We construct a simple mathematical model that describes the dynamics of transmission COVID-19 disease in human population. It accounts for various phases and its mode contact through infectious humans surfaces. The contribution asymptomatic is well represented. system ordinary dierential equations evolution range states due to emergence an index case. analysis includes establishment basic repro...

introduction: spect is a diagnostic imaging technique the main disadvantage of which is the existence of poisson noise. so far, different methods have been used by scientists to improve spect images. the wavelet transform is a new method for de-noising which is widely used for noise reduction and quality enhancement of images. the purpose of this paper is evaluation of noise reduction in spect ...

This paper will present an enhancement technique based upon splitting -rooting method in wavelet domain. Wavelets transform concentrate most of the energy in the approximation coefficient. In splitting signal, a twodimensional image is represented uniquely by a set of onedimensional signal, which carries the spectral information of the image at frequency points of specific sets. Using splitting...

in this paper, differential transform method (dtm) is described and is applied to solve systems of nonlinear ordinary differential equations which is arising in hiv infections of cell. intervals of validity of the solution will be extended by using pade approximation. the results also will be compared with those results obtained by runge-kutta method. the technique is described and is illustrat...

in chemical engineering, several processes are represented by singular boundary value problems. in general, classical numerical methods fail to produce good approximations for the singular boundary value problems. in this paper, chebyshev finite difference (chfd) method and dtm-pad´e method, which is a combination of differential transform method (dtm) and pad´e approximant, are applied for sol...

Some estimates are proved for the generalized Fourier-Bessel transform in the space (L^2) (alpha,n)-index certain classes of functions characterized by the generalized continuity modulus.