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Approche visqueuse de solutions discontinues de systèmes hyperboliques semilinéaires

Franck Sueur (2006)

Annales de l’institut Fourier

On s’intéresse à des systèmes symétriques hyperboliques multidimensionnels en présence d’une semilinéarité. Il est bien connu que ces systèmes admettent des solutions discontinues, régulières de part et d’autre d’une hypersurface lisse caractéristique de multiplicité constante. Une telle solution u 0 étant donnée, on montre que u 0 est limite quand ε 0 de solutions ( u ε ) ε ] 0 , 1 ] du système perturbé par une viscosité de taille ε . La preuve utilise un problème mixte parabolique et des développements de couches limites....

B q for parabolic measures

Caroline Sweezy (1998)

Studia Mathematica

If Ω is a Lip(1,1/2) domain, μ a doubling measure on p Ω , / t - L i , i = 0,1, are two parabolic-type operators with coefficients bounded and measurable, 2 ≤ q < ∞, then the associated measures ω 0 , ω 1 have the property that ω 0 B q ( μ ) implies ω 1 is absolutely continuous with respect to ω 0 whenever a certain Carleson-type condition holds on the difference function of the coefficients of L 1 and L 0 . Also ω 0 B q ( μ ) implies ω 1 B q ( μ ) whenever both measures are center-doubling measures. This is B. Dahlberg’s result for elliptic measures extended...

Capacitary estimates of positive solutions of semilinear elliptic equations with absorbtion

Moshe Marcus, Laurent Véron (2004)

Journal of the European Mathematical Society

Let Ω be a bounded domain of class C 2 in N and let K be a compact subset of Ω . Assume that q ( N + 1 ) / ( N 1 ) and denote by U K the maximal solution of Δ u + u q = 0 in Ω which vanishes on Ω K . We obtain sharp upper and lower estimates for U K in terms of the Bessel capacity C 2 / q , q ' and prove that U K is σ -moderate. In addition we describe the precise asymptotic behavior of U K at points σ K , which depends on the “density” of K at σ , measured in terms of the capacity C 2 / q , q ' .

Classical solutions to the scalar conservation law with discontinuous initial data

Jędrzej Jabłoński (2013)

Colloquium Mathematicae

Sufficient and necessary conditions for the existence and uniqueness of classical solutions to the Cauchy problem for the scalar conservation law are found in the class of discontinuous initial data and non-convex flux function. Regularity of rarefaction waves starting from discontinuous initial data and their dependence on the flux function are investigated and illustrated in a few examples.

Discontinuous elliptic problems in N without monotonicity assumptions

Silvia Cingolani, Monica Lazzo (2001)

Commentationes Mathematicae Universitatis Carolinae

We prove existence of a positive, radial solution for a semilinear elliptic problem with a discontinuous nonlinearity. We use an approximating argument which requires no monotonicity assumptions on the nonlinearity.

Discontinuous quasilinear elliptic problems at resonance

Nikolaos Kourogenis, Nikolaos Papageorgiou (1998)

Colloquium Mathematicae

In this paper we study a quasilinear resonant problem with discontinuous right hand side. To develop an existence theory we pass to a multivalued version of the problem, by filling in the gaps at the discontinuity points. We prove the existence of a nontrivial solution using a variational approach based on the critical point theory of nonsmooth locally Lipschitz functionals.

Currently displaying 21 – 40 of 194