Search for dissertations about: "singular distribution functions"

Showing result 1 - 5 of 10 swedish dissertations containing the words singular distribution functions.

2. 1. Asymptotics of random matrices and matrix valued processes

   Author : Stefan Israelsson; Kurt Johansson; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Random matrices; singular interaction; spectral distribution; fluctuation limit; distribution valued processes; MATEMATIK; MATHEMATICS; MATEMATIK; matematisk statistik; Mathematical Statistics;

   Abstract : This thesis contains three parts. In the first two papers we consider spectral properties of symmetric matrices with elements consisting of independent Ornstein Uhlenbeck processes. The eigenvalues behave as a particle system on the real line with singular interaction consisting of electrostatic repulsion and a linear restoring force. READ MORE

4. 2. Topics in multifractal measures, nonparametrics and biostatistics

   Author : Attila Frigyesi; Anestesiologi och intensivvård; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; confidence interval; mixed effects; Statistics; operations research; programming; actuarial mathematics; Statistik; operationsanalys; programmering; aktuariematematik; operational model of pharmacological agonism; concentration-response curves; dose-response curves; ventilation perfusion scintigraphy; V Q-scan; pulmonary embolism; automated method; box counting; correlation dimension; Hentschel-Procaccia dimension; Rényi dimension; generalized dimensions; fractal dimension estimation; dimension spectrum; multifractal measures; kernel density estimates; absolute continuity; singular distribution functions;

   Abstract : This thesis consists of four papers. The first two papers, which comprise the main part of the thesis, deal with an unexpected connection between kernel density estimators and dimension spectra for multifractal measures. READ MORE

5. 3. Spectra of elliptic operators and applications

   Author : Medet Nursultanov; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Helmholtz and Maxwell s equations; functional calculus; electromagnetic waveguide; acoustic waveguide; Sturm-Liouville operator; singular potential; asymptotics of eigenvalues; point interactions.;

   Abstract : In this thesis we consider several problems related to elliptic equations. Namely, we investigate Helmholtz and Maxwell's equations in Paper I and Sturm-Liouville spectral problem in Papers II,III. In Paper I we study time-harmonic electromagnetic and acoustic waveguide, modeled by an in�nite cylinder with a non-smooth cross section. READ MORE

6. 4. Spectral properties of elliptic operators in singular settings and applications

   Author : Medet Nursultanov; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : The present thesis is focused on the investigation of the spectral properties of the linear elliptic operators in the presence of singularities. It is divided into three chapters. In the first chapter, we consider geometric singularities. READ MORE

7. 5. On Monte Carlo Operators for Studying Collisional Relaxation in Toroidal Plasmas

   Author : Qaisar Mukhtar; Torbjörn Hellsten; Tainia Kurki-Suonio; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fusion plasma; thermonuclear fusion; tokamak; Coulomb collisions; stochastic differential equations with singular diffusion coefficients; Monte Carlo schemes; spatial diffusion; modelling; Fokker-Planck equation; RF-heating.;

   Abstract : This thesis concerns modelling of Coulomb collisions in toroidal plasma with Monte Carlo operators, which is important for many applications such as heating, current drive and collisional transport in fusion plasmas. Collisions relax the distribution functions towards local isotropic ones and transfer power to the background species when they are perturbed e. READ MORE