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A noise directionality model including variable bathymetry
(NATO. SACLANTCEN, 1997)
In this paper we investigate the noise directionality due to distributed surface sources m several envtronments with a uniformly sloping sea bed. Of particular interest are frequency dependence and the question of the ...
Shallow-water sound transmission measurements taken on the New Jersey continental shelf
(NATO. SACLANTCEN, 1993/08)
Calibrated acoustic measurements were made under calm sea state conditions on the New Jersey shelf near the AMCOR 6010 borehole, a surveyed area with known geophysical properties. The experiment was conducted in 73 m water ...
Low-frequency acoustic measurements in a shallow-water area with a rough sea surface
(NATO. SACLANTCEN, 1975/10)
Surface wave spectra have been measured in the North Sea simultaneously with acoustic investigations using explosive and CW sources. The goal of these experiments was to determine the influence of surface waves to low-frequency ...
Acoustic characterization of a shallow water site
(NATO. SACLANTCEN, 1993/08)
Results are presented from an exercise aimed at providing a low frequency active sonar environmental characterization of a specific shallow water site in the Gulf of Mexico. Downward refracting acoustic transmission and ...
Sound absorption by suspended particulate matter
(NATO. SACLANTCEN, 1997)
A series of experiments has been performed to study the viscous absorption of sound by particulate suspensions typical of those found in coastal waters. The effect due to the particles in the frequency range of 50 - 150 ...
Intensity-range relations for shallow-water sound propagation
(NATO. SACLANTCEN, 1976/04)
Convincing experimental evidence is presented to show that various "decay laws" for the decrease of sound intensity with increasing range can give high-quality representation for shallow water data. However, while a sequence ...
Acoustic signal dispersion and distortion by shallow undersea transmission channels
(NATO. SACLANTCEN, 1997)
The undersea littoral is an adverse medium for acoustic signal transmission to horizontal ranges of many water depths. Reflections and scattering in the bounded, nonhomogeneous channel disperse the arrivaj of received ...
Relative contribution of surface roughness and bottom attenuation to propagation loss in shallow water
(NATO. SACLANTCEN, 1975/10)
A simulation study has been performed to investigate the relative importance of the contributions of surface roughness and bottom attenuation to propagation loss under differing environmental conditionso The NRL normal ...
Geoacoustic inversion using multipath pulse shape
(NURC, 2008/09)
Experimental data, measured in a shallow water region of the Mediterranean Sea, are used to show that the variation of received intensity with time is well described by existing expressions [Harrison and Nielsen, J. Acoust. ...