2016
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2
2
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Entropy generation due to unsteady hydromagnetic Couette flow and heat transfer with asymmetric convective cooling in a rotating system
2
2
Entropy generation in an unsteady hydromagnetic Couette flow of a viscous incompressible electrically conducting fluid between two infinite horizontal parallel plates in a rotating system have been analyzed. Both the lower and upper plates of the channel are subjected to asymmetric convective heat exchange with the ambient following the Newton's law of cooling. A numerical solution for governing equations is developed. The influences of the pertinent parameters on the fluid velocity components, temperature, entropy generation and Bejan number are discussed graphically.
1

111
128


Sanatan
Das
Department of Mathematics, University of Gour Banga Malda 732 103, West Bengal, India
Department of Mathematics, University of
Iran
tutusanasd@yahoo.co.in


Rabindranath
Jana
Department of Applied Mathematics, Vidyasagar University Midnapore 721 102, West Bengal, India
Department of Applied Mathematics, Vidyasagar
Iran
jana261171@yahoo.co.in


Ali J.
Chamkha
Mechanical Engineering Department, Prince Mohammad Bin Fahd University (PMU), AlKhobar 31952, Kingdom of Saudi Arabia
Mechanical Engineering Department, Prince
Iran
achamkha@pmu.edu.sa
Couette flow
convective cooling
entropy generation and Bejan number
An efficient algorithm for finding the semiobnoxious $(k,l)$core of a tree
2
2
In this paper we study finding the $(k,l)$core problem on a tree which the vertices have positive or negative weights. Let $T=(V,E)$ be a tree. The $(k,l)$core of $T$ is a subtree with at most $k$ leaves and with a diameter of at most $l$ which the sum of the weighted distances from all vertices to this subtree is minimized. We show that, when the sum of the weights of vertices is negative, the $(k,l)$core must be a single vertex. Then we propose an algorithm with time complexity of $O(n^2log n)$ for finding the $(k,l)$core of a tree with pos/neg weight, which is in fact a modification of the one proposed by Becker et al. [Networks 40 (2002) 208].
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129
144


Samane
Motevalli
Faculty of Mathematics, Shahrood University, Shahrood, Iran
Faculty of Mathematics, Shahrood University,
Iran
samane.motevalli@gmail.com


Jafar
Fathali
Faculty of Mathematics, Shahrood University, Shahrood, Iran
Faculty of Mathematics, Shahrood University,
Iran
fathali@shahroodut.ac.ir


Mehdi
Zaferanieh
Department of Mathematics, Hakim Sabzevari University, Sabzevar, Iran
Department of Mathematics, Hakim Sabzevari
Iran
mehdi.zaferanieh@gmail.com
Core
Facility location
Median subtree
Semiobnoxious
Effects of Hall current and ionslip on unsteady hydromagnetic generalised Couette flow in a rotating Darcian channel
2
2
Unsteady hydromagnetic generalised Couette flow of a viscous, incompressible and electrically conducting fluid between two horizontal parallel porous plates Darcian channel in the presence of a uniform transverse magnetic field taking Hall current and ionslip into account in a rotating system is investigated. An exact solution of the governing equations is obtained by Laplace transform technique. The expression for the shear stress at the moving porous plate due to primary and secondary flows is also derived. Asymptotic behavior of the solution is analyzed at the startup and final stage of the motion to gain some physical insight into the flow pattern. Numerical values of primary and secondary velocities and that of shear stress at the moving porous plate of the channel due to primary and secondary flows are displayed graphically for various values of different flow parameters.
1

145
167


Jitendra
Kumar Singh
Department of Mathematics, V. S. K. University, Bellary583105, India
Department of Mathematics, V. S. K. University,
Iran
s.jitendrak@yahoo.com


Shaik
Ghousia Begum
Department of Mathematics, V. S. K. University, Bellary583105, India
Department of Mathematics, V. S. K. University,
Iran
ghousiacc@gmail.com


Naveen
Joshi
Department of Mathematics, V. S. K. University, Bellary583105, India
Department of Mathematics, V. S. K. University,
Iran
joshi.naveen94@gmail.com
Hall current
ionslip
Rotation
Permeability
suction/injection
Simulation of particle diffusion and heat transfer in a twophase turbulent boundary layer using the EulerianEulerian approach
2
2
This work investigates the response of twodimensional, turbulent boundary layer characteristics over a flat plate to the presence of suspended particulate matter. Both phases are assumed to be interacting continua. That is, the carrier fluid equations are considered to be coupled with the particlephase equations. A finitedifference technique with nonuniform grid has been employed for the solution of the governing equations and therefore, interpretation of the results and comparison of the present result with the results of other references. The results clearly demonstrate that the presence of particles damped the fluid turbulence and apparently affects the skin friction and heat transfer characteristics equally.
1

169
187


Pradeep Kumar
Tripathy
Department of Mathematics and Science, U.C.P. Engg. School, Berhampur  760 010, Dist. Ganjam, Odisha, India
Department of Mathematics and Science, U.C.P.
Iran
tripathypk2@gmail.com


Saroj Kumar
Mishra
Khallikote  761030, Dist. Ganjam, Odisha, India
Khallikote  761030, Dist. Ganjam, Odisha,
Iran
s1_mishra@yahoo.com


Ali Jawad
Chamkha
Prince Mohammad Bin Fahd University (PMU), P.O. Box 1664, AlKhobar 31952, Kingdom of Saudi Arabia
Prince Mohammad Bin Fahd University (PMU),
Iran
achamkha@pmu.edu.sa
Particulate suspensions
turbulent boundary layer characteristics
flat plate
finite difference techniques
shear stress
heat transfer
A model for the dynamical study of foodchain system considering interference of top predator in a polluted environment
2
2
The modeling investigation in this paper discusses the system level effects of a toxicant on a three species food chain system. In the models, we have assumed that the presence of top predator reduces the predatory ability of the intermediate predator. The stability analysis of the models is carried out and the sufficient conditions for the existence and extinction of the populations under the stress of toxicant are obtained. Further, it is also found that the predation rate of the intermediate predator is a bifurcating parameter and Hopfbifurcation occurs at some critical value of this parameter. Finally, numerical simulation is carried out to support the analytical results.
1

189
218


Om Prakash
Misra
School of Mathematics and Allied Sciences, Jiwaji University, Gwalior474 011, India
School of Mathematics and Allied Sciences,
Iran
misra_op@rediffmail.com


Raveendra Babu
Annavarapu
School of Mathematics and Allied Sciences, Jiwaji University, Gwalior474 011, India
School of Mathematics and Allied Sciences,
Iran
raveendra96@hotmail.com
stability
Bifurcation
Interference
Lyapunov function
Spline Collocation for system of Fredholm and Volterra integrodifferential equations
2
2
The spline collocation methodÂ is employed to solve a system of linear and nonlinear Fredholm and Volterra integrodifferential equations. The solutions are collocated by cubic Bspline and the integrand is approximated by the NewtonCotes formula. We obtain the unique solution for linear and nonlinear system $(nN+3n)times(nN+3n)$ of integrodifferential equations. This approximation reduces the system of integrodifferential equations to an explicit system of algebraic equations. At the end, some examples are presented to illustrate the ability and simplicity of the method.
1

189
218


Nehzat
Ebrahimi
Department of Mathematics, Islamic Azad University, Central Tehran Branch, Iran
Department of Mathematics, Islamic Azad University
Iran
ebrahimi_nehzat@yahoo.com


Jalil
Rashidinia
Department of Mathematics, Islamic Azad University, Central Tehran Branch, Iran
Department of Mathematics, Islamic Azad University
Iran
rashidinia@iust.ac.ir
System of Fredholm and Volterra integrodifferential equations
Cubic Bspline
NewtonCotes formula
Convergence analysis