Hadamard matrices of Williamson type: A challenge for Computer Algebra

We describe new families of challenging polynomial systems of equations arising in the construction of Hadamard matrices of Williamson type. These systems depend on a parameter and exhibit a number of symmetries. We demonstrate that Genetic Algorithms form a suitable tool to apply to these systems, for which the traditional Computer Algebra methods seem to be inappropriate.     

Semi-tensor product of matrices and its application to Morgen's problem

This paper proposes a new matrix product, namely, semi-tensor product. It is a general-ization of the conventional matrix product. Meanwhile, it is also closely related to Kronecker (tensor) product of matrices. The purpose of introducing this product is twofold: (i) treat multi-dimensional da-ta; (ii) treat nonlinear problems in a linear way. Then the computer and numerical methods can be easily used for solving nonlinear problems. Properties and formulas are deduced. As an application, the Morgan's problem for control systems is formulated as a numerically solvable problem.     

公理化的矩阵半张量积

本文给出矩阵半张量积的一个公理化框架, 它包括矩阵–矩阵半张量积、矩阵–向量半张量积和向量–向量半张量积. 首先, 对目前通用的各类矩阵半张量积的基本性质与应用做一个综述性的回顾. 然后, 介绍一种新近出现的矩阵半张量积, 即保维数矩阵半张量积. 跟普通矩阵乘法一样, 它是多功能的, 即它可同时实现矩阵–矩阵乘积、矩阵–向量乘积和向量–向量乘积这3种功能. 最后, 本文介绍保维数矩阵半张量积的一些代数性质, 包括非方矩阵的Cayley-Hamilton定理, 非方矩阵的特征值、特征向量等.     

Methods of computing weighted pseudoinverse matrices with singular weights

Three iterative processes are constructed and investigated for computing weighted pseudoinverse matrices with singular weights and ML-weighted pseudoinverse matrices. Two of them are based on the decompositions of the weighted pseudoinverse matrix with singular weights into matrix power series, and the third is a generalization of the Schulz method to nonsingular square matrices. Translated from Kibernetika i Sistemnyi Analiz, No. 5, pp. 150–169, September–October, 1999.     

A recursive partitioning algorithm for inverting tridiagonal matrices

Motivated by the recursive partitioning algorithm of Evans [2], we present a new algorithm for inverting tridiagonal matrices. Our derivation of the algorithm is different but elementary. The present algorithm has potential for its vector and parallel implementation.     

关于交换半环上一类矩阵的研究

对半环上可逆矩阵的概念进行推广,给出了[e]-可逆矩阵的定义。通过探讨可逆矩阵与[e]-可逆矩阵之间的内在联系,给出了交换半环上[e]-可逆矩阵的等价刻画。同时,对交换半环上[e]-可逆矩阵的全体关于矩阵乘法构成的半群进行研究,给出了此类矩阵半群的分解定理,并证明了此类矩阵半群均存在极大子群,且所有极大子群的并是Clifford半群。     

Least-squares problem for the quaternion matrix equation AXB+CYD=E over different constrained matrices

For any A=A ₁+A ₂ j∈Q ^n×n and η∈<texlscub>i, j, k</texlscub>, denote A ^{η H} =?η A ^H η. If A ^{η H} =A, A is called an $\eta$-Hermitian matrix. If A ^{η H} =?A, A is called an η-anti-Hermitian matrix. Denote η-Hermitian matrices and η-anti-Hermitian matrices by η HQ ^n×n and η AQ ^n×n , respectively.

By using the complex representation of quaternion matrices, the Moore–Penrose generalized inverse and the Kronecker product of matrices, we derive the expressions of the least-squares solution with the least norm for the quaternion matrix equation AXB+CYD=E over X∈η HQ ^n×n and Y∈η AQ ^n×n .     

Language acceptability of finite automata based on theory of semi‐tensor product of matrices

Using the theories of many‐valued logic and semi‐tensor product of matrices (STP), this paper investigates how to mathematically determine whether or not a regular language is recognized by finite automata (FA). To this end, the dynamic behaviour of FA is first formulated as bilinear dynamic equations, which provides a uniform model for deterministic and non‐deterministic FA. Based on the bilinear model, the recognition power of FA understanding of regular languages is investigated and several algebraic criteria are obtained. With the algebraic criteria, to judge whether a regular sentence is accepted by a FA or not, one only needs to calculate an STP of some vectors, rather than making the sentence run over the machine as traditional manners. Further, the inverse problem of recognition is considered, an algorithm is developed that can mathematically construct all the accepted sentences for a given FA. The algebraic approach of this paper may be a new angle and means to understand and analyse the dynamics of FA.     

A unified presentation of some classes of meromorphically multivalent functions

The authors introduce and investigate various properties of a general class

U_k[p,a,β,A,B]

p, k ε N {1, 2, 3,…,}; 0 α < p; β 0

;

−1 A < B 1; 0 < B 1)

,which unifies and extends several (known or new) subclasses of meromorphically multivalent functions. The properties and characteristics of this general class, which are presented here, include growth and distortion theorems; they also involve Hadamard products (or convolution) of functions belonging to the class U_k[p,α,β,A,B].     

基于矩阵半张量积的有限值动态系统的最新进展

布尔网络可以简洁有效地描述作用在有限集上的动态离散模型.然而,随着研究的深入以及一些实际问题的需要,传统的布尔网络已经不能满足建模的需求,由此衍生出多值逻辑网络以及混合值逻辑网络,统称为有限值动态系统.通过矩阵半张量积,有限值动态系统可以转化为便于处理的等价代数形式.鉴于此,对矩阵半张量积以及有限值动态系统的最新发展进...     

有限博弈的矩阵半张量积方法

矩阵半张量积被广泛地应用在有限博弈的研究中,例如:1)演化博弈; 2)势博弈; 3)有限博弈的向量空间分解; 4)基于势博弈的优化与控制; 5)合作博弈等.本文的目的,就是对上述各种应用做一个全面的介绍,包括其原理、主要成果、以及尚待解决的问题.     

多尺度积的协方差矩阵行列式的角点检测方法

研究平面轮廓局部支撑域上的协方差矩阵,通过对图像协方差矩阵的特征值和特征向量的分析,以V角点模型为例,证明了协方差矩阵行列式在角点位置有唯一的极值响应.同时,为了有效地融合各个尺度信息,采用多尺度乘积方法来增强角点响应的幅度,抑制非角点或噪声的幅度.基于此,提出以多尺度乘积的协方差矩阵行列式作为角点响应函数的角点检测算...     

Matrix approach to simplification of finite state machines using semi‐tensor product of matrices

In this paper, we use a new mathematical tool, semi‐tensor product of matrices, to investigate the problem of simplification of finite state machines (FSMs) in a mathematical manner. First, based on the dynamic equations of state transition and output behavior which are developed recently, an algebraic criterion of k‐difference states is established. Second, using the criterion, a scheme is designed to construct the incompatible graphs of FSMs. Third, with the incompatible graphs and the method of searching internally stable sets of graphs proposed by the authors, a solution is proposed to obtain all of the compatible state set (CSS) of FSMs. Then, with the aid of the CSS, we investigate three kinds of structures of state space of FSMs, including compatible cover of state set (CCSS), representative set of state set (RSSS), and minimum representative set of state set (MRSSS); necessary and sufficient conditions are proposed to formulate the three kinds of structures. Finally, examples are given to exemplify minimum realizations of FSMs by these conditions.     

区间矩阵二次稳定的充分必要条件

提出了区间矩阵二次稳定的充分必要条件,以及相应的稳定裕度的计算方法.结论以线性矩阵不等式(LMI)的形式给出.利用功能强大的LMI工具,求解非常方便.所给实例表明,该方法用于确定区间矩阵的鲁棒稳定性及其稳定裕度,非常有效.     

Stability analysis of a general family of nonlinear positive discrete time-delay systems

In this paper, we propose a new approach to analyse the stability of a general family of nonlinear positive discrete time-delay systems. First, we introduce a new class of nonlinear positive discrete time-delay systems, which generalises some existing discrete time-delay systems. Second, through a new technique that relies on the comparison and mathematical induction method, we establish explicit criteria for stability and instability of the systems. Three numerical examples are given to illustrate the feasibility of the obtained results.     

Series expansion of weighted pseudoinverse matrices and iterative methods for calculating weighted pseudoinverse matrices and weighted normal pseudosolutions

Weighted pseudoinverse matrices are expanded into matrix power series with negative exponents and arbitrary positive parameters. Based on this expansion, iterative methods for evaluating weighted pseudoinverse matrices and weighted normal pseudosolutions are designed and analyzed. The iterative methods for weighted normal pseudosolutions are extended to solving constrained least-squares problems. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 1, pp. 32–62, January–February 2006.     

基于矩阵方法的Banzhaf值的计算及应用

在合作博弈中, Banzhaf值提供了每个参与者形成大联盟的预期边际贡献,因此Banzhaf值的求解是一个重要的研究内容.本文首先回顾合作博弈及Banzhaf值的定义,并且运用矩阵半张量积,给出合作博弈特征函数的代数表示.然后给出了Banzhaf值的等价的代数形式和简捷的计算方法.最后将所得结果应用于生物网络中,用Banzhaf值度量遗传疾病基因相关性的可能性,确定与遗传疾病发病高度相关的基因.     

A test for the equality of covariance matrices when the dimension is large relative to the sample sizes

A simple statistic is proposed for testing the equality of the covariance matrices of several multivariate normal populations. The asymptotic null distribution of this statistic, as both the sample sizes and the number of variables go to infinity, is shown to be normal. Consequently, this test can be used when the number of variables is not small relative to the sample sizes and, in particular, even when the number of variables exceeds the sample sizes. The finite sample size performance of the normal approximation for this method is evaluated in a simulation study.     

An assessment of a new technique for the representation of boolean matrices

A general-purpose method, based on a sparse matrix approach, is proposed for the representation of boolean matrices, and algorithms are presented both for representation formation and element access. The method is then compared with the bit-map approach using the criteria of storage requirements, element access time, and execution time for logical operations on the whole matrix. Finally the conditions are discussed under which the proposed method may be profitably used in preference to the bit-map approach.     

Testing equality of covariance matrices when data are incomplete

In the statistics literature, a number of procedures have been proposed for testing equality of several groups’ covariance matrices when data are complete, but this problem has not been considered for incomplete data in a general setting. This paper proposes statistical tests for equality of covariance matrices when data are missing. A Wald test (denoted by T₁), a likelihood ratio test (LRT) (denoted by R), based on the assumption of normal populations are developed. It is well-known that for the complete data case the classic LRT and the Wald test constructed under the normality assumption perform poorly in instances when data are not from multivariate normal distributions. As expected, this is also the case for the incomplete data case and therefore has led us to construct a robust Wald test (denoted by T₂) that performs well for both normal and non-normal data. A re-scaled LRT (denoted by R^*) is also proposed. A simulation study is carried out to assess the performance of T₁, T₂, R, and R^* in terms of closeness of their observed significance level to the nominal significance level as well as the power of these tests. It is found that T₂ performs very well for both normal and non-normal data in both small and large samples. In addition to its usual applications, we have discussed the application of the proposed tests in testing whether a set of data are missing completely at random (MCAR).