Search for dissertations about: "jun yu"

Showing result 1 - 5 of 9 swedish dissertations containing the words jun yu.

2. 1. Nearest neighbor probability density estimators

   Author : Jun Yu; Bo Ranneby; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; matematisk statistik; Mathematical Statistics;

   Abstract : .... READ MORE

4. 2. Statistical methods in medical image estimation and sparse signal recovery

   Author : Fekadu Lemessa Bayisa; Jun Yu; Ottmar Cronie; Henning Omre; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Computed tomography; magnetic resonance imaging; Gaussian mixture model; skew-Gaussian mixture model; hidden Markov random field; hidden Markov model; supervised statistical learning; synthetic CT images; pseudo-CT images; spike and slab prior; adaptive algorithm;

   Abstract : This thesis presents work on methods for the estimation of computed tomography (CT) images from magnetic resonance (MR) images for a number of diagnostic and therapeutic workflows. The study also demonstrates sparse signal recovery method, which is an intermediate method for magnetic resonance image reconstruction. READ MORE

5. 3. Data-driven quality management using explainable machine learning and adaptive control limits

   Author : Niklas Fries; Patrik Rydén; Jun Yu; Rebecka Jörnsten; Umeå universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; quality management; machine learning; local explanation methods; process adjustment policies; simulation; matematisk statistik; Mathematical Statistics; data science; data science;

   Abstract : In industrial applications, the objective of statistical quality management is to achieve quality guarantees through the efficient and effective application of statistical methods. Historically, quality management has been characterized by a systematic monitoring of critical quality characteristics, accompanied by manual and experience-based root cause analysis in case of an observed decline in quality. READ MORE

6. 4. Biotic resistance in freshwater fish communities

   Author : Anna Henriksson; Göran Englund; David Wardle A.; Jun Yu; Sebastian Diehl; Donald Jackson; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; biotic resistance; freshwater fish; introductions; invasions; invasion success; invasibility; invasiveness; species richness; saturation; species identity; weighted species richness;

   Abstract : Invasions of non-native species cause problems in ecosystems worldwide, and despite the extensive effort that has been put into research about invasions, we still lack a good understanding for why some, but not other, communities resist these invasions. In this doctoral thesis I test hypotheses on biotic resistance using a large dataset of more than 1000 both failed and successful introductions of freshwater fish into Swedish lakes. READ MORE

7. 5. The PET sampling puzzle : intelligent data sampling methods for positron emission tomography

   Author : Klara Leffler; Jun Yu; Ida Häggström; Zhiyong Zhou; Saikat Chatterjee; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; sparse signal processing; compressed sensing; Poisson denoising; positron emission tomography PET ; sinogram denoising; sinogram inpainting; deep learning; matematisk statistik; Mathematical Statistics;

   Abstract : Much like a backwards computed Sudoku puzzle, starting from the completed number grid and working ones way down to a partially completed grid without damaging the route back to the full unique solution, this thesis tackles the challenges behind setting up a number puzzle in the context of biomedical imaging. By leveraging sparse signal processing theory, we study the means of practical undersampling of positron emission tomography (PET) measurements, an imaging modality in nuclear medicine that visualises functional processes within the body using radioactive tracers. READ MORE