On asymptotic effects of boundary perturbations in exponentially shaped Josephson junctions

A parabolic integro differential operator L, suitable to describe many phenomena in various physical fields, is considered. By means of equivalence between L and the third order equation describing the evolution inside an exponentially shaped Josephson junction (ESJJ), an asymptotic analysis for (ESJJ) is achieved, explicitly evaluating, boundary contributions related to the Dirichlet problem

Diffusion and wave behaviour in linear Voigt model

A boundary value problem related to a third- order parabolic equation with a small parameter is analized. This equation models the one-dimensional evolution of many dissipative media as viscoelastic fluids or solids, viscous gases, superconducting materials, incompressible and electrically conducting fluids. Moreover, the third-order parabolic operator regularizes various non linear second order wave equations. In this paper, the hyperbolic and parabolic behaviour of the solution is estimated by means of slow time and fast time. As consequence, a rigorous asymptotic approximation for the solution is established

Solitoni, equazione di sine-Gordon, e problemi dissipativi per alcune classi di soluzioni solitoniche

Onde solitarie e solitoni. Kinks e bions per l'equazione di sine-Gordon.Problemi di propagazione solitonica per un'equazione perturbata di sine-Gordon