期刊文献+
共找到2,420篇文章
< 1 2 121 >
每页显示 20 50 100
Highly Accurate Golden Section Search Algorithms and Fictitious Time Integration Method for Solving Nonlinear Eigenvalue Problems
1
作者 Chein-Shan Liu Jian-Hung Shen +1 位作者 Chung-Lun Kuo Yung-Wei Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1317-1335,共19页
This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solve... This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solved from a nonhomogeneous linear system obtained by reducing the number of eigen-equation one less,where one of the nonzero components of the eigenvector is normalized to the unit and moves the column containing that component to the right-hand side as a nonzero input vector.1D and 2D golden section search algorithms are employed to minimize the merit functions to locate real and complex eigenvalues.Simultaneously,the real and complex eigenvectors can be computed very accurately.A simpler approach to the nonlinear eigenvalue problems is proposed,which implements a normalization condition for the uniqueness of the eigenvector into the eigenequation directly.The real eigenvalues can be computed by the fictitious time integration method(FTIM),which saves computational costs compared to the one-dimensional golden section search algorithm(1D GSSA).The simpler method is also combined with the Newton iterationmethod,which is convergent very fast.All the proposed methods are easily programmed to compute the eigenvalue and eigenvector with high accuracy and efficiency. 展开更多
关键词 Nonlinear eigenvalue problem quadratic eigenvalue problem two new merit functions golden section search algorithm fictitious time integration method
下载PDF
CAUCHY TYPE INTEGRALS AND A BOUNDARY VALUE PROBLEM IN A COMPLEX CLIFFORD ANALYSIS
2
作者 曹南斌 李尊凤 +1 位作者 杨贺菊 乔玉英 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期369-385,共17页
Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quan... Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quantum mechanics and value problems.In this paper,we first give the definition of a quasi-Cauchy type integral in complex Clifford analysis,and get the Plemelj formula for it.Second,we discuss the H?lder continuity for the Cauchy-type integral operators with values in a complex Clifford algebra.Finally,we prove the existence of solutions for a class of linear boundary value problems and give the integral representation for the solution. 展开更多
关键词 Clifford analysis Cauchy type integral Plemelj formula Holder continuous boundary value problems
下载PDF
Element nodal computation-based radial integration BEM for non-homogeneous problems 被引量:1
3
作者 Hai-Feng Peng Kai Yang Xiao-Wei Gao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第3期429-436,共8页
This paper presents a new strategy of using the radial integration boundary element method (RIBEM) to solve non-homogeneous heat conduction and thermoelasticity problems. In the method, the evaluation of the radial ... This paper presents a new strategy of using the radial integration boundary element method (RIBEM) to solve non-homogeneous heat conduction and thermoelasticity problems. In the method, the evaluation of the radial in-tegral which is used to transform domain integrals to equivalent boundary integrals is carried out on the basis of elemental nodes. As a result, the computational time spent in evaluating domain integrals can be saved considerably in comparison with the conventional RIBEM. Three numerical examples are given to demonstrate the correctness and computational efficiency of the proposed approach. 展开更多
关键词 Radial integral Boundary element method Non-homogeneous problem Heat conduction Thermoe-lasticity
下载PDF
Precise integration method for solving singular perturbation problems 被引量:1
4
作者 富明慧 张文志 S.V.SHESHENIN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第11期1463-1472,共10页
This paper presents a precise method for solving singularly perturbed boundary-value problems with the boundary layer at one end. The method divides the interval evenly and gives a set of algebraic equations in a matr... This paper presents a precise method for solving singularly perturbed boundary-value problems with the boundary layer at one end. The method divides the interval evenly and gives a set of algebraic equations in a matrix form by the precise integration relationship of each segment. Substituting the boundary conditions into the algebraic equations, the coefficient matrix can be transformed to the block tridiagonal matrix. Considering the nature of the problem, an efficient reduction method is given for solving singular perturbation problems. Since the precise integration relationship introduces no discrete error in the discrete process, the present method has high precision. Numerical examples show the validity of the present method. 展开更多
关键词 singular perturbation problem first-order ordinary differential equation two-point boundary-value problem precise integration method reduction method
下载PDF
A new simple method of implicit time integration for dynamic problems of engineering structures 被引量:1
5
作者 Jun Zhou Youhe Zhou 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第1期91-99,共9页
This paper presents a new simple method of implicit time integration with two control parameters for solving initial-value problems of dynamics such that its accuracy is at least of order two along with the conditiona... This paper presents a new simple method of implicit time integration with two control parameters for solving initial-value problems of dynamics such that its accuracy is at least of order two along with the conditional and unconditional stability regions of the parameters. When the control parameters in the method are optimally taken in their regions, the accuracy may be improved to reach of order three. It is found that the new scheme can achieve lower numerical amplitude dissipation and period dispersion than some of the existing methods, e.g. the Newmark method and Zhai's approach, when the same time step size is used. The region of time step dependent on the parameters in the new scheme is explicitly obtained. Finally, some examples of dynamic problems are given to show the accuracy and efficiency of the proposed scheme applied in dynamic systems. 展开更多
关键词 Initial-value problems Time integration Implicit method Higher accuracy Time step and stability
下载PDF
Precise integration method for a class of singular two-point boundary value problems 被引量:2
6
作者 Wen-Zhi Zhang Pei-Yan Huang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第2期233-240,共8页
In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the met... In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the method of variable coefficient dimensional expanding,the non-homogeneous ordinary differential equations(ODEs) are transformed into homogeneous ODEs.Then the interval is divided evenly,and the transfer matrix in every subinterval is worked out using the high order multiple perturbation method,and a set of algebraic equations is given in the form of matrix by the precise integration relation for each segment,which is worked out by the reduction method.Finally numerical examples are elaboratedd to validate the present method. 展开更多
关键词 Singular two point boundary value problem Precise integration method High order multiple perturbation method Reduction method
下载PDF
Consistency and Stability Issues in the Numerical Integration of the First and Second Order Initial Value Problem 被引量:1
7
作者 Isaac Fried 《Applied Mathematics》 2019年第8期676-690,共15页
In this note we consider some basic, yet unusual, issues pertaining to the accuracy and stability of numerical integration methods to follow the solution of first order and second order initial value problems (IVP). I... In this note we consider some basic, yet unusual, issues pertaining to the accuracy and stability of numerical integration methods to follow the solution of first order and second order initial value problems (IVP). Included are remarks on multiple solutions, multi-step methods, effect of initial value perturbations, as well as slowing and advancing the computed motion in second order problems. 展开更多
关键词 INITIAL Value problems Numerical integration CONSISTENCY STABILITY Multiple Solutions Sensitivity to INITIAL Conditions Slowing and Advancing the COMPUTED Motion
下载PDF
Integration of axiomatic design and theory of inventive problem solving for conceptual design 被引量:1
8
作者 田启华 《Journal of Chongqing University》 CAS 2009年第3期209-216,共8页
Axiomatic design (AD) and theory of inventive problem solving (TRIZ) are widely used in conceptual design. Both of them have limitations, however. We presented an integrated model of these two methods to increase the ... Axiomatic design (AD) and theory of inventive problem solving (TRIZ) are widely used in conceptual design. Both of them have limitations, however. We presented an integrated model of these two methods to increase the efficiency and quality of the problem solving process for conceptual design. AD is used for systematically defining and structuring a problem into a hierarchy. Sometimes, the design matrix is coupled in AD which indicates the functional requirements are coupled. TRIZ separation principles can be used to separate non-independent design parameters, which provide innovative solutions at each hierarchical level. We applied the integrated model to the heating and drying equipment of bitumen reproduction device. The result verifies that the integrated model can work very well in conceptual design. 展开更多
关键词 conceptual design axiomatic design theory of inventive problem solving integrated model drying cylinder
下载PDF
Volterra Integral Equations and Some Nonlinear Integral Equations with Variable Limit of Integration as Generalized Moment Problems 被引量:1
9
作者 Maria B. Pintarelli 《Journal of Mathematics and System Science》 2015年第1期32-38,共7页
In this paper we will see that, under certain conditions, the techniques of generalized moment problem will apply to numerically solve an Volterra integral equation of first kind or second kind. Volterra integral equa... In this paper we will see that, under certain conditions, the techniques of generalized moment problem will apply to numerically solve an Volterra integral equation of first kind or second kind. Volterra integral equation is transformed into a one-dimensional generalized moment problem, and shall apply the moment problem techniques to find a numerical approximation of the solution. Specifically you will see that solving the Volterra integral equation of first kind f(t) = {a^t K(t, s)x(s)ds a ≤ t ≤ b or solve the Volterra integral equation of the second kind x(t) =f(t)+{a^t K(t,s)x(s)ds a ≤ t ≤ b is equivalent to solving a generalized moment problem of the form un = {a^b gn(s)x(s)ds n = 0,1,2… This shall apply for to find the solution of an integrodifferential equation of the form x'(t) = f(t) + {a^t K(t,s)x(s)ds for a ≤ t ≤ b and x(a) = a0 Also considering the nonlinear integral equation: f(x)= {fa^x y(x-t)y(t)dt This integral equation is transformed a two-dimensional generalized moment problem. In all cases, we will find an approximated solution and bounds for the error of the estimated solution using the techniques ofgeneralized moment problem. 展开更多
关键词 Generalized moment problems solution stability Volterra integral equations nonlinear integral equations.
下载PDF
An Eight Component Integrable Hamiltonian Hierarchy from a Reduced Seventh-Order Matrix Spectral Problem
10
作者 Savitha Muthanna Wen-Xiu Ma 《Journal of Applied Mathematics and Physics》 2024年第6期2102-2111,共10页
We present an eight component integrable Hamiltonian hierarchy, based on a reduced seventh order matrix spectral problem, with the aim of aiding the study and classification of multicomponent integrable models and the... We present an eight component integrable Hamiltonian hierarchy, based on a reduced seventh order matrix spectral problem, with the aim of aiding the study and classification of multicomponent integrable models and their underlying mathematical structures. The zero-curvature formulation is the tool to construct a recursion operator from the spatial matrix problem. The second and third set of integrable equations present integrable nonlinear Schrödinger and modified Korteweg-de Vries type equations, respectively. The trace identity is used to construct Hamiltonian structures, and the first three Hamiltonian functionals so generated are computed. 展开更多
关键词 Matrix Spectral problem Zero Curvature Equation Lax Pair integrable Hierarchy NLS Equations mKdV Equations Hamiltonian Structure Lie Bracke
下载PDF
Solving Large Scale Unconstrained Minimization Problems by a New ODE Numerical Integration Method
11
作者 Tianmin Han Xinlong Luo Yuhuan Han 《Applied Mathematics》 2011年第5期527-532,共6页
In reference [1], for large scale nonlinear equations , a new ODE solving method was given. This paper is a continuous work. Here has gradient structure i.e. , is a scalar function. The eigenvalues of the Jacobian of;... In reference [1], for large scale nonlinear equations , a new ODE solving method was given. This paper is a continuous work. Here has gradient structure i.e. , is a scalar function. The eigenvalues of the Jacobian of;or the Hessian of , are all real number. So the new method is very suitable for this structure. For quadratic function the convergence was proved and the spectral radius of iteration matrix was given and compared with traditional method. Examples show for large scale problems (dimension ) the new method is very efficient. 展开更多
关键词 UNCONSTRAINED MINIMIZATION problem Gradient EQUATIONS QUADRATIC Model Spectral RADIUS ODE Numerical integration
下载PDF
FRACTIONAL ORDER BOUNDARY VALUE PROBLEM WITH INTEGRAL BOUNDARY CONDITIONS INVOLVING PETTIS INTEGRAL 被引量:5
12
作者 Hussein A.H. Salem 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期661-672,共12页
In this article, we investigate the existence of Pseudo solutions for some fractional order boundary value problem with integral boundary conditions in the Banach space of continuous function equipped with its weak to... In this article, we investigate the existence of Pseudo solutions for some fractional order boundary value problem with integral boundary conditions in the Banach space of continuous function equipped with its weak topology. The class of such problems constitute a very interesting and important class of problems. They include two, three, multi-point and nonlocal boundary-value problems as special cases. In our investigation, the right hand side of the above problem is assumed to be Pettis integrable function. To encompass the full scope of this article, we give an example illustrating the main result. 展开更多
关键词 Fractional calculus Pseudo solution boundary value problem Pettis integrals
下载PDF
Location and allocation problem for spare parts depots on integrated logistics support 被引量:3
13
作者 WEN Meilin LU Bohan +1 位作者 LI Shuyu KANG Rui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第6期1252-1259,共8页
In equipment integrated logistics support(ILS), the supply capability of spare parts is a significant factor. There are lots of depots in the traditional support system, which makes too many redundant spare parts and ... In equipment integrated logistics support(ILS), the supply capability of spare parts is a significant factor. There are lots of depots in the traditional support system, which makes too many redundant spare parts and causes high cost of support. Meanwhile,the inconsistency among depots makes it difficult to manage spare parts. With the development of information technology and transportation, the supply network has become more efficient. In order to further improve the efficiency of supply-support work and the availability of the equipment system, building a system of one centralized depot with multiple depots becomes an appropriate way.In this case, location selection of the depots including centralized depots and multiple depots becomes a top priority in the support system. This paper will focus on the location selection problem of centralized depots considering ILS factors. Unlike the common location selection problem, depots in ILS require a higher service level. Therefore, it becomes desperately necessary to take the high requirement of the mission into account while determining location of depots. Based on this, we raise an optimal depot location model. First, the expected transportation cost is calculated.Next, factors in ILS such as response time, availability and fill rate are analyzed for evaluating positions of open depots. Then, an optimization model of depot location is developed with the minimum expected cost of transportation as objective and ILS factors as constraints. Finally, a numerical case is studied to prove the validity of the model by using the genetic algorithm. Results show that depot location obtained by this model can guarantee the effectiveness and capability of ILS well. 展开更多
关键词 location problem spare parts depot integrated logis tics support genetic algorithm.
下载PDF
NEW NUMERICAL METHOD FOR VOLTERRA INTEGRAL EQUATION OF THE SECOND KIND IN PIEZOELASTIC DYNAMIC PROBLEMS 被引量:2
14
作者 丁皓江 王惠明 陈伟球 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第1期16-23,共8页
The elastodynamic problems of piezoelectric hollow cylinders and spheres under radial deformation can be transformed into a second kind Volterra integral equation about a function with respect to time, which greatly s... The elastodynamic problems of piezoelectric hollow cylinders and spheres under radial deformation can be transformed into a second kind Volterra integral equation about a function with respect to time, which greatly simplifies the solving procedure for such elastodynamic problems. Meanwhile, it becomes very important to find a way to solve the second kind Volterra integral equation effectively and quickly. By using an interpolation function to approximate the unknown function, two new recursive formulae were derived, based on which numerical solution can be obtained step by step. The present method can provide accurate numerical results efficiently. It is also very stable for long time calculating. 展开更多
关键词 PIEZOELECTRIC elastodynamic problem Volterra integral equation numerical solution recursive formulae
下载PDF
Second Order Periodic Boundary Value Problems Involving the Distributional Henstock-Kurzweil Integral 被引量:3
15
作者 Xueyuan Zhou Guoju Ye 《Advances in Pure Mathematics》 2012年第5期330-336,共7页
We apply the distributional derivative to study the existence of solutions of the second order periodic boundary value problems involving the distributional Henstock-Kurzweil integral. The distributional Henstock-Kurz... We apply the distributional derivative to study the existence of solutions of the second order periodic boundary value problems involving the distributional Henstock-Kurzweil integral. The distributional Henstock-Kurzweil integral is a general intergral, which contains the Lebesgue and Henstock-Kurzweil integrals. And the distributional derivative includes ordinary derivatives and approximate derivatives. By using the method of upper and lower solutions and a fixed point theorem, we achieve some results which are the generalizations of some previous results in the literatures. 展开更多
关键词 Periodic Boundary Value problem Distributional Henstock-Kurzweil integrAL Distributional DERIVATIVE EXISTENCE UPPER and LOWER Solutions Fixed Point
下载PDF
ON THE UNIQUENESS OF BOUNDARY INTEGRAL EQUATION FOR THE EXTERIOR HELMHOLTZ PROBLEM 被引量:1
16
作者 王清 徐博侯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第10期965-971,共7页
From the point of view of energy analysis, the cause that the uniqueness of the boundary integral equation induced from the exterior Helmholtz problem does not hold is investigated in this paper. It is proved that the... From the point of view of energy analysis, the cause that the uniqueness of the boundary integral equation induced from the exterior Helmholtz problem does not hold is investigated in this paper. It is proved that the Sommerfeld's condition at the infinity is changed so that it is suitable not only for the radiative wave but also for the absorptive wave when we use the boundary integral equation to describe the exterior Helmholtz problem. There fore, the total energy of the system is conservative. The mathematical dealings to guarantee the uniqueness are discussed based upon this explanation. 展开更多
关键词 exterior Helmholtz problem boundary integral equation UNIQUENESS
下载PDF
NOVEL REGULARIZED BOUNDARY INTEGRAL EQUATIONS FOR POTENTIAL PLANE PROBLEMS 被引量:1
17
作者 张耀明 吕和祥 王利民 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第9期1165-1170,共6页
The universal practices have been centralizing on the research of regularization to the direct boundary integal equations (DBIEs). The character is elimination of singularities by using the simple solutions. However... The universal practices have been centralizing on the research of regularization to the direct boundary integal equations (DBIEs). The character is elimination of singularities by using the simple solutions. However, up to now the research of regularization to the first kind integral equations for plane potential problems has never been found in previous literatures. The presentation is mainly devoted to the research on the regularization of the singular boundary integral equations with indirect unknowns. A novel view and idea is presented herein, in which the regularized boundary integral equations with indirect unknowns without including the Cauchy principal value (CPV) and Hadamard-finite-part (HFP) integrals are established for the plane potential problems. With some numerical results, it is shown that the better accuracy and higher efficiency, especially on the boundary, can be achieved by the present system. 展开更多
关键词 potential plane problems boundary integral equations (BIEs) indirect BIEs regularization of BIEs
下载PDF
Integral Global Minimization of Constrained Problems with Discontinuous Penalty Functions 被引量:1
18
作者 吴斌 崔洪泉 郑权 《Journal of Shanghai University(English Edition)》 CAS 2005年第5期385-390,共6页
A class of discontinuous penalty functions was proposed to solve constrained minimization problems with the integral approach to global optimization, m-mean value and v-variance optimality conditions of a constrained ... A class of discontinuous penalty functions was proposed to solve constrained minimization problems with the integral approach to global optimization, m-mean value and v-variance optimality conditions of a constrained and penalized minimization problem were investigated. A nonsequential algorithm was proposed. Numerical examples were given to illustrate the effectiveness of the algorithm. 展开更多
关键词 integral global minimization constrained minimization problems discontinuous penalty functions.
下载PDF
Numerical Solution of Mean-Square Approximation Problem of Real Nonnegative Function by the Modulus of Double Fourier Integral 被引量:1
19
作者 Petro Savenko Myroslava Tkach 《Applied Mathematics》 2011年第9期1076-1090,共15页
A nonlinear problem of mean-square approximation of a real nonnegative continuous function with respect to two variables by the modulus of double Fourier integral dependent on two real parameters with use of the smoot... A nonlinear problem of mean-square approximation of a real nonnegative continuous function with respect to two variables by the modulus of double Fourier integral dependent on two real parameters with use of the smoothing functional is studied. Finding the optimal solutions of this problem is reduced to solution of the Hammerstein type two-dimensional nonlinear integral equation. The numerical algorithms to find the branching lines and branching-off solutions of this equation are constructed and justified. Numerical examples are presented. 展开更多
关键词 Mean-Square Approximation Discrete FOURIER Transform TWO-DIMENSIONAL NONLINEAR integral Equation NONUNIQUENESS and Branching of Solutions TWO-DIMENSIONAL NONLINEAR Spectral problem
下载PDF
THE EXACT INTEGRAL EQUATION OF HERTZ’S CONTACT PROBLEM
20
作者 云天铨 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第2期181-185,共5页
This paper presents the exact integral equation of Hertz's contact problem, which is obtained by taking into account the horizontal displacement of points in the contacted surfaces due to pressure.
关键词 ELASTICITY contact problem integral equations
下载PDF
上一页 1 2 121 下一页 到第
使用帮助 返回顶部