检索结果-南通市图书馆

VISCOSITY METHOD OF A NON-HOMOGENEOUS BURGERS EQUATION

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2003年第4期23卷 567-576页

作者：丁夏畦丁毅 Institute of Applied mathematics Chinese Academy of Sciences Beijing 100080 China department of mathematics City University of New Jersey U.S.A.

In [1], Ding et al. studied the nonhomogeneous Burgers equationut + uuX = μ + 4x. (1.1)This paper will prove that when μ→0 the solution of (1.1) will approach the generalized solution ofut + uux = 4z. (1.2)The authors notice that the equation (1.2) is beyond the scope of investigations by OleinikO. in [2]. The solutions here are unbounded in general.The paper also studies the δ-wave phenomenon when (1.2) is jointed with some otherequation.

关键词： Burgers equation Hopf equation nonhomogeneous equation

Resonance between automorphic forms and exponential functions

在线全文

学校读者我要写书评

暂无评论

Science China mathematics 2010年第9期53卷 2463-2472页

作者： REN XiuMin1,& YE YangBo1,2 1school of mathematics,Shandong university,Jinan 250100,China 2department of mathematics,The university of Iowa,Iowa city,Iowa 52242-1419,usa school of mathematics Shandong University department of mathematics The University of Iowa

Let f be a holomorphic cusp form of weight k for SL2(Z) and λf(n) its n-th Fourier *** this paper,the exponential sum X 详细信息

Let f be a holomorphic cusp form of weight k for SL2(Z) and λf(n) its n-th Fourier *** this paper,the exponential sum X

关键词： automorphic form exponential sum resonance

AN INTERIOR TRUST REGION ALGORITHM FOR NONLINEAR MINIMIZATION WITH LINEAR CONSTRAINTS

在线全文

学校读者我要写书评

暂无评论

Journal of Computational mathematics 2002年第3期20卷 225-244页

作者： Jian-guo Liu (department of mathematics, university of North Texas, Denton, TX 76203, usa) department of mathematics University of North Texas 美国 Denton

Presents information on a study which analyzed an interior trust-region-based algorithm for linearly constrained minimization problems. Optimality conditions for the linearly constrained minimization problem presented; Vectors for each updating step in the algorithm proposed; Establishment of the convergence properties of the proposed algorithm.

关键词： Nonlinear programming Linear constraints Trust region algorithms newton methods Interior algorithms Quadratic convergence

Commercial Development Strategies and Operation at new york & new Jersey Ports

在线全文

学校读者我要写书评

暂无评论

上海海事大学学报 2004年第2期25卷 127-131页

作者： MU Lan(The Port Authority of new york & new Jersey) The Port Authority of new york&new Jersey

1 QuestionsWhere are we headed? What needs to be done? How will our plan be executed? I understand;? Where we are headed. ? What results must be produced. ? How we will measure progress and results. ? How I will contr... 详细信息

关键词： new Jersey Ports Commercial Development Strategies and Operation at new york will

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Finding the Mid-Path

Wuhan university Journal of Natural Sciences 2001年第Z1期6卷 83-99页

作者： Alice E. Fischer department of Computer Science, university of new Haven,West Haven CT 06516,usa department of Computer Science University of New Haven West Haven USA

Computers have changed nearly every aspect of life in this world. Invented roughly fifty years ago, they now form the infrastructure on which government, business, and global communications rest. As our reliance on computers increases, so does the number and complexity of the applications and the number and quality of trained professionals that will be needed to support further progress. The United States already faces personnel shortages in some computer related jobs, including university teaching. In the face of this evident and increasing need, we must think clearly about out expectations for computing professionals of all sorts and the way they are trained. In the forty years that I have been in the field, the focus in industry has changed from programming to software development. A gulf is growing between the skills that students build at a university and the needs of industry. This paper examines the nature and extent of the problem and suggests a variety of ways to address it

关键词： curriculum gap internship professional competence professional training

Polynomials,Higher Order Sobolev Extension Theorems and Interpolation Inequalities on Weighted Folland-Stein Spaces on Stratified Groups

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2000年第3期16卷 405-444页

作者： Guozhen Lu department of mathematics,Wayne State university,Detroit,MI 48202,usa department of mathematics Wayne State University Detroit USA

This paper consists of three main *** of them is to develop local and global Sobolev interpolation inequalities of any higher order for the nonisotropic Sobolev spaces on stratified nilpotent Lie *** the extensive research after Jerison’s work[3]on Poincaré-type inequalities for Hrmander’s vector fields over the years,our results given here even in the nonweighted case appear to be *** interpolation inequalities have crucial applications to subelliptic or parabolic PDE’s involving vector *** main tools to prove such inequalities are approximating the Sobolev func- tions by polynomials associated with the left invariant vector fields on *** very useful properties for polynomials associated with the functions are given here and they appear to have independent interests in their own *** the existence of such polynomials is the second main part of this *** results of these two parts have been announced in the author’s paper in Mathematical Research Letters[38]. The third main part of this paper contains extension theorems on anisotropic Sobolev spaces on stratified groups and their applications to proving Sobolev interpolation inequalities on(εδ)domains. Some results of weighted Sobolev spaces are also given *** construct a linear extension operator which is bounded on different Sobolev spaces *** particular,we are able to construct a bounded linear extension operator such that the derivatives of the extended function can be controlled by the same order of derivatives of the given Sobolev *** are stated and proved for weighted anisotropic Sobolev spaces on stratified groups.

关键词： Poincaré inequalities Extension theorems Interpolation inequalities Anisotropic Sobolev spaces A_p weights (ε,δ)domains Vector fields Polynomials on stratified groups

Discrete Calderón-type Reproducing Formula

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2000年第2期16卷 277-294页

作者： Yongsheng Han department of mathematics,Auburn university,Auburn,Alabama 36849-5310,usa department of mathematics Auburn University Auburn Alabama 36849-5310 USA

In this paper we use the Calderón-Zygmund operator theory to provide a discrete Calderón- type reproducing *** translation,dilation and,in particular,the Fourier transform are never used in the proofs,all results still hold on spaces of homogeneous type introduced by Coifman and Weiss. As a consequence,we obtain a class of frames with the minimum regularity properties.

关键词： Spaces of homogeneous type Calderón reproducing formula Frame

Tree wavelet approximations with applications

在线全文

学校读者我要写书评

暂无评论

Science China mathematics 2005年第5期48卷 680-702页

作者： XU Yuesheng & ZOU Qingsong department of mathematics, Syracuse university, Syracuse, ny 13244, usa Institute of mathematics, Academy of mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100080, China department of Scientific Computing and Computer Science, Zhongshan university, Guangzhou 510275, China department of mathematics Syracuse University Syracuse USA Institute of mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China department of Scientific Computing and Computer Science Zhongshan University Guangzhou China

We construct a tree wavelet approximation by using a constructive greedy scheme (CGS). We define a function class which contains the functions whose piecewise polynomial approximations generated by the CGS have a prescribed global convergence rate and establish embedding properties of this class. We provide sufficient conditions on a tree index set and on bi-orthogonal wavelet bases which ensure optimal order of convergence for the wavelet approximations encoded on the tree index set using the bi-orthogonal wavelet bases. We then show that if we use the tree index set associated with the partition generated by the CGS to encode a wavelet approximation, it gives optimal order of convergence.

关键词： greedy algorithms tree wavelet approximations Besov spaces.

SYMPLECTIC SCHEMES FOR QUASILINEAR WAVE EQUATIONS OF KLEIN-GORDON AND SINE-GORDON TYPE

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Computational mathematics 2001年第5期19卷 475-488页

作者： Xiao-wu Lu (department of mathematics and Computer Science, Emory university, Atlanta, GA 30322, usa) Emory university 美国 30322

Presents a class of finite difference methods of first and second order accuracy for the computation of solutions to the quasilinear wave equations. Overview of general symplectic schemes and generating functional; Nu... 详细信息

关键词： Symplectic integration Sine-Gordon equations Finite difference method.