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A second-order semilinear Volterra integrodifferential equation involving fractional time derivatives is considered. We prove existence and uniqueness of mild solutions and classical solutions in appropriate spaces.

In this paper, we investigate the existence of mild solutions of second-order initial-values problems for a class of semilinear differential inclusions with nonlocal conditions. By using suitable fixed-point theorems for multi-valued maps, we study the case where the multi-valued map F has convex or nonconvex values.

Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights.

eng_Latn

SEPARATION PROBLEM FOR STURM-LIOUVILLE EQUATION WITH OPERATOR COEFFICIENT

Let H be a separable Hilbert Space. Denote by H1 = L2(a,b; H) the set of function defned on the interval a < c < b (¾¥ a < c < b £¥) whose values belong to H strongly measurable [12] and satisfying the condition If the inner product of function ¦(c) and g(c) belonging to H1 is defined by then H1 forms a separable Hilbert space. We study separation problem for the operator formed by ¾ y"+ Q (c) y Sturm-Liouville differential expression in L2(¾ ¥, ¥; H) space has been proved where Q (c) in an operator which transforms at H in value of c,,self-adjoint, lower bounded and its inverse is complete continous

Complex geometric features in models would cause generation of redundant elements in finite element analysis.To reduce computation cost of complex models in the premise of acquirement of reliable analysis result,a method for assessing solution space discrepancy between the models before and after simplification is researched.Subdivisions and field functions of the models before and after simplification are compared respectively.Then,degree of such discrepancy can be estimated according to two classic interpolation error theorems for affinity-equivalent conforming elements and isoperimetric elements respectively.The method provides judgment to effectiveness of the simplification strategy.Theory deduction and experiments results indicate that the estimated discrepancy degree is consistent with discrepancy between the two corresponding solution spaces.

yue_Hant

Quantum Dynamical Algebra SU(1,1) in One-Dimensional Exactly Solvable Potentials

We mainly explore the linear algebraic structure like SU(2) or SU(1,1) of the shift operators for some one-dimensional exactly solvable potentials in this paper. During such process, a set of method based on original diagonalizing technique is presented to construct those suitable operator elements, J0, J_\pm that satisfy SU(2) or SU(1,1) algebra. At last, the similarity between radial problem and one-dimensional potentials encourages us to deal with the radial problem in the same way.

In this paper, we study the Dirichlet problem for a singular Monge-Ampere type equation on unbounded domains. For a few special kinds of unbounded convex domains,we find the explicit formulas of the solutions to the problem. For general unbounded convex domain $\Om$, we prove the existence for solutions to the problem in the space$C^{\infty}(\Om)\cap~C~(\overline{\Om})$. We also obtain the local $C^{\frac{1}{2}}$-estimate up to the $\partial~\Omega$ and the estimate for the lower bound of the solutions.

eng_Latn

A design study for an integer order bessel function of the first kind function generator for an analogue computer

The author suggests a method by which a function generator for an integer order Bessel function o f the first kind could be constructed, by making use o f a defining integral for these functions which involves the common trigonometric functions.

Given ?>0 andp?(0,1), we consider the following problem: findu such that $$\begin{gathered} - \Delta u + \lambda [u]_ + ^p = 0in\Omega , \hfill \\ u = 1on\partial \Omega , \hfill \\ \end{gathered} $$ whereΩ??2 is a smooth convex domain. We prove optimalH 1 andL ? error bounds for the standard continuous piecewise linear Galerkin finite element approximation. In addition we analyse a more practical approximation using numerical integration on the nonlinear term. Finally we consider a modified nonlinear SOR algorithm, which is shown to be globally convergent, for solving the algebraic system derived from the more practical approximation.

eng_Latn

Dynamics of a Néel domain wall with a fine structure in rare-earth orthoferrites

The dynamics of an isolated domain wall (DW) with a fine structure moving at a supersonic velocity in a rare-earth orthoferrite is studied. A set of nonlinear equations of motion of the center of a DW structure line is derived. A steady-state solution to these equations adequately describes the experimental data for yttrium orthoferrite. The effect of an external magnetic field on the steady-state velocity of a DW with structural lines is investigated.

Abstract We study a general nonlinear elliptic equation in the Orlicz setting with data not belonging to the dual of the energy space. We provide several Lorentz-type and Morrey-type estimates for the gradients of solutions under various conditions on the data.

eng_Latn

The Study on Mathematical Model for Double Porosity Medium with Well of Curves

In the oil production and thermal recovery in the application of oil and gas field, well of curves are regarded as the crooked canal(namely not only the canal has horizontal section but also vertical section), it instead the horizontal well before. Thus establishmented the new elbow well model, the solution of the model not only suitable for theoretical study but also easy to calculate in practical production. This article considered the problem of indeterminate percolation of spherical symmetry infinite domain described by the initial boundary value problem of the system of partial differential equation and obtained the point-source accurate solution when research on the problem of indeterminate percolation for double porosity medium. Abtained the accurate solution about mathematical model of line source from appling the point-source accurate solution, and applied the results to mathematical model of well of curves, obtained the integral expression of it’s accurate solution.

We deal with linear parabolic (in the sense ::: of Petrovskii) systems of order $2b$ with discontinuous principal ::: coefficients. A priori estimates in Sobolev and ::: Sobolev--Morrey spaces are proved for the strong solutions by ::: means of potential analysis and boundedness of certain singular ::: integral operators with kernels of mixed homogeneity. As a ::: byproduct, precise characterization of the Morrey, $BMO$ and ::: Holder regularity is given for the solutions and their ::: derivatives up to order $2b-1.$

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Vibrational modes of two violins

Using electronic TV holography, as well as other methods for observing vibrational motion and sound radiation, the normal modes of vibration in two violins have been studied. The principal modes observed in a Hutchins violin showed fairly good agreement with those reported by Marshall [J. Acoust. Soc. Am. 77, 695–709 (1985)] for the same violin. The strongly radiating T1 and C3 modes appear to be doublets, and this phenomenon is discussed. Vibrational modes excited by a force applied to the bridge by internal sound pressure, and by the sound field of a loudspeaker are compared.

We study the following bifurcation problem in a bounded domain in IR N : 8 : pu = juj jvj v + f(x; u; v; ) in qv = juj jvj u + g(x; u; v; ) in (u; v) 2 W 1;p 0 () W 1;q 0 () : We prove that the principal eigenvalue 1 of the following eigen- value problem 8

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Symmetry group methods for fundamental solutions

This paper uses Lie symmetry group methods to study PDEs of the form We show that when the drift function f is a solution of a family of Ricatti equations, then symmetry techniques can be used to find a fundamental solution.

Given ?>0 andp?(0,1), we consider the following problem: findu such that $$\begin{gathered} - \Delta u + \lambda [u]_ + ^p = 0in\Omega , \hfill \\ u = 1on\partial \Omega , \hfill \\ \end{gathered} $$ whereΩ??2 is a smooth convex domain. We prove optimalH 1 andL ? error bounds for the standard continuous piecewise linear Galerkin finite element approximation. In addition we analyse a more practical approximation using numerical integration on the nonlinear term. Finally we consider a modified nonlinear SOR algorithm, which is shown to be globally convergent, for solving the algebraic system derived from the more practical approximation.

eng_Latn

Holomorphic isometries from the Poincar\'e disk into bounded symmetric domains of rank at least two

We first study holomorphic isometries from the Poincar\'e disk into the product of the unit disk and the complex unit $n$-ball for $n\ge 2$. On the other hand, we observe that there exists a holomorphic isometry from the product of the unit disk and the complex unit $n$-ball into any irreducible bounded symmetric domain of rank $\ge 2$ which is not biholomorphic to any type-$\mathrm{IV}$ domain. In particular, our study provides many new examples of holomorphic isometries from the Poincar\'e disk into irreducible bounded symmetric domains of rank at least $2$ except for type-$\mathrm{IV}$ domains.

In this paper, we establish the local well-posedness for a new coupled Camassa-Holm system in a range of the Besov spaces by employing a series of norm estimates. A wave-breaking mechanism for solutions is described in detail and a result of blow-up solutions with certain profile is established.

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Renormalization group and variational treatments for a d-dimensional sine-Gordon model with correlated random fields

We study the effects of correlated symmetry-breaking-like random fields on critical properties of a d-dimensional sine-Gordon model. A Wilsonian renormalization group analysis shows an unusual scenario in the absence of stable fixed points. The physical nature of the related runaway in the parameter space is investigated by means of a complementary variational treatment. Self-consistent predictions for d>1 suggest that the disorder of the type considered here inhibits any phase transition with diverging correlation length and that the system lives in a “glassy-phase” at all temperatures.

Given ?>0 andp?(0,1), we consider the following problem: findu such that $$\begin{gathered} - \Delta u + \lambda [u]_ + ^p = 0in\Omega , \hfill \\ u = 1on\partial \Omega , \hfill \\ \end{gathered} $$ whereΩ??2 is a smooth convex domain. We prove optimalH 1 andL ? error bounds for the standard continuous piecewise linear Galerkin finite element approximation. In addition we analyse a more practical approximation using numerical integration on the nonlinear term. Finally we consider a modified nonlinear SOR algorithm, which is shown to be globally convergent, for solving the algebraic system derived from the more practical approximation.

eng_Latn

Generalized Budan-Fourier theorem and virtual roots

In this Note we give a proof of a generalized version of the classical Budan-Fourier theorem, interpreting sign variations in the derivatives in terms of virtual roots.

We study the following bifurcation problem in a bounded domain in IR N : 8 : pu = juj jvj v + f(x; u; v; ) in qv = juj jvj u + g(x; u; v; ) in (u; v) 2 W 1;p 0 () W 1;q 0 () : We prove that the principal eigenvalue 1 of the following eigen- value problem 8

eng_Latn

On Singular Systems of Parabolic Functional Equations

We consider systems consisting of an initial-boundary value problem for second-order quasilinear parabolic equation and an initial value problem for first-order ordinary differential equation where both equations contain functional dependence on the unknown functions.

In this work, we study the existence and multiplicity of positive solutions for the higher order p-Laplacian boundary value problem with even derivatives

eng_Latn

Boundary value problem for a parabolic-hyperbolic equation in a rectangular domain

In present paper we study a boundary value problem for a mixed parabolic-hyperbolic type equation in a rectangular domain and prove the existence of unique solution of this problem. In theory of boundary value problems for second order mixed type equations usually two conjugation conditions are in use. In this case, for mixed type equations containing hyperbolic equation in a rectangular domain for solvability of boundary value problem appears certain condition. In this paper we give three conjugation conditions. In this case mentioned condition not appears.

This study investigates the hydrodynamic performance of a submerged two layer horizontal plate breakwater. The plate thickness is considered as non-zero in the study. In the context of linear potential theory, an analytical solution for interaction of water waves with the plates is obtained using the matched eigenfunction expansion method. The solution consists of a symmetric part and an antisymmetric part. Its validity is confirmed by comparing the numerical results of reflection and transmission coefficients for limiting cases with previous predictions. Numerical examples are given to examine the major factors that affect the reflection and transmission coefficients of the plates. Some useful results are presented for engineering design.

eng_Latn

Existence of positive weak solutions for a new class of Kirchhoff elliptic systems with multiple parameters

In this paper, using sub-supersolution method, we study the existence of weak positive solution for a new class of Kirchhoff elliptic systems in bounded domains with multiple parameters.

In this paper,the design for eigenstructure assignment is discussed.The Linear Design Method for minimal order E-compensator is given,in which the attached P polse can be assigned in a stable(fixed,arbitrary)position.The uniformity of eigenstructure assignment capability for EO-compensator,E-compensator and state feedback is proved.

eng_Latn

A singular Monge-Ampère equation on unbounded domains

In this paper, we study the Dirichlet problem for a singular Monge-Ampere type equation on unbounded domains. For a few special kinds of unbounded convex domains,we find the explicit formulas of the solutions to the problem. For general unbounded convex domain $\Om$, we prove the existence for solutions to the problem in the space$C^{\infty}(\Om)\cap~C~(\overline{\Om})$. We also obtain the local $C^{\frac{1}{2}}$-estimate up to the $\partial~\Omega$ and the estimate for the lower bound of the solutions.

We describe preliminary results from an effort to quantify the uncertainties in parton distribution functions and the resulting uncertainties in predicted physical quantities. The production cross section of the $W$ boson is given as a first example. Constraints due to the full data sets of the CTEQ global analysis are used in this study. Two complementary approaches, based on the Hessian and the Lagrange multiplier method respectively, are outlined. We discuss issues on obtaining meaningful uncertainty estimates that include the effect of correlated experimental systematic uncertainties and illustrate them with detailed calculations using one set of precision DIS data.

eng_Latn

Pressure projection stabilizations for Galerkin approximations of Stokes' and Darcy's problem

In this study, we consider some recent stabilization techniques for the Stokes' problem and show that they are instances of the framework proposed by Brezzi and Fortin in "A minimal stabilisation procedure for mixed finite element methods" (Numer Math 89, (2001) 457). We also propose an analysis for Taylor-Hood elements with discontinuous pressures stabilized using penalization of the interelement pressure jumps. (c) 2007 Wiley Periodicals, Inc.

We describe preliminary results from an effort to quantify the uncertainties in parton distribution functions and the resulting uncertainties in predicted physical quantities. The production cross section of the $W$ boson is given as a first example. Constraints due to the full data sets of the CTEQ global analysis are used in this study. Two complementary approaches, based on the Hessian and the Lagrange multiplier method respectively, are outlined. We discuss issues on obtaining meaningful uncertainty estimates that include the effect of correlated experimental systematic uncertainties and illustrate them with detailed calculations using one set of precision DIS data.

eng_Latn

Existence of Non-negative Solutions of Nonlinear Third order Eigenvalue Problems

The authors consider the nonlinear third order differential equationsu+ρ~3u=λg(t)f(u),\ 0t2π(B)with the periodic boundary conditionsu~((i))(0)=u~((i))(2π),\ i=0,1,2(E)Where ρ∈0,13 is a constant,λ0 is a parameter.Two results on the existence of non-negative solutions to problem(B)-(E) are obtained.And the proof uses the fixed point ndex in the cone theory.

In this paper, we study the qualitative behavior of following open-access anchovy fishery model:    c x p y y y x d ax x v n n n n v n b n n    , where   , , , , , , , p v d c b a and the initial conditions 0 0 , y x are positive real numbers. More precisely, we investigate the necessary and sufficient condition for local asymptotic stability of the unique positive equilibrium point of this system. Some numerical examples are given to verify our theoretical results.

eng_Latn

Oligopolistic Entry Deterrence under Incomplete Information

Recent work has investigated the effects of asymmetric information between an incumbent firm and a potential entrant. This study extends the analysis to allow the initial market structure to be a noncooperative oligopoly. We show that there is a Bayesian Nash equilibrium in which the incumbent firms, although unable to collude, strategically deter entry that would have occurred under complete information. In contrast to the past limit-pricing literature, it is a high price that deters entry as it signals to the potential entrant that this is a high-cost industry. Extending the model to allow for multiple potential entrants, we find that increasing the degree of potential competition raises the preentry price and reduces the likelihood of entry.

Given ?>0 andp?(0,1), we consider the following problem: findu such that $$\begin{gathered} - \Delta u + \lambda [u]_ + ^p = 0in\Omega , \hfill \\ u = 1on\partial \Omega , \hfill \\ \end{gathered} $$ whereΩ??2 is a smooth convex domain. We prove optimalH 1 andL ? error bounds for the standard continuous piecewise linear Galerkin finite element approximation. In addition we analyse a more practical approximation using numerical integration on the nonlinear term. Finally we consider a modified nonlinear SOR algorithm, which is shown to be globally convergent, for solving the algebraic system derived from the more practical approximation.

eng_Latn

Mixed quasi-equilibrium-like problems

We use the auxiliary principle technique in conjunction with the Bregman function to suggest and analyze a three-step predictor-corrector method for solving mixed quasi-equilibrium-like problems. We also study the convergence criteria of this new method under some mild conditions. As special cases, we obtain various new and known methods for solving variational-like inequalities and related optimization problems.

We prove existence of solutions for a class of systems of subelliptic PDEs arising from Mean Field Game systems with H\"ormander diffusion. These results are motivated by the feedback synthesis Mean Field Game solutions and the Nash equilibria of a large class of $N$-player differential games.

eng_Latn

Robust exponential stability of uncertain systems with time-varying delays

Focuses on the problem of robust exponential stability of a class of uncertain systems described by functional differential equations with time-varying delays. The uncertainties are assumed to be continuous time-varying, nonlinear, and norm bounded. Sufficient conditions for robust exponential stability are given for both single and multiple delays cases.

In this paper we will study the existence of solutions for the nonhomogeneous elliptic equation with variable exponent $\Delta^2_{p(x)} u=\lambda V(x) |u|^{q(x)-2} u$, in a smooth bounded domain,under Neumann boundary conditions, where $\lambda$ is a positive real number, $p,q: \overline{\Omega} \rightarrow \mathbb{R}$, are continuous functions, and $V$ is an indefinite weight function. Considering different situations concerning the growth rates involved in the above quoted problem, we will prove the existence of a continuous family of eigenvalues.

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CANONICAL FORMULATION OF A BOSONIC MATTER FIELD IN (1 + 1)-DIMENSIONAL CURVED SPACE

We study a bosonic scalar in (1 + 1)-dimensional curved space that is coupled to a dynamical metric field. This metric, along with the affine connection, also appears in the Einstein–Hilbert action when written in first-order form. After applying the Dirac constraint formalism to the Einstein–Hilbert action and the action of the bosonic scalar field separately, we apply it to these actions when they are combined. Only in the latter case does a dynamical degree of freedom emerge.

In this paper, we study the Dirichlet problem for a singular Monge-Ampere type equation on unbounded domains. For a few special kinds of unbounded convex domains,we find the explicit formulas of the solutions to the problem. For general unbounded convex domain $\Om$, we prove the existence for solutions to the problem in the space$C^{\infty}(\Om)\cap~C~(\overline{\Om})$. We also obtain the local $C^{\frac{1}{2}}$-estimate up to the $\partial~\Omega$ and the estimate for the lower bound of the solutions.

yue_Hant

On Best Polynomial Approximations in L2

For the τ-moduli of smoothness of mth order, we calculate exact constants in Jackson-type inequalities. We also obtain the exact values of the n-widths of classes of functions whose rth derivatives are characterized by τ-moduli of smoothness majorized by functions satisfying certain constraints. We present an example of the majorant for which all the stated requirements are satisfied.

In this work, we study the existence and multiplicity of positive solutions for the higher order p-Laplacian boundary value problem with even derivatives

eng_Latn

Necessary Conditions of Weak Efficiency for a Class of Nondifferentiable Vector Optimization Problems

the Kuhn-Tucker type necessary conditions for weak efficiency are given for a class of the problem of minimizing a vector function of which each component is the sum of a differentiable function and a convex function subject to a set of differentiable nonlinear inequalities on an open subset X of R~n,under the weaker constraint qualification.The results obtained improve and extend some of the existing results in the literature.

In this paper, we study the sharp energy criteria of blow-up and global existence for the nonlinear Klein-Gordon equation by the sharp Gagliardo-Nirebergy-Sobolev inequality.

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Positivity and strong ellipticity

We consider second-order partial differential operators $H$ in divergence form on $\Ri^d$ with a positive-semidefinite, symmetric, matrix $C$ of real $L_\infty$-coefficients and establish that $H$ is strongly elliptic if and only if the associated semigroup kernel satisfies local lower bounds, or, if and only if the kernel satisfies Gaussian upper and lower bounds.

In this work, we study the existence and multiplicity of positive solutions for the higher order p-Laplacian boundary value problem with even derivatives

eng_Latn

Existence of nonzero weak solutions for a class of elliptic variational inclusions systems in R N

We consider the following variational inclusions system of the form −� u + u ∈ ∂1 F(u ,v ) in R N , −� v + v ∈ ∂2 F(u ,v ) in R N ,

In this article we study the waves equation on an high-tension pillars with alveolar form. Geometric, high-tension pillars are represented by a thin, tall structure where the edge base is denoted by e, the thickness of the material - distributed along the layers is denoted by  and the alveoli is distributed with the period  . The parameters ,, e   are considered small, e   . This article consists in passing to the limit after 0 e  , 0   , 0   in this order, in the problem of the free vibration, the result is a mixed problem for the one-dimensional wave equation, in which the homogenized coefficient that appears is a combination between the constants that characterized the material. The result of our paper is identically with the result from (3).

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On the third-body perturbations of high-altitude orbits

The long-term effects of a distant third-body on a massless satellite that is orbiting an oblate body are studied for a high order expansion of the third-body disturbing function. This high order may be required, for instance, for Earth artificial satellites in the so-called MEO region. After filtering analytically the short-period angles via averaging, the evolution of the orbital elements is efficiently integrated numerically with very long step-sizes. The necessity of retaining higher orders in the expansion of the third-body disturbing function becomes apparent when recovering the short-periodic effects required in the computation of reliable osculating elements.

In present paper we study a boundary value problem for a mixed parabolic-hyperbolic type equation in a rectangular domain and prove the existence of unique solution of this problem. In theory of boundary value problems for second order mixed type equations usually two conjugation conditions are in use. In this case, for mixed type equations containing hyperbolic equation in a rectangular domain for solvability of boundary value problem appears certain condition. In this paper we give three conjugation conditions. In this case mentioned condition not appears.

eng_Latn

Hepp's bound for Feynman graphs and matroids

We study a rational matroid invariant, obtained as the tropicalization of the Feynman period integral. It equals the volume of the polar of the matroid polytope and we give efficient formulas for its computation. This invariant is proven to respect all known identities of Feynman integrals for graphs. We observe a strong correlation between the tropical and transcendental integrals, which yields a method to approximate unknown Feynman periods.

Given ?>0 andp?(0,1), we consider the following problem: findu such that $$\begin{gathered} - \Delta u + \lambda [u]_ + ^p = 0in\Omega , \hfill \\ u = 1on\partial \Omega , \hfill \\ \end{gathered} $$ whereΩ??2 is a smooth convex domain. We prove optimalH 1 andL ? error bounds for the standard continuous piecewise linear Galerkin finite element approximation. In addition we analyse a more practical approximation using numerical integration on the nonlinear term. Finally we consider a modified nonlinear SOR algorithm, which is shown to be globally convergent, for solving the algebraic system derived from the more practical approximation.

eng_Latn

Pohozaev identity for p-harmonic equation

This paper demonstrates the Pohozaev identity for p-harmonic equation from which the nonexistence of nontrivial solution for p-harmonic equation with critical growth is obtained.

Function theoretic methods in the complex plane are used to develop simple parametric hodograph formulas that generate sharp boundary equilibria of arbitrary shape. The related method of Gorenflo [Z. Angew. Math. Phys. 16, 279 (1965)] and Merkel (Ph.D. thesis, University of Munich, 1965) is discussed. A numerical technique for the construction of solutions, based on one of the methods, is presented. A study is made of the bifurcations of an equilibrium of general form.

eng_Latn

Two-parameter nonresonance condition for the existence of fourth-order boundary value problems

Abstract In this paper, we discuss the existence of the fourth-order boundary value problem { u ( 4 ) = f ( t , u , u ″ ) , 0 t 1 , u ( 0 ) = u ( 1 ) = u ″ ( 0 ) = u ″ ( 1 ) = 0 , where f : [ 0 , 1 ] × R × R → R is continuous, and partly solve the Del Pino and Manasevich's conjecture on the nonresonance condition involving the two-parameter linear eigenvalue problem. We also present a two-parameter nonresonance condition described by circle.

Abstract: We study the pointwise behavior of the Fourier transform of the spectral measure for discrete one-dimensional Schrödinger operators with sparse potentials. We find a resonance structure which admits a physical interpretation in terms of a simple quasiclassical model. We also present an improved version of known results on the spectrum of such operators.

eng_Latn

Gradient estimates for problems with Orlicz growth

Abstract We study a general nonlinear elliptic equation in the Orlicz setting with data not belonging to the dual of the energy space. We provide several Lorentz-type and Morrey-type estimates for the gradients of solutions under various conditions on the data.

In this paper we discuss the approximations introduced in the average-ion model usually employed for level population calculations. An improved system of equations of higher-order approximation is given. It is proved that in electric dipole approximation the level population probability Pnlj is independent of the quantum number j. leading to a great reduction of the number of equations to be solved. Finally, a method feasible for calculating these rate equations is suggested.

eng_Latn

Assessing Mathematical Forms employed to Describe Evolutions of Perturbations Propagating inside Optical Fibers

Comparisons have been made with different mathematical forms used to represent perturbation fields in studying the modulation instability happened in optical fibers. Without an artificial constraint, self consistent solutions to the linearized nonlinear Schrodinger equation can be deduced, which has recovered a rich variety of evolution characteristics at the initial stage for the perturbations co-propagating with a strong CW radiation inside the optical fiber. Although previous theories have correctly predicted the perturbation gain coefficient, an effort of seeking a constant gain coefficient as suggested in literatures has directly focused the discussions to the asymptotic characteristics of perturbations and therefore failed to give a comprehensive description to the evolutions.

Given ?>0 andp?(0,1), we consider the following problem: findu such that $$\begin{gathered} - \Delta u + \lambda [u]_ + ^p = 0in\Omega , \hfill \\ u = 1on\partial \Omega , \hfill \\ \end{gathered} $$ whereΩ??2 is a smooth convex domain. We prove optimalH 1 andL ? error bounds for the standard continuous piecewise linear Galerkin finite element approximation. In addition we analyse a more practical approximation using numerical integration on the nonlinear term. Finally we consider a modified nonlinear SOR algorithm, which is shown to be globally convergent, for solving the algebraic system derived from the more practical approximation.

eng_Latn

The lattice of Fitting classes which are right extensible by soluble groups

In this paper we study the set of Fitting classes which are right extensible by soluble groups ordered by the inclusion relation. The consideration of the associated lattices gives rise to new Fitting classes and it allows to obtain some injectivity criteria for general Fitting classes.

Given ?>0 andp?(0,1), we consider the following problem: findu such that $$\begin{gathered} - \Delta u + \lambda [u]_ + ^p = 0in\Omega , \hfill \\ u = 1on\partial \Omega , \hfill \\ \end{gathered} $$ whereΩ??2 is a smooth convex domain. We prove optimalH 1 andL ? error bounds for the standard continuous piecewise linear Galerkin finite element approximation. In addition we analyse a more practical approximation using numerical integration on the nonlinear term. Finally we consider a modified nonlinear SOR algorithm, which is shown to be globally convergent, for solving the algebraic system derived from the more practical approximation.

eng_Latn

Coupled Oscillators in Quenched Random Potential

We study a synchronization of coupled oscillators in quenched random potential by numerical simulations as a model of sliding charge density waves and flux line lattices. By changing external driving force, we find a percolation transition of a cluster with a same frequency in a finite time observation. Percolating cluster, however, becomes unstable in the long time limit while finite size systems fall into limit cycle motion.

ABSTRACTThis paper aims to develop, assess, and numerically implement analytical models for the newly introduced Quintuple Friction Pendulum Isolator (QFPI) which can identically capture its real e...

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V.A. Marchenko and E.Y. Khruslov: Homogenization of Partial Differential Equations

This book, which was first published in Russian in 2005, deals with the homogenization of partial differential equations (pdes) of elliptic and parabolic types. The authors study both boundary value problems posed in highly perforated domains or equations with rapidly oscillating coefficients. The standard theory of homogenization (periodic theory, uniformly elliptic oscillating coefficients) is supposed to be already known and the emphasis is put on nonstandard situations leading to multicomponent or nonlocal equations.

Abstract The high frequency modes of Hamiltonian systems tend to have small amplitudes. Hence for moderately accurate integration of such problems by, say, the leapfrog method the time step tends to be limited by stability restrictions rather than accuracy restrictions. Conventional implicit symplectic methods like implicit midpoint have less severe stability restrictions but the cost of solving large nonlinear systems with dense Jacobian matrices is probably too high to make them worthwhile. To bring down the cost of implicit methods, we have designed (i) mixed implicit-explicit, and (ii) linearly implicit methods that retain the property of being symplectic.

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Relaxation oscillations in a kinetic model of catalytic hydrogen oxidation involving a chase on canards

Abstract A detailed study of two- and three-variable mathematical models of a heterogeneous catalytic system is presented with special attention to weakly stable dynamics, a type of complex irregular behavior frequently encountered in oscillating chemical reactions. One of the most important properties of the weakly stable dynamics is “a sensitive dependence on the initial conditions”. Our analysis of a global error in long-term numerical integration shows that a high sensitive dependence on the initial conditions appears in the three-variable system with fast, intermediate and slow variables due to existence of the canard cycles which occur close to Hopf bifurcation in the one-parameter family of two-variable subsystems.

With the FEM analysis soft ware NX Nastran,this paper achieves the buckling response analysis according to various structural dimension、work speed、disturbing force on the HSK tool system.The computing results and correlative conclusions can be regarded as the basis of structure stability and failure mechanism analysis,and provides the theoretical guidance HSK tool system's type selection and appropriately used in the high speed machining occasion.

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Features of the Triple Helix Model in Cross-Border Clusters

The article is aimed at discussing the unique characteristics of the “triple helix” model that are unveiled while applied to cross - border cluster studies. The results of the case study method of the best practice on cross - border cluster formation at the Baltic Sea region shows evidence of the doubling of the number of helices represented in a complex collaboration system. Major factors of the dynamics and the transformation of the cross-border cluster interactions are stated. The hypothesis of the “double triple helix” model is suggested and the illustration of the case study example of the “Medicon Valley” is given.

In this lecture we present an overview of some recent results on temporal and spatial structures in chemical systems far from equilibrium. We discuss experiments on multiple stationary states (bi- and tristabilities), hysteresis of unstable stationary states, limit cycles, generation of limit cycles by periodic external perturbations, regular and Hopf bifurcations, chemical fronts, time-independent spatial structures and periodic precipitation processes.

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Bus Routes Optimization and Adjustment Based on the Optimal Service Capability of Urban Bus Stop

A large number of urban bus routes and bus stops are clustered in the central business area, which provides the mobility for the city residents but brings about traffic-related problems at the same time. For example, one of the common phenomena is that many buses are seriously delayed at the bus stop, particularly in the rush hours. The paper attempts to minimize the total delay of the buses at the same stop through analyzing the characteristics of bus routes and docking time of the buses, taking into account the temporal characteristics of the docking buses and the passengers' demand, and finally determining the optimal capacity of the bus stop. The paper proposes a new approach to reduce the redundancy of bus routes at the same stop. The paper also verifies the practicability of the model through a case study.

In this paper the dynamics of a discrete-time prey-predator system is investigated in the closed first quadrant . The existence and stability of fixed points are analyzed algebraically .The conditions of existence for flip bifurcation is derived by busing center manifold theorem and bifurcation theory. Numerical simulations not only illustrate our results but also exhibit complex dynamical behaviors of the model, such as the periodic-doubling bifurcation in periods 2,4 and 8 and quasi-periodic orbits and chaotic sets. Keywords : Discrete Model, Beddington-Deangelis Functional Response, Stability, Flip Bifurcation, Center Manifold Theorem, Numerical Simulation.

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Global Dynamics of a Piecewise Smooth System for Brain Lactate Metabolism

In this article, we study a piecewise smooth dynamical system inspired by a previous reduced system modeling compartimentalized brain metabolism. The piecewise system allows the introduction of an autoregulation induced by a feedback of the extracellular or capillary Lactate concentrations on the Capillary Blood Flow. New dynamical phenomena are uncovered and we discuss existence and nature of two equilibrium points, attractive segment, boundary equilibrium and periodic orbits depending of the Capillary Blood Flow.

W 'J *J J LBL-9998 I B Lawrence Berkeley Laboratory UNIVERSITY OF CALIFORNIA Materials & Molecular Research Division D O C U M E N T S SECTION. THE LOOP-DRIVEN GRAPHICAL UNITARY GROUP APPROACH TO THE ELECTRON CORRELATION PROBLEM, INCLUDING CONFIGURATION INTERACTION ENERGY GRADIENTS Bernard Robinson Brooks ( Ph. D. thesis ) For Reference September 1979 Not to be taken from this room r •-Si Prepared for the U.S. Department of Energy under Contract W-7405-ENG-48

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Adiabatic calorimeter as an ultra-low frequency spectrometer

High themdl stability and temperature resolution of the adiabatic calorimetry mke it possible to study freezing process of disorder existing in coladensed mtters. liquids around their glass transition regions. It turned out that the enthalpy relaxatim phenanenon occurreed also in crystalline materials associated with the freezing of relevant degree of freedam Since the measurement is based on the time evolution of enthalpy through the observation of temperature change under adiabatic condition, the adiabatic calorimetry belongs to time-danain spectroscopy corresponding to the frequency range between 10 mHz and 1 pHz. applicability to a wide range of substances indepndently of the chenical nature and physical state. occurring in several crystals are reviewed here with their implications. This was first demonstrated for

This paper considers a transient heat conduction problem for an infinite medium with two non-overlapping circular cavities. Suddenly applied, steady Dirichlet type boundary conditions are assumed. The approach is based on superposition and the use of the general solution to the problem of a single cavity. Application of the Laplace transform results in a semi-analytical solution for the temperature in the form of a truncated Fourier series. The large-time asymptotic formulae for the solution are obtained by using the analytical solution in the Laplace domain. The method can be extended to problems with multiple cavities and inhomogeneities.

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Film condensation heat transfer on a horizontal tube in presence of a noncondensable gas

The double boundary layer model has been developed to study the behavior of film condensation heat transfer outside a horizontal tube in presence of air treated as a noncondensable gas. And the coupled heat and mass transfer on a smooth horizontal tube is numerically solved with the finite difference method. The local mass concentration of the noncondensable gas, the distributions of velocity and temperature in the boundary layers are presented and discussed. The numerical results have shown that the mass concentration and velocity of the noncondensable gas increase from the bulk mixture to the interface while the temperature decreases from the bulk mixture to the interface. Although the mass concentration of the noncondensable gas in the bulk mixture could be small, the reduction in average heat transfer coefficient is obvious. The comparisons of heat transfer coefficient show that the numerical predictions agree well with available experimental data.

The time sequences of the molecular dynamics simulation for the folding process of a protein is analyzed with the inherent structure landscape which focuses on configurational dynamics of the system. Time dependent energy and entropy for inherent structures are introduced and from these quantities a conformational temperature is defined. The conformational temperature follows the time evolution of a slow relaxation process and reaches the bath temperature when the system is equilibrated. We show that the nonequilibrium system is described by two temperatures, one for fast vibration and the other for slow configurational relaxation, while the equilibrium system is by one temperature. The proposed formalism is applicable widely for the systems with many metastable states.

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Pattern dynamics in inhomogeneous active media

We study pattern dynamics in inhomogeneous active media described by a reaction–diffusion model. This is done by means of numerical simulations in one-, two- and three-dimensional systems with radial symmetry. We consider inhomogeneities corresponding to the space variation of the (nonlinear) reaction characteristic of the system. Two different problems are treated: a bistable domain immersed in an oscillatory medium and an oscillatory domain immersed in an excitable medium. The different complex behaviours arising in these systems are studied.

Summary: A medium containing propamidine is described which has high selective activity for the species Bacillus anthracis. The spore form of the organism is essential as inoculum for the medium.

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Reactive catalytic fast pyrolysis process and system

This invention is directed to the discovery of a reactive catalytic fast pyrolysis (RCFP) process utilizing hydrogen at low pressures.

Abstract We study the dynamics of a wrinkled flame held downstream of a cold, isothermal, flat burner The analysis is conducted in the framework of a thermal diffusional flame model. An Arrhenius rate with a large activation temperature and a single reactant with Lewis number unity are postulated We show that the nonlinear evolution equation for the front shape and position is no longer local, neither in time nor in space, when the flame is sufficiently close to the burner surface.

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Multigrid and preconditioning strategies for implicit PDE solvers for degenerate parabolic equations

The novel contribution of this paper relies in the proposal of a fully implicit numerical method designed for nonlinear degenerate parabolic equations, in its convergence/stability analysis, and in the study of the related computational cost. In fact, due to the nonlinear nature of the underlying mathematical model, the use of a fixed point scheme is required and every step implies the solution of large, locally structured, linear systems. A special effort is devoted to the spectral analysis of the relevant matrices and to the design of appropriate iterative or multi-iterative solvers, with special attention to preconditioned Krylov methods and to multigrid procedures: in particular we investigate the mutual benefit of combining in various ways suitable preconditioners with V-cycle algorithms. Numerical experiments in one and two spatial dimensions for the validation of our multi-facet analysis complement this contribution.

The complex dynamics of an autonomous prey-predator system with impulsive state feedback control is studied. The sufficient conditions for the existence and stability of semi-trivial are obtained by using the Poincare map. Numerical simulations show that the complex dynamics of system we considered, including the doubling-bifurcations, chaos, etc

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Conjugate Heat Transport Systems

In this chapter, we further employ the law of motive force, a physical principle, to a class of more complicated situation of conductive–convective conjugate heat transfer problems. We provide a complete analytical solution for a classically unsolved problem of generalized Pohlhausen’s solution of forced convection with Hartee’s velocity profile in relation to the design of thermal insulation systems. Initially, the law of motive force is employed to a nonconjugate heat transfer problem with assumed boundary layer type variation of convective heat transfer coefficient.

. Such inverse problems arise in the study ofheat and mass transfer, diffusion, tracer dispersion, etc.Among the works concerning such problems, we notethose by Yu.E. Anikonov, Yu.Ya. Belov, M. Ivanchov,and some other authors (see the bibliography in [1–5]).However, previous studies considered linear or the sim-plest quasilinear cases, the governing equations werefrequently one-dimensional, and their coefficients gen-erally did not depend on x ’’ .rxt(),∂u∂t------ – L

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A speculative study of non-linear Arrhenius plot by using fractional calculus

In this study, the Van't Hoff differential equation is taken under consideration by making use of fractional derivative tools. In this context, the nonlinear Arrhenius behaviour can be obtained and some experimental values of reaction rate as function of temperature were fitted, with the proposed model. The new model showed better performance to fit rate constant data for different kinetics process, when compared with Arrhenius law. In these case, the Van't Hoff differential equation with noniteger order found relative percentage error less that 3% within experimental error. The fractional order plays an important role in modeling temperature dependence of these kinetic processes. Thus it provides a new perspective in the handling of many problems (e.g., as solubility as function of temperature; temperature dependency of the viscosity and conductivity, etc).

The gracefulness of graph R(4,5,n) are discussed.The graceful labelings are given.It also proves that graph R(4,5,n) are alternating graph.

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Vibration isolation system using zero-power magnetic suspension is modified to be equipped with a weight support mechanism. The original system has a problem that the whole weight of the isolation table must be supported solely by the attractive force produced by permanent magnets. It is an obstacle to develop large isolation tables. In order to overcome this obstacle, a weight support mechanism is introduced in parallel with the serial connection of a zero-power magnetic suspension system and a normal spring. It can reduce the static load force that the zero-power magnetic suspension has to support. The basic characteristics of the modified system are shown analytically. Experimental study demonstrates that the modified system maintains infinite stiffness against direct disturbance even if such a weight support mechanism is added.

This paper presents a six-axis hybrid vibration isolation system by an active zero-power control in combination with a passive weight support mechanism in order to develop a large vibration isolation table. The use of active zero-power control and weight support mechanism is the salient feature of the proposed system which enables to develop a vibration isolator with low power consumption and low cost. The system is capable to isolate as well as to control vibrations from different sources in addition to suppress large payloads or support large table. The basic characteristics of the developed system are elaborately discussed analytically. The proposed control technique can control all the motions of the system. The performance of the controller is evaluated by conducting several experiments.

This paper presents a six-axis hybrid vibration isolation system by an active zero-power control in combination with a passive weight support mechanism in order to develop a large vibration isolation table. The use of active zero-power control and weight support mechanism is the salient feature of the proposed system which enables to develop a vibration isolator with low power consumption and low cost. The system is capable to isolate as well as to control vibrations from different sources in addition to suppress large payloads or support large table. The basic characteristics of the developed system are elaborately discussed analytically. The proposed control technique can control all the motions of the system. The performance of the controller is evaluated by conducting several experiments.

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Experimental and numerical study on an ultrasonic horn with shape designed with an optimization algorithm

A New Approach on Vibrating Horns Design

Three-dimensional vortex structures under breaking waves

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Flutter-critical velocity is usually estimated from deterministic analyses by assuming that physical and geometrical parameters are perfectly known. However, aleatory and epistemic uncertainties, especially those associated with the definition of material properties, are intrinsically present partly because of the random nature of every physical system and partly because those properties are evaluated from a finite number of observations. The paper focuses on the combination of structural reliability analysis with aeroelastic simulation to give a correct flutter speed evaluation for design purposes. Two typical aeronautical test cases have been considered: (1) an isotropic material structure and (2) a composite material structure. Different computational methodologies (classical and developed by authors) have been coupled with a simple two-dimensional aeroelastic model to study the qualitative consequences of uncertainty in determination of critical flutter speed and to provide a comparison between differ...

In this study, flutter uncertainty analysis of an aircraft wing subjected to a thrust force is investigated using fuzzy method. The linear wing model contains bending and torsional flexibility and ...

We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero.

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This study concentrates to an effect usually called quasi-periodic response. Double degree of freedom (DDOF) spherical pendulum as an auto-parametric system is used to demonstrate and investigate this effect. Sweeping the excitation frequency throughout the auto-parametric resonance interval, various types of quasi-periodic response can be encountered. An analytical-numerical approach of these effects is developed using the original non-linear system. Relevant differential system in ''slow time'' is presented, which provides periodic, orbital and a few singular solutions separating basic response types. Numerical evaluation of typical cases and comprehensive parametric study are included. Some open problems are indicated.

The paper presents the results of numerical investigations of the overhead travelling cranes load motion. The model studies assumes that the load is suspended on the inextensible rope. Conversely, its motion is triggered by an external moment. In addition, energy losses in the construction node connecting the rope to the drum are included. At the same time these losses were mapped through a linear viscous damper. The main objective was to evaluate the impact of individual mathematical model parameters on the dynamics of the transported load. The results were compared between two models: with/without crane structure vibrations included. The results were illustrated by multi-colored maps of the largest Lyapunov exponent, bifurcation diagrams, and Poincare cross-sections.

Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights.

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Cylindrical shells under partially distributed radial loading

The elastic solution to the fundamental problem of a cylindrical shell subjected to a symmetric, partially distributed, and self-balanced radial pressure loading acting on the external surface is obtained under plane strain condition. A dual series approach based on Airy`s stress functions is employed yielding an exact solution to an auxiliary composite cylindrical assembly problem. The solution for the problem under study is then derived as a limit case of the auxiliary composite cylinder problem. It is proven that the more generalized solution presented here may be used to recover several well-known classical results. The solutions also agree very well with the numerical results obtained from a finite element analysis performed for one sample hollow shell problem. The rigorous expressions found in this analysis for the stress and displacement fields are applicable to both thin and thick-walled shells, including piping.

A general performance comparison of fuel element configurations having cell dimensions compatible with the OMRE grid structure was conducted. Resuits show that plates and rods are almost equivalent, and both are superior to concentric rings in nuclear and thermal performance (J.R.D.)

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Free Vibration of Thin Circular Plates Resting on an Elastic Foundation with a Variable Modulus

AbstractAn exact solution is established pertaining to the problem of undamped free vibration of a thin circular plate resting on a Winkler foundation with variable subgrade modulus. The solution is performed by applying the infinite power series method. Moreover, the solution procedure is demonstrated through an illustrative example, wherein the general frequency equation is derived for two different boundary conditions. The correctness of the solution is also verified using results available in the literature. Finally, it is shown that the proposed method of solution is directly applicable to the more-general problem of circular plates on a variable-modulus Pasternak-type foundation.

We study the initial boundary value problem for the nonlinear viscoelastic wave equation with strong damping term and dispersive term. By introducing a family of potential wells we not only obtain the invariant sets, but also prove the existence and nonexistence of global weak solution under some conditions with low initial energy. Furthermore, we establish a blow-up result for certain solutions with arbitrary positive initial energy (high energy case)

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L 2 regularity of measurable solutions of a finite-difference equation of the circle

We show that if $\varphi$ is a lacunary Fourier series and the equation $\psi (x) -\psi (x + \alpha) = \varphi(x), x \bmod 1$ has a measurable solution $\varphi$, then in fact the equation has a solution in L2. ::: ::: This work of Michel Herman (1942-2000) appeared only as a preprint of the Mathematics Institute, University of Warwick, dated May 1976. It was turned into TEX format by Claire Desescures. Minor editorial work was done by Albert Fathi.

The main objective of this study is to evaluate ball bearing defects under different operation conditions through vibration measurements. There are several tests conducted for healthy and defective bearing under variable speeds and load conditions. Experimental tests are conducted for six sets of ball bearings. Initially, a good bearing is fastened in the test rig and vibration signals are measured using the FFT analyzer to show the base-line performance of a healthy bearing. Then, the good bearing is exchanged by defective bearing and vibration signals are measured for each case separately under the same operation condition. Frequency domain, time domain and root-mean-square are used to describe various bearing defects. The experimental results are showed that each one of these methods is useful to identify the bearing problems. Also, the results proved that the significant variation in the root-mean-square at different rotational speed.

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Analyses of flexural-torsional buckling of rolling H-section steel mono-overhanging beam

A study on flexural-torsional buckling of rolling H-section Steel mono-overhanging beam under uniform load is carried out.It assumes that when the control section of mono-overhanging Beam under uniform load is on the simply supported part,it can be simplified as a simply supported beam under uniform load and a concentrated couple.This paper has derived the formula of critical moment of simply supported beam under uniform load and a concentrated couple by using energy method,and compared the results by ANSYS finite element analysis,and the proposed formula is accurate enough.

Through the check and estimate about some hyperbolic humpback bridges along main highways in Hunan Province,the article introduces the main flaws of hyperbolic humpback bridges,and the reasons that cause them,then addresses some practicable measures of reinforcement reconstruction.

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The electrostatic potential of an infinite array of rectangular cylinders

Electrostatically charged cylinders are useful in precipitators, filters, transmission lines, and optical devices. Studies of infinite arrays of such cylinders are helpful as the limiting cases of the finite arrays. The method of field matching has been applied with success to square cylinders and is extended in this study to treat cylinders of rectangular cross section. The analysis requires the simultaneous solution of two infinite systems of equations. The potential near the charged cylinders is developed as is the capacitance of the cylinders. A number of experimental and theoretical results from other methods are employed in checking the capacitance from field matching. Some ways of applying the method to other problems are mentioned. >

In this paper, we study the polynomial stabilization for a system of magnetoelastic plates. Linear and nonlinear models are considered. The polynomial stability is obtained by means of a new multiplier given by a first-order hyperbolic problem.

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Improved Zero-crossing Method for Power System Frequency Estimation*

Fast and accurate frequency estimation is crucial for power system control, protection and monitoring. This paper proposed an improved zero-crossing method based on weighted multi-level set for frequency estimation with one and half cycle. The proposed method first uses multi-level set, i.e., different thresholds to calculate initial frequencies, then, an optimization process to calculate the weights of the initial frequencies is adopted. Finally, accurate results of power system frequency can be obtained by weighting the initial frequencies. Simulations carried out by Matlab validate the performance of the proposed method as well as the experiment executed on DSP platform.

This paper deals with the study of free transverse vibrations of rectangular plates with an internal line hinge and elastically restrained boundaries. The equations of motion and its associated boundary and transition conditions are rigorously derived using Hamilton’s principle. The governing eigenvalue equation is solved employing a combination of the Ritz method and the Lagrange multipliers method. The deflections of the plate and the Lagrange multipliers are approximated by polynomials as coordinate functions. The developed algorithm allows obtaining approximate solutions for plates with different aspect ratios, boundary conditions, including edges elastically restrained by both translational and rotational springs, and arbitrary locations of the line hinge. Therefore, a unified algorithm has been implemented. Sets of parametric studies are performed and the results are given in graphical and tabular form.

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Study on vibration control of cables with elastic end restraint(II):Experimental verification

The experimental research is conducted to study the axial passive control of cable vibration by setting an elastic end restraint at one support of the cable in the axial direction.The influence of support motion on the natural frequency of cable vibration is presented.Then the damping effect of elastic restraint is verified and the influence of the damping coefficient and the spring stiffness on the damping effect is discussed.Finally the theoretical study [10] is verified to be accurate.

Abstract Wind is one of the fastest-growing renewable sources of electricity. As with most renewables, the economic viability relies on public subsidies. Even among renewables, the economic evaluation of wind projects is particularly challenging due to the unpredictability of the energy source, wind, and the high sensitivity of the project profitability to changes in a number of parameters. This makes the uncertainty analysis an important topic of research in the wind power sector. This study presents a method of combining two uncertainty analysis methods, sensitivity study and the Monte Carlo method, together with a technical and economic model of a wind farm, in an effort to improve the understanding of the practical effects of the uncertainties, and how they affect the financial risks of wind projects.

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An equations of motion approach for open shell systems

A straightforward scheme is developed for extending the equations of motion formalism to systems with simple open shell ground states. Equations for open shell random phase approximation (RPA) are given for the cases of one electron outside of a closed shell in a nondegenerate molecular orbital and for the triplet ground state with two electrons outside of a closed shell in degenerate molecular orbitals. Applications to other open shells and extension of the open shell EOM to higher orders are both straightforward. Results for the open shell RPA for lithium atom and oxygen molecule are given.

Abstract: Road profile and the technical condition of the suspension affect a large measure of comfort, road safety and endurance. This paper contains the theoretical study results of the offroad vehicle vibration when running on a bumpy section of road. For this purpose has been developed mechanical model of tire-suspension -self supporting bodyshell system with five degrees of freedom. The bodyshell was approximated by a flat plate, suspension and tires were modelled by four mass-damper-spring system attached to the four corners of the plate; the tire mass together with a mass suspension is concentrated at a single point. Vertical vibration displacement, velocity and acceleration of the body were determined using Matlab. Key words: vehicle vibration, vehicle mechanical modelling, road deformation.

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Ride performance analysis of half-car model for semi-active system using RMS as performance criteria

The work aims to study the root mean square (RMS) responses to acceleration input for four state variables: the ms vertical acceleration, the ms pitch angular acceleration and the front and rear deflections of the suspensions. A half-car two degree-of-freedom model of semi-active control scheme is analyzed and compared with the conventional passive suspension system. Frequency response of the transfer function for the heave, pitch of the sprung mass and suspension deflections are initially compared and then mean square analysis is utilized to see the effect of semi-active scheme. Results indicate that significant improvements were achieved in the sprung mass heave and pitch responses using semi-active control scheme. However results for the rear and front suspension deflection show that there are limiting values of damping coefficient beyond which, the semi-active scheme becomes disadvantageous than the passive system.

The method for equivalent static wind loads applicable to multi-responses is proposed in this paper. A modified load-response-correlation (LRC) method corresponding to a particular peak response is presented, and the similarity algorithm implemented to the group response is described. The main idea of the algorithm is that two responses can be put into one group if the value of one response is close to that of the other response, when the structure is subjected to equivalent static wind loads aiming at the other response. Based on the modified LRC, the grouping response method is put forward to construct equivalent static wind loading. This technique can simultaneously reproduce peak responses for some grouped responses.

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Improved reflectivity of platinum/carbon multilayers for X-ray mirrors by carbon doping into platinum layer

Abstract We present a study of improving the X-ray reflectivity of platinum/carbon multilayers for X-ray mirrors. The X-ray reflectivity of the multilayers depends entirely on the interface quality. Here we show that carbon doping into the platinum layer limits crystallization during deposition and thus reduces the interface roughness. Platinum/carbon and carbon-doped platinum/carbon multilayers were deposited on a silicon (100) substrate by DC magnetron sputtering. The X-ray reflectivity of the multilayers was measured by grazing incidence X-ray reflectometry with a copper K α1 source. We found that the reflectivity increases with the carbon concentration and that an improvement of about 10% in the reflectivity could be expected.

Abstract This research is focused on the effects of nonlinear terms on the dynamical behavior of graphene reinforced laminated composite plates. Firstly, the governing equations of the graphene reinforced composite thin plate subjected to transverse excitations are derived by using the Hamilton's principle and the von Karman deformation theory. Then numerical method is applied to investigate the nonlinear behaviors of graphene reinforced composite plates. Bifurcation diagram, waveform and phase portrait are demonstrated to analyze the nonlinear dynamics of the graphene reinforced laminated composite plates. Furthermore, the effects of nonlinear terms on the dynamical behavior are discussed in detail, where both the stronger and weaker nonlinear characteristics of lower modes of the plate are presented. Moreover, some interesting phenomena are obtained in numerical simulation.

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Proteins at surfaces studied with the surface force technique

Some results obtained by using the interferometric surface force technique for studying the interactions between adsorbed protein layers and between such layers and surfaces are presented. We have ...

Based on the classical theory of thin plate and Biot theory, a precise model of the transverse vibrations of a thin rectangular porous plate is proposed. The first order differential equations of the porous plate are derived in the frequency domain. By considering the coupling effect between the solid phase and the fluid phase and without any hypothesis for the fluid displacement, the model presented here is rigorous and close to the real materials. Owing to the use of extended homogeneous capacity precision integration method and precise element method, the model can be applied in higher frequency range than pure numerical methods. This model also easily adapts to various boundary conditions. Numerical results are given for two different porous plates under different excitations and boundary conditions.

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Joint And Muscle Forces During Clenching

The masticatory system is highly redundant. Therefore, complete knowledge about the activation patterns of the chewing muscles belonging to a specific resultant bite force can only be gained either by simultaneous force- and EMG-measurement or with the help of optimization strategies. In this study, such EMG and force measurements were carried out with 10 test persons and the results compared to those computed with several objective functions. The results show an increase of the joint forces with an increase of the horizontal component of the resultant bite force. The test persons seem to favor energy minimization as control mechanism.

This paper computed No.17 coupler yoke' stress intensity factors based on 1/4 displacement method of finite element method,calculated the crack propagation life of No.17 coupler yoke using Paris formula based on AAR spectrum,and given analysis and evaluation for the result.

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Potential of Finite Element Analysis for Cephalometric Investigation

In view of concerns relating to the validity of traditional cephalometric appraisals, we undertook this study to use a potentially powerful method, finite element analysis, to compare cephalometric changes between two samples (subjects with and without orthodontic treatment). The derived data show varying sample contrasts depending on the particular finite element array included in the analysis. Thus, although finite element analysis facilitates rigorous morphometric analysis, further investigation is required before it can be applied universally in cephalometric studies.

ABSTRACTThis paper aims to develop, assess, and numerically implement analytical models for the newly introduced Quintuple Friction Pendulum Isolator (QFPI) which can identically capture its real e...

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Polynomial stabilization of magnetoelastic plates

In this paper, we study the polynomial stabilization for a system of magnetoelastic plates. Linear and nonlinear models are considered. The polynomial stability is obtained by means of a new multiplier given by a first-order hyperbolic problem.

Morphological changes of ultrahigh-molecular-weight polyethylene reactor powders were studied using scanning electron microscopy after their compaction and monolith production. The optimum conditions (pressure and temperature) for the compaction and monolith production of the reactor powders were determined.

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Resonant vibrations of free cylinders and disks

A complete solution is obtained for nonaxisymmetric resonant vibrations of a free cylinder or disk involving infinite sums. For axisymmetric longitudinal vibrations an alternative to previous solutions is included. In principle, the solutions satisfy exactly the stress‐free boundary conditions , in contrast to the approximate bending‐mode solutions due to Pickett or approximate solutions based on a small diameter/length ratio and small shearing stresses at the ends.Subject Classification: 40.26, 40.24; 20.40.

SUMMARY ::: ::: In this paper six distribution-free (nonparametric) stereological methods for the solution of Wicksell's corpuscle problem—i.e. the determination of the distribution of diameters of spheres embedded in an opaque specimen from the diameters of their profiles on plane sections—are compared as regards their numerical stability, sensitivity to underlying distributions and certain error criteria. The study is based on the results of simulation studies for several types of distribution (one-point, normal, exponential, logarithmic normal) of sphere diameters. Recommendations are suggested for the choice of methods, sample size and the optimal number of classes for grouping sample data.

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Coupled instabilities for a thick elastic plate under thrust

For a thick incompressible hyperelastic plate under biaxial thrust, flexural and constitutive (homogeneous) instabilities are considered. In the present study their interaction (coupling) is discussed, when the critical conditions coincide for both kinds of instabilities. With the help of branching theory, especially the Fredholm Alternative theorem, the interactive post-critical equilibrium configurations are defined.

This paper computed No.17 coupler yoke' stress intensity factors based on 1/4 displacement method of finite element method,calculated the crack propagation life of No.17 coupler yoke using Paris formula based on AAR spectrum,and given analysis and evaluation for the result.

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Approximate Green's functions and a boundary element method for electro-elastic analyses of active materials

Abstract A boundary element method (BEM) for the analysis of two-dimensional, time independent problems of linear electro-elasticity is presented. Emphasis is given to the derivation of representation formulas and fundamental solutions as well as to the construction of an efficient numerical algorithm. The method is particularly suitable for studying the behavior of active materials such as electrostrictive, ferroelectric and piezoelectric ceramics. Two numerical examples with direct impact on the structural safety and reliability of piezoceramics are provided to demonstrate the virtues of the new BEM.

In this paper verification methods for Fredholm integral equations are considered. By these methods the numerical approximation is computed together with mathematically guaranteed error bounds of high quality. The foundations for such numerics is described and then applied to Fredholm integral equations. We conclude by some numerical examples demonstrating the effectiveness of such new numerical schemes.

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A study on free vibration of a ring-stiffened thin circular cylindrical shell with arbitrary boundary conditions

The vibration of ring-stiffened cylinders associated with arbitrary boundary conditions is investigated. Displacements of cylinders can be easily described by trigonometric functions when the cylinders are shear diaphragms supported at both ends. As to other boundary conditions, exponential functions are used and axial factors are introduced. An eighth-order algebraic equation for this axial factor is derived. The physical meaning of the axial factor is studied. Both analytical and numerical studies prove that, when the axial factor is a pure imaginary number, the cylinder appears to have a certain length with shear diaphragm boundary conditions. The effects of shell parameters and hydrostatic pressure on the axial factor are determined in the analysis.

Abstract Degenerate Rayleigh-Schrodinger perturbation theory is treated by expansions in unperturbed eigenfunctions. The results of seventh order perturbation are presented for the cases in which the degeneracy can be totally removed in the first and second orders.

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A computation of the frequency dependent dielectric function for energetic materials

A theory of excitation of a solid system by a shock is developed and is implemented using first order time-dependent perturbation theory. This allows one to study excitation by both the longitudinal fields generated in a shock and also the transverse radiation field from the accelerating atoms. This is argued to be the mechanism by which shock energy (initially translational) is converted into lattice vibrations, and finally as to how these vibrations are converted into molecular vibrations, electronic excitations or even collective excitations. Some specific examples are seen for the time harmonic transverse field portion of the problem.

Abstract This research is focused on the effects of nonlinear terms on the dynamical behavior of graphene reinforced laminated composite plates. Firstly, the governing equations of the graphene reinforced composite thin plate subjected to transverse excitations are derived by using the Hamilton's principle and the von Karman deformation theory. Then numerical method is applied to investigate the nonlinear behaviors of graphene reinforced composite plates. Bifurcation diagram, waveform and phase portrait are demonstrated to analyze the nonlinear dynamics of the graphene reinforced laminated composite plates. Furthermore, the effects of nonlinear terms on the dynamical behavior are discussed in detail, where both the stronger and weaker nonlinear characteristics of lower modes of the plate are presented. Moreover, some interesting phenomena are obtained in numerical simulation.

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Development of Vibration Isolation Mounts of a Vehicle Using Static and Dynamic Analysis

Abstract In automotive industry, rubber mounts are widely used to cushion the loads and isolate vibration in passenger vehicle compartments. In this study an engine rubber mount and strut bushing are analysed. The static and dynamic characteristics of the rubber specimen as well as the viscoelastic and hyperelastic properties are obtained by static and dynamic testing. The material properties coefficients in the finite element analysis have been implemented accordingly to the test data. The dynamic and static characteristics of the strut bushing and the engine mount are predicted with finite element analysis. The solutions show satisfactory agreement between predicted and experimental results. According to the authors, this work on the development of vibration isolation mounts using physical tests and simulations for verification of the final product, and providing the static and dynamic design factors represents pioneer work in open literature.

Discontinuous solutions or interfaces are common in nature, for examples, shock waves or material interfaces. However, their numerical computation is difficult by the feature of discontinuities. In this paper, we summarize the numerical approaches for discontinuities and interfaces appearing mostly in the system of hyperbolic conservation laws, and explain various numerical methods for them. We explain two numerical approaches to handle discontinuities in the solution: shock capturing and shock tracking, and illustrate their underlying algorithms and mathematical problems. The front tracking method is explained in details and the level set method is outlined briefly. The several applications of front tracking are illustrated, and the research issues in this field are discussed.

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L'anneau $$\mathbb{Z} [\sqrt {14} ]$$ et l'algorithme Euclidien

The aim of this note is to study the ring\(\mathbb{Z} [\sqrt {14} ]\) and in particular the question whether it is Euclidean or not. The following results are obtained: ::: ::: 1) ::: ::: The couples of elements of\(\mathbb{Z} [\sqrt {14} ]\) which are not Euclidean with respect to the absolute value of the norm are determined. ::: ::: ::: ::: ::: 2) ::: ::: An Euclidean algorithm for\(\mathbb{Z} [\sqrt {14} ]\) is constructed under suitable assumptions (Hypothese 4.1).

There are several formulations for the beam element in the large deformation and displacement problem. Recently, Absolute Nodal Coordinate Formulation (ANCF) is studied for such problems. In this formulation, the mass matrix and the stiffness matrix are described as simple equations, even in the case of the large deformation and displacement problem. However, degree of freedom of the beam element of ANCF increases from conventional finite element method, since the beam element is formulated by 8 absolute nodal coordinates. In this paper, the authors propose a formulation and an assembling method of the beam element formulated by 6 absolute nodal coordinates considering the calculation efficiency. In this method, the number of nodal coordinates of the assembling point of beam elements is same as nonlinear finite element method. The effect of the proposed method is verified by the numerical simulations.

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Vibration of a Free Gyroscope on a Non-Uniform Elastic Shaft

This paper is a sequel to a previous work in which the vibrations were considered of a gyroscope mounted on a uniform elastic shaft within two rigid gimbals. The theory has now been extended to include a more general practical arrangement in which the shaft is non-uniform. Experimental results have also been obtained which confirm the general conclusions of the theory.

Abstract This paper presents the results of experimental study of gas turbine rotor of Air craft, Marine, wind turbine rotor etc. The natural frequency of gas turbine rotor using Holzer’s method same are compared with the results that are obtained through a well known software based approach of FFT Analyzer. Rotors employed for transmitting motion are manufacturing using mild steel as it offers better stiffness and economical conditions under damping conditions. Mild steel as it resists tortional loads and bending loads more efficiency are more effectively. In this paper natural frequency of the gas turbine rotor predicted according to numerical results will be compared with experiential results.

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Experimental study on dynamic characteristics of a high-speed rolling ball bearing support system with rubber rings

The study presented in this paper experimentally studied the dynamic characteristics of the high-speed rolling ball bearing support system with rubber rings in the filament winding head of rotating machinery. First, a test-bed was established. Then, the amplitude-frequency relationship of the support system with three kinds different compression of rubber rings was measured and their relationship with respect to the structure of the support system with rubber rings was established. In particular, the equivalent stiffness and damping of the support system were calculated. This relationship is conducive to the optimization of design and vibration control of this kind of machinery.

In this article, we derive error estimates for the Galerkin approximation of a general linear second order hyperbolic equation. The results can be applied to a variety of cases, for example, vibrating systems of linked elastic bodies. The results generalize the work of Baker [1] and also allow for viscous type damping. Splitting the proofs for the semi-discrete and fully discrete cases not only simplifies the proofs but less restrictive regularity assumptions are required.

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Equations of Motion Formulation of a Pendulum Containing N-point Masses

This paper presents a general formulation of equations of motion of a pendulum with n point mass by use of two different methods. The first one is obtained by using Lagrange Mechanics and mathematical induction(inspection), and the second one is derived by defining a vector. Today, these equations can be obtained by employing numerous programs; however, this study gives a very compact form of these equations that is more efficient than solving Euler-Lagrange Equations for every pendulum with more complex structures than simple or double pendulum.

A new modeling method based on sample data is described in this paper,through physics and sample date analysis on displacement vs.voltage characteristics of x-y plane of cylindrical piezoelectric scanner used in scanning probe microscope(SPM).Through sample data statistical analysis,and considering the error factors such as scan speed,scan angle,nonlinearity and coupling,a model represented by a binomial plus some error expressions is constructed.A nonlinearity correction expression based on the model is deduced.With the software Matlab this nonlinearity correction is simulated.The result of simulation indicates that it can eliminate the errors effectively.The ascendency of the method is that there are no polarization mechanism analysis and fewer number of model parameters.The method is practical applied to engineering.

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Study and Optimization of the Web Print Fold Mechanism

A study of the factors which affect the fold kinematic activities has been presented,through the design analysis,the sensitivity of acceleration vs.design was obtained.According to the sensitivity,the lengths of linkage and crank were determined as design variables.The optimization technique was applied to an ADAMS Model so as to minimize the value of acceleration.The result showed that the value of jerk was also improved while the value of acceleration was optimizing.It will improve the vibration properties and be the foundation of dynamics simulation later on.

Abstract In this paper, basic and more realistic dynamic cobweb models are developed in terms of conformable fractional derivatives. The general solutions and stability criteria for the proposed models are given. Moreover, the developed models are illustrated with examples on several time scales.

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An Equilibrium Model for the Nta Complexation of Metal Ions in Natural Waters

Abstract The equilibrium distribution of NTA among several naturally occurring metal ions has been calculated from previously reported complex ion formation constants. Competition among chelators for the same metals is deduced by introducing the additional model ligands cysteine and citrate to the system. The fraction of NTA, and in the mixed system the fractions of each ligand, bound to each metal at 25°C and pH 7.4 are reported. It is concluded that the most important NTA complexes are those of copper and zinc, and because of their predominance and known biological properties there should be no new toxicological problems arising because of chelation of metal ions already present in the environment as a result of the substitution of NTA for phosphates in detergents.

This paper deals with the study of free transverse vibrations of rectangular plates with an internal line hinge and elastically restrained boundaries. The equations of motion and its associated boundary and transition conditions are rigorously derived using Hamilton’s principle. The governing eigenvalue equation is solved employing a combination of the Ritz method and the Lagrange multipliers method. The deflections of the plate and the Lagrange multipliers are approximated by polynomials as coordinate functions. The developed algorithm allows obtaining approximate solutions for plates with different aspect ratios, boundary conditions, including edges elastically restrained by both translational and rotational springs, and arbitrary locations of the line hinge. Therefore, a unified algorithm has been implemented. Sets of parametric studies are performed and the results are given in graphical and tabular form.

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Dynamic Response of Forum Gdansk Structure due to Rail Traffic

Abstract This paper presents the study of the impact of vibration induced by the movement of the railway rolling stock on the Forum Gdańsk structure. This object is currently under construction and is located over the railway tracks in the vicinity of the Gdańsk Głowny and Gdańsk Środmieście railway stations. The analysis covers the influence of vibrations on the structure itself and on the people within. The in situ measurements on existing parts of the structure allow us to determine environmental excitations used for validation and verification of the derived FEM model. The numerical calculations made the estimates of the vibration amplitudes propagating throughout the whole structure possible.

The article discusses the question of development of software for automated design of road wooden bridge spans. The adaptive pattern of elastic load distribution calculation based on obtained loading theorem providing optimal geometry elements choice is developed. It is given a comparison of the measured real spans deflection with the results of calculating using two methods.

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Linear simulations of acoustic wave propagation in a sun-like spherical shell

Helioseismology is the study of the variations in the internal structure and properties of the dynamics of the sun from measurements of its surface oscillations. We are interested in validating and determining the efficacy of the helioseismic measurement procedure. To this end, we simulate acoustic wave propagation in a solar-like spherical shell that extends from 0.2R to about 1.0004 R, where R is the radius of the sun. In order to render the calculation tractable, wave propagation is treated as a linear phenomenon. In this article, I will discuss the difficulties that are consequent to the assumption of linearity and the methods to resolve them thereof.

The paper presents research results referring to the development of a non-invasive method of assessment of the power transformer core technical condition based on the analysis of the mechanical vibrations registered. It characterizes the power object under study, the measuring system used and the developed methodology of assessment of the core pressing degree using the vibroacoustic method. The original results of the time–frequency analysis of the vibroacoustic signals presented in the paper were obtained during switching on a real 800 kVA dry type power transformer in laboratory conditions. The analysis of the signals registered was carried out for three states of its operation: the core pressed by the manufacturer, the core with loose screws fixing the upper yoke and the core with separated upper yoke beams.

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Modal analysis of naval gun bracket based on ANSYS

Aiming at that naval gun bracket is a symmetrical box-style structure and made of stiffeners,the finite element model of bracket is established based on the structural analysis software ANSYS.The static stress and deflection were analyzed by an auxiliary rigid-body model.The natural frequency and mode of naval gun bracket were investigated using modal analysis theory.The dynamic response of bracket under recoil force excitation was simulated.The research work gives theoretic support to the structure design and optimization of naval gun bracket.

In the oil production and thermal recovery in the application of oil and gas field, well of curves are regarded as the crooked canal(namely not only the canal has horizontal section but also vertical section), it instead the horizontal well before. Thus establishmented the new elbow well model, the solution of the model not only suitable for theoretical study but also easy to calculate in practical production. This article considered the problem of indeterminate percolation of spherical symmetry infinite domain described by the initial boundary value problem of the system of partial differential equation and obtained the point-source accurate solution when research on the problem of indeterminate percolation for double porosity medium. Abtained the accurate solution about mathematical model of line source from appling the point-source accurate solution, and applied the results to mathematical model of well of curves, obtained the integral expression of it’s accurate solution.

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NONAXISYMMETRIC VIBRATIONS OF CYLINDRICAL SHELLS PARTIALLY FILLED WITH LIQUID

An algorithm is given for calculating frequencies and natural vibration modes of shells described in the title, taking into account the wave motion of the free surface. Boundary conditions corresponding to the elastic fastening of the cylinder's end rims are assumed. The solution is based on general integral equations of vibrations for a shell without liquid and on the method for solving Fredholm's equations of second kind with degenerate kernel. Numerical results are given for shells freely supported or rigidly clamped at both ends, and shells with one end being free and the other being clamped. Predictions are compared with experimental data.

We study the initial boundary value problem for the nonlinear viscoelastic wave equation with strong damping term and dispersive term. By introducing a family of potential wells we not only obtain the invariant sets, but also prove the existence and nonexistence of global weak solution under some conditions with low initial energy. Furthermore, we establish a blow-up result for certain solutions with arbitrary positive initial energy (high energy case)

yue_Hant

Simulation of Motions of Berthed Vessels - Simplified Simulation Model

A simulation model for analyses of motions of berted vessels is described. The simulation is performed as a time domain analyses.

This paper presents a suitable solution of studying methods on BRBs’ critical load with finite element software．The effects of the relevant factors on the BRBs’ ultimate bearing capacity are investigated, and some practical suggestions for the design and production are provided．

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Stability Analysis of Normal DGP Brane-world Model with Agegraphic Dark Energy

The aim of this work is to apply the dynamical system approach to study the linear dynamics of normal DGP brane-world model with agegraphic dark energy as the dark energy component. The stability analysis of the model will be investigated and phase plane portrait will be shown. The nature of critical points will be analyzed by evaluating the eigenvalues of linearized Jacobi matrix. Also, statefinder diagnostic procedure will be applied to compare deviation from {\Lambda}CDM model. One of the most interesting results of this work is the great alleviation of the coincidence problem.

The structure of GMA is introduced. Static displacement-force model and magnetism-machine coupling model for helping understand the magnetostriction and establishes simulation model are given. Simulation result shows that response time of machine part is slowness. It brings some disbennifit affection if minish damp. For example,exceed quantity and undulation will argument. It is important to ameliorate dynamic characteristic of the system to append a reasonable adjustor.

kor_Hang

Buckling strength of deformable monosymmetric I-beams

Abstract An energy method of analysis is developed for studying the inelastic distortional buckling of welded monosymmetric I-beams with slender webs. The method uses the Cambridge model of residual stresses. An eigenproblem of order four is developed, and the microcomputer solution of the problem is very rapid. Following studies of the accuracy of the buckling solutions, the method is used to demonstrate the interaction between distortion and yielding of a monosymmetric I-beam with a slender web.

The article discusses the question of development of software for automated design of road wooden bridge spans. The adaptive pattern of elastic load distribution calculation based on obtained loading theorem providing optimal geometry elements choice is developed. It is given a comparison of the measured real spans deflection with the results of calculating using two methods.

eng_Latn

How can I determine a spring stiffness and geometry for a formula student car?

How is the formula for the stiffness of a spring determined?

Can I get 80% marks in physics and chemistry CBSE class 12 boards just by studying past year questions and chapterwise solutions?

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How do you determine the formula of the stiffness of a spring?

How is the formula for the stiffness of a spring determined?

Can I get 80% marks in physics and chemistry CBSE class 12 boards just by studying past year questions and chapterwise solutions?

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Bone Marrow Matches Hard for Multiracial

Luke Do was a lively 18-month-old awaiting the birth of his first sibling when he was diagnosed with a rare form of leukemia. The hopes of his parents, both doctors in San Jose, Calif., immediately turned to a bone marrow transplant, but they soon learned some distressing news &#151; Luke's ethnic heritage made him a tough match.

Your month of birth may influence your risk of multiple sclerosis, says a study published online in the British Medical Journal. The study concluded that people in the northern

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SENSITIVITY OF HEAVY RAINFALL TO LOCAL VEGETATION TYPES IN SOUTHEASTERN HU'NAN

A modeling study of land surface process impacts on inland behavior of Typhoon Rananim (2004)

No Relationships Between the Within-Subjects’ Variability of Pain Intensity Reports and Variability of Other Bodily Sensations Reports

yue_Hant

The mission , designed to deploy a satellite to study the approaching Halley 's Comet and to inaugurate the Teacher in Space Project , was delayed numerous times due to bad weather and technical glitches .

The mission was designed to deploy a satellite to study the approaching Halley 's Comet and to inaugurate the Teacher in Space Project . It was delayed several times due to bad weather and technical glitches .

Rosa quickly decayed over the mountains of Mexico , and its cloud shield rapidly accelerated northward through the Plains and Mississippi Valley , moistening the atmosphere enough in Texas ahead of a slow moving occluded cyclone to help set the stage for a significant flood event in east Texas on the October 17 .

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Massive Hurricane Frances Smothers Florida

Hurricane Frances smothered eastern Florida on Sunday with drenching rains and fierce winds that ripped away roofs, trees and boat moorings and cut power to 1.3 million homes and businesses.

One of Earth's largest-ever megafloods broke apart a strip of land connecting what is now Britain and France, permanently separating them, a new study says.

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Massive Hurricane Frances Smothers Florida

COCOA, Fla. - Hurricane Frances smothered eastern Florida on Sunday with drenching rains and fierce winds that ripped away roofs, trees and boat moorings and cut power to 1.3 million homes and businesses.

One of Earth's largest-ever megafloods broke apart a strip of land connecting what is now Britain and France, permanently separating them, a new study says.

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Hurricane Survivors Wait in Line for Aid

PUNTA GORDA, Fla. - Driven from splintered trailers, roofless condos and powerless suburban homes, Hurricane Charley's hungry victims sweated through long lines Monday to find food, showers and drinking water three days after the storm left their lives in shambles...

Staying uninvolved while interviewing participants for a study about the effect of food shortages on H.I.V. treatment is often difficult, one researcher finds.

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Spain bombs 'follow Eta warning'

Bombs explode in separate Spanish towns after a warning in the name of the armed Basque separatist group, Eta.

California is lagging in key areas of readiness for a bioterrorism attack, according to a national study released yesterday. The state fell short on five of the 10 indicators

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Houston's Explosive Growth Amid Disregard Of Flood Preparedness

Neena Satija is an investigative reporter for the Texas Tribune, reporting on the flooding in Houston. She led a 2016 investigation into the Houston area's lack of preparation for catastrophic flooding events.

New findings based on the Sept. 11 disaster are prompting emergency workers and architects to rethink evacuation plans and building designs. A study published this week debunks the notion that people are likely to respond quickly to building alarms. NPR's Alix Spiegel reports.

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Florida - Hurricane Insurance

Phillip Davis reports on the political battle surrounding rising hurricane insurance rates in Florida. Florida insurers have used a scientific model they commissioned to argue that global warming means that Hurricane strength will continue to increase in the coming years, thus the need for rate increases. State meteorologists are not convinced. But efforts to get money appropriated for an independent state study have been killed by the insurance lobby.

Towns across the mountains of east Tennessee and North Carolina suffer severe flood damage. Hurricane Frances had already saturated the ground in the region, and heavy rains from Ivan sent many rivers over their banks. Hear NPR's Chris Arnold.

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A novel and an effective analytical approach for the LC-MS determination of ethyl glucuronide and ethyl sulfate in urine

A rapid LC-MS/MS method for determination of urinary EtG and application to a cut-off limit study

The Mediatorless Electroanalytical Sensing of Sulfide Utilizing Unmodified Graphitic Electrode Materials

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Sensitive and selective fluorometric determination of DNA by using layered hexagonal nanosheets of a covalent organic framework prepared from p-phenylenediamine and benzene-1,3,5-tricarboxaldehyde

Chemically Delaminated Free-Standing Ultrathin Covalent Organic Nanosheets

Checking for completeness of 24-h urine collection using para-amino benzoic acid not necessary in the Observing Protein and Energy Nutrition study

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Theoretical study of palladium cluster structures on carbonaceous supports

α-d-Glucopyranose Adsorption on a Pd30 Cluster Supported on Boron Nitride Nanotube

Surface of localized pleural plaques quantitated by computed tomography scanning: no relation with cumulative asbestos exposure and no effect on lung function

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Copper status of exposed microorganisms influences susceptibility to metallic nanoparticles

Evaluation of the toxicity of ZnO nanoparticles to Chlorella vulgaris by use of the chiral perturbation approach

Numerical and experimental study of the shielding effectiveness of a metallic enclosure

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SWARM Absolute Scalar Magnetometer accuracy: Analyses and measurement results

The different factors that affect the SWARM optically pumped Absolute Scalar Magnetometer (ASM) accuracy are reviewed and analyzed. An overall precision of less than 45 pT (1 σ) is reported, which is well under the 300 pT specified for global ASM accuracy.

In this work, the feasibility of using agricultural waste of sorghum (AWS) in the removal of methylene blue (MB) colorant was evaluated. The experiments were carried out using fixed-bed column in a continuous system and the breakthrough curves were adjusted to the mathematical models of Adams and Bohart, Yoon and Nelson, Thomas and Doses-Response by programming them in the MATLAB R2007a software. With the realization of this study, the high biosorbent adsorption capacity has been demonstrated, as well as the high operating efficiency in column filled with AWS in the elimination of methylene blue colorant.

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Synthesis of titanium-containing mesoporous molecular sieves with a cubic structure

A titanium-containing mesoporous material with a cubic structure, Ti-MCM-48, is synthesized by a two-stage hydrolysis method using tetraethylorthosilicate and tetrabutylorthotitanate and found to be more active than Ti-MCM-41 in the epoxidation of bulky alkenes using H2O2.

Objective To study the best extracting technology of Compound Taizishen Granule prescription.Methods The total polysaccharides and total saponins were determined by UV spectrophotometer.With the content of total polysaccharides and total saponins as comprehensive indexes,orthogonal test was applied to investigation of the water addition,extraction time,and extraction times for optimizing the best extracting technology.Results The best extracting technology was using 10 times the amount of water,extracting 3 times and 1.5 h per time.Conclusion The extraction technology is safe and effective,which can be used as extraction for Compound Taizishen Granule prescription.

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A highly performed nonenzymatic glucose sensor using surfactant template assisted platinum nanoparticles

In this work, we have successfully developed an enzyme free glucose sensor with highly performed electrodes, which was decorated with surfactant assisted platinum nanoparticles (PtNPs) on rectangular shaped thin Au film electrode. The PtNPs have been used for their outstanding catalytic activity for the redox reaction of H2O2. Diblock copolymer surfactant template was used to deposit platinum nanoparticles on the working and counter electrodes, simultaneously. Optimal potential was investigated and applied for the uniform distribution of PtNPs. The fabricated biosensor showed good electrocatalytic performance in terms of high sensitivity of 0.32 μA/mM, fast response of 5 s, and wide linear range from 0.0625 to 22 mM.

Background and Objective Chemotherapeutic drug treatment outcomes are genetically determined. Polymorphisms in genes encoding phase II drug metabolizing enzyme glutathione-S-transferase (GST) can possibly predict treatment outcomes, and can be of prognostic significance in breast cancer patients. The aim of this study was to determine the role of genetic variations in GST in predicting response to, and toxicity of, anthracycline-based chemotherapy in breast cancer patients. Method Two hundred and seven patients treated with anthracycline-based chemotherapy were genotyped for GSTM1 and GSTT1 deletion polymorphisms, and GSTP1 Ile 105 Val (rs1695), by polymerase chain reaction (PCR)/

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