In this letter, we describe the propagation of longitudinal waves in one-dimensional nonlinear elastic thin rods with material nonlinearity and geometric nonlinearity. Mathematical analysis is used to derive analytical dispersion relationship waves; subsequently, numerical Fourier spectrum method solve wave equation directly results are verify correctness derived relation.

Objective(s):Solid dispersion formulation is the most promising strategy to improve oral bioavailability of poorly water soluble drugs. The aim of this study was to compare the effect of polyvinylpyrrolidone K30 (PVP) and poloxamer-188 (PLX) as carrier in solid dispersion formulations of celecoxib (CLX). Materials and Methods: Solid dispersions of CLX:PVP or CLX:PLX were prepared at different r...

A three-dimensional lattice Boltzmann model with thirty two discrete velocity distribution functions for viscoelastic fluid is presented in this work. The model is based upon the generalized lattice Boltzmann equation constructed in moment space. The nonlinear equilibria of the model have a number of coupling constants that are free parameters. The dispersion equation of the model is analyzed u...

We analyze coherent structures in nonlocal dispersive active-dissipative nonlinear systems, using as a prototype the Kuramoto–Sivashinsky (KS) equation with an additional nonlocal term that contains stabilizing/destabilizing and dispersive parts. As for the local generalized Kuramoto–Sivashinsky (gKS) equation (see, e.g., [T. Kawahara and S. Toh, Phys. Fluids, 31 (1988), pp. 2103–2111]), we sho...

In this paper we take up the question of a small dispersion limit for the Camassa–Holm equation. The particular limit we study involves a modification of the Camassa–Holm equation, seen in the recent theoretical developments by Himonas and Misiołek, as well as the first author, where well-posedness is proved in weak Sobolev spaces. This work led naturally to the question of how solutions actual...

The complex Ginzburg-Landau equation is a universal model which has been used extensively to describe various non-equilibrium phenomena. In the context of lasers, it models the dynamics of a pulse by averaging over the effects that take place inside the cavity. Ti:sapphire femtosecond lasers, however, produce pulses that undergo significant changes in different parts of the cavity during each r...

Propagation of optical pulse in nonlinear media with varying dispersion is both fundamental [1] and important applied problem [2–8] because the dispersion-managed (DM) system, which is a system with periodic dispersion variation along an optical fiber, is one of the most prospective candidate for ultrafast high-bit-rate optical communication lines. Lossless propagation of optical pulse in DM fi...

introduction the movement and fate of solutes in the subsurface in affected by a large number of physical, chemical processes requiring a broad array of mathematical and physical sciences to study and describe solute transport. the dispersion is an important parameter in the advection – dispersion equation, which is used in assessing, and solving the problems related to the contamination and th...

[1] A physically based description is provided for the transverse dispersion coefficient in porous media as a function of Péclet number, Pe. We represent the porous medium as lattices of bonds with square cross section whose radius distribution is the same as computed for Berea sandstone and describe flow (Stokes equation) and diffusion (random walk method) at the pore scale ( mm) to compute th...