The purposes of this work are to study the $L^{2}$-stability a Navier-Stokes type model for non-stationary flow in porous media proposed by Hsu and Cheng 1989 develop Lagrange-Galerkin scheme with Adams-Bashforth method solve that numerically.The stability estimate is obtained thanks presence nonlinear drag force term which corresponds Forchheimer term. We derive extending idea characteristics ...

The field generated by scattering of light from a quasi-homogeneous source on a quasi-homogeneous, random medium is investigated. It is found that, within the accuracy of the first-order Born approximation, the far field satisfies two reciprocity relations (sometimes called uncertainty relations). One of them implies that the spectral density (or spectral intensity) is proportional to the convo...

The studies on the alcoholic fermentation with immobilized S. cerevisiae cells on alginate using a bioreactor with stirred beds of biocatalysts indicated that the diffusion inside the biocatalyst particles attenuates or avoids the inhibitory effects, preserving the microbial activity. Using a mathematical model adequate for ethanol formation in heterogeneous systems the kinetic parameters V, KI...