International Journal of Mathematical Modelling & ComputationsInternational Journal of Mathematical Modelling & Computations
http://ijm2c.iauctb.ac.ir/
Sat, 20 Apr 2019 03:48:06 +0100FeedCreatorInternational Journal of Mathematical Modelling & Computations
http://ijm2c.iauctb.ac.ir/
Feed provided by International Journal of Mathematical Modelling & Computations. Click to visit.Galerkin method for the numerical solution of the advection-diffusion equation by using ...
http://ijm2c.iauctb.ac.ir/article_663819_1132711.html
In this paper, the exponential B-spline functions are used for the numerical solution of the advection-diffusion equation. Two numerical examples related to pure advection in a finitely long channel and the distribution of an initial Gaussian pulse are employed to illustrate the accuracy and the efficiency of the method. Obtained results are compared with some early studies.Mon, 30 Apr 2018 19:30:00 +0100Reproducing Kernel Space Hilbert Method for Solving Generalized Burgers Equation
http://ijm2c.iauctb.ac.ir/article_663825_0.html
In this paper, we present a new method for solving Reproducing Kernel Space (RKS) theory, and iterative algorithm for solving Generalized Burgers Equation (GBE) is presented. The analytical solution is shown in a series in a RKS, and the approximate solution u(x; t) is constructed by truncating the series . The convergence of u(x; t) to the analytical solution is also proved.Sun, 10 Mar 2019 20:30:00 +0100Analytical Solution of Steady State Substrate Concentration of an Immobilized Enzyme Kinetics ...
http://ijm2c.iauctb.ac.ir/article_663820_1132711.html
The nonlinear dynamical system modeling the immobilized enzyme kinetics with Michaelis-Menten mechanism for an irreversible reaction without external mass transfer resistance is considered. Laplace transform homotopy perturbation method is used to obtain the approximate solution of the governing nonlinear differential equation, which consists in determining the series solution convergent to the exact solution or enabling to built the approximate solution of the problem. Numerical solutions are obtained and the results are discussed graphically. The method allows to determine the solution in form of the continuous function, which is significant for the analysis of the steady state dimensionless substrate concentration with dimensionless distance on the different support materials.Mon, 30 Apr 2018 19:30:00 +0100An Approximation Method for Fuzzy Fixed-Charge Transportation Problem
http://ijm2c.iauctb.ac.ir/article_663826_0.html
In this paper, we develop the fuzzy fixed charge transportation problem when the costs are the fuzzy numbers. The first step it transform into the classical fuzzy transportation problem. The next, we obtain the best approximation fuzzy on the optimal value of the fuzzy fixed-charge transportation problem. This method obtains a lower and upper bounds both on the fuzzy optimal value of the fuzzy fixed-charge transportation problem which can be easily obtained by using the approximation solution. Finally, the results of this paper have been illustrated by a numerical example.Sun, 10 Mar 2019 20:30:00 +0100Solving fuzzy impulsive fractional differential equations by Homotopy pertourbation method
http://ijm2c.iauctb.ac.ir/article_663821_1132711.html
In this paper, we study semi-analytical methods entitled Homotopy pertourbation method (HPM) to solve fuzzy impulsive fractional differential equations based on the concept of generalized Hukuhara differentiability. At the end first of Homotopy pertourbation method is defined and its properties are considered completely. Then econvergence theorem for the solution are proved and we will show that the approximate solution convergent to the exact solution. Some examples indicate that this method can be easily applied to many linear and nonlinear problems.Mon, 30 Apr 2018 19:30:00 +0100Compare Adomian Decomposition Method and Laplace Decomposition Method for Burger's-Huxley and ...
http://ijm2c.iauctb.ac.ir/article_663827_0.html
In this paper, Adomian decomposition method (ADM) and Laplace decomposition method (LDM) used to obtain series solutions of Burgers-Huxley and Burgers-Fisher Equations. In ADM the algorithm is illustrated by studying an initial value problem and LDM is based on the application of Laplace transform to nonlinear partial differential equations. In ADM only few terms of the expansion are required to obtain the approximate solution which is found to be accurate and effcient and in LDM does not need linearization, weak nonlinearity assumptions, or perturbation theory. These methods are used to solve the examples and the results are presented in the tables.Sun, 10 Mar 2019 20:30:00 +0100STEADY-STATE AND DYNAMIC SIMULATIONS OF GAS ABSORPTION COLUMN USING MATLAB AND SIMULINK
http://ijm2c.iauctb.ac.ir/article_663822_1132711.html
Separation is one of the most important process in all the chemical industries and the gas absorption is the simplest example of separation process which is generally used for the absorption of dilute components from a gaseous mixture. In the present work, a dynamic system of mathematical equation (algebraic and differential) is modeled to predict the behavior of the absorption column using matrix algebra. The dynamic model was programmed using MATLAB/SIMULINK and S – function was used for building user define blocks to find out the liquid and the gas composition using the standard MATLAB ode45 solver. As a case study, fermentation process is taken as an example to separate CO2 from a mixture of alcohol and CO2 in a tray gas absorber using water as absorbent. The steady state solution was first solved to give the initial condition for the dynamic analysis. Dynamic outcomes for stage compositions was figure out for step changes in the vapor and liquid feed compositions. The model results show good agreement with the practical situation and also compared favorably with results obtained by Bequette. With this work, we are able to provide a readily available simulation that can be used as a test bed for advanced process monitoring.Mon, 30 Apr 2018 19:30:00 +0100A stable iteration to the matrix inversion
http://ijm2c.iauctb.ac.ir/article_663845_0.html
The matrix inversion plays a signifcant role in engineering and sciences. Any nonsingular square matrix has a unique inverse which can readily be evaluated via numerical techniques such as direct methods, decomposition scheme, iterative methods, etc. In this research article, first of all an algorithm which has fourth order rate of convergency with conditional stability will be proposed. Then, for solving stability issue, we introduce a coupled stable scheme that can evaluate the matrix inversion with very acceptable accuracy. Furthermore, the convergence and stability properties of the proposed schemes will be analyzed in details. Numerical experiments are adopted to illustrate the properties of the modified methods.Mon, 11 Mar 2019 20:30:00 +0100Numerical solution of the Lane-Emden equation based on DE transformation via Sinc collocation method
http://ijm2c.iauctb.ac.ir/article_663823_1132711.html
In this paper‎, ‎numerical solution of‎ ‎general Lane-Emden equation via collocation method based on‎ ‎Double Exponential DE transformation is considered‎. ‎The‎ ‎method converts equation to the nonlinear Volterra integral‎ ‎equation‎. ‎Numerical examples show the accuracy of the method.‎ ‎Also‎, ‎some remarks with respect to run-time‎, ‎computational cost‎ ‎and implementation are discussed.Mon, 30 Apr 2018 19:30:00 +0100Analysis of a single server queue with working vacation and vacation interruption
http://ijm2c.iauctb.ac.ir/article_664198_0.html
In this paper, an M/M/1 queue with working vacation and vacation interruption is investigated. The server is supposed to take a working vacation whenever the system becomes empty and if there are at least N customers waiting in the system at a service completion instant, vacation interruption happens and the server resumes a normal working period. A matrix geometric approach is employed to obtain the stationary distribution for mean queue length. Moreover, we have derived the distributions for the mean queue length and the mean waiting time and obtained their stochastic decomposition structures if N=2. Finally, numerical examples are presented.Sat, 06 Apr 2019 19:30:00 +0100A bi-level formulation and a recurrent neural network for centralized resource allocation DEA models
http://ijm2c.iauctb.ac.ir/article_663824_1132711.html
In this paper, the common centralized DEA models are extended to the bi-level centralized resource allocation (CRA) models based on revenue efficiency. Based on the Karush–Kuhn–Tucker (KKT) conditions, the bi-level CRA model is reduced to a one-level mathematical program subject to complementarity constraints (MPCC). A recurrent neural network is developed for solving this one-level mathematical programming problem. Under a proper assumption and utilizing a suitable Lyapunov function, it is shown that the proposed neural network is Lyapunov stable and convergent to an exact optimal solution of the original problem. Finally, an illustrative example is elaborated to substantiate the applicability and effectiveness of the proposed approach.Mon, 30 Apr 2018 19:30:00 +0100