Results 11 to 20 of about 50 (50)
On the inverse image of Baire spaces
International Journal of Mathematics and Mathematical Sciences, Volume 20, Issue 3, Page 423-432, 1997., 1996 In 1961, Z. Frolik proved that if f is an open and continuous mapping of a metrizable separable space X onto Baire space Y and if the point inverses are Baire spaces, then X is a Baire space. We give a generalization to semi‐continuous and semi‐open mapping of this theorem and extended it to the several types of mappings.
Mustafa Çiçek
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Convergence and stability of generalized φ-weak contraction mapping in CAT(0) spaces
Open Mathematics, 2017 The aim of this paper is to prove some fixed point results for generalized φ-weak contraction mapping and study a new concept of stability which is called comparably almost T-stable by using iterative schemes in CAT(0) spaces.
Kim Kyung Soo
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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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A note on maximally resolvable spaces
International Journal of Mathematics and Mathematical Sciences, Volume 13, Issue 3, Page 513-516, 1990., 1989 A.G. El′kin [1] poses the question as to whether any uncountable cardinal number can be the dispersion character of a Hausdorff maximally resolvable space. In this note we prove that every cardinal number ℵ ≥ ℵ1 can be the dispersion character of a metric (hence, maximally resolvable) connected, locally connected space.
V. Tzannes
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A quasitopos containing CONV and MET as full subcategories
International Journal of Mathematics and Mathematical Sciences, Volume 11, Issue 3, Page 417-438, 1988., 1987 We show that convergence spaces with continuous maps and metric spaces with contractions, can be viewed as entities of the same kind. Both can be characterized by a limit function λ which with each filter ℱ associates a map λℱ from the underlying set to the extended positive real line. Continuous maps and contractions can both be characterized as limit
E. Lowen, R. Lowen
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Locally n-Connected Compacta and UVn-Maps
Analysis and Geometry in Metric Spaces, 2015 We provide a machinery for transferring some properties of metrizable ANR-spaces to metrizable LCn-spaces. As a result, we show that for completely metrizable spaces the properties ALCn, LCn and WLCn coincide to each other.
Valov V.
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On q`‐Rung Orthopair Neutrosophic Metric Spaces and Topological Properties
Journal of Applied Mathematics, Volume 2025, Issue 1, 2025.In this paper, we introduce the novel structure of the q`‐rung orthopair neutrosophic metric space (q`‐RˇONM∧S), which unifies and extends the frameworks of q`‐rung orthopair fuzzy sets and neutrosophic metric spaces. The proposed model incorporates membership, nonmembership, and indeterminacy degrees within a q`‐rung orthopair framework, thereby ...
N. Muthulakshmi +4 more
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Necessary and sufficient conditions for distances on the real line
Analysis and Geometry in Metric SpacesWhen dealing with certain mathematical problems, it is sometimes necessary to show that some function induces a metric on a certain space. When this function is not a well renowned example of a distance, one has to develop very particular arguments that ...
Labora Daniel Cao +3 more
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Journal of Mathematics, Volume 2025, Issue 1, 2025.In this study, we introduce a bipolar interval‐valued intuitionistic fuzzy (BIVIF) norm, projection, and bidirectional projection measure within the framework of BIVIF topological spaces. These tools enable us to handle ambiguity with greater accuracy, calculate relationships between sets more effectively, and make rational decisions in uncertain ...
Suganya Manivannan +4 more
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On monoids of metric preserving functions
Frontiers in Applied Mathematics and StatisticsLet X be a class of metric spaces and let PX be the set of all f : [0, ∞) → [0, ∞) preserving X, i.e., (Y, f ∘ ρ) ∈ X whenever (Y, ρ) ∈ X. For arbitrary subset A of the set of all metric preserving functions, we show that the equality PX = A has a ...
Viktoriia Bilet +2 more
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