非负矩阵Perron根界的估计式的改进

矩阵的谱半径在特征值估计理论、广义逆矩阵、数值分析以及矩阵序列、矩阵级数的收敛分析、控制理论中都有着极为重要的作用,近年来许多学者都致力于这方面的研究,提出了许多改进的谱半径估计方法,利用Perron补矩阵进行谱半径估计也一直受到广大学者的重视.通过研究矩阵的广义Perron补的性质,给出非负矩阵Perron根界的几个新的估计式。     

一类整系数多项式的不可约性与有理根存在性的判别

根据整系数多项式的系数所满足的条件,判定其分解式的唯一性和因式的不可约性,有理根的存在性,以及它们与给定多项式的不可约性的关系.     

Twisted Hamiltonian Lie algebras and their multiplicity-free representations

We construct a class of new Lie algebras by generalizing the one-variable Lie algebras generated by the quadratic conformal algebras (or corresponding Hamiltonian operators) associated with Poisson algebras and a quasi-derivation found by Xu. These algebras can be viewed as certain twists of Xu’s generalized Hamiltonian Lie algebras. The simplicity of these algebras is completely determined. Moreover, we construct a family of multiplicity-free representations of these Lie algebras and prove their irreducibility.     

Topological Duality for Boolean Algebras with a Normal <Emphasis Type="Italic">n</Emphasis>-ary Monotonic Operator

In this paper we shall give a topological duality for Boolean algebras endowed with an n-ary monotonic operator (BAMOs). The dual spaces of BAMOs are structures of the form , such that is a Boolean space, and R is a relation between X and a finite sequences of non-empty closed subsets of X. By means of this duality we shall characterize the equivalence relations of the dual space of a BAMO A that correspond biunivocally to subalgebras of A. We shall prove that there exist bijective correspondences between the lattice of congruences, the lattice of closed filters, and the lattice of certain closed subsets of the dual space of a BAMO. These correspondences are used to study the simple and the subdirectly irreducible algebras.      

整系数多项式在有理数域上不可约判别法

在艾森斯坦因判别法的基础上,证明了整系数多项式在有理数域上不可约的一个判定定理,再利用模p剩余类域知识对整系数多项式的系数进行了进一步的讨论,给出了一个整系数多项式在有理数域上不可约的新的判别法。     

On a mild generalization of the Schönemann irreducibility criterion

We state a mild generalization of the classical Schönemann irreducibility criterion in ?[x] and provide an elementary proof.     

Highest weight representations of a Lie algebra of Block type

For a field F of characteristic zero and an additive subgroup G of F, a Lie algebra B(G) of the Block type is defined with the basis {Lα,i, c|α∈G, -1≤i∈Z} and the relations [Lα,i,Lβ,j] = ((i 1)β- (j 1)α)Lα β,i j αδα,-βδi j,-2c,[c, Lα,i] = 0. Given a total order (?) on G compatible with its group structure, and anyα∈B(G)0*, a Verma B(G)-module M(A, (?)) is defined, and the irreducibility of M(A,(?)) is completely determined. Furthermore, it is proved that an irreducible highest weight B(Z )-module is quasifinite if and only if it is a proper quotient of a Verma module.     

一类具有预防接种和垂直传染的SIR传染病模型的定性分析

讨论了一类具有垂直传染和标准发生率的连续预防接种的SIR传染病模型,得到了基本再生数,并利用Lasalle不变集原理和Dulac定理讨论了地方病平衡点和无病平衡点的局部和全局稳定性。     

非奇异H矩阵的充分条件

从矩阵的元素出发,给出了非奇异H矩阵的新判据, 改进和推广了一些相关结果, 并用数值例子说明了结论的有效性.     

关于Ostrowski圆盘定理的一个注记

本文对Ostrowski给出的关于矩阵的特征值估计作一些讨论,特征值分布特性被揭示,进而得到了一个判定矩阵非奇异性的充分条件．