Results 21 to 30 of about 787,356 (301)

Axiomatic systems of Alexandrov spaces

Journal of Hebei University of Science and Technology, 2017
In order to study internel axiomatic systems and ordered features of Alexandrov spaces, with the help of some existed results in topology and locale theory, by restricting the related structures into Alexandrov setting, some equivalent descriptions are ...
Shanshan ZHANG, Fei LI, Wei YAO
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Galois connections between sets of paths and closure operators in simple graphs

Open Mathematics, 2018
For every positive integer n,we introduce and discuss an isotone Galois connection between the sets of paths of lengths n in a simple graph and the closure operators on the (vertex set of the) graph.
Šlapal Josef
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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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Multipliers in weak Heyting algebras [PDF]

Journal of Mahani Mathematical Research
In this paper, we introduce the notion of multipliers in weak Heyting algebras and investigate some related properties of them. We obtain the relations between multipliers, closure operators, and homomorphisms in weak Heyting algebras.
Shokoofeh Ghorbani
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Primal Structure with Closure Operators and Their Applications

Mathematics, 2023
Acharjee et al. have created a new structure in mathematics called a primal. Therefore, the primary goal of this research was to introduce and explore more primal space features.
Ahmad Al-Omari, Mesfer H. Alqahtani
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gp alpha Kuratowski's Closure Operators in topological spaces

Ratio Mathematica, 2021
In this paper, we introduce and study topological properties of $gp\alpha$-limit points, $gp\alpha$-derived sets, $gp\alpha$-interior, and $gp\alpha$-closure using the concept of $gp\alpha$-open set.
P G Patil, Bhadramma Pattanasgetti
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Closure operators [PDF]

Journal of the Australian Mathematical Society, 1975
A mapping κ: P(X) → P(X) is a quasi-closure operator (see Thron (1966) page 44) if (i) □κ = □, and for all A, B ∈ P(X) we have (ii) A ⊆ Aκ, and (iii) (A ⋓ B)κ = Aκ ∪ Bκ one easily deduces that such operators have the further property: (iv) if A ⊆ B ⊆ X, then Aκ if κ also satisfies: (v) Aκ2 ⊆ Aκ for all A ⊆ X, then κ is called a Kuratowski closure ...
Collyer, P. J., Sullivan, R. P.
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Functors among Relational Variants of Categories Related to L-Fuzzy Partitions, L-Fuzzy Pretopological Spaces and L-Fuzzy Closure Spaces

Axioms, 2020
Various types of topological and closure operators are significantly used in fuzzy theory and applications. Although they are different operators, in some cases it is possible to transform an operator of one type into another.
Jiří Močkoř
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Remarks on Interiors and Closures of Weak Open Sets in Bigeneralized Topological Spaces

Ratio Mathematica, 2022
We establish the relationships between the interior and closure operators among the µij -semiopen, µij -preopen, αµij -open, βµij -open sets in bigeneralized topological ...
M Anees Fathima, Jamuna Rani R
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Lattices of closure operators

Discrete Mathematics, 1998
The system of all closure operators on a set \(V\) forms in a natural way a lattice which is isomorphic to the lattice of all Moore families \((\text{MF}(V),\subseteq)\) of subsets of \(V\). The author shows the existence of a spanning tree for the lattice of Moore families.
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