George Psihoyios

A new trigonometrically-fitted sixth algebraic order P-C algorithm for the numerical solution of the radial schrödinger equation

The new scheme developed in this paper is a new trigonometrically-fitted predictor-corrector (P-C) scheme based on the Adams-Bashforth-Moulton P-C methods. In particular, our predictor is based on the fifth algebraic order Adams-Bashforth scheme and our corrector on the sixth algebraic order Adams-Moulton scheme. We compared the efficiency of this new scheme against well known methods and the numerical experimentations showed that our scheme is more efficient, even when compared to methods that have been specially designed for the solution of the radial Schrodinger equation.

Some general formulae for the stability function of explicit advanced step-point (EAS) methods

In this paper, we present certain general formulae for the stability function of explicit advanced step-point (EAS) methods ^[^1^,^2^]. The stability function of EAS methods is quite complicated and appropriate general formulae will facilitate stability analysis and further computational manipulation of these and similar methods. A brief background and a description of the approach followed are also given in the first two sections.

Modelling fuzzy universal resource identifiers: A first approach

A universal resource identifier (or URI) is a compact string of characters for identifying an abstract or physical resource, providing a simple and extensible means for identifying that resource [1] in the world wide web. In this paper, we present a new modelling approach of extending this identifier to encompass paths of a type of directed labelled fuzzy trees.