Search for dissertations about: "Natural Sciences Physical Sciences Astronomy"

Showing result 21 - 25 of 487 swedish dissertations containing the words Natural Sciences Physical Sciences Astronomy.

  2. 21. Solar Wind and Geomagnetic Activity - Predictions Using Neural Networks

    Author : Hans Gleisner; Astronomi - Genomgår omorganisation; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Geophysics; kosmisk kemi; rymdvetenskap; magnetosphere; solar wind; space weather; geomagnetic activity; geomagnetism; ring current; auroral electrojet; neural networks; forecasting; Astronomy; space research; Astronomi; cosmic chemistry; physical oceanography; meteorology; Geofysik; fysisk oceanografi; meteorologi; Fysicumarkivet A:2000:Gleisner;

    Abstract : This thesis shows how artificial neural networks (ANNs) can be applied to predict geomagnetic activity from solar-wind data. It introduces and summarizes five papers where development of ANN models are reported, and where predictions of geomagnetic activity are discussed. READ MORE

  4. 22. Space Weather Physics: Dynamic Neural Network Studies of Solar Wind-Magnetosphere Coupling

    Author : Jian-Guo Wu; Astronomi - Genomgår omorganisation; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Geophysics; kosmisk kemi; rymdvetenskap; Astronomi; cosmic chemistry; solar wind; space weather; magnetosphere; solar wind-magnetosphere coupling; geomagnetic activity; geomagnetic storms; predictions; modeling; neural networks; space research; Astronomy; physical oceanography; meteorology; Geofysik; fysisk oceanografi; meteorologi; Fysicumarkivet A:1997:Wu;

    Abstract : This thesis presents studies of solar wind-magnetosphere coupling using dynamic neural networks in combination with statistically correlative analysis. The primary contribution of the thesis is dynamic neural network models that can be implemented for near real-time predictions of geomagnetic storms from the solar wind alone. READ MORE

  5. 23. Star Formation and feedback at key physical scales for galaxy evolution

    Author : Lorenza Della Bruna; Angela Adamo; Göran Östlin; Monica Relaño Pastor; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Galaxies; Star Formation; Stellar Feedback; HII regions; ISM; Astronomy; astronomi;

    Abstract : Feedback from young, massive stars plays an essential role in the self-regulation of star formation in galaxies, and in shaping the galaxies' global properties. This phenomenon originates at small scales, surrounding the stars, but has been observed to be effective up to galactic-wide scales. READ MORE

  6. 24. Spectral and Temporal Studies of Gamma-Ray Bursts

    Author : Luis Borgonovo; Claes-Ingvar Björnsson; Jerry Fishman; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy and astrophysics; Astronomi och astrofysik; Astronomy; astronomi;

    Abstract : Gamma-ray bursts (GRBs) are sporadic flashes of light observed primarily in the gamma-ray band. Being the brightest explosions in the Universe since its birth, they are at present also the furthest astronomical sources detected. READ MORE

  7. 25. Thermal physics of asteroids

    Author : Johan S. V. Lagerros; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; asteroids; infrared emission; thermophysical models; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik; astronomi; Astronomy;

    Abstract : The thermal infrared and microwave emission from asteroids have many applications. Fundamental physical properties can be investigated, which have implications for the geophysical evolution of the asteroids, and the early history of the solar system.A new thermophysical model of asteroids is presented. READ MORE