@Article{Pourmirzaei2016,
author="Pourmirzaei, A.
and Hassanzadeh, M.
and Mashayekhy, B.",
title="ON RELATIVE CENTRAL EXTENSIONS AND COVERING PAIRS",
journal="Journal of Algebraic Systems",
year="2016",
volume="4",
number="1",
pages="1-13",
abstract="Let (G;N) be a pair of groups. In this article, first we con-struct a relative central extension for the pair (G;N) such that specialtypes of covering pair of (G;N) are homomorphic image of it. Second, weshow that every perfect pair admits at least one covering pair. Finally,among extending some properties of perfect groups to perfect pairs, wecharacterize covering pairs of a perfect pair (G;N) under some extraassumptions.",
issn="2345-5128",
doi="10.22044/jas.2016.724",
url="http://jas.shahroodut.ac.ir/article_724.html"
}
@Article{Ebrahimpour2016,
author="Ebrahimpour, M.",
title="SOME REMARKS ON GENERALIZATIONS OF MULTIPLICATIVELY CLOSED SUBSETS",
journal="Journal of Algebraic Systems",
year="2016",
volume="4",
number="1",
pages="15-27",
abstract="Let R be a commutative ring with identity and Mbe a unitary R-module. In this paper we generalize the conceptmultiplicatively closed subset of R and we study some propertiesof these genaralized subsets of M. Among the many results in thispaper, we generalize some well-known theorems about multiplicativelyclosed subsets of R to these generalized subsets of M. Alsowe show that some other well-known results about multiplicativelyclosed subsets of R are not valid for these generalized subsets ofM.",
issn="2345-5128",
doi="10.22044/jas.2016.725",
url="http://jas.shahroodut.ac.ir/article_725.html"
}
@Article{Mirdamadi2016,
author="Mirdamadi, S.E.
and Rezaeezadeh, Gh.R",
title="ON FINITE GROUPS IN WHICH SS-SEMIPERMUTABILITY IS A TRANSITIVE RELATION",
journal="Journal of Algebraic Systems",
year="2016",
volume="4",
number="1",
pages="29-36",
abstract="Let H be a subgroup of a finite group G. We say that H is SS-semipermutable in Gif H has a supplement K in G such that H permutes with every Sylow subgroup X of Kwith (jXj; jHj) = 1. In this paper, the Structure of SS-semipermutable subgroups, and finitegroups in which SS-semipermutability is a transitive relation are described. It is shown thata finite solvable group G is a PST-group if and only if whenever H K are two p-subgroupsof G, H is SS-semipermutable in NG(K).",
issn="2345-5128",
doi="10.22044/jas.2016.726",
url="http://jas.shahroodut.ac.ir/article_726.html"
}
@Article{Mahmoudifar2016,
author="Mahmoudifar, A.",
title="ON COMPOSITION FACTORS OF A GROUP WITH THE SAME PRIME GRAPH AS Ln(5)",
journal="Journal of Algebraic Systems",
year="2016",
volume="4",
number="1",
pages="37-51",
abstract="The prime graph of a finite group $G$ is denoted by$ga(G)$. A nonabelian simple group $G$ is called quasirecognizable by primegraph, if for every finite group $H$, where $ga(H)=ga(G)$, thereexists a nonabelian composition factor of $H$ which is isomorphic to$G$. Until now, it is proved that some finite linear simple groups arequasirecognizable by prime graph, for instance, the linear groups $L_n(2)$ and $L_n(3)$ are quasirecognizable by prime graph. In this paper, we consider thequasirecognition by prime graph of the simple group $L_n(5)$.",
issn="2345-5128",
doi="10.22044/jas.2016.727",
url="http://jas.shahroodut.ac.ir/article_727.html"
}
@Article{Safaeeyan2016,
author="Safaeeyan, S.",
title="STRONGLY DUO AND CO-MULTIPLICATION MODULES",
journal="Journal of Algebraic Systems",
year="2016",
volume="4",
number="1",
pages="53-64",
abstract="Let R be a commutative ring. An R-module M is called co-multiplication provided that foreach submodule N of M there exists an ideal I of R such that N = (0 : I). In this paper weshow that co-multiplication modules are a generalization of strongly duo modules. Uniserialmodules of finite length and hence valuation Artinian rings are some distinguished classes ofco-multiplication rings. In addition, if R is a Noetherian ring, then R is a strongly duoring if and only if R is a co-multiplication ring. We also show that J-semisimple strongly duorings are precisely semisimple rings. Moreover, if R is a perfect ring, then uniserial R-modules are co-multiplication of finite length modules. Finally, we showthat Abelian co-multiplication groups are reduced and co-multiplication Z-modules(Abeliangroups)are characterized.",
issn="2345-5128",
doi="10.22044/jas.2016.728",
url="http://jas.shahroodut.ac.ir/article_728.html"
}
@Article{Behtoei2016,
author="Behtoei, A.
and Vatandoost, E.
and Azizi Rajol Abad, F.",
title="SIGNED ROMAN DOMINATION NUMBER AND JOIN OF GRAPHS",
journal="Journal of Algebraic Systems",
year="2016",
volume="4",
number="1",
pages="65-77",
abstract="In this paper we study the signed Roman dominationnumber of the join of graphs. Specially, we determine it for thejoin of cycles, wheels, fans and friendship graphs.",
issn="2345-5128",
doi="10.22044/jas.2016.729",
url="http://jas.shahroodut.ac.ir/article_729.html"
}
@Article{Saremi2016,
author="Saremi, H.",
title="ARTINIANNESS OF COMPOSED LOCAL COHOMOLOGY MODULES",
journal="Journal of Algebraic Systems",
year="2016",
volume="4",
number="1",
pages="79-84",
abstract="Let $R$ be a commutative Noetherian ring and let $fa$, $fb$ be two ideals of $R$ such that $R/({fa+fb})$ is Artinian. Let $M$, $N$ be two finitely generated $R$-modules. We prove that $H_{fb}^j(H_{fa}^t(M,N))$ is Artinian for $j=0,1$, where $t=inf{iin{mathbb{N}_0}: H_{fa}^i(M,N)$ is not finitelygenerated $}$. Also, we prove that if $DimSupp(H_{fa}^i(M,N))leq 2$, then $H_{fb}^1(H_{fa}^i(M,N))$ is Artinian for all $i$. Moreover, we show that if $dim N=d$, then $H_{fb}^j(H_{fa}^{d-1}(N))$ is Artinian for all $jgeq 1$.",
issn="2345-5128",
doi="10.22044/jas.2016.730",
url="http://jas.shahroodut.ac.ir/article_730.html"
}