Search for dissertations about: "distribution calculation"

Showing result 1 - 5 of 148 swedish dissertations containing the words distribution calculation.

  2. 1. A Detailed Kinetic Model for Calculation of the Soot Particle Size Distribution Function

    Author : Fikret Saric; Förbränningsfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Gaser; fluiddynamik; plasma; Motors and propulsion systems; Motorer; framdrivningssystem; plasmas; fluid dynamics; Gases; Fysik; Physics; Computational Fluid Dynamics; Sectional Method; Method of Moments; Diesel Like Engine Condition; Distribution Function; Detailed Kinetic Soot Model; Soot Particle Size;

    Abstract : The soot particle size distribution was studied via numerical simulation under diesel like engine conditions using a detailed kinetic soot model. Two different mathematical methods of the soot model description have been used in this work. In the first part of the work, the method of moments is presented. READ MORE

  4. 2. Developing and evaluating dose calculation models for verification of advanced radiotherapy

    Author : Jörgen Olofsson; Mikael Karlsson; Anders Ahnesjö; Crister Ceberg; Umeå universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Radiation therapy; high-energy photons; dose calculation; multi-source model; pencil kernel; uncertainties; action levels; Radiological physics; Radiofysik;

    Abstract : A prerequisite for modern radiotherapy is the ability to accurately determine the absorbed dose (D) that is given to the patient. The subject of this thesis has been to develop and evaluate efficient dose calculation models for high-energy photon beams delivered by linear accelerators. READ MORE

  5. 3. Development and evaluation of an independent system for absorbed dose calculations in radiotherapy

    Author : Stefan Johnsson; Lund Medicinsk strålningsfysik; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; medicinsk instrumentering; tomografi; radiologi; Klinisk fysiologi; tomography; medical instrumentation; radiology; Clinical physics; cancer; Cytologi; onkologi; cancerology; oncology; Cytology; PDA; mini-phantom; in-air equivalence; primary kerma; transmission measurement; stopping power ratio; entrance dose; beam quality; quality control; error prevention; monitor unit calculation; radiation therapy; dose calculation;

    Abstract : The aim of this work was to develop, implement and evaluate an independent system with which to calculate the absorbed dose, delivered by high-energy X-ray beams, to the prescription point and the depth of dose maximum. The introduction of such a system in the clinical routine may help ensure high-quality treatment and avoidance of errors which may jeopardise the clinical outcome of the treatment (i. READ MORE

  6. 4. Calculation and Measurement Methods for the Performance of Solar Collectors. Models of Flat Plate Collectors, Transparent Insulation and Efficiency Factors

    Author : Bengt Hellström; Avdelningen för Energi och byggnadsdesign; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transparent insulation; Test method; Calculation method; Concentrating collector; Efficiency factor; Fin efficiency; Flat plate collector; Heat conductivity; Honeycomb; Measurement method; Performance; Solar transmittance; Solar collector; Collector model; Energy research; Energiforskning;

    Abstract : This thesis deals with models of flat plate collectors, transparent insulation and efficiency factors. An equation for the energy output from a glazed flat plate collector is derived by modelling the collector efficiency factor, F´ as the sum of a constant and a temperature dependent part. READ MORE

  7. 5. Absorbed Dose Determination and Characteristics of Degraded Electron Beams: Application to Intraoperative Radiation Therapy

    Author : Peter Björk; Internmedicin - epidemiologi; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Clinical physics; radiology; tomography; medical instrumentation; Klinisk fysiologi; radiologi; tomografi; medicinsk instrumentering; absorbed dose distribution; output factor; stopping-power ratio; beam characteristics; Monte Carlo calculation; electron beam dosimetry; applicator system; radiation therapy; linear accelerator; intraoperative radiotherapy;

    Abstract : The aim of this work was to quantify limitations of and uncertainties in commonly used dosimetric techniques for relative absorbed dose determination in degraded electron beams, such as those encountered in intraoperative radiation therapy (IORT) and small-electron-field radiotherapy. Three different detector types were investigated with regard to measurements of output factors and relative absorbed dose distributions: (1) a parallel-plate ionization chamber, (2) a p-type silicon diode detector and (3) a diamond detector. READ MORE