What determines the current in the circuit realizing the voltage-controlled current source?

Question: What determines the current in the circuit with Ideal operation amplifier realizing the voltage-controlled current source?
Comment: There is no generic schematic for what you appear to allude to hence, you need to post a specific schematic.
Comment: Not sure I understand your question. A VCCS has a current determined by the sense voltage, obviously. If it's ideal there would not be any other consumption.
Comment: The operational amplifier output pin? Ideal op amps are usually modeled with VCVS's on the 'inside'\
Answer: Maybe you can look into a 'Current Mirror' circuit. Here, you would typically use the current through a resistor (which is dependent on the voltage across the resistor) to supply an equally large current to other circuitry, buffered by a transistor. Thus, you would have a voltage-controlled current source - which is also utilized in Opamps
Answer: A typical example of a voltage-controlled current source (VCCS) is a common-emitter stage with emitter resistor R. Usually, it is connected in the negative feedback loop of an op-amp follower. The current is determined by the input voltage Vin and the emitter resistance Re (I = Vin/Re).
Another example, in addition to the current mirror VCCS: Do you know what an op-amp inverting amplifier is? If so, the input voltage Vin and the input resistor R1 determine the current I = Vin/R1 that flows through the output resistor R2 (the load). The disadvantage of this circuit solution is that the load is not connected to the real ground; but still it is connected to the virtual ground (the op-amp inverting input).
The Howland current source (pump) does not have this disadvantage. There both the input voltage source and load are real grounded.
And finally, if the load has (almost) zero resistance, you can make the simplest VCCS consisting of... only a resistor R in series to the input voltage source. The current is (approximately) determined by the input voltage Vin and the resistance R according to Ohm's law ( I = Vin/R).
See also How do we create current sources?


What are the advantages/disadvatages of hashing over encryption?

Question: I know that hashing is a one way function and encrypted messages could be retrieved if you know the corresponding key to which you encrypted the message. Other than the ability to retrieve, what advantages/disadvantages are there in hashing over encryption?
Comment: There is no "advantage". They serve completely different purposes.
Answer: As has been mentioned, hashing and encryption serve different purposes, so this question would be better phrased with an application in mind. For a real life example that is commonly used, a website developer might ask: "I am creating a website where users need a username and password to login. Should I store the passwords in plain text somewhere, should I encrypt the passwords, or should I hash them?" The answer to this question will depend on what the website is for and who the users are, but typically it goes like this:

Plain Text Passwords: this should usually be avoided, except for extremely low security sites where the passwords are auto-generated. If the users are allowed to create their own passwords, you should just about never store them in plain-text, because some users will inevitably use the same password for this site as they would for sites with high-security, for example their bank accounts or other email accounts where bank account password reset emails would be sent to.
Encrypt the Passwords: this is MUCH better than plain text passwords, however someone will always have the ability to decrypt the passwords. This is because in order for the web server to authenticate the passwords, it must be able to decrypt the passwords which means that the decryption key must be stored somewhere the server can access. Consequently, anyone with access to the server will be able to decrypt the passwords as well. That person might normally be the web developer or an IT admin who is trusted, but it's usually best to not have anyone be able to decrypt the passwords. Furthermore, if the server is somehow compromised, then the hacker can decrypt everyone's password.
Hashing the Passwords: this is typically the best method since even if the server is compromised, the passwords are still protected (within reason). The main disadvantage of this is that it is not possible to recover a password; you can only reset your password.

Moral: if your bank has a "Forgot Password" recovery mechanism on their website, and they email you your password that you forgot instead of resetting it for you, then you should switch banks.
Answer: There is no advantage ,  they serve different purposes as Terry Chia said.
In "log in systems" you want to make sure that if someone manages to "steal" your database the attacker won't be able to actually read the password, but only the hash of the password, since many users use the same passwords for many different sites. Then if an attacker managed to crack stackexchange's database ,  he would be able to use the same password to email, ebanking etc..
Imagine the scenario where what you want is to make sure a message when transmitted from a sender X to a receiver Y ,is received correctly and the receiver Y can verify it was received correctly and none altered the message, also you both have already decided on a key for the hash function.You don't care if an attacker read your message. So you just send the clear-text , with a hash of that clear-text, then the receiver will hash the received clear-text with the same key and if the two hashes are the same he will be able to verify that, the message received was not altered.
All you care is that your receiver can verify it was send by you.
Answer: If you want to think about it in simpler terms: Hashing is like matching a finger print whereas encrypting it is to scramble the message.
Use hashing to determine if the message/file is authentic. Use encryption to protect/hide the content.
Answer: Elaborating on the functions both serve:
Hashing is, as you said, non-reversible. It is also constant. This is why we use it to store passwords. When you set your password for, say, your e-mail, the server never stores it (well, some do, but they deserve a certain degree of public shaming). Instead, (assuming your password is "password") they store h("password"). Now lets say you want to log in. This is where encryption comes into play. You and the server go though something called a Diffie-Helfman key exchange, which lets you exchange a key with the server. Now you use that key to encrypt your password (x = e("password")) and send it to the server. The server, since it has the same key you used to encrypt your password, can perform the function e^-1(x). Now it has the plaintext of your password. If we were talking about Heartbleed, this is is the most likely point for your password to be stolen. Anyway, now the server performs the function h("password") and compares it against the stored password hash it has associated with your username. If the hash they generated from the value you sent them matches the one that they have, they allow you access to your account.


How to find equation of cone's generatrix?

Question: Given canonical cone equation, how to find equation of cone's generatrix?
Comment: Is the differential-geometry tag correct?
Answer: Consider a cone with caconical equation $x^2/a^2+y^2/b^2-z^2/c^2=0$. Generatrix satisfy the cone equation. Point $x=y=z=0$ satisfy the cone equation and thus satisfy the generatrix equation. Point $x=a y=b z=c\sqrt 2 $ satisfy both cone and generatrix equations. Thus, the direction vector for a certain generatrix will be $(a,b,c\sqrt2)$. Similarly, for any point $x=p, y=q, z=c/ab\sqrt{p^2 b^2+q^2 a^2}$ on a cone parametrized by $(p,q)$ there will be a generatrix with equation $px+qy+zc/ab\sqrt{p^2 b^2+q^2 a^2}=0$, or better, with equation $abpx+abqy+cz\sqrt{p^2 b^2+q^2 a^2}=0$. This is the canonical equation of a desired generatrix.


Template hints showing path from cache instead of original file path

Question:
In Vanilla magento2, the file path showing original file path as you can see in below screenshot the file path is showing from vendor after doc root.
In one of my working project where cache path is showing.
I am facing an issue in Xdebug where the debugger is stopping on cache files instead of actual file. Is this related Magneto configuration? If yes, can anyone share your thoughts on this.
Comment: What is the issue?
Comment: @WangGang the main issue is cache path i.e var/view_preprocessed/pub/static should not show in template path. Usually while debugging we don't keep break point in cache file instead we keep it at actual file. Somehow due to this template path issue I have to keep break point at cache file.
Answer: When the minify HTML feature is enabled in your project, Magento will retrieve the phtml template files from the cached directory, specifically located in the var/view_preprocessed/pub/static directory. As a result, when template hints are displayed, they will show the template path from the cache instead of the original file path.
To disable the minify HTML feature, use the following command:
bin/magento config:set dev/template/minify_html 0
Afterward, clear the config cache type to see the changes by running the command:
bin/magento cache:clean config


ANTLR: How to generate lexer and parser with python?

Question: I had a look at the python run time module but I am unsure about creating the python parser and lexer files. I have written the .g files.
Answer: Here are the steps:

Write the grammar.
Run ANTLR to generate the lexer/parser classes.
Compile and run against Python source files to see how you do.

To accomplish anything useful, you'll have to get the code into an AST and then walk the tree.  Did you do that?  What did you get?
Here's a list of available grammars.  It includes Python 3.  How did you grammar compare?
Comment: thanks for your response, I just realised you have to generate the parser with java =.="
Comment: I'd appreciate you voting up and accepting the answer far more than your thanks.
Comment: @duffymo is it possible to generate lexer and parser in the code instead of doing this manually?
Comment: link is not working
Comment: Fixed it for you.  Google could have found you a replacement with a little effort.


Does Google just hate Magento 2...?

Question: We run 5 site on the same Magento platform (2.1.6) and I have recently been trying to optimize the speed of our site using the parameters outlined by Google Page Speed Insights. Having struggled to really eliminate any of the things google dislikes I wanted to see how other Magento 2 site performed. They ALL seem to perform poorly on the PSI analysis. This includes sites developed by Magento Gold developer partners. Any comments would be most appreciated....
Comment: Reality about Gold Partner is far from what you may think. It means nothing in real world. Regarding your question, I did not dig into the topic yet but interesting
Comment: Don't focus on Google Page Speed too much. If some of these points cost too much effort, it's not worth it. Go for the low hanging fruit
Answer: No.
So much for Magento Gold Developer partners. I think they just don't care about PSI. Some don't care about performance benchmarks at all.
Without giving out names I was approached by a client whose site was migrated to M2 from M1 by some Magento partner. They complained about poor TTFB (time to first byte). Turned out they had an extension that adds 300ms to TTFB for any page, cached or uncached.
A fresh copy of Magento 2 with Luma theme and with FPC on scores above 80% which is pretty good. It is when they create a custom theme and add 3rd-party extensions things start to look bad.

Does Google just hate Magento 2...?


"page not found" due to hat character ("^") in a upload file name

Question: I have several uploaded files whose links I have later discovered yield a "page not found" message error, because their name contain the hat character ("^"). Have I to delete and re-upload them after changing their name or is there an option that makes Wordpress to correctly manage their original name?
Comment: In general, all special characters should be avoided in file names. See [this](http://www.mtu.edu/umc/services/web/cms/characters-avoid/)
Comment: I would hardly call that a hat, more like a hand or wing! `^(o.o)^` - Does it include that character in the slug, what does an example slug look like for one of those pages?
Comment: This may not have anything to do with WordPress, and WordPress-- even PHP-- may not be able to do anything about it. You are dealing with, potentially, server and filesystem level issues. Your best approach is to change to file names.
Comment: @Howdy_McGee if the filename is x^2.xls the slug is/wp-content/uploads/2013/02/x2.xls
Comment: Files have been uploaded by others, not mine. And they are many. Moreover, I wonder that WordPress allows to upload a file with a potentially problematic character in its name but it is not able to manage it correctly.
Answer: This is a filter I use to keep my clients from adding special characters to their filenames, should work for you - you'll have to reupload the file though.
<code>/**
 /* Sanitize Uploaded Filenames
 /* @param array $file
 /* @return array $file
 */
function sanitize_file_uploads( $file ){
    $file['name'] = sanitize_file_name($file['name']);
    $file['name'] = preg_replace("/[^a-zA-Z0-9\_\-\.]/", "", $file['name']);
    $file['name'] = strtolower($file['name']);
    add_filter('sanitize_file_name', 'remove_accents');

    return $file;
}
add_filter('wp_handle_upload_prefilter', 'sanitize_file_uploads');
</code>
This function only allows numeric, numbers, underscores, dashes, and periods. It converts it to lowercase and also run it through the accents function.


Unneeded information at beginning of XCode Console output

Question: I know this has probably been asked, but I can't find the answer.
How do I get rid of this from the beginning of my XCode console output? So that it just shows what I intentionally print to the screen?
<code>[Session started at 2011-04-10 18:37:40 +0100.]
GNU gdb 6.3.50-20050815 (Apple version gdb-1510) (Fri Oct 22 04:12:10 UTC 2010)
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "--host=i386-apple-darwin --target=arm-apple-darwin".tty              /dev/ttys001
Loading program into debugger…
Program loaded.
target remote-mobile /tmp/.XcodeGDBRemote-11063-56
Switching to remote-macosx protocol
</code>
Answer: In Xcode 4, change "All output" to "Target Output".
I'm still looking for a solution for Xcode 3 ...
Answer: In response to "where is that?"

Now, if only there were a way to automatically delete all of Apple's asinine legal disclaimers from the top of EVERY SINGLE PIECE OF THEIR SAMPLE CODE.  Ugh!


How to find capture area of an engine inlet?

Question: I tried to relate intake pressure recovery in terms which do not involve efficiency of an inlet and capture area, i was able to formulate pressure recovery without intake efficiency but now i need to find a way to formulate capture area of inlet without without use of intake efficiency and pressure recovery is it possible ? if yes please share.
Answer: It is not so hard, actually.
You need to know the speeds ahead and inside the intake. You can deduce their ratio from the pressure recovery factor, and normally the Mach number inside the intake is between 0.4 and 0.5, so this, combined with your design flight speed, is a good starting point.
In supersonic flow the air is rammed into the intake face, producing a shock. This will be a straight shock in case of a pitot intake or an oblique shock in case of an intake ramp. Use the appropriate shock tables to find the corresponding speed and density ratios.
For subsonic flow you can use a Gedankenexperiment: Your intake is flying through a densely packed array of stream tubes. Some of them will end up inside the intake, others will be pushed aside as they come close to the intake lip and will flow around it. The speeds in those tubes varies between flight speed well ahead of the intake and your eventual intake speed inside the intake. In between, things change continuously in subsonic flow or via shocks in supersonic flow. Now assume that all the air which passes through the intake will have to pass through their corresponding stream tubes, both ahead and inside the intake. No air is allowed to cross between tubes. If the air inside the intake flows faster than flight speed, the flow in the tubes will be accelerated as they approach the engine face, so the intake has to ingest a lot of tubes to keep mass flow the same. Conversely, if flight speed is higher than intake speed, some of the tubes will be pushed aside to get a match between the mass flows ahead and inside the intake. Don't forget to adjust stream tube area for density changes: The change in stream tube cross section has to be inversely proportional to the change in air density as the air inside the steam tube changes speed, like this:
$$\frac{\delta\rho}{\rho}=-Ma^2\cdot\frac{\delta v}{v}$$
Comment: i appreciate your effort in answering the question.thank you. But you told me to deduce the ratio of the speeds using the pressure recovery factor right?  but i wont be knowing the pressure recovery factor . the whole effort is to roughly calculate the pressure recovery Pi which do does not have efficiency. is it possible to calculate the capture area using continuity equation?
Comment: @vbks Yes, the continuity equation is the mathematical expression of the thought experiment outlined above. For the pressure recovery you start with lossless compression and then apply an appropriate reduction. Well-designed intakes have efficiencies of 97-98%, so the loss is small. And you need to know either the speeds or the pressures, or there is no basis for a calculation.


generating solutions to diophantine equation

Question: If I have a solution to say
$$4x_1+3x_2+3x_3+3x_4...+3x_n=4y$$ where $x_i ,y$ are non negative integers can I generate other solutions from my initial solution? And if I can would all solutions follow from this initial one?
Comment: what I am really trying to get at is if my initial solution contains all even integers then would solutions generated contain at least one even integer  because the coefficient in front of $x_1$ is even
Comment: Is it a linear equation you are interested in? If yes, you sould find more solution by finding integer vectors in the "kernel" of this system. Here, it is the space orthogonal to $(4, 3, 3, \dotsc, 3)$ or more precisely the integer lattice living in this orthogonal.
Comment: For your comment, I am not sure it works: take $n=5$, and consider $u=(-3,1,1,1,1)$. Then $4u_1 + 3u_2 +\dotsb + 3u_5 = 0$. Now look at the equation $4x_1 + 3x_2 + \dotsb + 3x_5 = 8$. Then $x = (2, 0, \dotsc, 0)$ is a solution, but then so is $x+u$, isn't it? But $x+u$ as all odd coordinates.
Answer: I'm not sure what exactly are you asking for, but I observed the following properties.

I'm assuming you want solutions for $(x_1,\dots,x_n)$ given $y$. Let $z=y-x_1$, then $$3(x_2+x_3+x_4\dots+x_n)=4z$$
Hence, $z$ must be a multiple of $3$, so we write $3k=y-x_1\implies x_1=y-3k$ for $0\le k\le\left\lfloor\frac{y}{3}\right\rfloor$.

If $x_1=y-3k$ for some $0\le k\le\left\lfloor\frac{y}{3}\right\rfloor$, then $x_2,\dots,x_n$ are a solution  $\iff\sum_{i=2}^n x_i = 4k$.

Now to get all solutions, simply iterate all $k$, and for each, all $x_2,\dots,x_n$ s.t. $\sum_{i=2}^n x_i = 4k$.
That is, you can generate a solution form some other in two ways ("one two-case operation"):

(We redistribute the sum condition:) You can decrease (increase) some component $x_i,i\ge 2$ by $1$ as long as you increase (decrease) some other component $x_{j},j\ge 2$.
(We change the case of $k$:) You can decrease (increase) $x_1$ by $3$, as long as you increase (decrease) up to four other components $x_i,x_j,x_t,x_l$ for $2\le i \le j \le t \le l$ by $1$.

The set of all solutions is closed relative to this "two-case operation", so by repeating these two cases on any solution and all subsequently generated solutions, you can eventually reach all solutions.


doubt with the proposition used

Question: Is there any correction required for this sentence, She's waiting for people to respond by the invitations they sent out, is by the right preposition to use, if not then why ? and why can we use ** to instead of by ** ??
Comment: Hi Sandra. It is a matter of the verb. You *wait* (for people) **to** + Verb. He waited for his friends to arrive. She waited for the traffic light to turn green. If that is the extent of your question, then it is better asked on [English Language Learners](https://ell.stackexchange.com/).
Answer: I advocate the use of 'to' in this regard:
Check Cambridge Advanced Learners it is a great dictionary that highlights the correct use of prepositions. I tend to believe that it's the only dictionary that has the various uses of prepositions highlighted in the examples.
Examples
I want to respond to something that Norman said.
He responded by marching off and slamming the door behind him.
As you can see, by is used to refer to the subject that responds rather than the recipient/receiver.

doubt with the proposition used


Programmatically rename an XCode project

Question: I know one can rename a project by slowly double clicking the project name but I was wondering if it's possible to automate that through the command line (any language, possibly Apple Script) ?
Answer: Renaming an Xcode4 project is quite easy.
Click on Show the Project Manager to see the top level project file on the left side.
Click on the project name (here DeeTeeSaver will be changed to DeeTeeSaver2) in order to edit it and enter the new name.

It takes a second to let Xcode4 find out which parts have to be changed.
It then displays a dialog which parts will be changed. Simply click on Rename.
That´s it. No need to fondle around with AppleScript.
You might miss important parts inside the bundle.
Greetings from Switzerland, Ronald Hofmann
Answer: You will have to manipulate the .xcodeproj file, which is in XML format.
In my build process I have placeholder names that I simply search & replace with a command line app. If you need a generic solution you will have to parse the XML format (which is undocumented but not that hard to grasp).


RAM Row and Column Decoders

Question: I keep seeing similar diagrams of RAM like this abstract picture of a simplified RAM Layout. So I just arbitrarily selected this picture but my question is about this layout in general. My understanding is that the whole selected row sends their memory contents down their column lines and the column decoder selects the appropriate one to output. So is this understanding correct? And is the Row Decoder implemented by a decoder-like a 3 to 8 decoder- and is the Column Decoder a multiplexer? And are each of the column lines a bus? Is this how most RAM works in the big picture, for both SRAM and DRAM?
Comment: Yes and no.  I believe that some SRAMs may have different organizations.  Certainly the DRAM organization is as you surmise.  This is, to some extent, where burst mode comes from -- the read operation on a row takes time, but shuffling the right bit out of the column decoder is quick.  Even the earliest DRAM would let you do a read on a row, then read different columns within that row without re-doing the row operation.
Answer: Your understanding is basically correct.
The row address decoders are not implemented like a regular decoder; the layout of such a decoder would not be very efficient. Instead each row has a decoder that is basically a dynamic NOR gate. It consists on \$N\$ NMOS transistors in parallel, where \$N\$ is the number of address lines to be decoded. The true and complement value of each address line is routed over the top of the decoders...vertically, as your graphic is drawn. Since a NOR is also a NOT-AND we can selectively connect the gate of each NMOS transistor to either the true or complement of one address bit. The output of the decoder is where the NMOS drains connect together, and this is precharged before an access.
The column decoder is a selector...it selects a subset of all of the column lines. The column lines, or bit lines are single bits, not buses.
This is the general architecture for any kind of memory device. We like to make the core, the 2D Storage Array, have a relatively square shape. This is because the RC delay of the word lines and bit lines is proportional to the square of their length, so we don't want either of these lines to be really long.
Comment: Since the column lines are single bits, then is it just bits being stored in this 2d storage array? Do you use 8 of these 2d storage arrays to store a byte? What do you mean by column decoder selecting a subset? Sorry I've only taken a basic digital logic course so I'm not understanding a lot of this. Maybe it's beyond my current reach.
Comment: It is just bits being stored, but the storage array may be 64 or 128 bits wide...so there are 64 or 128 column lines. If you just want one byte out of the memory then the selector must choose which of the column lines you care about, based on some of the address bits provided.

RAM Row and Column Decoders


Is the Windows Live Connect Client ID a secret?

Question: I've just started Windows Phone app development. I'm using the Live Connect API and I am confused about the credentials. When I configured my app in the Live Connect Developer Centre I was given a ClientID and a Secret. However I don't seem to have to use the secret in my app, but I can only regenerate the secret and MS says "For security purposes, don't share your client secret with anyone." What's to stop someone who has the ClientID spoofing my app?
Answer: Yes, ClientID is not taken as a secret. Nothing serious can be done only with Client ID.
The Secret is required in important scenarios, like when you received a Windows Live authorization token, then you want to use it to get other tokens in order to access the users' OneDrive storage, you need submit your Secret together with your ID to the Live Server.(this is the Live Connect authorization flow)
Please read this article


How could I choose cost function in Qiskit TwoLayerQNN?

Question: So here is the problem, I've found that in a TwoLayerQNN, the backward gradient is only to minimize the expectation of observable I've chosen. But I'm not going to minimize the predict of the input, instead, I need to minimize the cost function. So how can I choose my own cost function without using NeuralNetworkClassifier? thanks.
Answer: Quantum neural networks in Qiskit Machine Learning do not store weights, they only provide a framework for computations of forward and backward passes. They are not aware of any algorithms that can be applied on top of them. Thus, they are not aware of any optimization processes. So, they don't have any references to loss/cost functions. While algorithms, like the above mentioned NeuralNetworkClassifer, and everything in the qiskit_machine_learning.algorithms represent trainable models, so they know what to optimize and how to do this. If you need a custom cost function, so you should consider one of the algorithms.


Are the pop-ups in 2010 enforced?

Question: I'm not a fan of the popup list add/edit dialogs to add content in 2010, is there an alternative UI, or is this something I have to get used to?
Answer: The only scenario which gives the option of an alternative UI is the case where the sites were upgraded from WSS 3.0/SharePoint 2007, and you make use of the Visual Upgrade capability. This allows you to preserve the earlier look and feel to allow you to transition more slowly e.g. to give time to make any required changes to custom master pages.
However it is meant only as a transition aid - you technically could stay in that mode forever, but users would be missing out on functionality exposed in the new UI e.g. async page refreshes when working with items in a list.
So you're going to have to get used to it, but as well as having much fewer postbacks/page reloads (as mentioned), the new UI brings other benefits. Most folks feel the "popups" are an improvement as you stay in context for what you were doing (and return to the 'greyed out' page once the dialog has closed). In SharePoint 2007 you frequently had to 'navigate back' which wasn't the slickest user experience. The ribbon (very contextual), status bar and notification area are other UI improvements.
P.S. They're technically not popups anyway, it's an IFrame loaded into the current page :)
Comment: I just came across this old post, the answer is incorrect as each list has an option to open the add/edit forms either in a dialog or in a separate page.
Answer: I am late to the party, but here you go:
under list settings, advanced settings:
Launch forms in a dialog? => select Yes or No
Comment: I find this setting, while looks promising, does not always work for some reason. http://sharepoint.stackexchange.com/questions/64750/disabling-the-dialog-pop-up-for-calendar-views

Are the pop-ups in 2010 enforced?


What does it mean to check behind?

Question: In poker terminology, there's something called "checking behind". What does this mean?
Comment: If you are interested in Poker please commit to the new [Poker SE Currently on Area 51](http://area51.stackexchange.com/proposals/3425/poker?referrer=AGKNzHVrmSTgMMEpzVsZAg2)
Comment: I'm already commited there :)
Answer: It's when you 'check' (choose not to bet anything) after all players before you have checked.  Often with a good hand you'll want to do this to give your opponent(s) an opportunity to improve and be willing to bet.  With a weak hand you might want to do this if you suspect your opponent is slow-playing a good hand for the same reason.
Comment: With an un-beatable hand it is a good idea to check behind, and let someone catch up.  Otherwise, you want to make bets which make it a mistake for them to attempt to draw out - because more often than you want, they will draw out.
Comment: Mostly good advice for a normal situation in a cash game.  However, like nearly all advice on poker strategy, it depends.  There are other factors that affect this decision, so don't take this as a hard and fast rule.  This is why I said 'often' in the answer above.
Answer: Checking behind is when you are last to act, and you check.
Comment: The other answer says that it is checking behind when all players before you have checked.  If there is someone behind you still to act, that is not (what I know as) checking behind.
Comment: Is this identical to the other answer?  If you, it'd be better to vote it up instead of answering yourself.  If not, please expand upon the differences so that voters can make an informed choice.  Thanks!
Comment: According to http://www.pokerstrategy.com/glossary/Check-Behind/, @ChrisMarasti-Georg is right - it's only a check-behind if you're last to act.
Comment: It is a real advantage to check (bet, or raise) "behind," (after everyone else has acted) which is why you can play weaker cards than usual on the "button," or "last" position.

What does it mean to check behind?


Is there a 32-bit version of Floating Sandbox?

Question: Floating Sandbox is a PC game where you have all these tools and can destroy a ship, and I want to play it, but there is one problem. I have 32-bit Windows 7, but I only know of downloads for the 64-bit version. I want to know if there is a 32-bit version or a way to make the 64-bit version compatible with 32-bit Windows 7.
Answer: As this is an Indie project, and only released only a couple of months ago, if they intended there to be a 32-bit version, it has not yet been released, and would still be working on it.
However, there's no way to tell without talking to them directly about it.
And unfortunately, there is no tool that can allow you to run this in a 32-bit environment; without hacking up the program in some way itself.
Answer: Unfortunately there is no 32-bit version at this moment. The game is a physics simulation and it's quite hungry for CPU resources; for this reason, the source code tries to take advantage of all possible performance improvements available on modern low-end CPUs, such as SSE vectorization and data packed in 64-bit words.
Building the game for 32-bit platforms not only would require considerable effort on our side, but it would also not yield a satisfying user experience - the simulation would very likely lag to the point of being unusable.


2002 santa fe problems please help

Question: Hey i have a 2002 Santa Fe and while i was driving the cars lights went dim then radio turned off. The car started to jolt and its not the first time this has its done it but i have checked the alternator and got a new battery for it but now the car wont even start like at all any suggestions. Please help. i have been having the same problems for a while but it is not an everyday thing its moor like every few weeks.
Answer: I would suggest that you need to check all the electrical connections and cables / wires as something seems to be loose or broken.
It may be relatively easy like a battery cable or difficult to find like a loose internal link in the fuse box (which can get moved when a door is slammed for example).
Finding this type of problem can make looking for a needle in a haystack easy!...
Comment: Check for signs of rodents/creatures nesting in, around, and under, the engine bay, any signs of damaged wiring etc. Remove the grounds, clean them, and tighten. Look for puddling and/or staining on/around electrical connectors.

2002 santa fe problems please help


Which amendment does this violate?

Question: Bob requests a lawyer to be present while the police interview him after being arrested. The police just laugh.
Comment: What amendment of what? Which constitution? Where are you from? This is an international site you know.
Comment: To illustrate why the where and when is relevant: It wouldn't violate any rights to deny you the lawyer in Ukraine at a specific point in 2014: the police were completely disbanded and only re-created by an act minutes later, and many policemen did not transition from the old to the new police - in that short timeframe there was not a single person that legally had Police powers. If they arrested you just before that point, and then, as you asked for the lawyer looked at the watch, laughed and left the room, they just lost their job and walked away. (I am sure nothing like that happened)
Answer: The Sixth Amendment to the US Constitution guarantees assistance of counsel for the accused in all criminal prosecutions. The Fifth Amendment protects a person from being forced to self-incriminate. Taken together, in Miranda v. Arizona, the Supreme Court interpreted this to mean that police cannot continue interrogation after you have requested an attorney. Laughter is actually not a violation of your rights, the violation would come from continuing to interrogate you, or in prohibiting you from contacting your attorney or not providing an attorney if you cannot afford one (via the public defender's office).
Answer: In the United States, this does not violate Bob's constitutional rights.
If the police stop laughing and start asking Bob questions or otherwise attempting to elicit information from him, that would violate Bob's Sixth Amendment right to the assistance of counsel.
Comment: @RossPresser Continuing to laugh for hours does not violate any right, nor does leaving without contacting an attorney. The Sixth Amendment right to counsel allows you to have an attorney with you while the police question you; it does not give you the right to have an attorney with you at any given moment in any given location. Unless the police are seeking your cooperation in their investigation, you generally don't have the right to have counsel with you. (Also, the above comment about the habeas corpus right is wildly incorrect.)
Comment: Pardon for being ridiculous, but what if they continued to laugh for hours? Or perhaps less ridiculous, what if they stopped interrogation but simply left him alone, not attempting to contact an attorney?
Comment: @RossPresser Do you mean imprisoning Bob for an excessively long time (like 1 year for speeding and hitting nobody)? This would violate Bob's [habeas corpus right](https://en.wikipedia.org/wiki/Habeas_corpus).

Which amendment does this violate?


How can some statements be consistent with intuitionistic logic but not classical logic, when intuitionistic logic proves not not LEM?

Question: I've heard that some axioms, such as "all functions are continuous" or "all functions are computable", are compatible with intuitionistic type theories but not their classical equivalents. But if they aren't compatible with LEM, shouldn't that mean they prove not LEM? But not LEM means not (A or not A) which in particular implies not A - but that implies (A or not A). What's gone wrong here?
Comment: "All functions are continuous" results from what are classically regarded as discontinuous functions not being accepted as being functions in intuitionist type theories as they cannot be computed to arbitrary accuracy for some numbers known to arbitrary accuracy. An example could be the sign function $\text{sgn}(x)$ when $x$ is close to zero but whether $x$ is above or below zero is not known: $\text{sgn}(x)$ does not become continuous in intuitionist type theories but instead stops being a function.
Comment: Not LEM doesn't mean $\lnot(A \vee \lnot A)$. $A \rightarrow (A \vee \lnot A)$ is true even in (counter)intuitionistic logic. Not LEM means that $A \vee \lnot A$ is not a tautology, so there are - or at least may be - propositions that are neither true nor false [but it may be that "true" means provable and "false" refutable in intuitionistic logic, and that there are propositions that are neither provable nor refutable is true also in classical logic].
Comment: I don't think that solves the problem. A finite proof a contradiction from "all functions are continuous" + LEM should involve a finite sequence $A_1 \lor \lnot A_1 ... A_n \lor \lnot A_n$ of applications of LEM. Consider the first $m \leq n$ such that "all functions are continuous" + $A_1 \lor \lnot A_1 ... A_m \lor \lnot A_m$ is inconsistent. Then "all functions are continuous" + $A_1 \lor \lnot A_1 ... A_{m-1} \lor \lnot A_{m-1}$ refutes $A_m \lor \lnot A_m$, which is absurd.
Comment: @user61295: that would not be absurd at all. Since you are already starting with an inconsistent set of assumptions, if you remove one the remainder will always prove its negation in classical logic.
Comment: I added the "logic" tag; the other ones have very few followers.
Answer: If $A$ is a sentence (ie has no free variables), then your reasoning is correct and in fact $\neg (A \vee \neg A)$ is not consistent with intuitionistic logic.
However, all the instances of excluded middle that are contradicted by the statements "all functions are continuous" and "all functions are computable" are for formulas of the form $A(x)$ where $x$ is a free variable. To give an explicit example, working over Heyting arithmetic (HA), let $A(n)$ be the statement that the $n$th Turing machine halts on input $n$. Then, it is consistent with HA that $\forall n\;A(n) \vee \neg A(n)$ is false. That is, $\neg (\forall n \; A(n) \vee \neg A(n))$ is consistent with HA, and is in fact implied by $\mathsf{CT}_0$ (essentially the statement that all functions are computable). Note that even in classical logic this doesn't directly imply $\neg A(n)$, which would be equivalent to $\forall n \; \neg A(n)$. What we could do in classical logic is deduce $\exists n \; \neg (A(n) \vee \neg A(n))$ and continue as before, but this does not work in intuitionistic logic.
Answer: This is an expansion of Henry's comment. If we don't add any additional axioms, intuitionistic logic (by which I mean all the standard systems such as HA, IZF, etc.) is compatible with the law of the excluded middle LEM, but does not prove LEM. This is a useful fact to know when learning about these logics - they don't prove anything that is classically false, although there are some things that are classically provable that they cannot prove.
Now, if there is a sentence $\lnot \phi$ that is classically provable but not provable in some intuitionistic system $I$, then $\phi$ is classically disprovable, so $\lnot \phi$ has no classical model. But since $\lnot \phi$ is not provable in $I$, $\phi$ is consistent with $I$ (because a proof of a contradiction from $\phi$ is exactly a proof of $\lnot \phi$ in an intuitionistic system). So by the appropriate completeness theorem for $I$, there will be a model of $I$ satisfying $\phi$, but that model must necessarily be nonclassical.
Concrete examples of $\phi$ that have this property are "every function from $\mathbb{N}$ to $\mathbb{N}$ is computable" and "every function from $\mathbb{R}$ to $\mathbb{R}$ is continuous". These are disprovable classically, but not intuitionistically. How is that? The way to understand it is to exame the classical disproof.
To prove "not every function from $\mathbb{N}$ to $\mathbb{N}$ is computable" we would say to define a function $f$ so that, for each $n$, if the $n$th computable function halts with output $m$ on input $n$ then $f(n) = m+1$, and $f(n) = 0$ otherwise. Then it is immediate that $f$ is not computable. In intuitionistic logic, if there was an $f$ with the property, we could still prove it is not computable. But the definition just given is not a sound definition in intuitionistic logic. It is possible to show for many intuitionistic systems that they do not prove "for all $n$, the $n$th computable function either halts on input $n$ or does not halt on input $n$". So the definition of $f$ by cases fails, because we cannot prove that the cases in the definition are exhaustive. The problem is not that $f$ is not a functional relation, it's that $f$ may not be a total function if we interpret the definition in a nonclassical model.
Similarly, the easiest way to make a discontinuous function on the reals is to define it by cases, e.g. $g(0) = 1$ and $g(x) = 2$ for $x \not = 0$. We cannot prove intuitionistically that there is no function $g$ with that property, because there are classical models of intuitionstic systems where there is such a function. But the definition by cases is only successful in models that satisfy $(\forall x\in\mathbb{R})[x = 0 \lor x \not = 0]$, and it turns out there are nonclassical models of intuitionistic systems that do not satisfy that sentence. In such models, we cannot define the function $g$, in fact.
Answer: I think you're confusing two things here: intuitionistic logic and finitistic (intuitionistic) mathematics. Intuitionists are driven by the philosophy that Truth should be equated with provability and Falsehood should be equated with refutability.  Hence, intuitionistic logic is characterized by rejecting several classical tautologies such as LEM (because there may be statements which are neither provable nor refutable), Double Negation Elimination (to refute that a proposition is refutable doesn't prove it is provable), or $\neg \forall xP(x) \leftrightarrow \exists x \neg P(x)$ (because for the intuitionists an existence proof must be constructive). Note, however, that this doesn't commit the intuitionist to claiming that there is a counterexample to LEM, i.e. just because LEM may not always be 'true' (provable) doesn't mean there is (we can construct) a counterexample.  Finitistic mathematics on the other hand is characterized by the rejection of a 'completed' infinity. It only acknowledges (possibly infinite) objects that can be computed to arbitrary precision. So in a sense finitistic mathematics rejects non-recursive sets and proofs involving diagonal arguments: For example Cantor's proof that $\Bbb R$ is uncountable is not acceptable in finitistic mathematics, because it implements a construction of an element by 'infinite inspection' (by complete inspection of an infinite list). In finitistic mathematics "all real functions are continuous" is true because $\Bbb R$ only consists of the constructible elements, which are countable, and for any countable set of pairs (x,y) there is a continuous map with $f(x)=y$. Now intuitionistic logic doesn't imply finitistic mathematics, nor is it refuted by classical logic, but it usually comes with the philosophy that grounds intuitionistic logic.
Comment: One can equate truth with provability even in classical logic (e.g. formalism), so that on its own doesn't give a good explanation of why constructivists might reject LEM. After all, something proven with the aid of LEM is still proven...


What are Target rules in Magento EE?

Question: I want to understand the Enterprise Edition catalog target rules and What are additional features of target rule module over the CE Catalog?
Answer: Customer Segmentation, Targeted Promotions & Merchandising
Segment customers into groups and optimize marketing initiatives by identifying specific customer
groups using specific characteristics (address, location, sex, etc.) and/or value (purchase history, on-site
browsing, etc.).
Advanced segmentation capabilities include the ability to identify unknown site visitors. Whether they're
new visitors or returning customers who have not logged in, you'll now be able to identify and target
them with special promotions to convert browsers into buyers.
Dynamic Rule Based Product Relations
Dynamically target customers to present up-sells, cross-sells, and related products based on their
specific product selections. Rules are easily administered through a condition based tool, allowing
marketers to easily manage specific product suggestions, shopping cart price rules and banners
to any customer segment to encourage additional purchases.
Please refer the Guide
Magento Features List

What are Target rules in Magento EE?


Why does Apple use this guideline "A label is often unnecessary when placeholder text is present"

Question: In which context does Apple use this guideline, and why did they do so? I can only see the logic in the context of having an input field where you search. It just seems a bit odd since it has so many negative consequences, sure it reduces clutter and shortens the length of the form but I think that does not make up for the consequences.
Answer: Here is the source for your quote.
You can split data entries into two kinds:

Fill and forget
Fill and persist

Fill and Forget

In this scenario:

The user lands upon some data entry interface
The form is empty
Once filled by the user there is an action to progress to the next "stage"
The data entered is not persisted - it only enables progressing to the next "stage"
Once submitted, the user cannot return to data entry interface (meaning there is no "previous" options, or no cyclic paths returning to that data entry in the user journey).

Gatekeepers are good examples for this data entries type. Examples:

Login forms
Captcha forms
2FA forms

And also:

Contact request form
Newsletter signup form

In these sort of cases, you could replace a label with a placeholder:

The form is empty to begin with
The place holder denotes the purpose of each field
Forms are generally short so either the nature of each field is in the user's memory (eg, username), or there is little need to edit previously entered values.
Once submitted there is no way back, so no issue with no labels or placeholders (due to the filled form).

Fill and Persist

Unlike the previous kind, once filled data is persisted and users can return to these data entry interfaces for editing purposes.
Examples are "delivery address" in a checkout wizard.
Here, it makes sense to put label or users will not be able to infer the nature of each field. (Users can infer from the values, but this is error-prone).
Comment: I see thanks for the clarification. However, why do they emphasize and write "often" I can't find any good examples besides the one I gave.
Comment: I'm not sure. A proper cognitive and contextual analysis could lead to the use of placeholders even when not immediately obvious. But I'd argue that more often than not data entries can be re-visited so placeholders won't be an optimal solution.
Comment: Alright, thanks.
Comment: Just to add on, I believe that Apple's guidelines on the preference of placeholder text over labels is to encourage designers to reduce the amount of user memory needed when designing forms in general. Forms should be simple to fill, convenient and effortless in exerting memory recall by users.


is there an allowability to gamble/bet

Question: I heard from a Rav that you are allowed to gamble/bet if it is not for your livelihood. How accurate is this? I heard the reason why you would not be allowed to is because it can be theft. Please provide sources if possible.
Answer: There are 2 possible reasons given for the prohibition of gambling (both of which you mentioned in your question): a poor livelihood choice (yoshvei kranot) and theft due to a lack of a true legal contract / intention to give up the funds on the part of the loser (asmachta; i.e. everyone gambles because they think they will win and don't really have in mind that they will lose with sufficient legal intent to legitimize taking their money when they do lose).
See: http://etzahaim.org/index.php?option=com_content&task=view&id=39&Itemid=29

The Gemara bring down a debate about why a dice-player's activity disqualifies him:
Rami Bar Hama says that the dice player is disqualified because the
  wager agreement he is entering into is an example of asmachta4,
  because each player consents to the terms of the game only because he
  expects to win. Since the loser does not willingly surrender the
  wagered amount, the winner is considered to be stealing when he
  collects, and is thus ineligible as a witness or judge.5
Rabbi Sheshet says this agreement is not considered an asmachta.
  According to this opinion the only situations that involve asmachta
  are when the individual relies on his own ability. Dice players
  realize that the outcome of the game is determined by chance and not
  their own personal skill6. Rather, dice players are disqualified
  because they are not involved with furthering the general welfare of
  society.
The Talmud explains that the difference between these two opinions is
  the case where the gambler learned another profession.
Rami bar Hama would still disqualify the gambler by virtue of his
  accepting winnings based on a non-binding asmachta agreement, whereas
  according to Rav Sheshet he is eligible because his second occupation
  is socially useful.7
According to Rami bar Hama the prohibition involved in gambling is not
  the gambling itself but taking the winnings which involves the 'dust
  of robbery'.
According to Rav Sheshet there is no prohibition in taking the
  winnings, the problem is being a gambler. This occupation is
  distasteful as is non productive.
Tosaphot and the Mordechai explain that even according to the above mentioned opinion which permits "Dice Playing" as long as one has
  another profession, it is only permitted to do so if the actual cash
  is placed on the table and the money is transferred to the winner
  immediately follwing his victory. If, however, there is no immediate
  cash transaction but rather the game is based on Amanah, trust that
  the loser will pay, then even according to the more lenient viewpoint
  this is considered asmachta. There are those opinions that add that
  even when the cash is placed on the table, the table must be jointly
  owned by all players. Elsewhere18 the Mordechai further restricts the
  aforementioned leniency, by distinguishing between gambling that
  involves some form of skill and those that involve none. Only gambling
  that involves no skill is permitted according to this lenient opinion.
  The Shulhan Arukh follows the opinion of Rambam by classifying gambling as asmachta which would mean that the winner is not entitled
  to the proceeds of his victory and retaining would be considered
  stealing.22 However, like Rambam, he also only disqualifies the
  gambler as a witness if gambling is his only means of livelyhood,23
  thereby creating the same compromise between Rab Sheshat and Rami Bar
  Hama as did Rambam. The Remah however disagrees with the Shulhan Arukh
  and decides the law according to the Tosaphot and Mordechai.
Comment: Very interesting. It would seem that according to all parties playing the lottery while holding down a job doesn't count as gambling. You still have a valid occupation (yoshvei kranot) and there is no wager agreement to enter into with an asmachta - it's a straightforward *a priori* purchase of the ticket. Since all funds are transferred before the lottery itself, it avoids the avak gezel problem, and "lottery player" isn't an occupation in this scenario.
Comment: Raffles are allowed because when you buy a ticket your intention is primarily to give the money to the Tzedaka and you don't expect to win the prize, and if you don't you're happy your money went to tzedaka anyway
Comment: What about playing poker?
Comment: "Elsewhere the Mordechai further restricts the aforementioned leniency, by distinguishing between gambling that involves some form of skill and those that involve none. Only gambling that involves no skill is permitted according to this lenient opinion." - Poker generally involves some skill so there's presumably an increased likelihood people will convince themselves that they know they'll win...

is there an allowability to gamble/bet


Choosing PhD advisor between Professor X and an Assistant professor Y who was a PhD student of the professor X

Question: I got accepted in two different US schools for CS PhD programs. My prospective advisor/supervisor for the two schools are Professor X and Professor Y respectively. Professor Y was a PhD student of Professor X. Professor X has a lot of successful PhD students coming out of his lab and he is a heavyweight in the field. Professor Y is a tenure-track assistant professor but has really good recent A* publications. How should I approach this issue of choosing one of them?
Answer: (Moving from comment to answer)
This may not be true everywhere, but when faced with a similar decision I was told that the more established professor is more familiar with the department politics and how to get students graduated. Graduation should be a top priority, and if Professor X has a good track record of graduating students, that may be the best choice. Professor X also may have heavily influenced Professor Y's work, so it is unclear how Professor Y will work without Professor X's supervision.
Answer: Let me suggest that Professor X is probably safest, other things being equal. There is a danger in having untenured professors, like Y, as an advisor since their first priority is to earn their tenure and it can easily get in the way of properly advising students. You won't contribute much to their tenure, and so they need to focus on their own work.
Not every such situation is bad, but it is better to have someone who has the flexibility to help you succeed without the weight of an important career point looming. And if, for some reason, an untenured advisor fails to earn tenure, either during or after your studies it will cause issues for you.
I once had an untenured prof as advisor and found exactly this problem. I was far down the list of his priorities.
Inexperience can also be an issue in some cases.
Comment: How exactly a professor get tenured? Isn't it directly related to number of successful graduate students his lab produces? I don't understand how advising students could get into the way in their tenure? What you mean by their own work?
Thanks a lot for the answer Dr. @Buffy
Comment: The biggest factor, in most research universities, is the number of publications (first author, sole author). Everything else has lesser weight. If they "get behind" in production, their students can suffer from lack of attention. It isn't an absolute, but the forces push in that direction.
Comment: In my field the only way to get tenure is by publishing papers with your grad students (there's no one else to do the research...). This is typical for the natural sciences in North America. I think mathematics might be a special case that is different in that regard (I don't know where CS falls).


How to reference one foreign key column with multiple primary key column

Question: I am creating BOOK_Issue table which will contain id of person to whom the book is issued.
i have a column name user_id witch will contain ids from tbl_student as well as tbl_faculty. so how to set user_id field of book_issue table with reference to two primary key columns.
Answer: Your database schema is not correct.
If you expect unique IDs then they should be in one table.
You can create a table with all the users, and have a column to set their type (student, faculty). Then create 2 different tables for each type that has the proper information for each user based on their type.
Answer: Create a "person" superclass that can be either of type "student" or type "faculty". Reference this from the BOOK_Issue table instead.
Basically to create this relationship, you'll need one unique ID that spans both "student" and "faculty". Put this in a table (tbl_person?) and have each row in tbl_student and tbl_faculty reference this new table. It's probably also best to then pull out the fields present in both tbl_student and tbl_faculty and put them in this new supertable instead.
Answer: You can solve the problem by either having an extra column in BOOK_Issue table, next to user_id, which indicates if this is a Student ID or a Faculty ID.
Alternatively, the IDs themselves may readily include some pattern which indicate their nature (for example no all faculty Ids may start with say "UC", and none of the student Id are so).
The two solutions above then allow using queries similar to the following
SELECT B.*,
       CASE B.BorrowerType  -- could be LEFT(user_id, 2) etc...
          WHEN 'S' THEN S.Name
          WHEN 'F' Then F.Name
       END As Name,
       CASE B.BorrowerType
          WHEN 'S' THEN S.PhoneNumber
          WHEN 'F' Then F.Phone    -- Note that these constructs allow
                                   -- mapping distinct columns names etc.
       END As PhoneNr
FROM BOOK_Issue B
LEFT JOIN tbl_student S ON B.BorrowerType = 'S' AND B.user_id = S.id
LEFT JOIN tbl_faculty F ON B.BorrowerType = 'F' AND B.user_id = F.id
WHERE B.DueDate  < '11/23/2009' -- or some other condition

This can get a bit heavy when we need to get multiple columns from the student/faculty tables.  A possible alternative is a UNION, but this would then cause the repeating of the search clause.
Finally, the best solution but not avaible on all DBMS is a sub-query driven by an "IF B.BorrowerType = 'S' " condition.
Answer: This should be your table design:
FacultyTable (FacultyID, FacultyName)
StudentsTable (StudentID, StudentName, FacultlyID, ...)
BookTable (BookID, BookName, ...)
UsersTable(UserID, UserName, UserPassword, StudentID, LastLogin, ...)
Now this is the main thing:
BookIssedTable(BookIssedID, BookID, UserID)
//This table tells me that a book of "BookID was issued to a user of "UserID"
//this can be better for this is certainly a great improvement from the initial design.


How to index full size images but return thumbnails in Google Image Search?

Question: Many website owners use Google Image Search to download images from my website to use on their own website. I want to return a thumbnail image when clicking "open image in new tab" from Google Image Search, so they can't steal the full size image. I have already disabled right click on the website, but now they are using Google Search.
Answer: To answer your question as written, you can prevent users from getting to your full-size image directly from Google Image Search by opting out of Google Image Search's inline linking.
From Google support:

Opt out of Google Images inline linking
If you choose, you can prevent the full-sized image from appearing in the Google Images search results page by opting out of inline linking in Google Images search results.
To opt out of inline linking:

When your image is requested, examine the HTTP referrer header in the request.
If the request is coming from a Google domain, reply with a 200 HTTP status code, or a 204 HTTP status code and no content.

Google will still crawl your page and see the image, but will display a thumbnail image generated at crawl time in search results. This opt-out is possible at any time, and doesn't require re-processing of a website's images. This behavior isn't considered image cloaking and won't result in manual actions.

However, it's important to note that while this will act as an additional deterrent, nothing can truly stop determined users from copying your images. Users with technical knowledge will always be able to circumvent image copy protection. They could use a browser extension to defeat your anti-right click code, use their browser's developer tooling to directly save the image out of the HTTP response, or simply take a screenshot of their computer screen and crop your image out of the screenshot.
If you own the copyright to the images you are trying to protect, then using DMCA takedown requests may be a more viable option than any technical countermeasure. They are easy to draft and send, and can legally force the hand of the offending users' hosting provider.
In any case, I would consider clearly marking the images on your site with their copyright information. Though not strictly required to establish copyright in the USA, it may be required to establish copyright in other countries, and doing so affirms your ownership of the images while implying that they cannot be reused without permission.
Though heavy-handed, it may also be an option to watermark the images.


Is Dasein Heideggerian Zen?

Question: I was reading about Heidegger's concept of "Dasein" as being or existing in the moment. It struck a chord of similarity with the eastern concept of Zen. Is there a parallel?
Comment: In general, I would say "no", but it'd really help to have a quote of where you think Heidegger uses Dasein in this way (specifically there's no immediate "in the moment" connotation to the German term Dasein -- which means "existence" in Hegel for instance). Also, how are you defining Zen?
Comment: Sorry -- the definition i read was `"being there"/"existence"` which I (mis?)interpreted as as an emphasis on being/existing it the moment.
Comment: Maybe they are parallel, but pointing in opposite directions?  Zen is a desired state of simplicity.  Dasein is not a desired state, nor is it ever simple.  It is the position one is thrown into when one does not focus away from oneself and abstract away the complexity of one's composite self into something with an identifiable purpose.  Parts of ourselves are ready-to-hand, but the whole of us denies all readiness-to-hand and leaves us in a place that most of us find rather dark.
Comment: why is this being closed as "unclear", is the pharse "what parallels" forbidden? whoever is voting to close all these questions is struggling imho
Comment: "Zen" derives from "meditation", and Dasein is "being there" so the words are not counterparts. The commonalities between the outlooks, however,  are well-known and analyzed in detail e.g. in [Storey's Zen in Heidegger's Way](http://www.cpp.edu/~jet/Documents/JET/Jet5/Storey113-137.pdf), who identifies three major ones:"*Zen  is uncompromisingly non-metaphysical; 2) its discourse is poetic and non-rational; and 3) it aims to provoke a  radical  transformation  in  the  individual, not  to  provide  a  theoretical  proof  or demonstration of theses about the mind and/or the world*".
Comment: Put on hold......the question is very clear to me....
Comment: Interesting +1. But for me too unknowledgeable to answer.
Comment: And the question Virmaior is asking >>Also, how are you defining Zen? would probably first come.
Comment: >  **it aims to provoke a radical transformation in the individual, not to provide a theoretical proof or demonstration of theses about the mind and/or the world"** Can't agree more than that. If you have gone to anywhere where Zen is practiced and you have experienced, Zen's aim is, may be, has **almost** "nothing to do" with the **nothingness**.
Answer: Dasein
No, Dasein does not mean 'being in the moment', but means

Dieses Seiende, das wir selbst je sind und das unter anderem die
Seinsmöglichkeit des Fragens hat, fassen wir terminologisch als
Dasein. (Sein und Zeit, §2)
(This entity which each of us is himself and which includes
inquiring as one of the possibilities of its Being, we shall denote by
the term "Dasein")

Simply put, it is Heidegger's formal name for the human being.
Zen on the other hand is the name of a form of Buddhism, or the meditation this form practises.
Paralells between Zen and Heidegger
However, there have been quite many studies and essays on the parallels between Heidegger and Zen. And Heidegger had some Japanese students who where Zen practitioners/scholars (e.g. Nishitani, Tanabe). For example, the present time for authentic Dasein is called 'Augenblick' (moment, instant), which some have interpreted as meaning 'being in the moment'.
Difference between Zen and Heidegger
The overall approach of Heidegger and Zen is nevertheless quite different. Heidegger wants to renew and (re)ask the question of Being. The essence of a human being is for him thinking. He focuses on philosophy and poetry.
Zen, so it seems to me (but I'm no expert), is about realizing the buddha nature, the emptiness of all, satori, etc. This realization is by letting go of thinking and it is usually not in/via language, but by meditation practice, koans.
So, both the goal and method of Heidegger and of Zen seem quite different to me.
Comment: I am very afraid I would like to say, the concept you say "the emptiness of all" does not fit with the nature of "Satori".
Answer: I would like to submit this as an complement about Zen.
As Coinfold wrote at the comment line, but although, his citation , in which Taoism and Zen Buddhism is simultaneously analyzed is dangerous, in my opinion, the final summarization would be fine to me.
Western philosophers, it seems to me, favor to consider the "emptiness" in the eastern sense. If anyone has practiced Zen, then you eat, meditate, sleep regularly. If I take the "emptiness" literally, I may have to go more to Sokushinbutsu, in which "practitioners" cut meat, even cereals, and as is in the link,

The monks would slowly reduce then stop liquid intake, thus dehydrating the body and shrinking all organs.

To attain to the height or same being of Buddha.
Now, why was Zen practiced in the middle age Japan?
Because, they at the time, faced constant death. The then "sovereignty"
Ashikaga Shogunate was very weak, battle was conducted yearly basis every
where, ( please note, Ashikaga Shogunate was not able to issue its own currency
due to the lack of power ), thus people felt "諸業無常" ( English translation ), in which they say worldly things are not permanent, changes the form constantly, ( even after the death ), and I think Zen's emptiness, if you would like to prefer to emphasize, is more close to that idea. And through or after realizing such emptiness, as Coinfold says, in a way very radically, Zen's final destination is the "transformation of the self". But I am afraid I can not agree Zen is "non-metaphysical". It's metaphysical in a sense that their aim is to become closer to closer to Satori, aka Buddha's final realization. To me, the most closest idea is that of Engels, who also saw worldly things changes constantly and do not possess fixed position ( but in Western sense ), and If I try to answer to the OP's question, the answer would be No.
Answer: I have frequently noticed a Buddhist influence in Heidegger's philosophy.  A poignant case is Zen's focus on 'nothing', also aligning with aspects of negative theology, for example Meister Eckhard's philosophy, about which Heidegger writes

we find a remarkable parallel to the Hegelian determination of being
  and its identification with nothing. The mysticism of the Middle Ages
  or, more precisely, its mystical theology is not mystical in our sense
  and in the bad sense; rather, it can be conceived in a completely
  eminent sense.

Some Traditional Theses about Being
Answer:
Many commentators have remarked on the affinities between Heidegger's
  thought and East Asian traditions such as Vedanta, Mahayana
  Buddhism, and Taoism

There's a lot of google hits for Heidegger and Buddhism. Unfortunately, I have only read a monograph on Buddhism and Nietzsche, and material in general which merely mentions Heidegger in passing.
I would heisitantly say that it makes sense to say that Dasein is what experiences kensho, but then you may not find anyone who agrees with that.

Is Dasein Heideggerian Zen?


Nothing rendering on Windows server

Question: Not sure what happens but a site I'm running on a windows server displays nothing now. I can't get it into debug mode. Also, works perfectly fine locally on MAMP and on a linux set up with 1and1... any help would be amazing!
Comment: what happens if you set the debug to 1 in index.php ? I vowed never to use 1and1 again for EE hosting, let alone on a Windows server. Did you run the EE wizard before hand to make sure the server was compatible?
Comment: It's actually on gearhost and the ee wizard passes except for supporting url segments. The sight was working fine up until I pushed a round of changes yesterday night. Setting debug to 1 doesn't give me any data for some reason.
Comment: can't say I've heard of them to be honest. What changes did you make for it to stop working?
Comment: "Site was working fine up until I pushed a round of changes yesterday night" is a huge clue but your question contains no detail about the changes. With so few details in your question, it's pretty difficult to help.
Answer: According to Gearhost docs, you can set a PHP.INI file per site. Using these docs, you can override the default PHP.INI settings. Create a file which shows the output of the phpinfo function to see what your current settings are. It's possible that PHP is set to output errors to a log file and not to display them on screen. This makes sense for a production site.

Nothing rendering on Windows server


iPhone messages to iPhone number to manage account

Question: I followed directions on getting iPhone messages to iPad. When I clicked on receive only my email addresses showed up- my cell number not there
How do I add phone number. I have iPhone 6
Comment: Welcome to Ask Different. It would help us if you provided additional info, such as the types of devices, OS, etc.  Also let us know what you've already done to solve the problem yourself.  Please see [ask] for how to ask good questions that have a better chance at being answered.
Answer:
First thing to do, on your iPhone go to settings, then messages.
Look at the bottom where it says "send & receive" and select.
Now look to see which you have selected under the "you can be reached by iMessage at...does it show your phone number or an email address?
If it shows an email address, change it to your phone number.
Next, go back one screen (select messages, in top left corner).
Once there, look down to the middle where it says "Text Message Forwarding" and select.
Here you should see your iPad (and any other device you have attached on your Apple iCloud account) and turn the iPad on.
Close out of settings on your iPhone now.
Now go to your iPad settings and then Messages.
Check at the top to confirm that iMassage is turned on.
Next look halfway down where it says Send & Receive and select.
Now look to see what you have selected under the "you can be reached by iMessage at and make sure your phone number is selected.

That's it. If you don't see your iPad in step 7, then you haven't logged into it with your iCloud account (or at least not the same Apple ID as your iPhone)and will need to do so before proceeding.
Also, I have found it is easiest to use your iPhone phone number only and no email addresses, otherwise you can end up with two different conversations with the same person.


How can I make WorldEdit ignore water?

Question: Is there a way to like ignore water in WorldEdit? If you want to edit the terrain under deep water you will just edit the water instead.
I'm almost sure you can remove the water then edit the terrain then fill back to water but is that really the only choice?
I'm playing in Minecraft 1.16.1!
Answer: You can use the replace near command to replace one type of block at a time.

The only downside of this is that you have to run it multiple times.

How can I make WorldEdit ignore water?


I have a coolant leak, a big one, but my car isnt overheating... whats wrong?

Question: Okay, so i have a 2010 impala. Recently i had a very slow drip of coolant from my vehicle. It slowly started to worsen. I got a bottle of kseal and put that into my vehicle, it stopped the leak outta no where. That last 2-3 days. Now my vehicle is literally dripping coolant like a faucet that was left on. Im going through a bottle of coolant in a day. I had a mechanic friend look at it. They changed the water pump gasket because we thought that was the issue. As soon as it was turned on and revved a bit, it started leaking heavily again. So the gasket wasnt the issue. Theres zero coolant anywhere near the radiator. The hoses have no holes. But its leaking somewhere around my belt because its leaking onto my belt and causing the coolant to spread everywhere up under my hood and onto my fans. We looked at the water pump and theres nothing wrong there. Once the car is running and its dripping heavily, i took the radiator hose cap off and it stopped leaking, i put the cap back on and it started leaking heavily again... no one can figure out where its leaking from and my car has been taken apart and put back together several times for this specific reason and my car isnt overheating at all no matter how much coolant i lose. anyone have suggestions?
Comment: I'd personally have a look at the water pump itself. Most have a weep hole designed to drip coolant when the internal bearing goes bad. Everything you've said seems to indicate the pump to me. Near the belt, a leak that never overheats, drip that progressed to "faucet," etc. Honestly, there isn't much else in that area to leak from. Anyways, best of luck.
Comment: fill the coolant system and use air pressure to look for the leak with the engine off,be sure to have good lighting and get help from a friend to look for the leak.
Comment: All I can say is get a BETTER mechanic.  Coolant leaks are not that hard to find since you will see the evidence squirting out.  There are multiple possibilities but a good mechanic will diagnose the problem and fix it rather than just replacing stuff.
Comment: Some cars measure the engine temperature by measuring the coolant liquid temperature. If you remove all the coolant, it will get erroneous temperature readings that looks like the engine is cool, while at the same time the engine is overheating by the lack of the coolant liquid.
Answer: I had a similar problem and it was my intake manifold gasket.


Is the change of the pushed commit going to cause problems?

Question: I am using Git Extensions and my situation looks like this:

As you see, my target commit is not the last one. And it's already pushed and pulled by other users of the branch. I read some articles about using different commands through the git bash, for doing some work, but here I found an easier way - I right-click the target commit > Manipulate commit > Fixup commit and another window pops out. Then I am able to change the commit message (the green part), and apparently to push the changes, but I haven't done anything yet as, from what I read, this is gonna cause problems in future for the other users of the branch.
What could these "problems" be and how can I fix the commit + avoiding any problems in future?
Answer: Note: I don't use these GUIs and sometimes they do something a bit unexpected.  But in this case I expect it only does what I expect (as it were :-) ).
Fundamentally, git never actually changes anything in a commit.  If you do an "amend" operation, even if you don't first back up one or two commits in a branch, what git does underneath is to make a new commit, leaving the old one in the repo.
For instance, your commit chain looks like this.  All I have done is rewrite the vertical graphical version in a horizontal form (more suitable for text).
... - M - B - C - P   <-- master, origin/master
    /
...

where M is the "Merge branch 'deploy" commit, B is the first "blah, blah" commit, C is the one you want to change, and P is the pushed commit (the second "blah, blah" one).
Now, if you "detach" HEAD so that it points directly to commit C, you can run the command-line command git commit --amend, which seems like it's changing C.  Git brings up an editor with the original commit message and you can change the text and write and exit the editor, and git makes a new commit.  But what it does is not "change C".  Instead, it makes a copy of C, let's call it D, with the same files but different commit-text.  (If you modify some file(s) and git add them before doing git commit --amend, the changes you make to the files get associated with the new commit D; again, commit C remains entirely unchanged.)  This gives you a commit chain that looks like this:
... - M - B - C - P   <-- master, origin/master
    /       \
...           D       <-- HEAD

It is now possible to take commit P and copy it as well.  (You still can't change it—this is a feature of a git commit.  Git commits are frozen in time forever: their SHA-1 "true name" is a cryptographic checksum of your name as the commit author, the time-stamp at which you make the commit, the commit text, the commit's parent commits, and all the files and directories inside the commit; and changing a single bit anywhere in the commit, changes the SHA-1, and hence the "true name" of the commit.  The result is a new, different commit.)  Let's call the copy of P (with parent changed to D) E:
... - M - B - C - P   <-- master, origin/master
    /       \
...           D - E   <-- HEAD

It's possible your graphical tool will do this for you automatically, if you say "please change commit C": it will make a copy of C, with whatever changes you like, which becomes D; and then it will make copies of things on top of C—in this case, that means a copy of P—as well.  (Or more likely it doesn't bother copying "things on top of C" at all, forcing you to do it if you want that.)
You can now move your local branch label master to point to commit E instead of commit P.  In fact, git will sometimes even help you do that, with some commands.  (I have no idea what your GUI will do, I find GUIs mysterious and often annoying. :-) )  But, if you do that, you will have a "divergent" master branch, because the remote repo, the one at origin, has your commits C and P (because you successfully "pushed" them earlier).  And it has them on what it considers to be the master branch.

Side note: if you can log in to the machine origin, you can find the git repo over there and look at its idea of the various branch labels.  Over there, you will see master pointing to commit P.  That's why your repo has the "remote branch" label, origin/master, pointing to P: essentially, whenever your machine contacts the remote, it asks: "hey! what labels do you have?" The remote answers—it might say "I've got master and develop and they point to commits P and Q"—and then your git copies these over to your repo, but changes the names: master becomes origin/master, develop becomes origin/develop, and so on.  That's how you know what he knows.  Or, more precisely, you know what he knew, the last time you talked with him.  That could have been seconds ago and things might be totally different by now!

Anyway, suppose you move your master to point to commit E.  If you now ask to push these changes to origin, your git will tell his git: "hey, I have these new commits D and E and you should point your master to E!"  His git will look at those and say: "if I do that, I could forget about commits C and P.  Your commit E points back to D and then D points back to B, and C and P will become unreachable."  His git will reject your push unless you specify the "force" option.
If you do specify "force", his git might still reject it, but probably he'll take it.  Is this a "bad thing"?  Well, maybe.  You'll be OK, and the repo at origin will itself be OK.  But what about Joe, who copied your commits C and P down from origin just 17 seconds ago?  Next time he goes to origin he'll expect C and P to still be there, and they won't be.  Joe will have to figure out that someone (you) "rewound" the branch, "removing" commits C and P.
Git is all set up for, and everyone expects to handle, new commits to get added.  They don't usually expect old commits to "go away" like this.  Joe can fix this—his repo will still have C and P; git doesn't actually delete commits (unless they become unreferenced and are garbage-collected).  But he may have to do a lot of work to figure out what you did, and figure out that if he had new stuff that he had added on to P, he now needs to copy that to new commits that add on to E instead.  (Specifically, he has to make sure he does not accidentally copy commits C and P, which are now subsumed by D and E.)  So this could give Joe a headache.  And if Joe has these, maybe Sally and Frank and Irene have those commits too, and maybe you will be giving dozens of people headaches.
Is it bad?  Well, that depends on who has your old commits, how much of a headache you're going to give them by doing this, and whether you're allowed to give them headaches. :-)  If nobody has them—if you're very quick, or the rate at which people pick up changes you push is measured in days instead of seconds—you'll be fine.  If you give those who have your "bad" commits some warning, and they know what to do, you could be fine.  If not, well, who knows?
Comment: Note: recovering from a `git push -f` will be easier with Git 2.0: see http://stackoverflow.com/a/20423029/6309
Answer: The problem with rewriting history which has already been pushed is that other users already have the "original" history, with which your rewritten history will not be compatible anymore. So if you change the next-to-last commit (and a change in commit message is enough to do that, as the message is part of the commit's hash calculation) and force-push it to the server, any work someone else already has done based on the old version of that commit or any newer ones will not apply anymore (as it no longer has a valid ancestor in the branch). As pointed out here: RECOVERING FROM UPSTREAM REBASE

Rebasing (or any other form of rewriting) a branch that others have based work on is a bad idea: anyone downstream of it is forced to manually fix their history.

If the commit you want to fix is very recent and the chance is low that anyone else has done much based on it, do the interactive rebase, git push --force to the server, and tell the other contributors to git pull --force if they can do without their local changes. For rebasing existing work based on the rewritten commit, see the accepted answer here: How do I recover/resynchronise after someone pushes a rebase or a reset to a published branch?.
This is not a one-stop solution, because rewriting published history is cumbersome by design. If it's not absolutely necessary, don't do it.
Alternatives:
I don't know how severe your wrong commit message is (completely garbled, erroneous, incomplete?), but if you just need to clarify something, you can do
git notes add -m"<Comment or clarification>" [commit-id-if-not-HEAD]

Notes are kept seperately and can be changed/added/removed later, without affecting the history.
Answer: Several ways of solving this, (imho) cleanest is to rebase your commit on top of origins master.
This can be done interactively as such:
git rebase -i origin/master

Comment: Sorry, I didn't understand completely (I'm a newbe user of git). You mean, that I should change the commit message, then push it and then rebase ?
Comment: I'm sorry, maybe I misunderstood, I thought you were in the situation where your current commit was outdated because someone else pushed before you? You never change commits that may have been pulled by others, instead you make new commits to fix whatever was wrong with the first one. If you already changed your commit, reset your repository to origin/master and then make your changes anew.


Adams spectral sequence for computing 3-torsion in $\pi_*(S)$

Question: A novice to the Adams spectral sequence, I am attempting to follow a computation in McCleary's book in the mod 3 Adams spectral sequence for $\pi_*(S)$.  By working out part of a minimal resolution of $\mathbb{Z}/3\mathbb{Z}$ over the mod 3 Steenrod algebra, we compute $Ext^{s, t}_A(\mathbb{Z}/3\mathbb{Z}, \mathbb{Z}/3\mathbb{Z})$ for $t \leq 11$ and all $s$.  McCleary claims that there is a lack of differentials here, but I don't see why. If we arrange the spectral sequence with $t-s$ increasing horizontally to the right and $s$ increasing vertically, then $d_r$ goes left one space and up $r$ spaces.  In the $t-s=3$ column, for $s \leq 3$ there is only a generator in degree $s=2$ and there is nothing in the $s \leq 3$ range in the $t-s=2$ column.  But as far as I know, there could be nontrivial things in the $t-s=2$ column for large enough $s$ for which I don't know $Ext^{s, t}$ for $t=s+2$.  So conceivably, there is room for differentials here (from t-s=3, s=2 to something in the $t-s=2$ column).  Why does McCleary conclude that there aren't any, or what am I misunderstanding here?   Thanks!
Comment: I thought about it on the walk home, and I have a guess as to what is going on here.  In $P_3$, the third stage of our resolution, the first generator (besides the ones coming from the Bocksteins, which won't generate things that map to 0 on their own) occurs in degree greater than 11.  So something that maps to zero will be in at least one degree greater than 13, so the first non-Bockstein related generator in $P_4$ won't occur until at least 14.  In general, the first generator in $P_{s+3}$ won't occur until degree at least 13+s.  So we actually know the Ext groups for $t-s < 13+s-(s+3)=10$.
Comment: McCleary doesn't quite make this explicit.  Is this correct?
Comment: In the first comment above, the 11 should be a 13.
Answer: I am going to post more or less what I wrote in the comments above and maybe someone can tell me if this is correct.
I wrote that we know the resolution for $t \leq 11$ and all $s$, but something stronger is true.  In the $s$th stage of the resolution, we have a generator $a_s$ in degree $s$ which ultimately comes from the Bockstein $\beta$, and $d(\beta a_s)=0$, so we put a generator in the $(s+1)$ stage of the resolution in degree $s+1$ to map to $\beta a_s$.  No other product of an element of the Steenrod algebra (which is not in the ideal generated by $\beta$) and $a_s$ will map to zero, so all other things in the $s$ stage that map to zero must contain at least one other generator.  But in the 3rd stage of the resolution, the first generator not related to the Bockstein is in degree 13.  To find something in terms of this generator that maps to zero, we must multiply it by something in the Steenrod algebra, so the first non-Bockstein generator in the 4th stage appears in degree greater than or equal to 14.  Continuing in this way, the first non-Bockstein generator in the $s+3$ stage does not occur until degree at least $13+s$, and below that the only generator is $a_{s+3}$.  So we know the resolution for $t-s< 13+s-(s+3)=10$.  When we look at the $E_2$ page of the Adams spectral sequence, this means that we know the first 9 columns, and since diferentials go one to the left and $r$ units upward, from our computations we see that there are no differentials in this part of the spectral sequence.


Is there a way to keep bananas that are half submerged in milk fresh for at least 26-28 hours?

Question: I make a special drink that contains banana and milk and I drink it every morning, is there a way i can have it ready in a blender for up to 28 hours? I am unsure but i got a recommendation of putting the blender container in the fridge (not sure if i had to keep the lid open or not). What I am talking about here is the banana still uncut from the blender, but without its skin.
Comment: Why can't you mix and blend a fresh banana each morning ? it's not that time consuming and you will always use fresh(er) fruits and milk? no ?
Answer: Assumption here:
The main point where prepping what reads like two servings ("every morning" & "26-28 hours) might come handy, is when you have an uneven number of bananas per serving and storing half a banana is kind of impractical.
Have you considered freezing your fruit? In pieces, so that one banana is cut in an even number of pieces (& can thus be easily divided). Then when it's time to blend your breakfast drink, just add as many pieces of frozen banana as your recipe requires. No need to thaw the fruit, any reasonably strong blender should be able to deal with it.
This would allow you to

prepare the fruit for multiple servings at once
eliminate the question of keeping the fruit fresh
give you bananas that are always just the ripeness you prefer
lets you make good use of bananas on sale

If still want to go the bananas-in-milk route, it's essential that you refrigerate the whole thing: letting your milk stand at room temperature is not safe. That said, you can even refrigerate bananas that are already blended in milk for a day or two. Food-safety-wise totally fine and while you might see some browning, it's mainly about eye-appeal. So you could blend a two-day ration of bananas in milk.
If your drink contains more ingredients that can't be pre-blended, pour off and refrigerate half of the banana-milkshake, add the daily serving of the other ingredients and whizz to blend for a moment.
Answer: Put your blender jar in the refrigerator, covered, if possible.  Covering will keep odors from mingling and will prevent your the top of your banana from slightly dehydrating.  That said, cover off will be fine too.  It might oxidize a bit (turn brown), but that will not really impact your final product.


What is so special about Unix time?

Question: I don't understand the purpose of the Unix time / epoch, to my understanding the number of seconds elapsed since January 1st, 1970. This seems wholly arbitrary to me. Why not simply use a timestamp in the form of month, day, year?
Comment: How would you represent this timestamp of yours in memory? How many bytes of memory would that take? How many bytes of memory do you think they had in the 70s? :)
Comment: Measuring time in seconds is simpler than "simply" using three integers that you have to interpret in very, very screwy ways.
Answer: Not to get existential, but all time is arbitrary.
This year is 2014 A.D. meaning it's been 2014 years since the epoch used in the Julian and Gregorian calendars. You've got to have a reference or starting point in time, or epoch, and the engineers at Bell decided to pick their own.
Answer: From this wired article:

The date was programmed into the system sometime in the early 70s only because it was convenient to do so, according to Dennis Ritchie, one the engineers who worked on Unix at Bell Labs at its inception.

Quoting Ritchie himself:

"At the time we didn't have tapes and we had a couple of file-systems running and we kept changing the origin of time.  So finally we said, 'Let's pick one thing that's not going to overflow for a while.' 1970 seemed to be as good as any. "
Answer: I encourage you to watch this YouTube video: https://www.youtube.com/watch?v=-5wpm-gesOY
The tl;dr of the video is that countries deal with dates and times in massively inconsistent ways, and any programmer trying to deal with all of them is going to go crazy.
Rather than apply deltas to the date/time fields of your hypothetical struct (Which is a complicated calculation even when the delta stays constant relative to your base), having "time" as a single number means you just need to apply rules to a common base standard.

What is so special about Unix time?


Is fecal occult blood test (EZ Detect) effective if urine is in the toilet bowl?

Question: The patient used an EZ Detect fecal occult blood test.  The test was positive.  She saw a tiny blue circle on the piece of paper indicating trace of blood in her stool.  But, she indicated there was also urine in the toilet bowl.  Would urine affect this test?
Comment: Just curious, but didn't the directions that came with your hemoccult test give you all of this information?
Comment: No, it did not.
Comment: "Step 2: Urinate first and then flush the toilet; have a bowel movement; carefully drop a Test Tissue into the toilet bowl..." From instructions.
Answer: After doing some research on the issue, including contacting the company "Biomerica" and finding on the Internet the "Physician's Instruction Pamphlet" I did find that urine does affect such tests.  The mentioned pamphlet states: 1) Urinate first and then flush the toilet; 2) Have a bowel movement; 3) carefully drop a test tissue into the toilet bowl, etc.  Thus, Biomerica is adament that for the test to be reasonably accurate urine should be absent from the toilet bowl.  They also confirmed the same by email.
One should keep in mind that even if you take all those precautions you should understand that such tests are not "accurate" especially when they are positive.  This is due to such tests having a rather low sensitivity (true positive rate) combined with a disease that has a fairly low prevalence rate.  Quoting Wikipedia on fecal occult blood test with a positive result: "about 2-10% have cancer, while 20%-30% have adenomas."  Depending on one's circumstances those statistics can vary (age, sex) and increase a bit.  But, still a positive test result still leaves one much more likely to be free of colon cancer.  It is just an information piece that may suggest further test investigation may be warranted (colonoscopy, etc.).
In view of the above, following Biomerica's instructions I would not consider a positive test result with urine in the bowl as counting as a true positive test.  Instead, I would continue testing with the remaining test tissues and make sure I follow the appropriate protocol as indicated above.  If one would feel they did not have enough remaining test tissues, I would just get another set and re-test again.  If the individual does test negative three times in a row that should give her much comfort.  The test is far more accurate on "negatives" vs. "positives" because the test's specificity (true negative rate) is much above its sensitivity (true positive rate).
Comment: `such tests are not "accurate" especially when they are positive. This is due to such tests having a rather low sensitivity (true positive rate)....` -- When faced with a positive test, *specificity* rather than *sensitivity* is relevant.  "True positive rate" is ambiguous (if describing sensitivity it indicates the proportion of true positives that are correctly identified rather than the proportion of identified positives that are true), but in any case false positives are due to poor specificity.
Comment: The accuracy of a positive test is equal to: # true positive observations/(# true positive obs. + # false positive obs.).  So, sensitivity (true positive rate) plays an important role in both numerator and  denominator.  Specificity (true negative rate) plays a role in generating # false positive observations.  However, the big driver in generating # false positive obs. is not so much specificity but the prevalence rate of the specific disease being screened.  A test with high specificity testing a disease with low prevalence rate will still generate a lot of false positives.


No cold air - AC Compressor clutch engage with LP side 0 psi

Question: No cold air
AC Compressor clutch is engaged
Low pressure is "0"
tried to add Freon and immediately jumps to 150 psi
relieve pressure and again immediately back to 0 with clutch still engaged
never seen this before - how can the clutch be engaged with no pressure on LP side?
Comment: Welcome to Motor Vehicle Maintenance & Repair!
Answer: Most likely the system is plugged. You never state what your high side reading is ... more than likely it would scare you if you did see it. If it's plugged and you still have pressure on the high side, I can see that it might engage that way. It definitely wouldn't be good to run it too long that way. You also wouldn't see anything in the way of cooling going on, either. You don't mention anything about the vehicle in question, so can speculate no further on where that plug might be or what's going on beyond that.
Comment: High side 180 psi - and I have let the system run for the past hour and the lp side is now up to 30 psi.
Comment: 2009 Honda odyssey
Comment: I agree with your opinion - I can repair most issues but will pass on this one and will take to a professional thank you