Sökning: "noise 2010"

Visar resultat 1 - 5 av 68 avhandlingar innehållade orden noise 2010.

  1. 1. On measurement and monitoring of reactivity in subcritical reactor systems

    Författare :Carl Berglöf; Janne Wallenius; Vasily Arzhanov; Massimo Salvatores; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; reactor; ADS; accelerator-driven systems; subcriticality determination; noise techniques; pulsed neutron source; reactivity monitoring; Nuclear physics; Kärnfysik;

    Sammanfattning : Accelerator-driven systems have been proposed for incineration of transuranic elements from spent nuclear fuel. For safe operation of such facilities, a robust method for reactivity monitoring is required. Experience has shown that the performance of reactivity measurement methods in terms of accuracy and applicability is highly system dependent. LÄS MER

  3. 2. Large Eddy Simulation for the Analysis of Supersonic Jet Noise Suppression Devices

    Författare :Markus Olander Burak; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluidic injection; mixer-ejector; jet noise; Kirchhoff; forward flight effects; LES; acoustic liner; supersonic turbulent jets; broadband time-domain impedance boundary condition; chevrons; shock-associated noise; CAA; aeroacoustics;

    Sammanfattning : Stricter noise regulations for commercial and military aircraft have increased interest in noise reduction techniques within the aerospace industry. To meet the requirements, new noise suppression technologies have to be developed and numerical methods need to be validated and possibly improved for the correct assessment of these technologies. LÄS MER

  4. 3. Applicable directivity description of railway noise sources

    Författare :Xuetao Zhang; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; directivity; the Doppler factor; scattered fluid sound; railway noise; perpendicular dipole pair;

    Sammanfattning : For a sound source, directivity is an important parameter to specify. This parameter also reflects the physical feature of the sound generation mechanism. For example, turbulence sound is of quadrupole directivity whilst fluid-structure interaction often induces a sound of dipole characteristic. LÄS MER

  5. 4. InAs/AlSb HEMTs for Cryogenic Low-Noise Applications

    Författare :Giuseppe Moschetti; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cryogenic; metamorphic; high frequency; high electron mobility transistor HEMT ; low power; low noise.; InAs AlSb;

    Sammanfattning : The InAs/AlSb high electron mobility transistor (HEMT) is an emerging microwave device technology. The high electron mobility and high peak electron velocity of the InAs channel makes this device technology a potential candidate for low-noise applications operating at very low power dissipation. LÄS MER

  7. 5. Traffic noise and cardiovascular disease

    Författare :Jenny Selander; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :;

    Sammanfattning : Traffic noise is an increasing problem in urban areas worldwide, but health effects in relation to traffic noise exposure are not well understood. Several studies show that noise may give rise to acute stress reactions, possibly leading to cardiovascular effects, but the evidence is limited on cardiovascular risks associated with traffic noise exposure. LÄS MER