Amirkabir University of Technology

About: Amirkabir University of Technology is a education organization based out in Tehran, Iran. It is known for research contribution in the topics: Nonlinear system & Finite element method. The organization has 15254 authors who have published 31165 publications receiving 487551 citations. The organization is also known as: Tehran Polytechnic & Tehran Polytechnic University.

The use of He's variational iteration method for solving the telegraph and fractional telegraph equations

Abstract: In this paper the variational iteration method is used to compute the solution for the linear, variable coefficient, fractional derivative and multi space telegraph equations. The method constructs a convergent sequence of functions, to approximate the exact solution with a few number of iterations without discretization. Numerical results and comparison with exact solutions are given for some examples in order to show its applicability and efficiency. Copyright © 2009 John Wiley & Sons, Ltd.

Rational Legendre Approximation for Solving some Physical Problems on Semi-Infinite Intervals

Abstract: A numerical technique for solving some physical problems on a semi-infinite interval is presented. Two nonlinear examples are proposed. In the first example the Volterra's population model growth is formulated as a nonlinear differential equation, and in the second example the Lane–Emden nonlinear differential equation is considered. The approach is based on a rational Legendre tau method. The operational matrices of derivative and product of rational Legendre functions are presented. These matrices together with the tau method are utilized to reduce the solution of these physical problems to the solution of systems of algebraic equations. The method is easy to implement and yields very accurate results.

The multi-depot capacitated location-routing problem with fuzzy travel times

Abstract: This paper addresses the fuzzy version of Capacitated Location Routing Problem (CLRP). The proposed CLRP is defined considering opening costs for depots, limited capacities of vehicles and a set of customers with known demands. There are some potential nodes to locate depots, fuzzy travel times between nodes, and also a time window to meet the demand of each customer. Although there exists several papers, manuscripts and technical reports in the literature concerning Location Routing Problem (LRP) extensions and solution procedures, most of them assume the variables to be crisp. In this paper, we present a multi-depot capacitated LRP (MDCLRP) in which travel time between two nodes is a fuzzy variable. A simulation-embedded Simulated Annealing (SA) procedure is proposed in order to solve the problem. The proposed framework is tested using a standard test problem of MDCLRP and results are analyzed and justified. This numerical example shows that the proposed method is robust and could be used in real world problems.