Sökning: "a posteriori error estimates"

Visar resultat 26 - 30 av 35 avhandlingar innehållade orden a posteriori error estimates.

1. 26. Adaptive Finite Element Methods for Optimal Control Problems

   Författare :Karin Kraft; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; finite element method; discontinuous Galerkin method; optimal control; a posteriori error estimate; dual weighted residual; adaptive; multilevel algorithm; Newton method; control constraint; variational inequality; vehicle dynamics.;

   Sammanfattning : In this thesis we study the numerical solution of optimal control problems. The problems considered consist of a system of differential equations, the state equations, which are governed by a control variable. The goal is to determine the states and controls which minimize a given cost functional. LÄS MER

3. 27. Adaptive Finite Element Methods for Optimal Control Problems

   Författare :Karin Kraft; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; dual weighted residual; adaptive; Newton method; variational inequality; vehicle dynamics.; multilevel algorithm; discontinuous Galerkin method; a posteriori error estimate; finite element method; optimal control; control constraint;

   Sammanfattning : In this thesis we study the numerical solution of optimal control problems. The problems considered consist of a systemof differential equations, the state equations, which are governed bya control variable. The goal is to determine the states and controls which minimize a given cost functional. LÄS MER

4. 28. Computational Characterization of Mixing in Flows

   Författare :Erik D. Svensson; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; mixing; hyperbolicity; shadowing; finite elements; flow simulation; a priori error estimates; Stokes equations; point location; multigrid; refinements; mixing;

   Sammanfattning : The major theme of this thesis is mathematical aspects of fluid mixing in the case when diffusion is negligible, which is commonly refered to as ’mixing by stirring’ or ’mixing by chaotic advection’ in the engineering literature. In this case the mixing is driven by a velocity field and is characterized by the flow generated by the velocity field. LÄS MER

5. 29. Adaptive Finite Element Methods for the Reynolds Thin Film Model with Cavitation

   Författare :Bertil Nilsson; Sweden Gothenburg Chalmers University of Technology Department of Applied Mechanics; []
   Nyckelord :tribology; Reynolds equation; cavitation; FEM; adaptivity; variational inequality; penalty formulation; error estimation; residual; duality;

   Sammanfattning : The main purpose of this thesis is to use modern goal-oriented adaptive finite element techniques in order to improve the numerical simulation of tribology. Two novel adaptive finite element methods for the Reynolds thin film model including cavitation are presented and their different strategies are compared. LÄS MER

7. 30. State Estimation for Distributed and Hybrid Systems

   Författare :Peter Alriksson; Institutionen för reglerteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Joint Maximum a Posteriori Estimation; Sensor Networks; Distributed State Estimation; Networked Embedded Systems; Markov Jump Linear Systems; Sensor Scheduling;

   Sammanfattning : This thesis deals with two aspects of recursive state estimation: distributed estimation and estimation for hybrid systems. In the first part, an approximate distributed Kalman filter is developed. Nodes update their state estimates by linearly combining local measurements and estimates from their neighbors. LÄS MER