广义正定矩阵与稳定矩阵的关系

本文首先修正了文[1]中有关广义正定矩阵与稳定矩阵关系的一系列错误,进而给出了广义正定矩阵与稳定矩阵的关系,最后,给出了广义正定矩阵的加性复合阵的有关性质.     

TOR方法的收敛性

匡蛟勋在[1]中提出了解大线性系统的双参数松驰法——TOR 方法,并讨论了系数矩阵为 Hermitian 正定及 L 矩阵时,TOR 方法的收敛性。曾文平 [2]中又讨论了系数矩阵是正定对称矩阵、H—矩阵、L—矩阵及弱对角占优不可约矩阵时,TOR 方法的收敛性。本文讨论系数矩阵是正定矩阵、广义正定矩阵、N—稳定矩阵时,TOR 方法的收敛性。拓广了文[1]、[2]的结果。     

实正定矩阵的复合矩阵的正定性

本文讨论了实正定矩阵的复合矩阵的正定性，并且给出了实正定矩阵的复合矩阵仍为正定矩阵的一个充要条件.     

正定复矩阵的若干性质

本文讨论一类正定复矩阵的某些性质，特别给出了两个正定复矩阵的积仍为正定的条件，以及正定复矩阵的一种分解．     

四元数矩阵方程AX=B的实部半正定解

一个n×n实四元数矩阵称为实部半正定(或正定)矩阵，如果对于任意的非零n维四元数列向量x，有Re[x·Ax]≥0(或>0)，本给出了四元数矩阵方程AX=B有实部半正定(或正定)矩阵解的充要条件及其通解的表达式，并给出了四元数分块阵为实部半正定(或正定)矩阵的一个判别法则。     

四元数矩阵方程AX=B的实部半正定解(英文)

一个ｎ×ｎ实四元数矩阵称为实部半正定（或正定）矩阵，如果对于任意的非零ｎ维四元数列向量ｘ，有Ｒｅ［ｘＡｘ］≥０（或＞０）．本文给出了四元数矩阵方程ＡＸ＝Ｂ有实部半正定（或正定）矩阵解的充要条件及其通解的表达式，并给出了四元数分块阵为实部半正定（或正定）矩阵的一个判别法则     

次亚正定矩阵的次Lōwner偏序

本文研究了次亚正定矩阵子阵的次Lōwner偏序，利用次Lōwner偏序，获得了几个用低阶矩阵的次亚正定性判别高阶矩阵次亚正定性的充要条件．     

非对称半正定矩阵的一些性质

非对称半正定矩阵的一些性质阳本傅（成都师范高等专科学校数学系６１１９３０）设Ａ是ｎ阶实矩阵（不一定对称），如果对任意实ｎ元向量Ｘ，均有Ｘ′ＡＸ０（＞０），就称Ａ为半正定矩阵（正定矩阵）．本文给出半正定矩阵的一种合同标准形，由此比较简捷地得出了半正定...     

关于正定矩阵的子式阵的正定性

研究正定矩阵的子矩阵,利用合同标准形分别给出了复正定矩阵的子式阵为复正定矩阵和实正定矩阵的子式阵为实正定矩阵的充分必要条件,其结果简单而实用.     

关于合成矩阵的正定性

利用标准形分别给出了复正定矩阵的合成矩阵为复正定矩阵和实正定矩阵的合成矩阵为实正定矩阵的充分必要条件,其结果简单而实用.     

关于广义正定矩阵的进一步推广

受到Johnson、佟文廷、夏长富的启发,进一步推广了广义正定矩阵的定义,并得出了更广义正定矩阵P∈PA+的若干性质.     

On a new simple method for evaluation of certain multiple definite integrals

This paper deals with a simple method of evaluation of certain multiple difinite integrals. This is followed by two main theorems concerning multiple difinite integrals. Some examples of applications are given.     

关于四元数体上自共轭矩阵的行列式和迹的几个定理

本文采用分析和代数的方法得到了四元数体上自共轭矩阵的行列式和迹的几个定理，推广和改进了文［３］，文［５］相类定理的结果。     

Finite dimensional spectral inverse problem for a bundle of hermitian quadratic forms

The paper is devoted to recovering the coefficients of a pair of Hermitian quadratic forms c(x, x) and (x, x) in a special basis, in which the matrix of the form c(x, x) is tridiagonal and the matrix of the form m(x, x) is diagonal. The form c(x, x) is positive definite, and the form m(x, x) is nondegenerate, but is not positive difinite in contrast with a well-known case. The data of the inverse problem include the spectrum λ₁...,λ_n of the bundle II_λ and the set of numbers ρ₁...,ρ_n connected with the main normalized elements of the bundle. A procedure for solving the inverse problem is described. The characteristic conditions for λ₁...,λ_n; are found that provide its solution. Bibliography: 5 titles. Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 186, pp. 33–36, 1990. Translated by T. N. Surkova.     

Complementarity forms of theorems of Lyapunov and Stein, and related results

The well-known Lyapunov's theorem in matrix theory / continuous dynamical systems asserts that a (complex) square matrix A is positive stable (i.e., all eigenvalues lie in the open right-half plane) if and only if there exists a positive definite matrix X such that AX+XA^* is positive definite. In this paper, we prove a complementarity form of this theorem: A is positive stable if and only if for any Hermitian matrix Q, there exists a positive semidefinite matrix X such that AX+XA^*+Q is positive semidefinite and X[AX+XA^*+Q]=0. By considering cone complementarity problems corresponding to linear transformations of the form I−S, we show that a (complex) matrix A has all eigenvalues in the open unit disk of the complex plane if and only if for every Hermitian matrix Q, there exists a positive semidefinite matrix X such that X−AXA^*+Q is positive semidefinite and X[X−AXA^*+Q]=0. By specializing Q (to −I), we deduce the well known Stein's theorem in discrete linear dynamical systems: A has all eigenvalues in the open unit disk if and only if there exists a positive definite matrix X such that X−AXA^* is positive definite.     

二次自伴矩阵多项式阵特征值界的数值计算

在参数不确定性线性系统的鲁棒控制研究中,常用到的一个指标就是使不确定性系统在输出反馈或状态反馈控制下的闭环系统在H∞-范数界γ的条件下的二次稳定.是否二次稳定,一般要验证能否找到一个正常数,ε使相应的R iccati方程有正定解.而R iccati方程一般情况下求解相当困难.本文通过具体的分析,提出了一种在给定正定矩阵的条件下,找使此正定阵是R iccati方程的解相对应的正常数ε的可能范围的方法,即求解二次自伴矩阵多项式阵特征值界的方法.文中详细给出了所用理论及算法.给出了求正常数ε范围的一个实例.     

Global dynamics of a special class of nonlinear semelparous Leslie matrix models

ABSTRACT

This paper considers the dynamics of nonlinear semelparous Leslie matrix models. First, a class of semelparous Leslie matrix models is shown to be dynamically consistent with a certain system of Kolmogorov difference equations with cyclic symmetry. Then, the global dynamics of a special class of the latter is fully determined. Combining together, we obtain a special class of semelparous Leslie matrix models which possesses generically either a globally asymptotically stable positive equilibrium or a globally asymptotically stable cycle. The result shows that the periodic behaviour observed in periodical insects can occur as a globally stable phenomenon.     

A faster,more stable method for computing the pth roots of positive definite matrices

An accelerated, more stable generalization of Newton's method for finding matrix pth roots is developed in a form suitable for finding the positive definite pth root of a positive definite matrix. Numerical examples are given and compared with the corresponding Newton iterates.     

THE STABILITY OF A KIND OF DISCRETE-TIME HOPFIELD NEURAL NETWORKS WITH ASYMPTOTICAL WEIGHTED MATRICES

In this paper, the authors analyze the stability of a kind of discrete-time Hopfield neural network with asymptotical weighted matrix, which can be expressed as the product of a positive definite diagonal matrix and a symmetric matrix. We obtain that it has asymptotically stable equilibriums if the network is updated asynchronously, and asymptotically stable equilibriums or vibrating final stage with 2 period if updated synchronously. To prove these, Lassale's invariance principle in difference equation is applied.     

The application of matrix theorems to the construction of stable difference representations of the equations of fluid dynamics

The paper applies matrix methods to formulate stable difference representations of the “difficult” pressure and continuity terms of the Navier-Stokes equations. The results are achieved by studying the eigenvalue properties of matrices that can be split into the sum of certain positive semi-definite and skew-symmetric matrices, and then using these properties to deduce stable difference representations of the Navier-Stokes equations.