A PRELUDE TO THE THEORY OF RANDOM WALKS IN RANDOM ENVIRONMENTS
F.
REZAKHANLOU
author
text
article
2011
eng
A random walk on a lattice is one of the most fundamental models in probability theory.
When the random walk is inhomogenous and its inhomogeniety comes from an ergodic stationary process, the walk is called a
random walk in a random environment (RWRE). The basic questions such as the law of large numbers (LLN), the central limit theorem (CLT),
and the large deviation principle (LDP) are not fully understood for RWRE. Some known results in the case of LLN and LDP are reviewed.
These results are closely related to the homogenization phenomenon
for Hamilton-Jacobi-Bellman equations when both space and time are discretized.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
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2011
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http://bims.iranjournals.ir/article_321_2248c4b14c7fdc0b2336fbd3371b2af0.pdf
COMPOSITE INTERPOLATION METHOD AND THE
CORRESPONDING DIFFERENTIATION MATRIX
H.
MARZBAN
author
H.
TABRIZIDOOZ
author
text
article
2011
eng
Properties of the hybrid of block-pulse functions and Lagrange
polynomials based on the Legendre-Gauss-type points are
investigated and utilized to define the composite interpolation
operator as an extension of the well-known Legendre interpolation
operator. The uniqueness and interpolating properties are
discussed and the corresponding differentiation matrix is also
introduced. The applicability and effectiveness of the method are
illustrated by two numerical experiments.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
1017-060X
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2011
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34
http://bims.iranjournals.ir/article_322_2b6066753cacb933c98a78dbdfe8997a.pdf
A SYSTEM OF GENERALIZED VARIATIONAL
INCLUSIONS INVOLVING G-eta-MONOTONE MAPPINGS
M.
ROOHI
author
M.
ALIMOHAMMADY
author
text
article
2011
eng
We introduce a new concept of general
$G$-$eta$-monotone operator generalizing the general
$(H,eta)$-monotone operator cite{arvar2, arvar1}, general
$H-$ monotone operator cite{xiahuang} in Banach spaces, and also
generalizing $G$-$eta$-monotone operator cite{zhang}, $(A,
eta)$-monotone operator cite{verma2}, $A$-monotone operator
cite{verma0}, $(H, eta)$-monotone operator cite{fanghuang},
$H$-monotone operator cite{fanghuang1, {fanghuangthompson}},
maximal $eta$-monotone operator cite{fanghuang0} and classical
maximal monotone operators cite{zeid} in Hilbert spaces. We provide
some examples and study some properties of general
$G$-$eta$-monotone operators. Moreover, the generalized proximal
mapping associated with this type of monotone operator is defined
and its Lipschitz continuity is established. Finally, using
Lipschitz continuity of generalized proximal mapping under some
conditions a new system of variational inclusions is solved.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
1017-060X
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2011
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47
http://bims.iranjournals.ir/article_323_98793a2abdc7993aabb4da3945e1d63f.pdf
EXACT SOLUTIONS FOR FLOW OF A SISKO FLUID
IN PIPE
N.
MOALLEMI
author
I.
SHAFIEENEJAD
author
A.
NOVINZADEH
author
text
article
2011
eng
By means of He's homotopy perturbation method
(HPM) an approximate solution of velocity eld is derived for the
ow in straight pipes of non-Newtonian
uid obeying the Sisko
model. The nonlinear equations governing the
ow in pipe are for-
mulated and analyzed, using homotopy perturbation method due
to He. Furthermore, the obtained solutions for velocity eld is
graphically sketched and compared with Newtonian
uid to show
the accuracy of this work. Volume
ux, average velocity and pres-
sure gradient are also calculated. Results reveal that the proposed
method is very eective and simple for solving nonlinear equations
like non-Newtonian
uids.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
1017-060X
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no.
2011
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60
http://bims.iranjournals.ir/article_324_05383a13d44736bbb607dc866bd74fb3.pdf
APPROXIMATION OF STOCHASTIC PARABOLIC
DIFFERENTIAL EQUATIONS WITH TWO DIFFERENT
FINITE DIFFERENCE SCHEMES
A.
SOHEILI
author
M.
NIASAR
author
M.
AREZOOMANDAN
author
text
article
2011
eng
We focus on the use of two stable and accurate explicit
finite difference schemes in order to approximate the solution of
stochastic partial differential equations of It¨o type, in particular,
parabolic equations. The main properties of these deterministic
difference methods, i.e., convergence, consistency, and stability, are
separately developed for the stochastic cases.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
1017-060X
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no.
2011
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83
http://bims.iranjournals.ir/article_325_50c2301dc8a08d7ed9e358edb432b737.pdf
PROJECTED DYNAMICAL SYSTEMS AND
OPTIMIZATION PROBLEMS
A.
MALEK
author
S.
EZAZIPOUR
author
N.
HOSSEINIPOUR-MAHANI
author
text
article
2011
eng
We establish a relationship between general constrained
pseudoconvex optimization problems and globally projected dynamical
systems. A corresponding novel neural network model,
which is globally convergent and stable in the sense of Lyapunov,
is proposed. Both theoretical and numerical approaches are considered.
Numerical simulations for three constrained nonlinear optimization
problems are given to show that the numerical behaviors
are in good agreement with the theoretical results.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
1017-060X
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No. 2
no.
2011
85
100
http://bims.iranjournals.ir/article_326_2e2eda1f0dba9e345cd2cb4e8b33ad8b.pdf
LINEAR ESTIMATE OF THE NUMBER OF ZEROS OF
ABELIAN INTEGRALS FOR A KIND OF QUINTIC
HAMILTONIANS
N.
NYAMORADI
author
H.
ZANGENEH
author
text
article
2011
eng
We consider the number of zeros of the integral $I(h) = oint_{Gamma_h} omega$ of real polynomial form $omega$ of degree not greater than $n$ over a family of vanishing cycles on curves $Gamma_h:$ $y^2+3x^2-x^6=h$, where the integral is considered as a function of the parameter $h$. We prove that the number of zeros of $I(h)$, for $0 < h < 2$, is bounded above by $2[frac{n-1}{2}]+1$.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
1017-060X
37
v.
No. 2
no.
2011
101
116
http://bims.iranjournals.ir/article_327_167f1b64e2cf1377a8f6fed876cb6919.pdf
PAIRED ANISOTROPIC DISTRIBUTION FOR IMAGE
SELECTIVE SMOOTHING
A.
MADANKAN
author
text
article
2011
eng
In this paper, we present a novel approach for image selective smoothing by the evolution of two paired nonlinear
partial differential equations. The distribution coefficient in de-noising equation controls the speed of distribution, and is
determined by the edge-strength function. In the previous works, the edge-strength function depends on isotropic
smoothing of the image, which results in failing to preserve corners and junctions, and may also result in failing to resolve
small features that are closely grouped together. The proposed approach obtains the edge-strength function by solving a
nonlinear distribution equation governed by the norm of the image gradient. This edge-strength function is then introduced
into a well-studied anisotropic distribution model to yield a regularized distribution coefficient for image smoothing. An explicit
numerical scheme is employed to efficiently solve these two paired equations. Compared with the existing methods, the
proposed approach has the advantages of more detailed preservation and implementational simplicity. Experimental results
on the synthesis and real images confirm the validity of the proposed approach.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
1017-060X
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2011
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131
http://bims.iranjournals.ir/article_328_5608c91977234ae7dcadecda4d587e07.pdf
AN INTRODUCTION TO HIGHER CLUSTER
CATEGORIES
A.
BUAN
author
text
article
2011
eng
In this survey, we give an overview over some aspects
of the set of tilting objects in an $m-$cluster category, with focus
on those properties which are valid for all $m geq 1$. We focus on the
following three combinatorial aspects: modeling the set of tilting
objects using arcs in certain polygons, the generalized assicahedra
of Fomin and Reading, and colored quiver mutation.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
1017-060X
37
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No. 2
no.
2011
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157
http://bims.iranjournals.ir/article_329_995a3b87119ae4d18ab2fb1a2224a40c.pdf
ALGEBRAS WITH CYCLE-FINITE STRONGLY SIMPLY
CONNECTED GALOIS COVERINGS
J.
DE LA PENA
author
text
article
2011
eng
Let $A$ be a nite dimensional $k-$algebra and $R$ be a
locally bounded category such that $R rightarrow R/G = A$ is a Galois covering
dened by the action of a torsion-free group of automorphisms
of $R$. Following [30], we provide criteria on the convex subcategories
of a strongly simply connected category R in order to be a cycle-
nite category and describe the module category of $A$. We provide
criteria for $A$ to be of polynomial growth
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
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2011
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186
http://bims.iranjournals.ir/article_330_c71915e6b4ef58de1db68fafba6d960c.pdf
CLUSTER ALGEBRAS AND CLUSTER CATEGORIES
B.
KELLER
author
text
article
2011
eng
These are notes from introductory survey lectures given
at the Institute for Studies in Theoretical Physics and Mathematics
(IPM), Teheran, in 2008 and 2010. We present the definition and
the fundamental properties of Fomin-Zelevinsky’s cluster algebras.
Then, we introduce quiver representations and show how they can
be used to construct cluster variables, which are the canonical generators
of cluster algebras. From quiver representations, we proceed
to the cluster category, which yields a complete categorification of
the cluster algebra and its combinatorial underpinnings.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
1017-060X
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2011
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234
http://bims.iranjournals.ir/article_331_d4a48fe4c80e61417522a29c539ecce5.pdf
Rings of Singularities
H.
LENZING
author
text
article
2011
eng
This paper is a slightly revised version of an introduction into singularity theory corresponding to a series of lectures given at the ``Advanced School and Conference on homological and geometrical methods in representation theory'' at the International Centre for Theoretical Physics (ICTP), Miramare - Trieste, Italy, 11-29 January 2010.
We show how to associate to a triple of positive integers $(p_1,p_2,p_3)$ a two-dimensional isolated graded singularity by an elementary procedure that works over any field $k$ (with no assumptions on characteristic, algebraic closedness or cardinality). This assignment starts from the triangle singularity $x_1^{p_1}+x_2^{p_2}+x_3^{p_3}$ and when applied to the Platonic (or Dynkin) triples, it produces the famous list of A-D-E-singularities. As another particular case, the procedure yields Arnold's famous strange duality list consisting of the 14 exceptional unimodular singularities (and an infinite sequence of further singularities not treated here in detail).
As we are going to show, weighted projective lines and various triangulated categories attached to them play a key role in the study of the triangle and associated singularities.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
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2011
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http://bims.iranjournals.ir/article_332_2305be4c2f9611a65dc6ead6821fd829.pdf
RIGID DUALIZING COMPLEXES
A.
NEEMAN
author
text
article
2011
eng
Let $X$ be a sufficiently nice scheme.
We survey some recent progress on dualizing complexes. It turns
out that a complex in $kinj X$ is dualizing if and only if
tensor product with it induces an equivalence of categories
from Murfet's new
category $kmpr X$ to the category
$kinj X$. In these terms, it
becomes interesting to wonder how to glue such equivalences.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
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no.
2011
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http://bims.iranjournals.ir/article_333_341c4f567b539260a85b4d60696ed342.pdf
ON THE USE OF KULSHAMMER TYPE INVARIANTS
IN REPRESENTATION THEORY
A.
ZIMMERMANN
author
text
article
2011
eng
Since 2005 a new powerful invariant of an algebra has
emerged using the earlier work of Horvath, Hethelyi, Kulshammer
and Murray. The authors studied Morita invariance of a sequence
of ideals of the center of a nite dimensional algebra over a eld
of nite characteristic. It was shown that the sequence of ideals is
actually a derived invariant, and most recently a slightly modied
version of it is an invariant under stable equivalences of Morita
type. The invariant was used in various contexts to distinguish
derived and stable equivalence classes of pairs of algebras in very
subtle situations. Generalisations to non symmetric algebras and to
higher Hochschild (co-)homology were given. This article surveys
the results and gives some of the constructions in more details.
Bulletin of the Iranian Mathematical Society
Iranian Mathematical Society (IMS)
1017-060X
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No. 2
no.
2011
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341
http://bims.iranjournals.ir/article_334_ab264858c64fce7ff1142c607288bc5c.pdf