检索结果-南通市图书馆

Short cycle structures for graphs on surfaces and an open problem of Mohar and Thomassen

在线全文

学校读者我要写书评

暂无评论

Science china mathematics 2006年第2期49卷 212-224页

作者： REN Han & DENG Mo department of mathematics, East china {3. University, Shanghai 200062, china College of mathematics & Information Science, Northwest {3. University, Lanzhou 73.070, china department of mathematics East China Normal University Shanghai China College of mathematics & Information Science Northwest Normal University Lanzhou China

In this paper we investigate cycle base structures of a (weighted) graph and show that much information of short cycles is contained in an MCB (i.e., minimum cycle base). After setting up a Hall type theorem for base-transformation, we give a sufficient and necessary condition for a cycle base to be an MCB. Furthermore, we show that the structure of MCB in a (weighted)graph is unique. The property is also true for those having a longest length (although much work has been down in evaluating MCB, little is known for those having a longest length). We use those methods to find out some unknown properties for short cycles sharing particular properties in (unweighted) graphs. As applications, we determine the structures of short cycles in an embedded graph and show that there exist polynomially bounded algorithms in finding a shortest contractible cycle and a shortest two-sided cycle provided such cycles exist. Those answer an open problem of B. Mohar and C. Thomassen.

关键词： cycle base facial cycle graph embedding.

METHOD OF NONCONFORMING MIXED FINITE ELEMENT FOR SECOND ORDER ELLIPTIC PROBLEMS METHOD OF NONCONFORMING MIXED FINITE ELEMENT FOR SECOND ORDER ELLIPTIC PROBLEMS

在线全文

学校读者我要写书评

暂无评论

Journal of Computational mathematics 2000年第5期18卷 449-456页

作者： Zhen-dong Luo (department of mathematics, Capital normal University, Beijing 100057, {3.) 首都师范大学北京 100037

In this paper, the method of non-conforming mixed finite element for second order elliptic problems is discussed and a format of real optimal order for the lowest order error estimate.

关键词： Non-conforming mixed finite element Error estimate Second order elliptic problems.

Lp integrability of trigonometric series with special varying coefficients

在线全文

学校读者我要写书评

暂无评论

Applied mathematics:A Journal of Chinese Universities 2009年第4期24卷 402-410页

作者： WEI Bao-rong department of mathematics,Hangzhou normal University,Zhejiang 3.003.,{3. department of mathematics Hangzhou Normal University Zhejiang China

Very recently,Yu,Le and Zhou introduced the so called Δ*B1 and Δ*B2 conditions,which are generalizations of the monotone *** applying these two new conditions,the author essentially generalizes the classical results of Chen on the necessary and sufficient conditions of the Lp integrability of trigonometric *** fact,the present paper gives the first result on the necessary and sufficient conditions of the Lp integrability of trigonometric series,where coefficients may have diffierent signs.

关键词： Lp integrability trigonometric series special varying coefficients

DERIVATIONS ON DIFFERENTIAL OPERATOR ALGEBRA AND WEYL ALGEBRA

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 1996年第2期17卷 199-212页

作者： CHEN CAOYU department of mathematics, Shanghai normal University, Shanghai 20023., {3.. 上海师范大学数学系上海

Let L be an n-dimensional nilpotent Lie algebra with a basis {x1,…,xn}, and every xiacts as a locally nilpotent derivation on algebra A. This paper shows that there exists a setof derivations {y1,…,yn} on U(L) such that (A#U(L))#k[yi,…,yn] is isomorphic to theWeyl algebra An(A). The author also uses the derivations to obtain a necessary and sufficientcondition for a finite dimensional Lie algebra to be nilpotent.

关键词： Crossed porduct Smash product Derivation Nilpotent Lie algebra Weyl algebra

Recovery of functions via their irregular sampling values

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第4期43卷 268-271页

作者： FANG Gensun department of mathematics, Beijing normal University, Beijing 100875, {3. department of mathematics Lkijing Normal University Beijing China

It is proved that if a function can be completely reconstructed by tempered splines which satisfy the real Kiesz basis condition as the degree of spline goes to infinity, then the function is band limited.

关键词： band limited function cardinal splines irregular sampling.

Cartesian closedness of categories of completely distributive lattices

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第24期43卷 2059-2063页

作者： ZHANG Dexue 1 and YANG Zhongqiang 2 1. department of mathematics, Sichuan University, Chengdu 610064, china 2. department of mathematics, Shaanxi normal University, Xi’an 710062, china department of mathematics Sichuan University Chengdu China department of mathematics Shaanxi Normal University Xi’an China

The category of completely distributive lattices with Scott continuous functions is cartesian closed. Neither the category of completely distributive lattices with arbitrary union preserving mappings nor the category ... 详细信息

关键词： completely distributive lattice continuous lattice cartesian closedness.

A new definition of restricted Lie superalgebras

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2000年第4期45卷 316-321页

作者： WANG Ying & ZHANG Yongzheng1. department of mathematics, Harbin Institute Technology, Harbin 150001, china 2. department of mathematics, Northeast normal University, Changchun 13.024, china department of mathematics Harbin Institute Technology Harbin China department of mathematics Northeast Normal University Changchun China

A new definition of restricted Lie superalgebras has been given; some important results on the representation theory of restricted Lie superalgebra have been obtained.

关键词： restricted Lie superalgebra p-mapping p-semilinear mapping α-representation.

Moment bounds for IID sequences under sublinear expectations

在线全文

学校读者我要写书评

暂无评论

Science china mathematics 2011年第10期54卷 2155-2160页

作者： HU Feng1,2 1department of mathematics,Qufu normal University,Qufu 273.65,{3. 2School of mathematics,Shandong University,Jinan 250100,{3. department of mathematics Qufu Normal University Qufu China School of mathematics Shandong University Jinan China

With the notion of independent identically distributed(IID) random variables under sublinear expectations introduced by Peng,we investigate moment bounds for IID sequences under sublinear expectations. We obtain a moment inequality for a sequence of IID random variables under sublinear expectations. As an application of this inequality,we get the following result:For any continuous functionsatisfying the growth condition |(x) | C(1 + |x|p) for some C > 0,p 1 depending on ,the central limit theorem under sublinear expectations obtained by Peng still holds.

关键词： moment bound sublinear expectation IID random variables G-normal distribution central limit theorem

SUPERCONVERGENCE ANALYSIS FOR CUBIC TRIANGULARELEMENT OF THE FINITE ELEMENTSUPERCONVERGENCE ANALYSIS FOR CUBIC TRIANGULARELEMENT OF THE FINITE ELEMENT

在线全文

学校读者我要写书评

暂无评论

Journal of Computational mathematics 2000年第5期18卷 541-550页

作者： Qi-ding Zhu (department of mathematics, Hunan normal University, Changsha 410081, {3. ) 湖南师范大学湖南长沙 410081

In this paper, we construct a projection interpolation for cubic triangular element by using othogonal expansion triangular method. We show two fundamental formulas of estimation on a special partion and obtain a superconvergence result of 1- ∈order higher for the placement function and its tangential derivative on the third order Lobatto points and Gauss points on each edge of triangular element.

关键词： Finite element Superconvergence Projection interpolation.