Central Tehran Branch. IAU
Journal of Linear and Topological Algebra (JLTA)
2252-0201
2345-5934
01
02
2012
06
01
Weak amenability of (2N)th dual of a Banach algebra
55
65
EN
Mina
Ettefagh
Department of Mathematics, Tabriz Branch, Islamic Azad University, Tabriz, Iran
minaettefagh@gmail.com
Sima
Houdfar
Department of Mathematics, Tabriz Branch, Islamic Azad University, Tabriz, Iran
In this paper by using some conditions, we show that the weak amenability of
(2n)-th dual of a Banach algebra A for some n ⩾ 1 implies the weak amenability of A.
Banach algebra,Arens porducts,Arens regularity,derivation,weak
amenability
http://jlta.iauctb.ac.ir/article_510112.html
http://jlta.iauctb.ac.ir/article_510112_4481b97ff2be6b5aec88a2d5db69c502.pdf
Central Tehran Branch. IAU
Journal of Linear and Topological Algebra (JLTA)
2252-0201
2345-5934
01
02
2012
06
01
A note on uniquely (nil) clean ring
67
69
EN
Shervin
Sahebi
Department of Mathematics, Islamic Azad University, Central Tehran Branch, PO.
Code 14168-94351, Iran
Mina
Jahandar
Department of Mathematics, Islamic Azad University, Central Tehran Branch, PO.
Code 14168-94351, Iran
m66.jahandar@gmail.com
A ring R is uniquely (nil) clean in case for any a 2 R there exists a uniquely
idempotent e 2 R such that a e is invertible (nilpotent). Let C =
(
A V
W B
)
be the Morita
Context ring. We determine conditions under which the rings A;B are uniquely (nil) clean.
Moreover we show that the center of a uniquely (nil) clean ring is uniquely (nil) clean.
Full element,uniquely clean ring,nil clean ring
http://jlta.iauctb.ac.ir/article_510113.html
http://jlta.iauctb.ac.ir/article_510113_61313dd0e6f0354fd7ec465bb79fa807.pdf
Central Tehran Branch. IAU
Journal of Linear and Topological Algebra (JLTA)
2252-0201
2345-5934
01
02
2012
06
01
A mathematically simple method based on denition for computing eigenvalues, generalized eigenvalues and quadratic eigenvalues of matrices
71
81
EN
M
Nili Ahmadabadi
Department of Mathematics, Islamic Azad University, Najafabad Branch, Iran.
nili@phu.iaun.ac.ir
In this paper, a fundamentally new method, based on the denition, is introduced
for numerical computation of eigenvalues, generalized eigenvalues and quadratic eigenvalues
of matrices. Some examples are provided to show the accuracy and reliability of the proposed
method. It is shown that the proposed method gives other sequences than that of existing
methods but they still are convergent to the desired eigenvalues, generalized eigenvalues and
quadratic eigenvalues of matrices. These examples show an interesting phenomenon in the
procedure: The diagonal matrix that converges to eigenvalues gives them in decreasing order
in the sense of absolute value. Appendices A to C provide Matlab codes that implement the
proposed algorithms. They show that the proposed algorithms are very easy to program.
Eigenvalue,Generalized eigenvalue,Quadratic eigenvalue,Numerical
computation,Iterative method
http://jlta.iauctb.ac.ir/article_510114.html
http://jlta.iauctb.ac.ir/article_510114_08524c96a88f2b589b9b2c9a46824457.pdf
Central Tehran Branch. IAU
Journal of Linear and Topological Algebra (JLTA)
2252-0201
2345-5934
01
02
2012
06
01
Numerical Solution of Heun Equation Via Linear Stochastic Differential Equation
83
95
EN
H. R.
Rezazadeh
Department of Mothematics,Karaj Branch,Islamic Azad Univercity,po.code 31485_313 Karaj,Iran
M
Maghasedi
Department of Mothematics,Karaj Branch,Islamic Azad Univercity,po.code 31485_313 Karaj,Iran
maghasedi@kiau.ac.ir
B
shojaee
Department of Mothematics,Karaj Branch,Islamic Azad Univercity,po.code 31485_313 Karaj,Iran
shoujaei@kiau.ac.ir
In this paper, we intend to solve special kind of ordinary differential equations which is called
Heun equations, by converting to a corresponding stochastic differential equation(S.D.E.). So, we construct
a stochastic linear equation system from this equation which its solution is based on computing fundamental
matrix of this system and then, this S.D.E. is solved by numerically methods. Moreover, its asymptotic
stability and statistical concepts like expectation and variance of solutions are discussed. Finally, the attained
solutions of these S.D.E.s compared with exact solution of corresponding differential equations.
Heun equation,Wiener process,Stochastic differential equation,Linear equations system
http://jlta.iauctb.ac.ir/article_510120.html
http://jlta.iauctb.ac.ir/article_510120_6b263c706914ad1317cfc87ee2468b82.pdf
Central Tehran Branch. IAU
Journal of Linear and Topological Algebra (JLTA)
2252-0201
2345-5934
01
02
2012
06
01
A New Inexact Inverse Subspace Iteration for Generalized Eigenvalue Problems
97
113
EN
M
Amirfakhrian
Department of Mathematics, Islamic Azad University, Central Tehran Branch, PO.
Code 14168-94351, Iran.
majiamir@yahoo.com
F
Mohammad
Department of Mathematics, Islamic Azad University, Central Tehran Branch, PO.
Code 14168-94351, Iran.
f.mohammad456@yahoo.com
In this paper, we represent an inexact inverse subspace iteration method for com-
puting a few eigenpairs of the generalized eigenvalue problem Ax = Bx[Q. Ye and P. Zhang,
Inexact inverse subspace iteration for generalized eigenvalue problems, Linear Algebra and
its Application, 434 (2011) 1697-1715 ]. In particular, the linear convergence property of the
inverse subspace iteration is preserved.
Eigenvalue problem,inexact inverse iteration,subspace iteration,inner-outer
iteration,approximation,Convergence
http://jlta.iauctb.ac.ir/article_510116.html
http://jlta.iauctb.ac.ir/article_510116_a6a495230d02a7daa80f2a110513ba3b.pdf
Central Tehran Branch. IAU
Journal of Linear and Topological Algebra (JLTA)
2252-0201
2345-5934
01
02
2012
06
01
Module-Amenability on Module Extension Banach Algebras
111
114
EN
D
Ebrahimi baghaa
Department of Mathematics, Faculty of Science, Islamic Azad University, Centeral
Tehran Branch, P. O. Box 13185/768, Tehran, Iran.
dav.ebrahimibagha@iauctb.ac.ir
Let A be a Banach algebra and E be a Banach A-bimodule then S = A E,
the l1-direct sum of A and E becomes a module extension Banach algebra when equipped
with the algebras product (a; x):(a′; x′) = (aa′; a:x′ + x:a′). In this paper, we investigate
△-amenability for these Banach algebras and we show that for discrete inverse semigroup S
with the set of idempotents ES, the module extension Banach algebra S = l1(ES) l1(S) is
△-amenable as a l1(ES)-module if and only if l1(ES) is amenable as Banach algebra.
Module-amenability,module extension,Banach algebras
http://jlta.iauctb.ac.ir/article_510118.html
http://jlta.iauctb.ac.ir/article_510118_44c07398e7938ba779119a240cd4cf23.pdf
Central Tehran Branch. IAU
Journal of Linear and Topological Algebra (JLTA)
2252-0201
2345-5934
01
02
2012
06
01
E-Clean Matrices and Unit-Regular Matrices
115
118
EN
Sh.A
Safari Sabet
Department of Mathematics, Islamic Azad University, Central Tehran Branch,Code
14168-94351, Iran;
S
Razaghi
Department of Mathematics, Islamic Azad University, Central Tehran Branch,Code
14168-94351, Iran;
razaghi somaye@yahoo.com
Let a; b; k 2 K and u ; v 2 U(K). We show for any idempotent e 2 K,
(
a 0
b 0
)
is
e-clean i
(
a 0
u(vb + ka) 0
)
is e-clean and if
(
a 0
b 0
)
is 0-clean,
(
ua 0
u(vb + ka) 0
)
is too.
matrix ring,unimodular column,unit-regular,clean,e-clean
http://jlta.iauctb.ac.ir/article_510119.html
http://jlta.iauctb.ac.ir/article_510119_5c774e30071a0b38ec4b186ffdb5d653.pdf
Central Tehran Branch. IAU
Journal of Linear and Topological Algebra (JLTA)
2252-0201
2345-5934
01
02
2012
06
01
Recognition of the group G2(5) by the prime graph
115
120
EN
P
Nosratpour
aDepartment of mathematics, ILam Branch, Islamic Azad university, Ilam, Iran;
p.nosratpour@ilam-iau.ac.ir
M.R
Darafsheh
School of Mathematics, statistics and Computer Science, College of Science, University
of Tehran, Tehran, Iran
Let G be a nite group. The prime graph of G is a graph (G) with vertex set
(G), the set of all prime divisors of jGj, and two distinct vertices p and q are adjacent by an
edge if G has an element of order pq. In this paper we prove that if (G) = (G2(5)), then G
has a normal subgroup N such that (N) f2; 3; 5g and G=N
=
G2(5).
prime graph,Recognition,linear group
http://jlta.iauctb.ac.ir/article_510117.html
http://jlta.iauctb.ac.ir/article_510117_39d0770b34588d7c09328c4a5e5401be.pdf