Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Common fixed points of f-weak contractions in cone metric spaces 293 303 218 EN Wultipol Sintunavarat King Mongkut's University of Technology Thonburi (KMUTT) Poom Kumam King Mongkut's University of Technology Thonburi (KMUTT) Journal Article 2010 05 05 Recently, Choudhury and Metiya [Fixed points of weak contractions in <br />cone metric spaces, Nonlinear Analysis 72 (2010) 1589-1593] proved <br />some fixed point theorems for weak contractions in cone metric <br />spaces. Weak contractions are generalizations of the Banach's <br />contraction mapping, which have been studied by several authors. In <br />this paper, we introduce the notion of \$f\$-weak contractions and <br />also establish a coincidence and common fixed point result for <br />\$f\$-weak contractions in cone metric spaces. Our result is supported <br />by an example which include and generalize the results of Choudhury <br />and Metiya's work. http://bims.iranjournals.ir/article_218_d595625aa45af7f415864e2b1458807a.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Rings with a setwise polynomial-like condition 305 311 231 EN Ali Tavakoli Islamic Azad University - Majlesi Branch Alireza Abdollahi University of Isfahan Howard E. Bell Brock University Journal Article 2010 04 20 Let \$R\$ be an infinite ring. Here we <br />prove that if \$0_R\$ belongs to \${x_1x_2cdots x_n ;|; <br />x_1,x_2,dots,x_nin X}\$ for every infinite subset \$X\$ of \$R\$, <br />then \$R\$ satisfies the polynomial identity \$x^n=0\$. Also we prove <br />that if \$0_R\$ belongs to \${x_1x_2cdots <br />x_n-x_{n+1} ;|; x_1,x_2,dots,x_n,x_{n+1}in X}\$ for every <br />infinite subset \$X\$ of \$R\$, then \$x^n=x\$ for all \$xin R\$. http://bims.iranjournals.ir/article_231_c96d633637c016b61c15d2693daeeffb.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 A new family in the stable homotopy groups of spheres 313 322 204 EN Xiugui Liu School of Mathematical Sciences and LPMC, Nankai University, Tianjin 300071, P. R China Kai Ma Mathematics and Information Science College,Hebei Normal University, 050016,Shijiazhuang, P. R. China Journal Article 2010 06 19 Let \$p\$ be a prime number greater than three. In this paper, we <br />prove the existence of a new family of homotopy elements in the <br />stable homotopy groups of spheres \$pi_{ast}(S)\$ which is <br />represented by \$h_nh_mtilde{beta}_{s+2}in {rm Ext}_A^{s+4, <br />q[p^n+p^m+(s+2)p+(s+1)]+s}(mathbb{Z}_p,mathbb{Z}_p)\$ up to nonzero <br />scalar in the Adams spectral sequence, where \$ngeq m+2>5\$, \$0leq <br />s<br />Ext}_A^{s+2,q[(s+2)p+(s+1)]+s}(mathbb{Z}_p,mathbb{Z}_p)\$ was <br />defined by X. Wang and Q. Zheng. http://bims.iranjournals.ir/article_204_3e0a128f7a5b367bd3351fe6549af39e.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Branches in random recursive k-ary trees 323 331 200 EN Mehri Javanian Javanian Mohammad Q. Vahidi Asl Vahidi-Asl Journal Article 2010 05 30 In this paper, using generalized {polya} urn <br />models we find the expected value of the size of a branch in <br />recursive \$k\$-ary trees. We also find the expectation of the <br />number of nodes of a given outdegree in a branch of such <br />trees. http://bims.iranjournals.ir/article_200_0fb18b5d341305095aa3c67a34c101b0.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Horvitz-Thompson estimator of population mean under inverse sampling designs 333 347 255 EN Mohammad Mohammadi School of Mathematical Science, Isfahan University of Technology, Isfahan, Iran. Mohammad Salehi Marzijarani Department of Mathematical Sciences, Isfahan University of Technology 84156-83111, Iran; Department of Mathematics, Statistics and Physics, Qatar University, P.O.Box 2713, Doha, Qatar. Journal Article 2010 03 25 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 Horvitz-Thompson estimator for the population mean under inverse sampling designs, where subpopulation sizes are known. We then introduce an alternative <br /> unbiased estimator, corresponding to post-stratification approach. Both of these are not location-invariant, but this is ignorable for alternative estimator. <br />Using a simulation study, we find that Horvitz-Thompson estimator is an efficient estimator when the mean of the off-interest subpopulation is close to zero while the alternative estimator appears to be an efficient estimator in general. http://bims.iranjournals.ir/article_255_8bc393a21f635d83fc2a4bdda66f1e39.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Comparison results on the preconditioned mixed-type splitting iterative method for M-matrix linear systems 349 367 211 EN M. Mohseni Moghadam Shahid Bahonar University of Kerman Fatemeh Panjeh Ali Beik Vali-Asr University of Rafsanjan Journal Article 2010 09 03 Consider the linear system Ax=b where the coefficient <br />matrix A is an M-matrix. In the present work, it is proved <br />that the rate of convergence of the Gauss-Seidel method is faster <br />than the mixed-type splitting and AOR (SOR) iterative methods for <br />solving M-matrix linear systems. Furthermore, we improve the rate <br />of convergence of the mixed-type splitting iterative method by <br />applying a preconditioned matrix. Comparison theorems show that <br />the rate of convergence of the preconditioned Gauss-Seidel method <br />is faster than the preconditioned mixed-type splitting and AOR <br />(SOR) iterative methods. Finally, some numerical examples are <br />presented to illustrate the reality of our comparison theorems. http://bims.iranjournals.ir/article_211_dc5b9e9e1b2a179a471b622100c26a58.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 An iterative method for amenable semigroup and infinite family of non expansive mappings in Hilbert spaces 369 389 207 EN Husain Piri Department of Mathematics, Bonab Higher Education Complex Hamid Vaezi Faculty of Mathematical Sciences University of Tabriz, Tabriz, Iran Journal Article 2011 02 25 begin{abstract} <br />In this paper, we introduce an iterative method for amenable <br />semigroup of non expansive mappings and infinite family of non <br />expansive mappings in the frame work of Hilbert spaces. We prove the <br />strong convergence of the proposed iterative algorithm to the unique <br />solution of a variational inequality, which is the optimality <br />condition for a minimization problem. The results presented in this <br />paper mainly extend the corresponding results announced by Qin et <br />al. [X. Qin, Y. J. Cho, and S. M. Kang, An iterative method for an <br />infinite family of non-expansive mappings in Hilbert spaces, Bull. <br />Malays. Math. Sci. Soc. 32 (2009) 161-171] and many others. <br /> <br />end{abstract} http://bims.iranjournals.ir/article_207_7d5d8ff16fbbbca2e1790a0f9ab74c87.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2011 02 23 Recurrent metrics in the geometry of second order differential equations 391 401 215 EN Mircea Crasmareanu Faculty of Mathematics University "Al. I. Cuza" Iasi, 700506 Journal Article 2011 02 09 Given a pair (semispray \$S\$, metric \$g\$) on a tangent bundle, the <br />family of nonlinear connections \$N\$ such that \$g\$ is recurrent <br />with respect to \$(S, N)\$ with a fixed recurrent factor is <br />determined by using the Obata tensors. In particular, we obtain a <br />characterization for a pair \$(N, g)\$ to be recurrent as well as <br />for the triple \$(S, stackrel{c}{N}, g)\$ where \$stackrel{c}{N}\$ <br />is the canonical nonlinear connection of the semispray \$S\$. Also, <br />the Weyl connection of conformal gauge theories is obtained as a particular <br />case. http://bims.iranjournals.ir/article_215_dcd58d4931f7da614e2cbc66aa27cade.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Projective maximal submodules of extending regular modules 403 412 407 EN E. Momtahan Yasouj University Journal Article 2009 04 30 We show  that a projective maximal submodule of a<br />finitely generated, regular, extending module is a direct<br />summand. Hence, every finitely generated, regular, extending<br />module with projective maximal submodules is semisimple. As a<br />consequence, we observe that every regular, hereditary, extending<br />module is semisimple. This generalizes and simplifies a result of<br />  Dung and   Smith. As another consequence, we observe that<br />every right continuous ring, whose maximal right ideals are<br />projective, is semisimple Artinian. This generalizes some results<br />of   Osofsky and   Karamzadeh. We also observe that<br />four classes of rings, namely right \$aleph_0\$-continuous rings,<br />right continuous rings, right \$aleph_0\$-continuous regular rings<br />and right continuous regular rings are not axiomatizable. http://bims.iranjournals.ir/article_407_6a4d7f84d031275eb5d254f9f2871b8d.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Finite p-groups with few non-linear irreducible character kernels 413 422 208 EN Hossein Doostie Tarbiat Moallem University Amin Saeidi Tarbiat Moallem University Journal Article 2009 04 30 Abstract. In this paper, we classify all of the ﬁnite p-groups with at most three non linear irreducible character kernels. http://bims.iranjournals.ir/article_208_69f56c704b32022bc49cb06797e62448.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Invariance of the barycentric subdivision of a simplicial complex 423 432 212 EN Rashid Zaare-Nahandi Institute for Advanced Studies in Basic Sciences Journal Article 2010 10 25 ‎In this paper we prove that a simplicial complex is determined‎ <br />‎uniquely up to isomorphism by its barycentric subdivision as well as‎ <br />‎its comparability graph‎. ‎We also put together several algebraic‎, <br />‎combinatorial and topological invariants of simplicial complexes‎. http://bims.iranjournals.ir/article_212_de5bc8c7b7b3dc3bfb85ee068f5d21f6.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 On Rickart modules 433 445 209 EN S Agayev Eropean University of Lefke, Cyprus S Halicioglu Department of Mathematics Ankara University A Harmanci Hacettepe University, Turkey Journal Article 2010 09 26 Let \$R\$ be an arbitrary ring with <br />identity and \$M\$ a right \$R\$-module with \$S=\$ End\$_R(M)\$. The <br />module \$M\$ is called {it Rickart} if for any \$fin S\$, <br />\$r_M(f)=Se\$ for some \$e^2=ein S\$. We prove that some results of <br />principally projective rings and Baer modules can be extended to <br />Rickart modules for this general settings. http://bims.iranjournals.ir/article_209_a482f3c0119843e2d96bfda7f6af9907.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Optimal order finite element approximation for a hyperbolic‎ ‎integro-differential equation 447 459 201 EN Fardin Saedpanah University of Kurdistan, Department of Mathematics Journal Article 2010 10 26 ‎Semidiscrete finite element approximation of a hyperbolic type‎ <br />‎integro-differential equation is studied. The model problem is‎ <br />‎treated as the wave equation which is perturbed with a memory term.‎ <br />‎Stability estimates are obtained for a slightly more general problem.‎ <br />‎These, based on energy method, are used to prove optimal order‎ <br />‎a priori error estimates.‎ http://bims.iranjournals.ir/article_201_e72a83b9b71c31f92537ef2e58b72810.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Properties of multivalent functions associated with certain integral operator 461 468 198 EN Jin-Lin Liu Department of Mathematics, Yangzhou University Journal Article 2009 07 05 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. http://bims.iranjournals.ir/article_198_05b363674deba2ef06e6925dc08db279.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Applications of epi-retractable modules 469 477 202 EN Bashishth Muni Pandeya Department of Applied Mathematics, Institute of Technology, Banaras Hindu University, Varanasi-221005, India. Avanish Kumar Chaturvedi Department of Mathematics, Jaypee Institute of Information Technology, (Deemed University) A-10, Sector-62, Noida-201307 (UP), India Ashok Ji Gupta Department of Applied Mathematics, Institute of Technology, Banaras Hindu University, Varanasi-221005, India. Journal Article 2010 09 17 An R-module M is called epi-retractable 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 epi-retractable. If R is a Noetherian ring, then every epi-retractable right R-module has direct sum of uniform submodules. If endomorphism ring of a module MR is von-Neumann regular, then M is semi-simple if and only if M is epi-retractable. If R is a quasi Frobenius ring, then R is a right hereditary ring if and only if every injective right R-module is semi-simple. A ring R is semi-simple if and only if R is right hereditary and every epiretractable right R-module is projective. Moreover, a ring R is semi-simple if and only if R is a pri and von-Neumann regular. http://bims.iranjournals.ir/article_202_388757ddee7a3a67ab050c9a998e2049.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Some vector fields on a riemannian manifold with semi-symmetric metric connection 479 490 203 EN Füsun Özen Zengin Istanbul Technical University Sezgin Altay Demirbag Istanbul Technical University S. Aynur Uysal Dogus University Hülya Bagdatli Yilmaz Marmara University Journal Article 2010 07 19 In the first part of this paper, some theorems are given for a Riemannian manifold with semi-symmetric metric connection. In the second part of it, some special vector fields, for example, torse-forming 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. http://bims.iranjournals.ir/article_203_231ecca82cd01017b92531f34000f4d6.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Riordan group approaches in matrix factorizations 491 506 205 EN Emrah Kilic TOBB University of Economics and Technology Mathematics Department Nese Omur Kocaeli University Mathematics Department Gulfer Tatar Kocaeli University Mathematics Department Journal Article 2009 08 07 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 in nite generalized Pascal matrix in terms of this new matrix, <br />using a Riordan group approach. Further some interesting results <br />and applications are derived. http://bims.iranjournals.ir/article_205_da5f4f10d7f10a4b73c7db3f21ccb967.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Some homological properties of amalgamated duplication of a ring along an ideal 507 515 210 EN Mohamed Chhiti University of Fez, Fez, Morocco Najib Mahdou Department of Mathematics, Faculty of Sciences and Technology, University of Fez, Fez, Morocco. Journal Article 2010 10 17 In this work, we investigate the transfer of some homological <br />properties from a ring \$R\$ to its amalgamated duplication along <br />some ideal \$I\$ of \$R\$ \$Rbowtie I\$, and then generate new and <br />original families of rings with these properties. http://bims.iranjournals.ir/article_210_485789e3f153661d4d8c1136c73cb0d1.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 A note on the socle of certain types of f-rings 517 528 214 EN Themba Dube University of South Africa Journal Article 2010 08 15 For any reduced commutative \$f\$-ring with identity and bounded <br />inversion, we show that a condition which is obviously necessary for <br />the socle of the ring to coincide with the socle of its bounded <br />part, is actually also sufficient. The condition is that every <br />minimal ideal of the ring consist entirely of bounded elements. It <br />is not too stringent, and is satisfied, for instance, by rings of <br />continuous functions. http://bims.iranjournals.ir/article_214_3c1783bf3988903f43f20700e3e575bc.pdf
Springer and the Iranian Mathematical Society (IMS) Bulletin of the Iranian Mathematical Society 1017-060X 38 2 2012 07 15 Ring structures of mod p equivariant cohomology rings and ring homomorphisms between them 529 542 217 EN Yanchang Chen College of Mathematics and Information Science, Hebei Normal University, Yuhua Road 113, Shijiazhuang 050016, P. R. China Yanying Wang College of Mathematics and Information Science, Hebei Normal University, Yuhua Road 113, Shijiazhuang 050016, P. R. China Journal Article 2010 10 18 In this paper, we consider a class of connected oriented (with respect to Z/p) closed G-manifolds with a non-empty finite fixed point set, each of which is G-equivariantly 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 G-manifold in terms of algebra. This makes it possible to determine the number of equivariant cohomology rings (up to isomorphism) of such 2-dimensional G-manifolds. Moreover, we obtain a description of the ring homomorphism between equivariant cohomology rings of such two G-manifolds induced by a G-equivariant map, and show a characterization of the ring homomorphism. http://bims.iranjournals.ir/article_217_d78bd5727580f199e3b327f8189d5d8a.pdf