2013
37
3.1
3
0
Combined effect of suspended particles and rotation on thermosolutal convection in a viscoelastic fluid saturating a DarcyBrinkman porous medium
2
2
In this paper, the combined effect of suspended (fine dust) particles and rotation on the onset of thermosolutal convection in an elasticoviscous fluid in a porous medium is studied. For the porous medium, the Brinkman model is employed and RivlinEricksen model is used to characterize viscoelastic fluid. By applying normal mode analysis method, the dispersion relation has been derived and solved analytically. It is observed that the rotation, stable solute gradient, suspended particles, gravity field and viscoelasticity introduce oscillatory modes. For stationary convection, it is observed that the rotation, stable solute gradient have a stabilizing effect and suspended particles have a destabilizing effect on the system whereas Darcy number and medium permeability have stabilizing/destabilizing effects under certain conditions. The effects of rotation, stable solute gradient, suspended particles, Darcy number and medium permeability have also been shown graphically.
1

319
325


G. C.
Rana
Department of Mathematics, NSCBM Govt. P. G. College, Hamirpur177 005, Himachal Pradesh
Department of Mathematics, NSCBM Govt. P.
India


R. C.
Thakur
Department of Mathematics, Govt. P. G. College, Dhaliara, Kangra177 103, Himachal Pradesh, India
Department of Mathematics, Govt. P. G. College,
India
Brinkman porous medium
RivlinEricksen fluid
rotation
suspended particles
thermosolutal convection
viscosity
viscoelasticity
Approximation of stochastic advectiondiffusion equation
using compact finite difference technique
2
2
In this paper, we propose a new method for solving the stochastic advectiondiffusion equation of Ito type. In this work, we use a compact finite difference approximation for discretizing spatial derivatives of the mentioned equation and semiimplicit Milstein scheme for the resulting linear stochastic system of differential equation. The main purpose of this paper is the stability investigation of the applied method. Finally, some numerical examples are provided to show the accuracy and efficiency of the proposed technique.
1

327
333


M.
Bishehniasar
Department of Mathematics, University of Sistan and Baluchestan Zahedan, Iran
Department of Mathematics, University of
Iran


A. R.
Soheili
The Center of Excellence on Modeling and Control Systems,
Department of applied Mathematics, School of Mathematical science,
Ferdowsi University of Mashhad, Mashhad
The Center of Excellence on Modeling and
Iran
Stochastic partial differential equation
compact finite difference scheme
Stability
semiimplicit Milstein method
Bayesian and nonbayesian estimation of stress–strength
model for Pareto type I distribution
2
2
This article examines statistical inference for where and are independent but not identically distributed Pareto of the first kind (Pareto (I)) random variables with same scale parameter but different shape parameters. The Maximum likelihood, uniformly minimum variance unbiased and Bayes estimators with Gamma prior are used for this purpose. Simulation studies which compare the estimators are presented. Moreover, sensitivity of Bayes estimator to the prior parameters is considered.
1

335
342


A. I.
Shawky
Department of Statistics, Faculty of Sciences, King Abdulaziz University,
P.O. Box 80203, Jeddah 21589
Department of Statistics, Faculty of Sciences,
Saudi Arabia


F. H.
AlGashgari
Department of Statistics, Faculty of Sciences for Girls, King Abdulaziz University,
P.O. Box 53873, Jeddah 21593, Saudi Arabia
Department of Statistics, Faculty of Sciences
Saudi Arabia
Bayesian estimator
Maximum likelihood estimator (MLE)
Pareto of first kind
uniformly minimum variance unbiased estimator (UMVUE)
stressstrength model
On BCgeneralized Landsberg Finsler metrics
2
2
Equality of curvatures of the Berwald and Cartan connections leads to a new class of Finsler metrics, socalled BCgeneralized Landsberg metrics. Here, we prove that every BCgeneralized Landsberg metric of scalar flag curvature with dimension greater than two is of constant flag curvature.
1

343
347


M.
Zamanzadeh
Bijar Branch, Islamic Azad University Bijar
Bijar Branch, Islamic Azad University Bijar
Iran


B.
Najafi
Department of Mathematics, Faculty of Science, Shahed University of Tehran, Tehran, Iran
Department of Mathematics, Faculty of Science,
Iran
Finsler structure
Landsberg metric
generalized Landsberg metric
scalar flag curvature
A preemptive restarting approach to beating the
inherent instability of Lanczostype algorithms
2
2
Lanczostype algorithms are well known for their inherent instability. They typically breakdown occurs when relevant orthogonal polynomials do not exist. Current approaches to curing breakdown rely on jumping over the nonexistent polynomials to resume computation. This may have to be used many times during the solution process. We suggest an alternative to jumping, which consists of restarting the algorithms that fail. Three different strategies can be taken: (ST1) Restarting following breakdown of the algorithm in use; (ST2) preemptive restarting after a fixed number of iterations; (ST3) restarting when near breakdown is detected through monitoring. We describe a restarting framework with a generic algorithm that invokes one or the other of the three strategies suggested. Four of the most prominent recently developed Lanczostype algorithms namely, and will be presented and then deployed in the restarting framework. However, we will only report on results obtained with strategy ST2 as it is the only viable one at the moment.
1

349
358


M.
Farooq
Department of Mathematics, University of Peshawar, 25120, Khyber Pakhtunkhwa
Department of Mathematics, University of
Pakistan


A.
Salhi
Department of Mathematical Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
Department of Mathematical Sciences, University
United Kingdom
Lanczos algorithm
Systems of Linear Equations
Formal Orthogonal Polynomials, Restarting, Switching, Breakdown
Symplectic Hodge theory, harmonicity, and Thom duality
2
2
We study the notion of harmonicity in the sense of symplectic geometry, and investigate the geometric properties of harmonic Thom forms and distributional Thom currents, dual to different types of submanifolds. We show that the harmonic Thom form associated to a symplectic submanifold is nowhere vanishing. We also construct symplectic smoothing operators which preserve the harmonicity of distributional currents and using these operators, construct harmonic Thom forms for coisotropic submanifolds, which unlike the harmonic forms associated with symplectic submanifolds, are supported in an arbitrary tubular neighborhood of the manifold.
1

359
363


M.
Bahramgiri
Graduate School of Management and Economics Sharif University of Technology
Graduate School of Management and Economics
Iran
Harmonicity
duality
Thom class
Hodge theory
symplectic
distributional currents
smoothing operators
oriented submanifold
Some kinds of fuzzy ideals of ternary semigroups
2
2
Generalizing the concepts of fuzzy (left, right, lateral) ideals, fuzzy quasiideals and fuzzy bi (generalized bi) ideals in ternary semigroups, the notions of fuzzy (left, right, lateral) ideals, fuzzy quasiideals and fuzzy bi (generalized bi) in ternary semigroups are introduced and several related properties are investigated. Some new results are obtained.
1

365
378


N.
Rehman
Department of Basic Sciences, Riphah International University, Islamabad, Pakistan
Department of Basic Sciences, Riphah International
Pakistan


M.
Shabir
2Department of Mathematics, QuaidiAzam University, Islamabad, Pakistan
2Department of Mathematics, QuaidiAzam
Pakistan
Ternary semigroups
fuzzy ideals
fuzzy quasiideals
fuzzy ideals biideals
An optimal control approach for arbitrary order
singularly perturbed boundary value problems
2
2
The aim of this paper is to introduce a new approach for obtaining the numerical solution of singulary perturbed boundary value problems based on an optimal control technique. In the proposed method, first the mentioned equations are converted to an optimal control problem. Then, control and state variables are approximated by Chebychev series. Therefore, the optimal control problem is reduced to a parametric optimal control problem (POC) subject to algebric constraints. Finally, the obtained POC is solved numerically using an iterative optimization technique. In this method, a new idea is proposed which enables us to apply the new technique for almost all kinds of singularly perturbed boundary value problems. Some numerical examples are solved to highlight the advantages of the proposed technique.
1

379
388


M.
Zarepour
Department of Mathematics, Yazd University, P.O. Box: 89195741 Yazd, Iran
Department of Mathematics, Yazd University,
Iran


G. B.
Loghmani
Department of Mathematics, Yazd University
Department of Mathematics, Yazd University
Iran
Singularly perturbed boundary value problem
parametric optimal control
Optimal control problem
Boundary layer problem for system of first order of ordinary differential equations with linear nonlocal boundary conditions
2
2
In this paper we study the boundary layer problems in which boundary conditions are nonlocal. Here we try to find the necessary conditions by the help of fundamental solution to the given adjoint equation. By getting help from these conditions, at first the boundary condition is changed from nonlocal to local. The main aim of this paper is to identify the location of the boundary layer. In other words, at which point the boundary layer is formed.
1

389
396


M.
Jahanshahi
Department of Mathematics, Azarbaijan Shahid Madani University, 5375171379, Tabriz
Department of Mathematics, Azarbaijan Shahid
Iran


A. R.
Sarakhsi
Department of Mathematics, Azarbaijan Shahid Madani University, 5375171379, Tabriz, Iran
Department of Mathematics, Azarbaijan Shahid
Iran


S.
Asharafi
Department of Mathematics, Azarbaijan Shahid Madani University, 5375171379, Tabriz, Iran
Department of Mathematics, Azarbaijan Shahid
Iran


N.
Aliev
Department of Mathematics, Baku State University, Baku, Azerbaijan
Department of Mathematics, Baku State University,
Iran
Singular perturbation problems
boundary layer
fundamental solution
necessary conditions
On generalized Istatistical convergenceof order
2
2
The goal of this paper is to generalize the recently introduced summability method and introduce double statistical convergence of order by using ideal. We also investigate certain properties of this convergence.
1

397
402


E.
Savas
Department of Mathematics, Istanbul Commerce University, UskudarIstanbul
Department of Mathematics, Istanbul Commerce
Turkey
ideal
filter
I double statistical convergence of order α
I_λ double statistical convergence of order α, closed subspace
On characterization of spacelike dual biharmonic curves
in dual Lorentzian Heisenberg group
2
2
In this paper, we study spacelike dual biharmonic curves. We characterize spacelike dual biharmonic curves in terms of their curvature and torsion in the Lorentzian dual Heisenberg group . We give necessary and sufficient conditions for spacelike dual biharmonic curves in the Lorentzian dual Heisenberg group . Therefore, we prove that all spacelike dual biharmonic curves are spacelike dual helix. Moreover, we give their explicit parametrizations of spacelike dual biharmonic curves. Finally, we illustrate our main results in Figs. 1 and 2.
1

403
410


T.
Korpinar
Department of Mathematics, Mus Alparslan University, 49250, Mus, Turkey
Department of Mathematics, Mus Alparslan
Turkey


E.
Turhan
Department of Mathematics, Firat University, 23119, Elazig, Turkey
Department of Mathematics, Firat University,
Turkey


V.
Asil
3Department of Mathematics, Firat University, 23119, Elazig
3Department of Mathematics, Firat University,
Turkey
Bienergy
biharmonic curve
Helix
Heisenberg group
Graded prime spectrum of a graded module
2
2
Let be a graded ring and be a graded module. We define a topology on graded prime spectrum of the graded module which is analogous to that for , and investigate several properties of the topology.
1

411
420


N. A.
Ozkiırisci
Department of Mathematics, Faculty of Arts and Science, Yildiz
Technical University, 34210, Esenler, Istanbul
Department of Mathematics, Faculty of Arts
Turkey


K. H.
Oral
Department of Mathematics, Faculty of Arts and Science, Yildiz
Technical University, 34210, Esenler, Istanbul, Turkey
Department of Mathematics, Faculty of Arts
Turkey


U.
Tekir
Department of Mathematics, Faculty of Arts and Science, Marmara University, 34722, Goztepe, Istanbul, Turkey
Department of Mathematics, Faculty of Arts
Turkey
Graded module
graded prime spectrum
graded prime submodule
The multistep homotopy analysis method: A powerful
scheme for handling nonlinear oscillators
2
2
This paper presents approximate analytical solutions for nonlinear oscillators using the multistep homotopy analysis method (MSHAM). The proposed scheme is only a simple modification of the homotopy analysis method, in which it is treated as an algorithm in a sequence of small intervals (i.e. time step) for finding accurate approximate solutions to the corresponding problems. Several illustrative examples are given to demonstrate the effectiveness of the present method. Figurative comparisons between the MSHAM and the classical fourthorder RungeKutta method (RK4) reveal that this modified method is very effective and convenient.
1

421
429


M.
Zurigat
Department of Mathematics, Al alBayt University, Mafraq, Jordan
Department of Mathematics, Al alBayt University,
Jordan


S.
AlShara
Department of Mathematics, Al alBayt University, Mafraq, Jordan
Department of Mathematics, Al alBayt University,
Jordan


S.
Momani
Department of Mathematics, University of Jordan, Amman
Department of Mathematics, University of
Jordan


A.
Alawneh
Department of Mathematics, University of Jordan, Amman, Jordan
Department of Mathematics, University of
Jordan
Nonlinear oscillators
homotopy analysis method
numerical solutions
A system of generalized resolvent equations involving
generalized pseudocontractive mapping
2
2
Generalized resolvent equations; variational inclusions; algorithm; convergence; generalized pseudocontractive mapping
1

431
438


R.
Ahmad
Department of Mathematics, Aligarh Muslim University, Aligarh202002, India
Department of Mathematics, Aligarh Muslim
India


M.
Akram
Department of Mathematics, Aligarh Muslim University, Aligarh202002
Department of Mathematics, Aligarh Muslim
India
Generalized resolvent equations
variational inclusions
algorithm
convergence
generalized pseudocontractive mapping