Sökning: "Dispersion"

Visar resultat 1 - 5 av 747 avhandlingar innehållade ordet Dispersion.

  1. 1. Dispersion Engineering Negative Refraction and Designed Surface Plasmons in Periodic Structures

    Detta är en avhandling från Stockholm : KTH

    Författare :Zhichao Ruan; Min Qiu; Henri Benisty; [2007]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; photonic crystal; dispersion property; negative refraction; surface plasmon polariton; designed surface plasmon; negative index material; layer-KKR method; finite-difference time-domain method; plane wave method; subwavelength imaging; open cavity; enhanced transmission; slowing light; TECHNOLOGY Electrical engineering; electronics and photonics Photonics; TEKNIKVETENSKAP Elektroteknik; elektronik och fotonik Fotonik;

    Sammanfattning : The dispersion property of periodic structures is a hot research topic in the last decade. By exploiting dispersion properties, one can manipulate the propagation of electromagnetic waves, and produce effects that do not exist in conventional materials. LÄS MER

  2. 2. Theoretical Investigation into Longitudinal Dispersion in Natural Rivers — A Scaling Dispersion Model

    Detta är en avhandling från Department of Water Resources Engineering, Lund Institute of Technology, Lund University

    Författare :Zhi-Qiang Deng; [2002]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; soil mechanics; Väg- och vattenbyggnadsteknik; Environmental technology; pollution control; Miljöteknik; kontroll av utsläpp; offshore technology; hydraulic engineering; Civil engineering; Scaling dispersion.; Parameter estimation; Numerical scheme; Dispersion coefficient; Natural river;

    Sammanfattning : Using a broad variety of scientific methods this dissertation systematically investigates the fundamental mechanisms underlying the dispersion processes in natural rivers and their mathematical descriptions in a geometrical framework. Emphasis is on the geometrical variations and irregularities of a natural river and their scales. LÄS MER

  3. 3. InP-based photonic crystals Processing, Material properties and Dispersion effects

    Detta är en avhandling från Stockholm : KTH

    Författare :Audrey Berrier; Srinivasan Anand; Alfred Forchel; [2008]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Photonic crystals; indium phosphide; photonic bandgap; Bloch modes; slow light; dispersion; coupled cavity waveguides; chemically assisted ion beam etching; lag effect; cavities; optical losses; carrier transport; carrier lifetimes; negative refraction; photonic bandstructure; NATURAL SCIENCES Physics; NATURVETENSKAP Fysik;

    Sammanfattning : Photonic crystals (PhCs) are periodic dielectric structures that exhibit a photonic bandgap, i.e., a range of wavelength for which light propagation is forbidden. The special band structure related dispersion properties offer a realm of novel functionalities and interesting physical phenomena. LÄS MER

  4. 4. First-principles calculations of long-range intermolecular dispersion forces

    Detta är en avhandling från Institutionen för fysik, kemi och biologi

    Författare :Auayporn Jiemchooroj; Bo E. Sernelius; Irina Yakimenko; [2006]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; van der Waals forces; dispersion forces; intermolecular interactions; dispersion coefficients; polarizability; NATURAL SCIENCES Physics; NATURVETENSKAP Fysik;

    Sammanfattning : This work presents first-principles calculations of long-range intermolecular dispersion energies between two atoms or molecules as expressed in terms of the C6 dipole-dipole dispersion coefficients. In a series of publications, it has been shown by us that the complex linear polarization propagator method provides accurate ab initio and first-principles density functional theory values of the C6 dispersion coefficients in comparison with those reported in the literature. LÄS MER

  5. 5. Dispersion modelling of volcanic emissions

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Adam Dingwell; Rutgersson Anna; David Simpson; [2016]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; dispersion modelling; atmospheric; volcano; gas emissions; volcanic ash; FLEXPART; FLEXPART-WRF; Spridningsmodellering; atmosfär; vulkan; gasutsläpp; vulkanaska; FLEXPART; FLEXPART-WRF; Meteorology; Meteorologi;

    Sammanfattning : Gases and particles released by volcanoes pose a serious hazard to humans and society. Emissions can be transported over long distances before being reduced to harmless concentrations. Knowing which areas are, or will be, exposed to volcanic emissions is an important part inreducing the impact on human health and society. LÄS MER