2018-01-19T18:36:25Z
http://bims.iranjournals.ir/?_action=export&rf=summon&issue=51
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
Topological centers of the n-th dual of module actions
K.
Haghnejad Azar
A.
Riazi
We study the topological centers of $nth$ dual of Banach $mathcal{A}$-modules and we extend some propositions from Lau and "{U}lger into $n-th$ dual of Banach $mathcal{A}-modules$ where $ngeq 0$ is even number. Let $mathcal{B}$ be a Banach $mathcal{A}-bimodule$. By using some new conditions, we show that $ Z^ell_{mathcal{A}^{(n)}}(mathcal{B}^{(n)})=mathcal{B}^{(n)}$ and $ Z^ell_{mathcal{B}^{(n)}}(mathcal{A}^{(n)})=mathcal{A}^{(n)}$. We get some conclusions on group algebras.
Arens regularity
bilinear mapping
topological
center
2012
04
01
1
16
http://bims.iranjournals.ir/article_387_cd1a28bd46a6adf2fd6bf0a3fd1322c3.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
Lie triple derivation algebra of Virasoro-like algebra
H.
Wang
N.
Jing
Q. G.
Li
Let $mathfrak{L}$ be the Virasoro-like algebra and $mathfrak{g}$ itsderived algebra, respectively. We investigate the structure of the Lie triplederivation algebra of $mathfrak{L}$ and $mathfrak{g}$. We provethat they are both isomorphic to $mathfrak{L}$, which provides twoexamples of invariance under triple derivation.
Lie derivation
Lie triple derivation
Virasoro-like algebra
2012
04
01
17
26
http://bims.iranjournals.ir/article_388_4ddeb63a9ac76b95a5711ce7787b4f74.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
Function spaces of Rees matrix semigroups
H.
Rahimi
We characterize function spaces of Rees matrixsemigroups. Then we study these spaces by using the topologicaltensor product technique.
Semigroup compactification
completely 0-simple
semigroup
topological tensor product
2012
04
01
27
38
http://bims.iranjournals.ir/article_389_a776904facf379b7bc84321bd942fa54.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
Construction of a class of trivariate nonseparable compactly
supported wavelets with special dilation matrix
L.
Lan
C.
Zhengxing
H.
Yongdong
We present a method for the construction of compactlysupported $left (begin{array}{lll}1 & 0 & -1\1 & 1 & 0 \1 & 0 & 1\end{array}right )$-wavelets under a mild condition. Wavelets inherit thesymmetry of the corresponding scaling function and satisfies thevanishing moment condition originating in the symbols of the scalingfunction. As an application, an example is provided.
2012
04
01
39
54
http://bims.iranjournals.ir/article_390_5971fe402882bf91ce2224f6141594a0.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
On skew Armendariz and skew quasi-Armendariz
modules
A.
Alhevaz
A.
Moussavi
Let $alpha$ be an endomorphism and $delta$ an $alpha$-derivationof a ring $R$. In this paper we study the relationship between an$R$-module $M_R$ and the general polynomial module $M[x]$ over theskew polynomial ring $R[x;alpha,delta]$. We introduce the notionsof skew-Armendariz modules and skew quasi-Armendariz modules whichare generalizations of $alpha$-Armendariz modules and extend theclasses of non-reduced skew-Armendariz modules. An equivalentcharacterization of an $alpha$-skew Armendariz module is given.Some properties of this generalization are established, andconnections of properties of a skew-Armendariz module $M_R$ withthose of $M[x]_{R[x;alpha,delta]}$ are investigated. As aconsequence we extend and unify several known results related toArmendariz modules.
2012
04
01
55
84
http://bims.iranjournals.ir/article_391_faa8203cae36d2ab955dfe7cff11023e.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
Compact composition operators on certain analytic Lipschitz spaces
H.
Mahyar
A.
Sanatpour
We investigate compact composition operators on ceratin Lipschitzspaces of analytic functions on the closed unit disc of the plane.Our approach also leads to some results about compositionoperators on Zygmund type spaces.
Compact operators
Bloch type spaces
Zygmund type
spaces
analytic Lipschitz spaces
differentiable Lipschitz
spaces
2012
04
01
85
99
http://bims.iranjournals.ir/article_392_68613fe870e50c12191861e98cadfcf1.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
On a decomposition of Hardy--Hilbert's type inequality
R.
Lashkaripour
A.
Moazzen
In this paper, two pairs of new inequalities are given, which decompose two Hilbert-type inequalities.
Hilbert's inequality
Hilbert-type inequality
integral inequality
2012
04
01
101
112
http://bims.iranjournals.ir/article_393_590b376cd7b26b3fc6a94b9b95691cb4.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
On co-Noetherian dimension of rings
A.
Haghany
M.
Vedadi
We define and studyco-Noetherian dimension of rings for which the injective envelopeof simple modules have finite Krull-dimension. This is a Moritainvariant dimension that measures how far the ring is from beingco-Noetherian. The co-Noetherian dimension of certain rings,including commutative rings, are determined. It is shown that the class ${mathcal W}_n$ of rings with co-Noetherian dimension $leqn$ is closed under homomorphic images and finite normalizingextensions, and that for each $n$ there exist rings withco-Noetherian dimension $n$. The possible relations between Krull and co-Noetherian dimensions are investigated, and examples are provided to show that these dimensions are independent of eachother.
Co-Noetherian
finitely cogenerated
Krull dimension
normalizing extension
2012
04
01
113
122
http://bims.iranjournals.ir/article_394_22246e6a6d66013fdfd1ed4b2e6cbbf3.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
On topological transitive maps on operator algebras
H.
Rezaei
We consider the transitive linear maps on the operator algebra $B(X)$for a separable Banach space $X$. We show if a bounded linear map is norm transitive on $B(X)$,then it must be hypercyclic with strong operator topology. Also we provide a SOT-transitivelinear map without being hypercyclic in the strong operator topology.
Hypercyclic operator
transitive map
strong operator topology
2012
04
01
123
130
http://bims.iranjournals.ir/article_395_7f397c884503a656306bf029f5887d11.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
Ranks of the common solution to some quaternion matrix equations
with applications
Q.
Wang
S.
Yu
We derive the formulas of the maximal andminimal ranks of four real matrices $X_{1},X_{2},X_{3}$ and $X_{4}$in common solution $X=X_{1}+X_{2}i+X_{3}j+X_{4}k$ to quaternionmatrix equations $A_{1}X=C_{1},XB_{2}=C_{2},A_{3}XB_{3}=C_{3}$. Asapplications, we establish necessary and sufficient conditions forthe existence of the common real and complex solutions to the matrixequations. We give the expressions of such solutions to this systemwhen the solvability conditions are met. Moreover, we presentnecessary and sufficient conditions for the existence of real andcomplex solutions to the system of quaternionmatrix equations $A_{1}X=C_{1},XB_{2}=C_{2},A_{3}XB_{3}=C_{3},A_{4}%XB_{4}=C_{4}$. The findings of this paper extend some known resultsin the literature.
Quaternion matrix equation
maximal and minimal rank
generalized inverse
real solution
complex solution
2012
04
01
131
157
http://bims.iranjournals.ir/article_396_b3c2a4e18ed3cb578254fb893db94ade.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
On Heyting algebras and dual BCK-algebras
Y.
Yon
K.
Kim
A Heyting algebra is a distributive lattice with implication and a dual $BCK$-algebra is an algebraic system having as models logical systems equipped with implication. The aim of this paper is to investigate the relation of Heyting algebras between dual $BCK$-algebras. We define notions of $i$-invariant and $m$-invariant on dual $BCK$-semilattices and prove that a Heyting semilattice is equivalent to an $i$-invariant and $m$-invariant dual $BCK$-semilattices, and show that a commutative Heyting algebra is equivalent to a bounded implicative dual $BCK$-algebra.
Heyting semilattice
Heyting algebra
dual $BCK$-algebra
2012
04
01
159
168
http://bims.iranjournals.ir/article_397_0b7c6a289b3214ec9be3fec521a61f1a.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
Application of fundamental relations on n-ary polygroups
S.
Mirvakili
B.
Davvaz
The class of $n$-ary polygroups is a certain subclass of $n$-ary hypergroups, a generalization of D{"o}rnte $n$-arygroups and a generalization of polygroups. The$beta^*$-relation and the $gamma^*$-relation are the smallestequivalence relations on an $n$-ary polygroup $P$ such that$P/beta^*$ and $P/gamma^*$ are an $n$-ary group and acommutative $n$-ary group, respectively. We use the $beta^*$-relation and the $gamma^*$-relation on a given$n$-ary polygroup and obtain some new results and somefundamental theorems in this respect. In particular, we prove that the relation $gamma$ is transitive on an $n$-arypolygroup.
Hypergroup
polygroup
$n$-ary
hypergroup
$n$-ary polygroup
derived $n$-ary subgroup
fundamental relation
2012
04
01
169
184
http://bims.iranjournals.ir/article_398_343a6bc9bb99db6c78480f38fbc278d8.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
Bivariate mean value interpolation on circles of the same radius
Kh.
Rahsepar Fard
We consider bivariate mean-value interpolationproblem, where the integrals over circles are interpolation data. In this case the problem is described over circles of the same radius and with centers are on astraight line and it is shown that in this case the interpolation is not correct.
Bivariate
correct
mean-value interpolation
2012
04
01
185
192
http://bims.iranjournals.ir/article_399_b95dcaa7d9bc7d748d78d1b8e2d96805.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
k-forested choosability of graphs with bounded maximum average degree
X.
Zhang
G.
Liu
J.
Wu
A proper vertex coloring of a simple graph is $k$-forested if the graph induced by the vertices of any two color classes is a forest with maximum degree less than $k$. A graph is $k$-forested $q$-choosable if for a given list of $q$ colors associated with each vertex $v$, there exists a $k$-forested coloring of $G$ such that each vertex receives a color from its own list. In this paper, we prove that the $k$-forested choosability of a graph with maximum degree $Deltageq kgeq 4$ is at most $leftlceilfrac{Delta}{k-1}rightrceil+1$, $leftlceilfrac{Delta}{k-1}rightrceil+2$ or $leftlceilfrac{Delta}{k-1}rightrceil+3$ if its maximum average degree is less than $frac{12}{5}$, $frac{8}{3}$ or $3$, respectively.
k-forested coloring
linear coloring
maximum average degree
2012
04
01
193
201
http://bims.iranjournals.ir/article_400_33c983c4321f08451943d77a341f126b.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
c-Frames and c-Bessel mappings
M.
Faroughi
E.
Osgooei
The theory of c-frames and c-Bessel mappings are the generalizationsof the theory of frames and Bessel sequences. In this paper, weobtain several equivalent conditions for dual of c-Bessel mappings.We show that for a c-Bessel mapping $f$, a retrievalformula with respect to a c-Bessel mapping $g$ is satisfied if andonly if $g$ is sum of the canonical dual of $f$ with a c-Besselmapping which weakly belongs to the null space of the pre-frame operatorof $f$. Also, we prove that composition of pre-frame operator withanalysis operator of two square norm integrable c-Bessel mappingsare trace class operators.
Lebesque integral
Hilbert space
C*-algebra
trace class operator
frame theory
2012
04
01
203
222
http://bims.iranjournals.ir/article_401_8c30c121871d0918061a85cbc216a1ae.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
A variational approach to the problem of oscillations of an
elastic half cylinder
M.
Hasansoy
This paper is devoted to the spectral theory (more precisely, tothe variational theory of the spectrum) of guided waves in anelastic half cylinder. We use variational methods to investigateseveral aspects of propagating waves, including localization (seeFigure 1), existence criteria and the formulas to find them. Weapproach the problem using two complementary methods: Thevariational methods for non-overdamped operator pencils todescribe eigenvalues in definite spectral zones, andLjusternik-Schnirelman critical point theory to investigateeigenvalues in the mixed spectral zone where the classicalvariational theory of operator pencils is not applicable.
Propagating waves
Eigenvalue
variational principle
critical point
2012
04
01
223
240
http://bims.iranjournals.ir/article_402_a5aba3e401d0e7ee3449edaa65081a67.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
On the existence and uniqueness of solution of initial value problem for fractional order differential equations on time scales
A.
Ahmadkhanlu
M.
Jahanshahi
n this paper, at first the concept of Caputo fractionalderivative is generalized on time scales. Then the fractional orderdifferential equations are introduced on time scales. Finally,sufficient and necessary conditions are presented for the existenceand uniqueness of solution of initial valueproblem including fractional order differential equations.
Time scales
differential equations
initial value problem
fractional order derivative
2012
01
01
241
252
http://bims.iranjournals.ir/article_403_01350f088186d1293a225495267a033a.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
On the stability of generalized derivations on Banach algebras
E.
Ansari-Piri
E.
Anjidani
We investigate the stability of generalizedderivations on Banach algebras with a bounded central approximateidentity. We show that every approximate generalized derivation inthe sense of Rassias, is an exact generalized derivation. Also thestability problem of generalized derivations on the faithful Banachalgebras is investigated.
Hyers-Ulam-Rassias stability
generalized
derivation
bounded central approximate identity
faithful Banach
algebra
2012
04
01
253
263
http://bims.iranjournals.ir/article_404_995234a601e9852e2877afdf4d4a996d.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
Non-regularity of multiplications for general measure algebras
J.
Laali
M.
Ettefagh
Let $fM(X)$ be the space of all finite regular Borel measures on $X$. A general measure algebra is a subspace of$fM(X)$,which is an $L$-space and has a multiplication preserving the probability measures. Let $cLsubseteqfM(X)$ be a general measure algebra on a locallycompact space $X$. In this paper, we investigate the relation between Arensregularity of $cL$ and the topology of $X$. We find conditionsunder which the Arens regularity of $fL$ implies the compactness of $X$.Weshow that these conditions are necessary.We also present some examples in showing that the new conditions aredifferent from Theorem 3.1 of cite{7}.
2012
04
01
265
274
http://bims.iranjournals.ir/article_405_227f292f58bd40a514de4597f4abbad2.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2012
38
1
Extensions of strongly alpha-reversible rings
L.
Zhao
X.
Zhu
We introduce the notion ofstrongly $alpha$-reversible rings which is a strong version of$alpha$-reversible rings, and investigate its properties. We firstgive an example to show that strongly reversible rings need not bestrongly $alpha$-reversible. We next argue about the strong$alpha$-reversibility of some kinds of extensions. A number ofproperties of this version are established. It is shown that a ring$R$ is strongly right $alpha$-reversible if and only if itspolynomial ring $R[x]$ is strongly right $alpha$-reversible if andonly if its Laurent polynomial ring $R[x, x^{-1}]$ is strongly right$alpha$-reversible. Moreover, we introduce the concept ofNil-$alpha$-reversible rings to investigate the nilpotent elementsin $alpha$-reversible rings. Examples are given to show that rightNil-$alpha$-reversible rings need not be right $alpha$-reversible.
reversible rings
strongly $alpha$-reversible rings
Nil-$alpha$-reversible rings
weakly reversible rings
2012
04
01
275
292
http://bims.iranjournals.ir/article_406_9c2daebbe954621c0aa88d44f49c476e.pdf