Sökning: "Dielectric Functions"

Visar resultat 21 - 25 av 29 avhandlingar innehållade orden Dielectric Functions.

  1. 21. Van der Waals and Casimir interactions near metal films

    Författare :Mathias Boström; G. D. Mahan; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis deals with van der Waals and Casimir forces near metal films. Thick, thin and strictly two-dimensional metal films will be investigated. For many applications one can model a double quantum-well structure with two strictly two-dimensional metallic sheets. LÄS MER

  3. 22. Photo diodes for machine vision : device characteristics and a-Si:H deposition and analysis

    Författare :Annika Rantzer; Marcus Böhm; Linköpings universitet; []
    Nyckelord :TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : During the last years the area of digital cameras based on CMOS technology has grown rapidly. In CMOS, signal processing circuitry and sensor elements can be combined on the same chip, which has resulted in advanced machine vision chip designs. LÄS MER

  4. 23. Structural characterization of complex inorganic materials using solid-state NMR spectroscopy

    Författare :Hua Guo; Ulrich Häusserman; Sven Lidin; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; solid-state NMR; materials characterization; inorganic materials; Calcium phosphate cements; bone-substitution materials; Mixed-anion compounds; perovskite; Oxyhydride materials; Oxynitride materials; Barium titanate; Strontium vanadate; oorganisk kemi; Inorganic Chemistry;

    Sammanfattning : Over the past decades, advancements in technology have relied greatly on the development of new functional inorganic materials. Detailed structural characterization of these materials is key for the understanding and also prediction of chemical and physical properties. LÄS MER

  5. 24. Miniaturized Hard Waveguides in Multifunction Array Antennas

    Författare :Malcolm Ng Mou Kehn; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; interlaced arrays; Floquet theorem; reflector antennas; focal plane array; multifunction antennas; miniaturized waveguides; multilayer structures; spectral domain technique; periodic structures; aperture reuse; method of moments; soft and hard surfaces; array antennas;

    Sammanfattning : Recent advances in technologies of wireless communications systems have led to an increasing desire for several antennas performing diverse functions at different frequencies to be integrated into a common radiating aperture. This gives rise to the so-called multifunction antenna, which affords the saving of scarce premium real estate and can alleviate problems arising from excessive antenna protrusions in aspects such as aerodynamics, aesthetics, and stealth capability in military applications. LÄS MER

  7. 25. Moment Method Analysis of Antennas on Cylindrical Structures by Using G2DMULT and Design of Hat Fed Reflector Antennas

    Författare :Jian Yang; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; G2DMULT; reflector antenna; paraboloid; dipole; base station antenna; screw heads; vertex plate; self impedance; G1DMULT; ring-shaped phase center; radiation efficiency; FDTD; cylindrical structures; V2D; ring-focus; moment method;

    Sammanfattning : This thesis deals with two aspects of research interest: moment method analysis of antennas on cylindrical structures by using G2DMULT, and design of hat fed reflector antennas. Both of them are two-dimensional (2D) structure problems, one being cylindrical and the other rotationally symmetric. LÄS MER