Search for dissertations about: "mirror instability."

Found 5 swedish dissertations containing the words mirror instability..

2. 1. Drift and Mirror Modes in Magnetized Plasmas

   Author : Ingmar Sandberg; Padma Shukla; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; tokamak plasma; drift waves; space plasma; mirror instability.; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik; Space and Plasma Physics; rymd- och plasmafysik;

   Abstract : Low frequency plasma instabilities driven by plasma inhomogeneity and velocity anisotropies are major candidates for the explanation of various phenomena observed in fusion and space plasmas. For low-β fusion plasma, the influence of plasma rotation and finite ion temperature on the structure and the type of toroidal drift eigenmodes in tokamaks is investigated rigorously, including the effects induced by the toroidal geometry such as the coupling mode, the radial variation of plasma rotation velocity and the magnetic shear. READ MORE

4. 2. Peripheral Vision : Adaptive Optics and Psychophysics

   Author : Robert Rosén; Peter Unsbo; Larry Thibos; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : This thesis is about our peripheral vision. Peripheral vision is poor compared to central vision, due to both neural and optical factors. The optical factors include astigmatism, defocus and higher order aberrations consisting mainly of coma. Neurally, the density of ganglion cells decreases towards the periphery, which limits the sampling density. READ MORE

5. 3. On late complications with HA coated hip arthroplasties

   Author : Magne Røkkum; Göteborgs universitet; []
   Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; hip arthroplasty; hydroxyapatite; wear; osteolysis; loosening; clinical; radiological and histological examination;

   Abstract : 100 hips in 86 patients were operated with a total hip arthroplasty entirely coated with a 155±35 µm thick HA coating, and included in a clinical and radiological follow-up study. The female/male ratio was 75/25, and the mean age was 56 years (32-73). Early clinical results were excellent, especially pain relief. No thigh pain was found. READ MORE

6. 4. Properties of Volume Bragg Gratings and Nonlinear Crystals for Laser Engineering

   Author : Staffan Tjörnhammar; Fredrik Laurell; Valdas Pasiskevicius; Takunori Taira; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; volume Bragg grating; VBG; thermal effects; nonlinear optics; KTiOPO4; quasi-phase matching; photochromic damage; grey-tracking; color centers; blue-light induced infrared absorption; BLIIRA; Physics; Fysik;

   Abstract : This thesis focuses on two topics: thermal limitations of volume Bragg gratings (VBGs) employed as laser-cavity mirrors and formation of color centers in KTiOPO4 and its isomorphs.To explore the mechanisms of the thermal limitations of VBGs in high power lasers, I designed and constructed a diode-pumped, solid‑state laser with a VBG as cavity mirror that had a significantly higher absorption than what is typical. READ MORE

7. 5. Development of Time Resolved Laser Imaging Techniques for Studies of Turbulent Reacting Flows

   Author : Johan Hult; Förbränningsfysik; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Electronics and Electrical technology; Laserteknik; Elektronik och elektroteknik; Laser technology; Fysik; Physics; Three-dimensional; Laser Diagnostics; High speed; Fysicumarkivet A:2002:Hult;

   Abstract : In the present thesis the development and application of a novel laser diagnostic system for high speed spectroscopic imaging of turbulent combustion phenomena is presented. The system is capable of recording sequences of up to 8 images with a separation between consecutive images as short as microseconds. READ MORE