Search for dissertations about: "degenerate parabolic operators"

Found 5 swedish dissertations containing the words degenerate parabolic operators.

2. 1. On parabolic equations of Kolmogorov-Fokker-Planck type

   Author : Malte Litsgård; Kaj Nyström; Ugo Gianazza; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Kolmogorov equation; degenerate parabolic; ultraparabolic; Lipschitz domain; Dirichlet problem; boundary behaviour; parabolic measure.; Mathematics; Matematik;

   Abstract : In this thesis solutions to Kolmogorov-Fokker-Planck type equations are studied. It consists of a comprehensive summary and four scientific articles.In the first article a potential theory for certain strongly degenerate parabolic operators in unbounded domains of Lipschitz type is developed. READ MORE

4. 2. Obstacle Problems for Green Potentials and for Parabolic Quasiminima

   Author : Catarina Petersson; Matematik (naturvetenskapliga fakulteten); []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Functions; differential equations; Funktioner; differentialekvationer; Matematik; degenerate parabolic operators; Mathematics; quasiminima; obstacle problems; Green potentials;

   Abstract : The thesis consists of two parts. In the first part pure potential theoretic methods are employed to study the obstacle problem connected with a uniformly elliptic second-order differential operator in divergence form. Regular points of the obstacles are characterized by the classical Wiener criterion. READ MORE

5. 3. Selected Topics in Mathematical Modelling: Machine Learning and Tugs-of-War

   Author : Carmina Fjellström; Kaj Nyström; Andrea Pascucci; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Machine learning; Neural networks; LSTM; Financial forecasting; Time series analysis; Stochastic gradient descent; Diffusion map; Dimension reduction; Tug-of-war games; Fractional heat operator; Mean value property; Infinity fractional heat operators; Dynamic programming principle; p-Laplacian; Infinity Laplacian; Kolmogorov equation; Stochastic games; Viscosity solutions; Tillämpad matematik och statistik; Applied Mathematics and Statistics;

   Abstract : This thesis concerns selected topics in mathematical modelling, namely in machine learning and stochastic games called tugs-of-war. It consists of four scientific articles. The first and second are about machine learning topics, while the third and fourth articles are about tug-of-war games. READ MORE

6. 4. Some developments of the homogenization theory and related questions

   Author : Jonas Engström; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Matematik;

   Abstract : This thesis is mainly devoted to homogenization theory and it consists of an introduction, five papers and two conference proceedings. The introduction gives an elementary presentation of the basic ideas in homogenization theory, serves as an overview of the field and points out where the results of this thesis fit in. READ MORE

7. 5. Boundary Behavior of p-Laplace Type Equations

   Author : Benny Avelin; Kaj Nyström; Steve Hofmann; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; p-Laplace; Boundary Harnack inequality; A-harmonic; Ahlfors regularity; NTA-domains; Martin boundary; Reifenberg flat; Approximable by Lipschitz graphs; Subelliptic; Carleson estimate; Mathematics; Matematik;

   Abstract : This thesis consists of six scientific papers, an introduction and a summary. All six papers concern the boundary behavior of non-negative solutions to partial differential equations.Paper I concerns solutions to certain p-Laplace type operators with variable coefficients. READ MORE