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    题名 作者 年代 出处 被引量
1A Parallel Algorithm for Adaptive Local Refinement of Tetrahedral Meshes Using Bisection显示文摘Local mesh refinement is one of the key steps in the implementations of adaptive finite element methods.This paper presents a parallel algorithm for distributed memory parallel computers for adaptive local refinement of tetrahedral meshes using bisection.This algorithm is used in PHG,Parallel Hierarchical Grid (http://lsec.cc.ac.cn/phg/),a toolbox under active development for parallel adaptive finite element solutions of partial differential equations.The algorithm proposed is characterized by allowing simultaneous refinement of submeshes to arbitrary levels before synchronization between submeshes and without the need of a central coordinator process for managing new vertices.Using the concept of canonical refinement, a simple proof of the independence of the resulting mesh on the mesh partitioning is given,which is useful in better understanding the behaviour of the bisectioning refinement procedure.Lin-Bo Zhang 2009Numerical Mathematics(Theory,Methods and Applications)2009,2,1:27
2Superconvergence of a Nonconforming Finite Element Approximation to Viscoelasticity Type Equations on Anisotropic Meshes显示文摘The main aim of this paper is to study the approximation to viscoelasticity type equations with a Crouzeix-Raviart type nonconforming finite element on the anisotropic meshes. The superclose property of the exact solution and the optimal error estimate of its derivative with respect to time are derived by using some novel techniques. Moreover, employing a postprocessing technique, the global superconvergence property for the discretization error of the postprocessed discrete solution to the solution itself is studied.Dongyang Shi Yucheng Peng Shaochun Chen 2006Numerical Mathematics A Journal of Chinese Universities(English Series)2006,15,4:21
3A New Approach to Nonlinear Partial Differential Equations显示文摘In this paper,a novel method called variational iteration method is proposed to solve nonlinear partial differential equations without linearization or small perturbations.In this method,a correction functional is constructed by a general Lagrange multiplier,which can be identified via variational theory.An analytical solution can be obtained from its trial- function with possible unknown constants,which can be identified by imposing the boundary conditions,by successively iteration.Jihuan HE (Shanghai University,Shanghai Institute of Applied Mathematics and Mechanics,Shanghai 2 0 0 0 72 ,China) 1997Communications in Nonlinear Science and Numerical Simulation1997,2,4:16
4Global asymptotic stability of a two species competitive system with stage structure and harvesting显示文摘The dynamics of a two species competitive system, where the species one has two stages, a immature stage and a mature stage with harvesting, and the growth of the species two is of Lotka-Volterra nature, is modelled by a system of retarded functional differential equations. We obtain the conditions for global asymptotic stability of three nonnegative equilibria and the threshold of harvesting mature population. The effect of the delay on the population at equilibrium and the optimal harvesting of mature population are also considered.XinyuSONG LansunCHEN2001Communications in Nonlinear Science and Numerical Simulation2001,6,2:11
5A Globally Convergent Polak-Ribiere-Polyak Conjugate Gradient Method with Armijo-Type Line Search显示文摘In this paper, we propose a globally convergent Polak-Ribiere-Polyak (PRP) conjugate gradient method for nonconvex minimization of differentiable functions by employing an Armijo-type line search which is simpler and less demanding than those defined in [4,10]. A favorite property of this method is that we can choose the initial stepsize as the one-dimensional minimizer of a quadratic modelΦ(t):= f(xk)+tgkTdk+(1/2) t2dkTQkdk, where Qk is a positive definite matrix that carries some second order information of the objective function f. So, this line search may make the stepsize tk more easily accepted. Preliminary numerical results show that this method is efficient.Gaohang Yu Lutai Guan Zengxin Wei 2006Numerical Mathematics A Journal of Chinese Universities(English Series)2006,15,4:11
6Convergence Analysis of a Block-by-Block Method for Fractional Differential Equations显示文摘The block-by-block method,proposed by Linz for a kind of Volterra integral equations with nonsingular kernels,and extended by Kumar and Agrawal to a class of initial value problems of fractional differential equations(FDEs)with Caputo derivatives,is an efficient and stable scheme.We analytically prove and numerically verify that this method is convergent with order at least 3 for any fractional order indexα>0.Jianfei Huang Yifa Tang Luis Vázquez 2012Numerical Mathematics(Theory,Methods and Applications)2012,5,2:11
7Fast Texture Segmentation Based on Semi-Local Region Descriptor and Active Contour显示文摘In this paper,we present an efficient approach for unsupervised segmentation of natural and textural images based on the extraction of image features and a fast active contour segmentation model.We address the problem of textures where neither the gray-level information nor the boundary information is adequate for object extraction.This is often the case of natural images composed of both homogeneous and textured regions.Because these images cannot be in general directly processed by the gray-level information,we propose a new texture descriptor which intrinsically defines the geometry of textures using semi-local image information and tools from differential geometry.Then,we use the popular Kullback-Leibler distance to design an active contour model which distinguishes the background and textures of interest.The existence of a minimizing solution to the proposed segmentation model is proven.Finally, a texture segmentation algorithm based on the Split-Bregman method is introduced to extract meaningful objects in a fast way.Promising synthetic and real-world results for gray-scale and color images are presented.Nawal Houhou Jean-Philippe Thiran Xavier Bresson 2009Numerical Mathematics(Theory,Methods and Applications)2009,2,4:10
8A Nonconforming Arbitrary Quadrilateral Finite Element Method for Approximating Maxwell's Equations显示文摘The main aim of this paper is to provide convergence analysis of Quasi-Wilson nonconforming finite element to Maxwell's equations under arbitrary quadrilateral meshes.The error estimates are derived,which are the same as those for conforming elements under conventional regular meshes.Dongyang Shi Lifang Pei Shaochun Chen 2007Numerical Mathematics A Journal of Chinese Universities(English Series)2007,16,4:9
9The Superconvergence of Mixed FiniteElement Methods for Nonlinear HyperbolicEquations显示文摘Improved L2-error estimates are computed for mixed finite element methods for second order nonlinear hyperbolic equations. Superconvergence results, L∞intime and discrete L2 in space, are derived for both the solution and gradients on therectangular domain. Results are given for the continuous-time case.YanpingCHEN YunqingHUANG 1998Communications in Nonlinear Science and Numerical Simulation1998,3,3:8
10GENERALIZED MATRIX MULTISPLITTING RELAXATION METHODS AND THEIR CONVERGENCE显示文摘In this paper, we set up a general framework of parallel matrix mullisplitting relaxation methods for solving large scale system of linear equations. We investigate the convergence properties of this framework and give several sufficient conditions ensuring it to converge as well as diverge. At last, we conclude a necessary and sufficient condition for the convergence of this framework when the coefficient matrix is an L-matrix.白中治 王德人 1993Numerical Mathematics A Journal of Chinese Universities(English Series)1993,2,1:8
11COMPUTATION OF VECTOR VALUED BLENDING RATIONAL INTERPOLANTS显示文摘As we know, Newton's interpolation polynomial is based on divided differ-ences which can be calculated recursively by the divided-difference scheme while Thiele'sinterpolating continued fractions are geared towards determining a rational functionwhich can also be calculated recursively by so-called inverse differences. In this paper,both Newton's interpolation polynomial and Thiele's interpolating continued fractionsare incorporated to yield a kind of bivariate vector valued blending rational interpolantsby means of the Samelson inverse. Blending differences are introduced to calculate theblending rational interpolants recursively, algorithm and matrix-valued case are dis-cussed and a numerical example is given to illustrate the efficiency of the algorithm.檀结庆 2003Numerical Mathematics A Journal of Chinese Universities(English Series)2003,12,1:8
12The Effects of Limiters on High Resolution Computations of Hypersonic Flows over Bodies with Complex Shapes显示文摘IntroductionSincetheideaofTVDwasproposedbyHarten[1]sometwodecadesago,varioustypesofhighresolutionschemesforsimulatingthecompr...BoZHENG Chun-HianLEE 1998Communications in Nonlinear Science and Numerical Simulation1998,3,2:8
13A CONDITIONAL STABILITY FOR AN INVERSE PROBLEM ARISING IN GROUNDWATER POLLUTION显示文摘An inverse problem of determining magnitude of groundwater pollution in a hydrologic region is investigated. By applying integral identity methods, a conditional stability for the inverse problem here is constructed with aids of an optimal adjoint problem and a suitable topology.李功胜 谭永基 2005Numerical Mathematics A Journal of Chinese Universities(English Series)2005,14,3:7
14A New Homotopy Method for Nonlinear Complementarity Problems显示文摘In this paper, we present a new homotopy method for the nonlinear complementarity problems. Without the regularity or non-singulary assumptions for▽F(x), we prove that our homotopy equations have a bounded solution curve. The numerical tests confirm the efficiency of our proposed method.Jundi Ding Hongyou Yin 2007Numerical Mathematics A Journal of Chinese Universities(English Series)2007,16,2:6
15Variational Iteration Method for Delay Differential Equations显示文摘The variational iteration method is shown to be applicable to delay differential equations for analytical approximateJihuan HE (Shanghai University,Shanghai Institute of Applied Mathematics and Mechanics,Shanghai 2 0 0 0 72 ,China) 1997Communications in Nonlinear Science and Numerical Simulation1997,2,4:6
16Advances in Studies and Applications of Centroidal Voronoi Tessellations显示文摘Centroidal Voronoi tessellations(CVTs) have become a useful tool in many applications ranging from geometric modeling,image and data analysis,and numerical partial differential equations,to problems in physics,astrophysics,chemistry,and biology. In this paper,we briefly review the CVT concept and a few of its generalizations and well-known properties.We then present an overview of recent advances in both mathematical and computational studies and in practical applications of CVTs.Whenever possible,we point out some outstanding issues that still need investigating.Qiang Du Max Gunzburger Lili Ju 2010Numerical Mathematics(Theory,Methods and Applications)2010,3,2:6
17THE FINITE DIFFERENCE STREAMLINE DIFFUSION METHODS FOR TIME-DEPENDENT CONVECTION-DIFFUSION EQUATIONS显示文摘In this paper, two finite difference streamline diffusion (FDSD) schemes for solving two-dimensional time-dependent convection-diffusion equations are constructed. Stability and optimal order error estimati-ions for considered schemes are derived in the norm stronger than L^2-norm.孙澈 沈慧 1998Numerical Mathematics A Journal of Chinese Universities(English Series)1998,7,1:6
18On the Approximation of the Derivatives of Spline Quasi-Interpolation in Cubic Spline Space S_(3)^(1,2)(∆_(mn)^((2)))显示文摘In this paper,based on the basis composed of two sets of splines with distinct local supports,cubic spline quasi-interpolating operators are reviewed on nonuniform type-2 triangulation.The variation diminishing operator is defined by discrete linear functionals based on a fixed number of triangular mesh-points,which can reproduce any polynomial of nearly best degrees.And by means of the modulus of continuity,the estimation of the operator approximating a real sufficiently smooth function is reviewed as well.Moreover,the derivatives of the nearly optimal variation diminishing operator can approximate that of the real sufficiently smooth function uniformly over quasi-uniform type-2 triangulation.And then the convergence results are worked out.Jiang Qian Fan Wang 2014Numerical Mathematics(Theory,Methods and Applications)2014,7,1:6
19A Coordinate Gradient Descent Method for Nonsmooth Nonseparable Minimization显示文摘This paper presents a coordinate gradient descent approach for minimizing the sum of a smooth function and a nonseparable convex function.We find a search direction by solving a subproblem obtained by a second-order approximation of the smooth function and adding a separable convex function.Under a local Lipschitzian error bound assumption,we show that the algorithm possesses global and local linear convergence properties.We also give some numerical tests(including image recovery examples) to illustrate the efficiency of the proposed method.Zheng-Jian Bai Michael K. Ng Liqun Qi 2009Numerical Mathematics(Theory,Methods and Applications)2009,2,4:6
20An Approximate Solution Technique Depending on an Artificial Parameter: A Special Example显示文摘IntroductionInthelasttwodecadeswiththerapiddevelopmentofnonlinearscience,therehasappearedeverincreasinginterestofscientists...Jihuan HE (Shanghai University, Shanghai Institute of Applied Mathematics and Mechanics, Shanghai 200072, China) 1998Communications in Nonlinear Science and Numerical Simulation1998,3,2:5
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