检索结果-南通市图书馆

Ritt's theorem and the Heins map in hyperbolic complex manifolds

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2005年第Z1期48卷 238-243页

作者： Marco Abate Filippo Bracci Dipartimento di Matematica Università di Pisa Largo Pontecorvo 556127 PisaItalyDipartimento di Matematica Università di Roma "Tor Vergata"Via della Ricerca Scientifica00133 RomaItaly

Let X be a Kobayashi hyperbolic complex manifold, and assume that X does not contain compact complex submanifolds of positive dimension (e.g., X Stein). We shall prove the following generalization of Ritt's theorem: every holomorphic self-map f: X →X such that f(X) is relatively compact in X has a unique fixed point τ(f) ∈ X, which is attracting. Furthermore, we shall prove that τ(f) depends holomorphically on f in a suitable sense, generalizing results by Heins, Joseph-Kwack and the second author.

关键词： holomorphic self-map, fixed point, Wolff point, Ritt's theorem, Heins map, Stein manifold.

Maschke-type theorem and Morita context over weak Hopf algebras

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2006年第5期49卷 587-598页

作者： ZHANG Liangyun College of Science, Nanjing Agricultural University, Nanjing 210095, China Department of Mathematics, Nanjing University, Nanjing 210008, China College of Science Nanjing Agricultural University Nanjing China Department of Mathematics Nanjing University Nanjing China

This paper gives a Maschke-type theorem over semisimple weak Hopf algebras,extends the well-known Maschke-type theorem given by Cohen and Fishman and constructs a Morita context over weak Hopf algebras.

关键词： weak Hopf algebra, smash product, Maschke-type theorem, Morita context.

Stone's representation theorem in fuzzy topology

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2003年第6期46卷 775-788页

作者：刘应明张德学 Department of Mathematics Sichuan University Chengdu 610064 China Correspondence should be addressed to Liu Yingming

In this paper, a complete solution to the problem of Stone's repesentation theorem in fuzzy topology is given for a class of completely distributive lattices. Precisely, it is proved that if L is a frame such that 0 ∈ L is a prime or 1 ∈ L is a coprime, then the category of distributive lattices is dually equivalent to the category of coherent L-locales and that if L is moreover completely distributive, then the category of distributive lattices is dually equivalent to the category of coherent stratified L-topological spaces.

关键词： distributive lattice, L-topological space, Stone's representation theorem, frame.

A note on the uniqueness theorem of meromorphic mappings

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2006年第3期49卷 360-365页

作者： YAN Qiming CHEN Zhihua Department of Mathematics Tongji University Shanghai 200092 China Department of Mathematics Tongji University Shanghai 200092 China

In this article, some uniqueness theorems of meromorphic mappings are proved.

关键词： value distribution theory, uniqueness theorem, meromorphic mappings.

Boundary value problems of discrete generalized Emden-Fowler equation

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2006年第10期49卷 1303-1314页

作者： YU Jianshe GUO Zhiming College of Mathematics and Information Sciences Guangzhou University Guangzhou 510006 China College of Mathematics and Information Sciences Guangzhou University Guangzhou 510006 China

By using the critical point theory, some sufficient conditions for the existence of the solutions to the boundary value problems of a discrete generalized Emden-Fowler equation are obtained. In a special case, a sharp condition is obtained for the existence of the boundary value problems of the above equation. For a linear case, by the discrete variational theory, a necessary and sufficient condition for the existence, uniqueness and multiplicity of the solutions is also established.

关键词： discrete generalized Emden-Fowler equation, boundary value problem, Saddle Point theorem, discrete variational theory.

The Roper-Suffridge extension operator and classes of biholomorphic mappings Dedicated to Professor Sheng GONG on the occasion of his 75th birthday

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2006年第11期49卷 1539-1552页

作者： GRAHAM Ian KOHR Gabriela Department of Mathematics University of Toronto TorontoOntario M5S 2E4Canada Faculty of Mathematics and Computer Science Babes-Bolyai University 1 M. Kogǎlniceanu Str. 400084 Cluj-NapocaRomania

In this paper we give a survey about the Roper-Suffridge extension operator and the developments in the theory of univalent mappings in several variables to which it has led. We begin with the basic geometric properties (most of which now have a number of different proofs)and discuss relations with the theory of Loewner chains and generalizations and modifications of the operator, some of which are very recent.

关键词： convex mapping, starlike mapping, Roper-Suffridge operator, growth theorem, distortion theorem, covering theorem, Loewner chain, parametric representation,extreme points, linear invariant family.

New characterizations of Hajlasz-Sobolev spaces on metric spaces

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2003年第5期46卷 675-689页

作者：杨大春 Department of Mathematics. Beijing Normal University Beijing 100875 China

This paper introduces the fractional Sobolev spaces on spaces of homogeneous type, including metric spaces and fractals. These Sobolev spaces include the well-known Hajtasz-Sobolev spaces as special models. The author establishes various characterizations of (sharp) maximal functions for these spaces. As applications, the author identifies the fractional Sobolev spaces with some Lipscitz-type spaces. Moreover, some embedding theorems are also given.

关键词： Sobolev space, Lipschitz-type space, embedding theorem, maximal function, space ofhomogeneous type.

Estimation of the Bezout number for piecewise algebraic curve

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2003年第5期46卷 710-717页

作者：王仁宏许志强 Institute of Mathematical Sciences Dalian University of Technology Dalian 116024 China Correspondence should be addressed to Xu Zhiqiang

A piecewise algebraic curve is a curve determined by the zero set of a bivariate spline *** this paper, a conjecture on triangulation is confirmed. The relation between the piecewise linear algebraiccurve and four-color conjecture is also presented. By Morgan-Scott triangulation, we will show the instabilityof Bezout number of piecewise algebraic curves. By using the combinatorial optimization method, an upperbound of the Bezout number defined as the maximum finite number of intersection points of two piecewisealgebraic curves is presented.

关键词： piecewise algebraic curve, bezout theorem, triangulation, bivariate splines.

SIMULTANEOUS DIOPHANTINE APPROXIMATION

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 1991年第10期34卷 1153-1161页

作者：王连祥 Institute of Mathematics. Acadcmia Sinica Beijing 100080 PRC

In this paper we give several existence and effective results for theorems of Dirichletand Minkowski on simultaneous Diophantine approximation in the homogeneous case (includingp-adic and p-adic-real mixed cases).

关键词： Diophantine approximation Diricblet theorem, basis reduction algorithm.