Displaying 21 – 40 of 2227

Showing per page

A decay estimate for a class of hyperbolic pseudo-differential equations

Sandra Lucente, Guido Ziliotti (1999)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

We consider the equation u t i Λ u = 0 , where Λ = λ D x is a first order pseudo-differential operator with real symbol λ ξ . Under a suitable convexity assumption on λ we find the decay properties for u t , x . These can be applied to the linear Maxwell system in anisotropic media and to the nonlinear Cauchy Problem u t i Λ u = f u , u 0 , x = g x . If f u is a smooth function which satisfies f u u p near u = 0 , and g is small in suitably Sobolev norm, we prove global existence theorems provided p is greater than a critical exponent.

A Dynamic Frictionless Contact Problem with Adhesion and Damage

Mohamed Selmani, Lynda Selmani (2007)

Bulletin of the Polish Academy of Sciences. Mathematics

We consider a dynamic frictionless contact problem for a viscoelastic material with damage. The contact is modeled with normal compliance condition. The adhesion of the contact surfaces is considered and is modeled with a surface variable, the bonding field, whose evolution is described by a first order differential equation. We establish a variational formulation for the problem and prove the existence and uniqueness of the solution. The proofs are based on the theory of evolution equations with...

A general decay estimate for a finite memory thermoelastic Bresse system

Cyril Dennis Enyi, Soh Edwin Mukiawa (2022)

Applications of Mathematics

This work considers a Bresse system with viscoelastic damping on the vertical displacement and heat conduction effect on the shear angle displacement. A general stability result with minimal condition on the relaxation function is obtained. The system under investigation, to the best of our knowledge, is new and has not been studied before in the literature. What is more interesting is the fact that our result holds without the imposition of the equal speed of wave propagation condition, and differentiation...

A general transfer function representation for a class of hyperbolic distributed parameter systems

Krzysztof Bartecki (2013)

International Journal of Applied Mathematics and Computer Science

Results of transfer function analysis for a class of distributed parameter systems described by dissipative hyperbolic partial differential equations defined on a one-dimensional spatial domain are presented. For the case of two boundary inputs, the closed-form expressions for the individual elements of the 2×2 transfer function matrix are derived both in the exponential and in the hyperbolic form, based on the decoupled canonical representation of the system. Some important properties of the transfer...

A hyperbolic model of chemotaxis on a network: a numerical study

G. Bretti, R. Natalini, M. Ribot (2014)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

In this paper we deal with a semilinear hyperbolic chemotaxis model in one space dimension evolving on a network, with suitable transmission conditions at nodes. This framework is motivated by tissue-engineering scaffolds used for improving wound healing. We introduce a numerical scheme, which guarantees global mass densities conservation. Moreover our scheme is able to yield a correct approximation of the effects of the source term at equilibrium. Several numerical tests are presented to show the...

A large data regime for nonlinear wave equations

Jinhua Wang, Pin Yu (2016)

Journal of the European Mathematical Society

We also exhibit a set of localized data for which the corresponding solutions are strongly focused, which in geometric terms means that a wave travels along an specific incoming null geodesic in such a way that almost all of the energy is concentrated in a tubular neighborhood of the geodesic and almost no energy radiates out of this neighborhood.

Currently displaying 21 – 40 of 2227