2012
38
2
2
250
Common fixed points of fweak contractions in cone metric spaces
2
2
Recently, Choudhury and Metiya [Fixed points of weak contractions in cone metric spaces, Nonlinear Analysis 72 (2010) 15891593] proved some fixed point theorems for weak contractions in cone metric spaces. Weak contractions are generalizations of the Banach's contraction mapping, which have been studied by several authors. In this paper, we introduce the notion of $f$weak contractions and also establish a coincidence and common fixed point result for $f$weak contractions in cone metric spaces. Our result is supported by an example which include and generalize the results of Choudhury and Metiya's work.
3

293
303


Wultipol
Sintunavarat
King Mongkut's University of Technology Thonburi (KMUTT)
King Mongkut's University of Technology Thonburi
Thailand
poom_teun@hotmail.com


Poom
Kumam
King Mongkut's University of Technology Thonburi (KMUTT)
King Mongkut's University of Technology Thonburi
Thailand
poom.kum@kmutt.ac.th
Cone metric spaces
Weak contraction
fweak contraction
coincidence point
common fixed point
Rings with a setwise polynomiallike condition
2
2
Let $R$ be an infinite ring. Here we prove that if $0_R$ belongs to ${x_1x_2cdots x_n ;; x_1,x_2,dots,x_nin X}$ for every infinite subset $X$ of $R$, then $R$ satisfies the polynomial identity $x^n=0$. Also we prove that if $0_R$ belongs to ${x_1x_2cdots x_nx_{n+1} ;; x_1,x_2,dots,x_n,x_{n+1}in X}$ for every infinite subset $X$ of $R$, then $x^n=x$ for all $xin R$.
3

305
311


Ali
Tavakoli
Islamic Azad University  Majlesi Branch
Islamic Azad University  Majlesi Branch
Iran
ali_tavakoli_targhi@yahoo.com


Alireza
Abdollahi
University of Isfahan
University of Isfahan
Iran
a.abdollahi@math.ui.ac.ir


Howard E.
Bell
Brock University
Brock University
Canada
hbell@brocku.ca
Primitive rings
Polynomial identities
Combinatorial conditions
A new family in the stable homotopy groups of spheres
2
2
Let $p$ be a prime number greater than three. In this paper, we prove the existence of a new family of homotopy elements in the stable homotopy groups of spheres $pi_{ast}(S)$ which is represented by $h_nh_mtilde{beta}_{s+2}in {rm Ext}_A^{s+4, q[p^n+p^m+(s+2)p+(s+1)]+s}(mathbb{Z}_p,mathbb{Z}_p)$ up to nonzero scalar in the Adams spectral sequence, where $ngeq m+2>5$, $0leq sExt}_A^{s+2,q[(s+2)p+(s+1)]+s}(mathbb{Z}_p,mathbb{Z}_p)$ was defined by X. Wang and Q. Zheng.
3

313
322


Xiugui
Liu
School of Mathematical Sciences and LPMC,
Nankai University,
Tianjin 300071,
P. R China
School of Mathematical Sciences and LPMC,
Nankai
China, R. O. C.
xgliu@nankai.edu.cn


Kai
Ma
Mathematics and Information
Science College,Hebei Normal University, 050016,Shijiazhuang, P. R. China
Mathematics and Information
Science College,Hebei
China, R. O. C.
kaima@163.com
stable homotopy groups of spheres
Adams spectral sequence
May spectral sequence
Branches in random recursive kary trees
2
2
In this paper, using generalized {polya} urn models we find the expected value of the size of a branch in recursive $k$ary trees. We also find the expectation of the number of nodes of a given outdegree in a branch of such trees.
3

323
331


Mehri
Javanian
Javanian
Javanian
Iran
javanian_m@yahoo.com


Mohammad Q.
Vahidi Asl
VahidiAsl
VahidiAsl
Iran
mvahidi@sbu.ac.ir
trees
random recursive trees
generalized P'olya urn models
HorvitzThompson estimator of population mean under inverse sampling designs
2
2
Inverse sampling design is generally considered to be appropriate technique when the population is divided into two subpopulations, one of which contains only few units. In this paper, we derive the HorvitzThompson estimator for the population mean under inverse sampling designs, where subpopulation sizes are known. We then introduce an alternative unbiased estimator, corresponding to poststratification approach. Both of these are not locationinvariant, but this is ignorable for alternative estimator. Using a simulation study, we find that HorvitzThompson estimator is an efficient estimator when the mean of the offinterest subpopulation is close to zero while the alternative estimator appears to be an efficient estimator in general.
3

333
347


Mohammad
Mohammadi
School of Mathematical Science, Isfahan University of Technology, Isfahan, Iran.
School of Mathematical Science, Isfahan University
Iran
m.mohammadi@sci.ui.ac.ir


Mohammad
Salehi Marzijarani
Department of Mathematical Sciences, Isfahan University of Technology 8415683111, Iran;
Department of Mathematics, Statistics and Physics, Qatar University, P.O.Box 2713, Doha, Qatar.
Department of Mathematical Sciences, Isfahan
Iran
salehi_m@cc.iut.ac.ir
Finite Population
Inverse Sampling
Poststratification
Random Sample Size
Comparison results on the preconditioned mixedtype splitting
iterative method for Mmatrix linear systems
2
2
Consider the linear system Ax=b where the coefficient matrix A is an Mmatrix. In the present work, it is proved that the rate of convergence of the GaussSeidel method is faster than the mixedtype splitting and AOR (SOR) iterative methods for solving Mmatrix linear systems. Furthermore, we improve the rate of convergence of the mixedtype splitting iterative method by applying a preconditioned matrix. Comparison theorems show that the rate of convergence of the preconditioned GaussSeidel method is faster than the preconditioned mixedtype splitting and AOR (SOR) iterative methods. Finally, some numerical examples are presented to illustrate the reality of our comparison theorems.
3

349
367


M.
Mohseni Moghadam
Shahid Bahonar University of Kerman
Shahid Bahonar University of Kerman
Iran
mohseni@mail.uk.ac.ir


Fatemeh
Panjeh Ali Beik
ValiAsr University of Rafsanjan
ValiAsr University of Rafsanjan
Iran
f.beik@vru.ac.ir
Linear systems
Mixedtype splitting iterative method
Preconditioned matrix
Mmatrix
An iterative method for amenable semigroup and infinite family of non expansive mappings
in Hilbert spaces
2
2
begin{abstract} In this paper, we introduce an iterative method for amenable semigroup of non expansive mappings and infinite family of non expansive mappings in the frame work of Hilbert spaces. We prove the strong convergence of the proposed iterative algorithm to the unique solution of a variational inequality, which is the optimality condition for a minimization problem. The results presented in this paper mainly extend the corresponding results announced by Qin et al. [X. Qin, Y. J. Cho, and S. M. Kang, An iterative method for an infinite family of nonexpansive mappings in Hilbert spaces, Bull. Malays. Math. Sci. Soc. 32 (2009) 161171] and many others. end{abstract}
3

369
389


Husain
Piri
Department of Mathematics, Bonab Higher Education Complex
Department of Mathematics, Bonab Higher
Iran
husain.piri@gmail.com


Hamid
Vaezi
Faculty of Mathematical Sciences University
of Tabriz, Tabriz, Iran
Faculty of Mathematical Sciences University
of
Iran
hvaezi@tabrizu.ac.ir
common fixed point
strong convergence
Amenable semigroup
Recurrent metrics in the geometry of second order differential equations
2
2
Given a pair (semispray $S$, metric $g$) on a tangent bundle, the family of nonlinear connections $N$ such that $g$ is recurrent with respect to $(S, N)$ with a fixed recurrent factor is determined by using the Obata tensors. In particular, we obtain a characterization for a pair $(N, g)$ to be recurrent as well as for the triple $(S, stackrel{c}{N}, g)$ where $stackrel{c}{N}$ is the canonical nonlinear connection of the semispray $S$. Also, the Weyl connection of conformal gauge theories is obtained as a particular case.
3

391
401


Mircea
Crasmareanu
Faculty of Mathematics
University "Al. I. Cuza"
Iasi, 700506
Faculty of Mathematics
University "Al. I.
Romania
mcrasm@uaic.ro
Semispray
nonlinear connection
recurrent metric
Obata operators
Projective maximal submodules of extending regular modules
2
2
We show that a projective maximal submodule of afinitely generated, regular, extending module is a directsummand. Hence, every finitely generated, regular, extendingmodule with projective maximal submodules is semisimple. As aconsequence, we observe that every regular, hereditary, extendingmodule is semisimple. This generalizes and simplifies a result of Dung and Smith. As another consequence, we observe thatevery right continuous ring, whose maximal right ideals areprojective, is semisimple Artinian. This generalizes some resultsof Osofsky and Karamzadeh. We also observe thatfour classes of rings, namely right $aleph_0$continuous rings,right continuous rings, right $aleph_0$continuous regular ringsand right continuous regular rings are not axiomatizable.
3

403
412


E.
Momtahan
Yasouj University
Yasouj University
Iran
continuous rings
extending rings
regular rings
aleph_0selfinjective rings
Finite pgroups with few nonlinear irreducible character kernels
2
2
Abstract. In this paper, we classify all of the ﬁnite pgroups with at most three non linear irreducible character kernels.
3

413
422


Hossein
Doostie
Tarbiat Moallem University
Tarbiat Moallem University
Iran
doostih@tmu.as.ir


Amin
Saeidi
Tarbiat Moallem University
Tarbiat Moallem University
Iran
saeidi.amin@gmail.com
Minimal normal subgroups
few character kernels
strong and weak conditions
Invariance of the barycentric subdivision of a simplicial complex
2
2
In this paper we prove that a simplicial complex is determined uniquely up to isomorphism by its barycentric subdivision as well as its comparability graph. We also put together several algebraic, combinatorial and topological invariants of simplicial complexes.
3

423
432


Rashid
ZaareNahandi
Institute for Advanced Studies in Basic Sciences
Institute for Advanced Studies in Basic Sciences
Iran
rashidzn@iasbs.ac.ir
Simplicial complex
comparability graph
barycentric subdivision
On Rickart modules
2
2
Let $R$ be an arbitrary ring with identity and $M$ a right $R$module with $S=$ End$_R(M)$. The module $M$ is called {it Rickart} if for any $fin S$, $r_M(f)=Se$ for some $e^2=ein S$. We prove that some results of principally projective rings and Baer modules can be extended to Rickart modules for this general settings.
3

433
445


S
Agayev
Eropean University of Lefke, Cyprus
Eropean University of Lefke, Cyprus
Cyprus


S
Halicioglu
Department of Mathematics
Ankara University
Department of Mathematics
Ankara University
Turkey
halici@ankara.edu.tr


A
Harmanci
Hacettepe University, Turkey
Hacettepe University, Turkey
Turkey
Rickart modules
Baer modules
reduced modules
rigid modules
Optimal order finite element approximation for a hyperbolic integrodifferential equation
2
2
Semidiscrete finite element approximation of a hyperbolic type integrodifferential equation is studied. The model problem is treated as the wave equation which is perturbed with a memory term. Stability estimates are obtained for a slightly more general problem. These, based on energy method, are used to prove optimal order a priori error estimates.
3

447
459


Fardin
Saedpanah
University of Kurdistan,
Department of Mathematics
University of Kurdistan,
Department of Mathematic
Iran
f_saedpanah@yahoo.com
finite element method
wave equation
integrodifferential equation
Stability
a priori error estimate
Properties of multivalent functions associated with certain integral operator
2
2
Let A(p) denote the class of functions which are analytic in the open unit disk U. By making use of certain integral operator,we obtain some interesting properties of multivalent analytic functions.
3

461
468


JinLin
Liu
Department of Mathematics, Yangzhou University
Department of Mathematics, Yangzhou University
China, R. O. C.
jlliu@yzu.edu.cn
Multivalent function
analytic function
integral operator
Applications of epiretractable modules
2
2
An Rmodule M is called epiretractable if every submodule of MR is a homomorphic image of M. It is shown that if R is a right perfect ring, then every projective slightly compressible module MR is epiretractable. If R is a Noetherian ring, then every epiretractable right Rmodule has direct sum of uniform submodules. If endomorphism ring of a module MR is vonNeumann regular, then M is semisimple if and only if M is epiretractable. If R is a quasi Frobenius ring, then R is a right hereditary ring if and only if every injective right Rmodule is semisimple. A ring R is semisimple if and only if R is right hereditary and every epiretractable right Rmodule is projective. Moreover, a ring R is semisimple if and only if R is a pri and vonNeumann regular.
3

469
477


Bashishth
Pandeya
Department of Applied Mathematics, Institute of Technology, Banaras Hindu University,
Varanasi221005, India.
Department of Applied Mathematics, Institute
India
bmpandeya@bhu.ac.in


Avanish
Chaturvedi
Department of Mathematics, Jaypee Institute of Information Technology,
(Deemed University) A10, Sector62, Noida201307 (UP), India
Department of Mathematics, Jaypee Institute
India
akc99@rediffmail.com


Ashok
Gupta
Department of Applied Mathematics, Institute of Technology, Banaras Hindu University,
Varanasi221005, India.
Department of Applied Mathematics, Institute
India
ashokg@bhu.ac.in
Epiretractable modules
semisimple rings
Perfect rings
Hereditary rings
vonNumann regular rings
Some vector fields on a riemannian manifold with semisymmetric metric connection
2
2
In the first part of this paper, some theorems are given for a Riemannian manifold with semisymmetric metric connection. In the second part of it, some special vector fields, for example, torseforming vector fields, recurrent vector fields and concurrent vector fields are examined in this manifold. We obtain some properties of this manifold having the vectors mentioned above.
3

479
490


Füsun
Özen Zengin
Istanbul Technical University
Istanbul Technical University
Turkey
fozen@itu.edu.tr


Sezgin
Altay Demirbag
Istanbul Technical University
Istanbul Technical University
Turkey
saltay@itu.edu.tr


S. Aynur
Uysal
Dogus University
Dogus University
Turkey
auysal@dogus.edu.tr


Hülya
Bagdatli Yilmaz
Marmara University
Marmara University
Turkey
hbagdatli@marmara.edu.tr
Semisymmetric metric connection
sectional curvature
conformally flat manifold
pseudo symmetric manifold
concircular vector field
Riordan group approaches in matrix factorizations
2
2
In this paper, we consider an arbitrary binary polynomial sequence {A_n} and then give a lower triangular matrix representation of this sequence. As main result, we obtain a factorization of the innite generalized Pascal matrix in terms of this new matrix, using a Riordan group approach. Further some interesting results and applications are derived.
3

491
506


Emrah
Kilic
TOBB University of Economics and Technology Mathematics Department
TOBB University of Economics and Technology
Turkey
ekilic@etu.edu.tr


Nese
Omur
Kocaeli University Mathematics Department
Kocaeli University Mathematics Department
Turkey
neseomur@kocaeli.edu.tr


Gulfer
Tatar
Kocaeli University Mathematics Department
Kocaeli University Mathematics Department
Turkey
gulfera@kocaeli.edu.tr
Riordan Group
Factorization
Binary Recurrences
Pascal Matrix
Some homological properties of amalgamated duplication of a ring along an ideal
2
2
In this work, we investigate the transfer of some homological properties from a ring $R$ to its amalgamated duplication along some ideal $I$ of $R$ $Rbowtie I$, and then generate new and original families of rings with these properties.
3

507
515


Mohamed
Chhiti
University of Fez, Fez, Morocco
University of Fez, Fez, Morocco
Morocco
chhiti.med@hotmail.com


Najib
Mahdou
Department of Mathematics, Faculty of Sciences and Technology, University of Fez, Fez, Morocco.
Department of Mathematics, Faculty of Sciences
Morocco
mahdou@hotmail.com
Amalgamated
Perfect ring
(n
d)ring
A note on the socle of certain types of frings
2
2
For any reduced commutative $f$ring with identity and bounded inversion, we show that a condition which is obviously necessary for the socle of the ring to coincide with the socle of its bounded part, is actually also sufficient. The condition is that every minimal ideal of the ring consist entirely of bounded elements. It is not too stringent, and is satisfied, for instance, by rings of continuous functions.
3

517
528


Themba
Dube
University of South Africa
University of South Africa
South Africa
tdube2013@yahoo.co.za
frame
function rings
ideal
socle
Ring structures of mod p equivariant cohomology rings and ring homomorphisms between them
2
2
In this paper, we consider a class of connected oriented (with respect to Z/p) closed Gmanifolds with a nonempty finite fixed point set, each of which is Gequivariantly formal, where G = Z/p and p is an odd prime. Using localization theorem and equivariant index, we give an explicit description of the mod p equivariant cohomology ring of such a Gmanifold in terms of algebra. This makes it possible to determine the number of equivariant cohomology rings (up to isomorphism) of such 2dimensional Gmanifolds. Moreover, we obtain a description of the ring homomorphism between equivariant cohomology rings of such two Gmanifolds induced by a Gequivariant map, and show a characterization of the ring homomorphism.
3

529
542


Yanchang
Chen
College of Mathematics and Information Science, Hebei Normal University, Yuhua
Road 113, Shijiazhuang 050016, P. R. China
College of Mathematics and Information Science,
China, R. O. C.
cyc810707@163.com


Yanying
Wang
College of Mathematics and Information Science, Hebei Normal University, Yuhua Road 113, Shijiazhuang 050016, P. R. China
College of Mathematics and Information Science,
China, R. O. C.
wyanying2003@yahoo.com.cn
Gmanifold
equivariant index
equivariant cohomology
ring homomorphism