Sökning: "rotation axis"

Visar resultat 1 - 5 av 54 avhandlingar innehållade orden rotation axis.

  1. 1. Ventricular rotation and the rotation axis : a new concept in cardiac function

    Författare :Ulf Gustafsson; Anders Waldenström; Per Lindqvist; Alan Fraser; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Left ventricular function; right ventricular function; rotation; twist; rotation axis; transition plane; ischemia; speckle tracking echocardiography; Cardiology; Kardiologi; Cardiology; kardiologi;

    Sammanfattning : Background: The twisting motion of the left ventricle (LV), with clockwise rotation at the base and counter clockwise rotation at the apex during systole, is a vital part of LV function. Even though LV rotation has been studied for decades, the rotation pattern has not been described in detail. LÄS MER

  2. 2. Extending the nuclear cranking model to tilted axis rotation and alternative mean field potentials

    Författare :Peter Olivius; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; classical mechanics; gravitation; statistical physics; Kärnfysik; Nuclear physics; kvantmekanik; relativitet; statistisk fysik; termodynamik; thermodynamics; klassisk mekanik; Matematisk och allmän teoretisk fysik; Nuclear Structure; Tilted axis rotation; Mathematical and general theoretical physics; quantum mechanics; relativity; Fysicumarkivet A:2004:Olivius;

    Sammanfattning : The nuclear model for three dimensional cranking is extended to include a generalization of the Strutinski renormalization procedure from principal axis cranking to cranking about an tilted axis. A new computer code has been written for realistic, full-scale calculations within the three dimensional cranking model. LÄS MER

  3. 3. The Dynamical Spin Vector Evolution of the Asteroids

    Författare :Erik Skoglöv; Karri Muinonen; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; asteroids; Eros; Ceres; Vesta; dynamics; rotation; rotational dynamics; orbits; resonances; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik; astronomi; Astronomy;

    Sammanfattning : The dynamical evolution of the spin axis direction due to gravitational and thermal factors is examined. It is found that the spin axis variations generally are regular and relatively small for the bodies in the asteroid main belt. There are also reasons to believe that this is the case for minor objects beyond the main belt. LÄS MER

  4. 4. Direct Driven Generators for Vertical Axis Wind Turbines

    Författare :Sandra Eriksson; Hans Bernhoff; Mats Leijon; Jörgen Blennow; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; synchronous generator; wind power; vertical axis wind turbine; simulations; experiments; finite element method; Engineering physics; Teknisk fysik;

    Sammanfattning : Wind power is a renewable energy source that is increasingly used all over the world. Most wind turbines have a horizontal axis of rotation but a few have a vertical axis of rotation. The concept presented in this thesis is a straight-bladed vertical axis wind turbine with a direct driven cable-wound permanent magnet synchronous generator. LÄS MER

  5. 5. Biomechanical assessment of head and neck movements in neck pain using 3D movement analysis

    Författare :Helena Grip; Gertjan Ettema; Umeå universitet; []
    Nyckelord :movement analysis; kinematics; helical axis; neck pain; whiplash; cervical spine; pattern classification; motor control; head-eye co-ordination; head movement; biomedicinsk strålningsvetenskap; Biomedical Radiation Science;

    Sammanfattning : Three-dimensional movement analysis was used to evaluate head and neck movement in patients with neck pain and matched controls. The aims were to further develop biomechanical models of head and neck kinematics, to investigate differences between subjects with non-specific neck pain and whiplash associated disorders (WAD), and to evaluate the potential of objective movement analysis as a decision support during diagnosis and follow-up of patients with neck pain. LÄS MER