Sökning: "strong coupling constant"

Visar resultat 6 - 10 av 22 avhandlingar innehållade orden strong coupling constant.

  1. 6. Electromechanics of Vertical Axis Wind Turbines

    Författare :Morgan Rossander; Sandra Eriksson; Hans Bernhoff; Daniel Karlsson; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wind power; Diode rectification; Control; Measurement; Simulation; Electromechanical coupling; vindkraft; diodlikriktning; reglering; mätning; simulering; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Sammanfattning : Wind power is an established mean of clean energy production and the modern horizontal axis wind turbine has become a common sight. The need for maintenance is high and future wind turbines may need to be improved to enable more remote and offshore locations. LÄS MER

  3. 7. Measurement of azimuthal asymmetries in the hadronic final-state of deep inelastic scattering at HERA

    Författare :Magnus Lindström; Partikel- och kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; jets; DIS; azimuthal asymmetries; structure function; unfold; quantum field theory; Elementary particle physics; Elementarpartikelfysik; kvantfältteori; Physics; Fysik; Fysicumarkivet A:2000:Lindström;

    Sammanfattning : Azimuthal asymmetries of the hadronic final state in deep inelastic scattering at HERA provide the opportunity to study the helicity of the interacting particles. We present a theoretical overview of the origin of these effects up to leading order in the strong coupling constant, $alpha_s$. LÄS MER

  4. 8. Extremal eigenvalues and geometry of quantum graphs

    Författare :Andrea Serio; Pavel Kurasov; Annemarie Luger; Evans Harrell; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quantum graphs; spectral estimates; trace formula; Euler characteristic; Mathematics; matematik;

    Sammanfattning : This thesis consists of four papers concerning topics in the spectral theory of quantum graphs, which are differential operators on metric graphs.In paper I we present a family of graphs with an arbitrary number of cycles for which a certain eigenvalue upper estimate is sharp. LÄS MER

  5. 9. Cases of coupled vibrations and prametric instability in rotating machines

    Författare :Jean-Claude Luneno; Ilmar Santos; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : The principal task in this research project was to analyse the causes and consequences of coupled vibrations and parametric instability in hydropower rotors; where both horizontal and vertical machines are involved. Vibration is a well-known undesirable behavior of dynamical systems characterised by persistent periodic, quasi-periodic or chaotic motions. LÄS MER

  7. 10. Optical Studies of Periodic Microstructures in Polar Materials

    Författare :Herman Högström; Carl Gustaf Ribbing; Clivia M. Sotomayor Torres; Uppsala universitet; []
    Nyckelord :Engineering physics; polaritonic; polar; photonic crystal; surface phonon polariton; multilayer; Reststrahlen; SiC; SiO2; Teknisk fysik;

    Sammanfattning : The optical properties of matter are determined by the coupling of the incident electromagnetic radiation to oscillators within the material. The oscillators can be electrons, ions or molecules. Close to a resonance the dielectric function exhibits strong dispersion and may be negative. LÄS MER