Results 171 to 180 of about 24,434 (204)

ORTHODOX TRANSVERSALS OF REGULAR SEMIGROUPS

International Journal of Algebra and Computation, 2001
Orthodox transversals were introduced by the first author as a generalization of inverse transversals [Comm. Algebra 27(9) (1999), pp. 4275–4288]. One of our aims in this note is to consider the general case of orthodox transversals. The main results are on the sets I and Λ, two components of regular semigroups with orthodox transversals.
J. F. Chen, Y. Q. Cuo
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T-Classification of Regular Semigroups

Semigroup Forum, 2002
The author proposes a scheme to classify regular semigroups and takes a first step in that direction. On the congruence lattice of any regular semigroup \(S\) are defined two relations, \(K\) and \(T\), the latter a congruence, the former only meet-preserving, in general.
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A class of regular semigroups with regular *- transversals

Semigroup Forum, 2002
A regular semigroup \(S\) is called a regular \(*\)-semigroup if there is a unary operation \(*\) which satisfies the following three conditions: (i) \(xx^*x=x\), (ii) \((x^*)^*=x\), and (iii) \((xy)^*=y^*x^*\), for any \(x,y\in S\) [\textit{T. E. Nordahl, H. E. Scheiblich}, Semigroup Forum 16, 369-377 (1978; Zbl 0408.20043)]. If there a subsemigroup \(
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A Characterization of *-Congruences on a Regular *-Semigroup

Semigroup Forum, 1998
A semigroup \(S\) with a unary operation \(*\colon S\to S\) satisfying the identities \((x^*)^*=x\) and \((xy)^*=y^*x^*\) is called a *-semigroup. A *-semigroup \(S\) is a regular *-semigroup if also the identity \(x=xx^*x\) holds on \(S\). The symbol \(\Lambda^*(S)\) denotes the lattice of all *-congruences on a regular *-semigroup \(S\).
Chae, Younki, Lee, Sang Youl, Park, Chan-Young   +2 more
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REGULAR SEMIGROUPS WITH INVERSE TRANSVERSALS

The Quarterly Journal of Mathematics, 1983
An inverse subsemigroup T of a regular semigroup S is said to be an inverse transversal of S if T contains precisely one inverse of each element of S. Constructions based on the regular semigroup consisting of all regular elements of a Rees matrix semigroup over an inverse semigroup are used to establish the paper's main results.
McAlister, D. B., McFadden, R. B.
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Stability of C-regularized Semigroups

Acta Mathematica Sinica, English Series, 2004
Let \(X\) be a Banach space, let \(T=\{T(t)\}_{t \geq 0}\) be a bounded \(C\)-regularized semigroup generated by \(A\), where \(C\) is a bounded injective linear operator on \(X\) such that \(R(C)\) is dense in \(X\). Denoting by \(\sigma_u(A, Cx)\) the set of all points \(\lambda \in i {\mathbb R}\) such that \((\lambda - A)^{-1}Cx\) cannot be ...
Li, Miao, Zheng, Quan
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Orders in completely regular semigroups

Mathematika, 2001
A classic theorem of semigroup theory is that a semigroup \(S\) has a group of quotients if and only if it is reversible and cancellative. From the perspective of the group, it contains \(S\) as an ``order''. Generalizing from both this situation and from ring theory, a semigroup \(S\) is an order in another semigroup \(Q\) if every element in \(Q ...
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℘-Regular semigroups

Semigroup Forum, 1989
M. Yamada, M. K. Sen
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The regular part of a semigroup of transformations with restricted range

Semigroup Forum, 2011
Jintana Sanwong
exaly  

Regular congruences on an E-inversive semigroup

Semigroup Forum, 2007
Yanfeng Luo
exaly