Perturbations singulières et noyaux de Poisson pour les opérateurs frontières homogènes
Perturbations singulières pour une équation hyperbolique dégénérée
Perturbations singulières relatives au problème de Dirichlet dans un demi-espace
Phase field model for mode III crack growth in two dimensional elasticity
A phase field model for anti-plane shear crack growth in two dimensional isotropic elastic material is proposed. We introduce a phase field to represent the shape of the crack with a regularization parameter and we approximate the Francfort–Marigo type energy using the idea of Ambrosio and Tortorelli. The phase field model is derived as a gradient flow of this regularized energy. We show several numerical examples of the crack growth computed with an adaptive mesh finite element method.
Phénomène de couche limite dans un modèle de ferromagnétisme
Populational adaptive evolution, chemotherapeutic resistance and multiple anti-cancer therapies
Resistance to chemotherapies, particularly to anticancer treatments, is an increasing medical concern. Among the many mechanisms at work in cancers, one of the most important is the selection of tumor cells expressing resistance genes or phenotypes. Motivated by the theory of mutation-selection in adaptive evolution, we propose a model based on a continuous variable that represents the expression level of a resistance gene (or genes, yielding a phenotype) influencing in healthy and tumor cells birth/death...
Problème de Cauchy pour opérateurs locaux et «changement de temps»
Nous donnons, dans un cadre très général, des critères de résolubilité pour un certain type de problèmes de Cauchy, et des résultats (entre autres, de compacité) concernant les opérateurs associés à leur résolution. Puis nous considérons les perturbations singulières du type “changement de temps”, et obtenons des conditions suffisantes, et des critères nécessaires et suffisants (modulo prolongement, au besoin) de résolubilité pour le problème de Cauchy perturbé (perturbation d’un problème résoluble)....
Problèmes d’évolution liés à l’énergie de Ginzburg-Landau
Prolongements maximaux positifs d'opérateurs positifs et problèmes de perturbations singulières
Pulsating traveling waves in the singular limit of a reaction-diffusion system in solid combustion
Quasineutral limit of the Euler-Poisson system for ions in a domain with boundaries II
In this paper, we study the quasineutral limit of the isothermal Euler-Poisson equation for ions, in a domain with boundary. This is a follow-up to our previous work [5], devoted to no-penetration as well as subsonic outflow boundary conditions. We focus here on the case of supersonic outflow velocities. The structure of the boundary layers and the stabilization mechanism are different.
Quasi-periodic solutions of nonlinear random Schrödinger equations
Radial minimizer of a -Ginzburg-Landau type functional with normal impurity inclusion.
Radial minimizer of a variant of the -Ginzburg-Landau functional.
Regularity analysis for systems of reaction-diffusion equations
This paper is devoted to the study of the regularity of solutions to some systems of reaction–diffusion equations. In particular, we show the global boundedness and regularity of the solutions in one and two dimensions. In addition, we discuss the Hausdorff dimension of the set of singularities in higher dimensions. Our approach is inspired by De Giorgi’s method for elliptic regularity with rough coefficients. The proof uses the specific structure of the system to be considered and is not a mere...
Relaxation approximations and bounded variation estimates for some partial differential equations.
Resolvent estimates for scalar fields with electromagnetic perturbation.
Robust exponential attractors for singularly perturbed phase-field type equations.
Robust local problem error estimation for a singularly perturbed problem on anisotropic finite element meshes
Singularly perturbed problems often yield solutions with strong directional features, e.g. with boundary layers. Such anisotropic solutions lend themselves to adapted, anisotropic discretizations. The quality of the corresponding numerical solution is a key issue in any computational simulation. To this end we present a new robust error estimator for a singularly perturbed reaction–diffusion problem. In contrast to conventional estimators, our proposal is suitable for anisotropic finite element...
Robust local problem error estimation for a singularly perturbed problem on anisotropic finite element meshes
Singularly perturbed problems often yield solutions with strong directional features, e.g. with boundary layers. Such anisotropic solutions lend themselves to adapted, anisotropic discretizations. The quality of the corresponding numerical solution is a key issue in any computational simulation. To this end we present a new robust error estimator for a singularly perturbed reaction-diffusion problem. In contrast to conventional estimators, our proposal is suitable for anisotropic finite element...