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961.
962.
Fang Gui WANG Institute of Mathematics Software Science Sichuan Normal University Sichuan P.R.China 《数学研究与评论》2010,(3)
Let R be a domain and let R wg be the w-global transform of R.In this note it is shown that if R is a Mori domain,then the t-dimension formula t- dim(R wg ) = t- dim(R) - 1 holds. 相似文献
963.
Zhigao Shi Jinshan College Fujian Agriculture Forestry University Fuzhou 《Annals of Differential Equations》2010,(1):53-58
In this paper, a class of simplified Type-IV predator-prey system with linear state feedback is investigated. We prove the boundedness of the positive solutions to this system, and analyze the quality of the equilibria and the existence of limit cycles of the system surrounding the positive equilibra. By Hopf bifurcation theory, the result of having two limit cycles to the system is obtained. 相似文献
964.
THE EXISTENCE OF POSITIVE SOLUTIONS TO BOUNDARY VALUE PROBLEM OF SECOND ORDER DIFFERENTIAL EQUATIONS
Juan Dai Zongfu Zhou School of Mathematical Science Anhui University Hefei 《Annals of Differential Equations》2010,(1):10-15
In this paper, a fixed point theorem in C1[0,1] space is established using the properties of the fixed point index. This theorem is applied to prove the existence of positive solution to the boundary value problems of second order differential equations. 相似文献
965.
Moscow State University 《Differential Equations》2006,42(2):297-306
Chronicle
On the seminar on problems of nonlinear dynamics and control at Moscow State University 相似文献966.
967.
LIU Bin Laboratory of Mathematics its Applications School of Mathematical Sciences Peking University Beijing China 《中国科学 数学(英文版)》2010,(1)
We deal with the stability of zero solutions of planar Hamiltonian and reversible systems which are quasi-periodic in the time variable. Under some reasonable assumptionswe prove the existence of quasi-periodic solutions in a small neighborhood of zero solutions and the stability of zero solutions. 相似文献
968.
YANG YiDu ZHANG ZhiMin & LIN FuBiao School of Mathematics Computer Science Guizhou Normal University Guiyang China 《中国科学 数学(英文版)》2010,(1)
This is a survey article about using non-conforming finite elements in solving eigenvalue problems of elliptic operators,with emphasis on obtaining lower bounds. In addition,this article also contains some new materials for eigenvalue approximations of the Laplace operator,which include:1) the proof of the fact that the non-conforming Crouzeix-Raviart element approximates eigenvalues associated with smooth eigenfunctions from below;2) the proof of the fact that the non-conforming EQ rot1 element approximates eigenvalues from below on polygonal domains that can be decomposed into rectangular elements;3) the explanation of the phenomena that numerical eigenvalues λ 1,h and λ 3,h of the non-conforming Q rot1 element approximate the true eigenvalues from below for the L-shaped domain. Finally,we list several unsolved problems. 相似文献
969.
HE Yong SHUM KarPing & WANG ZhengPan Institute of Theories on Algebra Automaton School of Computer Science Technology Hunan University of Science Technology Xiangtan China 《中国科学 数学(英文版)》2010,(5)
A semigroup S with a sub-band B is called a good B-quasi-Ehresmann semigroup if it is a Bsemiabundant semigroup satisfying the congruence condition such that B((ab)+)abB((ab)*)aB(a*)B(b+)b for all a,b ∈S.We show that every good B-quasi-Ehresmann semigroup has a global representation and a standard representation.As a special case,the structure of good quasi-adequate semigroups is described. 相似文献
970.
ZHANG JunQiang & LI XianHua School of Mathematical Sciences Soochow University Suzhou China 《中国科学 数学(英文版)》2010,(5)
Let G be a finite p-group.If the order of the derived subgroup of each proper subgroup of G divides pi,G is called a Di-group.In this paper,we give a characterization of all D1-groups.This is an answer to a question introduced by Berkovich. 相似文献