Results 81 to 90 of about 122,444 (130)

Weakly $$B$$ B -orthodox semigroups

Periodica Mathematica Hungarica, 2014
In the introduction the author has written that ``the article [J. Algebra 368, 209-230 (2012; Zbl 1275.20067)] by \textit{V. Gould} and \textit{Y. Wang} is the first of three in which we investigate the correspondence between algebraic structures and ordered categories, in the sense of Ehresmann-Schein-Nambooripad\dots.
Yanhui Wang
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On U-orthodox semigroups

Science in China Series A: Mathematics, 2009
Let \(S\) be a semigroup with the set of idempotents \(E(S)\). For \(a\in S\) and a non-empty subset \(U\subseteq E(S)\) denote \(U_a^r=\{u\in U\mid au=a\}\) and define relation \(\widetilde{\mathcal L}^U\) by \(a\widetilde{\mathcal L}^Ub\Leftrightarrow U_a^r=U_b^r \); definition of \(\widetilde{\mathcal R}^U\) is dual.
Ren, Xue-Ming, Wang, Yan-Hui, Shum, Kar Ping   +2 more
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Congruences on orthodox semigroups II

Journal of the Australian Mathematical Society, 1972
If ρ is a congruence on a regular semigroup S, then the kernel of ρ is defined to be the set of ρ-classes which contain idempotents of S. Preston [7] has proved that two congruences on a regular semigroup coincide if and only if they have the same kernel: this naturally poses the problem of characterizing the kernel of a congruence on a regular ...
J. Meakin
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STANDARD REPRESENTATIONS OF ORTHODOX SEMIGROUPS

Communications in Algebra, 2005
Abstract Orthodox semigroups have been studied by many authors, in particular by Hall, Yamada and Petrich. In this paper, we give the standard representation of orthodox semigroups and investigate various e-varieties of orthodox semigroups which are determined by the standard representations.
Yong He, Yuqi Guo, K.P. Shum
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ON E-UNITARY COVERS OF ORTHODOX SEMIGROUPS

International Journal of Algebra and Computation, 1993
In this paper we prove that each orthodox semigroup S has an E-unitary cover embeddable into a semidirect product of a band B by a group where B belongs to the band variety generated by the band of idempotents in S. This result is related to an embeddability question on E-unitary regular semigroups raised previously.
M. Szendrei
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Orthodox semigroups and quasi-inverse semigroups

Suwimon Gawgirdwiboon
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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.
Chen, J. F., Cuo, Y. Q.
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Almost Factorizable Orthodox Semigroups

Semigroup Forum, 2006
In this paper, we investigate idempotent separating and arbitrary homomorphic images of semidirect products of bands by groups. We give characterizations for idempotent separating homomorphic images of semidirect products, and show that the class of all idempotent separating homomorphic images is strictly contained in the class of all homomorphic ...
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Semiprimitivity of Orthodox Semigroup Algebras

Communications in Algebra, 2016
Let S be a finite orthodox semigroup or an orthodox semigroup where the idempotent band E(S) is locally pseudofinite. In this paper, by using principal factors and Rukolaǐne idempotents, we show that the contracted semigroup algebra R0[S] is semiprimitive if and only if S is an inverse semigroup and R[G] is semiprimitive for each maximal subgroup G of ...
Yingdan Ji, Yanfeng Luo
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Applications of the Hall-Yamada approach to orthodox semigroups

, 2021
T. Newton
semanticscholar   +1 more source