共查询到20条相似文献,搜索用时 156 毫秒
1.
引入了0-恰当半群的概念,它是一种特殊的逆半群.给出了0-恰当半群的等价刻划.讨论具有幂等半格的右0-恰当半群上含于(够)0的最大同余关系μL和具有幂等半格的0-恰当半群上含于(形)0的最大同余关系μ.证明如果S是一个具有幂等半格E的右0-A型半群,则S/μL≌E当且仅当S是一个S0左逆的左消含幺半群的强半格.进一步证明了,如果S是一个具有幂等半格E的0-恰当半群,则S/μ≌E当且仅当S是一个S0逆的消去含幺半群的强半格. 相似文献
2.
半群上Rees矩阵半群的半格的结构 总被引:1,自引:0,他引:1
曹永林 《纯粹数学与应用数学》1998,(2)
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. 相似文献
3.
幺半群上的Rees矩阵半群的半格的结构 总被引:1,自引:0,他引:1
曹永林 《纯粹数学与应用数学》1998,14(2):28-32
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。 相似文献
4.
5.
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. 相似文献
6.
求证具有强半格结构的完全正则半群成为P-完全正则半群的充分条件.利用半群的强半格结构以及同余的性质.完全单半群的强半格-正规群带是P-完全正则半群.矩形群的强半格正规纯正群类ONBG,左群的强半格左正规纯整群类LONBG,群的强半格Clifford半群类,矩形带的强半格正规带类NB,都具有性质P. 相似文献
7.
8.
9.
10.
π-逆半群是广义正则半群,研究它的π-逆子半群格是非常自然的.本文首先讨论了一个π-逆半群的π逆子半群格的直积分解;然后通过引进πU-链的概念刻划了π-逆子半群格是模格的π-逆半群的性质及特征. 相似文献
11.
A left GC-lpp semigroup S is called split if the natural homomorphism γb of S onto S/γ induced by γ is split.It is proved that a left GC-lpp semigroup is split if and only if it has a left adequate transversal.In particular,a construction theorem for split left GC-lpp semigroups is established. 相似文献
12.
Let V be a linear space over a field F with finite dimension, L(V) the semigroup, under composition, of all linear transformations from V into itself. Suppose that V = V1 V2 ... Vm is a direct sum decomposition of V, where V1,V2,..., Vm are subspaces of V with the same dimension. A linear transformation f ∈ L(V) is said to be sum-preserving, if for each i (1 ≤ i ≤ m), there exists some j (1 ≤ j ≤ m) such that f(Vi) Vj. It is easy to verify that all sum-preserving linear transformations form a subsemigroup of L(V) which is denoted by L (V). In this paper, we first describe Green's relations on the semigroup L (V). Then we consider the regularity of elements and give a condition for an element in L (V) to be regular. Finally, Green's equivalences for regular elements are also characterized. 相似文献
13.
We study groups and semigroups of n x n matrices with the property that each matrix has a fixed point, i.e., 1 is an eigenvalue of each matrix. We show that for n=3 and $n\geq 5$ there are irreducible matrix groups and irreducible semigroups of nonnegative matrices with this property. In fact, for n = 3 we determine the structure of any such semigroup. We also present additional hypotheses implying reducibility. 相似文献
14.
15.
Let
be a dense sub-semigroup of ℝ+, and let X be a separable, reflexive Banach space. This note contains a proof that every weakly continuous contractive semigroup of
operators on X over
can be extended to a weakly continuous semigroup over ℝ+. We obtain similar results for nonlinear, nonexpansive semigroups as well. As a corollary we characterize all densely parametrized
semigroups which are extendable to semigroups over ℝ+.
O.M. Shalit was partially supported by the Gutwirth Fellowship. 相似文献
16.
Let S =∪(Gα : α ∈ E) be a semilattice of groups(i.e., a Cliford semigroup) and n a natural number. E is called an n-element chain of groups if it is an n-element chain. Denote by Cn the set of all n-element chains of groups. In this paper we shall show that for any natural number n, the class of semigroups Cn satisfies the strong isomorphism property. 相似文献
17.
Alexei Vernitski 《Semigroup Forum》2009,78(3):486-497
We prove a number of results related to finite semigroups and their inverse subsemigroups, including the following. (1) A finite
semigroup is aperiodic if and only if it is a homomorphic image of a finite semigroup whose inverse subsemigroups are semilattices.
(2) A finite inverse semigroup can be represented by order-preserving mappings on a chain if and only if it is a semilattice.
Finally, we introduce the concept of pseudo-small quasivariety of finite semigroups, generalizing the concept of small variety. 相似文献
18.
设O→J→A→B→O是一个拟对角扩张.作者证明如果J和B具有Cuntz半群的某些性质,则A也具有相同的半群性质. 相似文献
19.
In this paper we study sub-semigroups of a finite or an infinite zero-divisor semigroup S determined by properties of the zero-divisor graph Γ(S). We use these sub-semigroups to study the correspondence between zero-divisor semigroups and zero-divisor graphs. In particular, we discover a class of sub-semigroups of reduced semigroups and we study properties of sub-semigroups of finite or infinite semilattices with the least element. As an application, we provide a characterization of the graphs which are zero-divisor graphs of Boolean rings. We also study how local property of Γ(S) affects global property of the semigroup S, and we discover some interesting applications. In particular, we find that no finite or infinite two-star graph has a corresponding nil semigroup. 相似文献
20.
首先分别给出单生矩阵半群或者摹群不可约、不可分解以及完全可约的充分必要条件,其次讨论一般域上矩阵半群的可约性的一些条件,最后特别地讨论实数域上矩阵半群的可约性,完全确定了实数域上对称和反对称矩阵组成的不可约交换矩阵半群. 相似文献