eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
1
16
387
Topological centers of the n-th dual of module actions
K. Haghnejad Azar
1
A. Riazi
2
University of Mohghegh Ardabili
Amirkabir University of Technology
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
Arens regularity
bilinear mapping
topological
center
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
17
26
388
Lie triple derivation algebra of Virasoro-like algebra
H. Wang
1
N. Jing
2
Q. G. Li
3
Hunan University, China
South China University of Technology, China
Hunan University, China
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
Lie derivation
Lie triple derivation
Virasoro-like algebra
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
27
38
389
Function spaces of Rees matrix semigroups
H. Rahimi
rahimi@iauctb.ac.ir
1
Islamic Azad University, Iran
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
Semigroup compactification
completely 0-simple
semigroup
topological tensor product
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
39
54
390
Construction of a class of trivariate nonseparable compactly
supported wavelets with special dilation matrix
L. Lan
1
C. Zhengxing
2
H. Yongdong
3
Xi'an University of Arts and Science
Xi'an Jiaotong University
The Northwest Secondly National College
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
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
55
84
391
On skew Armendariz and skew quasi-Armendariz
modules
A. Alhevaz
a.alhevaz@yahoo.com
1
A. Moussavi
moussavi.a@modares.ac.ir
2
Tarbiat Modares University
Tarbiat Modares University
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
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
85
99
392
Compact composition operators on certain analytic Lipschitz spaces
H. Mahyar
1
A. Sanatpour
2
Kharazmi University
Kharazmi University
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
Compact operators
Bloch type spaces
Zygmund type
spaces
analytic Lipschitz spaces
differentiable Lipschitz
spaces
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
101
112
393
On a decomposition of Hardy--Hilbert's type inequality
R. Lashkaripour
1
A. Moazzen
2
University of Sistan and Baluchestan
University of Sistan and Baluchestan
In this paper, two pairs of new inequalities are given, which decompose two Hilbert-type inequalities.
http://bims.iranjournals.ir/article_393_590b376cd7b26b3fc6a94b9b95691cb4.pdf
Hilbert's inequality
Hilbert-type inequality
integral inequality
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
113
122
394
On co-Noetherian dimension of rings
A. Haghany
aghagh@cc.iut.ac.ir
1
M. Vedadi
mrvedadi@cc.iut.ac.ir
2
Isfahan University of Technology
Isfahan University of Technology
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
Co-Noetherian
finitely cogenerated
Krull dimension
normalizing extension
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
123
130
395
On topological transitive maps on operator algebras
H. Rezaei
rezaei@mail.yu.ac.ir
1
University of Yasouj
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
Hypercyclic operator
transitive map
strong operator topology
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
131
157
396
Ranks of the common solution to some quaternion matrix equations
with applications
Q. Wang
wqw858@yahoo.com.cn
1
S. Yu
yushawn@163.com
2
Shanghai University
East China University of Science and Technology
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.
http://bims.iranjournals.ir/article_396_b3c2a4e18ed3cb578254fb893db94ade.pdf
Quaternion matrix equation
maximal and minimal rank
generalized inverse
real solution
complex solution
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
159
168
397
On Heyting algebras and dual BCK-algebras
Y. Yon
yhyon@mokwon.ac.kr
1
K. Kim
ghkim@cjnu.ac.kr
2
Mokwon University
Chungju National University
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
Heyting semilattice
Heyting algebra
dual $BCK$-algebra
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
169
184
398
Application of fundamental relations on n-ary polygroups
S. Mirvakili
saeed mirvakili@yahoo.com
1
B. Davvaz
davvaz@yazduni.ac.ir
2
Payame Noor University
Yazd University
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
Hypergroup
polygroup
$n$-ary
hypergroup
$n$-ary polygroup
derived $n$-ary subgroup
fundamental relation
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
185
192
399
Bivariate mean value interpolation on circles of the same radius
Kh. Rahsepar Fard
rahseparfard@gmail.com
1
University of Qom
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
Bivariate
correct
mean-value interpolation
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
193
201
400
k-forested choosability of graphs with bounded maximum average degree
X. Zhang
xzhang@xidian.edu.cn
1
G. Liu
gzliu@sdu.edu.cn
2
J. Wu
jlwu@sdu.edu.cn
3
Xidian University
Shandong University
Shandong University
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.
http://bims.iranjournals.ir/article_400_33c983c4321f08451943d77a341f126b.pdf
k-forested coloring
linear coloring
maximum average degree
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
203
222
401
c-Frames and c-Bessel mappings
M. Faroughi
mhfaroughi@yahoo.com
1
E. Osgooei
Oskouei@yahoo.com
2
Islamic Azad University
University of Tabriz
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
Lebesque integral
Hilbert space
C*-algebra
trace class operator
frame theory
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
223
240
402
A variational approach to the problem of oscillations of an
elastic half cylinder
M. Hasansoy
mhasansoy@dogus.edu.tr
1
Dogus University
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
Propagating waves
Eigenvalue
variational principle
critical point
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-01-01
38
1
241
252
403
On the existence and uniqueness of solution of initial value problem for fractional order differential equations on time scales
A. Ahmadkhanlu
s.a.ahmadkhanlu@azaruniv.edu
1
M. Jahanshahi
jahanshahi@azaruniv.edu
2
Azarbayjan University of Tarbiat Moallem
Azarbayjan University of Tarbiat Moallem
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
Time scales
differential equations
initial value problem
fractional order derivative
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
253
263
404
On the stability of generalized derivations on Banach algebras
E. Ansari-Piri
e−ansari@guilan.ac.ir
1
E. Anjidani
ehsan−anjidani@guilan.ac.ir
2
University of Guilan
University of Guilan
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
Hyers-Ulam-Rassias stability
generalized
derivation
bounded central approximate identity
faithful Banach
algebra
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
265
274
405
Non-regularity of multiplications for general measure algebras
J. Laali
Laali@tmu.ac.ir
1
M. Ettefagh
etefagh@iaut.ac.ir
2
Kharazmi University
Islamic Azad University
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
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2012-04-01
38
1
275
292
406
Extensions of strongly alpha-reversible rings
L. Zhao
lzhao78@gmail.com
1
X. Zhu
zhuxs@nju.edu.cn
2
Nanjing University
Nanjing University
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
reversible rings
strongly $alpha$-reversible rings
Nil-$alpha$-reversible rings
weakly reversible rings