• Kyungpook Mathematical Journal
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• 제45권2호
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• pp.221-230
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• 2005

In this paper, we define a multifunction $F:X{\rightarrow}Y$ to be upper (lower) Z -supercontinuous if $F^{+}(V)(F^{-}(V))$ is z-open in X for every open set V of Y. We obtain some characterizations and several properties concerning upper (lower) Z-supercontinuous multifunctions.

• East Asian mathematical journal
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• 제23권1호
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• pp.9-22
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• 2007

New classes of multifunctions called fuzzy upper and fuzzy lower semi-irresolute (semi-continuous) multifunctions in fuzzy topological spaces are introduced in this paper. We also obtain some characterizations of this class and some basic interesting properties of such fuzzy multifunctions. We discuss mutual relationship and also relationship with other existing such multifunctions.

• 대한수학회지
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• 제45권3호
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• pp.841-858
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• 2008

In this paper, we introduce two classes of generalized variational-like inequalities with compositely monotone multifunctions in Banach spaces. Using the KKM-Fan lemma and the Nadler's result, we prove the existence of solutions for generalized variational-like inequalities with compositely relaxed ${\eta}-{\alpha}$ monotone multifunctions in reflexive Banach spaces. On the other hand we also derive the solvability of generalized variational-like inequalities with compositely relaxed ${\eta}-{\alpha}$ semimonotone multi functions in arbitrary Banach spaces by virtue of the Kakutani-Fan-Glicksberg fixed-point theorem. The results presented in this paper extend and improve some earlier and recent results in the literature.

• Journal of applied mathematics & informatics
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• 제35권3_4호
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• pp.323-330
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• 2017

Recently Samet, Vetro and Vetro introduced the notion of ${\alpha}$-${\Psi}$-contractive type mappings and initiated some fixed point theorems in complete metric spaces. The notion of ${\alpha}_*$ - ${\Psi}$-contractive multifunctions and initiated some fixed point results by Hasanzade Asl et. al. [8]. In this paper, we introduced the notion of ${\alpha}_*$ - ${\Psi}$-contractive multifunctions in a fuzzy metric space and gave fixed point results for these multifunctions in complete fuzzy metric spaces. We also obtain a fixed point results for self-maps in complete fuzzy metric spaces satisfying contractive condition.

• 대한수학회보
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• 제41권4호
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• pp.647-656
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• 2004

In this paper, by using operations, some characterizations and some properties of fuzzy lower and upper continuous multifunctions and its weaker and stronger forms including fuzzy lower and upper weakly continuous, fuzzy lower and upper ${\theta}-continuous$, fuzzy lower and upper strongly ${\theta}-continuous$, fuzzy lower and upper almost strongly ${\theta}-continuous$, fuzzy lower and upper weakly ${\theta}-continuous$, fuzzy lower and upper almost continuous, fuzzy lower and upper super continuous, fuzzy lower and upper ${\delta}-continuous$, are presented.

• 대한수학회보
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• 제49권2호
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• pp.249-262
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• 2012

In this paper, under some suitable conditions and in virtue of a selection which depends on a vector-valued function and a feasible set map, the sensitivity analysis of a class of implicit multifunctions is investigated. Moreover, by using the results established, the solution sets of parametric vector optimization problems are studied.

• 대한수학회지
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• 제29권1호
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• pp.191-208
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• 1992

• 대한수학회지
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• 제27권2호
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• pp.185-192
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• 1990

• 대한수학회지
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• 제29권2호
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• pp.333-339
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• 1992

• Kyungpook Mathematical Journal
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• 제24권2호
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• pp.179-202
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• 1984