Sökning: "numerisk analys"

Visar resultat 1 - 5 av 422 avhandlingar innehållade orden numerisk analys.

1. 1. Adaptive time-integration for goal-oriented and coupled problems

   Författare :Peter Meisrimel; Numerisk analys; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; time-adaptivity; goal-oriented problems; error estimation; coupled problems; waveform relaxation; asynchronous methods; conjugate heat transfer;

   Sammanfattning : We consider efficient methods for the partitioned time-integration of multiphysics problems, which commonly exhibit a multiscale behavior, requiring independent time-grids. Examples are fluid structure interaction in e.g., the simulation of blood-flow or cooling of rocket engines, or ocean-atmosphere-vegetation interaction. LÄS MER

3. 2. Numerical algorithms for high dimensional integration with application to machine learning and molecular dynamics

   Författare :Aku Kammonen; Anders Szepessy; Markos Katsoulakis; KTH; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Numerical Analysis; Numerisk analys;

   Sammanfattning : This thesis contains results on high dimensional integration with two papers, paper I and paper II, presenting applications in machine learning and two papers, paper III and paper IV, presenting applications to molecular dynamics.In paper I we present algorithms based on a Metropolis test for training shallow neural networks with trigonometric activation functions. LÄS MER

4. 3. Krylov methods for nonlinear eigenvalue problems and matrix equations

   Författare :Giampaolo Mele; Elias Jarlebring; Raf Vandebril; KTH; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Numerical Analysis; Numerisk analys;

   Sammanfattning : Nonlinear eigenvalue problems (NEPs) arise in many fields of science and engineering. Such problems are often defined by large matrices, which have specific structures, such as being sparse, low-rank, etc. Like the linear eigenvalue problem, the eigenvector appears in a linear form, whereas the eigenvalue appears in a nonlinear form. LÄS MER

5. 4. Boundary integral methods for fast and accurate simulation of droplets in two-dimensional Stokes flow

   Författare :Sara Pålsson; Anna-Karin Tornberg; Shravan Veerapaneni; KTH; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Numerical Analysis; Numerisk analys;

   Sammanfattning : Accurate simulation of viscous fluid flows with deforming droplets creates a number of challenges. This thesis identifies these principal challenges and develops a numerical methodology to overcome them. Two-dimensional viscosity-dominated fluid flows are exclusively considered in this work. LÄS MER

7. 5. Free Boundary Problems of Obstacle Type, a Numerical and Theoretical Study

   Författare :Mahmoudreza Bazarganzadeh; Henrik Shahgholian; John King; Uppsala universitet; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Partial differential equations; Numerical analysis; Free boundary problems; Mathematics; Matematik;

   Sammanfattning : This thesis consists of five papers and it mainly addresses the theory and schemes to approximate the quadrature domains, QDs. The first deals with the uniqueness and some qualitative properties of the two QDs. The concept of two phase QDs, is more complicated than its one counterpart and consequently introduces significant and interesting open. LÄS MER