Sökning: "Boltzmann equation"

Visar resultat 21 - 25 av 38 avhandlingar innehållade orden Boltzmann equation.

  1. 21. Biomedical and atmospheric applications of optical spectroscopy in scattering media

    Författare :Johannes Swartling; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Turbid media; Tissue optics; Tissue optical properties; Multiple scattering; Radiative transfer; Diffusion equation; Monte Carlo method; Time-resolved spectroscopy; Atomic and molecular physics; Integrating spheres; Atom- och molekylärfysik; Fysicumarkivet A:2002:Swartling;

    Sammanfattning : Spectroscopic analysis of scattering media is difficult because the effective path length of the light is non-trivial to predict when photons are scattered many times. The main area of research for such conditions is biological tissues, which scatter light because of variations of the refractive index on the cellular level. LÄS MER

  3. 22. Computational framework for studying charge transport in high-voltage gas-insulated systems

    Författare :Shailendra Singh; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; barrier discharge; low temperature plasma; drift diffusion equation; gaseous dielectrics; gas discharge; streamer propagation; high voltage;

    Sammanfattning : Electrical switchgear industry dealing with transmission and distribution of power is strongly affected by the changing dynamics of climate control. Their main contribution to the global warming is through SF6 gas, having a GWP of 23500 (times of CO2). SF6 plays an important role in providing electrical insulation for these high voltage systems. LÄS MER

  4. 23. A Differentiable Approach to Stochastic Differential Equations : the Smoluchowski Limit Revisited

    Författare :Haidar Al-Talibi; Astrid Hilbert; Yaozhong Hu; Linnéuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; α-stable Lévy noise; Fractional Brownian motion; Girsanov theorem; Mean-field model; Nonlinear stochastic oscillator; Ornstein-Uhlenbeck process; Scaling limit; Second order Itô equation; Time change.; Matematik; Mathematics;

    Sammanfattning : In this thesis we generalize results by Smoluchowski [43], Chandrasekhar[6], Kramers, and Nelson [30]. Their aim is to construct Brownian motion as a limit of stochastic processes with differentiable sample paths by exploiting a scaling limit which is a particular type of averaging studied by Papanicolao [35]. LÄS MER

  5. 24. On Lorentz Invariance, Regularity and Global Existence for Kinetic Equations

    Författare :Håkan Andreasson; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : [A1] Regularity of the gain term and strong L1 convergence to equilibrium for the relativistic Boltzmann equation. The main purpose of the paper is to show that the gain term of the relativistic collision operator is regularizing. This is a generalization of P.L. LÄS MER

  7. 25. Thermoelectric phenomena in low-dimensional semiconductor systems

    Författare :Magnus Larsson; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; kvantmekanik; relativitet; gravitation; statistisk fysik; termodynamik; Semiconductory physics; Halvledarfysik; thermopower anomaly; thermoelectricity; thermionic couple; zone-folding; cool chip; ballistic; thermionic; Mathematical and general theoretical physics; Matematisk och allmän teoretisk fysik; thermodynamics; statistical physics; relativity; quantum mechanics; klassisk mekanik; classical mechanics;

    Sammanfattning : This thesis investigates thermoelectric effects, predominantly in low-dimensional semiconductors. Various novel phenomena are predicted, investigated and discussed. LÄS MER