I will present some recent results in the spirit of the De Giorgi-Nash-Moser theory for a wide class of kinetic integral equations, where the diffusion term in velocity is an integro-differential operator having nonnegative kernel of fractional order with merely measurable coefficients. I will mainly focus on boundedness estimates and Harnack inequalities. The talk is based on a series of papers by Anceschi, Kassmann, Piccinini, Weidner and myself.
La douleur psychologique augmente le risque d’idées et d’actes suicidaires et constitue une cible thérapeutique potentielle. Cependant, les mécanismes de la douleur mentale restent flous. Notre étude suggère que les systèmes sérotoninergique et nociceptif sont associés à l’activité du réseau cérébral qui est à l’origine la perception de la douleur mentale au cours de la dépression. La douleur mentale pourrait être une condition nécessaire, mais insuffisante pour l’émergence d’idées suicidaires au cours de la dépression.
Shape optimization involves the minimization of a cost function defined over a shape, often governed by a partial differential equation (PDE). Since analytical solutions are typically unavailable, we need to rely on numerical method to find an approximate solution. The level set method, when coupled with finite element analysis, is one of the most versatile numerical shape optimization approach. However, its reliance on meshing introduces limitations inherent to mesh-based methods.
In this talk, we present a fully meshless level set framework that leverages neural networks to parameterize the level set function and employs the graph Laplacian to solve the underlying PDE. This approach enables precise computation of geometric quantities such as normals and curvature. Furthermore, we exploit the flexibility of neural networks to address optimization problems within the class of convex shapes.