关于斜正定矩阵的一些性质

利用矩阵的次转置共轭和翻转矩阵等技巧,给出关于斜正定矩阵的一些性质,给出矩阵的斜对称部分与其逆之差是斜半正定的结论.     

线性互补问题中几类特殊矩阵与半正定矩阵之间的关系

线性互补问题中特殊矩阵M 的性质是线性互补问题中研究的重要部分之一,本文深入研究了Cf0矩阵与半正定矩阵、子正定矩阵与半正定矩阵之间的关系,并且得到了特殊矩阵是半正定矩阵的一些充分条件。     

关于构造单元刚度矩阵的“自由列式”方法

[1]中提出的单片检验IET(Individual Element Test)用于构造有限元的单元刚度矩阵.随后,此方法逐步改进,又有了构造单元刚度矩阵的“自由列式”方法.此公式将单元刚度矩阵对应常应变部分与高阶模态分别构造,没有交叉项,常应变部分是恒不变的.     

Toeplitz矩阵填充的四种流形逼近算法比较

 本文提出Toeplitz矩阵填充的四种流形逼近算法。在左奇异向量空间中对已知部分运用最小二乘法逼近,形成新的可行矩阵;并将对角线上的元素分别用均值,l₁范数,l_∞范数和中间数四种方法逼近使得迭代后的矩阵仍保持Toeplitz结构,节约了奇异向量空间的分解时间。最终找到合理的低秩矩阵来逼近未知的高秩矩阵,进而精确地完成Toeplitz矩阵的填充。理论上,分析了在一定条件下算法的收敛性。实验上,通过取不同的采样密度进行数值实验展示了四种算法的优劣。实验结果说明均值算法和l_∞范数算法大多用的时间较少,但是当采样密度和矩阵规模较大时,中间数算法的精度较高。     

三幂等矩阵的一些性质

重点探索了三幂等矩阵的性质.主要从矩阵乘积、线性变换和矩阵的秩等角度出发,将幂等矩阵的性质向三幂等矩阵推广,对三幂等矩阵的性质进行探究,得到了15个相关结论,并给出部分性质的详细推导过程.     

Hermite矩阵迹的几个不等式

本文研究了一类Hermite矩阵迹的不等式问题.利用J.R.Magnus在文献[4]中介绍的部分结果及其一些初等不等式,结合矩阵恒等变形的方法,得到了关于Hermite矩阵迹的一些与这些初等不等式平行的不等式.     

轻矩阵及其推广

在R.E.Hartwig工作的基础上进一步研究了轻矩阵,得到了轻矩阵的一些特性,且把轻矩阵推广到了广义轻矩阵,得到了广义轻矩阵的一个充要条件;部分回答了文[1]中R.E.Harwtig提出的一个公开问题：当A与B都为n除非负矩阵时,刻划方程AX=XB的非负解。     

一类亚半正定矩阵的左右逆特征值问题

1．引言在工程技术中常常遇到这样一类逆特征值问题：要求在一个矩阵集合S中，找具有给定的部分右特征对（特征值及相应的特征向量）和给定的部分左特征对（特征值及相应的特征向量）的矩阵．文［2］，［3］讨论了S为。x。实矩阵集合的情形．文［4］－［7］对S为nxn实对称矩阵．对称正定矩阵，对称半正定矩阵集合的情形进行了讨论．文【川讨论了S为亚正定阵集合的情形．并提到了对于亚半正定矩阵的情形目下无人涉及，有待进一步研究．本文将对S为nxn亚半正定矩阵集合的情形进行讨论．给出了亚半正定矩阵的左右逆特征值问题有解的充要条件…     

正定矩阵的性质及相关问题

正定矩阵具有非常广泛的应用.本文对正定矩阵的结论与重要性质进行了归纳总结,并在此基础上,对部分结论与性质进行了适当的推广.     

益智游戏“汉诺塔”中的矩阵运算

汉诺塔(Tower of Hanoi)问题源于印度一个古老传说,据此做成了益智游戏,蕴含大量的数学思想与方法.本文采用矩阵描述汉诺塔状态和圆盘移动过程,将圆盘从一个位置移动到另一个位置转化为矩阵的加法,进而构造由若干可能状态矩阵组成的图的邻接矩阵,计算其幂矩阵,由此很方便地求得完成汉诺塔游戏的所有可能的圆盘移动方案,求解过程简单,含义清晰,易于理解和实现.     

The Totally Non-positive Matrix Completion Problem

In this paper, the totally non-positive matrix is introduced. The totally non-positive completion asks which partial totally non-positive matrices have a completion to a totally non-positive matrix. This problem has. in general, a negative answer. Therefore, our question is for what kind of labeled graphs G each partial totally non-positive matrix whose associated graph is G has a totally non-positive completion? If G is not a monotonically labeled graph or monotonically labeled cycle, we give necessary and sufficient conditions that guarantee the existence of the desired completion.     

逆M矩阵模型的完备及其算法设计

1 引 言 M矩阵是具有非负对角元和非正非对角元且其逆是非负矩阵的一类矩阵.逆M矩阵即逆为M矩阵的一类非负矩阵.逆M矩阵在物理学,生物学,控制理论,神经网络方面有着重要的应用.所以对逆M矩阵的研究一直在持续不断的进行.一个“部分矩阵”是指在一个矩阵中,一些元素已经给定了,而另一些元素待定的矩阵.而一个矩阵的完     

TOEPLITZ AND POSITIVE SEMIDEFINITE COMPLETION PROBLEM FOR CYCLE GRAPH

We present a sufficient and necessary condition for a so-called Cnk pattern to have positive semidefinite (PSD) completion. Since the graph of the Cnk pattern is composed by some simple cycles, our results extend those given in [1] for a simple cycle. We also derive some results for a partial Toeplitz PSD matrix specifying the Cnk pattern to have PSD completion and Toeplitz PSD completion.     

一类缺项算子矩阵正补的谱刻画

对 于 具 有 离 散 谱 的 正 算 子 Ａ， Ｂ， 我 们 给 出 了 一 个 闭 集 成 为 ２ × ２ 缺 项 算 子 矩 阵 Ａ ？？ Ｂ 的某个正 补的谱的一些 判别条件     

缺项算子矩阵的幂等补

本文获得各类二阶缺项算子矩阵存在幂等补的充分必要条件,并且给出它们各自所有幂等补的参数表示形式．     

Idempotent completions of operator partial matrices

Necessary and sufficient conditions are obtained for operator partial 2 × 2 matrices to have an idempotent completion, and all such completions are parametrically represented. Project supported by National Natural Science Foundation of China and Provincial Natural Science Foundation of Shanxi     

Some Properties for the Euclidean Distance Matrix and Positive Semidefinite Matrix Completion Problems

The Euclidean distance matrix (EDM) completion problem and the positive semidefinite (PSD) matrix completion problem are considered in this paper. Approaches to determine the location of a point in a linear manifold are studied, which are based on a referential coordinate set and a distance vector whose components indicate the distances from the point to other points in the set. For a given referential coordinate set and a corresponding distance vector, sufficient and necessary conditions are presented for the existence of such a point that the distance vector can be realized. The location of the point (if it exists) given by the approaches in a linear manifold is independent of the coordinate system, and is only related to the referential coordinate set and the corresponding distance vector. An interesting phenomenon about the complexity of the EDM completion problem is described. Some properties about the uniqueness and the rigidity of the conformation for solutions to the EDM and PSD completion problems are presented.     

The completable digraphs for the totally nonnegative completion problem

In this paper, we study the totally nonnegative completion problem when the partial totally nonnegative matrix is non-combinatorially symmetric. In general, this type of partial matrix does not have a totally nonnegative completion. Here, we give necessary and sufficient conditions for completion of a partial totally nonnegative matrix to a totally nonnegative matrix in the cases where the digraph of the off-diagonal specified entries takes certain forms as path, cycles, alternate paths, block graphs, etc., distinguishing between the monotonically and non-monotonically labeled case.     

Related necessary conditions for completing partial latin squares

Three classes of necessary conditions for completing partial latin squares are studied. These condition classes are derived via network flow theory, bipartite graph matching theory and by relating the completion problem to triply stochastic matrices. The latter formulation suggest an integer programming model of the completion problem which is convenient for analyzing the relative strength of the three condition classes. It is shown that these classes are nested and examples are given to demonstrate that this nesting is proper.     

Solving Euclidean Distance Matrix Completion Problems Via Semidefinite Programming

Given a partial symmetric matrix A with only certain elements specified, the Euclidean distance matrix completion problem (EDMCP) is to find the unspecified elements of A that make A a Euclidean distance matrix (EDM). In this paper, we follow the successful approach in [20] and solve the EDMCP by generalizing the completion problem to allow for approximate completions. In particular, we introduce a primal-dual interior-point algorithm that solves an equivalent (quadratic objective function) semidefinite programming problem (SDP). Numerical results are included which illustrate the efficiency and robustness of our approach. Our randomly generated problems consistently resulted in low dimensional solutions when no completion existed.