2018-11-15T23:19:56Z
http://bims.iranjournals.ir/?_action=export&rf=summon&issue=84
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
Bulletin of the Iranian Mathematical Society
2016
08
01
http://bims.iranjournals.ir/article_832_4119b663aedfbafd2eacfcbf800710fb.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
The geometric properties of a degenerate parabolic equation with periodic source term
G.
Guo
J. Q.
Pan
In this paper, we discuss the geometric properties of solution and lower bound estimate of ∆um−1 of the Cauchy problem for a degenerate parabolic equation with periodic source term ut =∆um+ upsint. Our objective is to show that: (1)with continuous variation of time t, the surface ϕ = [u(x,t)]mδq is a complete Riemannian manifold floating in space RN+1and is tangent to the space RN at ∂H0(t); (2)the surface u = u(x,t) is tangent to the hyperplane W(t) at ∂Hu(t).
Degenerate parabolic equation
~Riemannian manifold
~Periodic source term
2016
08
01
799
808
http://bims.iranjournals.ir/article_833_3a19f3cfd152e71e5060b6ee86fda34e.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
Constructing vertex decomposable graphs
E.
Lashani
A.
Soleyman Jahan
Recently, some techniques such as adding whiskers and attaching graphs to vertices of a given graph, have been proposed for constructing a new vertex decomposable graph. In this paper, we present a new method for constructing vertex decomposable graphs. Then we use this construction to generalize the result due to Cook and Nagel.
Finite graph
well-covered graph
independence complex
edge ideal
vertex decomposable graph
2016
08
01
809
817
http://bims.iranjournals.ir/article_834_0e4d232717c9878e672368f90111370c.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
A limited memory adaptive trust-region approach for large-scale unconstrained optimization
M.
Ahookhosh
K.
Amini
M.
Kimiaei
M. R.
Peyghami
This study concerns with a trust-region-based method for solving unconstrained optimization problems. The approach takes the advantages of the compact limited memory BFGS updating formula together with an appropriate adaptive radius strategy. In our approach, the adaptive technique leads us to decrease the number of subproblems solving, while utilizing the structure of limited memory quasi-Newton formulas helps to handle large-scale problems. Theoretical analysis indicates that the new approach preserves the global convergence to a first-order stationary point under classical assumptions. Moreover, the superlinear and the quadratic convergence rates are also established under suitable conditions. Preliminary numerical experiments show the effectiveness of the proposed approach for solving large-scale unconstrained optimization problems.
Unconstrained optimization
trust-region framework
compact quasi-Newton representation
limited memory technique
adaptive strategy
2016
08
01
819
837
http://bims.iranjournals.ir/article_835_05d125fc7788d3d72bb2e454b7c9ae39.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
Totally umbilical radical transversal lightlike hypersurfaces of Kähler-Norden manifolds of constant totally real sectional curvatures
G.
Nakova
In this paper we study curvature properties of semi - symmetric type of totally umbilical radical transversal lightlike hypersurfaces $(M,g)$ and $(M,widetilde g)$ of a K"ahler-Norden manifold $(overline M,overline J,overline g,overline { widetilde g})$ of constant totally real sectional curvatures $overline nu$ and $overline {widetilde nu}$ ($g$ and $widetilde g$ are the induced metrics on $M$ by the Norden metrics $overline g$ and $overline {widetilde g}$, respectively). We obtain a condition for $overline {widetilde nu}$ (resp. $overline nu$) which is equivalent to eachof the following conditions: $(M,g)$ $(resp., (M,widetilde g))$ is locally symmetric, semi-symmetric, Ricci semi-symmetric and almost Einstein. We construct an example of a totally umbilical radical transversal lightlike hypersurface, which is locally symmetric, semi-symmetric, Ricci semi-symmetric and almost Einstein.
Kähler-Norden manifold
totally real sectional curvature
radical transversal lightlike hypersurface
totally umbilical lightlike hypersurface
2016
08
01
839
854
http://bims.iranjournals.ir/article_836_492ff15de80235a366b9a8fbf01ab827.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
A note on inequalities for Tsallis relative operator entropy
L.
Zou
Y.
Jiang
In this short note, we present some inequalities for relative operator entropy which are generalizations of some results obtained by Zou [Operator inequalities associated with Tsallis relative operator entropy, Math. Inequal. Appl. 18 (2015), no. 2, 401--406]. Meanwhile, we also show some new lower and upper bounds for relative operator entropy and Tsallis relative operator entropy.
Relative operator entropy
Tsallis relative operator entropy
operator inequalities
2016
08
01
855
859
http://bims.iranjournals.ir/article_837_df4210a6e2cdcbb39f8414109f5622bf.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
A module theoretic approach to zero-divisor graph with respect to (first) dual
E.
Momtahan
M.
Baziar
S.
Safaeeyan
Let $M$ be an $R$-module and $0 neq fin M^*={rm Hom}(M,R)$. We associate an undirected graph $gf$ to $M$ in which non-zero elements $x$ and $y$ of $M$ are adjacent provided that $xf(y)=0$ or $yf(x)=0$. We observe that over a commutative ring $R$, $gf$ is connected and diam$(gf)leq 3$. Moreover, if $Gamma (M)$ contains a cycle, then $mbox{gr}(gf)leq 4$. Furthermore if $|gf|geq 1$, then $gf$ is finite if and only if $M$ is finite. Also if $gf=emptyset$, then $f$ is monomorphism (the converse is true if $R$ is a domain). If $M$ is either a free module with ${rm rank}(M)geq 2$ or a non-finitely generated projective module there exists $fin M^*$ with ${rm rad}(gf)=1$ and ${rm diam}(gf)leq 2$. We prove that for a domain $R$ the chromatic number and the clique number of $gf$ are equal.
Zero-divisor graph
Clique number
Chromatic number
Module
2016
08
01
861
872
http://bims.iranjournals.ir/article_838_871ce9b57fe08bf9203f8e500d1cd9ef.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
Center--like subsets in rings with derivations or epimorphisms
H. E.
Bell
M. N.
Daif
We introduce center-like subsets Z*(R,f), Z**(R,f) and Z1(R,f), where R is a ring and f is a map from R to R. For f a derivation or a non-identity epimorphism and R a suitably-chosen prime or semiprime ring, we prove that these sets coincide with the center of R.
Prime ring
semiprime ring
derivation
epimorphism
center-like subset
2016
08
01
873
878
http://bims.iranjournals.ir/article_839_3782dc4a21cf87ae977f69355ec9216b.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
The Ramsey numbers of large trees versus wheels
D.
Zhu
L.
Zhang
D.
Li
For two given graphs $G_1$ and $G_2$, the Ramsey number $R(G_1,G_2)$ is the smallest integer n such that for any graph G of order n, either $G$ contains G1 or the complement of G contains $G_2$. Let Tn denote a tree of order n and Wm a wheel of order m+1. To the best of our knowledge, only $R(T_n,W_m)$ with small wheels are known. In this paper, we show that $R(T_n,W_m)=3n-2$ for odd m with $n>756m^{10}$.
Ramsey number
tree
wheel
2016
08
01
879
880
http://bims.iranjournals.ir/article_840_30a26766892a2873e795eb8000b43f23.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
Coefficient estimates for a subclass of analytic and bi-univalent functions
A.
Zireh
E.
Analouei Audegani
In this paper, we introduce and investigate a subclass of analytic and bi-univalent functions in the open unit disk. Upper bounds for the second and third coefficients of functions in this subclass are founded. Our results, which are presented in this paper, generalize and improve those in related works of several earlier authors.
Analytic functions
Bi-Univalent Functions
Coefficient estimates
starlike functions
Koebe one-quarter theorem
2016
08
01
881
889
http://bims.iranjournals.ir/article_841_1f6a850b3488d0952e36fdcc558e5e53.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
Relative (co)homology of $F$-Gorenstein modules
C.
Zhang
Z.
Li
We investigate the relative cohomology and relative homology theories of $F$-Gorenstein modules, consider the relations between classical and $F$-Gorenstein (co)homology theories.
$F$-Gorenstein projective module
$F$-Gorenstein injective module
relative cohomology
relative homology
2016
08
01
891
902
http://bims.iranjournals.ir/article_842_da59dead14e2b930104ab3b6393aba8e.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
On Black-Scholes equation; method of Heir-equations, nonlinear self-adjointness and conservation laws
M. S.
Hashemi
In this paper, Heir-equations method is applied to investigate nonclassical symmetries and new solutions of the Black-Scholes equation. Nonlinear self-adjointness is proved and infinite number of conservation laws are computed by a new conservation laws theorem.
Black-Scholes equation
Heir-equation
nonclassical symmetry
Nonlinear self-adjointness
Conservation law
2016
08
01
903
921
http://bims.iranjournals.ir/article_843_9440a70bdefec0826847378e3637ce93.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
On the order of a module
S.
Hadjirezaei
S.
Karimzadeh
Abstract. Let $(R,P)$ be a Noetherian unique factorization domain (UFD) and M be a finitely generated R-module. Let I(M)be the first nonzero Fitting ideal of M and the order of M, denoted $ord_R(M)$, be the largest integer n such that $I(M) ⊆ P^n$. In this paper, we show that if M is a module of order one, then either M is isomorphic with direct sum of a free module and a cyclic module or M is isomorphic with a special module represented in the text. We also assert some properties of M while $ord_R(M) = 2.$
Fitting ideals
minimal free presentation
order of a module
2016
08
01
923
931
http://bims.iranjournals.ir/article_844_8c5b86ca03124119d8397dde84a956c0.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
Sufficient conditions for univalence and starlikeness
M. N.
Nunokawa
J.
Sokol
N. E.
Cho
It is known that the condition $mathfrak {Re} left{zf'(z)/f(z)right}>0$, $|z|
Analytic functions
convex functions
starlike functions
univalent functions
2016
08
01
933
939
http://bims.iranjournals.ir/article_845_7d14220cd3142ab48ef16685f5904494.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
On two problems concerning the Zariski topology of modules
H.
Ansari-Toroghy
R.
Ovlyaee-Sarmazdeh
Seyed Sajad
Pourmortazavi
Let $R$ be an associative ring and let $M$ be a left $R$-module. Let $Spec_{R}(M)$ be the collection of all prime submodules of $M$ (equipped with classical Zariski topology). There is a conjecture which says that every irreducible closed subset of $Spec_{R}(M)$ has a generic point. In this article we give an affirmative answer to this conjecture and show that if $M$ has a Noetherian spectrum, then $Spec_{R}(M)$ is a spectral space.
Prime spectrum
classical Zariski topology
spectral space
2016
08
01
941
948
http://bims.iranjournals.ir/article_846_1769c60f5d1f171166300f224d7e2683.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
Complexes of $C$-projective modules
E.
Amanzadeh
M. T.
Dibaei
Inspired by a recent work of Buchweitz and Flenner, we show that, for a semidualizing bimodule $C$, $C$--perfect complexes have the ability to detect when a ring is strongly regular. It is shown that there exists a class of modules which admit minimal resolutions of $C$--projective modules.
Semidualizing
$C$--projective
$mathcal P_C$--resolution
$C$--perfect complex
strongly regular
2016
08
01
949
958
http://bims.iranjournals.ir/article_847_8072eb9287f684dfb94b1ec60af8979a.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
Hyperstability of some functional equation on restricted domain: direct and fixed point methods
A.
Bahyrycz
The study of stability problems of functional equations was motivated by a question of S.M. Ulam asked in 1940. The first result giving answer to this question is due to D.H. Hyers. Subsequently, his result was extended and generalized in several ways.We prove some hyperstability results for the equation g(ax+by)+g(cx+dy)=Ag(x)+Bg(y)on restricted domain. Namely, we show, under some weak natural assumptions, that functions satisfying the above equation approximately (in some sense) must be actually solutions to it.
Hyperstability
linear equation
quadratic equation
p-Wright affine function
fixed point theorem
2016
08
01
959
974
http://bims.iranjournals.ir/article_848_f70737eade2a159a95d98ee8c93435c2.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
On statistical type convergence in uniform spaces
B. T.
Bilalov
T. Y.
Nazarova
The concept of ${mathscr{F}}_{st}$-fundamentality is introduced in uniform spaces, generated by some filter ${mathscr{F}}$. Its equivalence to the concept of ${mathscr{F}}$-convergence in uniform spaces is proved. This convergence generalizes many kinds of convergence, including the well-known statistical convergence.
${mathscr{F}}$-convergence
${mathscr{F}}_{st}$- fundamentality
statistical convergence
a uniform space
2016
08
01
975
986
http://bims.iranjournals.ir/article_849_7288695c066460ba0ef6f0e26ae1a84a.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
Polynomial evaluation groupoids and their groups
H. S.
Kim
P. J.
Allen
J.
Neggers
In this paper, we show how certain metabelian groups can be found within polynomial evaluation groupoids. We show that every finite abelian group can be obtained as a polynomial evaluation groupoid.
polynomial evaluation groupoids
group evaluation polynomial
group
2016
08
01
987
997
http://bims.iranjournals.ir/article_850_1eb6e61f83e959712c8e2809e47d56a9.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
Strongly noncosingular modules
Y.
Alagöz
Y.
Durğun
An R-module M is called strongly noncosingular if it has no nonzero Rad-small (cosingular) homomorphic image in the sense of Harada. It is proven that (1) an R-module M is strongly noncosingular if and only if M is coatomic and noncosingular; (2) a right perfect ring R is Artinian hereditary serial if and only if the class of injective modules coincides with the class of (strongly) noncosingular R-modules; (3)absolutely coneat modules are strongly noncosingular if and only if R is a right Max-ring and injective modules are strongly noncosingular; (4) a commutative ring R is semisimple if and only if the class of injective modules coincides with the class of strongly noncosingular R-modules.
coclosed submodules
(non) cosingular modules
coatomic modules
2016
08
01
999
1013
http://bims.iranjournals.ir/article_851_d18ecbcc8e8e4b588b255c42f726eb89.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
On certain semigroups of transformations that preserve double direction equivalence
L.
Deng
Let TX be the full transformation semigroups on the set X. For an equivalence E on X, let TE*(X) = {α ∈ TX : ∀(x, y) ∈ E ⇔ (xα, yα) ∈ E} It is known that TE*(X) is a subsemigroup of TX. In this paper, we discuss the Green's *-relations, certain *-ideal and certain Rees quotient semigroup for TE*(X).
Transformation semigroups
Equivalence
Green's *-relations
*-Ideal
Rees quotient semigroup
2016
08
01
1015
1024
http://bims.iranjournals.ir/article_852_a64e6817281df6609cd01af3d32c5d45.pdf
Bulletin of the Iranian Mathematical Society
BIMS
1017-060X
1017-060X
2016
42
4
From the Editor-in-Chief
2016
08
01
1025
1026
http://bims.iranjournals.ir/article_853_22686d0fab58cdee00a66c458eb8e1cd.pdf