• Honam Mathematical Journal
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• v.38 no.4
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• pp.795-807
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• 2016

More general form of an (${\in},{\in}{\vee}q_k$)-fuzzy subsemigroup is considered. The notions of (${\in},q^{\delta}_k$)-fuzzy subsemigroup, ($q^{\delta}_0,{\in}{\vee}q^{\delta}_k$)-fuzzy subsemigroup and (${\in},{\in}{\vee}q^{\delta}_k$)-fuzzy subsemigroup are introduced, and related properties are investigated. Characterizations of an (${\in},{\in}{\vee}q^{\delta}_k$)-fuzzy subsemigroup are considered. Conditions for an (${\in},{\in}{\vee}q^{\delta}_k$)-fuzzy subsemigroup to be a fuzzy subsemigroup are provided. Relations between ($q^{\delta}_0,{\in}{\vee}q^{\delta}_k$)-fuzzy subsemigroup, (${\in},q^{\delta}_k$)-fuzzy subsemigroup and (${\in},{\in}{\vee}q^{\delta}_k$)-fuzzy subsemigroup are discussed.

• The Pure and Applied Mathematics
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• v.20 no.2
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• pp.117-127
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• 2013

As a generalization of fuzzy subsemigroups, the notion of ${\varepsilon}$-generalized fuzzy subsemigroups is introduced, and several properties are investigated. A condition for an ${\varepsilon}$-generalized fuzzy subsemigroup to be a fuzzy subsemigroup is considered. Characterizations of ${\varepsilon}$-generalized fuzzy subsemigroups are established, and we show that the intersection of two ${\varepsilon}$-generalized fuzzy subsemigroups is also an ${\varepsilon}$-generalized fuzzy subsemigroup. A condition for an ${\varepsilon}$-generalized fuzzy subsemigroup to be ${\varepsilon}$-fuzzy idempotent is discussed. Using a given ${\varepsilon}$-generalized fuzzy subsemigroup, a new ${\varepsilon}$-generalized fuzzy subsemigroup is constructed. Finally, the fuzzy extension of an ${\varepsilon}$-generalized fuzzy subsemigroup is considered.

• Honam Mathematical Journal
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• v.27 no.1
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• pp.31-41
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• 2005

Given a set ${\Omega}$, the notion of an ${\Omega}$-bifuzzy subsemigroup in semigroups is given, and some properties are investigated. Homomorphic image and inverse image of an ${\Omega}$-bifuzzy subsemigroup are considered.

• Kyungpook Mathematical Journal
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• v.54 no.4
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• pp.607-617
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• 2014

Let S = C(r,m), the finite cyclic semigroup with index r and period m. Each subsemigroup of S is cyclic if and only if either r = 1; r = 2; or r = 3 with m odd. For $r{\neq}1$, the maximum value of the minimum number of elements in a (minimal) generating set of a subsemigroup of S is 1 if r = 3 and m is odd; 2 if r = 3 and m is even; (r-1)/2 if r is odd and unequal to 3; and r/2 if r is even. The number of cyclic subsemigroups of S is $r-1+{\tau}(m)$. Formulas are also given for the number of 2-generated subsemigroups of S and the total number of subsemigroups of S. The minimal generating sets of subsemigroups of S are characterized, and the problem of counting them is analyzed.

• Communications of the Korean Mathematical Society
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• v.28 no.2
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• pp.225-229
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• 2013

According to the paper in [3], the kernel of an ordered semigroup S is a completely regular subsemigroup of S. In this note we show that the kernel of an ordered semigroup S is not a completely regular subsemigroup of S, in general.

• Bulletin of the Korean Mathematical Society
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• v.44 no.2
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• pp.359-367
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• 2007

We consider the intuitionistic fuzzification of the concept of several ${\Gamma}$-ideals in a ${\Gamma}$-semigroup S, and investigate some properties of such ${\Gamma}$-ideals.

• Communications of the Korean Mathematical Society
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• v.30 no.4
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• pp.349-361
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• 2015

A fence is an ordered set that the order forms a path with alternating orientation. Let F = (F;${\leq}$) be a fence and let OT(F) be the semigroup of all order-preserving self-mappings of F. We prove that OT(F) is coregular if and only if ${\mid}F{\mid}{\leq}2$. We characterize all coregular elements in OT(F) when F is finite. For any subfence S of F, we show that the set COTS(F) of all order-preserving self-mappings in OT(F) having S as their range forms a coregular subsemigroup of OT(F). Under some conditions, we show that a union of COTS(F)'s forms a coregular subsemigroup of OT(F).

• Bulletin of the Korean Mathematical Society
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• v.40 no.3
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• pp.531-536
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• 2003

We discuss the roughness of $\Gamma$-subsemigroups and ideals/bi-ideals in $\Gamma$-semigroups.

• Communications of the Korean Mathematical Society
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• v.21 no.3
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• pp.587-593
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• 2006

The notion of intuitionistic fuzzy graphs is introduced. We show how to associate an intuitionistic fuzzy sub(semi)group with an intuitionistic fuzzy graph in a natural way.

• Journal of the Chungcheong Mathematical Society
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• v.22 no.2
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• pp.235-243
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• 2009

In this paper, we introduce the notion of intuitionistic fuzzy semiprimality in an ordered semigroup, which is an extension of fuzzy semiprimality and investigate some properties of intuitionistic fuzzification of the concept of several ideals.