ORIGINAL_ARTICLE
Topological centers of the n-th dual of module actions
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.
http://bims.iranjournals.ir/article_387_cd1a28bd46a6adf2fd6bf0a3fd1322c3.pdf
2012-04-01
1
16
Arens regularity
bilinear mapping
topological
center
K.
Haghnejad Azar
1
University of Mohghegh Ardabili
LEAD_AUTHOR
A.
Riazi
2
Amirkabir University of Technology
AUTHOR
ORIGINAL_ARTICLE
Lie triple derivation algebra of Virasoro-like algebra
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.
http://bims.iranjournals.ir/article_388_4ddeb63a9ac76b95a5711ce7787b4f74.pdf
2012-04-01
17
26
Lie derivation
Lie triple derivation
Virasoro-like algebra
H.
Wang
1
Hunan University, China
AUTHOR
N.
Jing
2
South China University of Technology, China
LEAD_AUTHOR
Q. G.
Li
3
Hunan University, China
AUTHOR
ORIGINAL_ARTICLE
Function spaces of Rees matrix semigroups
We characterize function spaces of Rees matrixsemigroups. Then we study these spaces by using the topologicaltensor product technique.
http://bims.iranjournals.ir/article_389_a776904facf379b7bc84321bd942fa54.pdf
2012-04-01
27
38
Semigroup compactification
completely 0-simple
semigroup
topological tensor product
H.
Rahimi
rahimi@iauctb.ac.ir
1
Islamic Azad University, Iran
LEAD_AUTHOR
ORIGINAL_ARTICLE
Construction of a class of trivariate nonseparable compactly
supported wavelets with special dilation matrix
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.
http://bims.iranjournals.ir/article_390_5971fe402882bf91ce2224f6141594a0.pdf
2012-04-01
39
54
L.
Lan
1
Xi'an University of Arts and Science
LEAD_AUTHOR
C.
Zhengxing
2
Xi'an Jiaotong University
AUTHOR
H.
Yongdong
3
The Northwest Secondly National College
AUTHOR
ORIGINAL_ARTICLE
On skew Armendariz and skew quasi-Armendariz
modules
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.
http://bims.iranjournals.ir/article_391_faa8203cae36d2ab955dfe7cff11023e.pdf
2012-04-01
55
84
A.
Alhevaz
a.alhevaz@yahoo.com
1
Tarbiat Modares University
AUTHOR
A.
Moussavi
moussavi.a@modares.ac.ir
2
Tarbiat Modares University
LEAD_AUTHOR
ORIGINAL_ARTICLE
Compact composition operators on certain analytic Lipschitz spaces
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.
http://bims.iranjournals.ir/article_392_68613fe870e50c12191861e98cadfcf1.pdf
2012-04-01
85
99
Compact operators
Bloch type spaces
Zygmund type
spaces
analytic Lipschitz spaces
differentiable Lipschitz
spaces
H.
Mahyar
1
Kharazmi University
LEAD_AUTHOR
A.
Sanatpour
2
Kharazmi University
AUTHOR
ORIGINAL_ARTICLE
On a decomposition of Hardy--Hilbert's type inequality
In this paper, two pairs of new inequalities are given, which decompose two Hilbert-type inequalities.
http://bims.iranjournals.ir/article_393_590b376cd7b26b3fc6a94b9b95691cb4.pdf
2012-04-01
101
112
Hilbert's inequality
Hilbert-type inequality
integral inequality
R.
Lashkaripour
1
University of Sistan and Baluchestan
LEAD_AUTHOR
A.
Moazzen
2
University of Sistan and Baluchestan
AUTHOR
ORIGINAL_ARTICLE
On co-Noetherian dimension of rings
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.
http://bims.iranjournals.ir/article_394_22246e6a6d66013fdfd1ed4b2e6cbbf3.pdf
2012-04-01
113
122
Co-Noetherian
finitely cogenerated
Krull dimension
normalizing extension
A.
Haghany
aghagh@cc.iut.ac.ir
1
Isfahan University of Technology
AUTHOR
M.
Vedadi
mrvedadi@cc.iut.ac.ir
2
Isfahan University of Technology
LEAD_AUTHOR
ORIGINAL_ARTICLE
On topological transitive maps on operator algebras
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.
http://bims.iranjournals.ir/article_395_7f397c884503a656306bf029f5887d11.pdf
2012-04-01
123
130
Hypercyclic operator
transitive map
strong operator topology
H.
Rezaei
rezaei@mail.yu.ac.ir
1
University of Yasouj
LEAD_AUTHOR
ORIGINAL_ARTICLE
Ranks of the common solution to some quaternion matrix equations
with applications
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 for\the 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.
http://bims.iranjournals.ir/article_396_b3c2a4e18ed3cb578254fb893db94ade.pdf
2012-04-01
131
157
Quaternion matrix equation
maximal and minimal rank
generalized inverse
real solution
complex solution
Q.
Wang
wqw858@yahoo.com.cn
1
Shanghai University
AUTHOR
S.
Yu
yushawn@163.com
2
East China University of Science and Technology
LEAD_AUTHOR
ORIGINAL_ARTICLE
On Heyting algebras and dual BCK-algebras
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.
http://bims.iranjournals.ir/article_397_0b7c6a289b3214ec9be3fec521a61f1a.pdf
2012-04-01
159
168
Heyting semilattice
Heyting algebra
dual $BCK$-algebra
Y.
Yon
yhyon@mokwon.ac.kr
1
Mokwon University
AUTHOR
K.
Kim
ghkim@cjnu.ac.kr
2
Chungju National University
LEAD_AUTHOR
ORIGINAL_ARTICLE
Application of fundamental relations on n-ary polygroups
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.
http://bims.iranjournals.ir/article_398_343a6bc9bb99db6c78480f38fbc278d8.pdf
2012-04-01
169
184
Hypergroup
polygroup
$n$-ary
hypergroup
$n$-ary polygroup
derived $n$-ary subgroup
fundamental relation
S.
Mirvakili
saeed mirvakili@yahoo.com
1
Payame Noor University
AUTHOR
B.
Davvaz
davvaz@yazduni.ac.ir
2
Yazd University
LEAD_AUTHOR
ORIGINAL_ARTICLE
Bivariate mean value interpolation on circles of the same radius
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.
http://bims.iranjournals.ir/article_399_b95dcaa7d9bc7d748d78d1b8e2d96805.pdf
2012-04-01
185
192
Bivariate
correct
mean-value interpolation
Kh.
Rahsepar Fard
rahseparfard@gmail.com
1
University of Qom
LEAD_AUTHOR
ORIGINAL_ARTICLE
k-forested choosability of graphs with bounded maximum average degree
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 $\Delta\geq k\geq 4$ is at most $\left\lceil\frac{\Delta}{k-1}\right\rceil+1$, $\left\lceil\frac{\Delta}{k-1}\right\rceil+2$ or $\left\lceil\frac{\Delta}{k-1}\right\rceil+3$ if its maximum average degree is less than $\frac{12}{5}$, $\frac{8}{3}$ or $3$, respectively.
http://bims.iranjournals.ir/article_400_33c983c4321f08451943d77a341f126b.pdf
2012-04-01
193
201
k-forested coloring
linear coloring
maximum average degree
X.
Zhang
xzhang@xidian.edu.cn
1
Xidian University
AUTHOR
G.
Liu
gzliu@sdu.edu.cn
2
Shandong University
LEAD_AUTHOR
J.
Wu
jlwu@sdu.edu.cn
3
Shandong University
AUTHOR
ORIGINAL_ARTICLE
c-Frames and c-Bessel mappings
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.
http://bims.iranjournals.ir/article_401_8c30c121871d0918061a85cbc216a1ae.pdf
2012-04-01
203
222
Lebesque integral
Hilbert space
C*-algebra
trace class operator
frame theory
M.
Faroughi
mhfaroughi@yahoo.com
1
Islamic Azad University
LEAD_AUTHOR
E.
Osgooei
Oskouei@yahoo.com
2
University of Tabriz
AUTHOR
ORIGINAL_ARTICLE
A variational approach to the problem of oscillations of an
elastic half cylinder
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.
http://bims.iranjournals.ir/article_402_a5aba3e401d0e7ee3449edaa65081a67.pdf
2012-04-01
223
240
Propagating waves
Eigenvalue
variational principle
critical point
M.
Hasansoy
mhasansoy@dogus.edu.tr
1
Dogus University
LEAD_AUTHOR
ORIGINAL_ARTICLE
On the existence and uniqueness of solution of initial value problem for fractional order differential equations on time scales
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.
http://bims.iranjournals.ir/article_403_01350f088186d1293a225495267a033a.pdf
2012-01-01
241
252
Time scales
differential equations
initial value problem
fractional order derivative
A.
Ahmadkhanlu
s.a.ahmadkhanlu@azaruniv.edu
1
Azarbayjan University of Tarbiat Moallem
AUTHOR
M.
Jahanshahi
jahanshahi@azaruniv.edu
2
Azarbayjan University of Tarbiat Moallem
LEAD_AUTHOR
ORIGINAL_ARTICLE
On the stability of generalized derivations on Banach algebras
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.
http://bims.iranjournals.ir/article_404_995234a601e9852e2877afdf4d4a996d.pdf
2012-04-01
253
263
Hyers-Ulam-Rassias stability
generalized
derivation
bounded central approximate identity
faithful Banach
algebra
E.
Ansari-Piri
e−ansari@guilan.ac.ir
1
University of Guilan
LEAD_AUTHOR
E.
Anjidani
ehsan−anjidani@guilan.ac.ir
2
University of Guilan
AUTHOR
ORIGINAL_ARTICLE
Non-regularity of multiplications for general measure algebras
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}.
http://bims.iranjournals.ir/article_405_227f292f58bd40a514de4597f4abbad2.pdf
2012-04-01
265
274
J.
Laali
Laali@tmu.ac.ir
1
Kharazmi University
LEAD_AUTHOR
M.
Ettefagh
etefagh@iaut.ac.ir
2
Islamic Azad University
AUTHOR
ORIGINAL_ARTICLE
Extensions of strongly \alpha-reversible rings
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.
http://bims.iranjournals.ir/article_406_9c2daebbe954621c0aa88d44f49c476e.pdf
2012-04-01
275
292
reversible rings
strongly $\alpha$-reversible rings
Nil-$\alpha$-reversible rings
weakly reversible rings
L.
Zhao
lzhao78@gmail.com
1
Nanjing University
AUTHOR
X.
Zhu
zhuxs@nju.edu.cn
2
Nanjing University
LEAD_AUTHOR