Results 51 to 60 of about 687 (157)

A topological approach for rough semigroups

AIMS Mathematics
This study presents a novel approach to defining topological rough semigroups on an approximation space. The concepts of topological space and rough semigroup are naturally combined to achieve this goal.
Nurettin Bağırmaz
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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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Constructions of positive commutative semigroups on the plane, II

International Journal of Mathematics and Mathematical Sciences, 1985
A positive semiroup is a topological semigroup containing a subsemigroup N isomorphic to the multiplicative semigroup of nonnegative real numbers, embedded as a closed subset of E2 in such a way that 1 is an identity and 0 is a zero.
Reuben W. Farley
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A bridge theorem for the entropy of semigroup actions

Topological Algebra and its Applications, 2020
The topological entropy of a semigroup action on a totally disconnected locally compact abelian group coincides with the algebraic entropy of the dual action.
Bruno Anna Giordano
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Homotopy theory for topological semigroups

Topology and its Applications, 2002
Uvodi se teorija homotopije za topološke polugrupe i istražuju svojstva nekih morfizama nove kategorije.
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A Fibering Theorem for Topological Semigroups [PDF]

Proceedings of the American Mathematical Society, 1963
The theorem of this paper has appeared under stronger hypotheses and sometimes with weaker conclusions a number of times [1; 2; 3 ], and was known to Koch (in approximately the form of [2]) in 1959 (unpublished). Since it is a useful tool in the study of topological semigroups, and the proof here is simpler, and the theorem stronger than those ...
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A note on conservative measures on semigroups

International Journal of Mathematics and Mathematical Sciences, 1992
Consider (S,B,μ) the measure space where S is a topological metric semigroup and μ a countably additive bounded Borel measure. Call μ conservative if all right translations tx:s→sx, x∈S (which are assumed closed mappings) are conservative with respect (S,
N. A. Tserpes
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An Extension of a result of Csiszar

International Journal of Mathematics and Mathematical Sciences, 1986
We extend the results of Csiszar (Z. Wahr. 5(1966) 279-295) to a topological semigroup S. Let μ be a measure defined on S. We consider the value of α=supKcompactlimn→∞supx∈Sμn(Kx−1). First. we show that the value of α is either zero or one.
P. B. Cerrito
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Some New Results for the Sobolev-Type Fractional Order Delay Systems with Noncompact Semigroup

Journal of Function Spaces, 2020
The topological structure of solution sets for the Sobolev-type fractional order delay systems with noncompact semigroup is studied. Based on a fixed point principle for multivalued maps, the existence result is obtained under certain mild conditions ...
Qiaomin Xiang, Pengxian Zhu
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Enveloping semigroups in topological dynamics

Topology and its Applications, 2007
AbstractThis is a survey of the theory of enveloping semigroups in topological dynamics. We review the, already classical, theory of enveloping semigroups, due mainly to Robert Ellis, and then proceed to describe some new connections which were discovered in the last few years between three seemingly unrelated theories: of enveloping semigroups, of ...
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