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 <br /> <br />f(f(x)-f(y))=f(x+y)+f(x-y)-f(x)-f(y) <br /> <br /> 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.<br />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: <br />In the present paper, we give a necessary and sufficient condition <br />for contact CR-warped product to be contact CR-product in Kenmotsu <br />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 <br />of three step random iterative scheme with errors to common random fixed points of three asymptotically <br />nonexpansive nonself random mappings in a real uniformly convex separable Banach space. <br />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 <br />bitopological spaces and obtain some results. Further, we also <br />study the pairwise weakly Lindelof subspaces and subsets, and <br />investigate some of their properties. It was proved that a <br />pairwise weakly Lindelof property is not a hereditary <br />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. <br /> In this paper, we study the notions of nilpotent and solvable polygroups by using the notion of heart of polygroups. In particular, we give <br /> 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 <br />p , then the projective special linear group PSL(2, q) and the stabilizer <br />of a point of the projective line have maximum sum element <br />orders among all proper subgroups of projective general linear <br />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 of<br />a Banach algebra A, where ph is a continuous homomorphism on A.<br />We prove that if ph is a continuous epimorphism on A and A has<br />a bounded approximate identity and A is ph- bi<br />at, then A is ph-amenable. In the case where ph is an isomorphism on A we show<br />that the ph- amenability of A implies its ph-bi<br />atness.
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.<br />We say that a group G has n centralizers (G is a Cn-group) if |C(G)| = n.<br />In this note, we prove that every ﬁnite Cn-group with n ≤ 21 is soluble and<br />this estimate is sharp. Moreover, we prove that every ﬁnite Cn-group with<br />|G| < 30n+15<br />19 is non-nilpotent soluble. This result gives a partial answer to a<br />conjecture 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 to<br />include designs where there is more than one criteria is used in<br />deciding on the allocation of additional sampling effort. These<br />criteria, or conditions, can be a measure of the target<br />population, or a measure of some related population. We develop<br />Murthy estimator for the design that is unbiased estimators for<br />the population mean, and propose another, more efficient,<br />estimator. We investigate asymptotic properties of this estimator.<br />We use a simulation study to investigate design properties of the<br />multi-criteria adaptive sequential sampling scheme and also some<br />estimator 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 Banach<br />algebras 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<br />$A^2$ is Hermitian. Also, we consider normal matrices $A in M_n$ whose $k^{th}$ power are semidefinite. For such matrices<br />we 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 <br />a in R is said to be r-clean if a = e+r, where e is an idempotent and <br />r is a regular (von Neumann) element in R. If every element of R is <br />r-clean, then R is called an r-clean ring. In this paper, we prove that <br />the concepts of clean ring and r-clean ring are equivalent for abelian <br />rings. Further we prove that if 0 and 1 are the only idempotents <br />in R, then an r-clean ring is an exchange ring. Also we show that <br />the center of an r-clean ring is not necessary r-clean, but if 0 and <br />1 are the only idempotents in R, then the center of an r-clean ring <br />is r-clean. Finally we give some properties and examples of r-clean <br />rings
http://bims.iranjournals.ir/article_432_9133bb4819dd6ac2221c6ba470843a82.pdf
clean ring
exchange ring
r-clean ring
von Neumann regular ring