مجله بین المللی محاسبات و مدل سازی ریاضی
سال ششم شماره 2 (Spring 2016)

The matrix functions appear in several applications in engineering and sciences. The computation of these functions almost involved complicated theory. Thus, improving the concept theoretically seems unavoidable to obtain some new relations and algorithms for evaluating these functions. The aim of this paper is proposing some new reciprocal for the function of block anti diagonal matrices. Moreover, some theorems will be proven and applications will be given.

This paper investigates a discrete-time impatient customer queue with Bernoulli-schedule vacation interruption. The vacation times and the service times during regular busy period and during working vacation period are assumed to follow geometric distribution. We obtain the steady-state probabilities at arbitrary and outside observer's observation epochs using recursive technique. Cost analysis is carried out using particle swarm optimization. Computational experiences with a variety of numerical results are discussed.

Asymptotically exact and nonlocal fourth order nonlinear evolution equations are derived for two coupled fourth order nonlinear evolution equations have been derived in deep water for two capillary-gravity wave packets propagating in the same direction in the presence of wind flowing over water.We have used a general method, based on Zakharov integral equation.On the basis of these evolution equations,the stability analysis is made for a uniform capillary gravity wave train in the presence of another wave train having the same group velocity. Instability condition is obtained and graphs are plotted for maximum growth rate of instability and for wave number at marginal stability against wave steepness for some different values of dimensionless wind velocity.

In this paper, we implement numerical solution of differential equations of frac- tional order based on hybrid functions consisting of block-pulse function and rationalized Haar functions. For this purpose, the properties of hybrid of rationalized Haar functions are presented. In addition, the operational matrix of the fractional integration is obtained and is utilized to convert computation of fractional differential equations into some algebraic equa- tions. We evaluate application of present method by solving some numerical examples.

In this paper, rstly we have introduced to entropy of sequences of fuzzy sets and given some theorems about it. Secondly, the waves P and T which appears in electrocardiograms were transferred to fuzzy sets, by using denition of entropy for sequences of fuzzy sets, and some numerical values were obtained for sequences of waves P and T. Thus any person can make a medical predictions for some cardiac problems using to the numerical values.

We present here, a Haar wavelet method for a class of third order partial dierential
equations (PDEs) arising in impulsive motion of a flat plate. We also, present Adomain
decomposition method to find the analytic solution of such equations. Efficiency and
accuracy have been illustrated by solving numerical examples.