Sökning: "acoustics"

Visar resultat 21 - 25 av 1039 avhandlingar innehållade ordet acoustics.

  1. 21. Vibration of sandwich beams

    Författare :Daniel Backström; Anders Nilsson; Goran Pavic; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustics; Akustik;

    Sammanfattning : Some aspects and properties of the lateral vibration of sandwich beams are investigated, including the concept of apparent bending stiffness and shear modulus, allowing the sandwich beam dynamics to be approximately described by classical beam theory. A sixth order beam model is derived including boundary conditions, and the free and forced response of some beam configurations analyzed. LÄS MER

  3. 22. Magneto-sensitive rubber in the audible frequency range

    Författare :Peter Blom; Leif Kari; Luigi Bregant; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Magneto-sensitivity; Rubber; Audible frequency range; Amplitude dependence; Vibration isolator; Fletcher-Gent effect; Stiffness; Acoustics; Akustik;

    Sammanfattning : The dynamic behaviour in the audible frequency range of magneto-sensitive (MS) rubber is the focus of this thesis consisting of five papers A-E. Paper A presents results drawn from experiments on samples subjected to different constant shear strains over varying frequencies and magnetic fields. LÄS MER

  4. 23. Masking of wind turbine sound by ambient noise

    Författare :Karl Bolin; Mats Åbom; Sten Ljunggren; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustics; Akustik;

    Sammanfattning : The main objective of this work was to gain an increasing understanding of the properties of vegetation noise and also to the relative ratios of different natural ambient noises to mask wind turbine sound. A discrete vegetation noise model was developed and compared to an earlier model showing improved estimations, especially at frequencies below 0. LÄS MER

  5. 24. Wind Turbine Noise and Natural Sounds : Masking, Propagation and Modeling

    Författare :Karl Bolin; Mats Åbom; Jens Forssén; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wind turbine noise; models of natural sound sources; masking; Acoustics; Akustik;

    Sammanfattning : Wind turbines are an environmentally friendly and sustainable power source. Unfortunately, the noise impact can cause deteriorated living conditions for nearby residents. The audibility of wind turbine sound is influenced by ambient sound. This thesis deals with some aspects of noise from wind turbines. LÄS MER

  7. 25. Structural-acoustic analysis of wall-to-floor joints in timber-framed housing

    Författare :Åsa Bolmsvik; Torbjörn Ekevid; Göran Sandberg; Växjö universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustics; Akustik; Building engineering; Byggnadsteknik; Byggteknik; Civil engineering;

    Sammanfattning : Even though a building meets the regulations with respect to impact sound, structures with wooden frames may receive complaints from the inhabitants due to structure-borne sound in the lower frequencies. In this thesis measuring methods that are more precise than the traditional measuring methods have been used to see if they could give a better knowledge about flanking transmission in the low frequencies in timber-framed structures. LÄS MER