Dérivabilité de l'erreur par rapport à la triangulation dans les méthodes d'éléments finis
Die absolute Stetigkeit des positiven Spektrums der Schwingungsgleichungen mit oszillierendem Hauptteil.
Die Mehrstellenformeln für den Laplaceoperator.
Die Methode der finiten Elemente zur Lösung von elliptischen Randwertaufgaben.
Die Rellichsche Abschätzung für die Schwingungsgleichung mit oszillierendem Hauptteil.
Différentiabilité des fonctions finement harmoniques.
Diffusion and propagation problems in some ramified domains with a fractal boundary
This paper is devoted to some elliptic boundary value problems in a self-similar ramified domain of with a fractal boundary. Both the Laplace and Helmholtz equations are studied. A generalized Neumann boundary condition is imposed on the fractal boundary. Sobolev spaces on this domain are studied. In particular, extension and trace results are obtained. These results enable the investigation of the variational formulation of the above mentioned boundary value problems. Next, for homogeneous...
Discrete maximum principle for interior penalty discontinuous Galerkin methods
A class of linear elliptic operators has an important qualitative property, the so-called maximum principle. In this paper we investigate how this property can be preserved on the discrete level when an interior penalty discontinuous Galerkin method is applied for the discretization of a 1D elliptic operator. We give mesh conditions for the symmetric and for the incomplete method that establish some connection between the mesh size and the penalty parameter. We then investigate the sharpness of...
Divergence boundary conditions for vector Helmholtz equations with divergence constraints
Divergence boundary conditions for vector Helmholtz equations with divergence constraints
The idea of replacing a divergence constraint by a divergence boundary condition is investigated. The connections between the formulations are considered in detail. It is shown that the most common methods of using divergence boundary conditions do not always work properly. Necessary and sufficient conditions for the equivalence of the formulations are given.
Does Atkinson-Wilcox Expansion Converges for any Convex Domain?
2000 Mathematics Subject Classification: 35C10, 35C20, 35P25, 47A40, 58D30, 81U40.The Atkinson-Wilcox theorem claims that any scattered field in the exterior of a sphere can be expanded into a uniformly and absolutely convergent series in inverse powers of the radial variable and that once the leading coefficient of the expansion is known the full series can be recovered uniquely through a recurrence relation. The leading coefficient of the series is known as the scattering amplitude or the far...