Sökning: "datorsimuleringar"

Visar resultat 1 - 5 av 66 avhandlingar innehållade ordet datorsimuleringar.

  1. 1. Theoretical Atomic Spectroscopy of Earthbound and Stellar Plasma

    Författare :Jon Grumer; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; atomstruktur; atomära processer; elektronkorrelation; plasmaspektroskopi; magnetfält; hyperfinstruktur; solkoronan; rymdväder; förekomst av grundämnen i stjärnor; datorsimuleringar; Zeemaneffekt; relativistiska effekter; atomic structure; atomic processes; computer simulation; electron correlation; relativistic atomic theory; plasma spectroscopy; Zeeman effect; magnetic fields; hyperfine structure; solar corona; space weather; stellar abundances; Fysicumarkivet A:2016:Grumer;

    Sammanfattning : Motivated by spectroscopic analysis of astrophysical and laboratory plasma, this thesis concerns the fundamental structure and spectral properties of atoms and their ions. The multiconfiguration Dirac-Hartree-Fock (MCDHF) method is used to predict the emission or absorption of radiation, by atomic systems in general, and of heavy and highly charged ions in particular. LÄS MER

  3. 2. Optimization of breast tomosynthesis: Computer simulations of image acquisition and glandular dose

    Författare :Hannie Förnvik; Malmö Medicinsk strålningsfysik; []
    Nyckelord :breast tomosynthesis; Monte Carlo simulation; acquisition parameters; software breast phantom; microcalcifications; breast density; glandular dose; glandular distribution;

    Sammanfattning : Breast tomosynthesis (BT) is an X-ray imaging technique recently introduced as an alternative or complement to standard digital mammography (DM) in breast imaging and breast cancer screening. In BT, a set of projection images is acquired over a limited angular range and reconstructed into a volume of slice images. LÄS MER

  4. 3. Charged Polymers: From DNA to Polyampholytes

    Författare :Malek O Khan; Beräkningskemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; computational steering; DNA condensation; ion correlations; electrostatic interactions; colloidal stability; polyampholytes; Monte Carlo simulations; polyelectrolytes; Theoretical chemistry; quantum chemistry; Teoretisk kemi; kvantkemi;

    Sammanfattning : Three main themes are outlined in this thesis: Polyelectrolytes/DNA : In a living cell, DNA molecules have a compact conformation in order to fit in, while in a test tube they will take on an expanded cylindrical shape, due to the negative phosphate groups along the DNA molecule. With the help of computer simulations it has been shown that like-charged monomers of a poly- electrolyte can attract each other if the counterions are taken into account. LÄS MER

  5. 4. Bridge functions in strongly coupled plasmas : theory, simulations and applications

    Författare :Federico Castello Lucco; Svetlana V. Ratynskaia; Panagiotis Tolias; Giorgio Pastore; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Teoretisk fysik; Theoretical Physics; Atomic; Subatomic and Astrophysics; Atomär fysik; subatomär fysik och astrofysik;

    Sammanfattning : Strongly coupled or non-ideal plasmas are multi-component charged systems in which at least one species possesses an average interaction energy that is comparable or larger than its thermal energy. Non-ideal plasmas are naturally occurring in dense astrophysical objects (e.g. giant planet interiors) but also engineered in the laboratory (e. LÄS MER

  7. 5. Network Modelling for Evaluation of Mechanical Properties of Cellulose Fibre Fluff

    Författare :Susanne Heyden; Byggnadsmekanik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hydraulic engineering; Civil engineering; fracture; fibres; computer simulation; offshore technology; soil mechanics; Väg- och vattenbyggnadsteknik;

    Sammanfattning : A network mechanics model for cellulose fibre fluff is proposed. 2D and 3D versions of the model have been implemented and the influence of various micro-level parameters on the global mechanical performance has been determined by means of computer simulations. LÄS MER