共查询到20条相似文献,搜索用时 31 毫秒
1.
众所周知,Clifford半群是正则半群类中的一类重要半群,本文定义正规 Ehresmann型wrpp半群,它是Clifford半群在wrpp半群类中的推广,给出了此类半群的若干刻划. 相似文献
2.
In this paper, we introduce an important subclass of quasiregular semigroups, namely the class of C*-quasiregular semigroups. This class of semigroups contains the classes of Clifford semigroups, quasi Clifford semigroups, C-quasiregular semigroups and their generalizations as its subclasses. Some characterization theorems for such semigroups are obtained. The structure of this kind of quasiregular semigroups is investigated by using the generalized ?-product of some semigroups on a semilattice Y. Construction techniques of such classes of semigroups are particularly demonstrated. 相似文献
3.
Given the importance of Morita theory of semigroups, we continue the study on the local structure of semigroups. Here we consider a class of nonregular semigroups, called locally U-commutative semigroups having U-local units, containing the classes of locally inverse semigroups, locally adequate semigroups, locally Ehresmann semigroups, and semigroups with local units having locally commuting idempotents. Our aim is to give a Rees matrix covering theorem for such semigroups with a partial McAlister sandwich bundle, and hence to put all the existing results into one context. 相似文献
4.
V. A. Molchanov 《Semigroup Forum》1983,27(1):155-199
At present, there are quite a few investigations in the theory of semigroups devoted to semigroups of mappings on graphs. Up to now, endomorphism semigroups of graphs, extensive transformation semigroups of graphs, coloring semigroups of graphs and other semigroups of special mappings on graphs have been studied. The results obtained show the way graphs are determined by the above-mentioned semigroups. They also show the structure of semigroups of mappings and interrelations between properties of graphs and corresponding properties of semigroups associated with the graphs. This paper gives a survey of the main results in this field. 相似文献
5.
We study a class of special strongly rpp semigroups, namely, the class of super rpp semigroups. These super rpp semigroups
are generalizations of both superabundant semigroups and Clifford semigroups within the class of rpp semigroups. In particular,
we prove that a super rpp semigroup is a semilattice of D
(l)-simple strongly rpp semigroups. Our result not only generalizes a well-known theorem of Clifford in the class of completely
regular semigroups but also strengthens some structure theorems obtained by Ren-Shum for superabundant semigroups which are
orthodox. Some special super rpp semigroups are considered and discussed. 相似文献
6.
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. 相似文献
7.
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. 相似文献
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10.
In this paper we investigate the structure of semigroups with the ideal retraction property i.e., semigroups which are not simple and have the property that each ideal is a homomorphic retract of the semigroup. We present examples to show that the ideal retraction property is neither hereditary nor productive. That this property is preserved by homomorphisms is established for some classes of semigroups, but the general question remains open. The classes of semigroups investigated in this paper are separative semigroups, ideal semigroups, semilattices, cyclic semigroups, nil semigroups, and Clifford semigroups. It is established that a semigroup with zero 0 which is expressible as a direct sum of each ideal and a dual ideal (complement with 0 adjoined) has the ideal retraction property. The converse holds for ideal semigroups, and an example is presented which demonstrates that the converse does not hold in general. 相似文献
11.
Recently, Billhardt has characterized the locally
inverse semigroups embeddable in Rees matrix semigroups
over generalized inverse semigroups. We prove here that
these semigroups are just the locally inverse semigroups
having weakly E-unitary covers. 相似文献
12.
本文引入了--格林关系和--富足半群,研究了满足同余条件含有中间幂等元的--富足半群.利用具有中间幂等元的由幂等元生成的正则半群和◇-拟恰当半群建立了满足同余条件含有中间幂等元的◇-富足半群的结构. 相似文献
13.
Patricio Jara 《Journal of Mathematical Analysis and Applications》2008,344(2):956-968
This paper extends the Hille-Phillips functional calculus and rational approximations results due to R. Hersh, T. Kato, P. Brenner, and V. Thomée to generators of bi-continuous semigroups. The method yields error estimates for rational time-discretization schemes for such semigroups, in particular for dual semigroups, Feller semigroups such as the Ornstein-Uhlenbeck semigroup, the heat semigroup, semigroups induced by nonlinear flows, implemented semigroups, and evolution semigroups. Furthermore, the results provide error estimates for a new class of inversion formulas for the Laplace transform. 相似文献
14.
双参数半群理论是研究Markov过程的一种重要方法.本文首先证明了双参数C_0半群在有界扰动下生成一个双参数C_0半群;其次证明了如果双参数C_0半群是直接范数连续的,那么在有界扰动下生成的双参数C_0半群也是直接范数连续的. 相似文献
15.
The aim of this paper is to study a class of right pp semigroups, so-called pseudo-C- rpp semigroups. After obtaining some characterizations of pseudo-C-rpp semigroups, we establish a construction of such semigroups in terms of left normal bands and right C-rpp semigroups. In particular, a special case is considered. 相似文献
16.
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. 相似文献
17.
《代数通讯》2013,41(5):1993-2011
In this paper, we introduce the concepts of 0-minimal ideals, 0-simple ordered semigroups, Rees factor ordered semigroups, natural QO-homomorphisms, quotient principal factors and semisimple ordered semigroups, and discuss characterizations, properties and relationships concerning them. Moreover, we generalize the principal series theory and relative ideal series theory of semigroups (without order) to general ordered semigroups and semisimple ordered semigroups, respectively. 相似文献
18.
Abstract. In this paper we investigate the structure of semigroups with the ideal retraction property i.e., semigroups which are not
simple and have the property that each ideal is a homomorphic retract of the semigroup.
We present examples to show that the ideal retraction property is neither hereditary nor productive. That this property is
preserved by homomorphisms is established for some classes of semigroups, but the general question remains open.
The classes of semigroups investigated in this paper are separative semigroups, ideal semigroups, semilattices, cyclic semigroups,
nil semigroups, and Clifford semigroups.
It is established that a semigroup with zero 0 which is expressible as a direct sum of each ideal and a dual ideal (complement
with 0 adjoined) has the ideal retraction property. The converse holds for ideal semigroups, and an example is presented which
demonstrates that the converse does not hold in general. 相似文献
19.
具有弱正规幂等元的富足半群的结构 总被引:7,自引:1,他引:6
本文研究含弱正规幂等元的富足半群.在给出这类半群的若干特征后,建立了具有弱正规幂等元的富足半群的结构.作为应用,给出具有正规幂等元的富足半群和具有(弱)正规幂等元的拟适当半群的结构. 相似文献
20.
We investigate the dynamics of semigroups of transcendental entire functions using Fatou–Julia theory. Several results of the dynamics associated with iteration of a transcendental entire function have been extended to transcendental semigroups. We provide some condition for connectivity of the Julia set of the transcendental semigroups. We also study finitely generated transcendental semigroups, abelian transcendental semigroups and limit functions of transcendental semigroups on its invariant Fatou components. 相似文献