Sökning: "Monte-Carlo methods"

Visar resultat 21 - 25 av 391 avhandlingar innehållade orden Monte-Carlo methods.

  1. 21. A Matter of Disorder : Monte Carlo Simulations of Phase Transitions in Strongly Disordered Systems

    Författare :Marios Nikolaou; Mats Wallin; Asle Sudbø; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; phase transitions; disorder; Monte Carlo simulations; superconductivity; Statistical physics; Statistisk fysik;

    Sammanfattning : Phase transitions and their critical scaling properties, especially in systems with disorder, are important both for our theoretical understanding of our environment, but also for their practical use in applications and materials in our everyday life. This thesis presents results from finite size scaling analysis of critical phenomena in systems with disorder, using high-precision Monte Carlo simulations and state of the art numerical methods. LÄS MER

  3. 22. Experimental data and Total Monte Carlo : Towards justified, transparent and complete nuclear data uncertainties

    Författare :Petter Helgesson; Henrik Sjöstrand; Arjan Koning; Stephan Pomp; Dimitri Rochman; Klaes-Håkan Bejmer; Denise Neudecker; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysik med inriktning mot tillämpad kärnfysik; Physics with specialization in Applied Nuclear Physics;

    Sammanfattning : The applications of nuclear physics are many with one important being nuclear power, which can help decelerating the climate change. In any of these applications, so-called nuclear data (ND, numerical representations of nuclear physics) is used in computations and simulations which are necessary for, e.g., design and maintenance. LÄS MER

  4. 23. On Monte Carlo Operators for Studying Collisional Relaxation in Toroidal Plasmas

    Författare :Qaisar Mukhtar; Torbjörn Hellsten; Tainia Kurki-Suonio; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fusion plasma; thermonuclear fusion; tokamak; Coulomb collisions; stochastic differential equations with singular diffusion coefficients; Monte Carlo schemes; spatial diffusion; modelling; Fokker-Planck equation; RF-heating.;

    Sammanfattning : This thesis concerns modelling of Coulomb collisions in toroidal plasma with Monte Carlo operators, which is important for many applications such as heating, current drive and collisional transport in fusion plasmas. Collisions relax the distribution functions towards local isotropic ones and transfer power to the background species when they are perturbed e. LÄS MER

  5. 24. Response Matrix Reloaded : for Monte Carlo Simulations in Reactor Physics

    Författare :Mickus Ignas; Jan Dufek; Jaakko Leppänen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Kärnenergiteknik; Nuclear Engineering;

    Sammanfattning : This thesis investigates Monte Carlo methods applied to criticality and time-dependent problems in reactor physics. Due to their accuracy and flexibility, Monte Carlo methods are considered as a “gold standard” in reactor physics calculations. However, the benefits come at a significant computing cost. LÄS MER

  7. 25. Dose Management in Diagnostic Radiology - application of the DICOM imaging standard and a Monte Carlo dose engine for exposure surveillance

    Författare :Hans-Erik Källman; Anders Ahnesjö; Hilde M. Olerud; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Radiology; metadata; DICOM; radiation safety; Monte Carlo; source model; patient model; optimization; justification; Medicinsk radiofysik; Medical Radiophysics;

    Sammanfattning : Ionizing radiation is used in diagnostic radiology with a large contribution to the health of the patients. The regulations to limit the detrimental effects, e.g. cancer induction, are based on recommendations from the International Commission on Radiological Protection (ICRP). LÄS MER