Results 11 to 20 of about 27,754 (248)
Coverages on inverse semigroups [PDF]
Semigroup Forum, 2020 First we give a definition of a coverage on a inverse semigroup that is weaker than the one gave by a Lawson and Lenz and that generalizes the definition of a coverage on a semilattice given by Johnstone. Given such a coverage, we prove that there exists a pseudogroup that is universal in the sense that it transforms cover-to-join idempotent-pure maps ...
Gilles G. de Castro
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On locally compact semitopological O-bisimple inverse ω-semigroups
Topological Algebra and its Applications, 2018 We describe the structure of Hausdorff locally compact semitopological O-bisimple inverse ω- semigroups with compact maximal subgroups. In particular, we show that a Hausdorff locally compact semitopological O-bisimple inverse ω-semigroup with a compact ...
Gutik Oleg
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Amenable actions of inverse semigroups [PDF]
, 2015 We say that an action of a countable discrete inverse semigroup on a locally compact Hausdorff space is amenable if its groupoid of germs is amenable in the sense of Anantharaman-Delaroche and Renault. We then show that for a given inverse semigroup $S$,
RUY EXEL, CHARLES STARLING
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Topological graph inverse semigroups [PDF]
Topology and its Applications, 2016 25 pages.
Zachary Mesyan +3 more
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Revisiting Hazard Ratios: Can We Define Causal Estimands for Time-Dependent Treatment Effects? [PDF]
Biom JABSTRACT In this paper, some aspects concerning the causal interpretation of hazard contrasts are revisited. It is first investigated, in which sense the hazard ratio constitutes a causal effect. It is demonstrated that the hazard ratio at a timepoint t$t$ represents a causal effect for the population at baseline, but in general not for any population ...
Edelmann D.
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A simplification of D'Alarcao's idempotent separating extensions of inverse semigroups [PDF]
International Journal of Mathematics and Mathematical Sciences, 1978 In [2] D'Alarcao states necessary and sufficient conditions for the attainment of an idempotent-separating extension of an inverse semigroup. To do this D'Alarcao needed essentially three mappings satisfying thirteen conditions.
Constance C. Edwards
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(b, c)-inverse, inverse along an element, and the Schützenberger category of a semigroup [PDF]
Categories and General Algebraic Structures with Applications, 2021 We prove that the (b, c)-inverse and the inverse along an element in a semigroup are actually genuine inverse when considered as morphisms in the Schützenberger category of a semigroup. Applications to the Reverse Order Law are given.
Xavier MARY
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Finite coverings of semigroups and related structures [PDF]
International Journal of Group Theory, 2023 For a semigroup $S$, the covering number of $S$ with respect to semigroups, $\sigma_s(S)$, is the minimum number of proper subsemigroups of $S$ whose union is $S$.
Casey Donoven, Luise-Charlotte Kappe
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Pettis property for Polish inverse semigroups
Applied General Topology, 2023 We study a property about Polish inverse semigroups similar to the classical theorem of Pettis about Polish groups. In contrast to what happens with Polish groups, not every Polish inverse semigroup have the Pettis property.
Karen Arana +2 more
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Journal of Noncommutative Geometry, 2023 In this work, the notion of a quantum inverse semigroup is introduced as a linearized generalization of inverse semigroups. Beyond the algebra of an inverse semigroup, which is the natural example of a quantum inverse semigroup, several other examples of this new structure are presented in different contexts; those are related to Hopf algebras, weak ...
Marcelo Muniz Alves +2 more
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