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。     

正则半群上的矩形群同余

文[1]中PetrichM定义了同余的核与迹，用它们描述了逆半群上的同余，Gomes在文[2]中定义了同余的核与超迹并描述了正则半群上的R-幂单(R-unipo-tent)同余，本文利用同余的核与超迹描述正则半群上的另一类重要同余，即矩形群同余．     

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。     

半群上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．研究了单幂幺半群上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．     

正则半群的左Clifford同余

本文给出了左 Clifford 半群的一个等价条件,研究了正则半群上的左 Clifford同余,用同余的核和同余的超迹描述了左 Clifford 同余,右 Clifford 同余和 Clifford 同余。     

D—正则半群上的同余

刻划Ｄ－正则半群上的如下同余：包括在Ｄ［Ｒ］中的最大同余、最大幂等元分离同余、（最小）基本强Ｄ－同余和群同余。     

关于Clifford半群上的fuzzy同余

利用半群fuzzy同余的概念,讨论一类特殊的完全正则半群,即Clifford半群上的fuzzy同余.研究该类半群上fuzzy同余的性质.在此基础上,给出Clifford半群上fuzzy同余的性质和特征,得到Cllifford半群上fuzzy同余为fuzzy消去同余的充要条件.     

Γ-半群的根同余-(3)

对于Ａ．Ｓｅｔｈ（１９８９）定义的正则Ｒｅｅｓ矩阵Γ－半群．本文讨论了其根同余，得出（（ａ）ｉμ，（ｂ））∈ＪΓ（μ０）当且仅当λ＝μ，且当且仅当λ与μ行相容，且ｉ与ｊ列相容．     

幺半群的强半格上的Rees矩阵半群的平移壳

设含幺元的半群A是幺半群A~_e的半格,其中A的幺元为1_A,A~_e的幺元为e,所有幺元e的集合为E(A),则对于幺半群A上的Rees矩阵半群S和幺半群A~_e上的Rees矩阵半群S~_e,以下五个条件是等价的:(1)任意的e∈E(A),a∈A,有ae=ea;(2)A是幺半群A~_e的强半格;(3)S是S~_e的强半格;(4)A的平移壳和A~_e的平移壳的强半格同构;(5)S的平移壳和S~_e的平移壳的强半格同构.     

Rees Matrix Covers and the Translational Hull of a Locally Inverse Semigroup

For any locally inverse semigroup S, there exists a maximal dense ideal extension of S within the class LI of all locally inverse semigroups (Pastijn and Oliveira, 2006 Pastijn , F. J. , Oliveira , L. ( 2006 ). Maximal dense ideal extensions of locally inverse semigroups . Semigroup Forum 72 : 441 – 458 . [Google Scholar], Preprint). Here we realize this maximal dense ideal extension in terms of a canonically constructed quotient of a regular Rees matrix semigroup over an inverse semigroup.     

Regular Semigroups Each of Whose Least Completely Simple Congruence Classes Has a Greatest Element

A regular semigroup S is termed locally F-regular, if each class of the least completely simple congruence ξ contains a greatest element with respect to the natural partial order. It is shown that each locally F-regular semigroup S admits an embedding into a semidirect product of a band by S/ξ. Further, if ξ satisfies the additional property that for each s ∈ S and each inverse (sξ)′ of sξ in S/ξ the set (sξ)′ ∩ V(s) is not empty, we represent S both as a Rees matrix semigroup over an F-regular semigroup as well as a certain subsemigroup of a restricted semidirect product of a band by S/ξ.     

The loop problem for Rees matrix semigroups

We study the relationship between the loop problem of a semigroup, and that of a Rees matrix construction (with or without zero) over the semigroup. This allows us to characterize exactly those completely zero-simple semigroups for which the loop problem is context-free. We also establish some results concerning loop problems for subsemigroups and Rees quotients.     

序半群的正则同余类

本文的目的是给出一个序半群的子集能成为某个正则同余的同余类的刻面,同时我们可以容易看出[5]中的关于一般半群(没有序关系)的相应的结论仅是本文的结论的应用.     

局部左正则纯正密群的一个等式

本文给出局部左正则纯正密群的一个等式.证明了一个完全正则半群是左半正规密群当且仅当它是局部左正则纯正密群.     

The Closed Subsemigroups of a Clifford Semigroup

In this paper we study the closed subsemigroups of a Clifford semigroup. shown that{∪- αεY＇ Gα, [ Y＇ ε P（Y）} is the set of all closed subsemigroups of It is a Clifford semigroup S = {Y; Gα; Фα,β}, where Y＇- denotes the suhsemilattice of Y generated by Y＇. In particular, G is the only dosed subsemigroup of itself for a group G and each one of subsemilattiees of a semilattiee is closed. Also, it is shown that the semiring P（S） is isomorphic to the semiring P（Y） for a Clifford semigroup S = [Y; Gα; Фα,β].     

The Closed Subsemigroups of a Clifford Semigroup

In this paper we study the closed subsemigroups of a Clifford semigroup. It is shown that {∪α∈Y′ Gα | Y′∈ P(Y) } is the set of all closed subsemigroups of a Clifford semigroup S = [Y; Gα; ?α, β], where Y′denotes the subsemilattice of Y generated by Y′. In particular, G is the only closed subsemigroup of itself for a group G and each one of subsemilattices of a semilattice is closed. Also, it is shown that the semiring P(S) is isomorphic to the semiring P(Y) for a Clifford semigroup S = [Y; Gα; ?α, β].