Results 11 to 20 of about 68 (65)
More on μ-semi-Lindelöf sets in μ-spaces
Demonstratio Mathematica, 2021 Sarsak [On μ\mu -compact sets in μ\mu -spaces, Questions Answers Gen. Topology 31 (2013), no. 1, 49–57] introduced and studied the class of μ\mu -Lindelöf sets in μ\mu -spaces. Mustafa [μ\mu -semi compactness and
Sarsak Mohammad S.
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The characterizations of upper approximation operators based on special coverings
Open Mathematics, 2017 In this paper, we discuss the approximation operators apr¯NS${\overline {apr} _{NS}}$ and apr¯S${\overline {apr} _S}$ which are based on NS(U) and S.
Wang Pei, Li Qingguo
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Properties of some ∗‐dense‐in‐itself subsets
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 72, Page 3989-3999, 2004., 2004 ℐ‐open sets were introduced and studied by Janković and Hamlett (1990) to generalize the well‐known Banach category theorem. Quasi‐ℐ‐openness was introduced and studied by Abd El‐Monsef et al. (2000). These are ∗‐dense‐in‐itself sets of the ideal spaces. In this note, properties of these sets are further investigated and characterizations of these sets
V. Renuka Devi +2 more
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Kuratowski Monoids of n-Topological Spaces
Topological Algebra and its Applications, 2018 Generalizing the famous 14-set closure-complement Theorem of Kuratowski from 1922, we prove that for a set X endowed with n pairwise comparable topologies Ʈ1 ⊂ · · · ⊂ Ʈn, by repeated application of the operations of complement and closure in the ...
Banakh Taras +5 more
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An extension theorem for sober spaces and the Goldman topology
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 51, Page 3217-3239, 2003., 2003 Goldman points of a topological space are defined in order to extend the notion of prime G‐ideals of a ring. We associate to any topological space a new topology called Goldman topology. For sober spaces, we prove an extension theorem of continuous maps.
Ezzeddine Bouacida +3 more
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γ‐sets and γ‐continuous functions
International Journal of Mathematics and Mathematical Sciences, Volume 31, Issue 3, Page 177-181, 2002., 2002 We introduce a new class of sets, called γ‐sets, and the notion of γ‐continuity and investigate some properties and characterizations. In particular, γ‐sets and γ‐continuity are used to extend known results for semi‐open sets and semi‐continuity.
Won Keun Min
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International Journal of Mathematics and Mathematical Sciences, Volume 32, Issue 7, Page 387-399, 2002., 2002 Neighborhood spaces, pretopological spaces, and closure spaces are topological space generalizations which can be characterized by means of their associated interior (or closure) operators. The category NBD of neighborhood spaces and continuous maps contains PRTOP as a bicoreflective subcategory and CLS as a bireflective subcategory, whereas TOP is ...
D. C. Kent, Won Keun Min
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Regular‐uniform convergence and the open‐open topology
International Journal of Mathematics and Mathematical Sciences, Volume 25, Issue 5, Page 357-360, 2001., 2001 In 1994, Bânzaru introduced the concept of regular‐uniform, or r‐uniform, convergence on a family of functions. We discuss the relationship between this topology and the open‐open topology, which was described in 1993 by Porter, on various collections of functions.
Kathryn F. Porter
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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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A note on the comparison of topologies
International Journal of Mathematics and Mathematical Sciences, Volume 26, Issue 4, Page 233-237, 2001., 2001 A considerable problem of some bitopological covering properties is the bitopological unstability with respect to the presence of the pairwise Hausdorff separation axiom. For instance, if the space is RR‐pairwise paracompact, its two topologies will collapse and revert to the unitopological case.
Martin M. Kovár
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