Lanczos方法解大型矩阵逆谱问题的稳定性

Ｌａｎｃｚｏｓ方法解大型矩阵逆谱问题的稳定性朱本仁，王桂松（山东大学）ＳＴＡＢＩＬＩＴＹＯＦＴＨＥＬＡＮＣＺＯＳＡＬＧＯＲＩＴＨＭＩＮＳＯＬＶＩＮＧＬＡＲＧＥＩＮＶＥＲＳＥＳＰＥＣＴＲＡＬＰＲＯＢＬＥＭＳ￥ＺｈｕＢｅｎ－ｒｅｎ；ＷａｎｇＧｕｉ－ｓｏｎ...     

非协调元的一个Sobolev嵌入定理

非协调元的一个Ｓｏｂｏｌｅｖ嵌入定理冯康，王烈衡（中国科学院计算中心）ＡＳＯＢＯＬＥＶＩＭＢＥＤＤＩＮＧＴＨＥＯＲＥＭＦＯＲＮＯＮＣＯＮＦＯＲＭＩＮＧＦＩＮＩＴＥＥＬＥＭＥＮＴＳＰＡＣＥＳ￥ＦｅｎｇＫａｎｇ；ＷａｎｇＬｉｅ－ｈｅｎｇ（Ｃｏｍｐｕｔｉｎ...     

非协调元的分数阶Sobolev空间

非协调元的分数阶Ｓｏｂｏｌｅｖ空间冯康，王烈衡（中科院计算中心）ＦＡＣＴＩＯＮＡＬＯＲＤＥＲＳＯＢＯＬＥＶＳＡＣＥＳＦＯＲＮＯＮＣＯＮＦＯＲＭＩＮＧＦＩＮＩＴＥＥＬＥＭＥＮＴＳ￥ＦｅｎｇＫａｎｇ；ＷａｎｇＬｉｅ－ｈｅｎｇ（ＣｏｍｐｕｔｉｎｇＣｅｎｔｅ...     

A SIMPLE PROOF OF THE INEQUALITY MFFD（L）≤（71／60）OPT（L）＋1，L FOR THE MFFD BIN－PACKING ALGORITHM

ＡＳＩＭＰＬＥＰＲＯＯＦＯＦＴＨＥＩＮＥＱＵＡＬＩＴＹＭＦＦＤ（Ｌ）≤（７１／６０）ＯＰＴＬ）＋１，ＬＦＯＲＴＨＥ　ＭＦＦＤＢＩＮ－ＰＡＣＫＩＮＧＡＬＧＯＲＩＴＨＭＹＵＥＭＩＮＹＩ（越民义）（ＩｎｓｔｉｔｕｔｅｏｆＡｐｐｌｉｅｄＭａｔｈｅｍａｔｉｃｓ...     

基于非协调元的区域分解法

基于非协调元的区域分解法戴培良，沈树民（常熟高专）（苏州大学）ＡＤＯＭＡＩＮＤＥＣＯＭＰＯＳＩＴＩＯＮＭＥＴＨＯＤＢＡＳＥＤＯＮＮＯＮＣＯＮＦＯＲＭＩＮＧＦＩＮＩＴＥＥＬＥＭＥＮＴＳ￥ＤａｉＰｅｉ－ｈａｎｇ；ＳｈｅｎＳｈｕ－ｍｉｎ（ＣｈａｎｇｓｈｕＣ...     

RANDOM ITERAtION OF HOLOMORPHIC SELF-MAPS OVER BOUNDED DOMAINS IN C~N

ＲＡＮＤＯＭＩＴＥＲＡＴＩＯＮＯＦＨＯＬＯＭＯＲＰＨＩＣＳＥＬＦ－ＭＡＰＳＯＶＥＲＢＯＵＮＤＥＤＤＯＭＡＩＮＳＩＮＣ~Ｎ￥ＺＨＡＮＧＷＥＮＪＵＮ；ＲＥＮＦＵＹＡＯ（ＤｅｐａｒａｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＨｅｎａｌＵｎｉｖｅｒｓｉｔｙｔＫａ?..     

线性流形上实对称半正定阵的一类逆特征值问题

线性流形上实对称半正定阵的一类逆特征值问题廖安平，郭忠（湖南大学应用数学系）ＡＣＬＡＳＳＯＦＩＮＶＥＲＳＥＥＩＧＥＮＶＡＬＵＥＰＲＯＢＬＥＭＳＦＯＲＲＥＡＬＳＹＭＭＥＴＲＩＣＳＥＭＩ－ＰＯＳＩＴＩＶＥＤＥＦＩＮＩＴＥＯＮＡＬＩＮＥＡＲＭＡＮＩＦＯＬＤ...     

计算周期解的Lagrange－鞍点算法

计算周期解的Ｌａｇｒａｎｇｅ－鞍点算法张锁春，康羽（中国科学院应用数学研究所）ＬＡＧＲＡＮＧＥ－ＳＡＤＤＬＥＰＯＩＮＴＡＬＧＯＲＩＴＨＭＯＦＣＯＭＰＵＴＡＴＩＮＧＰＥＲＩＯＤＩＣＳＯＬＵＴＩＯＮ￥ＺｈａｎｇＳｕｏ－ｃｈｕｎ；ＫｕｎｇＹｕ（Ｉｎｓｔｉｔ...     

分支问题中转接解支的开折方法

分支问题中转接解支的开折方法朱正佑，丛玉豪（兰州大学数学系）ＴＨＥＵＮＦＯＬＤＩＮＧＴＥＣＨＮＩＱＵＥＦＯＲＳＷＩＴＣＨＩＮＧＳＯＬＵＴＩＯＮＢＲＡＮＣＨＥＳＩＮＢＩＦＵＲＣＡＴＩＯＮＰＲＯＢＬＥＭＳ￥ＺｈｕＺｈｅｎｇ－ｙｏｕ；ＣｏｎｇＹｕ－ｈａｏ（...     

NEWTON－KANTOROVICH ITERATION METHOD FOR SOLVING INVERSE PROBLEMS OF NONLINEAR PARABOLIC SYSTEMS

ＮＥＷＴＯＮ－ＫＡＮＴＯＲＯＶＩＣＨＩＴＥＲＡＴＩＯＮＭＥＴＨＯＤＦＯＲＳＯＬＶＩＮＧＩＮＶＥＲＳＥＰＲＯＢＬＥＭＳＯＦＮＯＮＬＩＮＥＡＲＰＡＲＡＢＯＬＩＣＳＹＳＴＥＭＳＹｕＷｅｎｈｕａｎ（喻文焕）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，Ｔ...     

On the solution of Maxwell's equations in polygonal domains

This paper is concerned with the structure of the singular and regular parts of the solution of time‐harmonic Maxwell's equations in polygonal plane domains and their effective numerical treatment. The asymptotic behaviour of the solution near corner points of the domain is studied by means of discrete Fourier transformation and it is proved that the solution of the boundary value problem does not belong locally to H² when the boundary of the domain has non‐acute angles. A splitting of the solution into a regular part belonging to the space H², and an explicitly described singular part is presented. For the numerical treatment of the boundary value problem, we propose a finite element discretization which combines local mesh grading and the singular field methods and derive a priori error estimates that show optimal convergence as known for the classical finite element method for problems with regular solutions. Copyright © 2006 John Wiley & Sons, Ltd.     

一种高精度的裂纹奇异单元

基于广义伽辽金法的多变量有限元算法,增加了连续体力学有限元模型建立的灵活性.本文利用它,通过数值试验的对比建立了一种高精度的含奇异性的裂纹单元,并对多变量奇异元的构成进行了探讨.     

Diffeomorphism classification of finite group actions on disks

In this paper we discuss the diffeomorphism classification of finite group actions on disks. We answer the question when an action on a space M can be extended to an action on a disk such that the action is free away from M. Let the singular set consist of the points with nontrivial isotropy group. We show (under some dimension assumptions) that disks with diffeomorphic neighborhoods of the singular set can be imbedded into each other. As a consequence we find a classification of group actions on disks in terms of the neighborhood of the singular set and an element in the Whitehead group of G.     

Three Dimensional Interface Problems for Elliptic Equations

The author studies the structure of solutions to the interface problems for second order linear elliptic partial differential equations in three space dimension.The set of singular points consists of some singular lines and some isolated singular points.It is proved that near a singular line or a singular point,each weak solution can be decomposed into two parts,a singular part and a regular part.The singular parts are some finite sum of particular solutions to some simpler equations,and the regular parts are bounded in some norms,which are slightly weaker than that in the Sobolev space H~2.     

一类带弱奇异核非线性偏积分微分方程的全离散有限元

1引言我们将研究下面一类带弱奇异核非线性偏积分微分方程的数值解:u_t-▽·(a(u)▽u)-integral from n=0 to tβ(t-s)△u(s)ds=f(u),x∈Ω,t∈(?),(1.1) u(·,t)=0,x∈(?)Ω,t∈J,(1.2) u(·,0)=v(x),x∈Ω,(1.3)其中Ω为平面上的凸角域,J=(0,T],α和f为R上的光滑函数,满足0相似文献   

Numerical analysis of a non‐singular boundary integral method: Part I. The circular case

In order to numerically solve the interior and the exterior Dirichlet problems for the Laplacian operator, we present here a method which consists in inverting, on a finite element space, a non‐singular integral operator. This operator is a geometrical perturbation of the Steklov operator, and we precisely define the relation between the geometrical perturbation and the dimension of the finite element space, in order to obtain a stable and convergent scheme. Furthermore, this numerical scheme does not give rise to any singular integral. The scheme can also be considered as a special quadrature formula method for the standard piecewise linear Galerkin approximation of the weakly singular single layer potential, the special quadrature formula being defined by the introduction of a neighbouring curve. In the present paper, we prove stability and we give error estimates of our numerical scheme when the Laplace problem is set on a disk. We will extend our results to any domains by using compact perturbation arguments, in a second paper. Copyright © 2001 John Wiley & Sons, Ltd.     

Numerical analysis of a non‐singular boundary integral method: Part II: The general case

In order to numerically solve the interior and the exterior Dirichlet problems for the Laplacian operator, we have presented in a previous paper a method which consists in inverting, on a finite element space, a non‐singular integral operator for circular domains. This operator was described as a geometrical perturbation of the Steklov operator, and we have precisely defined the relation between the geometrical perturbation and the dimension of the finite element space, in order to obtain a stable and convergent scheme in which there are non‐singular integrals. We have also presented another point of view under which the method can be considered as a special quadrature formula method for the standard piecewise linear Galerkin approximation of the weakly singular single‐layer potential. In the present paper, we extend the results given in the previous paper to more general cases for which the Laplace problem is set on any ??^∞ domains. We prove that the properties of stability and convergence remain valid. Copyright © 2002 John Wiley & Sons, Ltd.     

A new rotated nonconforming pyramid element

In this paper, a new nonparametric nonconforming pyramid finite element is introduced. This element takes the five face mean values as the degrees of the freedom and the finite element space is a subspace of P₂. Different from the other nonparametric elements, the basis functions of this new element can be expressed explicitly without solving linear systems locally, which can be achieved by introducing a new reference pyramid. To evaluate the integration, a class of new quadrature formulae with only two/three equally weighted points on pyramid are constructed. We present the error estimation in the presence of quadrature formulae. Numerical results are shown to confirm the optimality of the convergence order for the second order elliptic problems.     

A note on the singular linear system of the generalized finite element methods

We characterize the kernel of the global stiffness matrix in the singular linear system of the generalized finite element methods (GFEM) which uses the classical finite element (FE) shape functions and local approximation space of harmonic polynomials.     

抛物方程初边值问题连续有限元的超收敛性

研究了一类一维抛物方程初边值问题的连续有限元方法.在空间上进行任意m次有限元半离散,在时间方向上进行二次连续有限元后,获得了一个稳定的全离散计算格式.利用单元分析法校正技术的新思想进行理论分析,连续有限元解在剖分网格节点上具有超收敛性.