In this paper, piecewise-analytical and numerical solutions of singular perturbation initial-value problems are obtained by an adaptive multi-step differential transform method (MsDTM). The principle of the method is introduced, and then applied to different types of practical problems arising in science and engineering. Analytical and numerical solutions are obtained using piecewise convergent...

This paper describes a new, powerful technique of fingerprint verification based on a perturbation method. The proposed method consists of four parts. The first part performs local FFT band-pass filtering to enhance the cyclic ridge structure in respective local areas. The second part is optimal block-wise shift for preliminary matching. Then, the third part is application of GAT correlation to...

The renormalization constants present in the lattice evaluation of the topolog-ical susceptibility can be non-perturbatively calculated by using the so-called heating method. We test this method for the O(3) non-linear σ-model in two dimensions. We work in a regime where perturbative calculations are exact and useful to check the values obtained from the heating method. The result of the test i...

The perturbation method is applied to numerical solution of the Lane-Emden Equation (LEE)of arbitrary index n, and the global parameters of polytropes are found as function of polytropic index n.

In this paper, we present a new method to evaluate the moving Frenet frame along intersection curves of two parametric surfaces in tangential situations. To resolve such situation, have combined perturbation with classical that works transversal situation. Unlike existent methods, our even if order contact point is more than one.

The adaptive perturbation method decomposes a Hamiltonian by the diagonal elements and nondiagonal of Fock state. state are solvable but can contain information about coupling constants. We study harmonic oscillator with interacting potential, [Formula: see text], where text] constants, is position operator. In this study, each perturbed term has an exact solution. demonstrate accurate spectrum...