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Singular solutions to systems of conservation laws and their algebraic aspects

V. M. Shelkovich* (2010)

Banach Center Publications

We discuss the definitions of singular solutions (in the form of integral identities) to systems of conservation laws such as shocks, δ-, δ’-, and δ ( n ) -shocks (n = 2,3,...). Using these definitions, the Rankine-Hugoniot conditions for δ- and δ’-shocks are derived. The weak asymptotics method for the solution of the Cauchy problems admitting δ- and δ’-shocks is briefly described. The algebraic aspects of such singular solutions are studied. Namely, explicit formulas for flux-functions of singular solutions...

Singularités éliminables pour des équations semi-linéaires

Pierre Baras, Michel Pierre (1984)

Annales de l'institut Fourier

Étant donné L un opérateur différentiel d’ordre m sur un ouvert Ω de R N , K un compact de Ω , γ > 1 et γ ' = γ / ( γ - 1 ) , nous montrons que toute solution de “ L u + u γ = 0 sur Ω K , u 0 ” est solution de “ L u + u γ = 0 sur Ω ” dès que la W m , γ ' -capacité de K est nulle. Cette condition s’avère nécessaire quand L est un opérateur elliptique d’ordre 2. Dans ce cas, nous montrons aussi que ` ` L u + u | u | γ - 1 = μ , u | Ω = 0 ' ' μ est une mesure de Radon bornée sur Ω , a une solution si et seulement si μ ne charge pas les ensembles de W 2 , γ ' -capacité nulle.

Singularities of eddy current problems

Martin Costabel, Monique Dauge, Serge Nicaise (2003)

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

We consider the time-harmonic eddy current problem in its electric formulation where the conductor is a polyhedral domain. By proving the convergence in energy, we justify in what sense this problem is the limit of a family of Maxwell transmission problems: Rather than a low frequency limit, this limit has to be understood in the sense of Bossavit [11]. We describe the singularities of the solutions. They are related to edge and corner singularities of certain problems for the scalar Laplace operator,...

Singularities of eddy current problems

Martin Costabel, Monique Dauge, Serge Nicaise (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

We consider the time-harmonic eddy current problem in its electric formulation where the conductor is a polyhedral domain. By proving the convergence in energy, we justify in what sense this problem is the limit of a family of Maxwell transmission problems: Rather than a low frequency limit, this limit has to be understood in the sense of Bossavit [11]. We describe the singularities of the solutions. They are related to edge and corner singularities of certain problems for the scalar Laplace...

Singularities of Maxwell interface problems

Martin Costabel, Monique Dauge, Serge Nicaise (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

We investigate time harmonic Maxwell equations in heterogeneous media, where the permeability μ and the permittivity ε are piecewise constant. The associated boundary value problem can be interpreted as a transmission problem. In a very natural way the interfaces can have edges and corners. We give a detailed description of the edge and corner singularities of the electromagnetic fields.

Singularities of Maxwell’s system in non-hilbertian Sobolev spaces

Wided Chikouche, Serge Nicaise (2008)

Annali della Scuola Normale Superiore di Pisa - Classe di Scienze

We study the regularity of the solution of the regularized electric Maxwell problem in a polygonal domain with data in L p ( Ω ) 2 . Using a duality method, we prove a decomposition of the solution into a regular part in the non-Hilbertian Sobolev space W 2 , p ( Ω ) 2 and an explicit singular one.

Currently displaying 301 – 320 of 1682