Generalized Inverses of Matrices over Rings

Let R be a ring, * be an involutory function of the set of all finite matrices over R. In this paper, necessary and sufficient conditions are given for a matrix to have a (1,3)-inverse, (1,4)-inverse, or Moore-P enrose inverse, relative to *. Some results about generalized inverses of matrices over division rings are generalized and improved.     

Approximation Theorems of Moore-Penrose Inverse by Outer Inverses

1 Introduction and preliminaries Let X and Y be two Hilbert spaces and T a bounded linear operator from X into Y . We use D(T ), N(T ) and R(T ), respectively, to denote the domain, null space and range of T . Recall that a linear operator T # : Y → X is…     

广义B—D逆及其应用

本文首先给出了著名的Bott-Duffrin逆(简称B-D逆)A_(L)~((-1))的许多进一步的性质与新的应用,指出了A_(L)~((-1))的存在性与方程组的解的两种唯一性之间的紧密联系;然后定义了广义B-D逆A_(L)~(+)=P_L(AP_L+P_L~⊥)~+,讨论了A_(L)~(+)的一些性质,给出了当A为一般方阵与当A为L=N(B)—非负定阵时关于方程组(1)的可解性的方便的判别条件以及有解时其解的显式,统一处理了在最优化、线性统计推断、二维插值中出现的方程组(1)与约束二次极值问题的求解问题。     

Algorithms for Finding the Inverses of Factor Block Circulant Matrices

In this paper,algorithms for finding the inverse of a factor block circulant matrix, a factor block retrocirculant matrix and partitioned matrix with factor block circulant blocks over the complex field are presented respectively.In addition,two algorithms for the inverse of a factor block circulant matrix over the quaternion division algebra are proposed.     

具有E—逆断面的正则半群的结构定理

讨论了具有E－逆断面的正则半群的性质;并给出了具有E－逆断面的正则半群的一种结构定理。     

关于BZ—代数中的群逆理想

证明了如下结果：如果Ａ是ＢＺ－代数Ｘ的一个理想，则Ｚ（Ａ）必是Ｘ的一个群逆理想，这里ＡＺ（Ａ）＝｛ｘ∈Ｘ｜０＊（０＊ｘ）∈Ａ｝．     

On a Comparison Property of M—matrices

IntheresearchonthetheoryofM-matrices,wefrequentlyneedthefollowingtheoremasatool,whichiscalledthecomparisontheoremofanonsingularM-matrix(forexamplesee[5,Theorem2.2.5j).TheoremALetAbeanonsingularM-matrix,andletBbeaZ-matrixwithB2A.Then(1)BisanonsingularM-matrixI'(2)detB2detAj(3)A-'2B-'.obviously,theabovetheoremisnottrueforAtobeasingularM-matrix.InthispaperweshallextendTheoremAtOanyM-matrix,herethegeneralizedinverseisconsideredforgeneralizingassertion(3)ofTheoremA.AllnOtationanddefiniti…     

一类分块矩阵的Moore—Penrose逆及其应用

设M=为复数域上一个分块矩阵.其中A.B,C.D分别为m×n,m×k,l×n,l×k矩阵.在本文中我们给出了分块矩阵M在满足秩可加性条件     

Moore-Penrose Inverses and Group Inverses of Block k-Circulant Matrices

Ｍｏｏｒｅ－Ｐｅｎｒｏｓｅ　Ｉｎｖｅｒｓｅｓ　ａｎｄ　Ｇｒｏｕｐ　Ｉｎｖｅｒｓｅｓ　ｏｆ　Ｂｌｏｃｋ　ｋ－Ｃｉｒｃｕｌａｎｔ　ＭａｔｒｉｃｅｓＭｏｏｒｅ－ＰｅｎｒｏｓｅＩｎｖｅｒｓｅｓａｎｄＧｒｏｕｐＩｎｖｅｒｓｅｓｏｆＢｌｏｃｋｋ－Ｃｉｒｃｕｌａｎ...     

用于积分方程解的广义逆函数值Pade逼近的ε—算法和η—算法

为加速具有函数值系数的幂级数收敛并估计积分方程的特征值，建立了两个计算广义逆函数值Pade逼近的有效的递推算法：ε－算法和η－算法，借助于这两个算法之间的内在关系，给出了广义函数值Pade逼近的名的Wynn恒等式。     

态射的广义Moore—Penrose逆

本文定义了态射的广义Ｍｏｏｒｅ－Ｐｅｎｒｏｓｅ逆，给出了它存在的一些充要条件，确定了它的一些表达式，推广了关于态射的Ｍｏｏｒｅ－Ｐｅｎｒｏｓｅ逆的相应结果。     

L—逆左系对幺半群的刻画

正则左Ｓ－系是ｖｏｎ ｎｅｕｍａｎｎ正则半群的自然推广，逆左Ｓ－系是逆半群的自然扩广，作为左逆半群的自然推广，本文引入了Ｌ－逆左系的概念，并用来刻画了几类幺半群，如左逆幺半群，逆幺半群，ａｄｅｑｕａｔｅ幺半群等。     

矩阵之和的加权Moore—Penrose逆

§1.引言 Cline在[2]中讨论了矩阵UU~* VV~*的广义逆,并当UV~*=0(或U~*V=0)时给出了矩阵之和U V的广义逆的表达式。本文讨论矩阵UW_1U~* VW_2V~* VT~*U~* UTV~*的加权广义逆,其中[_(T~*W_2)~(W_1T)]是正定矩阵。并当UN~(-1)V~*=0(或U~*MV=0)时给出了矩阵之和U V的加权广义逆的表示。作为特例,给出了不同于[2]的UU~* VV~*及U V的广义逆的表达式。     

On the Characterization of a Class of π—inverse Semigroups

51.PreliminatriesS.Bogdanovicgaveacharacterizationforstronglyrr-inversesemigroupsinLlJ.TheclassofrightinversesemigroupsisinvestigatedbyP.S-Venkatesanin[2j.Inthispaper,thenotionofstronglyrightff-inversesemigroupsisintroduced.Characteri-zationofthisclassofsemigroupsobtained-Definition1.1[1jAff-regularsemigroupsissaidtobeK-orthodoxifE,,thesetofidem-potentsinS,isasubsemigroupofS.Definition1.2[1jAK-regularsemigroupsiscalledstronglyK-inverseifef=feforev-erye,feE,.Definition1.3Aff-regularsemi…