Sökning: "focused waves"

Visar resultat 6 - 10 av 63 avhandlingar innehållade orden focused waves.

  1. 6. Laser-Driven Plasma Waves for Particle Acceleration and X-ray Production

    Författare :Guillaume Genoud; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Laser plasma acceleration of electrons and protons; laser-wakefield acceleration; plasma waves; plasma-wiggler radiation; betatron radiation; laser guiding; laser pointing stabilisation;

    Sammanfattning : This thesis presents experimental results related to laser plasma accelerators. These rely on very different principles from conventional particle accelerators. LÄS MER

  3. 7. Oblique waves in boundary layer transition

    Författare :Stellan Berlin; KTH; []
    Nyckelord :;

    Sammanfattning : Traditional research on laminar-turbulent transition has focused on scenarios that are caused by the exponential growth of eigensolutions to the linearized disturbance equations, e.g. two-dimensional Tollmien-Schlichting waves. LÄS MER

  4. 8. Guided Elastic Waves along Periodically Corrugated Structures

    Författare :Ahmed M. A. El-Bahrawy; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : The present thesis consider time-harmonic surface and guided elastic waves propagating along periodically corrugated structures. The problems discussed deal with various configurations where the surfaces are sinusoidally - singly or doubly - periodic, and the interest is focused on investigating the roots of the dispersion relations and in particular the stopband and cross-over resonances. LÄS MER

  5. 9. Measurements in Idiopathic Normal Pressure Hydrocephalus : Computerized neuropsychological test battery and intracranial pulse waves

    Författare :Anders Behrens; Jan Malm; Anders Eklund; Eva Elgh; Niklas Lenfeldt; Marianne Juhler; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Hydrocephalus; Normal Pressure; Neuropsychological tests; Neuropsychology; Reliability and validity; Software; Dementia; intracranial pressure; spinal puncture; cerebrospinal fluid pressure; pulse pressure waves; Blood flow velocity; Middle cerebral artery; Pulsatility index; Neurology; neurologi;

    Sammanfattning : Idiopathic Normal Pressure Hydrocephalus (INPH) is a condition affecting gait, cognition and continence. Radiological examination reveals enlarged ventricles of the brain. A shunt that drains CSF from the ventricles to the abdomen often improves the symptoms. LÄS MER

  7. 10. Klassrummets semiotiska resurser : en språkdidaktisk studie av skolämnena hem- och konsumentkunskap, biologi och kemi

    Författare :Anna Maria Hipkiss; Ann-Catrine Edlund; Per-Olof Erixon; Per Holmberg; Umeå universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; HUMANIORA; HUMANITIES; classroom communication; classroom design; educational sociology; secondary school; semiotic resources; semantic waves; social semiotics; SFL; subject-specific language;

    Sammanfattning : This thesis focuses on how different semiotic resources, such as spoken and written texts, artefacts and activities interact with classroom design and classroom communication in three school subjects in Swedish secondary school: Home and Consumer Studies, Biology and Chemistry. The research process has been concerned with the affordances that are created through different semiotic resources in classroom design and in classroom communication in the three school subjects, focusing on academic language and student participation. LÄS MER