可换幺半群的结构

关于“群”有各种各样的定义,本给出了有限幺半群成为群的一个条件。并对有限可换幺半群进行了讨论,通过对它的商集的研究,建立了有限可换幺半群与有限可换幺半群之间的关系,从而揭示了有限可换幺半群的结构。     

两类剩余幺半群

主要讨论了两类可换剩余幺半群的结构及其定定理，给出并证明了一些有关的等价条件和充分必要条件，然后证明了剩余运算满足消去律的充要条件。     

剩余幺半群的商结构

本文首先定义了交换剩余幺半群Ｍ相对于其子半群Ｐ（Ｍ）的商结构Ｍ／Ｐ（Ｍ），然后研究了它的性质并给出了一些同构定理。     

幺半群上的Rees矩阵半群的半格的结构

推广了Ｍ．Ｐｅｔｒｉｃｈ在文「１」中所用的方法，得到了幺半群上Ｒｅｅｓ矩阵半群的半格的一个结构定理，研究了单幂幺半群Ｒｅｅｓ矩阵半群的半格的性质并给出了矩形单幂幺半群的半格的若干等价刻划。     

项重写系统和自由幺半群

项重写系统起源于数理逻辑,是理论计算机科学的重要组成部分.关于项重写系统的一个主要问题是描述一个重写系统是否具有汇合或终止等基本性质.本文首先将一个项重写系统与自由幺半群上的二元关系联系起来.然后,基于自由幺半群上的项重写系统,刻画了收敛项重写系统与自由幺半群的商截面之间的关系.作为应用,分别给出了由三个元素生成的Platic幺半群和中国幺半群的截面.     

幺半群的内射类及投射类刻画

类比于一般环上模的内射类,定义了幺半群上的S-系的内射类和投射类,并利用它们刻画了几类特殊的幺半群．证明了完全内射幺半群和完全拟内射幺半群是等价的．并且证明了对于标致幺半群S,它是完全投射的当且仅当它是完全拟投射的当且仅当它上面的投射S-系构成了一个投射类．     

幺半群的半直积及其同余

给出了两个幺半群的半直积是Ｃｌｉｆｆｏｒｄ半群的充要条件及其结构。并讨论了逆半群半直积的Ｇｒｅｅｎ关系、最小群同余和极大幂等元分离同余。     

弱Hopf代数与正则幺半群

本文定义了弱Ｈｏｐｆ代数并研究了弱Ｈｏｐｆ代数的弱对极与类群元幺半群的关系．首先,本文给出弱Ｈｏｐｆ代数的一些基本性质;然后,对类群元幺半群是逆半群或纯正半群的某些弱Ｈｏｐｆ代数,描述了其弱对极的一些性质;最后,给出一类其类群元幺半群为正则半群的弱Ｈｏｐｆ代数．     

完全α—绝对纯幺半群

本文研究完全α－绝对纯幺半群，给出了这类半群的内部刻划定理。     

由n次幂等矩阵确定的交换幺半群

设R是含幺结合环,n≥2为自然数.对所有的k≥1,本文给出了n次幂等矩阵集Pk^n（R）={P｜P^n=P∈Mk（R）}上的一种等价关系,证明了P^n（R）=∪k=1^∞Pk^n（R）中的等价类在给定的加法运算下构成一个交换幺半群.     

Finite Commutative Chain Rings

A commutative ring with identity is called a chain ring if all its ideals form a chain under inclusion. A finite chain ring, roughly speaking, is an extension over a Galois ring of characteristic pⁿusing an Eisenstein polynomial of degree k. When p∤k, such rings were classified up to isomorphism by Clark and Liang. However, relatively little is known about finite chain rings when p∣k. In this paper, we allowed p∣k. When n=2 or when p∥k but (p−1)∤k, we classified all pure finite chain rings up to isomorphism. Under the assumption that (p−1)∤k, we also determined the structures of groups of units of all finite chain rings.     

The Extensional Structure of Commutative Noetherian Rings

Abstract

We show that finitely generated modules over a commutative Noetherian ring can be classified, up to isomorphism of submodule series, in a manner analogous to the classification of integers as products of prime numbers. In outline, two such modules have isomorphic submodule series if and only if 1) the set of minimal associated prime ideals of these modules coincide, 2) the multiplicities of these modules at these prime ideals coincide, and 3) the modules represent the same element in a certain group corresponding to the above set of prime ideals. Regarding condition 3), we show that, in the very special case that the ring is a Dedekind domain, the group corresponding to the prime ideal (0) is the ideal class group of the ring.     

On Normal Bases for Finite Commutative Rings

This paper is devoted to the introduction of extension rings S : = R[x]/gR[x] with a suitable polynomial g ? R[x] of arbitrary commutative rings R with identity and to the development of a normal basis concept of S over R, which is similar to that of Galois extensions of finite fields. We prove new results for Galois extensions of local rings and apply them together with the Chinese remainder theorem to solve the above task in a constructive way.     

有限交换群中的极大迷向子模

设有限群G作用在有限交换群E上,并且E带有一个G-不变的乘法辛型.如果U和V为E的两个极大迷向的G-子模,证明了相伴的两个辛G-模U⊥/U和V⊥/V同构.     

Finite Structurally Uniform Groups and Commutative Nilsemigroups

Ukrainian Mathematical Journal - Let S be a finite semigroup. By Sub(S) we denote the lattice of all its subsemigroups. If A ∈ Sub(S), then by h(A) we denote the height of a subsemigroup A in...     

On Polynomial Functions over Finite Commutative Rings

Let R be an arbitrary finite commutative local ring. In this paper, we obtain a necessary and sufficient condition for a function over R to be a polynomial function. Before this paper, necessary and sufficient conditions for a function to be a polynomial function over some special finite commutative local rings were obtained.     

Cut Vertices in Zero-Divisor Graphs of Finite Commutative Rings

A cut vertex of a connected graph is a vertex whose removal would result in a graph having two or more connected components. We examine the presence of cut vertices in zero-divisor graphs of finite commutative rings and provide a partial classification of the rings in which they appear.