Search for dissertations about: "David Cohen"

Found 4 swedish dissertations containing the words David Cohen.

2. 1. Exponential integrators for stochastic partial differential equations

   Author : Rikard Anton; David Cohen; Christian Engström; Stig Larsson; Annika Lang; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Stochastic partial differential equations; numerical methods; stochastic exponential integrator; strong convergence; trace formulas;

   Abstract : Stochastic partial differential equations (SPDEs) have during the past decades become an important tool for modeling systems which are influenced by randomness. Because of the complex nature of SPDEs, knowledge of efficient numerical methods with good convergence and geometric properties is of considerable importance. READ MORE

4. 2. Reliable hp finite element computations of scattering resonances in nano optics

   Author : Juan Carlos Araujo-Cabarcas; Christian Engström; David Cohen; Mats G. Larson; Jeffrey Ovall; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Scattering resonances; Helmholtz problems; pseudospectrum; Lippmann-Schwinger equation; finite element methods; nonlinear eigenvalue problems; spurious solutions;

   Abstract : Eigenfrequencies are commonly studied in wave propagation problems, as they are important in the analysis of closed cavities such as a microwave oven. For open systems, energy leaks into infinity and therefore scattering resonances are used instead of eigenfrequencies. READ MORE

5. 3. Numerical analysis and simulation of stochastic partial differential equations with white noise dispersion

   Author : André Berg; David Cohen; Per Åhag; Guillaume Dujardin; Ludovic Goudenège; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; stochastic partial differential equation; mathematics; numerical analysis; numerical scheme; time integrator; convergence analysis; blowup; critical exponent; nonlinear Schrödinger equation; Manakov equation; Benjamin-Bona-Mahony equation; BBM equation; stochastic; random; dispersion; white noise dispersion; finite difference; pseudospectral; code; matlab; exponential integrator; splitting integrator; convergence in probability; Mathematics; matematik; Numerical Analysis; numerisk analys;

   Abstract : This doctoral thesis provides a comprehensive numerical analysis and exploration of several stochastic partial differential equations (SPDEs). More specifically, this thesis investigates time integrators for SPDEs with white noise dispersion. READ MORE

6. 4. Aspects of a Constraint Optimisation Problem

   Author : Johan Thapper; Peter Jonsson; David Cohen; Linköpings universitet; []
   Keywords : TECHNOLOGY; TEKNIKVETENSKAP;

   Abstract : In this thesis we study a constraint optimisation problem called the maximum solution problem, henceforth referred to as Max Sol. It is defined as the problem of optimising a linear objective function over a constraint satisfaction problem (Csp) instance on a finite domain. READ MORE