• Journal of the Chungcheong Mathematical Society
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• v.32 no.1
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• pp.127-138
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• 2019

In this paper, I investigate a stability of the following set-valued functional equation $$f(x+3y){\oplus}10f(x+y){\oplus}7f(-x){\oplus}5f(x-y)=5f(x+2y){\oplus}f(x){\oplus}f(2x){\oplus}f(x-2y)$$ in the sense of P. $G{\check{a}}vruta$.

• Honam Mathematical Journal
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• v.41 no.2
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• pp.391-402
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• 2019

In this paper, I prove the stability of the following set-valued functional equation $$f(x+2y){\oplus}f(x-2y){\oplus}3f(2x){\oplus}f(-2x)\\{\hspace{100}}=4f(x+y){\oplus}4f(x-y){\oplus}10f(x)$$ by employing the direct method in the sense of Hyers and Ulam.

• Communications of the Korean Mathematical Society
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• v.25 no.1
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• pp.129-137
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• 2010

In this paper, we introduce and study a system of nonlinear set-valued implicit variational inclusions (SNSIVI) with relaxed cocoercive mappings in real Banach spaces. By using resolvent operator technique for M-accretive mapping, we construct a new class of iterative algorithms for solving this class of system of set-valued implicit variational inclusions. The convergence of iterative algorithms is proved in q-uniformly smooth Banach spaces. Our results generalize and improve the corresponding results of recent works.

• Korean Journal of Logic
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• v.18 no.1
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• pp.65-83
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• 2015

This paper deals with non-algebraic Kripke-style semantics for three-valued paraconsistent logic: set-theoretical Kripke-style semantics. We first recall two three-valued paraconsistent systems. We next introduce set-theoretical Kripke-style semantics for them.

• The Pure and Applied Mathematics
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• v.11 no.3
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• pp.231-242
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• 2004

In this paper, we introduce weakly relaxed $\alpha$-pseudomonotonicity and weakly relaxed $\alpha$-semi-pseudomonotonicity of set-valued maps. Using the KKM technique, we obtain existence of solutions to the variational-like inequalities with weakly relaxed $\alpha$-pseudomor.otone set-valued maps in reflexive Banach spaces. We also present the solvability of the variational-like inequalities with weakly relaxed $\alpha$-semi-pseudomonotone set-valued maps in arbitrary Banach spaces using Kakutani-Fan-Glicksberg fixed point theorem.

• Journal of applied mathematics & informatics
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• v.6 no.1
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• pp.265-272
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• 1999

In this paper we define generalized concepts of cardinal-ity of a fuzzy-valued function and obtained some properties of these new concepts.

• Honam Mathematical Journal
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• v.29 no.2
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• pp.223-244
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• 2007

We introduce the notions of interval-valued fuzzy semipreopen sets (mappings), interval-valued fuzzy semi-pre interior and interval-valued fuzzy semi-pre-continuous mappings by using the notion of interval-valued fuzzy sets. We also investigate related properties and characterize interval-valued fuzzy semi-preopen sets (mappings) and interval-valued fuzzy semi-precontinuous mappings.

• Journal of the Korean Mathematical Society
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• v.37 no.5
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• pp.849-856
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• 2000

We give a new saddle point theorem for vector-valued functions on an admissible compact convex set in a topological vector space under weak condition that is the semicontinuity of two function scalarization and acyclicty of the involved sets. As application, we obtain the minimax theorem.

• Journal of applied mathematics & informatics
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• v.28 no.3_4
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• pp.639-649
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• 2010

In this paper, a definition of interval-valued fuzzy regular language (IVFRL) is proposed and their related properties studied. A model of finite automaton (DFA and NDFA) with interval-valued fuzzy transitions is proposed. Acceptance of interval-valued fuzzy regular language by the finite automaton (DFA and NDFA) with interval-valued fuzzy transitions are examined. Moreover, a definition of finite automaton (DFA and NDFA) with interval-valued fuzzy (final) states is proposed. Acceptance of interval-valued fuzzy regular language by the finite automaton (DFA and NDFA) with interval-valued fuzzy (final) states are also discussed. It is observed that, the model finite automaton (DFA and NDFA) with interval-valued fuzzy (final) states is more suitable than the model finite automaton (DFA and NDFA) with interval-valued fuzzy transitions for recognizing the interval-valued fuzzy regular language. In the end, interval-valued fuzzy regular expressions are defined. We can use the proposed interval-valued fuzzy regular expressions in lexical analysis.

• Journal of applied mathematics & informatics
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• v.16 no.1_2
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• pp.429-443
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• 2004

In this paper, using Zhang, Guo and Liu's comments in [17], we define interval-valued functionals and investigate their properties. Furthermore, we discuss some applications of interval-valued Choquet expectations.