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Now showing items 537-556 of 882
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Numerical modeling results for mode propagation in a wedge
(NATO. SACLANTCEN, 1987/11)A PE (parabolic equation) code is used to study propagation in a shallow water wedge with a penetrable bottom. Particular attention is given to "wedge modes" that have wave fronts that are arcs of circles centered on the ... -
Numerical modelling of acoustic scattering by smooth inclusions in a layered fluid-solid medium
(NATO. SACLANTCEN, 1997)A boundary integral equation (BIE) method as descnbed for computing the scattering of a monofrequent acoustic field by a smooth, rigid 30 object in a layered range-independent fluid-solid medium. The BIE is discretized ... -
Numerical simulation of the effects of bathymetry on underwater sound propagation using three-dimensional parabolic models
(NATO. SACLANTCEN, 1998/03)Two different three-dimensional parabolic equation (PE) methods are -
Observations of Mediterranean flow into the Black Sea
(NATO. SACLANTCEN, 1997/10)Mediterranean Sea water inflow into the Black Sea is investigated using acoustic and oceanographic data obtained in the Black Sea exit region. The path of Mediterranean water and the resulting spreading on the continental ... -
Observed sound velocity and temperature profiles in the Strait of Gibraltar during the passage of an internal wave
(NATO. SACLANTCEN, 1966/10)Sound velocity and temperature measurements taken from the sea-surface to 350 m depth, close to one spot over a 24-hour period revealed the passage of an internal wave of approximately 60 m amplitude. The effect of this ... -
Obtaining the ocean index of refraction spectrum from the acoustic amplitude fluctuations
(NATO. SACLANTCEN, 1997)The feasibility of using acoustic measurements to determine the properties of a shallow water internal wave field is investigated through numerical simulations. The random intemal wave field is modeled by a generalized ... -
Ocean currents in the Iceland-Faeroe area, measured by a bottom-mounted ADCP
(NATO. SACLANTCEN, 1992/12)Horizontal currents as a function of depth, measured by a bottommounted -
The ocean noise coherence matrix and its rank
(CMRE, 2019/05)An expression for the cross-spectral density matrix of ocean noise naturally separates into a Toeplitz part and a Hankel part [Harrison (2017). J. Acoust. Soc. Am. 141, 2812?2820]. The Toeplitz part is shown to be substantially ... -
Ocean-basin reverberation from large underwater explosions: part 1: source-level and propagation-loss modelling
(NATO. SACLANTCEN, 1975/10)Predicting the reverberant returns from ocean basin reflectors requires describing acoustic source levels for large, conventional underwater explosions, defining the two way propagation loss and signal spreading from the ... -
Ocean-basin reverberation from large underwater explosions: part 2: computer model for reverberation
(NATO. SACLANTCEN, 1975/10)Following detonation of an underwater explosion, sound reverberates from the ocean surface and bottom and from scatterers within the medium. In addition, the boundaries of the ocean basin and obstructions within it, such ... -
Ocean-bottom reflectivity (a point of view)
(NATO. SACLANTCEN, 1975/10)The analysis procedures for extracting bottom loss values from pulsed acoustic signals that have interacted with the ocean bottom do not inherently consider sub-bottom refraction and reflection of sound, which are important ... -
Oceanic layered microstructure and fronts
(NATO. SACLANTCEN, 1971/12)This talk is divided into two parts: one deals with oceanic microstructure, with particular attention to the so-called "layered microstructure"; the other part is concerned with oceanic fronts. As an example of the latter ...