Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
The stability of the solution of an inverse spectral problem with a singularity
1061
1070
EN
S.
Mosazadeh
Department of Pure Mathematics, Faculty of Mathematical Sciences, University of Kashan, Kashan, Iran
s.mosazadeh@kashanu.ac.ir
This paper deals with the singular Sturm-Liouville expressions <br />$ <br />ell y = -y''+q(x)y=lambda y <br />$ <br />on a finite interval, where the potential function $q$ is real and <br />has a singularity inside the interval. <br />Using the asymptotic estimates of a <br />spectral fundamental system of solutions of Sturm-Liouville <br />equation, the asymptotic form of the solution of the <br />equation (0.1) and the eigenvalues are obtained, and proves the stability of the <br />solution of the inverse spectral problem.
Sturm-Liouville,singularity,stability,boundary
value problem,inverse spectral problem
http://bims.iranjournals.ir/article_673.html
http://bims.iranjournals.ir/article_673_9e3d491594023542123a64783d14393b.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
Zero sets in pointfree topology and strongly $z$-ideals
1071
1084
EN
A. A.
Estaji
Faculty of Mathematics and Computer Sciences, Hakim Sabzevari University, Sabzevar, Iran.
aaestaji@hsu.ac.ir
A.
Karimi Feizabadi
Department of Mathematics, Gorgan Branch, Islamic Azad University, Gorgan, Iran.
akarimi@gorganiau.ac.ir
M.
Abedi
Faculty of Mathematics and Computer Sciences, Hakim Sabzevari University, Sabzevar, Iran.
abedi@esfarayen.ac.ir
In this paper a particular case of z-ideals, called strongly z-ideal, is defined by introducing zero sets in pointfree topology. We study strongly z-ideals, their relation with z-ideals and the role of spatiality in this relation. For strongly z-ideals, we analyze prime ideals using the concept of zero sets. Moreover, it is proven that the intersection of all zero sets of a prime ideal of C(L), which is ring of real-valued continuous functions for frame L, does not have more than one element. Also, z-filters are introduced in terms of pointfree topology. Then the relationship between z-filters and ideals, particularly maximal ideals, is examined. Finally, it is shown that the family of all zero sets is a base for the collection of closed sets.
Frame,ring of real-valued continuous
functions,zero set,$z$-ideal,strongly $z$-ideal
http://bims.iranjournals.ir/article_674.html
http://bims.iranjournals.ir/article_674_3f6d2ac9d9b3a090bc73c24dce7a7c62.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
Some concavity properties for general integral operators
1085
1092
EN
M.
Darus
School of Mathematical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi
Selangor DE, Malaysia
maslina@ukm.my
I.
Aldawish
School of Mathematical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi
Selangor DE, Malaysia
ibtisamaldawish@gmail.com
R. W.
Ibrahim
Institute of Mathematical Sciences, Universiti Malaya, 50603, Malaysia.
rabhaibrahim@yahoo.com
Let $C_0(alpha)$ denote the class of concave univalent functions defined in the open unit disk $mathbb{D}$. Each function $f in C_{0}(alpha)$ maps the unit disk $mathbb{D}$ onto the complement of an unbounded convex set. In this paper, we study the mapping properties of this class under integral operators.
Unit disk,univalent function,concave function,integral operator
http://bims.iranjournals.ir/article_675.html
http://bims.iranjournals.ir/article_675_ece62f5acf56020a260689a55dc1a3c7.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
On dimensions of derived algebra and central factor of a Lie algebra
1093
1102
EN
H.
Arabyani
Mashhad Branch, Islamic Azad University, Mashhad, Iran.
arabyani_h@yahoo.com
F.
Saeedi
Mashhad Branch, Islamic Azad University, Mashhad, Iran.
saeedi@mshdiau.ac.ir
Some Lie algebra analogues of Schur's theorem and its converses <br />are presented. As a result, it is shown that for a capable Lie algebra L we <br />always have dim L=Z(L) 2(dim(L2))2. We also give give some examples sup- <br />porting our results.
Capable Lie algebra,minimal generator,derived algebra,central factor
http://bims.iranjournals.ir/article_676.html
http://bims.iranjournals.ir/article_676_3da7c8c3cba5c1fff10c3774678d395f.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
Faber polynomial coefficient estimates for bi-univalent functions defined by subordinations
1103
1119
EN
S. G.
Hamidi
Department of Mathematics, Brigham Young University, Provo, Utah,
U.S.A.
s.hamidi_61@yahoo.com
J. M.
Jahangiri
Kent State University
jjahangi@kent.edu
A function is said to be bi-univalent on the open unit disk D if both the function and its inverse are univalent in D. Not much is known about the behavior of the classes of bi-univalent functions let alone about their coefficients. In this paper we use the Faber polynomial expansions to find coefficient estimates for four well-known classes of bi-univalent functions which are defined by subordinations. Both the coefficient bounds and the techniques presented are new and we hope that this paper will inspire future researchers in applying our approach to other related problems.
faber polynomials,bi-univalent,subordinations
http://bims.iranjournals.ir/article_677.html
http://bims.iranjournals.ir/article_677_e5131ddd5a6ee9375c73e35f78d96727.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
Entire functions sharing a small entire function with their difference operators
1121
1129
EN
J.
Zhang
College of Science,
China University of Mining and Technology, Xuzhou 221116, PR
China
zhangjie1981@cumt.edu.cn
H. Y.
Kang
College of Science,
China University of Mining and Technology, Xuzhou 221116, PR
China
haiyankang@cumt.edu.cn
L. W.
Liao
Department of Mathematics, Nanjing University, Nanjing 210093, PR
China
maliao@nju.edu.cn
In this paper, we mainly investigate the uniqueness of the entire function sharing a <br />small entire function with its high difference operators. We obtain <br />one results, which can give a negative answer to an uniqueness question <br />relate to the Bruck conjecture dealt by Liu and Yang. Meanwhile, we also establish a difference analogue of the <br />Bruck conjecture for entire functions of order less than 2, which improves some results obtained by Liu and Yang.
Entire function,difference equation,small function
http://bims.iranjournals.ir/article_678.html
http://bims.iranjournals.ir/article_678_f173efbc4f3bdd34d7f205f1b5caf94a.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
New conditions on ground state solutions for Hamiltonian elliptic systems with gradient terms
1131
1146
EN
F. F.
Liao
School of Mathematics and Statistics Central South University Changsha, 410083, Hunan \newline Department of Mathematics, Xiangnan University, Chenzhou, 423000, Hunan, P.R. China
liaofangfang1981@126.com
X. H.
Tang
School of Mathematics and Statistics Central South University Changsha, 410083, Hunan, P.R. China
tangxh@mail.csu.edu.cn
D. D.
Qin
School of Mathematics and Statistics Central South University Changsha, 410083, Hunan, P.R. China
qindd132@163.com
This paper is concerned with the following elliptic system:<br />$$<br /> left{<br /> begin{array}{ll}<br /> -triangle u + b(x)nabla u + V(x)u=g(x, v), <br /> -triangle v - b(x)nabla v + V(x)v=f(x, u), <br /> end{array}<br /> right.<br /> $$<br /> for $x in {R}^{N}$, where $V $, $b$ and $W$ are 1-periodic in $x$, and $f(x,t)$, $g(x,t)$ are super-quadratic. In this paper, we give a new technique to show the boundedness of Cerami sequences and establish the existence of ground state solutions with mild assumptions on $f$ and $g$.
Hamiltonian elliptic system,superlinear,ground state solutions,strongly indefinite functionals
http://bims.iranjournals.ir/article_679.html
http://bims.iranjournals.ir/article_679_372071dc741478798df76bfd0df0b3cd.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
Random approximation of a general symmetric equation
1147
1159
EN
H.
Rezaei
Department of
Mathematics, University
of Yasouj, P.O. Box 75914-74831, Yasouj, Iran
rezaei@mail.yu.ac.ir
C.
Park
Department of
Mathematics, Research Institute for Natural Sciences, University
of Hanyang, P.O. Box 133-791, Seoul, Korea
baak@hanyang.ac.kr
In this paper, we prove the Hyers-Ulam stability of the symmetric functional<br />equation $f(ph_1(x,y))=ph_2(f(x), f(y))$ in random normed spaces. As a consequence, we<br />obtain some random stability results in the sense of Hyers-Ulam-Rassias.
Hyers-Ulam stability,general symmetric equation,random normed space
http://bims.iranjournals.ir/article_680.html
http://bims.iranjournals.ir/article_680_0d027ec6397c61cc337361620f39c153.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
Some approximate fixed point results for proximinal valued $beta$-contractive multifunctions
1161
1172
EN
M. A.
Miandaragh
Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, Iran
mehdi59ir@yahoo.com
A.
Pitea
Department of Mathematics, University Politehnica of Bucharest, Bucharest, Romania
arianapitea@yahoo.com
Sh.
Rezapour
Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, Iran
sh.rezapour@azaruniv.edu
In this paper, we prove some approximate fixed point results for proximinal valued $beta$-contractive multifunctions on metric spaces. We show that our results generalize some old fixed point results in the literature.
$\beta$-contractive multifunction,approximate fixed point,proximinal,fixed point
http://bims.iranjournals.ir/article_681.html
http://bims.iranjournals.ir/article_681_1b2286e1c66522fe865913deee6bec6d.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
On properties of dependent general progressively type-II censored order statistics
1173
1182
EN
M.
Rezapour
Department of Statistics. Faculty of Mathematics and Computer, Shahid Bahonar University of Kerman, Kerman, Iran
mohsenrzp@gmail.com
M. H.
Alamatsaz
Department of Statistics, University of Isfahan,Isfahan, Iran \newline
Naghshejahan Institute of Higher Education, Baharestan, Isfahan, Iran
alamatho@sci.ui.ac.ir
In the literature of life-testing, general progressive censoring has been studied extensively. But, all the results have been developed under the key assumption that the units under<br />test are independently distributed. In this paper, we study general progressively Type-II censored order statistics arising from identical units under test which are jointly distributed according to an Archimedean copula with completely monotone generator (GPCOSARCM-II). Density, distribution and joint density functions of GPCOSARCM-II are all derived. Finally, some examples of GPCOSARCM-II are provided.
Stochastic ordering,Archimedean copula,order statistics,general progressive censoring,reliability systems
http://bims.iranjournals.ir/article_682.html
http://bims.iranjournals.ir/article_682_a432686abd7f287dfc602ed35e2606ef.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
On Sandwich theorems for certain classes of analytic functions
1183
1193
EN
R.
Aghalary
Department of Mathematics, Faculty of Science, Urmia University, Urmia, Iran
raghalary@yahoo.com
A.
Ebadian
Department of Mathematics, Faculty of Science, Urmia University, Urmia, Iran
a.ebadian@urmai.ac.ir
M.
Mafakheri
Department of Mathematics, Faculty of Science, Urmia University, Urmia, Iran
m.mafakheri85@yahoo.com
The purpose of this present paper is to derive some subordination and superordination results for certain analytic functions in the open unit disk. <br />Relevant connections of the results, which are presented in the paper, with various known results are also considered.
Subordination,superordination,integral operators,Hadamard product
http://bims.iranjournals.ir/article_683.html
http://bims.iranjournals.ir/article_683_35ce3e09e9943be0669ec43da1319871.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
A note on critical point and blow-up rates for singular and degenerate parabolic equations
1195
1205
EN
B.
Liu
College of Science, China University of Petroleum, Qingdao 266580, Shandong Province, P.R. China
bcliu@aliyun.com
F.
Li
College of Science, China University of PetroleumCollege of Science, China University of Petroleum, Qingdao 266580, Shandong Province, P.R. China
fjli@upc.edu.cn
In this paper, we consider singular and degenerate parabolic equations<br />$$<br />u_t =(x^alpha u_x)_x +u^m (x_0,t)v^{n} (x_0,t),quad<br />v_t =(x^beta v_x)_x +u^q (x_0,t)v^{p} (x_0,t),$$ in $(0,a)times (0,T)$, subject to null<br />Dirichlet boundary conditions, where $m,n, p,qge 0$, $alpha, betain [0,2)$ and $x_0in (0,a)$. The optimal classification of non-simultaneous and simultaneous blow-up solutions is determined. Additionally, we obtain blow-up rates and sets for the solutions. The singular rates for the derivation of the solutions are given.
singular and degenerate parabolic equations,blow-up classification,simultaneous blow-up rates
http://bims.iranjournals.ir/article_684.html
http://bims.iranjournals.ir/article_684_61771b8a5c6442802437ee788e2c3fce.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
Automatic continuity of surjective $n$-homomorphisms on Banach algebras
1207
1211
EN
M.
Eshaghi Gordji
Department of Mathematics, Semnan University, P. O. Box 35195-363, Semnan, Iran, and,
Center of Excellence in Nonlinear Analysis and Applications (CENAA), Semnan University, Iran
madjid.eshaghi@gmail.com
A.
Jabbari
Young Researchers and Elite Club, Ardabil Branch, Islamic Azad University, Ardabil, Iran
jabbari_al@yahoo.com
E.
Karapinar
Department of Mathematics, Atilim University, 06836, Incek, Ankara, Turkey
ekarapinar@atilim.edu.tr
In this paper, we show that every surjective $n$-homomorphism ($n$-anti-homomorphism) from a Banach algebra $A$ into a semisimple Banach algebra $B$ is continuous.
Banach algebra,$n$-homomorphism,semisimple algebra
http://bims.iranjournals.ir/article_685.html
http://bims.iranjournals.ir/article_685_102e171d4b2c18e7c75b1a1ba7261d14.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
Approximation of an additive mapping in various normed spaces
1213
1233
EN
M. S.
Shiri
Department of Mathematics, Arsanjan Branch, Islamic Azad University, Arsanjan,
Iran.
m.s.shiri@gmail.com
H.
Azadi Kenary
Department of Mathematics, College of Sciences, Yasouj University, Yasouj 75918-74831,
Iran.
azadi@mail.yu.ac.ir
In this paper, using the fixed point and direct methods, we prove the generalized Hyers-Ulam-Rassias stability <br />of the following Cauchy-Jensen additive functional equation: <br />begin{equation}label{main} <br />fleft(frac{x+y+z}{2}right)+fleft(frac{x-y+z}{2}right)=f(x)+f(z)end{equation} <br />in various normed spaces. <br />The concept of Hyers-Ulam-Rassias stability originated from Th. M. <br />Rassias’ stability theorem that appeared in his paper: On the <br />stability of the linear mapping in Banach spaces, Proc. Amer. <br />Math. Soc. 72 (1978), 297-300.
Hyers-Ulam-Rassias stability,non-Archimedean normed spaces,random normed spaces
http://bims.iranjournals.ir/article_686.html
http://bims.iranjournals.ir/article_686_ef1ccfb37f5b6e7b4200e921fa0b1fdd.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
A hybrid method for singularly perturbed delay boundary value problems exhibiting a right boundary layer
1235
1247
EN
F. Z.
Geng
Department of Mathematics, Changshu Institute of Technology,
Changshu, Jiangsu 215500, China
gengfazhan@sina.com
S. P.
Qian
Department of Mathematics, Changshu Institute of Technology,
Changshu, Jiangsu 215500, China
qsp3@cslg.cn
The aim of this paper is to present a numerical method for singularly perturbed convection-diffusion problems with a delay. The method is a combination of the asymptotic expansion technique and the reproducing kernel method (RKM). First an asymptotic expansion for the solution of the given singularly perturbed delayed boundary value problem is constructed. Then the reduced regular delayed differential equation is solved analytically using the RKM. An error estimate and two numerical examples are provided to illustrate the effectiveness of the present method. The results of numerical examples show that the present method is accurate and efficient.
Reproducing kernel method,singularly perturbed problems,delay boundary value problems
http://bims.iranjournals.ir/article_687.html
http://bims.iranjournals.ir/article_687_2d4a3117a1c61a52fba7f8ef99c06aa8.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
A relative extending module and torsion precovers
1249
1257
EN
M.
Kemal Berktas
Department of
Mathematics, Usak University, Usak, Turkey
mkb@usak.edu.tr
S.
Dogruoz
Department of
Mathematics, Adnan Menderes University, Aydin, Turkey
sdogruoz@adu.edu.tr
We first characterize $tau$-complemented modules with relative (pre)-covers. We also introduce an extending module relative to $tau$-pure submodules on a hereditary torsion theory $tau$ and give its relationship with $tau$-complemented modules.
$\tau$-pure submodule,extending module,torsion theory,(pre)covers,$\tau$-cocompact module
http://bims.iranjournals.ir/article_688.html
http://bims.iranjournals.ir/article_688_6e9d588573e58fc2ad8596db373dfa5f.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
A uniform approximation method to solve absolute value equation
1259
1269
EN
H.
Esmaeili
Department of
Mathematics, Bu-Ali Sina University, Hamedan, Iran
esmaeili47@yahoo.com
E.
Mahmoodabadi
Department of
Mathematics, Bu-Ali Sina University, Hamedan, Iran
mahmoodabadi@basu.ac.ir
M.
Ahmadi
Department of
Mathematics, Malayer University, Malayer, Iran
mehdi.math86@yahoo.com
In this paper, we propose a parametric uniform approximation method to solve NP-hard absolute value equations. <br />For this, we uniformly approximate absolute value in such a way that the nonsmooth absolute value equation can be <br />formulated as a smooth nonlinear equation. By solving the parametric smooth nonlinear equation using Newton method, for a decreasing sequence of parameters, we can get the solution of absolute value equation. It is proved that the method is globally convergent under some weaker conditions with respect to existing methods. <br />Moreover, preliminary numerical results indicate effectiveness and robustness of our method to solve absolute value equations.
Absolute value equation,Uniform approximation,Newton method
http://bims.iranjournals.ir/article_689.html
http://bims.iranjournals.ir/article_689_6b5fdd857f308ef88432bda7c9710f7f.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
On generalized reduced representations of restricted Lie superalgebras in prime characteristic
1271
1285
EN
Y. F.
Yao
Department of Mathematics, Shanghai Maritime University, Shanghai 201306, China
yfyao@shmtu.edu.cn
Y. Y.
Li
School of Fundamental Studies, Shanghai University of Engineering Science, Shanghai 201620, China
yiyang_li1979@aliyun.com
Let $mathbb{F}$ be an algebraically closed field of prime characteristic $p>2$ and $(g, [p])$ a finite-dimensional restricted Lie superalgebra over $mathbb{F}$. It is showed that any<br />finite-dimensional indecomposable $g$-module is a module for a finite-dimensional quotient of the universal enveloping superalgebra of $g$. These quotient superalgebras are called the generalized reduced enveloping superalgebras, which generalize the notion of reduced enveloping superalgebras. Properties and representations of these generalized reduced enveloping superalgebras are studied. Moreover, each such superalgebra can be identified as a reduced enveloping superalgebra of the associated restricted Lie superalgebra.
Restricted Lie superalgebra,generalized reduced
representation,indecomposable module,$p$-character,block
http://bims.iranjournals.ir/article_690.html
http://bims.iranjournals.ir/article_690_b7609c817d7a1f6ca7340a97dd274f0f.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
Hypersurfaces of a Sasakian space form with recurrent shape operator
1287
1297
EN
E.
Abedi
Department of
Mathematics, Azarbaijan Shahid Madani University, P.O. Box 53751 71379, Tabriz, Iran
esabedi@azaruniv.edu
M.
Ilmakchi
Department of
Mathematics, Azarbaijan Shahid Madani University, P.O. Box 53751 71379, Tabriz, Iran
mohammad_ilmakchi@yahoo.com
Let $(M^{2n},g)$ be a real hypersurface with recurrent shape<br />operator and tangent to the structure vector field $xi$ of the Sasakian space form<br />$widetilde{M}(c)$. We show that if the shape operator $A$ of $M$ is<br />recurrent then it is parallel. Moreover, we show that $M$<br />is locally a product of two constant $phi-$sectional curvature<br />spaces.
Recurrent hypersurfaces,Sasakian manifold
http://bims.iranjournals.ir/article_691.html
http://bims.iranjournals.ir/article_691_bc7b646fa536b7aef990872004888cf1.pdf
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
41
5
2015
10
01
On a class of Kirchhoff type systems with nonlinear boundary condition
1299
1313
EN
S. H.
Rasouli
Department of Mathematics, Faculty of Basic Sciences,
Babol University of Technology, Babol, Iran
s.h.rasouli@nit.ac.ir
H.
Norouzi
Department of Mathematics, Faculty of Basic Sciences,
Babol University of Technology, Babol, Iran
h.norouzi555@gmail.com
A class of Kirchhoff type systems with nonlinear boundary <br />conditions considered in this paper. By using the method of Nehari <br />manifold, it is proved that the system possesses two nontrivial <br />nonnegative solutions if the parameters are small enough.
Kirchhoff type systems,Nonlinear
boundary condition,Nehari manifold
http://bims.iranjournals.ir/article_692.html
http://bims.iranjournals.ir/article_692_19b0208133e50f394ec97856bcbc7c45.pdf