded Mar 15 at 8:25 (post deleted or otherwise unavailable) Awarded Mar 15 at 7:35 Awarded Mar 14 at 17:10 Awarded Mar 14 at 16:55 Awarded Mar 14 at 14:50 Awarded Mar 14 at 10:10 Awarded Mar 14 at 3:10 Awarded Mar 13 at 21:25 Awarded Mar 13 at 21:05 Awarded Mar 13 at 19:40 Awarded Mar 13 at 19:15 Awarded Mar 13 at 4:25 Awarded Mar 13 at 3:35 Awarded Mar 13 at 2:20 (post deleted or otherwise unavailable) Awarded Mar 13 at 1:15 Awarded Mar 12 at 16:15 (post deleted or otherwise unavailable) Awarded Mar 12 at 15:50 (post deleted or otherwise unavailable) Awarded Mar 12 at 12:50 Awarded Mar 12 at 12:25 (post deleted or otherwise unavailable) Awarded Mar 12 at 12:20 Awarded Mar 12 at 11:45 (post deleted or otherwise unavailable) Awarded Mar 12 at 8:05 Awarded Mar 12 at 7:30 Awarded Mar 12 at 5:05 Awarded Mar 12 at 4:10 Awarded Mar 11 at 22:10 Awarded Mar 11 at 20:00	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9252583980560303, "perplexity": 14361.355145638801}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-22/segments/1558232257699.34/warc/CC-MAIN-20190524164533-20190524190533-00357.warc.gz"}
https://phys.libretexts.org/Bookshelves/Astronomy_and_Cosmology_TextMaps/Map%3A_Stellar_Atmospheres_(Tatum)/7%3A_Atomic_Spectroscopy/7.13%3A_LS-coupling	$$\require{cancel}$$ # 7.13: LS-coupling Each of the several electrons in an atom has an orbital angular momentum $$\textbf{l}$$ and a spin angular momentum $$\textbf{s}$$, and there are numerous conceivable ways in which the various angular momenta can be coupled together to result in the total electronic angular momentum of the atom. (The total angular momentum of the atom may also include a small contribution from the nucleus. This contribution is usually quite tiny, but measurable. We'll ignore it for the time being; in any case, many nuclides (including most of those that have even numbers of protons and neutrons) have zero nuclear spin. One of the simplest coupling schemes is called LS-coupling (or sometimes Russell-Saunders coupling). In this scheme (which may be regarded as one extreme of a host of conceivable coupling schemes), all the orbital angular momenta $$\textbf{l}$$ of the several electrons are strongly coupled together to form the total electronic orbital angular momentum of the atom, which is denoted by $$\textbf{L}$$. This can be represented symbolically by $\sum{\textbf{I}}= \textbf{L} . \label{7.13.1} \tag{7.13.1}$ The summation indicated is a vector summation. The magnitude of $$\textbf{L}$$ is $$\sqrt{L(L+1)} \hbar$$, and $$L$$ can have nonnegative integral values, 0, 1, 2, 3, etc. Similarly, all the spin angular momenta $$\textbf{s}$$ of the several electrons are strongly coupled together to form the total electronic spin angular momentum of the atom, which is denoted by $$\textbf{S}$$. This can be represented symbolically by $\sum{\textbf{s}} = \textbf{S} \label{7.13.2} \tag{7.13.2}$ The magnitude of $$\textbf{S}$$ is $$\sqrt{S(S+1)}\hbar$$. If there is an even number of electrons in the atom, $$S$$ can have nonnegative integral values. If there is an odd number of electrons in the atoms, the value of S is a positive odd integral number times $$1/2$$, such as $$1/2, \ 3/2, \ 5/2$$,… etc. The total electronic orbital angular momentum of the atom, $$\textbf{L}$$, then couples weakly to the total electronic spin angular momentum of the atom, $$\textbf{S}$$, to form the total (orbital plus spin) electronic angular momentum of the atom, denoted by $$\textbf{J}$$. This is denoted symbolically by $\textbf{L} + \textbf{S} = \textbf{J} \label{7.13.3} \tag{7.13.3}$ The magnitude of $$\textbf{J}$$ is $$\sqrt{J(J+1)}\hbar$$. If there is an even number of electrons, $$J$$ can take any of the $$2 \ \text{min}\left\{ L , S\right\} + 1$$ nonnegative integral values from $$\|L − S\|$$ to $$L + S$$. If there is an odd number of electrons, $$J$$ can have any of the $$2 \ \text{min} \left\{ L , S \right\} + 1$$ odd-half-integral values from $$\|L − S \|$$ to $$L + S$$. The $$z$$-component of $$\textbf{J}$$ is $$M \hbar$$. If $$J$$ is integral (i.e. if there is an even number of electrons), $$M$$ can have any of the $$2J+1$$ integral values from $$−J$$ to $$+J$$. If $$J$$ is odd-half-integral, $$M$$ can have any of the $$2J+1$$ odd-half-integral values from $$−J$$ to $$+J$$. In many of the lighter elements near the beginning of the periodic table, the coupling of the angular momenta is close to that of ideal $$LS$$-coupling. There are appreciable departures from this simple scheme higher up in the periodic table. We shall discuss other coupling schemes a little later.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9910230040550232, "perplexity": 173.28694294118455}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-04/segments/1547583745010.63/warc/CC-MAIN-20190121005305-20190121031305-00335.warc.gz"}
https://arxiv.org/abs/1103.4861	astro-ph.CO (what is this?) # Title: A cross-correlation study of the Fermi-LAT $γ$-ray diffuse extragalactic signal Abstract: In this work, starting from 21 months of data from the Fermi-Large Area Telescope, we derive maps of the residual isotropic gamma-ray emission, a relevant fraction of which is expected to be contributed by the extragalactic diffuse gamma-ray background. We compute the angular two-point auto-correlation function of the residual Fermi-LAT maps at energies E>1GeV, E>3GeV and E>30GeV well above the Galactic plane and find no significant correlation signal. This is, indeed, what is expected if the EGB were contributed by BL Lacertae, Flat Spectrum Radio Quasars or star-forming galaxies, since, in this case, the predicted signal is very weak. Then, we search for the Integrated Sachs-Wolfe signature by cross-correlating the Fermi-LAT maps with the WMAP7-Cosmic Microwave Background map. We find a cross-correlation consistent with zero, even though the expected signal is larger than that of the EGB auto-correlation. Finally, in an attempt to constrain the nature of the gamma-ray background we cross-correlate the Fermi-LAT maps with the angular distributions of objects that may contribute to the EGB: QSOs in the SDSS-DR6 catalog, NVSS galaxies, 2MASS galaxies and LRG in the SDSS catalog. The cross-correlation is always consistent with zero, in agreement with theoretical expectations, but we find (with low statistical significance) some interesting features that may indicate that some specific classes of objects contribute to the EGB. A chi2 analysis confirms that the correlation properties of the 21-month data do not provide strong constraints of the EGB origin. However, the results suggest that the situation will significantly improve with the 5- and 10-year Fermi-LAT data. The future EGB analysis will then allow placing significant constraints on the nature of the EGB and might provide in addition a detection of the ISW signal. (Abridged) Comments: 18 pages, 23 figures, 2 tables, MNRAS in press Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO) Journal reference: Mon. Not. Roy. Astron. Soc. 416, 2247-2264 (2011) DOI: 10.1111/j.1365-2966.2011.19200.x Cite as: arXiv:1103.4861 [astro-ph.CO] (or arXiv:1103.4861v2 [astro-ph.CO] for this version) ## Submission history From: Jun-Qing Xia [view email] [v1] Thu, 24 Mar 2011 20:00:04 GMT (3816kb) [v2] Wed, 7 Sep 2011 09:42:43 GMT (3843kb)	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7951414585113525, "perplexity": 4062.4275043778507}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-22/segments/1495463609605.31/warc/CC-MAIN-20170528062748-20170528082748-00120.warc.gz"}
http://physics.stackexchange.com/questions/2497/where-does-matter-come-from/2498	# Where does matter come from? I admit, it's been a few years since I've studied physics, but the following question came to me when I was listening to a talk by Lawrence Krauss. Is there any knowledge of from where matter that exists today originated? I recall that the law of conservation of mass asserts that matter cannot be created nor destroyed, but surely the matter we see today had to be created at some point? Perhaps I am applying this law in the wrong fashion. The reason I ask, is because Krauss mentioned that the elements of organic matter where created in stars, not at the beginning of time (whenever that may have been), but I ask, where did the building blocks for these elements arise? Were they too created in stars? If so, from where did their constituent building blocks come? Please forgive me if this off topic, it is my first post on this particular stackexchange site. Thank you. - The law of conservation of mass is only valid in the classical limit. More in general, the combination of mass and energy is conserved, as they can be exchanged under certain conditions $E=mc^2$. In very simplified terms, it is currently understood that, initially, possibly only energy was present. Then this energy started to partially change into mass, forming first quarks and electrons (mostly). Then heavier particles. Finally, once the universe cooled down a bit more, the first atoms started to form through the aggregation of the particles. It is calculated that atoms would be split between hydrogen and helium with a 3:1 ratio - these are the two lightest atoms. This was enough to create the first generation of stars, which with fusion and with their dying blast generated the heavier elements that build life. This explains the currently understood principle of nucleogenesis - if you are instead more interested in how and why energy is changed into mass, and what is the nature of mass, then space_cadet's answer gives you a quick overlook of the hypotheses that are being studied. - This is correct but you fail to mention the difficult corollary problem: given that pair creation processes are symmetric in Baryon and Lepton numbers, why is the observed universe almost entirely devoid of anti-matter? (To which there are no final answers as yet. CP violation may play a part.) – dmckee Jan 4 '11 at 4:31 "only energy was present" -> um, this part is horribly wrong. Initially (and always) there were some particles. The closer to Big Bang the higher the temperature and more massive particles you'll get. In particular, there was certainly quark-gluon plasma and a soup of heavier particles (most of which we probably don't know yet). One also needs to take into account the restoration of electroweak symmetry and perhaps grand unification. There were also lots of micro-BH and going even further probably other amusing objects of quantum gravity. – Marek Jan 4 '11 at 9:00 @dmckee: I left out that part purposefully. It's irrelevant to the question. – Sklivvz Jan 4 '11 at 10:08 This hints at the right physics, but the details are muddled. It doesn't make sense to talk about "only energy" being present; rather, there was a hot plasma of photons, electrons, quarks, gluons, and other particles. At the earliest times we have good evidence and understanding of, these were a plasma with a temperature on the order of 10 MeV. As it cooled, the plasma wasn't hot enough to split nuclei into free quarks and gluons. Nucleons formed then, as you mention. But before that, there was plenty of matter around, with more baryons than antibaryons (for unknown reasons). – Matt Reece Jan 5 '11 at 2:58 There is no such thing as "pure energy" whatever that means. Might as well call it "pure ectoplasm" while you're at it. In the context of modern cosmology you have to mention CP violation and the other two Sakharov conditions if you going to speak of the "origin of matter". Nucleogenesis itself doesn't tell you anything about the origin of electrons, protons or neutrinos. Those are the inputs for nucleogenesis. But where did these "inputs" arise from? Is there a simple, self-consistent explanation for their presence? – user346 Jan 5 '11 at 3:05 the conservation of energy is violated in cosmology - in all situations described by general relativity in which the time-translational symmetry of the "background" is broken. That's clearly the case of the Big Bang, too. Again: By Noether's theorem, the conservation of energy is linked to the time-translational symmetry (the properties of the Universe don't depend on time) which is broken in an expanding Universe. So one can see that the total energy/mass of the Universe is not conserved in time. In particular, the "dust" with zero pressure has a conserved total energy/mass. However, the energy carried by radiation - such as photons - decreases as $1/a$ - inverse linear size of the Universe - because the wavelength gets larger as well, which decreases the energy of each quantum. On the contrary, the energy/mass carried by the dark energy is increasing with the volume because the energy density is constant - that's why dark energy is the normal realization is known as the cosmological constant. The density is constant but the volume of space is growing: the total energy is growing, too. It is very likely that the huge mass of the Universe around us was created by inflation. During inflation, there was also a nonzero "dark energy" - energy density of the vacuum - which was constant while the volume of space was exponentially growing. This created lots of energy, and at the very end, a big part of the energy (kinetic energy of the inflaton which is proportional to the total energy etc.) was converted to ordinary particles that eventually gave rise to the galaxies etc. So the exponentially large mass of the Universe is a large, unnatural number, but this unnatural number is actually explained by inflation. As Alan Guth, the main father of inflation, said, the Universe is the ultimate free lunch. Best wishes Lubos - @ Luboš Motl. This is by far the best answer out of the three, not sure why it does not have more votes :( – stringpheno Feb 25 '11 at 5:59 @stringpheno: Possibly because the difficulty of contents are far beyond the level of the original question. It may be correct, but it's not clear to me that the original question asker will have gained anything from it. (Not that I am claiming that I could do half as well.) – Beska May 27 '11 at 14:27 The origin of matter is a major problem in modern physics. Sure we have a description in terms of the Standard Model of particle interactions, but that is simply an empirical framework built upon observation. There is no compelling reason, for instance, why the gauge group of the SM should be $SU(3)\times SU(2) \times U(1)$ and not any other. Grand Unified Theories (GUT) attempt to provide an answer which seemingly complicates the issue further by suggesting bigger groups $SO(5), SO(10), \ldots$ which can contain all three families of particles. Certain streams of contemporary research appear to favor an alternative and perhaps simpler approach, one that was favored by Einstein and Wheeler among others - that matter is simply another aspect of geometry. The paper of Einstein and Rosen which is commonly cited as the source of the notion of wormholes, was in fact an attempt to provide an explanation for particles as topological defects in the vacuum. Anyhow, all of this sounds pretty technical. To simplify the notion greatly the viewpoint favored by approaches such as Non-Commutative Geometry, LQG and (IMHO) String Theory is that particles are topological defects in a background geometry. If you think of geometry as a sheet then these defects can be thought of as punctures in this sheet. How such punctures can join up and interact should be governed by simple rules and one would hope these rules will yield the S.M. in a suitable coarse-grained approximation. Edit: Changing some wording in 2nd para to something a little less absolute in response to comments by @matt and others. - Sure they do. I have nothing against them. They just defeat the purposes of discussion. – user346 Jan 4 '11 at 5:16 Regarding string theory: various particles are just excitations of the strings so your statement amounts to saying that strings are topological defects. Even if this view could somehow be made correct (e.g. by interpreting open string attached to a brane as topological torus) I don't believe anyone holds such a view or that it is in any way useful. – Marek Jan 4 '11 at 9:09 I don't know what you mean by saying that bigger groups "contain all three families" of particles. The groups contain only gauge bosons; each generation of particles we know fits into some representation of these groups, but the generations are not unified. Also, I absolutely do not agree that research is "abandoning" field-theoretic ideas, which if nothing else are valid descriptions of low-energy physics. It's not at all clear to me in what sense either string theory or noncommutative geometry imply that matter is topological defects. – Matt Reece Jan 5 '11 at 4:17 Your statement was about what GUTs attempt to do. They don't attempt to unify families. The fact that Garrett Lisi does is neither here nor there; I'm not going to argue about the definition of "crackpot," but his theory made little sense and rather than try to understand the obvious criticisms he seems to keep writing papers on the same thing. At any rate, I think this site should have answers involving accepted physics, of which GUTs are an example and whatever Lisi is doing isn't. – Matt Reece Jan 5 '11 at 6:06 I was not referring to E8 which I could not care less about, just to your original answer. When a non-expert comes and ask a question, I'll let him know what is known with near certainty (the answer to this question has probably to do with reheating). I also like the idea of matter from geometry, and Wheeler's geons and all the rest, but the fact is that this idea currently plays no role in accepted mainstream theories, and in most research directions to extend them. That may change in the future, at which point it would be legitimate to include it in an answer. – user566 Jan 5 '11 at 15:44	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7629138231277466, "perplexity": 429.84018276263873}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-48/segments/1448398445080.12/warc/CC-MAIN-20151124205405-00122-ip-10-71-132-137.ec2.internal.warc.gz"}
https://crad.ict.ac.cn/CN/10.7544/issn1000-1239.20200547	ISSN 1000-1239 CN 11-1777/TP • 人工智能 • ### 结合双流网络和双向五元组损失的跨人脸-语音匹配 1. 1(华侨大学计算机科学与技术学院福建厦门 361021);2(综合业务网理论及关键技术国家重点实验室(西安电子科技大学) 西安 710071);3(厦门市计算机视觉与模式识别重点实验室(华侨大学) 福建厦门 361021);4(广西师范大学计算机科学与信息工程学院广西桂林 541004) ([email protected]) • 出版日期: 2022-03-07 • 基金资助: 国家自然科学基金项目(61673185,61922066,61972167)；综合业务网理论及关键技术国家重点实验室基金项目(ISN20-11)；福建省自然科学基金项目(2020J01084)；之江实验室开放课题(2021KH0AB01) ### Cross Face-Voice Matching via Double-Stream Networks and Bi-Quintuple Loss Liu Xin1,2,3, Wang Rui1,3, Zhong Bineng4, Wang Nannan2 1. 1(College of Computer Science and Technology, Huaqiao University, Xiamen, Fujian 361021);2(State Key Laboratory of Integrated Services Networks (Xidian University), Xi’an 710071);3(Xiamen Key Laboratory of Computer Vision and Pattern Recognition (Huaqiao University), Xiamen, Fujian 361021);4(School of Computer Science and Information Engineering, Guangxi Normal University, Guilin, Guangxi 541004) • Online: 2022-03-07 • Supported by: This work was supported by the National Natural Science Foundation of China (61673185, 61922066, 61972167), the Project of State Key Laboratory of Integrated Services Networks (ISN20-11), the Natural Science Foundation of Fujian Province (2020J01084), and the Zhejiang Laboratory (2021KH0AB01). Abstract: Facial information and voice cues are the most natural and flexible ways in human-computer interaction, and some recent researchers are now paying more attention to the intelligent cross-modal perception between the face and voice modalities. Nevertheless, most existing methods often fail to perform well on some challenge cross-modal face-voice matching tasks, mainly due to the complex integration of semantic gap and modality heterogeneity. In this paper, we address an efficient cross-modal face-voice matching network by using double-stream networks and bi-quintuple loss, and the derived feature representations can be well utilized to adapt four challenging cross-modal matching tasks between faces and voices. First, we introduce a novel modality-shared multi-modal weighted residual network to model the face-voice association, by embedding it on the top layer of our double-stream network. Then, a bi-quintuple loss is newly proposed to significantly improve the data utilization, while enhancing the generalization ability of network model. Further, we learn to predict identity (ID) of each person during the training process, which can supervise the discriminative feature learning process. As a result, discriminative cross-modal representations can be well learned for different matching tasks. Within four different cross-modal matching tasks, extensive experiments have shown that the proposed approach performs better than the state-of-the-art methods, by a large margin reaching up to 5%.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3449036777019501, "perplexity": 5458.019909811749}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-27/segments/1656103983398.56/warc/CC-MAIN-20220702010252-20220702040252-00752.warc.gz"}
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http://www.zora.uzh.ch/52154/	Quick Search: Browse by: Zurich Open Repository and Archive Permanent URL to this publication: http://dx.doi.org/10.5167/uzh-52154 # Benz, Men-Andri; Buehler, Stefan; Schmutzler, Armin (2000). Quality Provision in Deregulated Industries: The Railtrack Problem. Working paper series / Socioeconomic Institute No. 2, University of Zurich. Preview PDF 252kB ## Abstract This paper studies a network provider's incentives to invest in infrastructure quality. In a simple but general framework, we investigate how various institutional settings affect investment incentives. We show that under reasonable assumptions on demand, investment incentives are smaller under vertical separation than under vertical integration. We consider two strategies for improving investment incentives under vertical separation. First, the introduction of competition for the market can sometimes improve incentives. Second, with non-linear access prices investment incentives under separation become identical to those under integration.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8832793235778809, "perplexity": 13430.58497666651}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-22/segments/1464049276537.37/warc/CC-MAIN-20160524002116-00116-ip-10-185-217-139.ec2.internal.warc.gz"}
https://proofwiki.org/wiki/Book:Christopher_Clapham/The_Concise_Oxford_Dictionary_of_Mathematics/Third_Edition	# Book:Christopher Clapham/The Concise Oxford Dictionary of Mathematics/Third Edition Published $2005$, Oxford University Press.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7609291672706604, "perplexity": 29117.348374292007}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-10/segments/1581875145282.57/warc/CC-MAIN-20200220193228-20200220223228-00168.warc.gz"}
https://www.general-relativity.net/2018/07/commentary-22-xx3-is-c2-function.html	## Friday, 6 July 2018 ### Commentary 2.2 ф(x)=\|x^3\| is a C^2 function In section 2.2 on "What is a manifold?" under equation (2.8) he says ф(x)=\|x3\| is a C2 function because it is infinitely differentiable everywhere except at x=0 where it is differentiable twice but not three times. I had to think about that one and had a quick look at this video on the Khan academy to refresh my memory. I then got to use my own graph paper to test the assertion for myself. What fun! Now I have put it in Excel. Here is the result. ф(x)=\|x3\| is in blue. It's gradient is obviously negative for x<0 and positive for x>0. So For x<0, ф'=-3x2 and for x>=0 ф'=3x2. The gradient of ф' is always positive. So ф''=\|6x\|. We can now see the problem at x=0 in green. It is hardly necessary to plot ф''' which is -6 for x<0, 6 for x>0, but undefined at x=0. Resources	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8183627128601074, "perplexity": 1257.6364659841345}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-25/segments/1623487598213.5/warc/CC-MAIN-20210613012009-20210613042009-00326.warc.gz"}
http://www.gamedev.net/page/resources/_/technical/opengl/opengl-instancing-demystified-r3226	• Create Account Like 27Likes Dislike # OpenGL Instancing Demystified By Martin Thomas \| Published Aug 08 2013 09:20 AM in OpenGL Peer Reviewed by (slicer4ever, Dave Hunt, ivan.spasov) ogl opengl instancing When I tried to implement instancing some time ago, I found that nearly 0 tutorials/articles were written about it. Much like everything a bit beyond OpenGL 2.1, this seems to be a bit of a taboo among OpenGL programmers. Everyone knows about it, yet not many are actually using it despite it being easy to do. Not anymore. # Instancing for everyone ## History Instancing became a core feature of OpenGL starting with version 3.1 back in 2009, named ARB_draw_instanced. At this time you could only use Texture Buffer Objects (TBOs) or Uniform Buffer Objects (UBOs) to actually deliver your data into the shaders. A year later, in 2010, OpenGL 3.3 arrived with the brand new ARB_instanced_arrays extension now being a core feature. With this addition you could use actual Vertex Buffer Objects (VBOs) to deliver your data. Yay! There is a restriction to it however, you can only pass 16 vertex attributes to your vertex shader (by specification, or GL_MAX_VERTEX_ATTRIB_BINDINGS), which makes it 16 * vec4 = 64 float values. In 2010 ARB_draw_indirect (OpenGL 4.0) also made it to the core. It enables you to pass the parameters to the glDrawArrays* functions indirectly, that is from a piece of memory. In 2011 ARB_base_instance (OpenGL 4.2) became a core feature too. This allows you to specify a half-open range [x...y) of what instance data you would like to draw. To add ARB_transform_feedback_instanced was also added, that allows you to use the transform feedback data as instance data to draw. ## The Big Concept So when is it appropriate to use instancing? Well when you would like to draw the same thing thousand times. The reason to this is that a single draw call (glDraw) costs a lot of CPU power, as the driver needs to do some checking and preparation (magic!) before the function call would return. Usually on an average PC 2000 draw calls is the most you can do without hurting your frame rate too bad (remember: you have at max 33 ms per frame!). So drawing something 1000 times would make up half of your draw calls, and that is bad. Instancing solves this by allowing you to tell the driver: 'Hey, I'd like to draw this piece of geometry 1000 times'. But you would wind up with 1000 objects in the same place, right? To solve this, you can pass data that will be unique to each of the 1000 objects drawn. This is what I call 'Instance Data'. This is usually a (modelview) matrix, but for the sake of simplicity, I will only store one vec4 (position). ## Algorithm overview Normal rendering: For each frame: For each object: -upload object specific data to uniforms (or UBOs) -render the object Instancing: For each frame: For each object: -prepare instance data, store it in a buffer (no need to do this each frame if the buffer is static) -upload that buffer to the GPU -render the objects using instancing using the provided Instance Data You can clearly see that the number of draw calls is reduced from n to 1 (plus no uniform passing!). ## The implementation I'm going to use a small (~600 lines) framework I wrote for prototyping techniques. This allows me to hide irrelevant code. We are going to draw cubes. The first step to drawing cubes is to create a VBO that contains the vertex data. GLuint box = frm.create_box(); //Vertex Array Object (VAO) of the box Then we are going to create the VBO for the instance data: the positions of the cubes. To do this we need a buffer (memory) and a VBO. First let's bind the fresh VAO glBindVertexArray( box ); Then create the buffer vector<vec4> positions; positions.resize( size size ); //make some space Then create the VBO for this data GLuint position_vbo; glGenBuffers( 1, &position_vbo ); //gen vbo glBindBuffer( GL_ARRAY_BUFFER, position_vbo ); //bind vbo Here comes the interesting part: you need to tell the driver that you are going to use this VBO for instancing. To do this you need to tell it these things: -which vertex attribute location will you use? (2) -how many components does each piece of data have? (vec4, so 4) -what type of data are you passing? (floats) -is this data normalized? (they are positions, so probably no) -how many bytes is each piece of data? (vec4, so 4 * sizeof( float ) ) -if this data consists of more than four components (like a mat4), then where is this specific data located (relative to the whole piece of data, in bytes)? -is this data instanced? All this in code: GLuint location = 2; GLint components = 4; GLenum type = GL_FLOAT; GLboolean normalized = GL_FALSE; GLsizei datasize = sizeof( vec4 ); char* pointer = 0; //no other components GLuint divisor = 1; //instanced glEnableVertexAttribArray( location ); //tell the location glVertexAttribPointer( location, components, type, normalized, datasize, pointer ); //tell other data glVertexAttribDivisor( location, divisor ); //is it instanced? If the data you would like to pass is a mat4 for example, then you would end up using 4 vertex attribute locations to pass this data. This would require you to set up the VBO a bit differently, telling where each column (vec4) of the matrix is in each piece of data in bytes. This is required because you are passing it in GLvoid* which means that that the size of data in bytes is unknown (no pointer arithmetics). Therefore you need to work in bytes and convert that to GLvoid. In code: GLuint location = 2; GLint components = 4; GLenum type = GL_FLOAT; GLboolean normalized = GL_FALSE; GLsizei datasize = sizeof( mat4 ); char pointer = 0; GLuint divisor = 1; /** Matrix: float mat[16] = { 1, 0, 0, 0, //first column: location at 0 + 0 * sizeof( vec4 ) bytes into the matrix 0, 1, 0, 0, //second column: location at 0 + 1 * sizeof( vec4 ) bytes into the matrix 0, 0, 1, 0, //third column: location at 0 + 2 * sizeof( vec4 ) bytes into the matrix 0, 0, 0, 1 //fourth column location at 0 + 3 * sizeof( vec4 ) bytes into the matrix }; /*/ //you need to do everything for each vertex attribute location for( int c = 0; c < 4; ++c ) { glEnableVertexAttribArray( location + c ); //location of each column glVertexAttribPointer( location + c, components, type, normalized, datasize, pointer + c sizeof( vec4 ) ); //tell other data glVertexAttribDivisor( location + c, divisor ); //is it instanced? } The divisor tells the driver if the data is instanced. If the divisor is 0 (by default) it means that the data is not instanced. If it is 1 then it will be instanced. For any other value >1 the instance id (gl_InstanceID) in the vertex shader will be divided by this value. #version 330 core uniform mat4 mvp; //modelviewprojection matrix uniform mat3 normal_mat; layout(location=0) in vec4 in_vertex; //cube vertex position layout(location=1) in vec3 in_normal; //cube face normal layout(location=2) in vec4 pos; //instance data, unique to each object (instance) out vec3 normal; void main() { normal = normal_mat * in_normal; gl_Position = mvp * vec4(in_vertex.xyz + pos.xyz, 1); //write to the depth buffer } #version 330 core in vec3 normal; layout(location=0) out vec4 color; //normals go here void main() { color = vec4(normal * 0.5 + 0.5, 1); } GLuint gbuffer_instanced_shader = 0; GLint gbuffer_instanced_mvp_mat_loc = glGetUniformLocation( gbuffer_instanced_shader, "mvp" ); GLint gbuffer_instanced_normal_mat_loc = glGetUniformLocation( gbuffer_instanced_shader, "normal_mat" ); Finally all you need to do is render the cubes. Usually this would look something like this: //regular rendering glBindVertexArray( box ); for( int c = 0; c < size; ++c ) { for( int d = 0; d < size; ++d ) { glUniform4f( gbuffer_pos_loc, c * 3 - size, -2 + 0.5 * sin( radians( ( c + d + 1 )* timer.getElapsedTime().asSeconds() ) ), -d * 3, 0 ); //this gives it some ocean-like movement glDrawElements( GL_TRIANGLES, 36, GL_UNSIGNED_INT, 0 ); //two triangles per face, that is 6 * 6 = 36 vertices } } However for instancing you need to update the instance buffer, it looks like this: //instanced rendering glBindVertexArray( box ); //store positions in the buffer for( int c = 0; c < size; ++c ) { for( int d = 0; d < size; ++d ) { positions[c * size + d] = vec4( c * 3 - size, -2 + 0.5 * sin( radians( ( c + d + 1 )* timer.getElapsedTime().asSeconds() ) ), -d * 3, 0 ); } } glBindBuffer( GL_ARRAY_BUFFER, position_vbo ); //bind vbo //you need to upload sizeof( vec4 ) * number_of_cubes bytes, DYNAMIC_DRAW because it is updated per frame glBufferData( GL_ARRAY_BUFFER, sizeof( vec4 ) * positions.size(), &positions[0][0], GL_DYNAMIC_DRAW ); glDrawElementsInstanced( GL_TRIANGLES, 36, GL_UNSIGNED_INT, 0, positions.size() ); This is it. The rest of the code is setting up the deferred shader, and some controls that should be pretty straightforward. ## Interesting Points Interestingly, doing the simple sin() on the CPU to update the positions became the bottleneck after ~1.000.000 cubes. If I used a matrix, then matrix multiplication was an issue after ~160.000 cubes. This means that even when doing instancing you still need to be clever about the CPU side (doing the matrix muls using SIMD instructions, or in the shaders). After all, updating positions for lots of data is a data parallel task that the GPU usually likes. # Conclusion Instancing is very important to make sure draw calls are not a bottleneck. I hope more and more people will end up using it in the future. -project source controls: WASD, space to toggle between instancing (green) and normal rendering (red) building: use cmake to generate project (set CMAKE_BUILD_TYPE to "Release") -OpenGL history http://www.opengl.org/wiki/History_of_OpenGL -Instancing on the OpenGL wiki http://www.opengl.org/wiki/Vertex_Rendering#Instancing http://www.opengl.org/wiki/Vertex_Specification#Instanced_arrays http://www.opengl.org/wiki/Vertex_Rendering#Transform_feedback_rendering -related tutorials I found http://ogldev.atspace.co.uk/www/tutorial33/tutorial33.html http://sol.gfxile.net/instancing.html -instance culling using transform feedback # Article Update Log 20 Jun 2013: Fixed typo: vec4 --> mat4 at matrix example, usualy --> usually at 'interesting points' part, becuase --> because 15 Jun 2013: Initial release location at" should be 0 + 1 + 2 + not 0+ 0+ 0+ thanks for the constructive criticism DemonRad! However, I have to prove you wrong: what I am doing is incrementing a char* pointer byte-by-byte. What you are referring to would be incrementing a vec4* pointer by sizeof( vec4 ): vec4* a = 0; char* b = 0; a = a + 1; b = b + sizeof( vec4 ); //should be the same This would work of course if converted to GLvoid* later. Here's the project updated with an example showcasing matrix usage as Instance Data: I learned about the instancing in opengl and knew that that was really usefull. But now I also know that it increases performances ! Thanks ! That is what I was looking for. Thanks! It would be nice if the introduction provided a brief explanation of what instancing actually is before starting to explain when you should use it. Does android support any of this? I'm have this exact problem in my current android game. Only there it is even worse because each draw call is passed through the JNI. I had some trouble with my setup(GF590 with driver version 320.49). light.ps report that there is no direct cast from vec4 to vec3 and i fixed it by explicit cast it with .xyz . vec3 h = 0.5 * (l + normalize(-vs_pos).xyz); The CG compiler cry about the "layout binding" need #version 440 or #extension GL_ARB_shading_language_420pack . After changing the version it was working fine. It would be nice if the introduction provided a brief explanation of what instancing actually is before starting to explain when you should use it. I think you could expect one to at least read the corresponding wiki article: http://en.wikipedia.org/wiki/Geometry_instancing but if you'd really like to see it, I can add it. Does android support any of this? I'm have this exact problem in my current android game. Only there it is even worse because each draw call is passed through the JNI. I believe no, it does not. It should have pseudo-instancing though. Plus if I'm right OGLES 3.0 should have instancing, however the devices supporting it are just coming/came out. I had some trouble with my setup(GF590 with driver version 320.49). light.ps report that there is no direct cast from vec4 to vec3 and i fixed it by explicit cast it with .xyz . vec3 h = 0.5 * (l + normalize(-vs_pos).xyz); The CG compiler cry about the "layout binding" need #version 440 or #extension GL_ARB_shading_language_420pack . After changing the version it was working fine. well yeah I'm on AMD, and their driver allows such things I have a OGL4.x level GPU so I may not notice I'm using layout(binding=...) is not supported on OGL3.x level. I'm just used to it now. It would be nice if the introduction provided a brief explanation of what instancing actually is before starting to explain when you should use it. I think you could expect one to at least read the corresponding wiki article: http://en.wikipedia.org/wiki/Geometry_instancing but if you'd really like to see it, I can add it. It's more about how to write an article in general -- it's a good idea to define what it is that you are going to be talking about, particularly if you are 'demystifying' it. Note: Please offer only positive, constructive comments - we are looking to promote a positive atmosphere where collaboration is valued above all else. 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http://mathhelpforum.com/calculus/64234-average-cost-problem-simple-but-having-some-trouble.html	# Math Help - average cost problem - simple, but having some trouble 1. ## average cost problem - simple, but having some trouble Hello everyone! I am having some trouble working out this question: If a marginal cost function nis c'(q)=6q^2+880 dollars per unit, then the cost to increase production from 6 units to 9 units is ... I did this question in 2 ways. One of which I may have found a fault in my steps. 1) Take q=9 and q=6, sub into the marginal cost function and subtract q=9 from q=6. Personally, I don't see how that can give a reasonable answer, but it was worth a shot. 2) Integrate (although this type of question was around before I learned it) and sub in q=6 and q=9 for c(q) and subtract. So I was wondering, if that is how you should go about doing the questions or what I should do. And on the lines of that, another question was bugging me. If for all real x we assume f(g(x)) = x and f'(x) = 1+ [f(x)]^2, then g'(0) equals .. I came up with the answer of: 1 Thanks! 2. Dear finalfantasy, If for all real x we assume f(g(x)) = x and f'(x) = 1+ [f(x)]^2, then g'(0) equals .. I came up with the answer of: 1 What is the derivative of the function f(g(x)) at the point a? The chain rule says g'(a) * f'(g(a)). So $g'(0) = 1 / (1 + g^2(0))$ If we knew g(0)=0 you would be right. 3. increase in cost is $C(9) - C(6) = \int_6^9 C'(q) \, dq$ 4. Originally Posted by skeeter increase in cost is $C(9) - C(6) = \int_6^9 C'(q) \, dq$ That's what I did, but how do you know what the C is, or in other words, fixed cost? I got \$3666 by using FTC BUT that's assuming FC were 0. 5. $C'(q) = 6q^2 + 880$ antiderivative ... $C(q) = 2q^3 + 880q + k$ , where $k$ = fixed cost $C(9) - C(6) = [2(9)^3 + 880(9) + k] - [2(6)^3 + 880(6) + k]$ what happens to the fixed cost, $k$ ? doesn't matter what the fixed cost is, does it?	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 8, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9132281541824341, "perplexity": 1124.7246462004173}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-27/segments/1435375096061.71/warc/CC-MAIN-20150627031816-00178-ip-10-179-60-89.ec2.internal.warc.gz"}
https://asmedigitalcollection.asme.org/dynamicsystems/article-abstract/130/4/041010/466488/H-Fuzzy-Tracking-Control-Design-for-Nonlinear?redirectedFrom=PDF	## Abstract This paper studies the problem of $H∞$ fuzzy tracking control design for nonlinear active fault tolerant control systems based on the Takagi and Sugeno fuzzy model. Two random processes with Markovian transition characteristics are introduced to model the system component fault process and the fault detection and isolation decision process used to reconfigure the control law, respectively. The random behavior of the FDI process is conditioned on the fault process state. The parallel distributed compensation scheme is employed for the control design. As a result, a closed-loop fuzzy system with two Markovian jump parameters is obtained. Based on a stochastic Lyapunov function, a sufficient condition for stochastic stability of the closed-loop fuzzy system with a guaranteed $H∞$ model reference tracking performance is first derived. A linear matrix inequality approach to the control design is then developed to reduce the effect of the external disturbance and reference input on tracking error as small as possible. Finally, a simulation example is presented to illustrate the effectiveness of the proposed design method. 1. Veillette , R. J. , Medanic , J. V. , and Perkins , W. R. , 1992, “ Design of Reliable Control Systems ,” IEEE Trans. Autom. Control 0018-9286, 37 ( 3 ), pp. 290 304 . 2. Stoustrup , J. , and Blondel , V. D. , 2004, “ Fault Tolerant Control: A Simultaneous Stabilization Result ,” IEEE Trans. Autom. Control 0018-9286, 49 ( 2 ), pp. 305 310 . 3. Yang , G. H. , Lam , J. , and Wang , J. L. , 1998, “ Reliable H∞ Control for Affine Nonlinear Systems ,” IEEE Trans. Autom. Control 0018-9286, 43 ( 8 ), pp. 1112 1117 . 4. Wu , H.-N. , and Zhang , H.-Y. , 2005, “ Reliable Mixed L2∕H∞ Fuzzy Static Output Feedback Control for Nonlinear Systems With Sensor Faults ,” Automatica 0005-1098, 41 ( 11 ), pp. 1925 1932 . 5. Wu. , H.-N. , and Zhang , H.-Y. , 2006, “ Reliable H∞ Fuzzy Control for Continuous-Time Nonlinear Systems With Actuator Failures ,” IEEE Trans. Fuzzy Syst. 1063-6706, 14 ( 5 ), pp. 608 618 . 6. Moerder , D. D. , Halyo , N. , Broussard , J. R. , and Caglayan , A. K. , 1989, “ Application of Precomputed Control Laws in a Reconfigurable Aircraft Flight Control System ,” J. Guid. Control Dyn. 0731-5090, 12 ( 3 ), pp. 325 333 . 7. Gao , Z. , and Antsaklis , P. J. , 1991, “ Stability of the Pseudo-Inverse Method for Reconfigurable Control Systems ,” Int. J. Control 0020-7179, 53 ( 3 ), pp. 717 729 . 8. Jiang , J. , 1994, “ Design of Reconfigurable Control System Using Eigenstructure Assignment ,” Int. J. Control 0020-7179, 59 ( 2 ), pp. 395 410 . 9. Noura , H. , Sauter , D. , Hamelin , F. , and Theilliol , D. , 2000, “ Fault-Tolerant Control in Dynamic Systems: Application to a Winding Machine ,” IEEE Control Syst. Mag. 0272-1708, 20 ( 1 ), pp. 33 49 . 10. Zhang , Y. M. , and Jiang , J. , 2001, “ Integrated Active Fault-Tolerant Control Using IMM Approach ,” IEEE Trans. Aerosp. Electron. Syst. 0018-9251, 37 ( 4 ), pp. 1221 1235 . 11. Mao , Z. , and Jiang , B. , 2007, “ Fault Identification and Fault-Tolerant Control for a Class of Networked Control Systems ,” Int. J. Innov. Comp. Inf. Control , 3 ( 5 ), pp. 1121 1130 . 12. Mariton , M. , 1989, “ Detection Delays, False Alarm Rates and Reconfiguration of Control Systems ,” Int. J. Control 0020-7179, 49 ( 3 ), pp. 981 992 . 13. Srichander , R. , and Walker , B. K. , 1993, “ Stochastic Stability Analysis for Continuous-Time Fault Tolerant Control Systems ,” Int. J. Control 0020-7179, 57 ( 2 ), pp. 433 452 . 14. Shi , P. , and Boukas , E. K. , 1997, “ H∞-Control for Markovian Jumping Linear Systems With Parametric Uncertainty ,” J. Optim. Theory Appl. 0022-3239, 95 ( 1 ), pp. 75 99 . 15. Mahmoud , M. M. , Jiang , J. , and Zhang , Y. M. , 2001, “ Stochastic Stability Analysis of Fault Tolerant Control Systems in the Presence of Noise ,” IEEE Trans. Autom. Control 0018-9286, 46 ( 11 ), pp. 1810 1815 . 16. Mahmoud , M. M. , Jiang , J. , and Zhang , Y. M. , 2003, Active Fault Tolerant Control Systems: Stochastic Analysis and Synthesis , Springer-Verlag , New York . 17. Cheng , C. , Zhao , Q. , and Tao , F. , 2003, “ Stability and Performance of the Stochastic Fault Tolerant Control Systems ,” Proceedings of the 42nd IEEE Conference on Decision and Control , Maui, HI, Dec., pp. 2484 2489 . 18. Li , H. , and Zhao , Q. , 2005, “ Stabilizing Controller Parametrization of Fault Tolerant Control Systems ,” Proceedings of the 44th IEEE Conference on Decision and Control and European Control Conference, Seville , Spain , Dec., pp. 6280 6285 . 19. Tao , F. , and Zhao , Q. , 2007, “ Design of Stochastic Fault Tolerant Control for H2 Performance ,” Int. J. Robust Nonlinear Control 1049-8923, 17 ( 1 ), pp. 1 24 . 20. Willsky , A. S. , 1976, “ A Survey of Design Methods for Failure Detection in Dynamic Systems ,” Automatica 0005-1098, 12 , pp. 601 611 . 21. Patton , R. J. , Frank , P. M. , and Clark , R. N. , 1989, Fault Diagnosis in Dynamic Systems: Theory and Applications , Prentice-Hall , London, England . 22. Berdjag , D. , Christophe , C. , Cocquempot , V. , and Jiang , B. , 2006, “ Nonlinear Model Decomposition for Robust Fault Detection and Isolation Using Algebraic Tools ,” Int. J. Innov. Comp. Inf. Control , 2 ( 6 ), pp. 1337 1354 . 23. Fekih , A. , Xu , H. , and Chowdhury , F. N. , 2007, “ Neural Networks Based System Identification Techniques for Model Based Fault Detection of Nonlinear Systems ,” Int. J. Innov. Comp. Inf. Control , 3 ( 5 ), pp. 1073 1085 . 24. Mao , Z. , Jiang , B. , and Shi , P. , 2007, “ H∞ Fault Detection Filter Design for Networked Control Systems Modelled by Discrete Markovian Jump Systems ,” IET Control Theory and Applications , 1 ( 5 ), pp. 1336 1343 . 25. Takagi , T. , and Sugeno , M. , 1985, “ Fuzzy Identification of Systems and Its Applications to Modeling and Control ,” IEEE Trans. Syst. Man Cybern. 0018-9472, 15 ( 1 ), pp. 116 132 . 26. Feng , G. , 2006, “ A Survey on Analysis and Design of Model-based Fuzzy Control Systems ,” IEEE Trans. Fuzzy Syst. 1063-6706, 14 ( 5 ), pp. 676 697 . 27. Tanaka , K. , and Wang , H. O. , 2001, Fuzzy Control Systems Design and Analysis: A Linear Matrix Inequality Approach , Wiley , New York . 28. Arrifano , N. S. D. , Oliveira , V. A. , Ramos , R. A. , Bretas , N. G. , and Oliveira , R. V. , 2007, “ Fuzzy Stabilization of Power Systems in a Co-Generation Scheme Subject to Random Abrupt Variations of Operating Conditions ,” IEEE Trans. Control Syst. Technol. 1063-6536, 15 ( 2 ), pp. 384 393 . 29. Gao , H. , and Chen , T. , 2007, “ Stabilization of Nonlinear Systems Under Variable Sampling: A Fuzzy Control Approach ,” IEEE Trans. Fuzzy Syst. 1063-6706, 15 ( 5 ), pp. 972 983 . 30. Mohanlal , P. P. , and Kaimal , M. R. , 2002, “ Exact Fuzzy Modeling and Optimal Control of the Inverted Pendulum on Cart ,” Proceedings of the 41st IEEE Conference on Decision and Control , Las Vegas , NV , Dec., pp. 3255 3260 . 31. Nguang , S. K. , and Shi , P. , 2003, “ H∞ Fuzzy Output Feedback Control Design for Nonlinear Systems: An LMI Approach ,” IEEE Trans. Fuzzy Syst. 1063-6706, 11 ( 3 ), pp. 331 340 . 32. Lee , H. J. , Park , J. B. , and Chen , G. , 2001, “ Robust Fuzzy Control of Nonlinear Systems With Parametric Uncertainties ,” IEEE Trans. Fuzzy Syst. 1063-6706, 9 ( 2 ), pp. 369 379 . 33. Wu , H.-N. , and Cai , K.-Y. , 2004, “ H2 Guaranteed Cost Fuzzy Control for Uncertain Nonlinear Systems Via Linear Matrix Inequalities ,” Fuzzy Sets Syst. 0165-0114, 148 , pp. 411 429 . 34. Lo , J.-C. , and Lin , M.-L. , 2004, “ Robust H∞ Nonlinear Modeling and Control Via Uncertain Fuzzy Systems ,” Fuzzy Sets Syst. 0165-0114, 143 , pp. 189 209 . 35. Arrifano , N. S. D. , and Oliveira , V. A. , 2006, “ Robust H∞ Fuzzy Control Approach for a Class of Markovian Jump Nonlinear Systems ,” IEEE Trans. Fuzzy Syst. 1063-6706, 14 ( 6 ), pp. 738 754 . 36. Wu , H.-N. , and Cai , K.-Y. , 2006, “ Mode-Independent Robust Stabilization for Uncertain Markovian Jump Nonlinear Systems Via Fuzzy Control ,” IEEE Trans. Syst., Man, Cybern., Part B: Cybern. 1083-4419, 36 ( 3 ), pp. 509 519 . 37. Tseng , C.-S. , Chen , B.-S. , and Uang , H.-J. , 2001, “ Fuzzy Tracking Control Design for Nonlinear Dynamic Systems Via T-S Fuzzy Model ,” IEEE Trans. Fuzzy Syst. 1063-6706, 9 ( 3 ), pp. 381 392 . 38. Lian , K.-Y. , and Liou , J.-J. , 2006, “ Output Tracking Control for Fuzzy Systems Via Output Feedback Design ,” IEEE Trans. Fuzzy Syst. 1063-6706, 14 ( 5 ), pp. 628 639 . 39. Tuan , H. D. , Apkarian , P. , Narikiyo , T. , and Yamamoto , Y. , 2001, “ Parameterized Linear Matrix Inequality Techniques in Fuzzy Control System Design ,” IEEE Trans. Fuzzy Syst. 1063-6706, 9 ( 2 ), pp. 324 332 . 40. Boyd , S. , Ghaoui , L. E. , Feron , E. , and Balakrishnan , V. , 1994, Linear Matrix Inequalities in System and Control Theory , SIAM , . 41. Gahinet , P. , Nemirovski , A. , Laub , A. J. , and Chilali , M. , 1995, LMI Control Toolbox , Math Works Inc. , Natick, MA . 42. Kushner , H. J. , 1967, Stochastic Stability and Control , , New York . 43. Khalil , H. K. , 2002, Nonlinear Systems , 3rd ed., Prentice-Hall , Englewood Cliffs, NJ .	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 4, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.440855473279953, "perplexity": 21150.605073822117}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662560022.71/warc/CC-MAIN-20220523163515-20220523193515-00003.warc.gz"}
https://docs.ocean.dwavesys.com/projects/system/en/stable/	# dwave-system¶ dwave-system is a basic API for easily incorporating the D-Wave system as a sampler in the D-Wave Ocean software stack, directly or through Leap’s cloud-based hybrid solvers. It includes DWaveSampler, a dimod sampler that accepts and passes system parameters such as system identification and authentication down the stack, LeapHybridSampler, for Leap’s hybrid solvers, and other. It also includes several useful composites—layers of pre- and post-processing—that can be used with DWaveSampler to handle minor-embedding, optimize chain strength, etc. ## Documentation¶ Date Jan 24, 2021 Note This documentation is for the latest version of dwave-system. Documentation for the version currently installed by dwave-ocean-sdk is here: dwave-system. D-Wave's Ocean Software	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.16155186295509338, "perplexity": 7354.857613630402}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-17/segments/1618039398307.76/warc/CC-MAIN-20210420122023-20210420152023-00530.warc.gz"}
https://www.philipzucker.com/pytorch-trajectory-optimization-3-plugging-hessian/	I plugged in the hessian extraction code for using newton steps. When I profiled it using the oh so convenient https://github.com/rkern/line_profiler I found almost all of my time was spent in the delLy.backwards step. For each hessian I needed to run this B (the band width) times and each time cost ~0.6ms. For the entire run to converge took about 70 iterations and 1000 runs of this backwards step, which came out to 0.6 seconds. It is insane, but actually even calculating the band of the hessian costs considerably more time than inverting it. So to speed this up, I did a bizarre thing. I replicated the entire system B times. Then I can get the entire hessian band in a single call to backwards. remarkably, although B ~ 15 this only slowed backwards down by 3x. This is huge savings actually, while obviously inefficient. The entire program has gone down from 1.1s to 0.38s, roughly a 3x improvement. All in all, this puts us at 70/0.38 ~ 185 Hz for a newton step. Is that good enough? I could trim some more fat. The Fast MPC paper http://web.stanford.edu/~boyd/papers/fast_mpc.html says we need about ~5 iterations to tune up a solution, this would mean running at 40Hz. I think that might be ok. Since the hessian is hermitian it is possible to use roughly half the calls (~B/2), but then actually extracting the hessian is not so simple. I haven’t figured out a way to comfortably do such a thing yet. I think I could figure out the first column and then subtract (roughly some kind of gaussian elimination procedure). It has helped stability to regularize everything with a surprising amount of weight in the cost. I guess since I anticipate all values being in the range of -10,10, maybe this makes sense. Now I need to try not using this augmented Lagrangian method and just switching to a straight newton step. Edit: Ooh. Adding a simple backtracking line search really improves stability. import torch import matplotlib.pyplot as plt import numpy as np import torch.optim from scipy import linalg N = 100 T = 10.0 dt = T/N NVars = 4 NControls = 1 batch = (NVars+NControls)3 def getNewState(): #we 're going to also pack f into here return x, l def calc_loss(x, l , rho, prox=0): # l, #depack f, it has one less time point cost = 0.1torch.sum(x*2) #cost += prox torch.sum((x - x.detach())*2) f = x[:,1:,:NControls] #leftoverf = x[:,0,:NControls] x = x[:,:,NControls:] delx = (x[:,1:,:] - x[:, :-1,:]) / dt xbar = (x[:,1:,:] + x[:, :-1,:]) / 2 dxdt = torch.zeros(batch, N-1,NVars) THETA = 2 X = 0 V = 1 dxdt[:,:,X] = xbar[:,:,V] #print(dxdt.shape) #print(f.shape) dxdt[:,:,V] = f[:,:,0] xres = delx - dxdt lagrange_mult = torch.sum(l xres) #cost = torch.sum((x+1)2+(x+1)2, dim=0).sum(0).sum(0) #cost += torch.sum((f+1)*2, dim=0).sum(0).sum(0) #cost += 1 penalty = rhotorch.sum( xres*2) #cost += 1.0torch.sum((abs(x[:,:,THETA]-np.pi)), dim=1) #cost = 1.0torch.sum((x[:,:,:]-np.pi)2 ) cost += 1.0torch.sum((x[:,:,THETA]-np.pi)*2 torch.arange(N) / N ) cost += 0.5torch.sum(f2) #cost = 1.0torch.sum((x[:,:,:]-np.pi)*2 ) #cost = cost1 + 1.0 #cost += 0.01torch.sum(x*2, dim=1).sum(0).sum(0) #xlim = 3 #cost += 0.1torch.sum(-torch.log(xbar[:,:,X] + xlim) - torch.log(xlim - xbar[:,:,X])) #cost += 0.1torch.sum(-torch.log(xbar[:,:,V] + 1) - torch.log(1 - xbar[:,:,V]),dim=1) #cost += (leftoverf2).sum() #total_cost = cost + lagrange_mult + penalty return cost, penalty, lagrange_mult, xres def getFullHess(): #for experimentation pass #B = bandn delL = delL0[:,1:,:].view(B,-1) #remove x0 print("del ", delL[:,:10]) #y = torch.eye(B).view(B,1,B) #print(y.shape) for i in range(B): y[i,i::B]=1 #print(y[:,:2B]) print(y.shape) print(delL.shape) delLy = torch.sum(delL * y) #print(delLy) delLy.backward() #(i != B-1) #print(hess.shape) #hess[i,:] = x.grad[:,1:,:].view(-1) #also remove x0 #print(hess[i,:]) #print(hess) #print(nphess[:,:4]) #print(nphess) for i in range(B): nphess[:,i::B] = np.roll(nphess[:,i::B], -i+B//2, axis=0) print(nphess[:,:4]) #hessband = removeX0(nphess[:B//2+1,:]) return delL.detach().numpy()[0,:], nphess #hessband x, l = getNewState() rho = 0.1 prox = 0.0 for j in range(10): while True: try: cost, penalty, lagrange_mult, xres = calc_loss(x, l, rho, prox) #print(total_cost) print("hey now") #print(cost) total_cost = cost + lagrange_mult + penalty #total_cost = cost #print(hess) #print(hess.shape) #easiest thing might be to put lagrange mutlipleirs into x. #Alternatively, use second order step in penalty method. bandn = (NVars+NControls)3//2 print(hess.shape) dx = linalg.solve_banded((bandn,bandn), hess, gradL) # #print(hess) #print(hess[bandn:,:]) #df0 = dx[:NControls].reshape(-1,NControls) dx = dx.reshape(1,N-1,NVars+NControls) x[:,1:,:] -= torch.tensor(dx) print(x[:,:5,:]) #print(x[:,0,NVars:].shape) #print(df0.shape) costval = cost.detach().numpy() #break if newton_dec < 1e-10costval: break except np.linalg.LinAlgError: print("LINALGERROR") prox += 0.1 #break #print(x) l += 2 * rho * xres rho = rho * 2 #+ 0.1 #print(x) #plt.subplot(131) plt.plot(xres[0,:,0].detach().numpy(), label='Xres') plt.plot(xres[0,:,1].detach().numpy(), label='Vres') plt.plot(xres[0,:,2].detach().numpy(), label='THeres') plt.legend(loc='upper right') plt.figure() #plt.subplot(132) plt.plot(x[0,:,1].detach().numpy(), label='X') plt.plot(x[0,:,2].detach().numpy(), label='V') plt.plot(x[0,:,3].detach().numpy(), label='Theta')	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5497498512268066, "perplexity": 9897.00772926782}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-21/segments/1620243988953.13/warc/CC-MAIN-20210509002206-20210509032206-00073.warc.gz"}
https://www.hepdata.net/record/88960	Event-shape engineering for the D-meson elliptic flow in mid-central Pb-Pb collisions at $\sqrt{s_{\rm NN}} =5.02$ TeV No Journal Information The collaboration Abstract (data abstract) CERN-LHC. The production yield of prompt D mesons and their elliptic flow coefficient v_{2} were measured with the Event-Shape Engineering (ESE) technique applied to mid-central (10-30% and 30-50% centrality classes) Pb-Pb collisions at the centre-of-mass energy per nucleon pair sqrt{s_{NN}}=5.02 TeV, with the ALICE detector at the LHC. The ESE technique allows the classification of events, belonging to the same centrality, according to the azimuthal anisotropy of soft particle production in the collision. The reported measurements give the opportunity to investigate the dynamics of charm quarks in the Quark-Gluon Plasma and provide information on their participation in the collective expansion of the medium. D mesons were reconstructed via their hadronic decays at mid-rapidity, \|eta\|<0.8, in the transverse momentum interval 1<p_{T}<24 GeV/c. The v_{2} coefficient is found to be sensitive to the event-shape selection confirming a correlation between the D-meson azimuthal anisotropy and the collective expansion of the bulk matter, while the per-event D-meson yields do not show any significant modification within the current uncertainties.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9851109385490417, "perplexity": 3123.18023263253}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-35/segments/1566027315544.11/warc/CC-MAIN-20190820133527-20190820155527-00367.warc.gz"}
https://verification.asmedigitalcollection.asme.org/fluidsengineering/article-abstract/113/2/290/410785/Unsteady-Gaseous-Diffusion-Associated-With-a-Fully?redirectedFrom=fulltext	This paper gives an analysis of convective gaseous diffusion into a full cavity behind an oscillating flat-plate hydrofoil in a turbulent flow. The unsteady diffusion theory accounts for fluctuations of cavity gas pressure and length which are assumed to be harmonic oscillations but are not necessarily in phase with the hydrofoil motion. A diffusive lag function is found which, for a given reduced frequency, determines the instantaneous diffusion rate as a product of the lag function and the quasisteady mass diffusion. The present results can be used to study the rate of gas entrainment from the cavity into the wake behind the oscillating cavity. This content is only available via PDF.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8230248689651489, "perplexity": 856.4703777307907}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-14/segments/1679296949642.35/warc/CC-MAIN-20230331113819-20230331143819-00229.warc.gz"}
http://www.physicsforums.com/showthread.php?p=4165064	# Goodbye to Twinkies? by jtbell Tags: twinkies Mentor P: 11,035 This is bigger than I thought it was: [Hostess's] brands include Wonder, Nature's Pride, Dolly Madison, Drake's, Butternut, Home Pride and Merita, but it is probably best known for Twinkies - basically a cream-filled sponge cake. Many of these brands will probably re-surface under new owners after the names are sold off in the liquidation. Twinkies II, anyone? P: 71 I hope this doesn't bring down the ban-hammer down on me but: This adds weight to the whole "the world is ending December 2012" doesn't it? I mean, no more Twinkies the month before? This is a bad sign... PF Gold P: 7,368 Start checking the clearance stores, Evo. Hostess is going to liquidate unsold inventory, and maybe your orange sweets will be there. If you get extras, put them in the freezer! Mentor P: 25,716 Another case of union workers cutting off their nose to spite thier face, IMO. P: 0 Inside Edition has a recipe for Twinkies on their website. P: 424 https://petitions.whitehouse.gov/pet...ustry/cJz0ngJR There is hope. Mentor P: 25,716 Quote by nsaspook https://petitions.whitehouse.gov/pet...ustry/cJz0ngJR There is hope. LOL. Not going to happen. Emeritus Sci Advisor PF Gold P: 12,490 Darn, a company that makes all kinds of crp I can't eat is going out of business? But I'm as nostolgic as the next guy. It is hard to imagine a world without twinkies. I hear that most women prefer Ding Dongs and most men prefer Ho Hos. Is there any truth to that? Spoiler Yes, you do have to allow your mind to roam to the gutter for that one... P: 424 Quote by Ivan Seeking I hear that most women prefer Ding Dongs and most men prefer Ho Hos. Is there any truth to that? Spoiler Yes, you do have to allow your mind to roam to the gutter for that one... You owe me a keyboard. PF Gold P: 861 There are already a number of twinkie sellers on Ebay. http://www.ebay.com/sch/i.html?_trks...at=0&_from=R40 WOW Evo they even have orange cupcakes. http://www.ebay.com/sch/i.html?_trks...at=0&_from=R40 Only $19.99 for a box of eight, buy now for the holidays. http://www.ebay.com/itm/Hostess-Oran...item20cd923188 Mentor P: 11,035 Serendipitous success! I happened to go to Wal-Mart today and it occurred to me to check out their snack-cake section. Sure enough, there's a nearly empty Hostess section. I snagged one of the last two 8-cake boxes of Golden Cupcakes. Same shape and chocolate frosting as on the Cupcakes I ate as a kid, but the cake part seems to be the same as a Twinkie except for the shape (instead of chocolate). Maybe it's the same as in the orange-frosted Cupcakes. I figured$2.50 was worth it for the nostalgia. There were also several bags of small donuts (both powdered-sugar and chocolate-frosted ones) but those are pretty generic. PF Gold P: 7,368 Collateral damage in Maine. JJ Nissen runs local bakeries and distribution centers, and they are owned by Hostess' parent company. P: 2,163 I went out this morning to get one last taste of Twinkies before they all disappear, but when I got to the Woolworth's, they were shuttered. So I'm getting into my Studebaker and heading for the airport where I hope to get the next Pan Am flight to Constantinople. Wish me luck. Emeritus Sci Advisor PF Gold P: 12,490 I find myself in rare agreement with George Will and Newt Gingrich. Products like Twinkies and Ding Dongs are proven products. Hard to say what will stay and what will go but not everything is going to disappear. I would expect that most of their leader products will be produced by someone. I seriously doubt Twinkies will go away. There is probably an inside battle going on right now with various companies scrambling to produce these. I have to wonder if this was more about unions or age. I have worked in a number of factories for old companies like Hostess [automation work], Granny Goose being the worst example, and some of these places were atrocious! Most food production facilities are immaculate but there are a few horrific exceptions to the rule and I would bet ding dongs to donuts that Hostess had big problems internally. The biggest problem is often the equipment costs. Entire factories can get out of date with the cost of replacment too high to survive. Slowly the environment degenerates, failure and production losses increase, the company starts losing money, morale declines, attitudes change, no one gives a damn anymore, and eventually the company is doomed. It is a fairly familar pattern in my world. PF Gold P: 7,368 Quote by Ivan Seeking Slowly the environment degenerates, failure and production losses increase, the company starts losing money, morale declines, attitudes change, no one gives a damn anymore, and eventually the company is doomed. It is a fairly familar pattern in my world. That is true in lots of of manufacturing, Ivan. I have watched mill after mill defer capital improvements to save money. Generally, the management (well-heeled, usually) dominates the media and starts pointing fingers. It's a really sad stage of decline, and you can see the job-losses coming, along with the financial ruin of the towns. Sad, but predictable. PF Gold P: 861 Mexican Bakery Grupo Bimbo has their eye on Hostess. http://worldnews.nbcnews.com/_news/2...-twinkies?lite Mentor P: 11,035 Bimbo... Hostess... hmmm... Mentor P: 25,716 I've seen bimbo bread, they really need to rethink that name. Related Discussions General Discussion 26 Relationships 31 General Discussion 8 General Discussion 17	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.23410144448280334, "perplexity": 6744.419776380172}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-10/segments/1393999651825/warc/CC-MAIN-20140305060731-00066-ip-10-183-142-35.ec2.internal.warc.gz"}
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1160225/?tool=pubmed	• We are sorry, but NCBI web applications do not support your browser and may not function properly. More information Nucleic Acids Res. Jul 1, 2005; 33(Web Server issue): W368–W371. Published online Jun 27, 2005. PMCID: PMC1160225 # H++: a server for estimating pKas and adding missing hydrogens to macromolecules ## Abstract The structure and function of macromolecules depend critically on the ionization (protonation) states of their acidic and basic groups. A number of existing practical methods predict protonation equilibrium pK constants of macromolecules based upon their atomic resolution Protein Data Bank (PDB) structures; the calculations are often performed within the framework of the continuum electrostatics model. Unfortunately, these methodologies are complex, involve multiple steps and require considerable investment of effort. Our web server http://biophysics.cs.vt.edu/H++ provides access to a tool that automates this process, allowing both experts and novices to quickly obtain estimates of pKs as well as other related characteristics of biomolecules such as isoelectric points, titration curves and energies of protonation microstates. Protons are added to the input structure according to the calculated ionization states of its titratable groups at the user-specified pH; the output is in the PQR (PDB + charges + radii) format. In addition, corresponding coordinate and topology files are generated in the format supported by the molecular modeling package AMBER. The server is intended for a broad community of biochemists, molecular modelers, structural biologists and drug designers; it can also be used as an educational tool in biochemistry courses. ## INTRODUCTION Electrostatic interactions are often a key factor determining the properties of biomolecules (15), including their biological function such as catalytic activity (6,7), ligand binding (8), complex formation (9) and proton transport (10), as well as their structure and stability (11,12). The electrostatic properties of a molecule can change dramatically depending on the ionization (protonation) states of its titratable groups. The latter depend on the groups' type, location within the macromolecule, ionization state of other titratable sites and the pH and ionic strength of the surrounding solvent. On one hand, experimental determination, usually by NMR, of protonation equilibria is expensive and often cannot be performed for every group of interest; on the other hand, individual protons are usually not resolved by ‘standard’ X-ray crystallography, and so most of the structures from the Protein Data Bank (PDB) are incomplete, in that they are missing hydrogen atoms. Coordinates of most of the missing protons, e.g. those on CH3 groups, are relatively easy to reconstruct based on a set of straightforward chemical rules; however, predicting the protonation states of titratable groups such as Asp, Glu, Arg, Lys, Tyr, His or Cys is not trivial. A complete, all-atom structural model is usually required as input for many common molecular modeling techniques such as molecular dynamics (MD) simulations. A number of theoretical methods exist that predict pKa and protonation states of ionizable groups; see e.g. (1327). Most of these methods are based on the ‘implicit solvent’ model, in which individual water molecules and mobile solvent ions are replaced by a continuous medium with the average properties of the solvent. Some approaches go beyond this and explicitly take into account the solvent's degrees of freedom (19,21,27), albeit at a significantly larger computational expense. Since electrostatic interactions are the key factor determining the protonation equilibria, considerable effort has been spent to improve the accuracy of their estimation. Apart from the very early approaches (13,28) that represented a molecule as a low dielectric sphere and that made mostly qualitative predictions, all modern methods use atom-detail information from high-resolution PDB structures. Generally, higher resolution data yield more accurate predictions. Although these methods vary in the details of the underlying physical models, they share one common feature—computational and algorithmic complexity. The latter stems, in general, from the sensitivity of the computed electrostatic interactions to the approximations involved and the details of the input structure. Hence, the computational process usually involves multiple non-trivial steps. There is often an additional complication arising from irregularities within the input PDB structures, such as naming inconsistencies and missing or duplicate atom records. Significant ‘pre-processing’ of structures is therefore required. As a result, modern methods that predict protonation equilibria and add missing hydrogens to PDB structures are frequently associated with a rather steep learning curve, often precluding novices from using them. Even for experts, the manual set-up of such calculations is often time consuming, and potentially useful variations of the input parameters and/or structural models remain unexplored. This paper describes the freely available web server http://biophysics.cs.vt.edu/H++, which is designed to automate prediction of pKa and protonation states of ionizable residues in macromolecules, using atomic resolution structures as input. The output structure contains missing hydrogens added according to calculated protonation states and is available in several formats used by a number of popular molecular modeling packages. The calculations are based on the standard continuum solvent methodology (15), within the frameworks of either the generalized Born (GB) or the Poisson–Boltzmann (PB) models (user-specified). All steps of the computational process are fully automated. Commonly used input parameters are accessible via a simple interface that provides reasonable defaults. The server is intended for both experts and non-experts. ## MATERIALS AND METHODS ### Pre-processing of submitted structures Structures are pre-processed differently depending upon their input format (see the flowchart in Figure 1). Two input formats are supported by the H++ website, PDB and PQR. These files differ in that PQR files already have charges and radii assigned to each atom whereas PDB files do not. Flowchart of computations performed by the H++ server described here. The input is a structure file in either PDB or PQR (PDB + charges + radii) format. The output includes computed pK1/2 values for all titratable groups, as well as titration curves, ... If the input file is in PQR format, H++ makes minimal changes because it is assumed that the format is already suitable for electrostatic calculations. Changes made are as follows: atom names of all titratable amino acids are brought into accordance with the format adopted by the AMBER (29) package and consistency checks are performed. These checks ensure that the total charge of the system is an integer (within a ±0.05 unit charge tolerance per amino acid) and the atomic radii are between 0.5 and 3 Å. If any of the above checks fail, the sequence of residues is discontinuous or the atom names are different from the PDB standard and cannot be recognized, execution terminates. For a structure submitted in the conventional PDB format, H++ deletes all HETATM records; that is, only those atoms that belong to amino acids or nucleotides are kept. This is the ‘clean-up’ step in Figure 1. Removal of explicit water molecules and mobile counterions is generally consistent with the implicit solvent framework in which solvation effects are accounted for in the mean-field manner. If necessary, removed ligands can be included in the calculations by submitting the complete structure in the PQR format, avoiding the ‘clean-up’ step. Sequence continuity is verified and all atom names are brought into accordance with the format adopted by the AMBER package. Deuterium atoms are replaced with equivalent hydrogens. ### Addition of missing atoms and optimization of hydrogens This section applies only to input structures in PDB format. Missing heavy atoms and protons (assuming standard protonation states of titratable groups) are added, and atomic partial charges and radii (Bondi) are assigned using the PROTONATE and LEAP modules of AMBER. This is followed by an MD-based optimization of the positions of the added hydrogens. The protocol was tested earlier (10) in a similar context; it consists of three consecutive stages during which only hydrogens are allowed to move: first, 100 steps of conjugate gradient minimization; second, 500 steps of MD at 300 K, with all torsional potentials involving hydrogens set to zero; and third, 100 steps of conjugate gradient minimization with the torsional potential returned to normal values. The AMBER parm99 force-field is used, where the integration time-step is 1 fs and the charge–charge interactions are computed in a uniform ‘vacuum’ of dielectric out = 4. ### Electrostatic calculations The continuum electrostatics methodology widely used to calculate the energetics of proton transfer is described elsewhere (15,30); the model is available in the free software package MEAD (31). The H++ calculations rely upon the single-conformer version of MEAD; conformational variability is partially accounted for by the ‘smeared charge’ representation of titratable groups (see below) and the simulated annealing of protons described above. Although it is not the most systematic or exhaustive way of incorporating conformational variability, we believe, based on previous experiences (10,22,30), that this particular model is a reasonable balance between speed and accuracy, and is therefore a good choice for web-based calculations. In this model, the molecule is treated as a low dielectric medium in, and the surrounding solvent is assigned a high dielectric constant out. The electrostatic screening effects of (monovalent) salt enter via the Debye–Huckel screening parameter $κ[Å−1]≈0.316[salt][mol/l]$. The salt concentration, in and out are accessible to the user, and reasonable defaults are provided. The difference between the pKa of a sidechain and the pKa of the corresponding model compound in free solution is determined by the combined effect of two distinct contributions to the total electrostatic (free) energy change. The first is the ‘Born term’ or desolvation penalty, which always penalizes burial of a charge inside a low dielectric medium. The second is the background term, which represents the electrostatic interactions of the group in question with all other fixed charges in the molecule not belonging to any titratable groups. These energy terms, as well as the matrix of site–site interactions, are estimated through a sequence of calculations in which sites in the protein and their corresponding model compounds have their charge distributions set to those of the protonated or deprotonated form, and suitable energy differences are taken. For the protonated states of Asp and Glu, in which the correct location of the proton is not known a priori, a ‘smeared charge’ representation is employed, in which the neutralizing positive charge is symmetrically distributed: 0.45 on each carbonyl oxygen atom, and 0.1 on the carbon atom. The electrostatic calculations are based either on a GB or a PB model, as requested by the user. The particular GB model we are using was found earlier (32) to work reasonably well in pK calculations on proteins; here its improved version (33) is used. The set-up and finite-difference solution of the PB problems or analytical GB calculations are carried out using the MEAD program package. In the finite-difference lattices, two levels of focusing are used. In the coarsest level the bounding box is set to twice the molecule's maximum extent and the grid points are spaced 2 Å apart. The finest lattice is focused on the region of interest, and the grid points are 0.5 Å apart. The probe radius for defining the molecular surface, which is used as the boundary between the interior and exterior dielectric regions, is set to 1.4 Å. ### Calculating titration curves, pK1/2 and protonation states The electrostatic calculations outlined above provide (free) energies of each of the 2N protonation microstates (10) in the system, where N is the number of ionizable sites. To make the subsequent calculation of the partition functions (and pK1/2) manageable, a fast variant of a clustering approach is used (34). The approach subdivides the interacting sites into independent clusters based upon the strength of electrostatic site–site interactions between them. All electrostatic interactions for each ionizable site are sorted from highest to lowest; the top Cmax sites are then selected to contribute to the calculation, and all others are ignored. The partition function for the site is then factored into computationally manageable components of maximum size Cmax. Here, Cmax = 17 is used: in tests on 600 representative proteins (35), we found (J. Myers, G. Grothaus and A. Onufriev, manuscript submitted) that Cmax = 17 resulted in average errors of 0.2 pK units, compared with a standard treatment based upon a Monte Carlo approach (16). The probability of protonation is computed for every site over a range of pH values equally spaced by 0.1 pH units apart. Individual curves can be displayed for user-selected residues, and the total protonation curve is generated, showing the computed isoelectric point of the molecule. A diagram showing the 10 lowest protonation states and their relative free energies is also generated. These diagrams were found useful (10) for analysis of proton transfer events in biomolecular systems. ### Generating the PDB structure in its predicted protonation state The computed titration curves provide an estimate of the probability of protonation of each titratable site at the (user-specified) pH of the solvent. A simple scheme is used for assignment of protonation states: if the estimated probability is <0.5, the site is considered deprotonated; otherwise, the site is protonated. We follow AMBER conventions in placement of new hydrogen atoms and selection of hydrogen atoms to be removed. Deprotonated (neutral) states of Arg and Tyr, not available in the AMBER databases, are obtained from the protonated forms by removal of the HH22 and HH protons, respectively; their partial charges are brought into accordance with the appropriate model compound values supplied by the MEAD package. The structures submitted in PQR format do not undergo re-assignment of protonation states, allowing greater flexibility for this input format. ## CONCLUSION The H++ web server described here automates the process of calculating pKa, protonation states and titration curves of ionizable groups in macromolecules, given an atomic resolution structure as input. In addition, the server generates the properly protonated structures for use in other popular molecular modeling applications, such as MD. The calculations are based on the established continuum electrostatics methodology, which has been successfully used for this purpose over more than a decade. We expect H++ to become a useful tool for the broad biochemical, structural and computational biology community, as well as drug designers. It can also be a useful educational resource. ## Acknowledgments We thank Grigori Sigalov and Jory Zmuda for useful comments and suggestions. We are also grateful to Yuri Pevzner for the help with testing and to Derek Rountree for the help with incorporating the latest GB model into the MEAD package. Funding to pay the Open Access publication charges for this article was provided by Virginia Tech. Conflict of interest statement. None declared. ## REFERENCES 1. Perutz M. Electrostatic effects in proteins. Science. 1978;201:1187–1191. [PubMed] 2. 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[PubMed] Articles from Nucleic Acids Research are provided here courtesy of Oxford University Press ## Formats: ### Related citations in PubMed See reviews...See all... ### Cited by other articles in PMC See all... • Compound Compound • PubMed PubMed PubMed citations for these articles • Substance Substance	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 1, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5014330148696899, "perplexity": 5989.764545832169}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-15/segments/1397609539665.16/warc/CC-MAIN-20140416005219-00185-ip-10-147-4-33.ec2.internal.warc.gz"}
http://www.cper.org/mod/glossary/showentry.php?eid=44	# Feedback ## Definitions 1. Communication / education: (critical) assessment on information produced (verbal of lexical). 2. Cybernetics: the signal that is looped back to control a system within itself. 3. Music / electronics: the high-pitched howling noise heard when there's a loop between a microphone and a speaker. ## Explanation ### Cause-and-effect Feedback occurs when outputs of a system are "fed back" as inputs as part of a chain of cause-and-effect that forms a circuit or loop. The system can then be said to "feed back" into itself. The notion of 'cause-and-effect' has to be handled carefully when applied to feedback systems: Simple causal reasoning about a feedback system is difficult because the first system influences the second and second system influences the first, leading to a circular argument. This makes reasoning based upon cause and effect tricky, and it is necessary to analyze the system as a whole. In this context, the term "feedback" has also been used as an abbreviation for: • Feedback signal: the conveyance of information fed back from an output, or measurement, to an input, or effector, that affects the system. • Feedback loop: the closed path made up of the system itself and the path that transmits the feedback about the system from its origin (for example, a sensor) to its destination (for example, an actuator). Figure: Simple feedback loop showing circular cause-effect relationship. ### Positive - Negative The terms positive and negative feedback are defined in different ways within different disciplines: 1. The altering of the gap between reference and actual values of a parameter, based on whether the gap is widening (positive) or narrowing (negative) [in physics, cybernetics, biology]. 2. The valence of the action or effect that alters the gap, based on whether it has a happy (positive) or unhappy (negative) emotional connotation to the recipient or observer [in didactics, comunication training]. ## Fields of Application ### Biology In biological systems such as organisms, ecosystems, or the biosphere, most parameters must stay under control within a narrow range around a certain optimal level under certain environmental conditions. The deviation of the optimal value of the controlled parameter can result from the changes in internal and external environments. A change of some of the environmental conditions may also require change of that range to change for the system to function. The value of the parameter to maintain is recorded by a reception system and conveyed to a regulation module via an information channel. An example of this is Insulin oscillations. Biological systems contain many types of regulatory circuits, both positive and negative. As in other contexts, positive and negative do not imply that the feedback causes good or bad effects. A negative feedback loop is one that tends to slow down a process, whereas the positive feedback loop tends to accelerate it. Feedback is also central to the operations of genes and gene regulatory networks. Repressor (see Lac repressor) and activator proteins are used to create genetic operons, which were identified by Francois Jacob and Jacques Monod in 1961 as feedback loops. These feedback loops may be positive (as in the case of the coupling between a sugar molecule and the proteins that import sugar into a bacterial cell), or negative (as is often the case in metabolic consumption). On a larger scale, feedback can have a stabilizing effect on animal populations even when profoundly affected by external changes, although time lags in feedback response can give rise to predator-prey cycles. In zymology, feedback serves as regulation of activity of an enzyme by its direct product(s) or downstream metabolite(s) in the metabolic pathway. The hypothalamic–pituitary–adrenal axis is largely controlled by positive and negative feedback. ### Psychology In psychology, the body receives a stimulus from the environment or internally that causes the release of hormones. Release of hormones then may cause more of those hormones to be released, causing a positive feedback loop. This cycle is also found in certain behaviour. For example, "shame loops" occur in people who blush easily. When they realize that they are blushing, they become even more embarrassed, which leads to further blushing, and so on.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.48429590463638306, "perplexity": 1465.2953631545909}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-13/segments/1552912204077.10/warc/CC-MAIN-20190325153323-20190325175323-00426.warc.gz"}
http://nrich.maths.org/5061/solution	### Chocolate There are three tables in a room with blocks of chocolate on each. Where would be the best place for each child in the class to sit if they came in one at a time? ### Doughnut How can you cut a doughnut into 8 equal pieces with only three cuts of a knife? ### Rectangle Tangle The large rectangle is divided into a series of smaller quadrilaterals and triangles. Can you untangle what fractional part is represented by each of the ten numbered shapes? # Fraction Fascination ##### Stage: 2 Challenge Level: We had several good solutions to this problem. They came from Cong who goes to St Peter's RC Primary, Aberdeen; Terence from Brumby Engineering College and Ben at Kingsbarns Primary. Cong coloured the first image: He said: The green and dark blue shape is $\frac{1}{4}$ of the square's area (each). The blue shape is $\frac{1}{8}$ of the square's area. From these three shapes you can work out the red shape's area which is $\frac{3}{8}$. Cong then sent in a new version of the large design: He goes on to say: This shape is made from combining 4 small squares together to get this big shape. The shape in the middle of the large square is a rhombus. The big blue shape is $\frac{1}{4}$ of the large square's area because it is $\frac{1}{4}$ of the small square and because the large square is four times as big as the small square, which means that it will be the same fraction.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5007364749908447, "perplexity": 1061.8300917707277}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-35/segments/1409535921550.2/warc/CC-MAIN-20140901014521-00087-ip-10-180-136-8.ec2.internal.warc.gz"}
https://stats.stackexchange.com/questions/386025/why-is-correlation-formula-the-way-it-is-or-say-how-it-formed?noredirect=1	Why is correlation formula the way it is? Or Say how it formed? [duplicate] I am really being confused by why the correlation formula is called the correlation of two variables $$X$$ and $$Y$$. Also how is it derived? The part where we divide covariance by product of standard derivation of $$X$$ and standard derivation of $$Y$$ is the most confusing for me. Please explain the reasons or provide some good source for such things. marked as duplicate by Stefan, user158565, kjetil b halvorsen, Michael Chernick, Juho KokkalaJan 8 at 7:07 • One way of thinking about the correlation and it's specific representation is that it is a unitless quantity. So by dividing the product moment estimator $E(XY)$ by the SD of X and Y, you get something that doesn't depend on the scale of either variable (in a sense). – AdamO Jan 7 at 17:22 • Correlation equals covariance of standardized variables. – Michael M Jan 7 at 17:23 • Have a look here maybe that helps: stats.stackexchange.com/questions/256344/… Or here: stats.stackexchange.com/questions/70969/… – Stefan Jan 7 at 17:24 Maybe going back to the notion of covariance would help. Say we have two random variables $$X$$ and $$Y$$, with a certain number $$n$$ of independent realizations $$x_1,x_2,\dots x_n$$ and $$y_1,y_2,\dots y_n$$. We know that the formula for the sample covariance is $$\sigma_{xy} =\frac{1}{n-1}\sum_{i=1}^n(x_i-\bar{x})(y_i-\bar{y})$$ where $$\bar{x}$$ and $$\bar{y}$$ are respectively sample means for $$X$$ and $$Y$$. Now, thanks to the Cauchy-Schwarz inequality, we have that the sample covariance is bounded by the product of the standard deviations of the two random variables, which I will denote with $$\sigma_x$$ and $$\sigma_y$$. We have then that $$-\sigma_x\sigma_y \leq \sigma_{xy}\leq \sigma_x\sigma_y$$ Now divide all terms in the inequality by $$\sigma_x\sigma_y$$ and you have the formula for correlation $$-\frac{\sigma_x\sigma_y}{\sigma_x\sigma_y} \leq \frac{\sigma_{xy}}{\sigma_x\sigma_y}\leq \frac{\sigma_x\sigma_y}{\sigma_x\sigma_y}$$ $$-1 \leq \frac{\sigma_{xy}}{\sigma_x\sigma_y} \leq 1$$ with the correct bounds, $$-1$$ and $$1$$. If you grasp the notion of covariance, then you'll surely see that it is simply a standardized version of the latter. • standardized version means? – Vicrobot Jan 7 at 18:02 • It means that it gives you the same information as the covariance, but on a scale that varies from $-1$ to $1$. As others have put it, it is indeed unitless, while covariance is expressed in the units in which the variables were measured. – Easymode44 Jan 7 at 18:06 • So how does that division ensures that resultant amount (i.e. corr.) will still increase in magnitude as there will be a more linear relationship? – Vicrobot Jan 7 at 19:46 • This behavior is already an inherent quality of covariance. CS ensures the inequality, division only gives a measure of linear relationship that is not dependent on units of measure (which can be a problem, especially when dealing with big magnitudes) – Easymode44 Jan 7 at 20:01 • One last thing; what makes it pretty sure that when the relationship tends to linearity; the cov. tends to be equal to magnitude(σ X σ Y) ?? – Vicrobot Jan 7 at 20:35	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 22, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8243358731269836, "perplexity": 404.8406883784032}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-26/segments/1560627997801.20/warc/CC-MAIN-20190616062650-20190616084650-00484.warc.gz"}
http://mathhelpforum.com/advanced-applied-math/280809-does-limit-approximate-zero-set-converge-zero-set.html	# Thread: Does limit of "approximate zero set" converge to the zero set? 1. ## Does limit of "approximate zero set" converge to the zero set? Let $\displaystyle f:\mathbb{R}^m\rightarrow\mathbb{R}^m$. Define the zero set by $\displaystyle \mathcal{Z}\triangleq\{x\in\mathbb{R}^m \| f(x)=\mathbf{0}\}$ and an $\displaystyle \epsilon$-approximation of this set by $\displaystyle \mathcal{Z}_\epsilon\triangleq\{x\in\mathbb{R}^m\|~ \|\|f(x)\|\|\leq\epsilon\}$ for some $\displaystyle \epsilon>0$. Clearly $\displaystyle \mathcal{Z}\subseteq \mathcal{Z}_\epsilon$. Can one assume any condition on the function $\displaystyle f$ so that $\displaystyle \lim_{\epsilon\rightarrow 0}~\max_{x\in \mathcal{Z}_\epsilon}~\text{dist}(x, \mathcal{Z})=0,$ holds? I know in general this doesn't hold by this example (function of a scalar variable): \displaystyle f(x)=\left\{\begin{align} 0,\quad{x\leq 0}; \\ 1/x,\quad x>0. \end{align} \right. I really appreciate any help or hint. Thank you. 2. ## Re: Does limit of "approximate zero set" converge to the zero set? If $f$ is a continuous bijection, this follows trivially. You can probably relax the condition to monotone and continuous and still arrive at the conclusion. 3. ## Re: Does limit of "approximate zero set" converge to the zero set? Actually $\displaystyle f$ here is the gradient of a non-convex function $\displaystyle g$, i.e. $\displaystyle f=\nabla g$ which is not monotone, and the zero set is the set of critical points. However, I assume $\displaystyle g$ is $\displaystyle \mathcal{C}^\infty$. If $f$ is a continuous bijection, this follows trivially. You can probably relax the condition to monotone and continuous and still arrive at the conclusion. Actually $\displaystyle f$ here is the gradient of a non-convex function $\displaystyle g$, i.e. $\displaystyle f=\nabla g$ which is not monotone, and the zero set is the set of critical points. However, I assume $\displaystyle g$ is $\displaystyle \mathcal{C}^\infty$.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9977381825447083, "perplexity": 497.6668689165444}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-26/segments/1529267860089.13/warc/CC-MAIN-20180618070542-20180618090542-00596.warc.gz"}
http://science.sciencemag.org/content/early/2012/08/29/science.1228380	Report # Kepler-47: A Transiting Circumbinary Multiplanet System See allHide authors and affiliations Science 28 Aug 2012: 1228380 DOI: 10.1126/science.1228380 ## Abstract We report the detection of Kepler-47, a system consisting of two planets orbiting around an eclipsing pair of stars. The inner and outer planets have radii 3.0 and 4.6 times that of Earth, respectively. The binary star consists of a Sun-like star and a companion roughly one-third its size, orbiting each other every 7.45 days. With an orbital period of 49.5 days, 18 transits of the inner planet have been observed, allowing a detailed characterization of its orbit and those of the stars. The outer planet's orbital period is 303.2 days, and although the planet is not Earth-like, it resides within the classical “habitable zone,” where liquid water could exist on an Earth-like planet. With its two known planets, Kepler-47 establishes that close binary stars can host complete planetary systems. View Full Text	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8763572573661804, "perplexity": 2718.715404371463}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-22/segments/1526794864466.23/warc/CC-MAIN-20180521181133-20180521201133-00538.warc.gz"}
https://datascience.stackexchange.com/questions/24794/python-pandas-interpolation-with-fixed-value	# Python Pandas - Interpolation with fixed value Say we have a pandas series with the following values [np.nan, np.nan, 1, np.nan, 2, np.nan] What is the most efficient way fill the nan value with 0 in the middle. so we have [np.nan, np.nan, 1, 0, 2, np.nan] In other word, how to we do interpolation with a fixed value, or a .fillna operation but ignore the nan at the beginning and end of the array. Current solution, I am using def interpolate_with_fixed(s, value=0): i = s.first_valid_index() j = s.last_valid_index() s.loc[i:j].fillna(value, inplace=True) return s • This my hackish solution. Would like to know if there is a more elegent solution. Nov 16 '17 at 5:06 I think your solution is quite idiomatic. Here is an alternative solution: In [355]: s.loc[s.notnull().idxmax() : s[::-1].notnull().idxmax()].fillna(0, inplace=True) In [356]: s Out[356]: 0 NaN 1 NaN 2 1.0 3 0.0 4 2.0 5 NaN dtype: float64	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.48376375436782837, "perplexity": 5360.18598843979}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-49/segments/1637964358180.42/warc/CC-MAIN-20211127103444-20211127133444-00051.warc.gz"}
https://embdev.net/topic/129071	# Forum: ARM programming with GCC/GNU tools C++ Linker Problem Rate this post 0 ▲ useful ▼ not useful Hello, I use NutOS (see http://www.ethernut.de) and using C++. They provide Script is the following. To be honest, I have no idea of linker scripts, this one is used: http://cvs.sourceforge.net/viewcvs.py/ethernut/nut/arch/arm/ldscripts/at91_ram.ld?rev=1.1&view=markup I get the following error message: winarm\bin\..\lib\gcc\arm-elf\4.0.2\..\..\..\..\arm-elf\bin\ld.exe: error: no memory region specified for loadable section erIhEC2Ev' Any hints are welcome. Matthias Rate this post 0 ▲ useful ▼ not useful Matthias Wilde wrote: > I use NutOS (see http://www.ethernut.de) and using C++. They provide > Script is the following. To be honest, I have no idea of linker scripts, > this one is used: > > http://cvs.sourceforge.net/viewcvs.py/ethernut/nut/arch/arm/ldscripts/at91_ram.ld?rev=1.1&view=markup > > > I get the following error message: > > winarm\bin\..\lib\gcc\arm-elf\4.0.2\..\..\..\..\arm-elf\bin\ld.exe: > error: no > memory region specified for loadable section > .gnu.linkonce.t._ZN15TemplateCoun > erIhEC2Ev' The linker-script from the ethernet-cvs seems to be a "c-only" script. I linkonce-entries and ctor/dtor-sections and data) but currently no time to create a modified version. Maybe later today or tomorrow. The startup-code has to be modified too to call the ctors before "branch to main()". Martin Thomas Rate this post 0 ▲ useful ▼ not useful Hi Martin, yes, you are right, it is running for C. However I tried to expand the script for C++, but as I said I have no idea how. However, if you could insert the missing parts that would be great. Or if you could just give me some hintswhere I can get information or an example how a C++ linker script should look like - that would be also very helpful. Thank you very much Matthias Martin Thomas wrote: > The linker-script from the ethernet-cvs seems to be a "c-only" script. I > have some ideas about what has to be added/changed (i.e. the > linkonce-entries and ctor/dtor-sections and data) but currently no time > to create a modified version. Maybe later today or tomorrow. The > startup-code has to be modified too to call the ctors before "branch to > main()". > > Martin Thomas Rate this post 0 ▲ useful ▼ not useful Hello again, I think I can solve it, I just looked for the linker default script. I try tonight and let you know. Matthias Rate this post 0 ▲ useful ▼ not useful Ok, after two nights, I could not solve the problem. Now I get unresoved functions of NutOS. To be honest, linker scripts are more complicated than I expected..... I have to wait for an expert .... Best regards Matthias Rate this post 0 ▲ useful ▼ not useful Matthias Wilde wrote: I have modified the ethernut/NutOS-Linker-Script. Completly untested but should give an idea. The script will be available for some days on: http://www.siwawi.arubi.uni-kl.de/avr_projects/arm_projects/winarmtests/ > Now I get unresoved functions of NutOS. Maybe a "C/C++" symbol-name problem here. As far as I know the NutOS header-files do not include an extern "C"-Wrapper like #ifdef __cplusplus extern "C" { #endif [...] #ifdef __cplusplus } #endif At least I do not see them in the few headers files which I have read in the CVS. Without this "wrappter" there will be unresolved externals when the NutOS-libraries are compiled with the C-compiler and the user program is compiled with the C++-compiler. For a test you could try extern "C" { #include "a_NutOS_include_file.h" #include "another_NutOS_include_file.h" } Hope this helps Martin Thomas Rate this post 0 ▲ useful ▼ not useful Hello Martin, thnak you very much for the linker script. I will test it end of this week. The extern "C" problem I know and I allready included the header files like you recommended. However, might be an other issue. I try your linker script and let you know the results. Best regards Matthias Rate this post 0 ▲ useful ▼ not useful Hello Martin, Ok I promised a several weeks ago "I will test it end of the week"..... I tested it now and your suggestion works for me perfect. THANK YOU VERY MUCH!! restrictions / copyright issues within Nut/OS? Best regards Matthias Rate this post 0 ▲ useful ▼ not useful Matthias Wilde wrote: > Hello Martin, > > Ok I promised a several weeks ago "I will test it end of the week"..... > > I tested it now and your suggestion works for me perfect. > > THANK YOU VERY MUCH!! > > One last question. Can we use your additional changes without any > restrictions / copyright issues within Nut/OS? I have got my information from the sources given in the modified linker-script and a little "try and error" with my gcc-C++-test on the LPC2000. I don't think that there are any restrictions or copyright-issues since "it's just the way it has to be done". It would be nice if you or Harald could keep my name somewhere in the header of the file. Martin Thomas • $formula (LaTeX syntax)$	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.15870165824890137, "perplexity": 7406.49242324621}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-40/segments/1600400227524.63/warc/CC-MAIN-20200925150904-20200925180904-00327.warc.gz"}
https://planetmath.org/restricteddirectproduct	# restricted direct product Let $\{G_{v}\}_{v\in V}$ be a collection of locally compact topological groups. For all but finitely many $v\in V$, let $H_{v}\subset G_{v}$ be a compact open subgroup of $G_{v}$. The of the collection $\{G_{v}\}$ with respect to the collection $\{H_{v}\}$ is the subgroup $G:=\left\{\left.(g_{v})_{v\in V}\in\prod_{v\in V}G_{v}\ \right\|\ g_{v}\in H_{v% }\text{ for all but finitely many v\in V}\right\}$ of the direct product $\prod_{v\in V}G_{v}$. We define a topology on $G$ as follows. For every finite subset $S\subset V$ that contains all the elements $v$ for which $H_{v}$ is undefined, form the topological group $G_{S}:=\prod_{v\in S}G_{v}\times\prod_{v\notin S}H_{v}$ consisting of the direct product of the $G_{v}$’s, for $v\in S$, and the $H_{v}$’s, for $v\notin S$. The topological group $G_{S}$ is a subset of $G$ for each such $S$, and we take for a topology on $G$ the weakest topology such that the $G_{S}$ are open subsets of $G$, with the subspace topology on each $G_{S}$ equal to the topology that $G_{S}$ already has in its own right. Title restricted direct product RestrictedDirectProduct 2013-03-22 12:35:38 2013-03-22 12:35:38 djao (24) djao (24) 5 djao (24) Definition msc 11R56 msc 22D05	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 25, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9627964496612549, "perplexity": 152.5959966618685}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178369553.75/warc/CC-MAIN-20210304235759-20210305025759-00322.warc.gz"}
http://exxamm.com/QuestionSolution13/Aptitude/A+train+moving+with+uniform+speed+crosses+a+pole+in+2+s+and+a+250+m+long+bridge+in+7+s+F+nd+the+length+of+the/1473056846	A train moving with uniform speed · crosses a pole in 2 s and a 250 m long bridge in 7 s. F'nd the length of the ### Question Asked by a Student from EXXAMM.com Team Q 1473056846. A train moving with uniform speed · crosses a pole in 2 s and a 250 m long bridge in 7 s. F'nd the length of the train. [SSC CGL 2010] A 150 m B 120 m C 100 m D 80 m #### HINT (Provided By a Student and Checked/Corrected by EXXAMM.com Team) #### Access free resources including • 100% free video lectures with detailed notes and examples • Previous Year Papers • Mock Tests • Practices question categorized in topics and 4 levels with detailed solutions • Syllabus & Pattern Analysis	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.31943026185035706, "perplexity": 7706.3063550305005}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-47/segments/1542039743007.0/warc/CC-MAIN-20181116091028-20181116113028-00399.warc.gz"}
https://betterexplained.com/articles/intuitive-trigonometry/	Trig mnemonics like SOH-CAH-TOA focus on computations, not concepts: TOA explains the tangent about as well as x2 + y2 = r2 describes a circle. Sure, if you’re a math robot, an equation is enough. The rest of us, with organic brains half-dedicated to vision processing, seem to enjoy imagery. And “TOA” evokes the stunning beauty of an abstract ratio. I think you deserve better, and here’s what made trig click for me. • Visualize a dome, a wall, and a ceiling • Trig functions are percentages to the three shapes ## Motivation: Trig Is Anatomy Imagine Bob The Alien visits Earth to study our species. Without new words, humans are hard to describe: “There’s a sphere at the top, which gets scratched occasionally” or “Two elongated cylinders appear to provide locomotion”. After creating specific terms for anatomy, Bob might jot down typical body proportions: • The armspan (fingertip to fingertip) is approximately the height • A head is 5 eye-widths wide Well, when Bob finds a jacket, he can pick it up, stretch out the arms, and estimate the owner’s height. And head size. And eye width. One fact is linked to a variety of conclusions. Even better, human biology explains human thinking. Tables have legs, organizations have heads, crime bosses have muscle. Our biology offers ready-made analogies that appear in man-made creations. Now the plot twist: you are Bob the alien, studying creatures in math-land! Generic words like “triangle” aren’t overly useful. But labeling sine, cosine, and hypotenuse helps us notice deeper connections. And scholars might study haversine, exsecant and gamsin, like biologists who find a link between your fibia and clavicle. And because triangles show up in circles… …and circles appear in cycles, our triangle terminology helps describe repeating patterns! Trig is the anatomy book for “math-made” objects. If we can find a metaphorical triangle, we’ll get an armada of conclusions for free. ## Sine/Cosine: The Dome Instead of staring at triangles by themselves, like a caveman frozen in ice, imagine them in a scenario, hunting that mammoth. Pretend you’re in the middle of your dome, about to hang up a movie screen. You point to some angle “x”, and that’s where the screen will hang. The angle you point at determines: • sine(x) = sin(x) = height of the screen, hanging like a sign • cosine(x) = cos(x) = distance to the screen along the ground [“cos” ~ how “close”] • the hypotenuse, the distance to the top of the screen, is always the same Want the biggest screen possible? Point straight up. It’s at the center, on top of your head, but it’s big dagnabbit. Want the screen the furthest away? Sure. Point straight across, 0 degrees. The screen has “0 height” at this position, and it’s far away, like you asked. The height and distance move in opposite directions: bring the screen closer, and it gets taller. ## Tip: Trig Values Are Percentages Nobody ever told me in my years of schooling: sine and cosine are percentages. They vary from +100% to 0 to -100%, or max positive to nothing to max negative. Let’s say I paid \$14 in tax. You have no idea if that’s expensive. But if I say I paid 95% in tax, you know I’m getting ripped off. An absolute height isn’t helpful, but if your sine value is .95, I know you’re almost at the top of your dome. Pretty soon you’ll hit the max, then start coming down again. How do we compute the percentage? Simple: divide the current value by the maximum possible (the radius of the dome, aka the hypotenuse). That’s why we’re told “Sine = Opposite / Hypotenuse”. It’s to get a percentage! A better wording is “Sine is your height, as a percentage of the hypotenuse”. (Sine becomes negative if your angle points “underground”. Cosine becomes negative when your angle points backwards.) Let’s simplify the calculation by assuming we’re on the unit circle (radius 1). Now we can skip the division by 1 and just say sine = height. Every circle is really the unit circle, scaled up or down to a different size. So work out the connections on the unit circle and apply the results to your particular scenario. Try it out: plug in an angle and see what percent of the height and width it reaches: The growth pattern of sine isn’t an even line. The first 45 degrees cover 70% of the height, and the final 10 degrees (from 80 to 90) only cover 2%. This should make sense: at 0 degrees, you’re moving nearly vertical, but as you get to the top of the dome, your height changes level off. ## Tangent/Secant: The Wall But can we make the best of a bad situation? Sure. What if we hang our movie screen on the wall? You point at an angle (x) and figure out: • tangent(x) = tan(x) = height of screen on the wall • distance to screen: 1 (the screen is always the same distance along the ground, right?) • secant(x) = sec(x) = the “ladder distance” to the screen We have some fancy new vocab terms. Imagine seeing the Vitruvian “TAN GENTleman” projected on the wall. You climb the ladder, making sure you can “SEE, CAN’T you?”. (Yeah, he’s naked… won’t forget the analogy now, will you?) Let’s notice a few things about tangent, the height of the screen. • It starts at 0, and goes infinitely high. You can keep pointing higher and higher on the wall, to get an infinitely large screen! (That’ll cost ya.) • Tangent is just a bigger version of sine! It’s never smaller, and while sine “tops off” as the dome curves in, tangent keeps growing. • Secant starts at 1 (ladder on the floor to the wall) and grows from there • Secant is always longer than tangent. The leaning ladder used to put up the screen must be longer than the screen itself, right? (At enormous sizes, when the ladder is nearly vertical, they’re close. But secant is always a smidge longer.) Remember, the values are percentages. If you’re pointing at a 50-degree angle, tan(50) = 1.19. Your screen is 19% larger than the distance to the wall (the radius of the dome). (Plug in x=0 and check your intuition that tan(0) = 0, and sec(0) = 1.) ## Cotangent/Cosecant: The Ceiling Amazingly enough, your neighbor now decides to build a ceiling on top of your dome, far into the horizon. (What’s with this guy? Oh, the naked-man-on-my-wall incident…) Well, time to build a ramp to the ceiling, and have a little chit chat. You pick an angle to build and work out: • cotangent(x) = cot(x) = how far the ceiling extends before we connect • cosecant(x) = csc(x) = how long we walk on the ramp • the vertical distance traversed is always 1 Tangent/secant describe the wall, and COtangent and COsecant describe the ceiling. Our intuitive facts are similar: • If you pick an angle of 0, your ramp is flat (infinite) and never reachers the ceiling. Bummer. • The shortest “ramp” is when you point 90-degrees straight up. The cotangent is 0 (we didn’t move along the ceiling) and the cosecant is 1 (the “ramp length” is at the minimum). ## Visualize The Connections A short time ago I had zero “intuitive conclusions” about the cosecant. But with the dome/wall/ceiling metaphor, here’s what we see: Whoa, it’s the same triangle, just scaled to reach the wall and ceiling. We have vertical parts (sine, tangent), horizontal parts (cosine, cotangent), and “hypotenuses” (secant, cosecant). (Note: the labels show where each item “goes up to”. Cosecant is the full distance from you to the ceiling.) Now the magic. The triangles have similar facts: From the Pythagorean Theorem (a2 + b2 = c2) we see how the sides of each triangle are linked. And from similarity, ratios like “height to width” must be the same for these triangles. (Intuition: step away from a big triangle. Now it looks smaller in your field of view, but the internal ratios couldn’t have changed.) This is how we find out “sine/cosine = tangent/1”. I’d always tried to memorize these facts, when they just jump out at us when visualized. SOH-CAH-TOA is a nice shortcut, but get a real understanding first! ## Gotcha: Remember Other Angles Psst… don’t over-focus on a single diagram, thinking tangent is always smaller than 1. If we increase the angle, we reach the ceiling before the wall: The Pythagorean/similarity connections are always true, but the relative sizes can vary. (But, you might notice that sine and cosine are always smallest, or tied, since they’re trapped inside the dome. Nice!) ## Summary: What Should We Remember? For most of us, I’d say this is enough: • Trig explains the anatomy of “math-made” objects, such as circles and repeating cycles • The dome/wall/ceiling analogy shows the connections between the trig functions • Trig functions return percentages, that we apply to our specific scenario You don’t need to memorize 12 + cot2 = csc2, except for silly tests that mistake trivia for understanding. In that case, take a minute to draw the dome/wall/ceiling diagram, fill in the labels (a tan gentleman you can see, can’t you?), and create a cheatsheet for yourself. In a follow-up, we’ll learn about graphing, complements, and using Euler’s Formula to find even more connections. ## Appendix: The Original Definition Of Tangent You may see tangent defined as the length of the tangent line from the circle to the x-axis (geometry buffs can work this out). As expected, at the top of the circle (x=90) the tangent line can never reach the x-axis and is infinitely long. I like this intuition because it helps us remember the name “tangent”, and here’s a nice interactive trig guide to explore: Still, it’s critical to put the tangent vertical and recognize it’s just sine projected on the back wall (along with the other triangle connections). ## Appendix: Inverse Functions Trig functions take an angle and return a percentage. sin(30) = .5 means a 30-degree angle is 50% of the max height. The inverse trig functions let us work backwards, and are written sin-1 or arcsin (“arcsine”), and often written asin in various programming languages. If our height is 25% of the dome, what’s our angle? Now what about something exotic, like inverse secant? Often times it’s not available as a calculator function (even the one I built, sigh). Looking at our trig cheatsheet, we find an easy ratio where we can compare secant to 1. For example, secant to 1 (hypotenuse to horizontal) is the same as 1 to cosine: $\displaystyle{\frac{sec}{1} = \frac{1}{cos}}$ Suppose our secant is 3.5, i.e. 350% of the radius of the unit circle. What’s the angle to the wall? \begin{align} \frac{\sec}{1} &= \frac{1}{\cos} = 3.5 \\ \cos &= \frac{1}{3.5} \\ \arccos(\frac{1}{3.5}) &= 73.4 \end{align} ## Appendix: A Few Examples Example: Find the sine of angle x. Ack, what a boring question. Instead of “find the sine” think, “What’s the height as a percentage of the max (the hypotenuse)?”. First, notice the triangle is “backwards”. That’s ok. It still has a height, in green. What’s the max height? By the Pythagorean theorem, we know \begin{align} 3^2 + 4^2 &= \text{hypotenuse}^2 \\ 25 &= \text{hypotenuse}^2 \\ 5 &= \text{hypotenuse} \end{align} Ok! The sine is the height as a percentage of the max, which is 3/5 or .60. Follow-up: Find the angle. Of course. We have a few ways. Now that we know sine = .60, we can just do: $\displaystyle{\arcsin(.60) = 36.9}$ Here’s another approach. Instead of using sine, notice the triangle is “up against the wall”, so tangent is an option. The height is 3, the distance to the wall is 4, so the tangent height is 3/4 or 75%. We can use arctangent to turn the percentage back into an angle: $\displaystyle{\tan = \frac{3}{4} = .75 }$ $\displaystyle{\arctan(.75) = 36.9}$ Example: Can you make it to shore? You’re on a boat with enough fuel to sail 2 miles. You’re currently .25 miles from shore. What’s the largest angle you could use and still reach land? Also, the only reference available is Hubert’s Compendium of Arccosines, 3rd Ed. (Truly, a hellish voyage.) Ok. Here, we can visualize the beach as the “wall” and the “ladder distance” to the wall is the secant. First, we need to normalize everything in terms of percentages. We have 2 / .25 = 8 “hypotenuse units” worth of fuel. So, the largest secant we could allow is 8 times the distance to the wall. We’d like to ask “What angle has a secant of 8?”. But we can’t, since we only have a book of arccosines. We use our cheatsheet diagram to relate secant to cosine: Ah, I see that “sec/1 = 1/cos”, so \begin{align} \sec &= \frac{1}{\cos} = 8 \\ \cos &= \frac{1}{8} \\ \arccos(\frac{1}{8}) &= 82.8 \end{align} A secant of 8 implies a cosine of 1/8. The angle with a cosine of 1/8 is arccos(1/8) = 82.8 degrees, the largest we can afford. Not too bad, right? Before the dome/wall/ceiling analogy, I’d be drowning in a mess of computations. Visualizing the scenario makes it simple, even fun, to see which trig buddy can help us out. In your problem, think: am I interested in the dome (sin/cos), the wall (tan/sec), or the ceiling (cot/csc)? Happy math. Update: The owner of Grey Matters put together interactive diagrams for the analogies (drag the slider on the left to change the angle): Thanks!	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 7, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8973981142044067, "perplexity": 2631.48139060192}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-30/segments/1469257824994.73/warc/CC-MAIN-20160723071024-00295-ip-10-185-27-174.ec2.internal.warc.gz"}
http://physics.stackexchange.com/questions/45158/about-the-gauge-invariance-of-chern-simons-theory-in-local-coordinates	# About the gauge invariance of Chern-Simons' theory (in local coordinates) I am aware of the differential form language proof of the fact that for arbitrary gauge transformations the Chern-Simons' term shifts by a WZW term (on the boundary). But I am getting confused if in local coordinates I try to prove that under infinitesimal gauge transformations the Chern-Simons' term is invariant (may be upto total derivatives) So I took my infinitesimal gauge transformation as $\delta A^a_\mu = \partial _\mu \epsilon ^a + f^{abc}A_\mu^b \epsilon ^c$ where my structure constants $f^{abc}$ are totally antisymmetric and cyclic. Then I look at the two terms that I have in the CS form, $\epsilon^{\mu \nu \lambda}A^a_\mu \partial_\nu A^a_\lambda$ and $\epsilon^{\mu \nu \lambda}f^{abc}A^a_\mu A^b_\nu A^c_\lambda$ and I vary them infinitesimally to get, $\delta (\epsilon^{\mu \nu \lambda}A^a_\mu \partial_\nu A^a_\lambda ) = 2\epsilon^{\mu \nu \lambda}( \partial_\mu \epsilon ^a \partial _\nu A^a_\lambda + f^{abc}A_\mu ^b \partial _\nu A_\lambda ^a \epsilon ^c)$ $\delta (\epsilon^{\mu \nu \lambda}f^{abc}A^a_\mu A^b_\nu A^c_\lambda) = 3\epsilon^{\mu \nu \lambda}f^{abc} ( \partial _\mu \epsilon^a A_\nu ^b A_\lambda ^c + f^{adf} A_\mu ^d A_\nu ^b A_\lambda ^c \epsilon ^f)$ • Now I can't see how any linear combination of the above two terms can make their combined variation 0 (or a total derivative). I would like to know as to what am I missing here. - Use the Jacobi identity $f^{abc}f^{adf}+f^{adb}f^{acf}+f^{acd}f^{abf}=0$ to the last term.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9653164148330688, "perplexity": 344.8349587930589}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-07/segments/1454701162938.42/warc/CC-MAIN-20160205193922-00309-ip-10-236-182-209.ec2.internal.warc.gz"}
http://mathoverflow.net/questions/87600/calculate-all-the-equivalent-martingale-measures?sort=oldest	# calculate all the equivalent martingale measures Under the assumption of no arbitrage without vanish risk, in an incomplete market $(\Omega,{\cal F}, P)$, the set of equivalent martingale measure is NOT empty, i.e. $\mathcal{P} = \{Q: Q \sim P\}\neq \emptyset$ My question is: in the following simplified market with one stock which is driving by two independent Brownian Motions and one bond, i.e. $$dS_t = S_t(\mu dt + \sigma_1 dW_1(t) + \sigma_2 dW_2(t))$$ $$dB_t = rB_tdt, \mbox{ } B_0 = 1$$ How to calculate all the equivalent martingale ${\cal P}.$ We suppose that $\mu,\sigma_1,\sigma_2, r$ are constants. One approach in my mind is using another stock to complete the market, i.e. we suppose there is another stock $\tilde{S}$ with parameters, $\tilde{\mu}, \tilde{\sigma_1},\tilde{ \sigma_2}$ such that $$d\tilde{S_t} = \tilde{S_t}(\tilde{\mu} dt + \tilde{\sigma_1} dW_1(t) + \tilde{\sigma_2} dW_2(t)).$$ Then, following the classic method, we could get the equivalent martingale measures described by parameters, $\mu,\sigma_1,\sigma_2, r, \tilde{\mu}, \tilde{\sigma_1},\tilde{ \sigma_2}.$ But, how could I know the equivalent martingale measure obtained by above approach are the set of all the equivalent martingale measures in this financial market? Any suggestion, reference books, or papers are welcome. Thanks. - The question might be suitable for the sister stackexchange site devoted to Quantitative Finance: quant.stackexchange.com – Andrey Rekalo Feb 5 '12 at 21:21 One possible approach is to use the fact that the density process $\left. Z_t =\frac{d\mathcal{Q}}{d\mathcal{P}} \right\vert_{\mathcal{F}_t}$ for every equivalent local martingale measure $\mathcal{Q}$ is a true martingale in the Brownian filtration and you can characterize it via the martingale representation theorem. As a guiding example you may look e.g. on Appendix A of R. Frey's paper "Derivative Asset Analysis in Models with Level Dependent and Stochastic Volatility", CWI Quaterly 10, no 1 (special issue on the Mathematics of Finance) p 1-34 which he links on his webpage: http://www.math.uni-leipzig.de/~frey/vol_survey.ps	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9345971941947937, "perplexity": 416.55599132754793}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-11/segments/1424936465487.60/warc/CC-MAIN-20150226074105-00326-ip-10-28-5-156.ec2.internal.warc.gz"}
http://www.thecodingforums.com/threads/need-help-dsn-connection-string.67328/	# Need help : DSN connection string Discussion in 'ASP .Net' started by Tee, Nov 21, 2003. 1. ### TeeGuest Hi, I need some help here for DSN connection string. I know it's not recommended to use DSN, even I dont like it as well ... but for now, my situation is I am using a shared hosting. I do not have write access to my web root folder, I have a folder specialy for database. I am currently using access, it is just for testing purpose. here's the info: ms access database password : testdb dsn name : testdb can anyone tell me what is the connection string ? thanks, Tee Tee, Nov 21, 2003 2. ### Dino Chiesa [Microsoft]Guest You don't need write access to c:\, to use DSN-less connection strings. To see sample connection strings, try www.connectionstrings.com eg, "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=\dbdir\dbfile.mdb;User "Tee" <> wrote in message news:... > Hi, > > I need some help here for DSN connection string. > I know it's not recommended to use DSN, even I dont like it as well ... > but for now, my situation is I am using a shared hosting. I do not have > write access to my web root folder, I have a folder specialy for database. > I am currently using access, it is just for testing purpose. > > here's the info: > > ms access database password : testdb > dsn name : testdb > > can anyone tell me what is the connection string ? > > thanks, > Tee > > Dino Chiesa [Microsoft], Nov 21, 2003 3. ### TeeGuest I know about DNS less connection string ... but now the problem is the database folder is not inside the wwwroot ... if I really have to get to that folder, I must use ../db/dbfile.mdb ... but now another problem comes, I cannot exit the top root by using ../ ... and if I place the database inside my wwwroot folder, I don't have write access. I need write data to the database as well. Thanks, Tee "Dino Chiesa [Microsoft]" <> wrote in message news:... > You don't need write access to c:\, to use DSN-less connection strings. > > To see sample connection strings, try > www.connectionstrings.com > > eg, > "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=\dbdir\dbfile.mdb;User > > > "Tee" <> wrote in message > news:... > > Hi, > > > > I need some help here for DSN connection string. > > I know it's not recommended to use DSN, even I dont like it as well ... > > but for now, my situation is I am using a shared hosting. I do not have > > write access to my web root folder, I have a folder specialy for database. > > I am currently using access, it is just for testing purpose. > > > > here's the info: > > > > ms access database password : testdb > > dsn name : testdb > > > > can anyone tell me what is the connection string ? > > > > thanks, > > Tee > > > > > > Tee, Nov 21, 2003 4. ### Dino Chiesa [Microsoft]Guest can you not use string manipulation to build the proper folder name? or Server.MapPath() or .. Your hoster maybe has a FAQ somewhere illustrating how to do this on that site? -D "Tee" <> wrote in message news:... > I know about DNS less connection string ... but now the problem is the > database folder is not inside the wwwroot ... > if I really have to get to that folder, I must use ../db/dbfile.mdb ... > but now another problem comes, I cannot exit the top root by using ../ ... > and if I place the database inside my wwwroot folder, I don't have write > access. I need write data to the database as well. > > Thanks, > Tee > > > "Dino Chiesa [Microsoft]" <> wrote in message > news:... > > You don't need write access to c:\, to use DSN-less connection strings. > > > > To see sample connection strings, try > > www.connectionstrings.com > > > > eg, > > "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=\dbdir\dbfile.mdb;User > > > > > > "Tee" <> wrote in message > > news:... > > > Hi, > > > > > > I need some help here for DSN connection string. > > > I know it's not recommended to use DSN, even I dont like it as well .... > > > but for now, my situation is I am using a shared hosting. I do not have > > > write access to my web root folder, I have a folder specialy for > database. > > > I am currently using access, it is just for testing purpose. > > > > > > here's the info: > > > > > > ms access database password : testdb > > > dsn name : testdb > > > > > > can anyone tell me what is the connection string ? > > > > > > thanks, > > > Tee > > > > > > > > > > > > Dino Chiesa [Microsoft], Nov 21, 2003 5. ### TeeGuest I am using server.MapPath ... and it really dont let me exit the root by using ../ ... as now the the db folder & wwwroot folder are on the same level ... sorry if you couldn't understand what I meant ... it is, when I ftp login, I see 2 folder, wwwroot & db ... so I cannot exit wwwroot and read data in db folder by using ../db/data.mdb .... thanks. "Dino Chiesa [Microsoft]" <> wrote in message news:... > can you not use string manipulation to build the proper folder name? > or Server.MapPath() > or .. > > Your hoster maybe has a FAQ somewhere illustrating how to do this on that > site? > -D > > > "Tee" <> wrote in message > news:... > > I know about DNS less connection string ... but now the problem is the > > database folder is not inside the wwwroot ... > > if I really have to get to that folder, I must use ../db/dbfile.mdb ... > > but now another problem comes, I cannot exit the top root by using ../ .... > > and if I place the database inside my wwwroot folder, I don't have write > > access. I need write data to the database as well. > > > > Thanks, > > Tee > > > > > > "Dino Chiesa [Microsoft]" <> wrote in message > > news:... > > > You don't need write access to c:\, to use DSN-less connection strings. > > > > > > To see sample connection strings, try > > > www.connectionstrings.com > > > > > > eg, > > > "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=\dbdir\dbfile.mdb;User > > > > > > > > > "Tee" <> wrote in message > > > news:... > > > > Hi, > > > > > > > > I need some help here for DSN connection string. > > > > I know it's not recommended to use DSN, even I dont like it as well > ... > > > > but for now, my situation is I am using a shared hosting. I do not > have > > > > write access to my web root folder, I have a folder specialy for > > database. > > > > I am currently using access, it is just for testing purpose. > > > > > > > > here's the info: > > > > > > > > ms access database password : testdb > > > > dsn name : testdb > > > > > > > > can anyone tell me what is the connection string ? > > > > > > > > thanks, > > > > Tee > > > > > > > > > > > > > > > > > > > > Tee, Nov 22, 2003 6. ### William LaMartinGuest If you are using the 1.1 version of the framework, then in help look up OBDC Data Sources then Connections. I think this will tell you how to do want you to do. If you are using the 1.0 framework, you will have to download the ODBC .Net Data provider from Microsoft at "Tee" <> wrote in message news:... > Hi, > > I need some help here for DSN connection string. > I know it's not recommended to use DSN, even I dont like it as well ... > but for now, my situation is I am using a shared hosting. I do not have > write access to my web root folder, I have a folder specialy for database. > I am currently using access, it is just for testing purpose. > > here's the info: > > ms access database password : testdb > dsn name : testdb > > can anyone tell me what is the connection string ? > > thanks, > Tee > > William LaMartin, Nov 22, 2003 7. ### Kevin SpencerGuest All you need to do is find out the absolute file path the the .mdb file and -- Kevin Spencer ..Net Developer Microsoft MVP of lots of little things. "Tee" <> wrote in message news:... > I am using server.MapPath ... and it really dont let me exit the root by > using ../ ... > > as now the the db folder & wwwroot folder are on the same level ... sorry if > you couldn't understand what I meant ... > > it is, when I ftp login, I see 2 folder, wwwroot & db ... > so I cannot exit wwwroot and read data in db folder by using .../db/data.mdb > ... > > > thanks. > > > > > "Dino Chiesa [Microsoft]" <> wrote in message > news:... > > can you not use string manipulation to build the proper folder name? > > or Server.MapPath() > > or .. > > > > Your hoster maybe has a FAQ somewhere illustrating how to do this on that > > site? > > -D > > > > > > "Tee" <> wrote in message > > news:... > > > I know about DNS less connection string ... but now the problem is the > > > database folder is not inside the wwwroot ... > > > if I really have to get to that folder, I must use ../db/dbfile.mdb .... > > > but now another problem comes, I cannot exit the top root by using ../ > ... > > > and if I place the database inside my wwwroot folder, I don't have write > > > access. I need write data to the database as well. > > > > > > Thanks, > > > Tee > > > > > > > > > "Dino Chiesa [Microsoft]" <> wrote in message > > > news:... > > > > You don't need write access to c:\, to use DSN-less connection > strings. > > > > > > > > To see sample connection strings, try > > > > www.connectionstrings.com > > > > > > > > eg, > > > > "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=\dbdir\dbfile.mdb;User > > > > > > > > > > > > "Tee" <> wrote in message > > > > news:... > > > > > Hi, > > > > > > > > > > I need some help here for DSN connection string. > > > > > I know it's not recommended to use DSN, even I dont like it as well > > ... > > > > > but for now, my situation is I am using a shared hosting. I do not > > have > > > > > write access to my web root folder, I have a folder specialy for > > > database. > > > > > I am currently using access, it is just for testing purpose. > > > > > > > > > > here's the info: > > > > > > > > > > ms access database password : testdb > > > > > dsn name : testdb > > > > > > > > > > can anyone tell me what is the connection string ? > > > > > > > > > > thanks, > > > > > Tee > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Kevin Spencer, Nov 22, 2003 8. ### William LaMartinGuest That should have read ODBC Data Sources "William LaMartin" <> wrote in message news:... > If you are using the 1.1 version of the framework, then in help look up OBDC > Data Sources then Connections. I think this will tell you how to do want > you to do. > > If you are using the 1.0 framework, you will have to download the ODBC ..Net > Data provider from Microsoft at > > > > "Tee" <> wrote in message > news:... > > Hi, > > > > I need some help here for DSN connection string. > > I know it's not recommended to use DSN, even I dont like it as well ... > > but for now, my situation is I am using a shared hosting. I do not have > > write access to my web root folder, I have a folder specialy for database. > > I am currently using access, it is just for testing purpose. > > > > here's the info: > > > > ms access database password : testdb > > dsn name : testdb > > > > can anyone tell me what is the connection string ? > > > > thanks, > > Tee > > > > > > William LaMartin, Nov 23, 2003 1. ### OK. This is silly. Do I need a DSN on the server for a SQL connection? Hugh G. Johnson, in forum: ASP .Net Replies: 1 Views: 370 Greg Burns Sep 7, 2004 Replies: 1 Views: 6,004 Jeff Dillon Apr 26, 2006 3. ### oleDbConnection with DSN less connection string? Michael Appelmans, in forum: ASP .Net Web Controls Replies: 0 Views: 185 Michael Appelmans Jun 4, 2004 4. ### System DSN Faster Than File DSN! Arpan, in forum: ASP General Replies: 7 Views: 250 5. ### DSN-Less Connection Help SIMON GARE, in forum: ASP General Replies: 1 Views: 97 Bob Barrows [MVP] Mar 10, 2006	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8308377265930176, "perplexity": 7812.5423200970345}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-23/segments/1404776440207.64/warc/CC-MAIN-20140707234040-00021-ip-10-180-212-248.ec2.internal.warc.gz"}
https://stats.stackexchange.com/questions/154830/10-fold-cross-validation-vs-leave-one-out-cross-validation?noredirect=1	# 10-fold Cross-validation vs leave-one-out cross-validation I'm doing nested cross-validation. I have read that leave-one-out cross-validation can be biased (don't remember why). Is it better to use 10-fold cross-validation or leave-one-out cross-validation apart from the longer runtime for leave-one-out cross-validation? • Do you remember where you read that? May 31, 2015 at 12:41 • Have you seen this post about bias? Also, this answer has a quote from a very good book that recommends 5-fold or 10-fold cross validation. May 31, 2015 at 12:46 • This post is a little related. May 31, 2015 at 12:49 • Thank you. So all in all it can be said that I should go with 10-fold CV instead of leave-one-out CV? Does this also hold for a small dataset? May 31, 2015 at 21:06 • @Thomas, when your dataset gets too small you end up nearly doing LOO-CV so the benefit of 10-fold CV diminishes as your dataset size decreases. Jun 4, 2015 at 19:03 Cross-validation gives a pessimistically biased estimate of performance because most statistical models will improve if the training set is made larger. This means that k-fold cross-validation estimates the performance of a model trained on a dataset $$100\times\frac{(k-1)}{k}\%$$ of the available data, rather than on 100% of it. So if you perform cross-validation to estimate performance, and then use a model trained on all of the data for operational use, it will perform slightly better than the cross-validation estimate suggests. Leave-one-out cross-validation is approximately unbiased, because the difference in size between the training set used in each fold and the entire dataset is only a single pattern. There is a paper on this by Luntz and Brailovsky (in Russian). Luntz, Aleksandr, and Viktor Brailovsky. "On estimation of characters obtained in statistical procedure of recognition." Technicheskaya Kibernetica 3.6 (1969): 6–12. Lachenbruch,Peter A., and Mickey, M. Ray. "Estimation of Error Rates in Discriminant Analysis." Technometrics 10.1 (1968): 1–11. However, while leave-one-out cross-validation is approximately unbiased, it tends to have a high variance (so you would get very different estimates if you repeated the estimate with different initial samples of data from the same distribution). As the error of the estimator is a combination of bias and variance, whether leave-one-out cross-validation is better than 10-fold cross-validation depends on both quantities. Now the variance in fitting the model tends to be higher if it is fitted to a small dataset (as it is more sensitive to any noise/sampling artifacts in the particular training sample used). This means that 10-fold cross-validation is likely to have a high variance (as well as a higher bias) if you only have a limited amount of data, as the size of the training set will be smaller than for LOOCV. So k-fold cross-validation can have variance issues as well, but for a different reason. This is why LOOCV is often better when the size of the dataset is small. However, the main reason for using LOOCV in my opinion is that it is computationally inexpensive for some models (such as linear regression, most kernel methods, nearest-neighbour classifiers, etc.), and unless the dataset were very small, I would use 10-fold cross-validation if it fitted in my computational budget, or better still, bootstrap estimation and bagging. • +1 for the obscure 1969 Russian reference! Do you have a good reference for LOOCV having high variance? This is stated in Hastie et al but I am not sure I am 100% convinced by the argument and I haven't seen empirical demonstrations (simulations). Mar 1, 2017 at 8:43 • yes, I don't think I agree with it though, as it assumes that the model is stable under the perturbations caused by deleting the test samples, which is only likely to approach being true if you have a very large dataset (i.e. it is only asymptotically true, but if you had that much data, almost any sensible performance evaluation scheme would give you the same result). Mar 1, 2017 at 10:46 • +1 (both the post as well as the latest comment - great paper but not to be blinded followed (as any other paper)). May 20, 2017 at 11:11 • @Dikran This topic (of LOOCV having the largest variance) came up again in a separate and quite interesting question: stats.stackexchange.com/questions/280665, you might want to take a look. May 22, 2017 at 6:10 • Here is another simulation stats.stackexchange.com/a/357749 showing that the variance of CV estimator decreases with the number of folds and LOOCV has the same (or lower) variance as 10-fold. Another simulation linked in my comment above showed another example where variance was decreasing with $k$, and was the lowest for LOOCV. By now I am really curious to see any simulation where the variance would increase with the number of folds. I am also starting to be rather skeptical that it can happen in practice. Jul 19, 2018 at 20:35 In my opinion, leave one out cross validation is better when you have a small set of training data. In this case, you can't really make 10 folds to make predictions on using the rest of your data to train the model. If you have a large amount of training data on the other hand, 10-fold cross validation would be a better bet, because there will be too many iterations for leave one out cross-validation, and considering these many results to tune your hyperparameters might not be such a good idea. According to ISL, there is always a bias-variance trade-off between doing leave one out and k fold cross validation. In LOOCV(leave one out CV), you get estimates of test error with lower bias, and higher variance because each training set contains n-1 examples, which means that you are using almost the entire training set in each iteration. This leads to higher variance too, because there is a lot of overlap between training sets, and thus the test error estimates are highly correlated, which means that the mean value of the test error estimate will have higher variance. The opposite is true with k-fold CV, because there is relatively less overlap between training sets, thus the test error estimates are less correlated, as a result of which the mean test error value won't have as much variance as LOOCV. • "...you get estimates of test error with lower bias, and higher variance because each training set contains n-1 examples, which means that you are using almost the entire training set in each iteration. This leads to higher variance too, because there is a lot of overlap between training sets, and thus the test error estimates are highly correlated..." Are these two separate reasons or are you just saying the same thing twice? Nov 10, 2021 at 22:09 The existing answers focus on getting good estimates of the out of sample prediction error. This is not the only perspective on the LOOCV versus K-fold CV decision. In particular, some readers may believe there is a true model and may wish to recover it. In this case, Shao 1993 famously showed that for linear models, LOOCV is inconsistent for recovering the true model and something resembling K-fold CV is consistent. (Shao considered a train-test split where the $$n_{test}/n_{train}$$ goes to 1, i.e. the test set dominates.) Model selection is a deep and confusing topic, so let me add a couple of references to related discussions. • A related discussion here on LASSO reinforces this dichotomy of prediction vs inference and has interesting, thought-provoking comments about LASSO and CV in specific. • This site has maybe hundreds of related threads that describe AIC and BIC. In some cases, these are asymptotically equivalent to LOOCV (AIC) and K-fold CV (BIC) (More info and orignal sources in this answer: https://stats.stackexchange.com/a/414610/86176). These threads reinforce what I wrote above, because like LOOCV, AIC emphasizes prediction. Like K-fold, BIC emphasizes selecting the true model. Yuhong Yang showed that no procedure can be optimal for both purposes. • Rob Hyndman has a useful cross-validation overview here mentioning AIC, BIC, LOO, and leave-more-out CV. His position is that consistency in model selection is irrelevant because the true model is rarely in the set under consideration.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 2, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6356448531150818, "perplexity": 756.035446971779}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-27/segments/1656104655865.86/warc/CC-MAIN-20220705235755-20220706025755-00399.warc.gz"}
https://quantgirl.blog/fan-charts/	# Fan Charts Starting on 7 November 2019, the Bank of England‘s Inflation Report became the Monetary Policy Report. This quarterly publication communicates economic analysis and inflation projections that the Monetary Policy Committee uses to make its interest rate decisions. Since 1996 the Bank of England (BoE) inflation forecast has been published as a probability distribution and presented in what is now known as ‘the fan chart’. The first fan charts that were published by the BoE can be found in its Inflation Report-February 1996. A digital copy of the printed report (which used to be sold for £3!) can be found here (see page 48 for the charts). In this post, we will review the ideas behind the fan charts, as well as details on how they are constructed and interpreted. We will use the fanchart library to plot them with Python! ## Motivation The BoE introduced the fan charts aiming to communicate a more accurate representation of their forecast for medium term inflation. In particular, the charts have two key objectives: • To convey the uncertainty in their forecasts. This is, to focus attention on the the forecast distribution, rather than only on small changes to the central projection. • To promote discussion of the risks to the economic outlook, and thus contribute to a wider debate about economic policy. Fan charts help to make it clear that monetary policy is about making decisions instead of knowing the exact rate of inflation in two years time. ## Choice of the Two-Piece Normal Historical observations showed that inflation outcomes were not symmetrically dispersed around a central value, with the values closer to the centre being more likely than those further away. This led to the choice of the two-piece normal distribution, which can capture asymmetry through a skewness parameter, for the forecast model. As we know, the probability density function (pdf) of the two-piece normal (see my previous post for more details) is defined as $$s(x) := s\left(x; \mu,\sigma_1,\sigma_2\right) = \begin{cases} \dfrac{2}{\sigma_1+\sigma_2}f\left(\dfrac{x-\mu}{\sigma_1}\right), \qquad \mbox{if } x < \mu, \\ \dfrac{2}{\sigma_1+\sigma_2}f\left(\dfrac{x-\mu}{\sigma_2}\right), \qquad \mbox{if } x \geq \mu, \\ \end{cases}$$ where $f: \mathbb{R} \mapsto \mathbb{R}_{+}$ is the pdf of the standard normal distribution. However, the Bank of England uses the following re-parametrisation:$$\sigma_1 = \dfrac{\sigma}{\sqrt{1-\gamma}} ; \qquad \sigma_2 = \dfrac{\sigma}{\sqrt{1+\gamma}},$$ where $\sigma >0$ and $\gamma \in (-1, 1)$. Thus, the pdf of the two-piece normal can be written as$$s(x) := s\left(x; \mu,\sigma,\gamma\right) = \begin{cases} \dfrac{A}{\sqrt{2\pi}\sigma} \exp \left\{ -\dfrac{1-\gamma}{2\sigma^2} \left[(x-\mu)^2\right] \right\}, \qquad \mbox{if } x < \mu, \\ \dfrac{A}{\sqrt{2\pi}\sigma} \exp \left\{ -\dfrac{1+\gamma}{2\sigma^2} \left[(x-\mu)^2\right] \right\}, \qquad \mbox{if } x \geq \mu, \\ \end{cases}$$ where $A = \dfrac{2}{\frac{1}{\sqrt{1-\gamma}}+\frac{1}{\sqrt{1+\gamma}}}$. So, in order to derive the forecast distribution for each quarter ahed, three parameters need to be estimated: • $\mu$ : a measure of the central tendency for inflation • $\sigma$ : a view on the degree of uncertainty • $\gamma$ : a view on the balance of the risks, to get a measure of the skew. Once these parameters are set, the two-piece normal is completely defined. BoE publishes these parameters as part of its quarterly report as: • Mode • Uncertainty • Skewness You can download all the data related to the fan charts by using the “Download the chart slides and data (ZIP)” option in the Monetary Policy Report website. ## Python Implementation We will use the fanchart library to reproduce the fan charts. This library contains a copy of the BoE data and parameters (already in the format required by the functions) as of November 2019. from fanchart.plot import * ### Quarter Fan Chart First, we plot a variant of the fan charts which uses only the projection associated to a single quarter. For this purpose, we will use the function fan_single which provides functionality for two kinds of charts, namely the probability density function (pdf) and the cumulative distribution function (cdf). In order to use the fan_single function, we need to provide: • The parameters $\mu, \sigma, \gamma$ (loc, sigma, and gamma) for the two-piece distribution corresponding to the quarterly projection. • A set of probabilities which define the bands of the chart • The kind of plot, namely ‘pdf’ or ‘cdf ‘ For illustration purposes, we use the parameters corresponding to the projection for 2020-10-01. You can find parameters corresponding to other dates here. Remember that the parameters are called mode, uncertainty, and skewness by the BoE. prob = [0.05, 0.20, 0.35, 0.65,0.80, 0.95] fan_single(loc=1.51, sigma=1.34, gamma=0.0, p=prob, kind='pdf'); fan_single(loc=1.51, sigma=1.34, gamma=0.0, p=prob, kind='cdf'); prob = np.arange(0.10, 1, 0.05) fan_single(loc=1.51, sigma=1.34, gamma=0.0, p=prob, kind='pdf'); fan_single(loc=1.51, sigma=1.34, gamma=0.0, p=prob, kind='cdf'); ### Projection Fan Chart Now, we will plot the fan chart that illustrates the entire projection ahead. For this we will use the function fan which requires: • A data frame containing the parameters $\mu, \sigma, \gamma$ (loc, sigma, and gamma) for every quarter in the projection. You can load the parameters corresponding to the Nov-2019 Report from the fanchart library. • A data frame with the observed historical inflation. This serves to produce the solid line before the fan part. You can load the historical data corresponding to the Nov-2019 Report from the fanchart library. • A set of probabilities which define the bands of the chart. history = load_boe_history() probs = [0.05, 0.20, 0.35, 0.65,0.80, 0.95] fan(data=parameters, p=probs, historic=history[history.Date >='2015'].iloc[::3,]); probs = np.arange(0.10, 1, 0.05) fan(data=parameters, p=probs, historic=history[history.Date >= '2015'].iloc[::3,]); Note that at any particular point in the forecast period (which has a grey background) the shading of the bands gets lighter as the probability of inflation lying further away from the central projection decreases. Besides, as predictions become increasingly uncertain over time, these forecast ranges spread out, creating the distinctive”fan” or wedge shapes which originated the “fan chart” term. ### Surface Fan Chart As we mentioned, uncertainty increases over time so we can think of looking at the whole density function over time. This is done in the following three-dimensional chart, which includes the probability density on the z-axis.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8205758333206177, "perplexity": 1678.5509165297094}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662587158.57/warc/CC-MAIN-20220525120449-20220525150449-00658.warc.gz"}
https://www.physicsforums.com/threads/a-power-series-question.84456/	# A power series question 1. Aug 7, 2005 ### complexhuman Hi Assuming tan(x) is given by a power series with coefficiants (An). How can it be shown that An = 0 whenever n is even. Thanks 2. Aug 7, 2005 ### LeonhardEuler I assume you mean a power series centered about x=0. tan(x) is an odd function, i.e. tan(-x)=-tan(x). If it had nonzero coefficients to its even powered terms this could not be the case. 3. Aug 7, 2005 ### complexhuman thanks a lot :)	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8103822469711304, "perplexity": 2241.405464667891}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-26/segments/1529267864354.27/warc/CC-MAIN-20180622045658-20180622065658-00556.warc.gz"}
https://dsp.stackexchange.com/questions/1930/how-to-calculate-the-gain-in-a-bivariate-fft-in-r	How to calculate the gain in a bivariate fft in R? In Statistica gain is defined as follows: Gain. The gain value is computed by dividing the cross-amplitude value by the spectrum density estimates for one of the two series in the analysis. Consequently, two gain values are computed, which can be interpreted as the standard least squares regression coefficients for the respective frequencies. However, spec.pgram (the engine behind spectrum) in R does not return the cross-amplitude value (as far as I can tell). How can I calculate gain for these signals? Example: makewave <- function(freq,phase,amp,Nsamples=lengthsamplerate,samplerate,time=Nsamples/samplerate,as.time.series=TRUE) { time <- Nsamples/samplerate phase <- phase(2pi)/180 wavetimes <- seq(0+phase,timefreqpi2+phase,length.out=Nsamples) #plot(1:samples/samplerate,ampsin(wavetimes),type="l",xlab="Time") if (as.time.series) {res <- ts(ampsin(wavetimes),deltat=1/samplerate)} else {res <- amp*sin(wavetimes)} return(res) } signal1 <- makewave(15,30,1,180,60) signal2 <- makewave(15.01,60,1,180,60) signal.union <- ts.union(signal1,signal2) sp <- spectrum(signal.union,span=c(3),taper=0) plot(sp) plot(sp,plot.type="phase") plot(sp,plot.type="coh") • I'm sorry if this question is too simple for this site. If so, I'll delete it. – russellpierce Apr 3 '12 at 22:04 • It's not too simple, it's just not very clear- at least to me. What do you mean by "bivariate fft"? It looks like you are calculating the fft of two signals added together. Is that what "bivariate fft" means? What does "cross-amplitude value" mean? – Jim Clay Apr 4 '12 at 1:10 • @JimClay I believe that bivariate FFT is simply a two-dimensional FFT. – Phonon Apr 4 '12 at 1:44 • "The cross amplitude values are computed as the square root of the sum of the squared cross-density and quad-density values. The cross-amplitude can be interpreted as a measure of covariance between the respective frequency components in the two series." (documentation.statsoft.com/STATISTICAHelp.aspx?path=TimeSeries/…) – Jim Clay Apr 4 '12 at 13:33 • I am/was shaky on the correct terminology. I have two signals, and I want to compare them to see how much the 2nd matches the first (coh), how much the 2nd lags behind the 1st (phase), and the extent to which the 2nd is under/overshooting the peak amplitudes of the 1st. – russellpierce Apr 4 '12 at 15:55 1 Answer I am/was shaky on the correct terminology. I have two signals, and I want to compare them to see how much the 2nd matches the first (coh), how much the 2nd lags behind the 1st (phase) Normalized cross-correlations are good at that. I don't know what the relevant command would be in Statistica, but in Matlab you would use the command xcorr. and the extent to which the 2nd is under/overshooting the peak amplitudes of the 1st. To answer that in a useful way it would help a great deal to see the signals that you are talking about. Are you just interested in the peaks, or the signal in general? If you are talking about the signal in general then you could time-align the signals using the information from your cross-correlation, and then divide one of the signals by the other. If you are just interested in the peaks you could do the same and then just extract the results at the peak locations. • I am interested in the power in each FFT bin in relation to the power in the other bin. Statistica reports some kind of ratio here as "gain", but I am not sure how it is calculated. I'll provide sample data later today. – russellpierce Apr 12 '12 at 16:32	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8343054056167603, "perplexity": 815.8064724023293}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610704799711.94/warc/CC-MAIN-20210126073722-20210126103722-00363.warc.gz"}
https://www.handsonprogramming.io/blog/2018/07/unicode-primer/	When we first start out programming we don’t really care about character encoding. A string is a string, and as long as it works and behaves as expected so there is no reason to worry about it. Sooner or later we will run into character encoding issues. The common wisdom is to switch every character encoding option you can find to UTF-8 and then hope for the best. This works up to a point, but we’re not really prepared for anything more complex than debugging database error messages or figuring out why your website isn’t rendering text properly. I have found very interesting and handy Unicode cheat sheets, which can help you to be a better programmer. You can download the PDF here.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5204967856407166, "perplexity": 526.7808780604543}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-49/segments/1669446711286.17/warc/CC-MAIN-20221208082315-20221208112315-00137.warc.gz"}
https://web2.0calc.com/questions/knowing-the-diameter-of-6-feet-what-would-be-the-circumference	+0 # Knowing the diameter of 6 feet, what would be the circumference? 0 148 1 Knowing the diameter of 6 feet, what would be the circumference? Guest Jun 5, 2017 #1 +1 $$\pi * d$$ $$\pi 6$$ $$6\pi$$ 6π feet! Of course, this is assuming that you're talking about a circle. Guest Jun 6, 2017 edited by Guest Jun 6, 2017 Sort: #1 +1 $$\pi d$$ $$\pi *6$$ $$6\pi$$ 6π feet! Of course, this is assuming that you're talking about a circle. Guest Jun 6, 2017 edited by Guest Jun 6, 2017 ### 5 Online Users We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners. See details	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8698651194572449, "perplexity": 3520.777359707021}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-13/segments/1521257649961.11/warc/CC-MAIN-20180324073738-20180324093738-00451.warc.gz"}
https://socratic.org/questions/how-do-you-simplify-16-1-2-2	Algebra Topics # How do you simplify (-16)^(-1/2) ? Mar 28, 2016 $\pm \frac{1}{4 i}$ #### Explanation: Consider the example ${x}^{- \frac{1}{2}}$. This is the same as $\frac{1}{\sqrt{x}}$ Now use this approach for your question. $\text{ } {\left(- 16\right)}^{\frac{1}{2}} = \frac{1}{\sqrt{- 16}}$ Write $- 16 \text{ as } - 1 \times 16$ giving $\text{ } \frac{1}{\sqrt{16} \times \sqrt{- 1}}$ The square root of negative 1 gives rise to the complex number context. So we have: $\text{ } \frac{1}{\pm 4} \times \frac{1}{i}$ $\text{ } \pm \frac{1}{4 i}$ '~~~~~~~~~~~~~~~~~~~~~~~~~ If the question had been $- {\left(16\right)}^{- \frac{1}{2}}$ Then the solution would have been: $- \frac{1}{4}$ ##### Impact of this question 2155 views around the world	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 10, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9403823018074036, "perplexity": 1512.9677159640285}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-16/segments/1585371893683.94/warc/CC-MAIN-20200410075105-20200410105605-00055.warc.gz"}