关于弱交换PO—半群

在本文中我们引入弱交换ＰＯ－半群的概念，并研究这类半群到其Ａｒｃｈｉｍｅｄｅｓ子半群的半格分解，给出这类半群似于无序半群的相应结果的一个刻画。作为推论，我们得到弱交换ＰＯｅ－群和无序半群的相应刻画。     

关于弱交换PO—半群中的一个问题

本文引入弱交换ｐｏ－半群的概论２，研究这类半群到Ａｒｃｈｉｍｅｄｅａｎ子半群的半格分解，得到了这半群类似于具平凡序的弱交换半群的一个特征，由此在更一般的情形下回答了Ｋｅｈａｙｏｐｕｌｕ在「１」中提出的一个问题，并作为推论得到弱交换ｐｏｅ－半群和具平凡序的弱交换半群的已知结果。     

弱P—正则半群

在本文中,我们刻画弱P－正则半群上的最大幂等分离同余,并且证明了有超C－集的弱P－正则半群S[P]是拟P－正则当且仅当它同构于WB（p)[P^*]和某个弱正则^*-半群T的织积,其中B是S[P]的半带,最后,我们获得,在一般情况下,WB(p)[P]的弱P－正则半群但不是P－正则半群的条件。     

格值有限状态机的弱交换性

提出了格值有限状态机可弱交换的概念和格值变换半群可弱交换的概念,用矩阵和半群对格值有限状态机的弱交换性进行刻画,得出了格值有限状态机可弱交换的几个等价条件,并找出了格值有限状态机的弱交换性与其伴随第二类格值变换半群弱交换性的关系。此外,研究了格值有限状态机的满直积、限制直积、级联积、圈积及和的弱交换性,并研究了格值有限状态机伴随第二类格值随变换半群的全直积和限制直积的弱交换性,得出了其全直积和限制直积可弱交换的充分条件。     

弱交换富足序半群(Ⅰ)

本文将序半群上的 Ｇｒｅｅｎ’ｓ－关系推广为 Ｇｒｅｅｎ’ｓ＊一关系．给出主序（左、右）＊－理想、主序＊－滤特征描述和弱交换富足序半群的特征．用这些特征证明了一类弱交换富足序半群的结构定理：若序半群Ｓ满足 ,则Ｓ是弱交换富足序半群当且仅当Ｓ是左（右）单序半群｛（ｅ）（Ｓ）｝的半格．     

弱P-正则半群上的幂等元分离同余格

在本文中，弱P-正则半群上的弱P-正则，弱正规子集的概念被介绍．在弱P-正则半群上的弱P-正则，弱正规子集的若干性质被获得后，我们给出了弱P-正则半群上的幂等元分离同余格的一个刻画。     

非汉字符号~*-覆盖正则半群的构造(Ⅰ)

本文刻画了■*-覆盖正则半群的结构,得到了弱覆盖正则半群和覆盖正则半 群的分类.作为其主要结论的应用, 我们还得到了(？)-覆盖完全正则半群, 弱覆盖完 全正则半群和覆盖完全正则半群的结构刻画.     

非汉字符号~*-覆盖正则半群的构造(Ⅰ)

本文刻画了■*-覆盖正则半群的结构,得到了弱覆盖正则半群和覆盖正则半 群的分类.作为其主要结论的应用, 我们还得到了(？)-覆盖完全正则半群, 弱覆盖完 全正则半群和覆盖完全正则半群的结构刻画.     

2—弱幂P（Δ）—半群

本文刻划了半格不可分的２－弱幂ρ－半群，描述了半格可分的２－弱幂ρ－半群的结构，在此基础上，刻划了２－弱幂Δ－半群。     

2-弱幂P(△)-半群

本文刻划了半格不可分的＞－弱幂ｐ－半群，描述了半格可分的２－弱幂ｐ－半群的结构．在此基础上，刻划了２－弱幂△－半群．     

Nil-extensions of simple po-semigroups

In this paper, we generalize the concepts of (intra-, left, right, completely) π-regular semigroups without order to po-semigroups and discuss characterizations and relationships concerning them. Moreover, we introduce the concepts of nil-extensions of po-semigroups first, then consider properties and characterizations of po-semigroups which are nil-extensions of (left, rightt-) simple (π-regular) po-semigroups and complete semilattices of this class of po-semigroups.     

几类亚交换序半群

本文研究几类亚交换序半群的性质,并将具有单位元的亚交换序半群的一些结果扩张到这几类亚交换序半群上,使得这些结果更加细化,其中主要证明了以下定理：伪交换序半群可以分解成阿基米德序半群的半格．并且,一般来说,这种分解不是唯一的．     

Ordered semigroups whose elements are separated by prime ideals

In this paper we add one more characterization of intra-regular ordered semigroups in the existing bibliography by proving that the ordered semigroups whose elements are separated by prime ideals are actually the intra-regular ordered semigroups, a result which generalizes the corresponding result of semigroups (without order).     

On the Least Property of the Semilattice Congruences on PO-Semigroups

n on po-semigroups. We study the least property of (ordered) semilattice congruences, and prove: 1. N is the least ordered semilattice congruence on pr-semigroups (cf.[1]). 2. n is the least semilattice congruence on po-semigroups. 3. N is not the least semilattice congruence on po-semigroups in general. Thus, we give a complete solution to the problem posed by N. Kehayopulu in [1].     

Graphs and their associated inverse semigroups

Directed graphs have long been used to gain an understanding of the structure of semigroups, and recently the structure of directed graph semigroups has been investigated resulting in a characterization theorem and an analog of Frucht’s Theorem. We investigate two inverse semigroups defined over undirected graphs constructed from the notions of subgraph and vertex set induced subgraph. We characterize the structure of the semilattice of idempotents and lattice of ideals of these inverse semigroups. We prove a characterization theorem that states that every graph has a unique associated inverse semigroup up to isomorphism allowing for an algebraic restatement of the Edge Reconstruction Conjecture.     

纯整Ehresmann半群的若干刻划

本文介绍纯整Ehresmann半群．纯整Ehresmann半群是一类特殊的U-半富足半群，我们给出了这类半群的若干刻划，并讨论了一些特殊的纯整Ehresmann半群．     

Quasi-C-Ehresmann Semigroups and Their Subclasses

We introduce the concept of a quasi-C-Ehresmann semigroup. Some special quasi-C-Ehresmann semigroups will be considered. We will show that the quasi-C-Ehresmann semigroups are special U-semiabundant semigroups and orthodox U-liberal semigroups, which have been recently studied by several authors. Some characterization theorems of this new class of semigroups are obtained. Many results of quasi-C-semigroups in the literature can be extended to quasi-C-Ehresmann Semigroups.