eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
383
403
418
Hyers-Ulam-Rassias stability of a composite
functional equation in various normed spaces
H. Azadi Kenary
azadi@mail.yu.ac.ir
1
Yasouj University
In this paper, we prove the generalized Hyers-Ulam(or Hyers-Ulam-Rassias ) stability of the following composite functional equation f(f(x)-f(y))=f(x+y)+f(x-y)-f(x)-f(y) in various normed spaces.
http://bims.iranjournals.ir/article_418_aed1e9f7f9878d1f0b43d5533e3a8583.pdf
Generalized Hyers-Ulam stability
random normed space
non-Archimedean normed spaces
fixed point method
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
405
413
419
A note on superspecial and maximal curves
A. Kazemifard
kazemifard.ahmad@stu.sku.ac.ir
1
A. Naghipour
naghipour@stu.ac.ir
2
S. Tafazolian
tafazolian@gmail.com
3
Shahrekord University
Shahrekord University
Institute for Advanced Studies in Basic Sciences
In this note we review a simple criterion, due to Ekedahl, for superspecial curves defined over finite fields.Using this we generalize and give some simple proofs for some well-known superspecial curves.
http://bims.iranjournals.ir/article_419_6a4faa2252a2fb3c19cfbeaa4eca5fa5.pdf
Cartier operator
Supersingular curves
finite fields
maximal curves
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
415
429
420
Contact CR-Warped product submanifolds in Kenmotsu space forms
M. Atceken
mehmet.atceken@gop.edu.tr
1
Gaziosmanpasa University, Faculty of Arts and Sciences, Department of Mathematics, 60250 Tokat/TURKEY
Abstract: In the present paper, we give a necessary and sufficient condition for contact CR-warped product to be contact CR-product in Kenmotsu space forms.
http://bims.iranjournals.ir/article_420_56f4f671492858923dbce165596202a3.pdf
Kenmotsu space form
Contact CR-warped product
Contact CR-product
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
431
453
421
On the convergence of three-step random iterative procesess with errors
of nonself asymptotically nonexpansive random
mappings
R. Rashwan
rr_rashwan54@yahoo.com
1
D. Al-Baqeri
baqeri$_$27@yahoo.com
2
Department of Mathematics, University of Assiut, P.O.Box 71516, Assiut, Egypt
Department of Mathematics, University of Assiut, P.O.Box 71516, Assiut, Egypt
begin{abstract} In this paper, we prove some strong and weak convergence of three step random iterative scheme with errors to common random fixed points of three asymptotically nonexpansive nonself random mappings in a real uniformly convex separable Banach space. end{abstract}
http://bims.iranjournals.ir/article_421_aa474a911e5779057293406860aac8c4.pdf
Asymptotically nonexpansive nonself random mapping
Weak and strong convergence
Common random fixed points
Completely continuous
Opial's condition
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
455
467
422
Localization operators on homogeneous spaces
R. Kamyabi Gol
kamyabi@ferdowsi.um.ac.ir
1
F. Esmaeelzadeh
esmaeelzadeh@alumni.um.ac.ir
2
R. Raisi Tousi
raisi@ferdowsi.um.ac.ir
3
Ferdowsi University of Mashhad
Ferdowsi University of Mashhad
Ferdowsi University of Mashhad
Let $G$ be a locally compact group, $H$ be a compact subgroup of $G$ and $varpi$ be a representation of the homogeneous space $G/H$ on a Hilbert space $mathcal H$. For $psi in L^p(G/H), 1leq p leqinfty$, and an admissible wavelet $zeta$ for $varpi$, we define the localization operator $L_{psi,zeta} $ on $mathcal H$ and we show that it is a bounded operator. Moreover, we prove that the localization operator is in Schatten $p$-class and also it is a compact operator for $ 1leq p leqinfty$.
http://bims.iranjournals.ir/article_422_8480c0250cbcd89dcc3dc2b6983c19d5.pdf
Homogenous space
square integrable representation
n localization operator
Schatten $p$-class operator
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
469
485
423
On pairwise weakly Lindelof bitopological spaces
A. Kilicman
akilic@upm.edu.my
1
Z. Salleh
zabidin@umt.edu.my
2
University Putra Malaysia
University Malaysia Terengganu
In the present paper we introduce and study the notion of pairwise weakly Lindelof bitopological spaces and obtain some results. Further, we also study the pairwise weakly Lindelof subspaces and subsets, and investigate some of their properties. It was proved that a pairwise weakly Lindelof property is not a hereditary property.
http://bims.iranjournals.ir/article_423_9d5d1804ff1eebe8d009877fcc795014.pdf
bitopological space
ij-weakly Lindelof
pairwise
weakly Lindelof
ij-weakly Lindelof relative
ij-regular open and ij-regular closed
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
487
499
424
On nilpotent and solvable polygroups
H. Aghabozorgi
h_aghabozorgi1@yahoo.com
1
M. Jafarpour
m.j@mail.vru.ac.ir
2
B. Davvaz
davvaz@yazduni.ac.ir
3
Department of Mathematics, Yazd University, Yazd, Iran
Department of Mathematics, Vali-e-Asr University, Rafsanjan, Iran
Yazd University
Applications of hypergroups have mainly appeared in special subclasses. One of the important subclasses is the class of polygroups. In this paper, we study the notions of nilpotent and solvable polygroups by using the notion of heart of polygroups. In particular, we give a necessary and sufficient condition between nilpotent (solvable) polygroups and fundamental groups.
http://bims.iranjournals.ir/article_424_1382aa8542282fb58e8f5814d16a8370.pdf
(semi)hypergroup
polygroup
derived polygroup
nilpotent
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
501
505
425
Maximum sum element orders of all proper subgroups of
PGL(2, q)
S. Jafarian Amri
sm_jafarian@znu.ac.ir
1
Zanjan University
In this paper we show that if q is a power of a prime p , then the projective special linear group PSL(2, q) and the stabilizer of a point of the projective line have maximum sum element orders among all proper subgroups of projective general linear group PGL(2, q) for q odd and even respectively
http://bims.iranjournals.ir/article_425_131e9bcb13643b18ecd70f5a42b54a7b.pdf
linear groups
maximal subgroups
element order
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
507
515
426
phi-Amenable and phi-biflat Banach algebras
Z. Ghorbani
ghorbani@sci.ui.ac.ir
1
M. Lashkarizadeh Bami
lashkari@sci.ui.ac.ir
2
Depertment of Mathematics-University of Isfahan
Department of Mathematics, University of Isfahan
In this paper we study the concept of ph-biatness ofa Banach algebra A, where ph is a continuous homomorphism on A.We prove that if ph is a continuous epimorphism on A and A hasa bounded approximate identity and A is ph- biat, then A is ph-amenable. In the case where ph is an isomorphism on A we showthat the ph- amenability of A implies its ph-biatness.
http://bims.iranjournals.ir/article_426_7cc478cf8c3e322dd9f487c878ba4cfc.pdf
Banach algebra
ph-biat
ph-amenable
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
517
521
427
On solubility of groups with finitely many centralizers
M. Zarrin
zarrin78@gmail.com
1
University of Kurdistan
For any group G, let C(G) denote the set of centralizers of G.We say that a group G has n centralizers (G is a Cn-group) if |C(G)| = n.In this note, we prove that every ﬁnite Cn-group with n ≤ 21 is soluble andthis estimate is sharp. Moreover, we prove that every ﬁnite Cn-group with|G| < 30n+1519 is non-nilpotent soluble. This result gives a partial answer to aconjecture raised by A. Ashraﬁ in 2000
http://bims.iranjournals.ir/article_427_8d03882cd4079696032e9bedcf5e7396.pdf
centralizer
n-centralizer group
soluble group
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
523
528
428
Completely coretractable rings
J. Zemlicka
zemlicka@karlin.mff.cuni.cz
1
Department of Algebra Faculty of Mathematics and Physics, Charles University in Prague,
A module $M$ is said to be coretractable if there exists a nonzero homomorphism of every nonzero factor of $M$ into $M$. We prove that all right (left) modules over a ring are coretractable if and only if the ring is Morita equivalent to a finite product of local right and left perfect rings.
http://bims.iranjournals.ir/article_428_5da7b8715fe169e19d3b38146e66c250.pdf
coretractable module
retractable module
Kash ring
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
529
557
429
Asymptotic properties of the sample mean in adaptive sequential sampling with multiple selection criteria
A. Parvardeh
a.parvardeh@sci.ui.ac.ir
1
B. Panahbehagh
bardia_p@math.iut.ac.ir
2
M. Salehi
salehi@qu.edu.qa
3
J. Brown
j.brown@math.canterbury.ac.nz
4
D. Smith
drsmith@usgs.gov
5
Academic Professor
Isfahan University of Technology
Qatar University
University of Canterbury
U.S. Geological Survey
We extend the method of adaptive two-stage sequential sampling toinclude designs where there is more than one criteria is used indeciding on the allocation of additional sampling effort. Thesecriteria, or conditions, can be a measure of the targetpopulation, or a measure of some related population. We developMurthy estimator for the design that is unbiased estimators forthe population mean, and propose another, more efficient,estimator. We investigate asymptotic properties of this estimator.We use a simulation study to investigate design properties of themulti-criteria adaptive sequential sampling scheme and also someestimator properties under the design.
http://bims.iranjournals.ir/article_429_0d7fda83d0d219c63685429b4eeea04c.pdf
Stratified sampling
Adaptive
two-stage sequential sampling
Asymptotic properties in finite
population
Consistency
Rare population
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
559
568
430
Biflatness and biprojectivity of Lau product of Banach algebras
A. Khoddami
khoddami-alireza@yahoo.com
1
H. Ebrahimi Vishki
vishki@ferdowsi.um.ac.ir
2
Ferdowsi University of Mashhad
Ferdowsi University of Mashhad
Amonge other things we give sufficient and necessary conditions for the Lau product of Banachalgebras to be biflat or biprojective.
http://bims.iranjournals.ir/article_430_ce7376069c17575dc6d19eeb2e34a06b.pdf
bimodule map
$theta$-Lau product
Tensor product
biflat
biprojective
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
569
578
431
Some results on the polynomial numerical hulls of matrices
H. Afshin
hamidrezaafshin@yahoo.com
1
M. Mehrjoofard
aahaay@gmail.com
2
A. Salemi
salemi@uk.ac.ir
3
Department of Mathematics, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran.
Department of Mathematics, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran.
Department of Mathematics, Shahid Bahonar University of Kerman, Kerman, Iran.
In this note we characterize polynomial numerical hulls of matrices $A in M_n$ such that$A^2$ is Hermitian. Also, we consider normal matrices $A in M_n$ whose $k^{th}$ power are semidefinite. For such matriceswe show that $V^k(A)=sigma(A)$.
http://bims.iranjournals.ir/article_431_3ccef3d5fa00a8a7178d1329d9bbcfd6.pdf
polynomial numerical hull
joint numerical range
normal matrices
eng
Iranian Mathematical Society (IMS)
Bulletin of the Iranian Mathematical Society
1017-060X
1735-8515
2013-07-01
39
3
579
588
432
Rings in which elements are the sum of an
idempotent and a regular element
N. Ashrafi
ashrafi49@yahoo.com
1
E. Nasibi
ebrahimnasibi@yahoo.com
2
Semnan University
Semnan University
Let R be an associative ring with unity. An element a in R is said to be r-clean if a = e+r, where e is an idempotent and r is a regular (von Neumann) element in R. If every element of R is r-clean, then R is called an r-clean ring. In this paper, we prove that the concepts of clean ring and r-clean ring are equivalent for abelian rings. Further we prove that if 0 and 1 are the only idempotents in R, then an r-clean ring is an exchange ring. Also we show that the center of an r-clean ring is not necessary r-clean, but if 0 and 1 are the only idempotents in R, then the center of an r-clean ring is r-clean. Finally we give some properties and examples of r-clean rings
http://bims.iranjournals.ir/article_432_9133bb4819dd6ac2221c6ba470843a82.pdf
clean ring
exchange ring
r-clean ring
von Neumann regular ring