Rank Reducing Matrix Norms

We consider approximation numbers for some norms on matrices, and look at the question when a closest rank h p approximant can be chosen to reduce the rank of a matrix by p . If the latter is always possible, we call the norm rank p reducing. It is easily seen that any unitarily invariant norm is rank p reducing. We show that any absolute norm on $\shadC^{n \times m}$ is rank n m 1 reducing and that the numerical radius norm on $ \shadC^{n\times n}$ is rank n m 1 reducing as well. Non-examples and computations of approximation numbers are also presented.     

L-矩阵与三角模

利用完备的分配格L上三角模定义L上的矩阵运算,给出这些运算的一些基本性质,并且详细讨论L上的几类方阵.     

一类二元函数连续性的等价刻画及在三角模上的应用

关于二元函数的连续,经典数学分析中有熟知的结果,即"如果二元函数连续,则必关于每个单变量连续。反之,则未必"。本文证明对于单调且对称的二元函数而言,其二元连续等价于单变量连续,并重新定义了三角模的连续。     

三角模糊数互补判断矩阵的一种排序方法

给出三角模糊数互补判断矩阵的概念及三角模糊数相互比较的可能度公式 ,提出一种基于可能度的三角模糊数互补判断矩阵排序方法 ,通过算例说明该方法的可行性和有效性。     

Modular Automorphisms of Upper Triangular Matrices over a Commutative Ring Preserving Rank One

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Equivalent Representations of Complex Positive Definite Matrices

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稳定秩1环上三个三角矩阵的积

证明了环R为稳定秩 1环当且仅当R上的每个 2× 2可逆矩阵均可以表成乘积1　 0x　 11　y0　 1u　 0z　v ,其中x ,y ,z∈R ,u ,v∈GL1(R) ;这证明了 [1]中定理 1的逆命题也成立 ;并把 [2 ]中的主要结果推广到了非交换环上 .     

三角模糊数判断矩阵理论及排序方法研究

由于三角模糊数运算的复杂性和特殊性,许多经典判断矩阵的理论并非完全适用于三角模糊数判断矩阵.首先指出目前文献中三角模糊数判断矩阵排序向量研究中存在的问题,并对经典判断矩阵的理论和性质在三角模糊数中是否完全适用进行了证明,然后基于已经证明在三角模糊数判断矩阵所适用的性质,分别建立了最小二乘法的三角模糊数互反互补判断矩阵目标优化模型,通过求解其模型可得到矩阵的权重向量,最后利用已有的三角模糊数排序公式求得决策结果.算例分析验证了该方法的正确性和有效性.     

The Distance to Upper Triangular Operator Spaces of Von Neumann Algebras

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Identities of the Semigroup of Upper Triangular Tropical Matrices

A new family of identities satisfied by the semigroups U _n (𝕋) of n × n upper triangular tropical matrices is constructed and an elementary proof is given.     

由 n×n 上三角Toeplitz矩阵所构成的 超循环矩阵族

在Feldman和Costakis所做的结果的基础上,进一步考虑了超循环算子族的一些问题,设Τ=(T_1,…,T_m)是一组由m个上三角Toeplitz复矩阵构成的矩阵组,给出了一个Τ是超循环的充分必要条件.     

On Strongly Clean Matrix and Triangular Matrix Rings

A ring R with identity is called “clean” if every element of R is the sum of an idempotent and a unit, and R is called “strongly clean” if every element of R is the sum of an idempotent and a unit that commute. Strongly clean rings are “additive analogs” of strongly regular rings, where a ring R is strongly regular if every element of R is the product of an idempotent and a unit that commute. Strongly clean rings were introduced in Nicholson (1999 Nicholson , W. K. (1999). Strongly clean rings and Fitting's lemma. Comm. Algebra 27:3583–3592. [CSA] [Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) where their connection with strongly π-regular rings and hence to Fitting's Lemma were discussed. Local rings and strongly π-regular rings are all strongly clean. In this article, we identify new families of strongly clean rings through matrix rings and triangular matrix rings. For instance, it is proven that the 2 × 2 matrix ring over the ring of p-adic integers and the triangular matrix ring over a commutative semiperfect ring are all strongly clean.     

基于专家重要性的语言诱导有序加权平均算子的多粒度语言组合判断矩阵的相容性和一致性

定义了多粒度语言判断矩阵的基于专家重要性的语言诱导有序加权平均(I-LIOWA)算子的概念,利用I-LIOWA算子集结基于不同粒度语言判断矩阵而得到组合语言判断矩阵,并且研究了组合语言判断矩阵、其导出矩阵和特征矩阵的之间相容性和一致性的一些性质,为群决策中使用语言偏好信息提供了理论依据。     

Norm Attainability of Elementary Operators and Derivations

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关于布尔矩阵半群和非负矩阵半群的几点注记

本文重点讨论了布尔矩阵半群中的幂等、广义幂等、素矩阵以及它们之间的联系，对非负矩阵半群上的类零型结构也进行了研究．     

四元数矩阵的右特征值的虚部的估计

指出四元数矩阵A的右特征的虚部的模值是唯一确定的，得到了一些关于A的右特征值的虚部模的估计，推广改进了屠伯埙教授的相应结果．     

非线性算子的若干性质及一类积分方程的正解

文中给出了非线性算子的若干性质，并利用其讨论了一类积分方程正解的存在唯一性。     

Triangular finite elements of HCT type and classC ρ

Let τ be some triangulation of a planar polygonal domain Ω. Given a smooth functionu, we construct piecewise polynomial functionsv∈C ^ρ(Ω) of degreen=3 ρ for ρ odd, andn=3ρ+1 for ρ even on a subtriangulation τ₃ of τ. The latter is obtained by subdividing eachT∈ρ into three triangles, andv/T is a composite triangular finite element, generalizing the classicalC ¹ cubic Hsieh-Clough-Tocher (HCT) triangular scheme. The functionv interpolates the derivatives ofu up to order ρ at the vertices of τ. Polynomial degrees obtained in this way are minimal in the family of interpolation schemes based on finite elements of this type.     

形式三角矩阵的PP和半遗传环(英文)

In this paper the sufficient and necessary conditions are given for a formal triangular matrix ring to be right PP, generalized right PP, or semihereditary, respectively.