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Van Walree, P.A. (author), Ainslie, M.A. (author), Simons, D.G. (author)Echo energies of single-beam echo sounders are inverted for the sediment mean grain size via a combination of theoretical and empirical relationships. In situ measurements of the seafloor mass density have revealed the presence of a thin transition layer between the water and the sediment. Within this layer, which has a thickness of order 1 cm,...journal article 2006
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Simons, D.G. (author), Snellen, M. (author), Ainslie, M.A. (author)Sound backscattered from the seabed has been measured in a 10x10-nmi2 region of the North Sea, characterized by a variety of bottom types, including mud, sand, and gravel. The backscattering strength measurements are made by a forward- looking sonar, operating at 100 kHz and tilted at an angle of 30 from the horizontal. Fifty bottom-grab samples...journal article 2007
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- Amiri-Simkooei, A. (author), Snellen, M. (author), Simons, D.G. (author) conference paper 2008
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- Simons, D.G. (author), Snellen, M. (author) conference paper 2008
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- Snellen, M. (author), Simons, D.G. (author), Riethmueller, R. (author) conference paper 2008
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- De Plaa, J. (author), Snellen, M. (author), Simons, D.G. (author) conference paper 2008
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- Siemes, K. (author), Snellen, M. (author), Simons, D.G. (author), Hermand, J.P. (author), Meyer, M. (author), Le Gac, J.C. (author) conference paper 2008
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- Amiri-Simkooei, A. (author), Snellen, M. (author), Simons, D.G. (author), Buckingham, M. (author) conference paper 2008
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- El Allouche, N.E. (author), Drijkoningen, G.G. (author), Versteeg, W. (author), Simons, D.G. (author) conference paper 2008
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Siemes, K. (author), Snellen, M. (author), Simons, D.G. (author), Hermand, J.P. (author)Shallow water naval operations require detailed knowledge of the environmental properties. In addition to parameters such as water depth, knowledge about the sediment properties is of high importance for a wide range of operations. In this context, the MREA BP'07 experiment was carried out in the Mediterranean Sea in 2007. Measurements employed...conference paper 2009
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Snellen, M. (author), Siemes, K. (author), Simons, D.G. (author)Nowadays extensive use is made of multibeam echosounders (MBES) for mapping the bathymetry of sea- and river-floors. The MBES is capable of covering large areas in limited time by emitting an acoustic pulse along a wide swathe perpendicular to the sailing direction. The angle and the corresponding two-way travel-time of the received signals are...conference paper 2009
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Amiri-Simkooei, A.R. (author), Snellen, M. (author), Simons, D.G. (author)In a recent work described in Ref. [1], an angle-independent methodology was developed to use the multi-beam echo sounder backscatter (MBES) data for the seabed sediment classification. The method employs the backscatter data at a certain angle to obtain the number of sediment classes and to discriminate between them by applying the Bayes...conference paper 2009
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Simons, D.G. (author), Snellen, M. (author), Siemes, K. (author)Seafloor characterization is important in many fields including hydrography, marine geology, coastal engineering and habitat mapping. The advantage of non-invasive acoustic methods for sediment characterization over conventional bottom grabbing is the nearly continuous versus sparse sensing and the enormous reduction in survey time and costs....conference paper 2009
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Using MBES backscatter strength measurements for assessing a shallow water soft sediment environmentSiemes, K. (author), Snellen, M. (author), Simons, D.G. (author), Hermand, J.P. (author)Shallow water naval operations require detailed knowledge of the environmental characteristics. In this context, the BP’07 experiment was carried out in the Mediterranean Sea, south-east of Elba Island, in 2007. Measurements that were taken during this experiment employ a large set of sensors, thereby providing all information required to fully...conference paper 2009
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Snellen, M. (author), Siemes, K. (author), Simons, D.G. (author)We present a method for accurately estimating the bathymetry from multi-beam echo-sounder (MBES) travel-time measurements in environments with large variations in the water column sound speeds (both temporally and spatially). In this type of environments the water column sound speeds at the time of the MBES transmission are often not known,...conference paper 2009
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Simons, D.G. (author), Bergers, M.M.C. (author), Henrion, S. (author), Hulzenga, J.I.J. (author), Jutte, R.W. (author), Pas, W.M.G. (author), Van Schravendijk, M. (author), Vercruyssen, T.G.A. (author), Wilken, A.P. (author)An autonomous underwater vehicle with a biomechanical propulsion system is a possible answer to the demand for small, silent sensor platforms in many fields. The design of Galatea, a bio-mimetic AUV, involves four aspects: hydrodynamic shape, the propulsion, the motion control systems and payload. The shape of the hull is based on a modified...conference paper 2009
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Amiri-Simkooei, A. (author), Snellen, M. (author), Simons, D.G. (author)A method has recently been developed that employs multi-beam echo-sounder backscatter data to both obtain the number of sediment classes and discriminate between them by applying the Bayes decision rule to multiple hypotheses [ Simons and Snellen, Appl. Acoust. 70, 1258–1268 (2009) ]. In deep water, the number of scatter pixels within the beam...journal article 2009
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- Siemes, K. (author), Snellen, M. (author), Amiri-Simkooei, A.R. (author), Simons, D.G. (author), Hermand, J.P. (author) journal article 2010
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Snellen, M. (author), Siemes, K. (author), Simons, D.G. (author)Acoustic remote sensing techniques for mapping sediment properties are of interest due to their low costs and high coverage. Model-based approaches directly couple the acoustic signals to sediment properties. Despite the limited coverage of the single-beam echosounder (SBES), it is widely used. Having available model-based SBES classification...journal article 2011
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Arntzen, M. (author), Van Veen, T.A. (author), Visser, H.G. (author), Simons, D.G. (author)Aircraft noise annoyance predictions based on traditional tools lack fidelity when modelling a single aircraft flyover. For evaluating annoyance of new procedures, different aircraft types or changing atmospheric conditions, a new modelling approach is necessary. A research effort has been initiated to develop a toolchain that links each of the...conference paper 2011