Sökning: "nonuniform fields"

Hittade 3 avhandlingar innehållade orden nonuniform fields.

  1. 1. Multipactor in low pressure gas and in nonuniform rf field structures

    Författare :Richard Udiljak; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; detection methods; iris; low pressure gas; coax; nonuniform fields; Multipactor; microwave discharge; breakdown; discharge;

    Sammanfattning : Resonant electron multiplication in vacuum, multipactor, is analysed for several geometries where the RF electric field is nonuniform. In particular, it is shown that the multipactor behaviour in a coaxial line is both qualitatively and quantitatively different from that observed with the conventionally used simple parallel-plate model. LÄS MER

  3. 2. Generation of magnetic fields in plasmas

    Författare :Nitin Shukla; Gert Brodin; Dusan Jovanovic; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Relativistic and non-relativistic plasma outflows are quite ubiquitous in astrophysical scenarios, as well as in laboratory plasmas. The propagation of relativistic and non- relativistic charged particle beams in background plasmas provides return currents in the opposite direction and interactions between the currents then drive several plasma instabilities involving the longitudinal (electrostatic instabilities) and trans- verse (electromagnetic instability) modes. LÄS MER

  4. 3. Moisture Induced Stresses in Timber Structures

    Författare :Johan Jönsson; Avdelningen för Konstruktionsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Teknik; load carrying capacity; Technological sciences; reinforcement; short-term strength perpendicular to grain; internal stresses; glulam; contact free measuring technique moisture gradients;

    Sammanfattning : Wood is a hygroscopic material; always striving to reach equilibrium with the surrounding air, and consequently the moisture content is different in different climate conditions. The strength of wood is directly dependent on the moisture content, lower moisture content leads to increasing strength. LÄS MER