Results 31 to 40 of about 1,356 (186)
Mathematical Structures in Computer Science, 2017 A semigroup-based setting for developing Hoare logics and refinement calculi is introduced together with procedures for translating between verification and refinement proofs. A new Hoare logic for multirelations and two minimalist generic verification and refinement components, implemented in an interactive theorem prover, are presented as ...
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Asymptotic expansions for Yosida approximations of semigroups
Lietuvos Matematikos Rinkinys, 2008 In this paper we provide asymptotic expansions for Yosida approximations of contraction semigroups. We also obtain optimal bounds for convergencerate and remainder terms of asymptotic expansions.
Monika Vilkienė
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Picture N-Sets and Applications in Semigroups
International Journal of Analysis and Applications, 2022 In this paper, we study picture N-structures and apply it to semigroups. Moreover, we define picture N-ideals in semigroups and investigate several properties of these ideals in semigroups.
Anusorn Simuen +3 more
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Journal of Algebra, 2014 The action of any group on itself by conjugation and the corresponding conjugacy relation play an important role in group theory. There have been several attempts to extend the notion of conjugacy to semigroups. In this paper, we present a new definition of conjugacy that can be applied to an arbitrary semigroup and it does not reduce to the universal ...
João Araújo +2 more
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Rough semigroups and rough fuzzy semigroups based on fuzzy ideals
Open Mathematics, 2016 In this paper, we firstly introduce a special congruence relation U(μ, t) induced by a fuzzy ideal μ in a semigroup S. Then we define the lower and upper approximations based on a fuzzy ideal in semigroups. We can establish rough semigroups, rough ideals,
Wang Qiumei, Zhan Jianming
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Fixed point properties for semigroups of nonexpansive mappings on convex sets in dual Banach spaces
Annales Universitatis Paedagogicae Cracoviensis: Studia Mathematica, 2018 It has been a long-standing problem posed by the first author in a conference in Marseille in 1990 to characterize semitopological semigroups which have common fixed point property when acting on a nonempty weak* compact convex subset of a dual Banach ...
Anthony To-Ming Lau, Yong Zhang
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Complex Analysis and Operator Theory, 2011 In this paper we consider a semigroup on trigonometric expansions that will be called the Theta semigroup since its kernel is a multiple of the third Jacobi theta function. We study properties of this semigroup and prove that it is a positive diffusion semigroup. We also obtain that its subordinated semigroup is the classical Poisson semigroup.
Urbina, Wilfredo O., Zayed, Ahmed
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Flows on Classes of Regular Semigroups and Cauchy Categories
Journal of Mathematics, 2019 We consider the structure of the flow monoid for some classes of regular semigroups (which are special case of flows on categories) and for Cauchy categories.
Suha Ahmed Wazzan
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Algebras of right ample semigroups
Open Mathematics, 2018 Strict RA semigroups are common generalizations of ample semigroups and inverse semigroups. The aim of this paper is to study algebras of strict RA semigroups.
Guo Junying, Guo Xiaojiang
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On the Semigroup of Bi-Ideals of an Ordered Semigroup
Kragujevac Journal of Mathematics, 2023 The purpose of this paper is to characterize an ordered semigroup S in terms of the properties of the associated semigroup B(S) of all bi-ideals of S. We show that an ordered semigroup S is a Clifford ordered semigroup if and only if B(S) is a semilattice.
Mallick, Susmita, Hansda, Kalyan
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