2019-01-21T14:26:29Z
http://bims.iranjournals.ir/?_action=export&rf=summon&issue=71
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
Bulletin of the Iranian Mathematical Society
2015
02
01
http://bims.iranjournals.ir/article_602_ab8ee796929d989020f1f0a5378c1aeb.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
Iterative algorithm for the generalized $(P,Q)$-reflexive solution of a quaternion matrix equation with $j$-conjugate of the unknowns
N.
Li
In the present paper, we propose an iterative algorithm for solving the generalized $(P,Q)$-reflexive solution of the quaternion matrix equation $overset{u}{underset{l=1}{sum}}A_{l}XB_{l}+overset{v} {underset{s=1}{sum}}C_{s}widetilde{X}D_{s}=F$. By this iterative algorithm, the solvability of the problem can be determined automatically. When the matrix equation is consistent over a generalized $(P,Q)$-reflexive matrix $X$, a generalized $(P,Q)$-reflexive solution can be obtained within finite iteration steps in the absence of roundoff errors, and the least Frobenius norm generalized $(P,Q)$-reflexive solution can be obtained by choosing an appropriate initial iterative matrix. Furthermore, the optimal approximate generalized $(P,Q)$-reflexive solution to a given matrix $X_{0}$ can be derived by finding the least Frobenius norm generalized $(P,Q)$-reflexive solution of a new corresponding quaternion matrix equation. Finally, two numerical examples are given to illustrate the efficiency of the proposed methods.
Quaternion matrix equation
generalized
$(P
Q)$-reflexive solution
iterative method
optimal approximate solution
2015
02
01
1
22
http://bims.iranjournals.ir/article_587_d3b1d745724dc512671e8aab4273eea4.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
On ideals of ideals in $C(X)$
F.
Azarpanah
A. R.
Olfati
In this article, we have characterized ideals in $C(X)$ in which every ideal is also an ideal (a $z$-ideal) of $C(X)$. Motivated by this characterization, we observe that $C_infty(X)$ is a regular ring if and only if every open locally compact $sigma$-compact subset of $X$ is finite. Concerning prime ideals, it is shown that the sum of every two prime (semiprime) ideals of each ideal in $C(X)$ is prime (semiprime) if and only if $X$ is an $F$-space. Concerning maximal ideals of an ideal, we generalize the notion of separability to ideals and we have proved the coincidence of separability of an ideal with dense separability of a subspace of $beta X$. Finally, we have shown that the Goldie dimension of an ideal $I$ in $C(X)$ coincide with the cellularity of $XsetminusDelta (I)$.
Dense separable
cellularity
$sigma$-compact
$F$-space
Goldie dimension
2015
02
01
23
41
http://bims.iranjournals.ir/article_588_8b401757cc747587b6c015c12346320e.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
The continuity of linear and sublinear correspondences defined on cones
M.
Aghajani
K.
Nourouzi
D.
ÓRegan
In this paper, we investigate the continuity of linear and sublinear correspondences defined on cones in normed spaces. We also generalize some known results for sublinear correspondences.
Linear correspondence
sublinear correspondence
cone
2015
02
01
43
55
http://bims.iranjournals.ir/article_593_c6ba89a04e2a91caadf240efa0328257.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
Some properties of a class of polyhedral semigroups based upon the subword reversing method
M.
Minisker
In this paper a certain class of polyhedral semigroups which has a presentation $$ is examined. The completeness of the presentation and solvability of word problem of this class of semigroups is determined. Moreover the combinatorial distance between two words is determined.
Polyhedral semigroup
complete
presentation
subword reversing
2015
02
01
57
63
http://bims.iranjournals.ir/article_589_e3fbd66b4893953e73be77cbbe9ce05c.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
Detection of a nontrivial element in the stable homotopy groups of spheres
H.
Yu
Y.
Kou
H.
Zhao
Let $p$ be a prime with $pgeq 7$ and $q=2(p-1)$. In this paper we prove the existence of a nontrivial product of filtration $s+4$ in the stable homotopy groups of spheres. This nontrivial product is shown to be represented up to a nonzero scalar by the product element $widetilde{gamma}_{s}b_{n-1}g_{0}in {Ext}_{mathcal{A}}^{s+4,(p^n+sp^2+sp+s)q+s-3}(mathbb{Z}/p,mathbb{Z}/p)$ in the Adams spectral sequence where $ngeq 2$ and $3leq sleq p-1$.
Stable homotopy groups of sphere
Adams spectral sequence
May spectral sequence
2015
02
01
65
85
http://bims.iranjournals.ir/article_590_85ba0e058a40f200e803319d8a76cec7.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
The inﬂuence of S-embedded subgroups on the structure of ﬁnite groups
J
Li
W.
Shi
D.
Yu
Let H be a subgroup of a group G. H is said to be S-embedded in G if G has a normal T such that HT is an S-permutable subgroup of G and H ∩ T ≤ H sG, where H denotes the subgroup generated by all those subgroups of H which are S-permutable in G. In this paper, we investigate the inﬂuence of minimal S-embedded subgroups on the structure of ﬁnite groups.
We determine the structure the ﬁnite groups with some minimal S-embedded subgroups. We also give some new characterizations of p-nilpotency of ﬁnite groups in terms of S-embedding property. As applications, some previous known results are generalized.
finite groups
S-embedded subgroups
the generalized Fitting subgroups
soluble
groups
p-nilpotent groups
2015
02
01
87
100
http://bims.iranjournals.ir/article_603_1e5a0147e3dd5c95ac6a68807f37a3d4.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
On the eigenvalues of normal edge-transitive Cayley graphs
M.
Ghorbani
A graph $Gamma$ is said to be vertex-transitive or edge- transitive if the automorphism group of $Gamma$ acts transitively on $V(Gamma)$ or $E(Gamma)$, respectively. Let $Gamma=Cay(G,S)$ be a Cayley graph on $G$ relative to $S$. Then, $Gamma$ is said to be normal edge-transitive, if $N_{Aut(Gamma)}(G)$ acts transitively on edges. In this paper, the eigenvalues of normal edge-transitive Cayley graphs of the groups $D_{2n}$ and $T_{4n}$ are given.
Eigenvalues
Cayley graphs
normal graph
2015
02
01
101
107
http://bims.iranjournals.ir/article_592_ae5f0b2ad69282e3e8f70f5873d4a9cd.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
Strictly Kähler-Berwald manifolds with constant holomorphic sectional curvature
X.
Chen
R.
Yan
In this paper, the authors prove that a strictly Kähler-Berwald manifold with nonzero constant holomorphic sectional curvature must be a Kähler manifold.
complex Finsler manifold
holomorphic sectional curvature
Kaehler-Berwald
manifold
2015
02
01
109
120
http://bims.iranjournals.ir/article_591_b9a0e0046a139b2001f811bdf8f8a8a6.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
Supercyclic tuples of the adjoint weighted composition operators on Hilbert spaces
Y. X.
Liang
Z. H.
Zhou
We give some sufficient conditions under which the tuple of the adjoint of weighted composition operators $(C_{omega_1,varphi_1}^* , C_{omega_2,varphi_2}^*)$ on the Hilbert space $mathcal{H}$ of analytic functions is supercyclic.
Supercyclic
adjoint
weighted composition operators
Hilbert space
2015
02
01
121
139
http://bims.iranjournals.ir/article_600_6d1c998b395dc1565dd2c846c6c74e92.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
Optimal asset control of the diffusion model under consideration of the time value of ruin
H.
Dai
C.
Tang
In this paper, we consider the optimal asset control of a financial company which can control its liquid reserves by paying dividends and by issuing new equity. We assume that the liquid surplus of the company in the absence of control is modeled by the diffusion model. It is a hot topic to maximize the expected present value of dividends payout minus equity issuance until the time of bankruptcy. We study this problem under consideration of the time value of ruin. By constructing two categories of suboptimal models, one with classical model without equity issuance, and the other which never goes bankrupt by equity issuance, the optimal problem is addressed. At the end, some numerical examples and interesting economic interpretations are presented.
Optimal dividend control
optimal financing
control
time value of ruin
2015
02
01
141
158
http://bims.iranjournals.ir/article_594_47a7d6a93e62f77f04be6701ab83e08a.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
The category of monoid actions in Cpo
M.
Mahmoudi
H.
Moghbeli-Damaneh
In this paper, some categorical properties of the category ${bf Cpo}_{{bf Act}text{-}S}$ of all {cpo $S$-acts}, cpo's equipped with actions of a monoid $S$ on them, and strict continuous action-preserving maps between them is considered. In particular, we describe products and coproducts in this category, and consider monomorphisms and epimorphisms. Also, we show that the forgetful functor from ${bf Cpo}_{{bf Act}text{-}S}$ to the category of cpo's has both a left and a right adjoint.
Directed complete partially ordered set
product
co-product
cartesian closed
2015
02
01
159
175
http://bims.iranjournals.ir/article_595_990da986cde9498bd05410f7b514ebda.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
Almost multiplicative linear functionals and approximate spectrum
E.
Anjidani
We define a new type of spectrum, called δ-approximate spectrum, of an element a in a complex unital Banach algebra A and show that the δ-approximate spectrum σ_δ (a) of a is compact. The relation between the δ-approximate spectrum and the usual spectrum is investigated. Also an analogue of the classical Gleason-Kahane-Zelazko theorem is established: For each ε>0, there is δ>0 such that if ϕ is a linear functional with ϕ(a)∈σ_δ (a) for all a∈A, then ϕ is ε-almost multiplicative. Finally, we use these ideas to provide a sufficient condition for a δ-almost multiplicative functional to be multiplicative.
almost multiplicative linear functional
Ransford spectrum
pseudospectrum
condition spectrum
Gleason-Kahane-Zelazko theorem
2015
02
01
177
187
http://bims.iranjournals.ir/article_596_bec59d33577ac7d73d2c66407e9eec46.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
On the oriented perfect path double cover conjecture
B.
Bagheri Gh.
B.
Omoomi
An oriented perfect path double cover (OPPDC) of a graph $G$ is a collection of directed paths in the symmetric orientation $G_s$ of $G$ such that each arc of $G_s$ lies in exactly one of the paths and each vertex of $G$ appears just once as a beginning and just once as an end of a path. Maxov{'a} and Ne{v{s}}et{v{r}}il (Discrete Math. 276 (2004) 287-294) conjectured that every graph except two complete graphs $K_3$ and $K_5$ has an OPPDC and they claimed that the minimum degree of the minimal counterexample to this conjecture is at least four. In the proof of their claim, when a graph is smaller than the minimal counterexample, they missed to consider the special cases $K_3$ and $K_5$. In this paper, among some other results, we present the complete proof for this fact. Moreover, we prove that the minimal counterexample to this conjecture is $2$-connected and $3$-edge-connected.
Keywords: Oriented perfect
path double cover
Oriented cycle
double cover
2015
02
01
189
200
http://bims.iranjournals.ir/article_597_a931117b555271ee48028056b0d0101b.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
The symmetric two-step P-stable nonlinear predictor-corrector methods for the numerical solution of second order initial value problems
A.
Shokri
In this paper, we propose a modification of the second order method introduced in [Q. Li and X. Y. Wu, A two-step explicit $P$-stable method for solving second order initial value problems, textit{Appl. Math. Comput.} {138} (2003), no. 2-3, 435--442] for the numerical solution of IVPs for second order ODEs. The numerical results obtained by the new method for some problems show its superiority in efficiency, accuracy and stability.
Hybrid methods
P-stable
off-step points
predictor-corrector
2015
02
01
201
215
http://bims.iranjournals.ir/article_601_887ac07814abac5ed77af1832d56e7c7.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
On graded classical prime and graded prime submodules
K.
Al-Zoubi
M.
Jaradat
R.
Abu-Dawwas
Let $G$ be a group with identity $e.$ Let $R$ be a $G$-graded commutative ring and $M$ a graded $R$-module. In this paper, we introduce several results concerning graded classical prime submodules. For example, we give a characterization of graded classical prime submodules. Also, the relations between graded classical prime and graded prime submodules of $M$ are studied.
Graded submodules
graded prime submodule
graded classical prime submodule
2015
02
01
217
225
http://bims.iranjournals.ir/article_598_4dd3ba6468b930d4ee8608ff457e8457.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
Bounded approximate connes-amenability of dual Banach algebras
A.
Mahmoodi
We study the notion of bounded approximate Connes-amenability for dual Banach algebras and characterize this type of algebras in terms of approximate diagonals. We show that bounded approximate Connes-amenability of dual Banach algebras forces them to be unital. For a separable dual Banach algebra, we prove that bounded approximate Connes-amenability implies sequential approximate Connes-amenability.
Bounded approximate Connes-amenability
sequential approximate Connes-amenability
multiplier-bounded approximate identity
2015
02
01
227
238
http://bims.iranjournals.ir/article_599_13d35cba7517469d79fb3466b2a1511d.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
$LG$-topology
A.
R. Aliabad
A.
Sheykhmiri
In this paper, we introduce a new model of point free topology for point-set topology. We study the basic concepts in this structure and will find that it is naturally close to point-set topology.
frame
$LGT$-space
open element
compact element
separation axioms
2015
02
01
239
258
http://bims.iranjournals.ir/article_604_4e088485fa8366a329cfd854b0a5001d.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
Weighted composition operators on measurable differential form spaces
M. R.
Jabbarzadeh
F.
Talebi
In this paper, we consider weighted composition operators betweenmeasurable differential forms and then some classic properties of these operators are characterized.
Riemann surfaces
differential forms
(weighted)
composition operators
adjoint operator
2015
02
01
259
267
http://bims.iranjournals.ir/article_605_532b70f6a67cbcb1e36afb525cf3e202.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
Multiple solutions for a perturbed Navier boundary value problem involving the $p$-biharmonic
L.
Ding
The aim of this article is to establish the existence of at least three solutions for a perturbed $p$-biharmonic equation depending on two real parameters. The approach is based on variational methods.
three solutions
Three critical points theorem
$p$-biharmonic equations
Critical point theory
2015
02
01
269
280
http://bims.iranjournals.ir/article_606_eab15c0fadca6127377284f5fa080088.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2015
41
1
On meromorphic solutions of certain type of difference equations
X.
Qi
Y.
Liu
L.
Yang
We mainly discuss the existence of meromorphic (entire) solutions of certain type of non-linear difference equation of the form: $f(z)^m+P(z)f(z+c)^n=Q(z)$, which is a supplement of previous results in [K. Liu, L. Z. Yang and X. L. Liu, Existence of entire solutions of nonlinear difference equations, Czechoslovak Math. J. 61 (2011), no. 2, 565--576, and X. G. Qi, Value distribution and uniqueness of difference polynomials and entire solutions of difference equations, Ann. Polon. Math.
Difference equation
Meromorphic functions
order
2015
02
01
281
289
http://bims.iranjournals.ir/article_607_13646b482767ce8701ff3d6ab7c2b254.pdf