Sökning: "pressure flow studies"

Visar resultat 1 - 5 av 437 avhandlingar innehållade orden pressure flow studies.

  1. 1. Numerical Studies of Flow and AssociatedLosses in the Exhaust Port of a Diesel Engine

    Författare :Yue Wang; Laszlo Fuchs; Mihai Mihaescu; Angelo Onorati; KTH; []
    Nyckelord :Internal Combustion Engine; Exhaust flow; Exhaust Valve; Exhaust Port; Large Eddy Simulation; Valve and Piston Motion; Total Pressure Losses; Energy Losses; Discharge coefficient; Flow Losses; Flow structures; Air Flow Bench; Engine-like Conditions; SRA - Energy; SRA - Energi;

    Sammanfattning : In the last decades, the focus of internal combustion engine development has moved towards more efficient and less pollutant engines. In a Diesel engine, approximately 30-40% of the energy provided by combustion is lost through the exhaust gases. The exhaust gases are hot and therefore rich of energy. LÄS MER

  3. 2. Studies on sitting pressure and buttock microcirculation : aiming at developing an alarm in the prevention of pressure ulcers in patients with spinal cord injuries

    Författare :Johan Thorfinn; Disa Lidman; Folke Sjöberg; Henry Svensson; Linköpings universitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Blood supply; Buttocks; Hyperemia; Ischemia; Laser-Doppler flowmetry; Microcirculation; Posture physiology; Pressure; Skin blood supply; Medicine; Medicin;

    Sammanfattning : Pressure ulcers in patients with spinal cord injuries are a major problem, the prevalence in this group being reported as high as 20 – 30 percent. Most pressure ulcers develop around the pelvic girdle, and the key-contributing factor in the development of pressure ulcers is ischaemia due to longstanding pressure. LÄS MER

  4. 3. Preventing pressure ulcers by assessment of the microcirculation in tissue exposed to pressure

    Författare :Sara Bergstrand; Margareta Lindgren; Anna-Christina Ek; Maria Engström; Lars-Göran Lindberg; Fredrik Huss; Linköpings universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pressure ulcer; photoplethysmography; laser Doppler flowmetry; non-invasive; tissue blood flow; reactive hyperemia; pressure-induced vasodilation; interface pressure; risk assessment;

    Sammanfattning : The overall aim of this thesis was to combine optical methods into a system with the ability to simultaneously measure blood flow changes at different tissue depths. The goal of such a system was to reveal vascular mechanisms relevant to pressure ulcer etiology under clinically relevant conditions and in relation to the evaluation of pressure-redistribution support surfaces. LÄS MER

  5. 4. Cerebral blood flow and intracranial pulsatility studied with MRI : measurement, physiological and pathophysiological aspects

    Författare :Anders Wåhlin; Anders Eklund; Jan Malm; Richard Birgander; William G Bradley; Umeå universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Arterial Pulsatility; cerebrospinal fluid; cerebral blood flow; venous flow; intracranial pressure; pulse pressure; dementia; hippocampus; multiple sclerosis; magnetic resonance imaging; radiofysik; radiation physics;

    Sammanfattning : During each cardiac cycle pulsatile arterial blood inflates the vascular bed of the brain, forcing cerebrospinal fluid (CSF) and venous blood out of the cranium. Excessive arterial pulsatility may be part of a harmful mechanism causing cognitive decline among elderly. LÄS MER

  7. 5. Unpacking the Flow : Knowledge Transfer in MNCs

    Författare :Magnus Persson; Mats Forsgren; Ulf Andersson; Ram Mudambi; Uppsala universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Business studies; Knowledge transfer; Innovation; Multinational corporations; Technology; Subsidiary; Företagsekonomi; Business studies; Företagsekonomi;

    Sammanfattning : Multinational corporations (MNCs) are increasingly competing on their ability to utilise knowledge sourced from various parts of the world. In order to draw full advantage of a multinational presence, harnessing the potential of peripheral knowledge assets is a main strategic imperative. LÄS MER