فهرست مطالب

Computational Methods for Differential Equations
Volume:1 Issue: 2, Autumn 2013

  • تاریخ انتشار: 1392/07/09
  • تعداد عناوین: 6
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  • M. Behroozifar, S. A. Yousefi* Pages 78-95

    In this paper, we introduce hybrid of block-pulse functions and Bernstein polynomials and derive operational matrices of integration, dual, differentiation, product and delay of these hybrid functions by a general procedure that can be used for other polynomials or orthogonal functions. Then, we utilize them to solve delay differential equations and time-delay system. The method is based upon expanding various time-varying functions as their truncated hybrid functions. Illustrative examples are included to demonstrate the validity, efficiency and applicability of the method.

    Keywords: Delay differential equation, Bernstein polynomial, Hybrid of block-pulse function, Operational matrix
  • Mohammadreza Ahmadi Darani *, Mitra Nasiri Pages 96-107

    In this paper we introduce a type of fractional-order polynomials based on the classical Chebyshev polynomials of the second kind (FCSs). Also we construct the operational matrix of fractional derivative of order $ gamma $ in the Caputo for FCSs and show that this matrix with the Tau method are utilized to reduce the solution of some fractional-order differential equations.

    * The formula is not displayed correctly!

    Keywords: Chebyshev polynomials, orthogonal system, fractional differential equation, fractional-order Chebyshev functions, Operational matrix
  • Esmail Hesameddini*, Azam Rahimi Pages 108-119

    This paper has been devoted to apply the Reconstruction of Variational Iteration Method (RVIM) to handle the systems of integro-differential equations. RVIM has been induced with Laplace transform from the variational iteration method (VIM) which was developed from the Inokuti method. Actually, RVIM overcome to shortcoming of VIM method to determine the Lagrange multiplier. So that, RVIM method provides rapidly convergent successive approximations to the exact solution. The advantage of the RVIM in comparison with other methods is the simplicity of the computation without any restrictive assumptions. Numerical examples are presented to illustrate the procedure. Comparison with the homotopy perturbation method has also been pointed out.

    Keywords: System of integro-differential equations, Volterra equation, Reconstruction of variational iteration method, Homotopy perturbation method
  • Hossein Noroozi, Alireza Ansari * Pages 120-134

    In this article, we prove the existence of extremal positive solution for the distributed order fractional hybrid differential equation$$int_{0}^{1}b(q)D^{q}[frac{x(t)}{f(t,x(t))}]dq=g(t,x(t)),$$using a fixed point theorem in the Banach algebras. This proof is given in two cases of the continuous and discontinuous function $g$, under the generalized Lipschitz and Caratheodory conditions.

    * The formula is not displayed correctly!

    Keywords: Fractional hybrid differential equations, Distributed order, Extremal solutions, Banach algebra
  • Ali Haji Badali *, Mir Sajjad Hashemi, Maryam Ghahremani Pages 135-145
    We introduce a new solution for Kawahara-KdV equations. The Lie group analysis is used to carry out the integration of this equations. The similarity reductions and exact solutions are obtained based on the optimal system method.
    Keywords: Lie symmetries, Symmetry analysis, Optimal system, Infinitesimal Generators, Kawahara-KdV equation
  • Ahmad Neirameh * Pages 146-157
    Solitary wave solutions to the Broer-Kaup equations and approximate long water wave equations are considered challenging by using the rst integral method.The exact solutions obtained during the present investigation are new. This method can be applied to nonintegrable equations as well as to integrable ones.
    Keywords: First integral method, Broer-Kaup equations, Approximate long water wave equations