Volume 42, Issue 2
مرور بر اساس
ارسال های اخیر
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Examples of non-quasicommutative semigroups decomposed into unions of groups
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)Decomposability of an algebraic structure into the union of its sub-structures goes back to G. Scorza's Theorem of 1926 for groups. An analogue of this theorem for rings has been recently studied by A. Lucchini in 2012. ...
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Pseudo Ricci symmetric real hypersurfaces of a complex projective space
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)Pseudo Ricci symmetric real hypersurfaces of a complex projective space are classified and it is proved that there are no pseudo Ricci symmetric real hypersurfaces of the complex projective space CPn for which the vector ...
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On linear preservers of sgut-majorization on $textbf{M}_{n,m}$
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)Let $textbf{M}_{n,m}$ be the set of $n$-by-$m$ matrices with entries in the field of real numbers. A matrix $R$ in $textbf{M}_{n}=textbf{M}_{n,n}$ is a generalized row substochastic matrix (g-row substochastic, for ...
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The augmented Zagreb index, vertex connectivity and matching number of graphs
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)Let $Gamma_{n,kappa}$ be the class of all graphs with $ngeq3$ vertices and $kappageq2$ vertex connectivity. Denote by $Upsilon_{n,beta}$ the family of all connected graphs with $ngeq4$ vertices and matching number $beta$ ...
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Existence of ground states for approximately inner two--parameter $C_0$--groups on $C^*$--algebras
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)In this paper, we generalize the definitions of approximately inner $C_0$-groups and their ground states to the two- parameter case and study necessary and sufficient conditions for a state to be ground state. Also we prove ...
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On cycles in intersection graphs of rings
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)Let $R$ be a commutative ring with non-zero identity. We describe all $C_3$- and $C_4$-free intersection graph of non-trivial ideals of $R$ as well as $C_n$-free intersection graph when $R$ is a reduced ring. Also, ...
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The unit sum number of Baer rings
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)In this paper we prove that each element of any regular Baer ring is a sum of two units if no factor ring of $R$ is isomorphic to $Z_2$ and we characterize regular Baer rings with unit sum numbers $omega$ and $infty$. ...
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Remarks on microperiodic multifunctions
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)It is well known that a microperiodic function mapping a topological group into reals, which is continuous at some point is constant. We introduce the notion of a microperiodic multifunction, defined on a topological group ...
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Finite groups with $X$-quasipermutable subgroups of prime power order
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)Let $H$, $L$ and $X$ be subgroups of a finite group $G$. Then $H$ is said to be $X$-permutable with $L$ if for some$xin X$ we have $AL^{x}=L^{x}A$. We say that $H$ is emph{$X$-quasipermutable } (emph{$X_{S}$-quasi ...
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Partial proof of Graham Higman's conjecture related to coset diagrams
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)Graham Higman has defined coset diagrams for PSL(2,ℤ). These diagrams are composed of fragments, and the fragments are further composed of two or more circuits. Q. Mushtaq has proved in 1983 that existence of a certain ...
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Every class of $S$-acts having a flatness property is closed under directed colimits
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)Let $S$ be a monoid. In this paper, we prove every class of $S$-acts having a flatness property is closed underdirected colimits, it extends some known results. Furthermore this result implies that every $S$-act has a ...
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On Silverman's conjecture for a family of elliptic curves
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)Let $E$ be an elliptic curve over $Bbb{Q}$ with the given Weierstrass equation $ y^2=x^3+ax+b$. If $D$ is a squarefree integer, then let $E^{(D)}$ denote the $D$-quadratic twist of $E$ that is given by $E^{(D)}: ...
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Toroidalization of locally toroidal morphisms of 3-folds
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)A toroidalization of a dominant morphism $varphi: Xto Y$ of algebraic varieties over a field of characteristic zero is a toroidal lifting of $varphi$ obtained by performing sequences of blow ups of nonsingular subvarieties ...
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Locally GCD domains and the ring $D+XD_S[X]$
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)An integral domain $D$ is called a emph{locally GCD domain} if $D_{M}$ is a GCD domain for every maximal ideal $M$ of $D$. We study some ring-theoretic properties of locally GCD domains. E.g., we show that $D$ is a locally ...
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A new approach for solving the first-order linear matrix differential equations
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)Abstract. The main contribution of the current paper is to propose a new effective numerical method for solving the first-order linear matrix differential equations. Properties of the Legendre basis operational matrix of ...
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Sufficiency and duality for a nonsmooth vector optimization problem with generalized $alpha$-$d_{I}$-type-I univexity over cones
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)In this paper, using Clarke's generalized directional derivative and dI-invexity we introduce new concepts of nonsmooth K-α-dI-invex and generalized type I univex functions over cones for a nonsmooth vector optimization ...
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An analytic solution for a non-local initial-boundary value problem including a partial differential equation with variable coefficients
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)This paper considers a non-local initial-boundary value problem containing a first order partial differential equation with variable coefficients. At first, the non-self-adjoint spectral problem is derived. Then its ...
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Trivially related lax pairs of the Sawada-Kotera equation
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)We show that a recently introduced Lax pair of the Sawada-Kotera equation is not a new one but is trivially related to the known old Lax pair. Using the so-called trivial compositions of the old Lax pairs with a differentially ...
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Existence of solutions of boundary value problems for Caputo fractional differential equations on time scales
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)In this paper, we study the boundary-value problem of fractional order dynamic equations on time scales, $$ ^c{Delta}^{alpha}u(t)=f(t,u(t)),;;tin [0,1]_{mathbb{T}^{kappa^{2}}}:=J,;;1
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Bulletin of the Iranian Mathematical Society
(Springer and the Iranian Mathematical Society (IMS), 2016-04-01)
