Sökning: "sound attenuation"

Visar resultat 1 - 5 av 29 avhandlingar innehållade orden sound attenuation.

  1. 1. Structural sound transmission and attenuation in lightweight structures

    Författare :Lars-Göran Sjökvist; RISE; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sound insulation; acoustics; wooden houses; Fourier transform; lightweight building; stiffened plate; junction; stiffeners; flanking transmission; attenuation;

    Sammanfattning : Everyone wants a peaceful and quiet home, but in noisy cities it is a challenge to create such homes. New building techniques are mostly introduced for other purposes than noise control -- stability, economy, heat transfer and so on. LÄS MER

  3. 2. Absorption of Sound : On the effects of field interaction on absorber performance

    Författare :Anna Färm; Mats Åbom; Ragnar Glav; Susann Boij; Gareth Bennett; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Sound absorption; Porous absorbers; Bulk reaction; Local reaction; Boundary layer; Grazing flow; Temperature gradients; Surface impedance; Sound field; Pass-by noise; Vehicle and Maritime Engineering; Farkostteknik;

    Sammanfattning : Environmental noise has for decades been a well known problem, especially in urban areas. As noise requirements for vehicles are sharpened, noise reducing concepts are needed in early design stages requiring accurate simulations to support the design. LÄS MER

  4. 3. Sound attenuation in railway track

    Författare :Robert Hildebrand; KTH; []
    Nyckelord :;

    Sammanfattning : .... LÄS MER

  5. 4. Acoustical properties of earplugs

    Författare :Per Hiselius; Teknisk akustik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; vibration and acoustic engineering; vacuum technology; hydraulics; Mechanical engineering; acoustic modelling; objective measurement; insertion loss; earplugs; HPE; HPD; hearing protectors; Two-Port; Four-Pole; attenuation; electro acoustics; acoustics;

    Sammanfattning : In this study an experimental setup for measurements of high impedance objects in ducts, yielding the acoustical Two-Port properties of the object, is applied to earplugs. A frequently used experimental setup for measuring objective acoustical properties of earplugs is that of artificial ears. Great effort is spent on duplicating the human ear. LÄS MER

  7. 5. Determining the quality of natural gas and biomethane : Development of a correlative method and instrument prototype for measuring gas quality

    Författare :Taras Koturbash; Vladimir G. Kutcherov; Andrew R. Martin; Khaled Loubar; KTH; []
    Nyckelord :Natural gas; biomethane; calorific value; Wobbe Index; ultrasonic measurement; sound attenuation; Energy Technology; Energiteknik;

    Sammanfattning : The composition of natural gas highly depends on its origin: natural gas from various deposits, substitute natural gas that can be produced from fossil fuels or renewable sources. The intermixing of gases from various supply sources during pipeline transportation also leads to more complicated and unpredictable gas composition variations at the consumption site. LÄS MER