Results 21 to 30 of about 116 (102)
Closed subsets of compact-like topological spaces
Applied General Topology, 2020 We investigate closed subsets (subsemigroups, resp.) of compact-like topological spaces (semigroups, resp.). We show that each Hausdorff topological space is a closed subspace of some Hausdorff ω-bounded pracompact topological space and describe open ...
Serhii Bardyla, Alex Ravsky
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On the Set Version of Selectively Star‐CCC Spaces
Journal of Mathematics, Volume 2020, Issue 1, 2020., 2020 A space X is said to be set selectively star‐ccc if for each nonempty subset B of X, for each collection U of open sets in X such that B¯⊂∪U, and for each sequence An:n∈ℕ of maximal cellular open families in X, there is a sequence (An : n ∈ ℕ) such that, for each n ∈ ℕ, An∈An and B⊂St∪n∈ℕAn,U. In this paper, we introduce set selectively star‐ccc spaces
Ljubiša D. R. Kočinac +2 more
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A note on bf-spaces and on the distribution of the functor of the Dieudonné completion
Topological Algebra and its Applications, 2021 A subset B of a space X is said to be bounded (in X) if the restriction to B of every real-valued continuous function on X is bounded. A real-valued function on X is called bf-continuous if its restriction to each bounded subset of X has a continuous ...
Sanchis Manuel, Valero Óscar
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Pseudocompact and precompact topological subsemigroups of topological groups
Pracì Mìžnarodnogo Geometričnogo Centru, 2023 It is known that every pseudocompact topological group is precompact, we extend this result to a class of subsemigroup of topological groups. Then we use this results to prove that cancellative locally compact countably compact topological semigroups ...
Julio Cesar Hernandez
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مجلة جامعة الانبار للعلوم الصرفة, 2009 Lindelof spaces, using multifunctions, are given.Our main results are .A space X is z-compact iff for every space Y and z-closed graph multifunction on X into Y the image of every z-closed set in X, is closed in Y. A space X is z-Lindelof iff for every P-
Atallah Th. Al-Ani
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Intermediate rings of complex-valued continuous functions
Applied General Topology, 2021 For a completely regular Hausdorff topological space X, let C(X, C) be the ring of complex-valued continuous functions on X, let C ∗ (X, C) be its subring of bounded functions, and let Σ(X, C) denote the collection of all the rings that lie between C ...
Amrita Acharyya +3 more
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Applied General Topology, 2015 Suppose $F$ is a totally ordered field equipped with its order topology and $X$ a completely $F$-regular topological space. Suppose $\mathcal{P}$ is an ideal of closed sets in $X$ and $X$ is locally-$\mathcal{P}$.
Sudip Kumar Acharyya +2 more
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Endograph Metric and a Version of the Arzelà–Ascoli Theorem for Fuzzy Sets
Mathematics, 2023 In this paper, we provide several Arzelà–Ascoli-type results on the space of all continuous functions from a Tychonoff space X into the fuzzy sets of Rn, (FUSCB(Rn),Hend), which are upper semi-continuous and have bounded support endowed with the ...
Juan J. Font +2 more
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New characterisations of pseudocompact spaces [PDF]
Bulletin of the Australian Mathematical Society, 1988 In this paper, we give a new characterisation of pseudo-compact spaces, namely a space X is pseudocompact if and only if each σ-point finite open cover of X has a finite subfamily whose union is dense. As a corollary, we show that every pseudocompact σ-metacompact (or screenable) space is compact, which sharpens some known results.
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A characterization of pseudocompactness
International Journal of Mathematics and Mathematical Sciences, 1981 It is proved here that a completely regular Hausdorff space X is pseudocompact if and only if for any continuous function f from X to a pseudocompact space (or a compact space) Y, f*ϕ is z-ultrafilter whenever ϕ is a z-ultrafilter on X.
Prabduh Ram Misra, Vinodkumar
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