检索结果-南通市图书馆

ON MULTIPLE POSITIVE SOLUTIONS FOR A NONLINEAR ELLIPTIC PROBLEM IN R^N

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Annals of mathematics,Series B 2000年第3期21卷 351-358页

作者： YANG HAITAO(department of mathematics, zhejiang University, {2., china.) WU SHAOPING(department of mathematics, zhejiang University, {2., china.) department of mathematics Zhejiang University Hangzhou 310027 China

By making use of Variational method, the authors obtain some results about existence of multiple positive solutions and their asymptotic behavior as the parameter →＋∞ for a semilinear elliptic problem in RN.

关键词： Critical point Asymptotic behavior Concentration

Online uniform machine covering with the known largest size

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2007年第11期17卷 1271-1278页

作者： Cao Shunjuan1,2.and Tan Zhiyi1,3(1. department of mathematics, zhejiang University, {2., china 2. department of mathematics, zhejiang Forestry University, hangzhou 311300, china 3. State Key Laboratory of CAD & CG, zhejiang University, {2., china) department of mathematics Zhejiang University Hangzhou 310027 China department of mathematics Zhejiang Forestry University Hangzhou 311300 China State Key Laboratory of CAD & CG Zhejiang University Hangzhou 310027 China

This paper investigates the semi-online scheduling problem with the known largest size on two uniform machines. The objective is to maximize the minimum machine completion time. Both lower bounds and algorithms are given. Algorithms are optimal for the majority values of s≥1, where s is the speed ratio of the two machines. The largest gap between the competitive ratio and the lower bound is about 0.064. Moreover, the overall competitive ratio 2.matches the overall lower bound.

关键词： scheduling and covering uniform machine design and analysis of algorithm online competitive ratio

Perturbations of the radical of nest algebras

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第7期43卷 556-560页

作者： LU Fangyan 1 and LU Shijie 2.1. department of mathematics, Suzhou University, Suzhou 2.5006, china 2. department of mathematics, zhejiang University, hangzhou 310027, china department of mathematics Suzhou University Suzhou China department of mathematics Zhejiang University Hangzhou China

Let R N and K-N be the radical ideal and the compact operator ideal of nest algebra T(N) respectively. It is proved thatR-N+K-N=span{T∈T(N)∶TT(N)NCT}=span{T∈T(N): #σ′(ST)≤1, S∈T(N)}.

关键词： nest algebras radical perturbation.

REMARKS ON h-TRANSFORM AND DRIFT

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of mathematics,Series B 1998年第4期19卷 473-478页

作者： YING JIANGANG (department of mathematics, zhejiang University, {2., china.) zhejiang Univ Dept Math Hangzhou 310027 Peoples R China

The author studies the h-transforms of symmetric Markov processes and corresponding Dirichlet spaces, and also discusses the drift transformation of Fukushima and Takeda’s type[2. and improves their result by a diffe... 详细信息

关键词： Right processes Revuz measures h-transform

Circular β ensembles,CMV representation,characteristic polynomials

在线全文

学校读者我要写书评

暂无评论

Science china mathematics 2009年第7期52卷 1467-1477页

作者： SU ZhongGen department of mathematics,zhejiang University,{2.,china 1. department of mathematics Zhejiang University Hangzhou 310027 China

In this note we first briefly review some recent progress in the study of the circular β ensemble on the unit circle,where β > 0 is a model *** the special cases β = 1,2.and 4,this ensemble describes the joint probability density of eigenvalues of random orthogonal,unitary and sympletic matrices,*** general β,Killip and Nenciu discovered a five-diagonal sparse matrix model,the CMV *** representation is new even in the case β = 2.and it has become a powerful tool for studying the circular β *** then give an elegant derivation for the moment identities of characteristic polynomials via the link with orthogonal polynomials on the unit circle.

关键词： characteristic polynomials circular β ensembles CMV representation moment identity 15A52

Lipschitz continuity of best approximations and Chebyshev centers

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第3期43卷 185-188页

作者： LI Chong 1 and WANG Xinghua 2.1. Center for Mathematical Sciences, zhejiang University, hangzhou 310027, {2. 2. department of mathematics, hangzhou University, hangzhou 31002., {2. Center for Mathematical Sciences Zhejiang University Hangzhou China department of mathematics Hangzhou University Hangzhou China

The Lipschitz continuity results are given for best approximations and Chebyshev centers. Consequently, the open problem presented by Septycki and Vleck is solved completely.

关键词： best approximation Chebyshev center uniform convexity.

Rigidity for rational maps with Cantor Julia sets

在线全文

学校读者我要写书评

暂无评论

Science china mathematics 2008年第1期51卷 79-92页

作者： ZHAI Yu department of mathematics, zhejiang University, {2., china department of mathematics Zhejiang University Hangzhou 310027 China

In this paper, we prove that two rational maps with the Cantor Julia sets are quasicon- formally conjugate if they are topologically conjugate.

关键词： Cantor Julia set rigidity puzzle piece bounded shape quasiconformally conjugate 37F12

Local orthogonal transform for a class of acoustic waveguides

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2007年第10期17卷 1136-1146页

作者： Zhu Jianxin and Li Peng(department of mathematics, zhejiang University, {2., china) department of mathematics Zhejiang University Hangzhou 310027 China

There are some curved interfaces in acoustic waveguides. To compute wave propagation along the waveguides with some marching methods, flattening of the internal interfaces is needed. In this paper, a local orthogonal coordinate transform and an equation transform are constructed to solve the two-dimensional Helmholtz equation for the waveguides bounded by a flat top, a flat bottom and two curved internal interfaces with three layered media. The curved internal interfaces are flattened by the local orthogonal coordinate transform, and the corresponding transformed Helmholtz equation can be solved by some marching methods. This treatment can be extended in multilayered medium waveguides. The one-way reformulation based on the Dirichlet-to-Neumann (DtN) map is then used to reduce the boundary value problem to an initial value problem. Numerical implementation of the resulting operator Riccati equation uses a large range step method to discretize the range variable and a truncated local eigenfunction expansion to approximate the operators. This method is particularly useful for solving long range wave propagation problems in slowly varying waveguides with multilayered medium structure.

关键词： Helmholtz equation local orthogonal transform DtN reformulation marching method internal interface one-way reformulation.

Mean size formula of wavelet subdivision tree on Heisenberg group

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Applied mathematics(A Journal of Chinese Universities) 2008年第3期23卷 303-312页

作者： WANG Guo-mao department of mathematics,zhejiang University,{2.,china department of mathematics,hangzhou Dianzi University,hangzhou 310018,china. department of mathematics Zhejiang University Hangzhou 310027 China department of mathematics Hangzhou Dianzi University Hangzhou 310018 China

The purpose of this paper is to investigate the mean size formula of wavelet packets （wavelet subdivision tree） on Heisenberg group. The formula is given in terms of the p-norm joint spectral radius. The vector refinement equations on Heisenberg group and the subdivision tree on the Heisenberg group are discussed. The mean size formula of wavelet packets can be used to describe the asymptotic behavior of norm of the subdivision tree.

关键词： Heisenberg group wavelet packets subdivision tree joint spectral radius stability