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Fuzzy sets, fuzzy s-open and s-closed mappings. (English) Zbl 1211.54004
Summary: Several properties of fuzzy semi-closure and fuzzy semi-interior of fuzzy sets, defined by A. M. Zahran [Fuzzy Sets Syst. 116, No. 3, 353–359 (2000; Zbl 0995.54005)], are established and supported by counterexamples. We also study characterizations and properties of fuzzy semi-open and fuzzy semi-closed sets. Moreover, we define fuzzy s-open and fuzzy s-closed mappings and give some interesting characterizations.
MSC:
54A40Fuzzy topology