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Using reproducing kernel for solving a class of partial differential equation with variable-coefficients
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作者 王玉兰 朝鲁 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第1期129-137,共9页
How to solve the partial differential equation has been attached importance to by all kinds of fields. The exact solution to a class of partial differential equation with variable-coefficient is obtained in reproducin... How to solve the partial differential equation has been attached importance to by all kinds of fields. The exact solution to a class of partial differential equation with variable-coefficient is obtained in reproducing kernel space. For getting the approximate solution, give an iterative method, convergence of the iterative method is proved. The numerical example shows that our method is effective and good practicability. 展开更多
关键词 iterative method exact solution approximate solution variable-coefficient partial differential equation reproducing kernel
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A SEMI-ANALYSIS METHOD OF DIFFERENTIAL EQUATIONS WITH VARIABLE COEFFICIENTS UNDER COMPLICATED BOUNDARY CONDITIONS
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作者 黎明安 王忠民 郭志勇 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第2期241-246,共6页
Based on a method of finite element model and combined with matrix theory, a method for solving differential equation with variable coefficients is proposed. With the method, it is easy to deal with the differential e... Based on a method of finite element model and combined with matrix theory, a method for solving differential equation with variable coefficients is proposed. With the method, it is easy to deal with the differential equations with variable coefficients. On most occasions and due to the nonuniformity nature, nonlinearity property can cause the equations of the kinds. Using the model, the satisfactory valuable results with only a few units can be obtained. 展开更多
关键词 differential equation with variable coefficients equivalent parameter solution in the domain solution of semi_analysis
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Numerical Methods for Boundary Value Problems in Variable Coefficient Ordinary Differential Equations 被引量:1
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作者 ZHAO Ting-ting CAI Wei-yun 《Chinese Quarterly Journal of Mathematics》 2025年第3期295-303,共9页
In order to solve the problem of the variable coefficient ordinary differen-tial equation on the bounded domain,the Lagrange interpolation method is used to approximate the exact solution of the equation,and the error... In order to solve the problem of the variable coefficient ordinary differen-tial equation on the bounded domain,the Lagrange interpolation method is used to approximate the exact solution of the equation,and the error between the numerical solution and the exact solution is obtained,and then compared with the error formed by the difference method,it is concluded that the Lagrange interpolation method is more effective in solving the variable coefficient ordinary differential equation. 展开更多
关键词 variable coefficient ordinary differential equations Lagrange interpolation Difference methods
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A numerical method based on boundary integral equations and radial basis functions for plane anisotropic thermoelastostatic equations with general variable coefficients 被引量:2
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作者 W.T.ANG X.WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第4期551-566,共16页
A boundary integral method with radial basis function approximation is proposed for numerically solving an important class of boundary value problems governed by a system of thermoelastostatic equations with variable ... A boundary integral method with radial basis function approximation is proposed for numerically solving an important class of boundary value problems governed by a system of thermoelastostatic equations with variable coe?cients. The equations describe the thermoelastic behaviors of nonhomogeneous anisotropic materials with properties that vary smoothly from point to point in space. No restriction is imposed on the spatial variations of the thermoelastic coe?cients as long as all the requirements of the laws of physics are satis?ed. To check the validity and accuracy of the proposed numerical method, some speci?c test problems with known solutions are solved. 展开更多
关键词 elliptic partial differential equation variable coefficient boundary element method radial basis function anisotropic thermoelastostatics
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Domain-based noise removal method using fourth-order partial differential equation
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作者 曾维理 谭湘花 路小波 《Journal of Southeast University(English Edition)》 EI CAS 2011年第2期154-158,共5页
Due to the fact that the fourth-order partial differential equation (PDE) for noise removal can provide a good trade-off between noise removal and edge preservation and avoid blocky effects often caused by the secon... Due to the fact that the fourth-order partial differential equation (PDE) for noise removal can provide a good trade-off between noise removal and edge preservation and avoid blocky effects often caused by the second-order PDE, a domain-based fourth-order PDE method for noise removal is proposed. First, the proposed method segments the image domain into two domains, a speckle domain and a non-speckle domain, based on the statistical properties of isolated speckles in the Laplacian domain. Then, depending on the domain type, different conductance coefficients in the proposed fourth-order PDE are adopted. Moreover, the frequency approach is used to determine the optimum iteration stopping time. Compared with the existing fourth-order PDEs, the proposed fourth-order PDE can remove isolated speckles and keeps the edges from being blurred. Experimental results show the effectiveness of the proposed method. 展开更多
关键词 fourth-order partial differential equation conductance coefficient speckle domain image denoising
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A Study of Some Nonlinear Partial Differential Equations by Using Adomian Decomposition Method and Variational Iteration Method 被引量:1
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作者 Maha S. M. Shehata 《American Journal of Computational Mathematics》 2015年第2期195-203,共9页
In this paper, a numerical solution of nonlinear partial differential equation, Benjamin-Bona-Mahony (BBM) and Cahn-Hilliard equation is presented by using Adomain Decomposition Method (ADM) and Variational Iteration ... In this paper, a numerical solution of nonlinear partial differential equation, Benjamin-Bona-Mahony (BBM) and Cahn-Hilliard equation is presented by using Adomain Decomposition Method (ADM) and Variational Iteration Method (VIM). The results reveal that the two methods are very effective, simple and very close to the exact solution. 展开更多
关键词 Wave variables Adomian Decomposition METHOD (ADM) Variational ITERATION METHOD (VIM) Nonlinear partial differential equation PDES BBM and CAHN-HILLIARD equations
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Comparative Study of Radial Basis Functions for PDEs with Variable Coefficients
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作者 Fuzhang Wang Congcong Li Kehong Zheng 《Journal of Harbin Institute of Technology(New Series)》 CAS 2021年第6期91-96,共6页
The radial basis functions(RBFs)play an important role in the numerical simulation processes of partial differential equations.Since the radial basis functions are meshless algorithms,its approximation is easy to impl... The radial basis functions(RBFs)play an important role in the numerical simulation processes of partial differential equations.Since the radial basis functions are meshless algorithms,its approximation is easy to implement and mathematically simple.In this paper,the commonly⁃used multiquadric RBF,conical RBF,and Gaussian RBF were applied to solve boundary value problems which are governed by partial differential equations with variable coefficients.Numerical results were provided to show the good performance of the three RBFs as numerical tools for a wide range of problems.It is shown that the conical RBF numerical results were more stable than the other two radial basis functions.From the comparison of three commonly⁃used RBFs,one may obtain the best numerical solutions for boundary value problems. 展开更多
关键词 radial basis functions partial differential equations variable coefficient
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EXACT ANALYTIC METHOD FG(?) SOLVING VARIABLE COEFFICIENT DIFFERENTIAL EQUATION
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作者 纪振义 叶开源 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第10期885-896,共12页
Many engineering problems can be reduced to the solution of a variable coefficient differential equation. In this paper, the exact analytic method is suggested to solve variable coefficient differential equations unde... Many engineering problems can be reduced to the solution of a variable coefficient differential equation. In this paper, the exact analytic method is suggested to solve variable coefficient differential equations under arbitrary boundary condition. By this method, the general computation formal is obtained. Its convergence in proved. We can get analytic expressions which converge to exact solution and its higher order derivatives uniformy Four numerical examples are given, which indicate that satisfactory results can he obtanedby this method. 展开更多
关键词 SOLVING variable COEFFICIENT differential equation EXACT ANALYTIC METHOD FG
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A Conceptual Numerical Model of the Wave Equation Using the Complex Variable Boundary Element Method
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作者 Bryce D. Wilkins Theodore V. Hromadka Randy Boucher 《Applied Mathematics》 2017年第5期724-735,共12页
In this work, a conceptual numerical solution of the two-dimensional wave partial differential equation (PDE) is developed by coupling the Complex Variable Boundary Element Method (CVBEM) and a generalized Fourier ser... In this work, a conceptual numerical solution of the two-dimensional wave partial differential equation (PDE) is developed by coupling the Complex Variable Boundary Element Method (CVBEM) and a generalized Fourier series. The technique described in this work is suitable for modeling initial-boundary value problems governed by the wave equation on a rectangular domain with Dirichlet boundary conditions and an initial condition that is equal on the boundary to the boundary conditions. The new numerical scheme is based on the standard approach of decomposing the global initial-boundary value problem into a steady-state component and a time-dependent component. The steady-state component is governed by the Laplace PDE and is modeled with the CVBEM. The time-dependent component is governed by the wave PDE and is modeled using a generalized Fourier series. The approximate global solution is the sum of the CVBEM and generalized Fourier series approximations. The boundary conditions of the steady-state component are specified as the boundary conditions from the global BVP. The boundary conditions of the time-dependent component are specified to be identically zero. The initial condition of the time-dependent component is calculated as the difference between the global initial condition and the CVBEM approximation of the steady-state solution. Additionally, the generalized Fourier series approximation of the time-dependent component is fitted so as to approximately satisfy the derivative of the initial condition. It is shown that the strong formulation of the wave PDE is satisfied by the superposed approximate solutions of the time-dependent and steady-state components. 展开更多
关键词 Complex variable Boundary Element Method (CVBEM) partial differential equations (PDEs) NUMERICAL Solution Techniques LAPLACE equation Wave equation
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Validation of general linear modeling for identifying factors associated with Quality of Life: A comparison with structural equation modeling
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作者 Naoko Kumagai Motonori Hatta +1 位作者 Yashiyasu Okuhara Hideki Origasa 《Health》 2013年第11期1884-1888,共5页
Purpose: General linear modeling (GLM) is usually applied to investigate factors associated with the domains of Quality of Life (QOL). A summation score in a specific sub-domain is regressed by a statistical model inc... Purpose: General linear modeling (GLM) is usually applied to investigate factors associated with the domains of Quality of Life (QOL). A summation score in a specific sub-domain is regressed by a statistical model including factors that are associated with the sub-domain. However, using the summation score ignores the influence of individual questions. Structural equation modeling (SEM) can account for the influence of each question’s score by compositing a latent variable from each question of a sub-domain. The objective of this study is to determine whether a conventional approach such as GLM, with its use of the summation score, is valid from the standpoint of the SEM approach. Method: We used the Japanese version of the Maugeri Foundation Respiratory Failure Questionnaire, a QOL measure, on 94 patients with heart failure. The daily activity sub-domain of the questionnaire was selected together with its four accompanying factors, namely, living together, occupation, gender, and the New York Heart Association’s cardiac function scale (NYHA). The association level between individual factors and the daily activity sub-domain was estimated using SEM?and GLM, respectively. The standard partial regression coefficients of GLM and standardized path coefficients of SEM were compared. If?these coefficients were similar (absolute value of the difference -0.06 and -0.07 for the GLM and SEM. Likewise, the estimates of occupation, gender, and NYHA were -0.18 and -0.20, -0.08 and -0.08, 0.51 and 0.54, respectively. The absolute values of the difference for each factor were 0.01, 0.02, 0.00, and 0.03, respectively. All differences were less than 0.05. This means that these two approaches lead to similar conclusions. Conclusion: GLM is a valid method for exploring association factors with a domain in QOL. 展开更多
关键词 General LINER MODELING LATENT variable Standardized Path COEFFICIENT Standard partial Regression COEFFICIENT Structural equation MODELING
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Dirichlet boundary value problem with variable growth
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作者 董增福 付永强 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第3期262-266,共5页
In this paper, we study higher order elliptic partial differential equations with variable growth, and obtain the existence of solutions in the setting of Wm,p(x) spaces by means of an abstract result for variationa... In this paper, we study higher order elliptic partial differential equations with variable growth, and obtain the existence of solutions in the setting of Wm,p(x) spaces by means of an abstract result for variational inequalities obtained by Gossez and Mustonen. Our result generalizes the corresponding one of Kováik and Rákosník. 展开更多
关键词 boundary value problem elliptic partial differential equation variable growth
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On a Linear Partial Differential Equation of the Higher Order in Two Variables with Initial Condition Whose Coefficients are Real-valued Simple Step Functions
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作者 PANTSULAIA Gogi GIORGADZE Givi 《Journal of Partial Differential Equations》 CSCD 2016年第1期1-13,共13页
By using the method developed in the paper [Georg. Inter. J. Sci. Tech., Volume 3, Issue 1 (2011), 107-129], it is obtained a representation in an explicit form of the weak solution of a linear partial differential... By using the method developed in the paper [Georg. Inter. J. Sci. Tech., Volume 3, Issue 1 (2011), 107-129], it is obtained a representation in an explicit form of the weak solution of a linear partial differential equation of the higher order in two variables with initial condition whose coefficients are real-valued simple step functions. 展开更多
关键词 Linear partial differential equation of the higher order in two variables Fourier differential operator.
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A Partial Differential ANRDPM Image Denoising Model Based on A New Anti-Noise Coefficient and Reverse Diffusion Idea
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作者 Yuze Chen Xianchun Zhou +3 位作者 Siqi Lu Binxin Tang Mengnan Lv Zhiting Du 《Instrumentation》 2024年第4期21-34,共14页
To overcome the problem of insufficient expression of fine texture when gradient mode is used as an image feature extraction operator in traditional PM model,which leads to excessive diffusion in these fine texture re... To overcome the problem of insufficient expression of fine texture when gradient mode is used as an image feature extraction operator in traditional PM model,which leads to excessive diffusion in these fine texture regions and texture ambiguity,this paper proposes ANRDPM(Anti-noise and Reverse Diffusion PM model)noise reduction model based on the new anti-noise coefficient and reverse diffusion concept.In this model,the meter gradient operator is used as the image feature extractor to solve the shortage of the traditional gradient operator in the ability to express details.Secondly,a new anti-noise coefficient based on Gaussian curvature and noise intensity is proposed to solve the problem that the meter gradient operator is allergic to large noise points.In addition,a reverse diffusion filter based on a local variance of residuals is introduced to enhance the smoothed texture information in the image.Finally,the new model is discretized by a finite difference algorithm,and simulation results show that the proposed ANRDPM model not only performs well in smoothing image noise,but also effectively protects image texture information and structural integrity. 展开更多
关键词 image noise reduction partial differential equation new anti-noise coefficient anisotropy total variation
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The Link between Stochastic Differential Equations with Non-Markovian Coefficients and Backward Stochastic Partial Differential Equations 被引量:1
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作者 Lin LIN Fang XU Qi ZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2021年第3期447-457,共11页
In this paper, we conjecture and prove the link between stochastic differential equations with non-Markovian coefficients and nonlinear parabolic backward stochastic partial differential equations, which is an extensi... In this paper, we conjecture and prove the link between stochastic differential equations with non-Markovian coefficients and nonlinear parabolic backward stochastic partial differential equations, which is an extension of such kind of link in Markovian framework to non-Markovian framework.Different from Markovian framework, where the corresponding partial differential equation is deterministic, the backward stochastic partial differential equation here has a pair of adapted solutions, and thus the link has a much different form. Moreover, two examples are given to demonstrate the applications of the derived link. 展开更多
关键词 Backward stochastic partial differential equations stochastic differential equations nonMarkovian coefficients Girsanov transformation Feynman–Kac formula
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OSCILLATIONS OF SOLUTIONS OF NEUTRAL DIFFERENTIAL EQUATIONS WITH VARIABLE COEFFICIENTS AND DELAYS
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作者 Guan Xinping &.Yang Jun (Northeast Heavy Machinery Institute, ) 《Annals of Differential Equations》 1995年第4期397-403,共7页
Consider the neutral differential equations with variable coefficients and delays [x(t)-p(t)x(t-r(t))]'+ Qj(t)x(t-σj(t))=0. (1)We establish sufficient conditions for the oscillation of equation (1). Our condition... Consider the neutral differential equations with variable coefficients and delays [x(t)-p(t)x(t-r(t))]'+ Qj(t)x(t-σj(t))=0. (1)We establish sufficient conditions for the oscillation of equation (1). Our condition is 'sharp' in the sense that when all the coefficients and delays of the equation are constants.Our conclusions improve and generalize some known results. 展开更多
关键词 Neutral differential equations Oscillation variable coefficients and delays.
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Initial-value Problems for Extended KdV-Burgers Equations via Generalized Conditional Symmetries 被引量:4
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作者 张顺利 李吉娜 《Chinese Physics Letters》 SCIE CAS CSCD 2007年第6期1433-1436,共4页
We classify initial-value problems for extended KdV-Burgers equations via generalized conditional symmetries. These equations can be reduced to Cauchy problems for some systems of first-order ordinary differential equ... We classify initial-value problems for extended KdV-Burgers equations via generalized conditional symmetries. These equations can be reduced to Cauchy problems for some systems of first-order ordinary differential equations. The obtained reductions cannot be derived within the framework of the standard Lie approach. 展开更多
关键词 partial-differential-equationS NONLINEAR DIFFUSION-equationS EVOLUTION-equationS BOUSSINESQ equation variable SEPARATION REDUCTION CLASSIFICATION
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Approximate Generalized Conditional Symmetries for the Perturbed Nonlinear Diffusion-Convection Equations 被引量:4
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作者 张顺利 屈长征 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第3期527-530,共4页
The concept of approximate generalized conditional symmetry (A GCS) as a generalization to both approximate Lie point symmetry and generalized conditional symmetry is introduced, and it is applied to study the pertu... The concept of approximate generalized conditional symmetry (A GCS) as a generalization to both approximate Lie point symmetry and generalized conditional symmetry is introduced, and it is applied to study the perturbed nonlinear diffusion-convection equations. Complete classification of those perturbed equations which admit cerrain types of AGCSs is derived. Some approximate solutions to the resulting equations can be obtained via the AGCS and the corresponding unperturbed equations. 展开更多
关键词 partial-differential-equationS FUNCTIONAL variable SEPARATION INITIAL-VALUE PROBLEMS POTENTIAL SYMMETRIES WAVE-equation REDUCTION CLASSIFICATION
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Mean Square Heun’s Method Convergent for Solving Random Differential Initial Value Problems of First Order 被引量:2
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作者 M. A. Sohaly 《American Journal of Computational Mathematics》 2014年第5期474-481,共8页
This paper deals with the construction of Heun’s method of random initial value problems. Sufficient conditions for their mean square convergence are established. Main statistical properties of the approximations pro... This paper deals with the construction of Heun’s method of random initial value problems. Sufficient conditions for their mean square convergence are established. Main statistical properties of the approximations processes are computed in several illustrative examples. 展开更多
关键词 Stochastic partial differential equations Mean SQUARE SENSE Second Order RANDOM variable
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The theoretical analysis of dynamic response on cantilever beam of variable stiffness 被引量:1
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作者 Huo Bingyong Yi Weijian 《Engineering Sciences》 EI 2014年第2期93-96,共4页
The paper presents the theoretical analysis of a variable stiffness beam. The bending stiffness EI varies continuously along the length of the beam. Dynamic equation yields differential equation with variable co- effi... The paper presents the theoretical analysis of a variable stiffness beam. The bending stiffness EI varies continuously along the length of the beam. Dynamic equation yields differential equation with variable co- efficients based on the model of the Euler-Bernoulli beam. Then differential equation with variable coefficients becomes that with constant coefficients by variable substitution. At last, the study obtains the solution of dy- namic equation. The cantilever beam is an object for analysis. When the flexural rigidity at free end is a constant and that at clamped end is varied, the dynamic characteristics are analyzed under several cases. The results dem- onstrate that the natural angular frequency reduces as the fiexural rigidity reduces. When the rigidity of clamped end is higher than that of free end, low-level mode contributes the larger displacement response to the total re- sponse. On the contrary, the contribution of low-level mode is lesser than that of hi^h-level mode. 展开更多
关键词 stiffness function differential equation with variable coefficients cantilever beam
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Random Crank-Nicolson Scheme for Random Heat Equation in Mean Square Sense 被引量:1
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作者 M. T. Yassen M. A. Sohaly Islam Elbaz 《American Journal of Computational Mathematics》 2016年第2期66-73,共8页
The goal of computational science is to develop models that predict phenomena observed in nature. However, these models are often based on parameters that are uncertain. In recent decades, main numerical methods for s... The goal of computational science is to develop models that predict phenomena observed in nature. However, these models are often based on parameters that are uncertain. In recent decades, main numerical methods for solving SPDEs have been used such as, finite difference and finite element schemes [1]-[5]. Also, some practical techniques like the method of lines for boundary value problems have been applied to the linear stochastic partial differential equations, and the outcomes of these approaches have been experimented numerically [7]. In [8]-[10], the author discussed mean square convergent finite difference method for solving some random partial differential equations. Random numerical techniques for both ordinary and partial random differential equations are treated in [4] [10]. As regards applications using explicit analytic solutions or numerical methods, a few results may be found in [5] [6] [11]. This article focuses on solving random heat equation by using Crank-Nicol- son technique under mean square sense and it is organized as follows. In Section 2, the mean square calculus preliminaries that will be required throughout the paper are presented. In Section 3, the Crank-Nicolson scheme for solving the random heat equation is presented. In Section 4, some case studies are showed. Short conclusions are cleared in the end section. 展开更多
关键词 Random partial differential equations (RPDEs) Mean Square Sense (m.s) Second Order Random variable (2r.v.'s) Random Crank-Nicolson Scheme CONVERGENCE CONSISTENCY Stability
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