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On the G -convergence of Morrey operators

Maria Rosaria Formica, Carlo Sbordone (2003)

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

Following Morrey [14] we associate to any measurable symmetric 2 × 2 matrix valued function A x such that ξ 2 K A x ξ , ξ K ξ 2 a.e. x Ω , ξ R 2 , Ω R 2 ...

On the instantaneous spreading for the Navier–Stokes system in the whole space

Lorenzo Brandolese, Yves Meyer (2002)

ESAIM: Control, Optimisation and Calculus of Variations

We consider the spatial behavior of the velocity field u ( x , t ) of a fluid filling the whole space n ( n 2 ) for arbitrarily small values of the time variable. We improve previous results on the spatial spreading by deducing the necessary conditions u h ( x , t ) u k ( x , t ) d x = c ( t ) δ h , k under more general assumptions on the localization of u . We also give some new examples of solutions which have a stronger spatial localization than in the generic case.

On the Instantaneous Spreading for the Navier–Stokes System in the Whole Space

Lorenzo Brandolese, Yves Meyer (2010)

ESAIM: Control, Optimisation and Calculus of Variations

We consider the spatial behavior of the velocity field u(x, t) of a fluid filling the whole space n ( n 2 ) for arbitrarily small values of the time variable. We improve previous results on the spatial spreading by deducing the necessary conditions u h ( x , t ) u k ( x , t ) d x = c ( t ) δ h , k under more general assumptions on the localization of u. We also give some new examples of solutions which have a stronger spatial localization than in the generic case.

On the long time behavior of KdV type equations

Nikolay Tzvetkov (2003/2004)

Séminaire Bourbaki

In a series of recent papers, Martel and Merle solved the long-standing open problem on the existence of blow up solutions in the energy space for the critical generalized Korteweg- de Vries equation. Martel and Merle introduced new tools to study the nonlinear dynamics close to a solitary wave solution. The aim of the talk is to discuss the main ideas developed by Martel-Merle, together with a presentation of previously known closely related results.

On the long-time behaviour of solutions of the p-Laplacian parabolic system

Paweł Goldstein (2008)

Colloquium Mathematicae

Convergence of global solutions to stationary solutions for a class of degenerate parabolic systems related to the p-Laplacian operator is proved. A similar result is obtained for a variable exponent p. In the case of p constant, the convergence is proved to be ¹ l o c , and in the variable exponent case, L² and W 1 , p ( x ) -weak.

On the nonlinear stabilization of the wave equation

Aissa Guesmia (1998)

Annales Polonici Mathematici

We obtain a precise decay estimate of the energy of the solutions to the initial boundary value problem for the wave equation with nonlinear internal and boundary feedbacks. We show that a judicious choice of the feedbacks leads to fast energy decay.

On the parabolic-elliptic limit of the doubly parabolic Keller-Segel system modelling chemotaxis

Piotr Biler, Lorenzo Brandolese (2009)

Studia Mathematica

We establish new results on convergence, in strong topologies, of solutions of the parabolic-parabolic Keller-Segel system in the plane to the corresponding solutions of the parabolic-elliptic model, as a physical parameter goes to zero. Our main tools are suitable space-time estimates, implying the global existence of slowly decaying (in general, nonintegrable) solutions for these models, under a natural smallness assumption.

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