Search for dissertations about: "akustik"

Showing result 1 - 5 of 844 swedish dissertations containing the word akustik.

  1. 1. Numerical Modelling of Dynamics of Light Porous Materials

    University dissertation from Peter Göransson, FFA, PO Box 11021, SE-161 11 Bromma, Sweden

    Author : Peter Göransson; Lund University.; Lunds universitet.; [1998]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mechanical engineering; glass fibre; foam; material characterisation; elasto-acoustic; fluid-structure interaction; finite element; Biot; porous material; hydraulics; vacuum technology; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik;

    Abstract : Porous materials are among the most commonly used materials for noise and vibration reduction in modern transportation vehicles. To design, industrially relevant, weight and cost effective noise and vibration measures, there is a need for general prediction models capable of representing the elasto-acoustic behaviour of such materials. READ MORE

  2. 2. Acoustical properties of earplugs

    University dissertation from Engineering Acoustics, LTH, Lund University

    Author : Per Hiselius; Lund University.; Lunds universitet.; [2005]
    Keywords : 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;

    Abstract : 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. READ MORE

  3. 3. Drum sound from floor coverings - objective and subjective assessment

    University dissertation from Engineering Acoustics, LTH, Lund University

    Author : Ann-Charlotte Johansson; Lund University.; Lunds universitet.; [2005]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vakuumteknik; vibrationer; akustik; hydraulik; Maskinteknik; vacuum technology; vibration and acoustic engineering; hydraulics; acoustic standard; Mechanical engineering; tapping machine; veneer flooring; parquet flooring; binaural recording; foot impact; loudness; sound quality; listening test; paired comparisons; walking sound; drum sound; building acoustics; psychoacoustics; laminate flooring;

    Abstract : Drum sound is the sound produced when an object, such as a foot, hits the flooring in the room in which the receiving ear is located. Drum sound has attracted interest in recent years, particularly due to an increased use of thin floating floor constructions, such as veneer or laminate flooring, which can produce loud and sharp walking sound. READ MORE

  4. 4. A Novel Signal Model and Estimation Method for Acoustic Doppler Current Meters

    University dissertation from Technical Acoustics, LTH, Box 118, 221 00 LUND

    Author : Thomas L Lagö; Lund University.; Lunds universitet.; [1999]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Doppler Profiler; Acoustic Doppler; Gaussian Backscattering Model; ADCM; ADCP; The Symmiktos Method; Estimation; Doppler; Current; MPCA.; Technological sciences; Teknik; Electromagnetism; optics; acoustics; Elektromagnetism; optik; akustik;

    Abstract : This thesis deals with the process of estimating underwater current from the backscattering signal transmitted from an ultrasonic transducer. The narrowband sinusoidal burst signal is Doppler-shifted due to the current, and this information is converted into current. READ MORE

  5. 5. Applications of the Complex Modulation Transfer Function on SEA-systems

    University dissertation from Dept. of Engineering Acoustics, LTH, Lund University, P.O.B. 118 SE-221 00 Lund Sweden

    Author : Karl-Ola Lundberg; Lund University.; Lunds universitet.; [1999]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vacuum technology; hydraulics; Mechanical engineering; modulated noise; in-situ; modulation transfer function; loss factor; SEA; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik;

    Abstract : The SEA coupling and dissipation loss factors are determined in-situ from Complex Modulation Transfer Functions, CMTF:s, based on measured impulse-responses. A quotient of CMTF:s is least-square curve-fitted to a SEA model and the SEA loss factors are determined from the results of the curve-fit. READ MORE