Search
Feedback
About UniCat 
Help
News
| Listing 1 - 4 of 4 |
Sort by
|
Dissertation
Year: 2022 Publisher: Liège Université de Liège (ULiège)
Abstract | Keywords | Export | Availability | Bookmark
Loading...Choose an application
- Reference Manager
- EndNote
- RefWorks (Direct export to RefWorks)
Underwater Radiated Noise started to be recognized as a threat to the marine ecosystem balance about 50 years ago. Since then, regulations and evaluations of the acoustic signature of big-sized ships have become a common practice. Nowadays, the detection, localization, tracking, and classification of this kind of ship are accurately estimated by radar or AIS. However, in recent years the number of small and mid-sized ships has been increasing rapidly along with human recreational activities in coastal zones, and now is required a better understanding of their environmental impact. Small craft are challenging to detect because of lack of AIS and they have weak acoustic signatures for the most common monitoring systems. Moreover, information published in the literature about the acoustics of this kind of ship is limited, even though they can be widely diverse. This work describes the methodology to design a system to investigate underwater-radiated noise of small craft using only acoustic means. At first, a Direction of Arrival (DOA) model considering two, three and four receivers was formulated and validated. Second, a 4-hydrophones array measurement system was designed, assembled and tested in the bay of Kiel, recording sample data from a motor sailing boat and other vessels passing nearby. Then, the data was processed and evaluated with the DOA model to estimate the bearing location of the recorded sources. Finally, the results were compared with the GPS data from the ships. The system shall then be able to detect the presence of several small craft to later allow entering this information into soundscape calculations.
Book
Abstract | Keywords | Export | Availability | Bookmark
Loading...Choose an application
- Reference Manager
- EndNote
- RefWorks (Direct export to RefWorks)
Noise and vibrations generated by ships affect a wide range of receivers: crew and passengers inside the vessel, inhabitants of the coastal areas and marine fauna outside it. Recent studies suggest that a large percentage of people living in urban areas close to harbors and a number of marine species, at different evolutionary levels (in particular mammals and cephalopods), suffer from ship N&V emissions in air and in water. The present degree of knowledge of the phenomena involved in the noise emissions inside and outside ships is quite different, as a result also of the time elapsed since the negative effects were realized and therefore studied. The development of the normative framework in the various areas reflects these differences, but there are expectations for improvements on all fronts that need to be supported by the scientific community presenting the latest research results in this particular field of acoustics.
Animal Bioacoustics --- harbour noise --- maritime acoustics --- Underwater soundscape --- ship noise --- sonar --- underwater radiated noise --- Propagation loss --- anthropogenic noise --- sound propagation --- Animal Bioacoustics --- harbour noise --- maritime acoustics --- Underwater soundscape --- ship noise --- sonar --- underwater radiated noise --- Propagation loss --- anthropogenic noise --- sound propagation
Book
Abstract | Keywords | Export | Availability | Bookmark
Loading...Choose an application
- Reference Manager
- EndNote
- RefWorks (Direct export to RefWorks)
Noise and vibrations generated by ships affect a wide range of receivers: crew and passengers inside the vessel, inhabitants of the coastal areas and marine fauna outside it. Recent studies suggest that a large percentage of people living in urban areas close to harbors and a number of marine species, at different evolutionary levels (in particular mammals and cephalopods), suffer from ship N&V emissions in air and in water. The present degree of knowledge of the phenomena involved in the noise emissions inside and outside ships is quite different, as a result also of the time elapsed since the negative effects were realized and therefore studied. The development of the normative framework in the various areas reflects these differences, but there are expectations for improvements on all fronts that need to be supported by the scientific community presenting the latest research results in this particular field of acoustics.
Animal Bioacoustics --- harbour noise --- maritime acoustics --- Underwater soundscape --- ship noise --- sonar --- underwater radiated noise --- Propagation loss --- anthropogenic noise --- sound propagation
Book
Abstract | Keywords | Export | Availability | Bookmark
Loading...Choose an application
- Reference Manager
- EndNote
- RefWorks (Direct export to RefWorks)
Noise and vibrations generated by ships affect a wide range of receivers: crew and passengers inside the vessel, inhabitants of the coastal areas and marine fauna outside it. Recent studies suggest that a large percentage of people living in urban areas close to harbors and a number of marine species, at different evolutionary levels (in particular mammals and cephalopods), suffer from ship N&V emissions in air and in water. The present degree of knowledge of the phenomena involved in the noise emissions inside and outside ships is quite different, as a result also of the time elapsed since the negative effects were realized and therefore studied. The development of the normative framework in the various areas reflects these differences, but there are expectations for improvements on all fronts that need to be supported by the scientific community presenting the latest research results in this particular field of acoustics.
Animal Bioacoustics --- harbour noise --- maritime acoustics --- Underwater soundscape --- ship noise --- sonar --- underwater radiated noise --- Propagation loss --- anthropogenic noise --- sound propagation
| Listing 1 - 4 of 4 |
Sort by
|