Sökning: "airborne noise"

Visar resultat 1 - 5 av 24 avhandlingar innehållade orden airborne noise.

1. 1. INDOOR NOISE FROM URBAN RAILBOUND TRANSPORT

   Författare :SIGMUND OLAFSEN; Teknisk akustik; []
   Nyckelord :Tramway noise; acoustics; Indoor noise;

   Sammanfattning : Methods for determination of indoor noise and vibrations from urban rail bound transport are presented in this work. Both measurement methods and empirical prediction methods are described. The data and results are taken from field measurements of noise and vibrations from the trams and metro trains of Oslo. LÄS MER

3. 2. Acoustic excitation and transmission of lightweight structures

   Författare :Jonas Brunskog; Teknisk akustik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; point mobility; Lamb waves; wood.; Building construction; plate excitation; cavities; near-periodicity; nearly periodic; sound insulation; timber; structural acoustics; spatial Fourier transform; resilient device; prediction model; periodic; lightweight; ISO tapping machine; airborne noise; Building acoustics; impact noise; Byggnadsteknik;

   Sammanfattning : In order to increase our knowledge of the sound transmission and radiation processes of lightweight wall and floor structures, theoretical models are needed. Detailed models may form a valuable tool. In lightweight floor structures, impact sound insulation is perhaps the most important property to consider. LÄS MER

4. 3. Orphan source detection in mobile gamma-ray spectrometry - Improved techniques for background assessment

   Författare :Peder Kock; Malmö Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Gamma spectrometry; airborne; car-borne; radioactive; orphan sources; hypothesis testing; background radiation;

   Sammanfattning : Hazardous radioactive sources out of regulatory control are referred to as orphan sources. Focussing on gamma-emitting orphan sources, this thesis describes methods that can be used in mobile gamma-ray spectrometry to perform real-time discrimination between an actual source signal and the signal due to the natural radiation background. LÄS MER

5. 4. Acoustical Characteristics of Aircraft Panels

   Författare :Bilong Liu; Leping Feng; Jie Pan; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustics; sound transmission loss; stiffener; stiffening; aircraft panel; cylindrical shell; turbulent boundary layer; TBL; noise; sound radiation; Acoustics; Akustik;

   Sammanfattning : A deterministic approach based on a modal expansion and modal receptance method has been developed to evaluate the airborne sound insulation of aircraft panels with stringer and ring frame attachments. Furthermore, this method was extended to predict the noise radiation of stiffening panel subjected to TBL excitation. LÄS MER

7. 5. Airborne sound insulation of single and double plate constructions

   Författare :Ulrica Kernen; Gudni Jóhannesson; Waldemar Maysenhölder; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Construction engineering; : Airborne sound insulation; single plate; double plate; floating-floor; sound reduction index; sound transmission.; Byggnadsteknik; Building engineering; Byggnadsteknik;

   Sammanfattning : The sound insulation demands for dwellings and public building has increased over the years as the number of sound sources has grown. From the outside our homes are exposed to noise from cars, trains, airplanes, etc. Noise intrudes from our neighbours and their television and stereo equipments. LÄS MER