Results 31 to 40 of about 530 (201)
On certain semigroups of contraction mappings of a finite chain
, 2021 Let [n] = {1, 2, . . . , n} be a finite chain and let Pn (resp. , Tn) be the semigroup of partial transformations on [n] (resp. , full transformations on [n]). Let CPn = {α ∈ Pn : (for all x, y ∈ Dom α) |xα−yα| ≤ |x−y|} (resp. , CT n = {α ∈ Tn : (for all
Zubairu, M.M., Umar, A.
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The Bergman property for semigroups
, 2009 In this article, we study the Bergman property for semigroups and the associated notions of cofinality and strong cofinality. A large part of the paper is devoted to determining when the Bergman property, and the values of the cofinality and strong ...
Ruskuc, N. +7 more
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Morita equivalence of semigroups revisited: Firm semigroups [PDF]
, 2018 We define firm semigroups and firm acts as non-additive analogues of firm rings and firm modules. Using the categories of firm acts we develop Morita theory for firm semigroups.
Laan, V. +5 more
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A TERNARY SEMIGROUP OF MAPPINGS
Demonstratio Mathematica, 1994 The notion of a ternary semigroup of mappings of two sets is given. The author studies the structure of a ternary semigroup of mappings and gives a characterization of the structure of inverses.
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Semigroups of constant maps [PDF]
Journal of the Australian Mathematical Society. Series A. Pure Mathematics and Statistics, 1985 AbstractIn this paper “a map” denotes an arbitrary (everywhere defined, or partial, or even multi-valued) mapping. A map is constant if any two elements belonging to its domain have precisely the same images under this map. We characterize those semigroups which can be isomorphic to semigroups of constant maps or to involuted semigroups of constant ...
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Generating transformation semigroups using endomorphisms of preorders, graphs, and tolerances
, 2010 Let ΩΩ be the semigroup of all mappings of a countably infinite set Ω. If U and V are subsemigroups of ΩΩ, then we write U≈V if there exists a finite subset F of ΩΩ such that the subsemigroup generated by U and F equals that generated by V and F.
Morayne, Michal +11 more
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Maximal subgroups of free idempotent-generated semigroups over the full transformation monoid
, 2011 Let Tn be the full transformation semigroup of all mappings from the set {1, . . . , n} to itself under composition. Let E = E(Tn) denote the set of idempotents of Tn and let e ∈ E be an arbitrary idempotent satisfying |im (e)| = r ≤ n − 2. We prove that
Ruskuc, N. +3 more
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Stability of Viscous Three‐Dimensional Stratified Couette Flow via Dispersion and Mixing
Communications on Pure and Applied Mathematics, EarlyView.ABSTRACT This article explores the stability of stratified Couette flow in the viscous 3d$3d$ Boussinesq equations. In this system, mixing effects arise from the shearing background, and gravity acts as a restoring force leading to dispersive internal gravity waves.
Michele Coti Zelati +2 more
wiley +1 more source
Beyond Regular Semigroups [PDF]
, 2012 The topic of this thesis is the class of weakly U-abundant semigroups. This class is very wide, containing inverse, orthodox, regular, ample, adequate, quasi-adequate, concordant, abundant, restriction, Ehresmann and weakly abundant semigroups.
Wang, Yanhui
core
Generating the full transformation semigroup using order preserving mappings
, 2003 For a linearly ordered set X we consider the relative rank of the semigroup of all order preserving mappings O-X on X modulo the full transformation semigroup Ex. In other words, we ask what is the smallest cardinality of a set A of mappings such that =
Higgins, PM +2 more
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