Results 251 to 260 of about 856,677 (287)

Reflection of long waves from a “nonreflecting” bottom profile

Fluid Dynamics, 2008
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Didenkulova, I. I., Zahibo, N., Pelinovsky, E. N.   +2 more
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Surface-Reflected/Bottom-Reflected Ray Transmissions in a Divergent Channel

The Journal of the Acoustical Society of America, 1968
Surface-reflected/bottom-reflected ray transmissions in a divergent channel are studied when the sound velocity decreases linearly with depth. The sound source and receiving point are located on the bottom. Under certain simplifying assumptions, ray geometry is examined, and conditions are given under which a ray is surface reflected, refracted, or a ...
Melvin J. Jacobson, J. Thomas Warfield
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Approximate methods for reflection from solid bottoms.

The Journal of the Acoustical Society of America, 1992
The acoustic reflection coefficient for a solid ocean bottom can be well approximated by assuming an ‘‘equivalent fluid’’ bottom of suitably chosen parameters. The density and attenuation of the equivalent fluid are different from the corresponding parameters of the solid.
Z. Y. Zhang, C. T. Tindle
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Spectra and Waveforms of Bottom-Reflected Pulses

The Journal of the Acoustical Society of America, 1966
A mathematical model considering reflection as a reradiation phenomenon has been constructed. The model allows computation of the spectrum and waveform of a reflected pulse in terms of the incident plane-wave pulse or its spectrum, the reradiation characteristics of the reflector, the incident direction, and the reradiation direction. Bottom reflection
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Interference in Reflections from the Ocean Bottom and Subbottom

The Journal of the Acoustical Society of America, 1961
A strong interference pattern has been observed in the reflection of monochromatic pings from the ocean bottom. The experiment was performed in the Gulf of Mexico at 24°16′N, 85°15′W. The acoustic pings had a frequency of 120.5 cps and a length of 0.12 sec and were repeated every sec. The transmitter was at a depth of 75 ft and the receiver at 3000 ft.
M. Vertner Brown, James Ricard
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Reflectivity of the ocean bottom at low frequency

The Journal of the Acoustical Society of America, 1978
The theoretical reflectivity of the ocean bottom estimated from a model composed of fluid sediment layers is misleading because the effects of shear propagation are ignored. Reflectivity computations which include the effects of shear may be made using Thomson–Haskell matrix theory.
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Reflection of Sound from Coastal Bottoms

The Journal of the Acoustical Society of America, 1959
A number of sea trips were made during the summer of 1950 and through the spring of 1951 to measure 1-kc sound-reflection losses over several bottoms as a function of the grazing angle. The results agree with Rayleigh's expressions as modified by R. W. Morse to allow for the attenuation in the bottom.
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Marine Sediment Attenuation and Ocean-Bottom-Reflected Sound

The Journal of the Acoustical Society of America, 1964
The attenuation of sound in marine sediments is shown to depend on the first power of the frequency for a range of 100–1000 cps, and the relation between sediment attenuation and ocean-bottom reflectivity is discussed. The reflection process is approximated by a three-layer fluid model, with attenuation in the second and third layers.
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Studies of the ocean-bottom reflection coefficient at angles of total internal reflection

Acoustical Physics, 2002
For practical-purpose studies in underwater acoustics, a new method is proposed to determine the bottom reflection coefficient on the basis of multiple bottom-surface reflections. The method allows one to obtain the angular dependence of the bottom reflection coefficient at grazing angles from several degrees to several tens of degrees in the audio and
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Negative bottom loss, critical-angle shift, and the interpretation of the bottom reflection coefficient

The Journal of the Acoustical Society of America, 1977
The determination of the acoustical properties of the ocean bottom is a formidable task. One method is the seismic reflection method. Some of the limitations inherent in the interpretation of the reflected field are described. These include the dependence of the measurement on the complete geometry of the experiment, the occurrence of negative bottom ...
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