Search for dissertations about: "hierarchical sampling"

Showing result 1 - 5 of 21 swedish dissertations containing the words hierarchical sampling.

2. 1. Hierarchical Variance Reduction Techniques for Monte Carlo Rendering

   Author : Petrik Clarberg; Institutionen för datavetenskap; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; computer graphics; Monte Carlo methods; importance sampling; hierarchical techniques; rendering;

   Abstract : Ever since the first three-dimensional computer graphics appeared half a century ago, the goal has been to model and simulate how light interacts with materials and objects to form an image. The ultimate goal is photorealistic rendering, where the created images reach a level of accuracy that makes them indistinguishable from photographs of the real world. READ MORE

4. 2. Effects of Agriculture on Abundance, Genetic Diversity and Fitness in the Common Frog, Rana temporaria

   Author : Markus Johansson; Anssi Laurila; Juha Merilä; Craig R. Primmer; Michael W. Bruford; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Biology; agriculture; agrochemicals; amphibians; effective population size; genetic diversity; genetic structure; hierarchical sampling; microsatellites; Rana temporaria; Biologi; Biology; Biologi;

   Abstract : The aims of this thesis were to evaluate the effects of agriculture on amphibians in terms of (i) population genetic consequences of agriculture-induced spatial changes of the landscape and (ii) local adaptation and tolerance to frequently used agrochemicals. The study was performed using the common frog Rana temporaria as a model. READ MORE

5. 3. Enhanced block sparse signal recovery and bayesian hierarchical models with applications

   Author : Jianfeng Wang; Jun Yu; Anders Garpebring; Jia Li; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Magnetic resonance imaging; Bayesian hierarchical models; Weather Research and Forecasting; Compressive sensing; Block sparsity; Multivariate isotropic symmetric a-stable distribution; q-ratio block constrained minimal singular value;

   Abstract : This thesis is carried out within two projects ‘Statistical modelling and intelligentdata sampling in Magnetic resonance imaging (MRI) and positron-emission tomography(PET) measurements for cancer therapy assessment’ and ‘WindCoE -Nordic Wind Energy Center’ during my PhD study. It mainly focuses on applicationsof Bayesian hierarchical models (BHMs) and theoretical developments ofcompressive sensing (CS). READ MORE

6. 4. Offline and Online Models for Learning Pairwise Relations in Data

   Author : Fazeleh Sadat Hoseini; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Mulit-Armed Bandit; Pairwise Relations; Performance Modeling; Motion Trajectory Clustering; Minimax Distance; Bottleneck Identification; Online Learning; Representation Learning; Memory Efficiency; Concurrent Programming; Thompson Sampling;

   Abstract : Pairwise relations between data points are essential for numerous machine learning algorithms. Many representation learning methods consider pairwise relations to identify the latent features and patterns in the data. This thesis, investigates learning of pairwise relations from two different perspectives: offline learning and online learning. READ MORE

7. 5. Assesing performance of PCR analysis using Bayesian modelling

   Author : Ronny Hedell; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Bayesian; Hierarchical model; PCR; Low-template DNA; Bacillus anthracis; Sensitivity; Forensic science; Forensic science;

   Abstract : Different analytical methods are available to analyse the DNA samples from crime scenes or to screen samples for the presence of some target bacterium. For this purpose a method known as Polymerase Chain Reaction (PCR) can often be used. READ MORE