Sökning: "scattering measurement"

Visar resultat 16 - 20 av 142 avhandlingar innehållade orden scattering measurement.

  1. 16. 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

  3. 17. Laser spectroscopic analysis of atmospheric gases in scattering media

    Författare :Mikael Sjöholm; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fjärranalys; Remote sensing; Laser spectroscop; Scattering of light; Diode lasers; acoustics; optics; Electromagnetism; optik; akustik; Elektromagnetism; Optical absorption; Nondestructive testing: optical; Interdisciplinary applications of physics; Laser technology; Atom- och molekylärfysik; Atomic and molecular physics; LIDAR remote sensing; Laserteknik;

    Sammanfattning : Laser spectroscopic techniques for gas analysis under various influences of light scattering are explored in a wide spectral range from the ultraviolet to the infrared. The techniques rely on spectrally narrow-band light sources that are used in differential optical absorption measurements. LÄS MER

  4. 18. Direct and Inverse Methods for Waveguides and Scattering Problems in the Time Domain

    Författare :Erik Abenius; Per Lötstedt; Mats Gustafsson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Maxwell s equations; time-domain; FDTD; finite-element; hybrid; thin sheet; waveguide; PML; inverse scattering; adjoint; gradient-based; minimization; Beräkningsvetenskap med inriktning mot numerisk analys; Scientific Computing with specialization in Numerical Analysis;

    Sammanfattning : Numerical simulation is an important tool in understanding the electromagnetic field and how it interacts with the environment. Different topics for time-domain finite-difference (FDTD) and finite-element (FETD) methods for Maxwell's equations are treated in this thesis. LÄS MER

  5. 19. Whiteness and Fluorescence in Layered Paper and Board : Perception and Optical Modelling

    Författare :Ludovic Gustafsson Coppel; Per Edström; Caisa Johansson; Markku Hauta-Kasari; Mittuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Whiteness; Perception; Colour Appearance Modelling; Paper Optics; Light Scattering; Fluorescence; Lateral Light Scattering; White-Top Mottle; Kubelka-Munk; Radiative Transfer;

    Sammanfattning : This thesis is about modelling and predicting the perceived whiteness of plain paper from the paper composition, including fluorescent whitening agents. This involves psychophysical modelling of perceived whiteness from measurable light reflectance properties, and physical modelling of light scattering and fluorescence from the paper composition. LÄS MER

  7. 20. Laser Remote Sensing for Environmental Monitoring

    Författare :Zuguang Guan; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fiber-optic sensor; gas analysis; food-package monitoring; multiple scattering; zero-background measurement; diode laser spectroscopy; ecological study; aerosol; trace pollutant; LIDAR; laser-induced fluorescence; DIAL; methane monitoring;

    Sammanfattning : This thesis studies the techniques of laser remote sensing and their applications in environmental monitoring, as documented in several published papers. The environment where the human being live is degrading with an accelerating speed. LÄS MER