Results 21 to 30 of about 337 (43)
On star Rothberger spaces modulo an ideal
Applied General TopologyIn this article, we introduce the ideal star-Rothberger property by coupling the notion of a star operator to that of an ideal Rothberger space, after which some of its topological characteristics are analysed. By creating relationships between a numbers
Susmita Sarkar +2 more
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, 2004 We present an example of a compact connected F-space with a continuous real-valued function f for which the union of the interiors of its fibers is not dense.
Hart, Klaas Pieter
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Perfect maps in compact (countably compact) spaces
International Journal of Mathematics and Mathematical Sciences, Volume 18, Issue 4, Page 773-776, 1995., 1993 In this paper, among other results, characterizations of perfect maps in compact Hausdorff(Fréchet, countably compact, Hausdorff) spaces are obtained.
G. L. Garg, Asha Goel
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Measures of Lindelof and separability in approach spaces
International Journal of Mathematics and Mathematical Sciences, Volume 17, Issue 3, Page 597-606, 1994., 1993 In this paper we introduce the notions of separability and Lindelöf in approach spaces and investigate their behaviour under products and subspaces.
R. Baekeland, R. Lowen
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International Journal of Mathematics and Mathematical Sciences, Volume 17, Issue 4, Page 687-692, 1994., 1994 In this paper we study θ‐regularity and its relations to other topological properties. We show that the concepts of θ‐regularity (Janković, 1985) and point paracompactness (Boyte, 1973) coincide. Regular, strongly locally compact or paracompact spaces are θ‐regular.
Martin M. Kovár
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On weaker forms of compactness Lindelöfness and countable compactness
International Journal of Mathematics and Mathematical Sciences, Volume 13, Issue 1, Page 55-59, 1990., 1988 A theory of e‐countable compactness and e‐Lindelöfness which are weaker than the concepts of countable compactness and Lindelöfness respectively is developed. Amongst other results we show that an e‐countably compact space is pseudocompact, and an example of a space which is pseudocompact but not e‐countably compact with respect to any dense set is ...
D. Baboolal, J. Backhouse, R. G. Ori
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Corrigendum to Taxonomies of Model-theoretically Defined Topological Properties [PDF]
, 1991 An error has been found in the cited paper; namely, Theorem 3.1 is ...
Bankston, Paul
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Topological partition relations to the form omega^*-> (Y)^1_2
, 1993 Theorem: The topological partition relation omega^{*}-> (Y)^{1}_{2} (a) fails for every space Y with |Y| >= 2^c ; (b) holds for Y discrete if and only if |Y|
Comfort W. W. +12 more
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Applications of δ‐Open Sets via Separation Axioms, Covering Properties, and Rough Set Models
Journal of Mathematics, Volume 2025, Issue 1, 2025.In this article, we make use of δ‐open sets to establish some topological concepts related to separation axioms and covering properties and to propose novel topological rough set models. We first demonstrate that the classes of regular‐open and δ‐open subsets of a finite topological space are equivalent when this space has the property of ∂(A)∩∂(B)⊆∂(A
Tareq M. Al-Shami +2 more
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International Journal of Mathematics and Mathematical Sciences, Volume 13, Issue 3, Page 507-512, 1990., 1989 An ideal on a set X is a nonempty collection of subsets of X closed under the operations of subset (heredity) and finite unions (additivity). Given a topological space (X, τ) an ideal ℐ on X and A⊆X, ψ(A) is defined as ⋃{U ∈ τ : U − A ∈ ℐ}. A topology, denoted τ*, finer than τ is generated by the basis {U − I : U ∈ τ, I ∈ ℐ}, and a topology, denoted 〈ψ(
T. R. Hamlett, David Rose
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