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Ainslie, M.A. (author), de Jong, C.A.F. (author), Robinson, S.P. (author), Lepper, P.A. (author)
To meet the growing demand for carbon-free energy sources, the EU has ambitious plans to increase its capacity for generation of offshore wind power. The UK and Netherlands, for example, plan to increase their offshore power generating capacity, respectively, to 33 and 6 gigawatts by the year 2020. Assuming that this power is generated entirely...
conference paper 2010
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Ainslie, M.A. (author), TNO Defensie en Veiligheid (author)
Sonar performance modelling (SPM) is concerned with the prediction of quantitative measures of sonar performance, such as probability of detection. It is a multidisciplinary subject, requiring knowledge and expertise in the disparate fields of underwater acoustics, acoustical oceanography, sonar signal processing and statistical detection theory...
book 2010
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van Vossen, R. (author), Colin, M. (author), Benders, F. (author), Ainslie, M.A. (author), Eidem, E.J. (author), Chalindar, B. (author), Juhel, B. (author), Dybedal, J. (author), Olsen, G.K. (author), Ivansson, S. (author), Abrahamsson, L. (author)
Accurate environmental information is required for obtaining reliable predictions for the performance of low-frequency active sonar (LFAS) systems. This environmental information is, however, often unreliable or unavailable. For example, the acoustic seabed parameters relevant for the scattering and reflection of sound at the seabed are commonly...
conference paper 2011
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Juhel, B. (author), Cristol, X. (author), Chalindar, B. (author), Dybedal, J. (author), Eidem, E.J. (author), Ivansson, S. (author), van Vossen, R. (author), Ainslie, M.A. (author), Andersson, B.L. (author), Benders, F.P.A. (author), Colin, M.E.G.D. (author), Olsen, G.K. (author), Pihl, J. (author)
This paper presents the European Defence Agency project called “RUMBLE 2” carried out with contribution of several European organizations: TUS in France, TNO in the Netherlands, KDS and FFI in Norway, FOI in Sweden. The objective was to assess the capability of an operational Low Frequency Active Sonar (LFAS) to estimate bottom parameters in...
conference paper 2011
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Ainslie, M.A. (author), Harrison, C.H. (author), Zampolli, M. (author)
Previously published equations for the time dependence of the echo and reverberation in a Pekeris waveguide are combined with an expression derived for surface-generated noise. These closed form solutions are applied to the calculation of signal to reverberation ratio and signal to total background ratio for three CW pulses with centre...
conference paper 2011
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Zampolli, M. (author), Ainslie, M.A. (author), van Zon, T. (author)
Ping-to-ping variations in echo level can be caused by time variations in sonar parameters (source level, orientation), target aspect, relative and absolute motion of sonar and target, and time varying environment (e.g. surface waves). Quantifying and understanding such fluctuations are important, since they enable an appropriate choice of...
conference paper 2011
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Zampolli, M. (author), Ainslie, M.A. (author)
In April 2010, a symposium in Memory of David Weston was held at Clare College in Cambridge (UK). International researchers from academia and research laboratories met to discuss two sets of test problems for sonar performance models, one aimed at understanding mammal echolocation sonar („Problem AI‟), and the other at benchmarking low frequency...
conference paper 2011
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Abrahamsson, L. (author), Andersson, B.L. (author), Ivansson, S. (author), Pihl, J. (author), Ainslie, M.A. (author), Benders, F.P.A. (author), Chalindar, B. (author), Colin, M. (author), Cristol, X. (author), Dybedal, J. (author), Eidem, E.J. (author), Juhel, B. (author), Olsen, G.K. (author), van Vossen, R. (author)
Reverberation is a problem for active sonar operating in shallow waters, reducing detection probabilities and introducing false alarms. Within the European Defence Agency project Rumble-2, a demonstrator system has been developed for ”through the sensor” measurement of the bottom parameters needed to predict active sonar detection performance....
conference paper 2011
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Ainslie, M.A. (author), Dekeling, R.P.A. (author)
Cumulative acoustic exposure is used as an indicator for the risk of negative impact to animals as a consequence of exposure to underwater sound. The free-field energy of a single source, defined as the total acoustic energy that would exist in the source’s free field, is shown to be closely related to the total cumulative exposure added over a...
conference paper 2011
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Ainslie, M.A. (author), de Jong, C.A.F. (author)
Early human interest in ambient noise in the sea, especially during and after the Second World War, resulted from its effect on limiting the performance of military search sonar [Urick 1983]. While that interest continues, it is now accompanied by non-military uses of underwater sound, such as navigation, fisheries, oceanography and seismic...
conference paper 2011
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van Vossen, R. (author), Ainslie, M.A. (author)
Reliable predictions of sea-surface backscattering strength are required for sonar performance modeling. These are, however, difficult to obtain as measurements of sea-surface backscattering are not available at small grazing angles relevant to low-frequency active sonar (1-3 kHz). Accurate theoretical predictions of scattering strength require...
article 2011
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Ainslie, M.A. (author), Leighton, T.G. (author)
In [M. A. Ainslie & T. G. Leighton, Underwater Acoustic Measurements (Heraklion, Crete, 2007), pp 571-576], the authors described a discrepancy between the radiation damping coefficients in the models due to Weston and to Medwin describing the scattering cross-section of a single spherical bubble. The resolution of that discrepancy [M. A....
conference paper 2011
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Ainslie, M.A. (author), Leighton, T.G. (author)
Perhaps the most familiar concepts when discussing acoustic scattering by bubbles are the resonance frequency for bubble pulsation, the bubbles' damping, and their scattering and extinction cross-sections, all of which are used routinely in oceanography, sonochemistry, and biomedicine. The apparent simplicity of these concepts is illusory: there...
article 2011
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Sertlek, H.O. (author), Ainslie, M.A. (author)
Concern about possible impact of human activity on marine life has led to regulation in the USA [1,2] and the EU [3].The EU’s Marine Strategy Framework Directive [3] requires member states to achieve Good Environmental Status (GES) by 2020. Descriptor 11 of GES is “Introduction of energy, including underwater noise, is at levels that do not...
conference paper 2012
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von Benda-Beckmann, A.M. (author), van der Zwan, T. (author), van Riet, M.W.G. (author), Benders, F.P.A. (author), Ainslie, M.A. (author), te Raa, L.A. (author)
SAKAMATA is a risk assessment and mitigation tool developed by TNO and used by the Royal Netherlands Navy. It supports the user in planning and carrying out active sonar operations in an environmentally responsible way. Recently, a new version has been developed, which makes it possible to quantify the number of marine mammals affected, taking...
conference paper 2012
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Dol, H.S. (author), Colin, M.E.G.D. (author), Ainslie, M.A. (author), van Walree, P.A. (author), Janmaat, J. (author)
Sea surface scattering by wind-generated waves and bubbles is regarded to be the main non-platform related cause of the time variability of shallow acoustic communication channels. Simulations for predicting the quality of acoustic communication links in such channels thus require adequate modeling of these dynamic sea-surface effects. It is...
conference paper 2012
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Cristol, X. (author), Jespers, S. (author), Chalindar, B. (author), Juhel, B. (author), Dybedal, J. (author), Eidem, E.J. (author), Ivansson, S. (author), van Vossen, R. (author), Ainslie, M.A. (author), Andersson, B.L. (author), Colin, M.E.G.D. (author), Pihl, J. (author)
The European Defence Agency project RUMBLE-2 (ref.[1]) offered the opportunity for investigating experimentally acoustic reverberation at about 1.kHz, under grazing incidence (less than about 20°), from very porous clayey seafloors of a continental shelf (mean grain size spanning from about 7 to 10 in  units); the instrument was an operational,...
conference paper 2012
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Abrahamsson, L. (author), Andersson, B.L. (author), Ivansson, S. (author), Pihl, J. (author), Chalindar, B. (author), Cristol, J.X. (author), Juhel, B. (author), Eidem, E.J. (author), Dybedal, J. (author), Olsen, G.K. (author), Ainslie, M.A. (author), Benders, F.P.A. (author), Colin, M.E.G.D. (author), van Vossen, R. (author)
An operational low-frequency active sonar system has been used in the EDA (European Defence Agency) project Rumble-2 to collect reverberation data at sea trials in the North Sea. Using a fast ray model for the forward computations, the reverberation data are inverted to determine bottom parameters: Lambert back-scattering parameter μ and sound...
conference paper 2012
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Ainslie, M.A. (author), de Jong, C.A.F. (author), Robinson, S.P. (author), Lepper, P.A. (author)
To meet the growing demand for carbon-free energy sources, the European Union (EU) has ambitious plans to increase its capacity for generation of offshore wind power. The United Kingdom and The Netherlands, for example, plan to increase their offshore power-generating capacity to 33 and 6 GW, respectively, by the year 2020. Assuming that this...
bookPart 2012
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Lepper, P.A. (author), Robinson, S.P. (author), Ainslie, M.A. (author), Theobald, P.D. (author), de Jong, C.A.F. (author)
The installation of offshore wind farms in European waters and the scale of the planned activity have led to concern over the generation of noise and its potential impact on marine life. Much of this concern is centered around the noise generated by pile driving, which is used for the installation of the turbine foundations, and its potential...
bookPart 2012
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