Thesis (Ph.D.) - University of Birmingham, Dept of Electrical and Electronic Engineering, 1988.
|Statement||by Nicholas Flowers.|
Greenwood, B., Richards, R.G. and Brander, R.W., Acoustic imaging of sea-bed geometry: A High Resolution Remote Tracking Sonar (HRRTS II). Mar. Geol., A High Resolution Remote Tracking Sonar (HRRTS II) is described which is capable of measuring a 2-D profile of the sea-bed over a maximum distance of 5 m under conditions of. Introduction. Acoustic backscatter (ABS) measurement is a non-intrusive technique for the monitoring of suspended sediment particles in the water column and changing seabed characteristics (see Figures 1 and 2). An acoustic backscatter instrumentation package comprises acoustic sensors, data acquisition, storage and control electronics, and data extraction and reduction software. Acoustic seabed classification has been carried out in the Baltic Sea using multi-or singlebeam acoustic methods evaluating mainly processed backscattered signals (e.g. Tęgowski ; Orlowski Author: Jarosław Tęgowski. Underwater Acoustic Imaging of the Sea Article (PDF Available) in Archives of Acoustics 39(4) December with 1, Reads How we measure 'reads'.
A drop video camera was also used to provide groundtruthing for the acoustic results at selected stations. A RoxAnn-like technique was adopted for acoustic classification of the seabed habitat types. An analysis of the backscattered signals was also made to determine the . The reassigned spectrogram and the tree other time–frequency techniques are applied to an experimental acoustic signals backscattered by an aluminum tube with radius ratio b / a = (b: internal radius and a: external radius), immersed in water. The synthetic images obtained present the circumferential wave trajectories (S0, A1 and S1) and Cited by: 7. The normal excitation of a tube immersed in water by the acoustic plane wave permits the generation of circumferential waves inside the shell and around the shell-water interface. These circumferential waves form standing waves on the circumference of the tube for some frequencies. Moreover, the studies carried out on the diffusion of a plane acoustic wave by target were based primarily on the Author: Mustapha Laaboubi, Elhoucien Aassif, Rachid Latif, Gerard Maze, Dominique Decultot, Ali Moudden, Abd. Backscattered acoustic signals from annealed polycrystalline aluminium are observed to possess fractal characteristics. Assuming this to be true a gra Cited by: 2.
Acoustic seabed classification is the partitioning of a seabed acoustic image into discrete physical entities or classes. This is a particularly active area of development in the field of seabed mapping, marine geophysics, underwater acoustics and benthic habitat classification is one route to characterizing the seabed and its habitats. Abstract. To investigate the hydrodynamic activity of the seabed in the German Bight, underwater remote sensing was carried out over an area of 32 km 2 located 20 km northeast of Helgoland island in the southern North Sea in January, May and August On the basis of acoustic seabed classification, six seabed types have been identified by the combined evaluation of side-scan Cited by: Background. Underwater acoustic instruments has been an indispensable tool to study the ocean. Echo sounder is one of the acoustic instrument used to remotely classify distributions of biological organisms such as fish and plankton (MacLennan and Simmonds, ; Furusawa, ).Knowledge of species, location, and behavior observed by the sounders are important for fisheries, fisheries Cited by: 6. The issue of whether remote acoustic seabed classification is a useful and cost-effective means to map seabed type for purposes of charting is a question each HO must address. It must do so within the context of its survey capability, its need for continuous seabed mapping and the very real cost in time and physical resources.