Sökning: "random media"

Visar resultat 6 - 10 av 37 avhandlingar innehållade orden random media.

  1. 6. The Influence of Atmospheric Turbulence on Barrier Sound Reduction

    Författare :Jens Forssén; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; traffic noise; barrier; measurements; turbulence; scattering cross-section; substitute sources; outdoor sound propagation; parabolic equation method; random media; numerical modelling;

    Sammanfattning : Numerical modelling and measurements are used for studying the reduced performance of a noise barrier, caused by a turbulent atmosphere. The turbulence scatters the sound, which leads to an increased noise level in the acoustic shadow region behind the barrier. LÄS MER

  3. 7. Characterization and Design Requirements for Antennas in the Near-field and the Random-LOS Propagation Environment

    Författare :Aidin Razavi; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polarization-MIMO; Random-LOS; OTA; Antenna measurements; near-field antennas; antenna characterization; MIMO; near-field focusing;

    Sammanfattning : The choice of antenna for a particular application depends on the requirements imposed by that application. These can be, the application's field region (i.e., near-field or far-field), polarization, radiation pattern, radiation efficiency, system throughput, etc. LÄS MER

  4. 8. Distributed Optimization of P2P Media Delivery Overlays

    Författare :Amir H. Payberah; Seif Haridi; Alberto Montresor; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; P2P overlay networks; P2P live streaming; Distributed optimization; Electronics; Elektronik; Computer and systems science; Data- och systemvetenskap;

    Sammanfattning : Media streaming over the Internet is becoming increasingly popular. Currently, most media is delivered using global content-delivery networks, providing a scalable and robust client-server model. However, content delivery infrastructures are expensive. LÄS MER

  5. 9. Activity recognition in resource-constrained pervasive systems

    Författare :Niklas Karvonen; Chris Nugent; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Pervasive Mobile Computing; Distribuerade datorsystem;

    Sammanfattning : There is an increasing need for personalised and context-aware services in our everyday lives and we rely on mobile and wearable devices to provide such services. Data collected from these devices includes important information about users’ movements, locations, physiological status, and environment. LÄS MER

  7. 10. Scattering of seismic waves in random velocity models : Finite difference simulation

    Författare :Lena Frenje; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; Geovetenskap; Earth sciences; Geovetenskap; Geofysik med inriktning mot fasta jordens fysik; Geophysics with specialization in Solid Earth Physics;

    Sammanfattning : The small-scale heterogeneities within the Earth's crust and the effect these heterogeneities have on seismic waves have gained increasing interest in the last 15 years. One approach to study seismic wave scattering is through numerical simulations in random media. LÄS MER