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921.
922.
A method for the prediction of ocean waves was developed on the basis of the single-parameter growth equation of wind waves, proposed byToba (1978) on the basis of similarity in growing wind waves. The applicability of the method to actual problems was tested by hindcasting the wave characteristics with the method, for two cases with differing time and space scales, one in Kii Channel Approach, Japan, and the other in the North Atlantic Ocean. The results showed that the present method can predict waves within an error of 1.3 m in wave heights, which ranged from 3 to 12 m. 相似文献
923.
- In order to employ cost effective frequency domain analysis for off-shore structures treatment of hydrodynamic loading is essential. Drag and inertia dominated, resonating and antiresonating cases under random sea states are analyzed to highlight the implications and relative merits of four salient linearization techniques. 相似文献
924.
C. Ranz-Guerra 《Geo-Marine Letters》1991,11(3-4):172-173
Mud is a complex mixture of water and solid particles and acoustics can help on its control. The mud layer, as an acoustic
channel, is characterized by its propagation constant relating the wave frequency, the sound velocity, and the energy absorption.
If the input acoustic pulse is known, it is feasible to easily characterize the mud layer as a low pass filter (absorption);
if it is also possible to insonify the mud with sound of both low and high frequencies, the sound speed of the mud mixture
can be evaluated, and the propagation constant is then known. 相似文献
925.
926.
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928.
A comprehensive study of undisturbed, mostly silty clay samples, taken from large-diameter surface cores collected in the North Atlantic and its bordering seas, shows that measurement of the Atterberg limits, water content, specific gravity of grains and grain-size distribution can provide the basis for predicting many seabed geotechnical and geophysical properties which can lead to a quick assessment of environmental conditions. Thus, the sediment compression curve can be reconstructed, acoustic properties assessed, electrical and thermal resistivities deduced and an indication of the shearing forces, which have affected the sediment, inferred. 相似文献
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