排序方式： 共有3条查询结果，搜索用时 0 毫秒
1
1.
Dushaw B.D. Howe B.M. Mercer J.A. Spindel R.C. Baggeroer A.B. Menemenlis D. Wunsch C. Birdsall T.G. Metzger K. Clark C. Colosi J.A. Comuelle B.D. Dzieciuch M. Munk W. Worcester P.F. Costa D. Forbes A.M.G. 《Oceanic Engineering, IEEE Journal of》1999,24(2):202-214
Acoustic signals transmitted from the ATOC source on Pioneer Seamount off the coast of California have been received at various sites around the Pacific Basin since January 1996. We describe data obtained using bottom-mounted receivers, including US Navy Sound Surveillance System arrays, at ranges up to 5 Mm from the Pioneer Seamount source. Stable identifiable ray arrivals are observed in several cases, but some receiving arrays are not well suited to detecting the direct ray arrivals. At 5-Mm range, travel-time variations at tidal frequencies (about 50 ms peak to peak) agree well with predicted values, providing verification of the acoustic measurements as well as the tidal model. On the longest and northernmost acoustic paths, the time series of resolved ray travel times show an annual cycle peak-to-peak variation of about 1 s and other fluctuations caused by natural oceanic variability. An annual cycle is not evident in travel times from shorter acoustic paths in the eastern Pacific, though only one realization of the annual cycle is available. The low-pass-filtered travel times are estimated to an accuracy of about 10 ms. This travel-time uncertainty corresponds to errors in range- and depth-averaged temperature of only a few millidegrees, while the annual peak-to-peak variation in temperature averaged horizontally over the acoustic path and vertically over the upper 1 km of ocean is up to 0.5°C 相似文献
2.
Lynch J.F. Colosi J.A. Gawarkiewicz G.G. Duda T.F. Pierce A.D. Badiey M. Katsnelson B.G. Miller J.E. Siegmann W. Ching-Sang Chiu Newhall A. 《Oceanic Engineering, IEEE Journal of》2006,31(1):33-48
Results and recommendations for evaluating the effects of fine-scale oceanographic scattering and three-dimensional (3-D) acoustic propagation variability on the Effects of Sound on the Marine Environment (ESME) acoustic exposure model are presented. Pertinent acoustic scattering theory is briefly reviewed and ocean sound-speed fluctuation models are discussed. Particular attention is given to the nonlinear and linear components of the ocean internal wave field as a source of sound-speed inhomogeneities. Sound scattering through the mainly isotropic linear internal wave field is presented and new results relating to acoustic scattering by the nonlinear internal wave field in both along and across internal wave wavefront orientations are examined. In many cases, there are noteworthy fine-scale induced intensity biases and fluctuations of order 5-20 dB. 相似文献
3.
1