检索结果-内蒙古大学图书馆

Analytic approximations of Von Krmn plate under arbitrary uniform pressure—equations in integral form

Science China(Physics,Mechanics & Astronomy) 2018年第1期61卷 57-67页

作者： XiaoXu Zhong ShiJun Liao School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Collaborative Innovative Center for Advanced Ship and Deep-Sea Exploration State Key Laboratory of Ocean Engineering Ministry-of-Education Key Laboratory of Scientific and Engineering Computing

Analytic approximations of the Von Karman＇s plate equations in integral form for a circular plate under external uniform pressure to arbitrary magnitude are successfully obtained by means of the homotopy analysis method （HAM）, an analytic approximation technique for highly nonlinear problems. Two HAM-based approaches are proposed for either a given external uniform pressure Q or a given central deflection, respectively. Both of them are valid for uniform pressure to arbitrary magnitude by choosing proper values of the so-called convergence-control parameters c1 and c2 in the frame of the HAM. Besides, it is found that the HAM- based iteration approaches generally converge much faster than the interpolation iterative method. Furthermore, we prove that the interpolation iterative method is a special case of the first-order HAM iteration approach for a given external uniform pressure Q when c1= -0 and c2 = -1, where 0 denotes the interpolation iterative parameter. Therefore, according to the convergence theorem of Zheng and Zhou about the interpolation iterative method, the HAM-based approaches are valid for uniform pressure to arbitrary magnitude at least in the special case c1 = -0 and c2= -1. In addition, we prove that the HAM approach for the Von karman＇s plate equations in differential form is just a special case of the HAM for the Von karman＇s plate equations in integral form mentioned in this paper. All of these illustrate the validity and great potential of the HAM for highly nonlinear problems, and its superiority over perturbation techniques.

关键词： circular plate high nonlinearity homotopy analysis method

来源：评论

学校读者我要写书评

暂无评论

Lie Point Symmetries of Differential-Difference Equations

引用

Communications in Theoretical Physics 2004年第5期41卷 645-648页

作者： DING Wei~1 TANG Xiao-Yan~(2,3) 1 Department of Applied Mathematics,Shanghai Jiao Tong University,Shanghai 200030,China2 Department of Physics,Shanghai Jiao Tong University,Shanghai 200030,China3 State key laboratory of scientific and engineering computing,Institute of Computational Mathematics and scientific engineering computing,Academy of Mathematics and System Sciences,the Chinese Academy of Sciences,P.O.Box 2719,Beijing 100080,China State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics and Scientific Engineering Computing Academy of Mathematics and System Sciences the Chinese Academy of Sciences P.O. Box 2719 Beijing 100080 China

In this paper,the classical Lie group approach is extended to find some Lie point symmetries of differential-difference *** reveals that the obtained Lie point symmetries can constitute a Kac-Moody-Virasoro algebra.

关键词： Lie point symmetry differential-difference equation Kac Moody-Virasoro algebra

来源：评论

学校读者我要写书评

暂无评论

On the regularity of trust region-cg algorithm: With application to deconvolution problem

引用

Science China Mathematics 2003年第3期46卷 312-325页

作者：王彦飞 Laboratory of Remote Sensing Information Sciences Institute of Remote Sensing ApplicationsChinese Academy of Sciences State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematicsand Scientific/Engineering ComputingAcademy of Mathematics and System SciencesChinese Academy of SciencesBeijing 100080China

Deconvolution problem is a main topic in signal processing. Many practical applications are re-quired to solve deconvolution problems. An important example is image reconstruction. Usually, researcherslike to use regularization method to deal with this problem. But the cost of computation is high due to thefact that direct methods are used. This paper develops a trust region-cg method, a kind of iterative methodsto solve this kind of problem. The regularity of the method is proved. Based on the special structure of thediscrete matrix, FFT can be used for calculation. Hence combining trust region-cg method with FFT is suitablefor solving large scale problems in signal processing.

关键词： ill-posed problems, efficient implementation, trust region-cg method, regularity.

来源：评论

学校读者我要写书评

暂无评论

Parallel hybrid iteration methods for block bordered linear systems

引用

APPLIED MATHEMATICS AND COMPUTATION 1997年第1期86卷 37-60页

作者： Bai, ZZ State Key Laboratory of Scientific/Engineering Computing Institute of Computational Mathematics and Scientific/Engineering Computing Chinese Academy of Sciences P.O. Box 2719 Beijing 100080 People's Republic of China

A class of parallel hybrid iteration method and its accelerated overrelaxation variant are established for solving the large sparse block bordered system of linear equations, and their convergence are proved when the coefficient matrix of the linear system is an M-matrix, an II-matrix, and a symmetric positive definite matrix, respectively. (C) Elsevier Science Inc., 1997.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Hierarchical-control-based output synchronization of coexisting attractor networks

引用

Chinese Physics B 2010年第2期19卷 127-134页

作者：宋运忠唐贻发 Complex Networks Laboratory College of Electrical Engineering&AutomationHenan Polytechnic University State Key Laboratory of Scientific&Engineering Computing Academy of Mathematics&Systems ScienceChinese Academy of Sciences

This paper introduces the concept of hierarchical-control-based output synchronization of coexisting attractor networks. Within the new framework, each dynamic node is made passive at first utilizing intra-control around its own arena. Then each dynamic node is viewed as one agent, and on account of that, the solution of output synchronization of coexisting attractor networks is transformed into a multi-agent consensus problem, which is made possible by virtue of local interaction between individual neighbours; this distributed working way of coordination is coined as inter-control, which is only specified by the topological structure of the network. Provided that the network is connected and balanced, the output synchronization would come true naturally via synergy between intra and inter-control actions, where the rightness is proved theoretically via convex composite Lyapunov functions. For completeness, several illustrative examples are presented to further elucidate the novelty and efficacy of the proposed scheme.

关键词： hierarchical control passive control composite Lyapunov function the Newton--Leipnik equation attractor

来源：评论

学校读者我要写书评

暂无评论

Order conditions of two kinds of canonical difference schemes

引用

Computers and Mathematics with Applications 1993年第6期25卷 61-74页

作者： Wen-Jie Zhu Meng-Zhao Qin State Key Laboratory of Scientific Engineering Computing Computing Center Academia Sinica Beijing 100080 China

The main purpose of this paper is to develop and simplify the general conditions for an s-stage explicit canonical difference scheme to be of qth order while the simplified order conditions for canonical RKN methods, ...

The main purpose of this paper is to develop and simplify the general conditions for an s-stage explicit canonical difference scheme to be of q^th order while the simplified order conditions for canonical RKN methods, which are applied to special kinds of second order ordinary differential equations, are also obtained here. © 1993.

关键词：

来源：评论

学校读者我要写书评

暂无评论

TWO-SCALE FINITE ELEMENT GREEN'S FUNCTION APPROXIMATIONS WITH APPLICATIONS TO ELECTROSTATIC POTENTIAL COMPUTATION

引用

Journal of Systems Science & Complexity 2010年第1期23卷 177-193页

作者： Ying YANG Aihui ZHOU Department of Computational Science and Mathematics Guilin University of Electronic Technology Guilin 541004 China. The State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China.

In this paper,a two-scale finite element approach is proposed and analyzed for approximationsof Green's function in *** approach is based on a two-scale finite elementspace defined,respectively,on the whole domain with size H and on some subdomain containing singularpoints with size h (h << H).It is shown that this two-scale discretization approach is very *** particular,the two-scale discretization approach is applied to solve Poisson-Boltzmann equationssuccessfully.

关键词： Error analysis finite element Green＇s function Poisson-Boltzmann equation two-scale.

来源：评论

学校读者我要写书评

暂无评论

Monotone projected gradient methods for large-scale box-constrained quadratic programming

引用

Science China Mathematics 2006年第5期49卷 688-702页

作者： ZHOU Bin, GAO Li & DAI Yuhong School of Mathematical Sciences and LMAM, Peking University, Beijing 100871, China State key laboratory of scientific and engineering computing, Institute of Computational Mathematics and scientific/engineering computing, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100080, China School of Mathematical Sciences LMAM Peking University Beijing 100871 China State Key Laboratory of Scientific Engineering Computing Institute of Computational Mathematics Scientific/Engineering Computing Academy of Mathematics Systems Science Chinese Academy of Sciences Beijing 100080 China

Inspired by the success of the projected Barzilai-Borwein (PBB) method for largescale box-constrained quadratic programming, we propose and analyze the monotone projected gradient methods in this paper. We show by experiments and analyses that for the new methods,it is generally a bad option to compute steplengths based on the negative gradients. Thus in our algorithms, some continuous or discontinuous projected gradients are used instead to compute the steplengths. Numerical experiments on a wide variety of test problems are presented, indicating that the new methods usually outperform the PBB method.

关键词： projected gradients, monotone gradient methods, box-constrained quadratic programming, large-scale problems.

来源：评论

学校读者我要写书评

暂无评论

A Parallel Algorithm for Adaptive Local Refinement of Tetrahedral Meshes Using Bisection

引用

Numerical Mathematics(Theory,Methods and Applications) 2009年第1期2卷 65-89页

作者： Lin-Bo Zhang State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China.

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 Chttp：//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 simukaneous 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 biseetioning refinement procedure.

关键词： Adaptive refinement bisection tetrahedral mesh parallel algorithm MPI.

来源：评论

学校读者我要写书评

暂无评论

Direct numerical simulation of transition and turbulence in compressible mixing layer

引用

Science China Mathematics 2000年第4期43卷 421-429页

作者：傅德薰马延文张林波 Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics and Specific/Engineering Computing Chinese Academy of Sciences Beijing 100080 China

The three-dimensional compressible Navier-Stokes equations are approximated by a fifth order upwind compact and a sixth order symmetrical compact difference relations combined with three-stage Ronge-Kutta method. The computed results are presented for convective Mach numberMc = 0.8 andRe = 200 with initial data which have equal and opposite oblique waves. From the computed results we can see the variation of coherent structures with time integration and full process of instability, formation of A -vortices, double horseshoe vortices and mushroom structures. The large structures break into small and smaller vortex structures. Finally, the movement of small structure becomes dominant, and flow field turns into turbulence. It is noted that production of small vortex structures is combined with turning of symmetrical structures to unsymmetrical ones. It is shown in the present computation that the flow field turns into turbulence directly from initial instability and there is not vortex pairing in process of transition. It means that for large convective Mach number the transition mechanism for compressible mixing layer differs from that in incompressible mixing layer.

关键词： compressible mixing layer transition turbulence compact scheme.

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：