Sökning: "urban sound propagation"
Visar resultat 1 - 5 av 6 avhandlingar innehållade orden urban sound propagation.
1. Sound propagation from sustainable ground vehicles : from aeroacoustic sources to urban noise
Sammanfattning : Transportation is the main source of environmental noise in Europe, with an estimated 125 million people affected by excessive noise levels from road traffic, causing a burden of noise related diseases and having a substantial economic impact on society. In order to reduce exposure to high levels of traffic noise, two approaches are the topic of extensive research: preventing sound from propagating from roads and railways using for example noise barriers, and reducing the sources of noise themselves. LÄS MER
2. Predicting the sound field from aeroacoustic sources on moving vehicles : Towards an improved urban environment
Sammanfattning : In a society where environmental noise is becoming a major health and economical concern, sound emissions are an increasingly critical design factor for vehicle manufacturers. With about a quarter of the European population living close to roads with heavy traffic, traffic noise in urban landscapes has to be addressed first. LÄS MER
3. Numerical modelling of sound propagation to closed urban courtyards
Sammanfattning : Because modern urban environments suffer from excessive levels of road traffic noise, access to closed courtyards is essential in order to offer urban sound environments of high quality with regard to health and perceived sound. To reach this quality, which is described by the quiet side definition, the 24-hour equivalent noise level should be below 45 dB(A). LÄS MER
4. Auralisation of airplanes considering sound propagation in a turbulent atmosphere
Sammanfattning : Aircraft noise is a major issue in urban areas. Due to a rising level ofurbanisation and the continuing growth of air traffic more people are exposed toaircraft noise than ever. Methods currently used for assessing theimpact of aircraft noise on humans consider mostly energetic quantities, and not thedynamic character of the sound. LÄS MER
5. Sound propagation to two-dimensional shielded urban areas: a numerical and scale model study of façade treatments
Sammanfattning : .... LÄS MER