Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
Solving integral equations of the third kind in the reproducing kernel space
543
551
EN
Fazhan
Geng
Department of Mathematics, changshu Institute of Technology, Changshu, China.
gengfazhan@sina.com
A reproducing kernel Hilbert space restricts the space of functions to smooth functions and has structure for function approximation and some aspects in learning theory. In this paper, the solution of an integral equation of the third kind is constructed analytically using a new method. The analytical solution is represented in the form of series in the reproducing kernel space. Some numerical examples are studied to demonstrate the accuracy of the present method. Results obtained by the method are compared with the exact solution of each example and are found to be in good agreement with each other.
Analytical solution,integral equations of the third kind,reproducing kernel
http://bims.iranjournals.ir/article_213.html
http://bims.iranjournals.ir/article_213_31be77a7aad4602e56a94864ad5882f2.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
On generalized topologies arising from
mappings
553
565
EN
Vladimir
Pavlovic
University of Nis, Faculty of Sciences and Mathematics
vlada@pmf.ni.ac.rs
Aleksandar
S.
Cvetkovi' c
Department of Mathematics and Informatics, Faculty of Mechancial Engineering, University
of Belgrade
acvetkovic@mas.bg.ac.rs
Given a mapping $f:Xto X$ we naturally associate to it a monotonic map $gg_f:exp Xto exp X$ from the power set of $X$ into itself, thus inducing a generalized topology on $X$. In this paper we investigate some properties of generalized topologies which are defined by such a procedure.
Generalized topologies,generalized neighborhood systems,product of generalized topologies
http://bims.iranjournals.ir/article_220.html
http://bims.iranjournals.ir/article_220_44f92411e606144e9eb9f38b332d54d1.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
G-frames and their duals for Hilbert C*-modules
567
580
EN
Azadeh
Alijani
Ph.D student of Vali-e-Asr University
alijani@vru.ac.ir
Mohammad Ali
Dehghan
Staff of Vali-e-Asr university
dehghan@vru.ac.ir
Abstract. Certain facts about frames and generalized frames (g- frames) are extended for the g-frames for Hilbert C*-modules. It is shown that g-frames for Hilbert C*-modules share several useful properties with those for Hilbert spaces. The paper also character- izes the operators which preserve the class of g-frames for Hilbert C*-modules. Moreover, a necessary and suffcient condition is ob- tained for an operator T whose corresponding singleton set {T} to be a g-frame. Finally, some characterizations of dual g-frames for Hilbert spaces and Hilbert C*-modules are given.
dual g-frame,g-Bessel sequence,g-frame,Hilbert C*-module
http://bims.iranjournals.ir/article_206.html
http://bims.iranjournals.ir/article_206_9ada6846e5a0d425c990156f9766f580.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
The starlikeness, convexity, covering theorem and extreme points of p-harmonic mappings
581
596
EN
Qiuhong
Luo
Department of Mathematics,
Hunan Normal University, Changsha, Hunan 410081, People's Republic
of China.
luoqiuhong2004120314@126.com
Xiantao
Wang
Hunan Normal University of China
wangxt1965@yahoo.com.cn
The main aim of this paper is to introduce three classes $H^0_{p,q}$, $H^1_{p,q}$ and $TH^*_p$ of $p$-harmonic mappings and discuss the properties of mappings in these classes. First, we discuss the starlikeness and convexity of mappings in $H^0_{p,q}$ and $H^1_{p,q}$. Then establish the covering theorem for mappings in $H^1_{p,q}$. Finally, we determine the extreme points of the class $TH^*_{p}$.
$p$-harmonic mapping,univalence,starlikeness,Convexity,extreme point
http://bims.iranjournals.ir/article_224.html
http://bims.iranjournals.ir/article_224_ef60efaae2872ad5d035ebe7683c92ed.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
Optimal inequalities for the power, harmonic and logarithmic means
597
606
EN
Yuming
Chu
Huzhou Teachers College
chuyuming@hutc.zj.cn
Mingyu
Shi
Hebei University
mingyulj08@163.com
Yueping
Jiang
Hunan University
ypjiang731@163.com
For all $a,b>0$, the following two optimal inequalities are presented: $H^{alpha}(a,b)L^{1-alpha}(a,b)geq M_{frac{1-4alpha}{3}}(a,b)$ for $alphain[frac{1}{4},1)$, and $ H^{alpha}(a,b)L^{1-alpha}(a,b)leq M_{frac{1-4alpha}{3}}(a,b)$ for $alphain(0,frac{3sqrt{5}-5}{40}]$. Here, $H(a,b)$, $L(a,b)$, and $M_p(a,b)$ denote the harmonic, logarithmic, and power means of order $p$ of two positive numbers $a$ and $b$, respectively.
Power mean,logarithmic mean,harmonic mean
http://bims.iranjournals.ir/article_225.html
http://bims.iranjournals.ir/article_225_148114bdbc407891af23dda972ab8b96.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
The existence results for a coupled system of nonlinear fractional differential equations with multi-point boundary conditions
607
624
EN
Yi
Chen
School of Mathematical Sciences and Computing Technology, Central South University, Changsha, Hunan 410083, P.R.China
chenyimathcsu@163.com
Dezhu
Chen
School of Mathematical Sciences and Computing Technology, Central South University, Changsha, Hunan 410083, P.R.China
cdz.2009@163.com
Zhanmei
Lv
School of Mathematical Sciences and Computing Technology, Central South University, Changsha, Hunan 410083, P.R.China
cy2008csu@163.com
In this paper, we study a coupled system of nonlinear fractional diﬀerential equations with multi-point boundary condi- tions. The diﬀerential operator is taken in the Riemann-Liouville sense. Applying the Schauder ﬁxed-point theorem and the contrac- tion mapping principle, two existence results are obtained for the following system D^{alpha}_{0+}x(t)=fleft(t,y(t),D^{p}_{0+}y(t)right), t in (0,1), D^{beta}_{0+}y(t)=gleft(t,x(t),D^{q}_{0+}x(t)right), t in (0,1), x(0)=x'(0)=x''(0)=cdots=x^{(m-2)}(0)=0, x(1)=lambda x(xi) ,0y(0)=y',(0)=y''(0)=cdots=y^{(m-2)},(0)=0, y(1)=lambda y(xi) , 0where m in mathbb{N}, m geq 2,alpha,,beta in (m-1,m) and alpha,beta,p,q,lambda satisfy certain conditions.
Fractional differential equations,Boundary value problem,Schauder fixed-point theorem,Contraction mapping principle
http://bims.iranjournals.ir/article_227.html
http://bims.iranjournals.ir/article_227_1cb83ef69ed98227526e88224cdc5a93.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
Some results on weakly contractive maps
625
645
EN
Stojan
Radenovi'c
University of Belgrade, Faculty of Mechanical Engineering
radens@beotel.net
Zoran
Kadelburg
University of Belgrade, Faculty of Mathematics
kadelbur@matf.bg.ac.rs
Davorka
Jandrli'c
University of Belgrade, Faculty of Mechanical Engineering
djandrlic@mas.bg.ac.rs
Andrija
Jandrli'c
University of Belgrade, Faculty of Mechanical Engineering
ajandrlic@mas.bg.ac.rs
In this paper direct proofs of some common fixed point results for two and three mappings under weak contractive conditions are given. Some of these results are improved by using different arguments of control functions. Examples are presented showing that some generalizations cannot be obtained and also that our results are distinct from the existing ones.
common fixed point,Generalized weak contraction,Generalized quasicontraction,coincidence point
http://bims.iranjournals.ir/article_229.html
http://bims.iranjournals.ir/article_229_7b26b9bcf68af2ce39f7be6598566fe7.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
2-quasirecognizability of the simple groups B_n(p) and C_n(p) by prime graph
647
668
EN
Mahnaz
Foroudi Ghasemabadi
Tarbiat Modares University
mahnaz_mat@yahoo.com
Ali
Iranmanesh
Tarbiat Modares University
iranmana@yahoo.com
Let G be a finite group and let $GK(G)$ be the prime graph of G. We assume that $n$ is an odd number. In this paper, we show that if $GK(G)=GK(B_n(p))$, where $ngeq 9$ and $pin {3,5,7}$, then G has a unique nonabelian composition factor isomorphic to $B_n(p)$ or $C_n(p)$ . As consequences of our result, $B_n(p)$ is quasirecognizable by its spectrum and also by a new proof, the validity of a conjecture of W. J. Shi for $B_n(p)$ is obtained.
Quasirecognition,Prime graph,simple group,element order
http://bims.iranjournals.ir/article_260.html
http://bims.iranjournals.ir/article_260_29bf80f6b23d834cbe7f14a4ad0701d5.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
Identification of Riemannian foliations on the
tangent bundle via SODE structure
669
688
EN
Abolghasem
Laleh
Amirkabir University of Technology
aglaleh@alzahra.ac.ir
Morteza
Mir Mohamad Rezaii
Amirkabir University of Technology
mmreza@aut.ac.ir
Fateme
Ahangari
Amirkabir University of Technology
fa.ahangari@aut.ac.ir
The geometry of a system of second order differential equations is the geometry of a semispray, which is a globally defined vector field on TM. The metrizability of a given semispray is of special importance. In this paper, the metric associated with the semispray S is applied in order to study some types of foliations on the tangent bundle which are compatible with SODE structure. Indeed, sufficient conditions for the metric associated with the semispray S are obtained to extend to a bundle-like metric for the lifted foliation on TM. Thus, the lifted foliation converts to a Riemanian foliation on the tangent space which is adapted to the SODE structure. Particularly, the metrizability property of the semispray S is applied in order to induce SODE structure on transversals. Finally, some equivalent conditions are presented for the transversals to be totally geodesic.
Bundle-like metric,SODE,Semispray,Metrizability,Riemannian
Foliation
http://bims.iranjournals.ir/article_232.html
http://bims.iranjournals.ir/article_232_1c2426a4a61dca0c1d59277a7d46f0c0.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
On Jordan left derivations and generalized Jordan left derivations of matrix rings
689
698
EN
Nader
Mohammad
Ghosseiri
Academic member of University of Kurdistan
mnghosseiri@yahoo.com
Abstract. Let R be a 2-torsion free ring with identity. In this paper, first we prove that any Jordan left derivation (hence, any left derivation) on the full matrix ringMn(R) (n 2) is identically zero, and any generalized left derivation on this ring is a right centralizer. Next, we show that if R is also a prime ring and n 1, then any Jordan left derivation on the ring Tn(R) of all n×n upper triangular matrices over R is a left derivation, and any generalized Jordan left derivation on Tn(R) is a generalized left derivation. Moreover, we prove that any generalized left derivation on Tn(R) is decomposed into the sum of a right centralizer and a Jordan left derivation. Some related results are also obtained.
Prime ring,left derivation,Jordan left derivation,generalized left derivation,generalized Jordan left derivation
http://bims.iranjournals.ir/article_234.html
http://bims.iranjournals.ir/article_234_895b2b8aa0bd6657b0ab13d745aec4c5.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
Convergence theorems of an implicit iteration process for asymptotically pseudocontractive mappings
699
713
EN
Liping
Yang
Guangdong University of Technology
yanglping2003@126.com
The purpose of this paper is to study the strong convergence of an implicit iteration process with errors to a common fixed point for a finite family of asymptotically pseudocontractive mappings and nonexpansive mappings in normed linear spaces. The results in this paper improve and extend the corresponding results of Xu and Ori, Zhou and Chang, Sun, Yang and Yu in some aspects.
implicit iteration process,Asymptotically pseudocontractive mappings,nonexpansive mappings,Normed linear spaces,fixed point
http://bims.iranjournals.ir/article_235.html
http://bims.iranjournals.ir/article_235_69b9f07c099fb6347d20b877bf0c58f5.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
Applying Buchberger's criteria on Montes's DisPGB algorithm
715
724
EN
Amir
Hashemi
Isfahan university of technology
amir.hashemi@cc.iut.ac.ir
Mahdi
Dehghani Darmian
Isfahan University of Technology
mahdi_math_63@yahoo.com
Benyamin
M.-Alizadeh
Isfahan University of Technology
benyamin.m.alizadeh@gmail.com
The concept of comprehensive Grobner bases was introduced by Weispfenning. Montes has proposed an efficient algorithm for computing these bases. But he has not explicitly used Buchberger's criteria in his algorithm. In this paper we prove that we can apply these criteria on Montes algorithm. We propose a modified version of Montes algorithm and evaluate its performance via some examples.
Grobner bases,Comprehensive Grobner bases,DisPGB algorithm
http://bims.iranjournals.ir/article_236.html
http://bims.iranjournals.ir/article_236_ca40dd8662a34869eb72d1e96231c32d.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
varphi-amenability of Banach algebras
725
738
EN
Ali
Ghaffari
Semnan University
aghaffari@semnan.ac.ir
Ahmad
Alinejad
Semnan University
alinejad34br@yahoo.com
Let $A$ be an arbitrary Banach algebra and $varphi$ a homomorphism from $A$ onto $Bbb C$. Our first purpose in this paper is to give some equivalent conditions under which guarantees a $varphi$-mean of norm one. Then we find some conditions under which there exists a $varphi$-mean in the weak$^*$ cluster of ${ain A; |a|=varphi(a)=1}$ in $A^{**}$.
Amenability,Banach algebras,$F$-algebra,$varphi$-amenability,$varphi$-mean
http://bims.iranjournals.ir/article_237.html
http://bims.iranjournals.ir/article_237_2d7117eadedb5265aee5e2e415a2034f.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
The coefficients of differentiated expansions of double and triple Jacobi polynomials
739
765
EN
Eid
Doha
Cairo University-Faculty of Science-Mathematics Department
eiddoha@frcu.eun.eg
Waleed
Mohammed
Abd-Elhameed
Cairo University-Faculty of Science-Mathematics Department
walee_9@yahoo.com
Hany
Ahmed
Helwan University-Faculty of Science-Mathematics Department
hany_195@frcu.eun.eg
Formulae expressing explicitly the coefficients of an expansion of double Jacobi polynomials which has been partially differentiated an arbitrary number of times with respect to its variables in terms of the coefficients of the original expansion are stated and proved. Extension to expansion of triple Jacobi polynomials is given. The results for the special cases of double and triple ultraspherical polynomials are considered. Also the results for Chebyshev polynomials of the first, second, third and fourth kinds and of Legendre polynomials are noted. An application of how to use double Jacobi polynomials for solving Poisson’s equation in two variables subject to nonhomogeneous mixed boundary conditions is described.
Jacobi polynomials,spectral methods,hypergeometric series, Poisson’s
equation
http://bims.iranjournals.ir/article_238.html
http://bims.iranjournals.ir/article_238_bf9ba54f7aca429e3d30f958160c42bc.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
Superlinearly convergent exact penalty projected structured Hessian updating schemes for constrained nonlinear least squares: asymptotic analysis
767
786
EN
N.
Mahdavi-Amiri
Sharif University of Technology
nezamm@sharif.edu
Mohammad Reza
Ansari
Sharif University of Technology
ansari.mr@gmail.com
We present a structured algorithm for solving constrained nonlinear least squares problems, and establish its local two-step Q-superlinear convergence. The approach is based on an adaptive structured scheme due to Mahdavi-Amiri and Bartels of the exact penalty method of Coleman and Conn for nonlinearly constrained optimization problems. The structured adaptation also makes use of the ideas of Nocedal and Overton for handling the quasi-Newton updates of projected Hessians. We discuss the comparative results of the testing of our programs and three nonlinear programming codes from KNITRO on some randomly generated test problems due to Bartels and Mahdavi-Amiri. The results indeed confirm the practical significance of our special considerations for the inherent structure of the least squares.
Constrained nonlinear programming,exact penalty method,nonlinear least squares,projected structured Hessian update
http://bims.iranjournals.ir/article_240.html
http://bims.iranjournals.ir/article_240_962ced196e74eb319a889a7deb02eb7c.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
Improved infeasible-interior-point algorithm for linear complementarity problems
787
803
EN
Maryam
Zangiabadi
Dept. Appied Mathematics,
Shahrekord University
zangiabadi@sci.sku.ac.ir
Hossein
Mansouri
Dept. Applied Mathematics, Shahrekord University
mansouri@sci.sku.ac.ir
We present a modified version of the infeasible-interior- We present a modified version of the infeasible-interior-point algorithm for monotone linear complementary problems introduced by Mansouri et al. (Nonlinear Anal. Real World Appl. 12(2011) 545--561). Each main step of the algorithm consists of a feasibility step and several centering steps. We use a different feasibility step, which targets at the $mu^+$-center. It results a better iteration bound.
linear complementarity problems,interior-point methods,polynomial complexity,full-Newton steps,search directions
http://bims.iranjournals.ir/article_241.html
http://bims.iranjournals.ir/article_241_161c4ab48ed9b2e646af66d31fcd932d.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
Metric and periodic lines in the Poincare ball model of hyperbolic geometry
805
815
EN
Oğuzhan
Demirel
Afyon Kocatepe University
Faculty of Science and Arts
ANS Campus
odemirel@aku.edu.tr
Emine
Soyturk Seyrantepe
Afyon Kocatepe University
Faculty of Science and Arts
soyturk@aku.edu.tr
N.
Sonmez
Afyon Kocatepe University Faculty of Science and Arts
nceylan@aku.edu.tr
In this paper, we prove that every metric line in the Poincare ball model of hyperbolic geometry is exactly a classical line of itself. We also proved nonexistence of periodic lines in the Poincare ball model of hyperbolic geometry.
Metric spaces,Poincare ball model,hyperbolic geometry
http://bims.iranjournals.ir/article_242.html
http://bims.iranjournals.ir/article_242_44e4e1fc911f68b5a8f2e6d83dc55e4a.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
Compact weighted Frobenius-Perron operators and their spectra
817
826
EN
Mohammad Reza
Jabbarzadeh
faculty of mathematical sciences, university of tabriz
mrjabbar11@yahoo.com
Hossain
Emamalipour
faculty of mathematical sciences, university of tabriz, p. o. box: 51664
hemamali@yahoo.com
In this note we characterize the compact weighted Frobenius-Perron operator $p$ on $L^1(Sigma)$ and determine their spectra. We also show that every weakly compact weighted Frobenius-Perron operator on $L^1(Sigma)$ is compact.
Frobenius-perron operator,weighted composition
operator,conditional expectation
http://bims.iranjournals.ir/article_243.html
http://bims.iranjournals.ir/article_243_8a0cae2a4c335660f929d5a7e98d80d4.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
Error bounds in approximating n-time differentiable functions of self-adjoint operators in Hilbert spaces via a Taylor's type expansion
827
842
EN
Silvestru
Sever
Dragomir
Mathematics, School of Engineering & Science, Victoria University, PO Box 14428,
Melbourne, Australia
sever.dragomir@vu.edu.au
On utilizing the spectral representation of selfadjoint operators in Hilbert spaces, some error bounds in approximating $n$-time differentiable functions of selfadjoint operators in Hilbert Spaces via a Taylor's type expansion are given.
Selfadjoint operators,Functions of Selfadjoint operators,Spectral representation,Inequalities for selfadjoint operators
http://bims.iranjournals.ir/article_245.html
http://bims.iranjournals.ir/article_245_73a8e6efb747727fb3f26520ccd854dd.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
38
3
2012
09
15
Complete convergence of moving-average processes under negative
dependence sub-Gaussian assumptions
843
852
EN
Mohammad
Amini
Ferdowsi University of Mashhad
m-amini@um.ac.ir
Hamid Reza
Nili Sani
University of Birjand
nilisani@yahoo.com
Abolghasem
Bozorgnia
Ferdowsi University of Mashhad
bozorgnia@um.ac.ir
The complete convergence is investigated for moving-average processes of doubly infinite sequence of negative dependence sub-gaussian random variables with zero means, finite variances and absolutely summable coefficients. As a corollary, the rate of complete convergence is obtained under some suitable conditions on the coefficients.
Moving-average processes,Complete
convergence,Negative dependence,sub-gaussian random variables
http://bims.iranjournals.ir/article_247.html
http://bims.iranjournals.ir/article_247_87efc66f7c6b9c43675f18a89e45be94.pdf