INVERSE EIGENVALUE PROBLEM OF HERMITIAN GENERALIZED ANTI-HAMILTONIAN MATRICES

§1　IntroductionWe considerthe following inverse eigenvalue problem offinding an n-by-n matrix A∈S such thatAxi =λixi,i =1,2 ,...,m,where S is a given set of n-by-n matrices,x1 ,...,xm(m≤n) are given n-vectors andλ1 ,...,λmare given constants.Let X=(x1 ,...,xm) ,Λ=(λ1 ,λ2 ,...,λm) ,then the above inverse eigenvalue problemcan be written as followsProblem Given X∈Cn×m,Λ=(λ1 ,...,λm) ,find A∈S such thatAX =XΛ,where S is a given matrix set.We also discuss the so-called opti…     

时滞格微分方程组的行波解

本文利用Schauder不动点定理的方法和上、下解技巧,研究了时滞格微分方程组的行波解,给出了当系统的非线性项满足“拟单调条件”和“指数拟单调条件”时行波解的存在性.     

基于比率的三种群捕食者-食饵扩散系统的周期解

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Bernfeld-Haddock猜想的推广形式及其证明

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由主子阵和特殊次序缺损特征对构造Jacobi矩阵

In this paper,an inverse eigenvalue problem of constructing a Jacobian matrix from its prescribed specially ordered defective eigenpairs and a principal subma-trix is considered.The necessary and sufficient conditions for the existence and uniqueness of the solution are derived.Two numerical algorithms and two numer-ical examples are given.     

一个具有阶段结构的捕食者食饵系统的周期解

本文研究一类捕食者具有阶段结构的捕食者食饵系统,利用重合度理论建立了这类系统正周期解的存在性结果.     

THE SYMMETRIC AND SYMMETRIC POSITIVE SEMIDEFINITE SOLUTIONS OF LINEAR MATRIX EQUATION——B~TXB = D ON LINEAR MANIFOLDS

This paper discusses the solutions of the linear matrix equation B~T XB=D on some linear manifolds. Some necessary and sufficient conditions for the existence of the solution and the expression of the general solution are given. And also some optimal approximation solutions are discussed.     

Dirichlet外问题的概率数值方法

针对定解区域是无界区域的Dirichlet外问题,提出了一种新的有效的概率数值方法,它是从解的随机表达式出发,将无界区域上的问题转化成区域边界上的问题.此时,只要在边界上进行剖分,将问题离散化,然后在无界区域外的有界区域内构作一个辅助球,并且利用布朗运动、漂移布朗运动从球外一点出发,首中球面的位置和时间的分布等,就可以获得Dirichlet外问题的数值解.     

矩阵方程的M-对称解

定义了M-对称矩阵集GSRn×n(M),获得了矩阵方程ATXA=B存在M-对称解的充分必要条件．解集为非空时,得到了最小范数解和给定矩阵X*最佳逼近解．     

BOUNDARY VALUE PROBLEM FOR A GENERALIZED LINARD EQUATION

§ 1　 IntroductionThe existence of solution for boundary value problem( BVP) of the Liénard equationx" + f( x) x′+ g( x) =e( t) ,x( 0 ) =x( 2π) ,x′( 0 ) =x′( 2π) ( 1 )has been considered by a numberof authors[1～ 6] . In their papers,methods used are usuallyupper and lowers solutions methods,or topological degree methods. This paper applytopological degree method to investigate the existence ofsolution for boundary value prob-lem of a generalized Liénard equationa( t) x" + F( x,x′) …