May 2009

A collocation multistep method for integrating ordinary differential equations on manifolds

  This paper concerns a family of generalized collocation multistep methods that evolves the numerical solution of ordinary differential equations on configuration spaces formulated as homogeneous manifolds. Collocating the general linear method at x = xx+k for k = 0,1,….s, , we obtain the discrete scheme which can be adapted to homogeneous spaces. Varying the values...

Author(s):   J. O. Fatokun and I. K. O. Ajibola

May 2009

When does the pooled variance t-test fail?

  The pooled variance t-tests used prominently for comparing means between two groups is usually restricted with the assumptions of normality and homogeneity of variances. However, the violation of the assumptions happens in many real world data. In this study, the conditions where the pooled variance t-test would fail were investigated. The performance of the t-test was evaluated under different...

Author(s):   Teh Sin Yin and Abdul Rahman Othman

May 2009

Application of variational iteration method to coupled system of nonlinear partial differential physical equations

  In this article 2 examples of the coupled system of nonlinear partial differential physical equations including diffusion-reaction equation have been investigated by means of variational iteration method which is a new numerical method for solving these types of equations. The results are presented finally in comparison with the exact solution, which show a good agreement and consistency with the exact...

Author(s):   Abdoul R. Ghotbi, A. Barari, M. Omidvar and D. D. Ganji

May 2009

A class of collocation methods for general second order ordinary differential equations

  In this paper, self starting hybrid block method of order (4,3,3)T is proposed for the solution of general second order initial value problem of the form Y” = f (x, y, y’) directly without reducing it to first systems of odes. The continuous formation of the integrator enable us to differentiate and evaluate at some grids and off-grid points to take care of...

Author(s):   Y. A. Yahaya and A. M. Badmus 

May 2009

Pre A*-Algebra as a Poset

  This paper is a study on algebraic structure of pre A*- algebra. We define center of a pre A*-algebra, B(A) = {x Î A/ x Ú x0/0 1} and prove that B(A) is a Boolean algebra. We define ordering relation  on pre A*- algebra A by x ≤ y if yÙx = xÙy = x and prove that ≤ is a partial ordering on A and also find necessary conditions...

Author(s):   J. Venkateswara Rao and K. Srinivasa Rao