Search for dissertations about: "NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Plasmafysik"

Showing result 1 - 5 of 42 swedish dissertations containing the words NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Plasmafysik.

  1. 1. Solitary waves and enhanced incoherent scatter ion lines

    University dissertation from Kiruna : Institutet för rymdfysik, Umeå universitet

    Author : Jonas Ekeberg; Umeå universitet.; [2011]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; plasma waves and instabilities; nonlinear phenomena; solitons and solitary waves; ionosphere; Sun: corona; incoherent scatter radar; MHD; plasmavågor och instabiliteter; ickelinjära fenomen; solitoner och solitära vågor; jonosfär; solen: korona; inkoherent spridningsradar; MHD; NATURAL SCIENCES Physics Geocosmophysics and plasma physics; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik; NATURAL SCIENCES Physics Geocosmophysics and plasma physics Space physics; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Rymdfysik; NATURAL SCIENCES Physics Geocosmophysics and plasma physics Plasma physics; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Plasmafysik; NATURAL SCIENCES Physics Other physics Non-linear dynamics; chaos; NATURVETENSKAP Fysik Övrig fysik Icke-linjär dynamik; kaos; fysik; Physics; rymd- och plasmafysik; Space and Plasma Physics;

    Abstract : This thesis addresses solitary waves and their significance for auroral particle acceleration, coronal heating and incoherent scatter radar spectra. Solitary waves are formed due to a balance of nonlinear and dispersive effects. READ MORE

  2. 2. Gravitational perturbations in plasmas and cosmology

    University dissertation from Umeå : Institutionen för Fysik

    Author : Mats Forsberg; Umeå universitet.; [2010]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; general relativity; cosmology; gravitational waves; plasma; electromagnetic waves; nonlinear waves; NATURAL SCIENCES Physics Geocosmophysics and plasma physics Plasma physics; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Plasmafysik; NATURAL SCIENCES Physics Other physics Theory of relativity; gravitation; NATURVETENSKAP Fysik Övrig fysik Relativitetsteori; gravitation; NATURAL SCIENCES Physics Astronomy and astrophysics Cosmology; NATURVETENSKAP Fysik Astronomi och astrofysik Kosmologi; teoretisk fysik; Theoretical Physics;

    Abstract : Gravitational perturbations can be in the form of scalars, vectors or tensors. This thesis focuses on the evolution of scalar perturbations in cosmology, and interactions between tensor perturbations, in the form of gravitational waves, and plasma waves. READ MORE

  3. 3. Multi-spectral analysis of fine scale aurora

    University dissertation from Stockholm : KTH

    Author : Hanna Dahlgren; KTH.; [2010]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURAL SCIENCES Physics Geocosmophysics and plasma physics Plasma physics; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Plasmafysik; NATURAL SCIENCES Physics Other physics Optics; NATURVETENSKAP Fysik Övrig fysik Optik;

    Abstract : The Aurora Borealis is the visible manifestation of the complex plasma interaction between the solar wind and the Earth's magnetosphere and ionosphere. Ground based and in situ measurements demonstrate a prevalence of dynamic fine structure within auroral displays, with spatial scales down to tens of metres and time variations occurring on a fraction of a second. READ MORE

  4. 4. Neural Networks Applications and Electronics Development for Nuclear Fusion Neutron Diagnostics

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Emanuele Ronchi; Uppsala universitet.; [2009]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Neural networks; tomography; unfolding; real time; pulse shape discrimination; PSD; neutron spectroscopy; MPRu; TOFOR; KN3; neutron camera; LED; summing amplifiers; electronics; JET; NATURAL SCIENCES Physics Geocosmophysics and plasma physics Plasma physics; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Plasmafysik; NATURAL SCIENCES Physics Other physics Computational physics; NATURVETENSKAP Fysik Övrig fysik Beräkningsfysik; Applied Nuclear Physics; Tillämpad kärnfysik; Elektronik; Electronics;

    Abstract : This thesis describes the development of electronic modules for fusion neutron spectroscopy as well as several implementations of artificial neural networks (NN) for neutron diagnostics for the Joint European Torus (JET) experimental reactor in England.The electronics projects include the development of two fast light pulser modules based on Light Emitting Diodes (LEDs) for the calibration and stability monitoring of two neutron spectrometers (MPRu and TOFOR) at JET. READ MORE

  5. 5. Diagnosing Fuel Ions in Fusion Plasmas using Neutron Emission Spectroscopy

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Carl Hellesen; Uppsala universitet.; [2010]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; fusion; plasma diagnostics; neutron spectroscopy; NBI heating; ICRF heating; energetic ions; NATURAL SCIENCES Physics Geocosmophysics and plasma physics Fusion; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Fusion; NATURAL SCIENCES Physics Nuclear physics; NATURVETENSKAP Fysik Kärnfysik; Applied Nuclear Physics; Tillämpad kärnfysik;

    Abstract : Neutron emission spectra, measured with the time of flight spectrometer TOFOR, at the joint European torus (JET) are presented in this thesis. TOFOR has been in use since 2005, routinely measuring the neutron emission from JET plasmas. READ MORE