eng
University of Guilan
Journal of Mathematical Modeling
2345-394X
2382-9869
2015-06-01
3
1
1
13
198
مقاله پژوهشی
SDO relaxation approach to fractional quadratic minimization with one quadratic constraint
Maziar Salahi
salahim@guilan.ac.ir
1
Arezo Zare
ze.arezou@gmail.com
2
Faculty of Mathematical Sciences, University of Guilan,Rasht, Iran
Faculty of Mathematical Sciences, University of Guilan,Rasht, Iran
In this paper, we study the problem of minimizing the ratio of two quadratic functions subject to a quadratic constraint. First we introduce a parametric equivalent of the problem. Then a bisection and a generalized Newton-based method algorithms are presented to solve it. In order to solve the quadratically constrained quadratic minimization problem within both algorithms, a semidefinite optimization relaxation approach is presented. Finally, two set of examples are presented to compare the performance of algorithms.
http://jmm.guilan.ac.ir/article_198_2afefd8e0fbd7908279afb268bcdcf96.pdf
Fractional quadratic optimization
nonconvex problem
convex optimization
semidefinite optimization
eng
University of Guilan
Journal of Mathematical Modeling
2345-394X
2382-9869
2015-06-01
3
1
15
32
196
مقاله پژوهشی
Dynamical behavior and synchronization of hyperchaotic complex T-system
Hossein Kheiri
h-kheiri@tabrizu.ac.ir
1
Bashir Naderi
b_naderi@pnu.ac.ir
2
Faculty of Mathematical Sciences, University of Tabriz, Tabriz, Iran
Department of Mathematics, Payame Noor University, Iran
In this paper, we introduce a new hyperchaotic complex T-system. This system has complex nonlinear behavior which we study its dynamical properties including invariance, equilibria and their stability, Lyapunov exponents, bifurcation, chaotic behavior and chaotic attractors as well as necessary conditions for this system to generate chaos. We discuss the synchronization with certain and uncertain parameters via adaptive control. For synchronization, we use less controllers than the dimension of the proposed system. Also, we prove that the error system is asymptotically stable by using a Lyapunov function. Numerical simulations are computed to check the analytical expressions.
http://jmm.guilan.ac.ir/article_196_8b4648b64fca3b8b5a1909e25a16abaf.pdf
Lyapunov stability
Synchronization
Chaos
Adaptive control
eng
University of Guilan
Journal of Mathematical Modeling
2345-394X
2382-9869
2015-06-01
3
1
33
48
197
مقاله پژوهشی
An efficient numerical method for singularly perturbed second order ordinary differential equation
Jugal Mohapatra
jugal@nitrkl.ac.in
1
Manas kumar Mahalik
513ma1002@nitrkl.ac.in
2
Department of Mathematics, National Institute of Technology Rourkela, India
Department of Mathematics, National Institute of Technology Rourkela, India
In this paper an exponentially fitted finite difference method is presented for solving singularly perturbed two-point boundary value problems with the boundary layer. A fitting factor is introduced and the model equation is discretized by a finite difference scheme on an uniform mesh. Thomas algorithm is used to solve the tri-diagonal system. The stability of the algorithm is investigated. It is shown that the proposed technique is of first order accurate and the error constant is independent of the perturbation parameter. Several problems are solved and numerical results are presented to support the theoretical error bounds established.
http://jmm.guilan.ac.ir/article_197_ce87e8a8bfb327a62b9bc4f0cd2912ba.pdf
Singular perturbation problems
boundary layers
Thomas algorithm
exponential fitting factor
uniform convergence
eng
University of Guilan
Journal of Mathematical Modeling
2345-394X
2382-9869
2015-06-01
3
1
49
75
205
مقاله پژوهشی
Hydromagnetic Couette flow of class-II and heat transfer through a porous medium in a rotating system with Hall effects
Gauri Shanker Seth
gsseth ism@yahoo.com
1
Prashanta Kumar Mandal
ism.prashanta@gmail.com
2
Rohit Sharma
rohit.iitg08@gmail.com
3
Department of Applied Mathematics, Indian School of Mines, Dhanbad-826004, India
Department of Applied Mathematics, Indian School of Mines, Dhanbad-826004, India
Department of Applied Mathematics, Indian School of Mines, Dhanbad-826004, India
Steady hydromagnetic Couette flow of class-II of a viscous, incompressible and electrically conducting fluid through a porous medium in a rotating system taking Hall current into account is investigated. Heat transfer characteristics of the fluid flow are considered taking viscous and Joule dissipations into account. It is noticed that there exists flow separation at the moving plate in the secondary flow direction on increasing either rotation parameter $K^2$ when Hall current parameter $m = 0.5$ or $m$ when $K^2 = 7$. Also there exists flow separation at the moving plate in the secondary flow direction on increasing either magnetic parameter $M^2$ for every value of porosity parameter $K_1$ or $K_1$ when $M^2 = 15$.
http://jmm.guilan.ac.ir/article_205_9dfc74ef6cd9798bedaed2a07880d060.pdf
Couette flow of class-II
Porous medium
Coriolis force
Hall current
viscous and Joule dissipations
eng
University of Guilan
Journal of Mathematical Modeling
2345-394X
2382-9869
2015-06-01
3
1
77
89
201
مقاله پژوهشی
Bernoulli matrix approach for matrix differential models of first-order
Ahmad Golbabai
golbabai@iust.ac.ir
1
Samaneh Panjeh Ali Beik
panjehali@iust.ac.ir
2
School of Mathematics, Iran University of Science and Technology, Tehran, Iran
School of Mathematics, Iran University of Science and Technology, Tehran, Iran
The current paper contributes a novel framework for solving a class of linear matrix differential equations. To do so, the operational matrix of the derivative based on the shifted Bernoulli polynomials together with the collocation method are exploited to reduce the main problem to system of linear matrix equations. An error estimation of presented method is provided. Numerical experiments are reported to demonstrate the applicably and efficiency of the propounded technique.
http://jmm.guilan.ac.ir/article_201_603705fa691297a3e173ef4db4941979.pdf
Linear matrix differential equation
Bernoulli polynomials
operational matrix of derivative
error estimation
eng
University of Guilan
Journal of Mathematical Modeling
2345-394X
2382-9869
2015-06-01
3
1
91
101
199
مقاله پژوهشی
Determining the order of minimal realization of descriptor systems without use of the Weierstrass canonical form
Kamele Nassiri Pirbazari
k-nasiri@guilan.ac.ir
1
Mehdi Azari
mr.mehdiazari@yahoo.com
2
Faculty of Mathematical Sciences, University of Guilan, Rasht, Iran
Faculty of Mathematical Sciences, University of Guilan, Rasht, Iran
A common method to determine the order of minimal realization of a continuous linear time invariant descriptor system is to decompose it into slow and fast subsystems using the Weierstrass canonical form. The Weierstrass decomposition should be avoided because it is generally an ill-conditioned problem that requires many complex calculations especially for high-dimensional systems. The present study finds the order of minimal realization of a continuous linear time invariant descriptor system without use of the Weierstrass canonical form.
http://jmm.guilan.ac.ir/article_199_73509e717ef96f2eab01c1417ed30360.pdf
Descriptor system
minimal realization
Weierstrass canonical form