Sökning: "Vågor"

Visar resultat 16 - 20 av 83 avhandlingar innehållade ordet Vågor.

  1. 16. Transient Electromagnetic Waves in Nonlinear Media

    Författare :Daniel Sjöberg; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Signal processing; nonlinear materials; Electromagnetic waves; instantaneous response; waveguides; shock waves; entropy condition; Elektronik och elektroteknik; Electronics and Electrical technology; Signalbehandling; Electromagnetism; optics; acoustics; Elektromagnetism; optik; akustik;

    Sammanfattning : This thesis is concerned with the propagation of transient electromagnetic waves in nonlinear media. It consists of a General Introduction and five scientific papers. The General Introduction gives a broad overview of nonlinear electromagnetic phenomena. LÄS MER

  3. 17. Integral Identities for Passive Systems and Spherical Waves in Scattering and Antenna Problems

    Författare :Anders Bernland; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dispersion relations; sum rules; physical limitations; Herglotz functions; electromagnetic scattering; antenna theory; spherical wave expansions; antenna measurements; propagation channel measurements;

    Sammanfattning : Sum rules and physical limitations within electromagnetic theory and antenna theory have received significant attention in the last few years. However, the derivations are often relying on application specific and sometimes unsupported assumptions, and therefore a mathematically rigorous and generally applicable approach seems timely. LÄS MER

  4. 18. Rotational effects in water waves

    Författare :Erik Wahlén; Partiella differentialekvationer; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Abstract: This thesis consists of four papers related to various aspects of water waves with vorticity. Paper I: Symmetry of steady periodic gravity water waves with vorticity. LÄS MER

  5. 19. Transient electromagnetic pulse propagation in temporally dispersive materials

    Författare :Igor Egorov; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Green functions; direct scattering; time domain; wave propagation; bi-gyrotropic; chiral; bi-isotropic; Forerunner; precursor; Green dyadics; Electronics and Electrical technology; Elektronik och elektroteknik;

    Sammanfattning : This thesis treats the problem of transient electromagnetic pulse propagation in temporally dispersive media. The analysis is performed using time-domain techniques. In particular, the dispersive wave splitting which decouples the Maxwell equations both in vacuum and inside the medium is utilized. LÄS MER

  7. 20. Inventory of geomechanical phenomena related to train-induced vibrations from tunnels

    Författare :Andreas Eitzenberger; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Geoteknik; Soil Mechanics; Mining and Rock Engineering; Gruv- och berganläggningsteknik;

    Sammanfattning : Banverket is expecting that the number of railway tunnels in densely populated areas will increase over the next 20 years due to the lack of available space on the ground surface, but also since the railway is considered an environmentally friendly solution of transportation for the future. The need for good predictions of vibration and noise levels in dwellings along the planned tunnels is therefore evident. LÄS MER