Remarks on δ-semi-open sets and δ-preopen sets

• Autorzy: Noiri T.
• Języki publikacji: EN

Abstrakty

EN

It is shown that a subset A of a topological space (X, r) is (^semi-open (resp. preopen) in (X,r) if and only if it is semi-open (resp. preopen) in (X,r.s), where rs denotes the semi-regularization of r. By using this fact, we can obtain several new characterizations of s-closed spaces, semi-connected spaces, and some separation axioms.

Słowa kluczowe

EN

s-normal space; semiconnected; semi-open; preopen sets

• Wydawca: De Gruyter
• Czasopismo: Demonstratio Mathematica
• Rocznik: 2003
• Tom: Vol. 36, nr 4
• Strony: 1007--1020
• Opis fizyczny: Bibliogr. 43 poz.

Twórcy

autor

Noiri T.

• Department of Mathematics, Yatsushiro College of Technology, Yatsushiro, Kumamoto, 866-8501 Japan

Bibliografia

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