• 호남수학학술지
• /
• 제30권3호
• /
• pp.557-566
• /
• 2008

In this paper, we introduce the concept of IVF weakly continuity and investigate some characterizations for IVF weakly continuous mappings on the interval-valued fuzzy topological spaces. We introduce and study the concepts of almost IVF compactness and nearly IVF compactness.

• 대한수학회보
• /
• 제36권1호
• /
• pp.33-45
• /
• 1999

In this paper, we are interested in studying weak covering properties in the presence of a countable compact condition. The purpose of this paper is to characterize an ideal weakly $\delta$$\theta$-refinable space and to show that every ideal weakly $\delta$$\theta$-refinable space is isocompact. Also, we consider the behavior under mappings of ideal weakly $\delta$$\theta$-refinable properties and productivity of ideal weakly $\delta$$\theta$-refinable properties.

• Journal of applied mathematics & informatics
• /
• 제28권3_4호
• /
• pp.993-1001
• /
• 2010

In this paper, we introduce the concept of fuzzy weakly r-M continuous function on r-minimal structures and investigate characterizations and properties for such functions.

• 호남수학학술지
• /
• 제30권3호
• /
• pp.435-442
• /
• 2008

We introduce the concepts of weakly ${\gamma}$-continuity, strongly ${\gamma}$-closed graph and ${\gamma}-T_2$ spaces. And we study some characterizations and properties or such concepts.

• 대한수학회보
• /
• 제55권3호
• /
• pp.967-970
• /
• 2018

The aim of this paper is to show that there exists a weakly quasisymmetric homeomorphism $f:(X,d){\rightarrow}(Y,d^{\prime})$ between two locally compact non-complete metric spaces such that $f:(X,d_h){\rightarrow}(Y,d^{\prime}_h)$ is not quasi-isometric, where dh denotes the Gromov hyperbolic metric with respect to the metric d introduced by Ibragimov in 2011. This result shows that the answer to the related question asked by Ibragimov in 2013 is negative.

• East Asian mathematical journal
• /
• 제24권4호
• /
• pp.329-338
• /
• 2008

The aim of this paper is to introduce a new generalization of fuzzy faintly continuous functions called fuzzy faintly pre-continuous functions and also we have introduced and studied weakly fuzzy pre-continuous functions. Several characterizations of fuzzy faintly pre-continuous functions are given and some interesting properties of the above functions are discussed.

• 충청수학회지
• /
• 제36권4호
• /
• pp.279-288
• /
• 2023

We obtain a Chandrabhan type fixed point theorem for a multimap having a non-compact domain and a weakly closed graph, and taking convex values only on a quasi-convex subset of Hausdorff locally convex topological vector space. We introduce the definition of Chandrabhan-set and find a sufficient condition for every countably condensing multimap to have a relatively compact Chandrabhan-set. Finally, we establish a new version of Sadovskii fixed point theorem for multimaps.

• 대한수학회지
• /
• 제13권2호
• /
• pp.151-153
• /
• 1976

• East Asian mathematical journal
• /
• 제32권3호
• /
• pp.365-375
• /
• 2016

In this paper, we study some classes of spaces determined by closure-like operators $[{\cdot}]_s$, $[{\cdot}]_c$ and $[{\cdot}]_k$ etc. which are wider than the class of $Fr{\acute{e}}chet-Urysohn$ spaces or the class of sequential spaces and related spaces. We first introduce a WADS space which is a generalization of a sequential space. We show that X is a WADS and k-space iff X is sequential and every WADS space is C-closed and obtained that every WADS and countably compact space is sequential as a corollary. We also show that every WAP and countably compact space is countably sequential and obtain that every WACP and countably compact space is sequential as a corollary. And we show that every WAP and weakly k-space is countably sequential and obtain that X is a WACP and weakly k-space iff X is sequential as a corollary.

• 한국수학교육학회지시리즈B:순수및응용수학
• /
• 제17권4호
• /
• pp.269-273
• /
• 2010

We introduce the concepts of strongly $s{\gamma}$-closed graph, $s{\gamma}$-compactness and $s{\gamma}-T_2$ space and study the relationships between such concepts and weakly $s{\gamma}$-continuous functions.