regularity of velocity averages
Lagrangian approach to deriving energy-preserving numerical schemes for the Euler–Lagrange partial differential equations
We propose a Lagrangian approach to deriving energy-preserving finite difference schemes for the Euler–Lagrange partial differential equations. Noether’s theorem states that the symmetry of time translation of Lagrangians yields the energy conservation law. We introduce a unique viewpoint on this theorem: “the symmetry of time translation of Lagrangians derives the Euler–Lagrange equation and the energy conservation law, simultaneously.” The proposed method is a combination of a discrete counter...
Layering methods for nonlinear partial differential equations of first order
This paper is concerned with generalized, discontinuous solutions of initial value problems for nonlinear first order partial differential equations. “Layering” is a method of approximating an arbitrary generalized solution by dividing its domain, say a half-space , into thin layers , , and using a strict solution in the -th layer. On the interface , is required to reduce to a smooth function approximating the values on that plane of . The resulting stratified configuration of strict solutions...
Le problème de Cauchy pour -application
L'équation Non-homogene de Vécua
Limites hydrodynamiques de l'équation de Boltzmann
Limites réversibles et irréversibles de systèmes de particules.
Il s’agit de comparer les différents résultats et théorèmes concernant dans un cadre essentiellement déterministe des systèmes de particules. Cela conduit à étudier la notion de hiérarchies d’équations et à comparer les modèles non linéaires et linéaires. Dans ce dernier cas on met en évidence le rôle de l’aléatoire. Ce texte réfère à une série de travaux en collaboration avec F. Golse, A. Gottlieb, D. Levermore et N. Mauser.
Linear Pfaff systems with the lower characteristic vectors' set of positive Lebesgue measure.
Linear programming interpretations of Mather’s variational principle
We discuss some implications of linear programming for Mather theory [13, 14, 15] and its finite dimensional approximations. We find that the complementary slackness condition of duality theory formally implies that the Mather set lies in an -dimensional graph and as well predicts the relevant nonlinear PDE for the “weak KAM” theory of Fathi [6, 7, 8, 5].
Linear programming interpretations of Mather's variational principle
We discuss some implications of linear programming for Mather theory [13-15] and its finite dimensional approximations. We find that the complementary slackness condition of duality theory formally implies that the Mather set lies in an n-dimensional graph and as well predicts the relevant nonlinear PDE for the “weak KAM” theory of Fathi [5-8].
Local a priori estimates in Lp for first order linear operators with nonsmooth coefficients.
Local controllability of a 1-D tank containing a fluid modeled by the shallow water equations
We consider a 1-D tank containing an inviscid incompressible irrotational fluid. The tank is subject to the control which consists of horizontal moves. We assume that the motion of the fluid is well-described by the Saint–Venant equations (also called the shallow water equations). We prove the local controllability of this nonlinear control system around any steady state. As a corollary we get that one can move from any steady state to any other steady state.
Local controllability of a 1-D tank containing a fluid modeled by the shallow water equations
We consider a 1-D tank containing an inviscid incompressible irrotational fluid. The tank is subject to the control which consists of horizontal moves. We assume that the motion of the fluid is well-described by the Saint–Venant equations (also called the shallow water equations). We prove the local controllability of this nonlinear control system around any steady state. As a corollary we get that one can move from any steady state to any other steady state.
Lokale Auflösbarkeit von Differentialoperatoren erster Ordnung in einem kritischen Punkt.