Fuzzy Good Congruences on Left Semiperfect Abundant Semigroups

Motivated by studying fuzzy congruences in groups, semigroups, and ordered semigroups, and as a continuation of N. Kuroki and Y. Tan's works in regular semigroups in terms of fuzzy subsets, in this article we introduce the notions of a fuzzy good congruence relation, a fuzzy cancellative congruence relation on abundant semigroups, and give some properties, and characterizations of fuzzy good congruences on such semigroups. Furthermore, we characterize fuzzy good congruences of left semiperfect abundant semigroups, and get sufficient and necessary conditions for an abundant semigroup to be left semiperfect.     

亚纯正半群上的同余

本文讨论了亚纯正半群S上特殊同余间的关系.利用超迹和核给出了S上任一同余与特殊同余的关系及与群同余并的等式.用核正规系刻画了S上的极大幂等分离同余,得到了S/μ同构于E的几个等价条件.     

Congruences on *-Regular Semigroups

In this paper we study the congruences of *-regular semigroups, involution semigroups in which every element is p-related to a projection (an idempotent fixed by the involution). The class of *-regular semigroups was introduced by Drazin in 1979, as the involutorial counterpart of regular semigroups. In the standard approach to *-regular semigroup congruences, one ,starts with idempotents, i.e. with traces and kernels in the underlying regular semigroup, builds congruences of that semigroup, and filters those congruences which preserve the involution. Our approach, however, is more evenhanded with respect to the fundamental operations of *-regular semigroups. We show that idempotents can be replaced by projections when one passes from regular to *-regular semigroup congruences. Following the trace-kernel balanced view of Pastijn and Petrich, we prove that an appropriate equivalence on the set of projections (the *-trace) and the set of all elements equivalent to projections (the *-kernel) fully suffice to reconstruct an (involution-preserving) congruence of a *-regular semigroup. Also, we obtain some conclusions about the lattice of congruences of a *-regular semigroup. This revised version was published online in June 2006 with corrections to the Cover Date.     

富足半群上的F-好同余

引入了富足半群上F-好同余的概念,给出了富足半群上F-好同余的性质和特征.在此基础上,得到了富足半群上F-好同余的并为F-好同余的相关条件.最后,进一步对拟适当半群上的F-好同余作了讨论并得到了一些性质.     

正则半群上的广义逆半群同余

利用同余的核与超迹描述正则半群上的广义逆半群同余。     

半群的模糊同余扩张

本文引入半群的模糊同余扩张的概念,给出了模糊同余扩张的同态性质,同时,本文研究了带有模糊同余扩张性质的半群类,证明了一个半群S有模糊同余扩张性质当且仅当S有同余扩张性质,最后进一步给出 有模糊同余张张性质的半群类的特征。     

纯正半群上若干同余的刻划(英文)

本文在纯正半群上首先引入了关系ρｍｉｎ,ρｍａｘ,ρｍｉｎ和ρｍａｘ,刻划了纯正半群上一般同余的迹类。然后利用核－迹方法给出了纯正半群上几类特殊同余的等价刻划。在此基础上,进一步研究了各类同余间的相互联系,把逆半群上有关同余的若干结果推广到纯正半群上。     

完全零单半群的模糊同余

介绍完全零单半群上的真模糊同余和连接模糊三元组的概念,由此得到完全零单半群上的真模糊同余集和连接模糊三元组集之间的双射。     

半群的子半群上的同余扩张(英)

设ρ是个群S上的一个同余．如果S／ρ是矩形带,则称ρ是矩形带同余。本文刻画了半群上的最小矩形带同余．设T是半群S的子半群,本文给出了T上每个矩形带同余能扩张成S上矩形带同余的充分必要条件。     

Characterizations of Certain Congruences on Orthodox Semigroups

In this paper, we intrnduce the notation pmin,pmin p^min and p^min, by which we describe the trace classes and the kernel classes of general congruence p on orthodox semigronps.Then we have given and proved some equivalent characterizations of special congruences by mean of kernels and traces. On the basis of above-mentioned congruences, we further investigate theirrelations. Some results shout congruences on iverse semigroups are generalized to orthodox semigroups.     

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.     

序半群的一类正则同余

设S是有向序半群,本文给出了S上的一类正则同余,称为强序同余的定义及性质.证明了S的强序同余是强正则同余,但反之不成立.同时证明了强序同余格SOC(S)是S的同余格C(S)关于通常集合的交和传递积的V-完备的分配子格.     

序半群序同余的一个注记

序半群S的什么子集可以作为S的同余类是一个重要的问题. 在文[8]中,作者证明了如果序半群S的 理想$C$是$S$的某个同余类, 则$C$是凸的; 而且当$C$是强凸理想时，逆命题成立. 在本文中, 我们给出了序半群同余的一个新的构造，并证明了序半群$S$的理想$B$是$S$的某个同余类的充要条件是$B$是凸的.     

Permutative Semigroups Whose Congruences Form a Chain

Semigroups whose congruences form a chain are often termed -semigroups. The commutative -semigroups were determined by Schein and by Tamura. A natural generalization of commutativity is permutativity: a semigroup is permutative if it satisfies a non-identity permutational identity. We completely determine the permutative -semigroups. It turns out that there are only six noncommutative examples, each of which has at most three elements.     

Finite Derivation Type for Semigroups and Congruences

We consider a congruence ρ on a semigroup S as a subsemigroup of the direct product S × S. We prove that if ρ has finite derivation type (FDT), then so does S.