• Kyungpook Mathematical Journal
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• v.45 no.4
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• pp.595-602
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• 2005

Here we define Central separable semialgebras and to prove some structure theorems for central separable cancellative, semialgebras over a commutative and cancellative semiring.

• Journal of the Chungcheong Mathematical Society
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• v.20 no.3
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• pp.191-201
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• 2007

In this paper we introduce the notion of congruence on a ternary semigroup and study some interesting properties. We also introduce the notions of cancellative congruence, group congruence and Rees congruence and characterize these congruences in ternary semigroups.

• The Pure and Applied Mathematics
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• v.17 no.1
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• pp.81-86
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• 2010

This paper gives some sorts of weakly cancellative of elements which are to be or not to be left magnifying elements in certain semigroups and gives a semilattice congruence in a weakly separative semigroup.

• Journal of applied mathematics & informatics
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• v.30 no.3_4
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• pp.693-697
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• 2012

In this note, we discuss $N(R,<_R)$-structure in a semiring, and show that if ($R,+,{\cdot}$) is a cancellative $<_+$-stable semiring, then ($R/N(R,<_+),+,{\cdot}$) is a semiring.

• Korean Journal of Mathematics
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• v.7 no.1
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• pp.111-116
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• 1999

In this paper, we introduce the concepts of quasi retract ideals and quasi retract topological semigroups which are weaker than those of retract ideals and retract topological semigroups, respectively. We prove that every $n$-th power ideal of a commutative power cancellative power ideal topological semigroup is a quasiretract ideal.

• Bulletin of the Korean Mathematical Society
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• v.35 no.2
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• pp.259-268
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• 1998

We give several characterizations of a TV-PVMD and we show that the localization R[X;S]$_{N_{\upsilon}}$ of a semigroup ring R[X;S] is a TV-PVMD if and only if R is a TV-PVMD where $N_{\upsilon}\;=\;\{f\;{\in}\;R[X]{\mid}(A_f)_{\upsilon} = R\}$ and S is a torsion free cancellative semigroup with zero.

• Journal of the Korean Mathematical Society
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• v.36 no.1
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• pp.97-107
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• 1999

Given a C-dynamical system (A, G, $\alpha$) with a locally compact group G, two kinds of C-algebras are made from it, called the full C-crossed product and the reduced C-crossed product. In this paper, we extend the theory of the classical C-crossed product to the C-dynamical system (A, G, $\alpha$) with a left-cancellative semigroup M with unit. We construct a new C-algebra A $\alpha$rM, the reduced crossed product of A by the semigroup M under the action $\alpha$ and investigate some properties of A $\alpha$rM.

• Kyungpook Mathematical Journal
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• v.51 no.1
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• pp.37-42
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• 2011

Let M be an R-module and S a semigroup. Our goal is to discuss zero-divisors of the semigroup module M[S]. Particularly we show that if M is an R-module and S a commutative, cancellative and torsion-free monoid, then the R[S]-module M[S] has few zero-divisors of size n if and only if the R-module M has few zero-divisors of size n and Property (A).

• Kyungpook Mathematical Journal
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• v.48 no.3
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• pp.443-455
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• 2008

For an extension $A\;{\subseteq}\;B$ of commutative rings, we present a sufficient conditio for the ring $[[A^{S,\;\leq}]]$ of generalized power series to be weakly normal (resp., stronglyt-closed) in $[[B^{S,\;\leq}]]$, where (S, $\leq$) be a torsion-free cancellative strictly ordered monoid. As a corollary, it can be applied to the ring of power series in infinitely many indeterminates as well as in finite indeterminates.

• Korean Journal of Mathematics
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• v.17 no.2
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• pp.189-196
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• 2009

Let D be an integral domain, and let U be a group of units of D. Let $D^*=D-\{0\}$ and ${\Gamma}=D^*/U$ be the commutative cancellative semigroup under aU+bU=abU. We prove that $Cl(D)=Cl({\Gamma})$ and that D is a PvMD (resp., GCD-domain, Mori domain, Krull domain, factorial domain) if and only if ${\Gamma}$ is a PvMS(resp., GCD-semigroup, Mori semigroup, Krull semigroup, factorial semigroup). Let U=U(D) be the group of units of D. We also show that if D is integrally closed, then $D[{\Gamma}]$, the semigroup ring of ${\Gamma}$ over D, is an integrally closed domain with $Cl(D[{\Gamma}])=Cl(D){\oplus}Cl(D)$; hence D is a PvMD (resp., GCD-domain, Krull domain, factorial domain) if and only if $D[{\Gamma}]$ is.