Sökning: "volume effect"

Visar resultat 1 - 5 av 895 avhandlingar innehållade orden volume effect.

  1. 1. Intracranial volume in neuroimaging: estimation and use in regional brain volume normalization

    Författare :Niklas Klasson; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; magnetic resonance imaging; intracranial volume; normalization;

    Sammanfattning : The aim of this thesis is to validate methods for estimation of intracranial volume in magnetic resonance images and to improve our understanding of the effect of intracranial volume normalization. To achieve the first part of the aim, 62 gold standard estimates of intracranial volume were generated by manually segmenting 1. LÄS MER

  3. 2. Free Volume and Mesopores in Polymer Nanocomposites

    Författare :Petra Winberg; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemical technology and engineering; Kompositmaterial; Composite materials; Macromolecular chemistry; permeability ; membrane ; positron annihilation ; fumed silica ; clay ; mesopores ; polymer nanocomposites ; free volume ; Kemiteknik och kemisk teknologi; Makromolekylär kemi;

    Sammanfattning : The free volume in polymers is coupled to several important physical properties, such as density, viscosity and gas diffusivity. The physical properties of polymers close to a solid surface have been shown to be significantly perturbed as compared to their bulk state. LÄS MER

  4. 3. Water diffusion and free volume in hydrophilic polymers

    Författare :Charlotte Trotzig; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; free volume; self-diffusion; degree of crystallinity; glass transition temperature; tensile storage modulus; surface tension; isotherm; HPMC; PEO; water; triacetin; clay; Macromolecular chemistry; dynamic mechanical analysis; Fysikalisk kemi; differential scanning calorimetry; nuclear magnetic resonance; positron annihilation; Makromolekylär kemi;

    Sammanfattning : During moisture uptake in polymers, the diffusion of the water molecules is believed to occur via unoccupied voids. These voids are called free volume cavities and their sizes are continuously altered when the moisture content in the polymer is enhanced. LÄS MER

  5. 4. The Use of the Continuity Factor as a Tool to Represent Representative Elementary Volume in Rock Engineering Design

    Författare :Pin Zhou; Stefan Larsson; Johansson Johansson; Arild Palmström; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rock mass; scale effect; representative elementary volume; continuity factor; Byggvetenskap; Civil and Architectural Engineering;

    Sammanfattning : .... LÄS MER

  7. 5. Radiation Oncology Data and Modelling Side Effects after Radiation Therapy

    Författare :Caroline Olsson; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; dose and side effect data; dose-volume response; fractionation effect; LQ model; sequential two-phase radiotherapy; head and neck cancer; parotid gland; xerostomia; pelvic radiotherapy; gynecological cancer; pubic bone; pain; data integration; xerostomia;

    Sammanfattning : Although modern radiation therapy techniques have the ability to conform the dose distribution of ionizing radiation tightly around the volume to be treated, unwanted irradiation to surrounding organs remains a problem. The probability of a side effect arising in the normal tissue of a patient after radiation therapy can be modelled by sigmoid mathematical functions known as normal tissue complication probability (NTCP) models. LÄS MER