Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)最新文献_第6页

Status of underwater technology in Taiwan 台湾水下技术现状

Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869) Pub Date : 2004-04-20 DOI: 10.1109/UT.2004.1405455

Y. Chen

引用次数: 1

A possible mechanism for acoustic triggering of decompression sickness symptoms in deep-diving marine mammals 深海海洋哺乳动物减压病症状的声触发可能机制

Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869) Pub Date : 2004-04-20 DOI: 10.1109/UT.2004.1405608

J. Potter

{"title":"A possible mechanism for acoustic triggering of decompression sickness symptoms in deep-diving marine mammals","authors":"J. Potter","doi":"10.1109/UT.2004.1405608","DOIUrl":"https://doi.org/10.1109/UT.2004.1405608","url":null,"abstract":"An interest in plausible mechanisms for significant acoustic impact on some species of marine mammals at receive levels significantly below that currently anticipated to cause direct physical trauma has arisen in response to questions of how the operation of sonars may have contributed to mass beaching events of beaked whales. Resonance in cavities and other specific structures was at one time proposed as a mechanism, but after some scrutiny this now appears unlikely. Rectified diffusion was posed as another candidate, but has been demonstrated to be significant only at relatively high pressure levels, exceeding receive levels anticipated in observed beaching circumstances. We examine an alternative proposition; that pre-existing micro-bubbles that are normally stabilized and which do not normally permit gas exchange across their walls can be acoustically activated so that continued growth is supported through static diffusion from super-saturated tissues in the absence of an acoustic field. The proposed mechanism would explain why micro bubbles (believed to be normally present in mammalian tissues) do not grow and cause decompression sickness (DCS) in healthy deep divers with super-saturated tissues, why these micro bubbles do not collapse under the Laplace pressure exerted by surface tension in unsaturated tissues, and why long-duration, deep diving cetaceans such as beaked whales appear to be particularly vulnerable to anthropogenic acoustic exposures. Numerical results for bubble growth modelled according to the treatments of Crum and Mao under tissue super-saturations of 200-300% (an appropriate range for deep-diving marine mammals on surfacing) show that if micro-bubble gas exchange could be activated acoustically, even by only a very brief exposure, this would result in subsequent bubble growth by static gas diffusion so that within 10 minutes their size would be sufficient to cause symptoms of decompression sickness (DCS)","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"42 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117246919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

The ambient noise fluctuation and directionality study in South China Sea 南海海域环境噪声波动与方向性研究

Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869) Pub Date : 2004-04-20 DOI: 10.1109/UT.2004.1405564

Ruey‐Chang Wei, J. Lynch, A. Newhall, Hsiang‐Chih Chan, Chih-Sheng Liu, Po‐Chang Lin

{"title":"The ambient noise fluctuation and directionality study in South China Sea","authors":"Ruey‐Chang Wei, J. Lynch, A. Newhall, Hsiang‐Chih Chan, Chih-Sheng Liu, Po‐Chang Lin","doi":"10.1109/UT.2004.1405564","DOIUrl":"https://doi.org/10.1109/UT.2004.1405564","url":null,"abstract":"This study is based upon the vertical line array (VLA) in South China Sea experiment of the Asian Seas International Acoustic Experiment (ASIAEX), dated from May 3, 2001 to May 16, 2001, in which the ambient noise in shallow water was measured. We present two analyses of ambient noise, the fluctuation and directionality. The fluctuation of ambient noise level is measured by using Fourier analysis, and we did the similar analysis on static water pressure and temperature variation, the acoustic data has shown obvious K1 and M2 tidal periods. Typhoon Cimaron passed the experimental area during the experiment, which increased ambient noise levels at higher frequency (above 400 Hz) and affected the tidal fluctuations. Accordingly, the threshold frequency of the ambient noise levels affected by the wind wave is about 400 Hz. On the other hand, we use beamforming method to calculate the vertical directionality of shallow water ambient noise. The results show that distant shipping noise was observed near the horizontal angles, and surface noise occurred at high grazing angles. We also noted the phenomena of \"noise notch\" appeared at some duration, and the environmental effects (especially sound speed profile) on the notch were discussed in the end part of this paper. The boundary effects of shallow water have significant impacts on sound propagation, thus strong time variation of ambient noise directionality was recorded.","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"07 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127324732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Improvement on an inertial-Doppler navigation system of underwater vehicles using a complementary range sonar 利用互补距离声纳改进水下航行器惯性多普勒导航系统

Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869) Pub Date : 2004-04-20 DOI: 10.1109/UT.2004.1405508

Pan-Mook Lee, Sea-moon Kim, B. Jeon, Hyun-Taek Choi, Chong-moo Lee

{"title":"Improvement on an inertial-Doppler navigation system of underwater vehicles using a complementary range sonar","authors":"Pan-Mook Lee, Sea-moon Kim, B. Jeon, Hyun-Taek Choi, Chong-moo Lee","doi":"10.1109/UT.2004.1405508","DOIUrl":"https://doi.org/10.1109/UT.2004.1405508","url":null,"abstract":"This work presents an improvement of an inertial-Doppler underwater navigation system for unmanned underwater vehicles (UUV) using a complementary range sonar. The inertial-Doppler navigation system is generally based on an inertial measurement unit (IMU) and a Doppler velocity log (DVL) accompanying a magnetic compass and a depth sensor. Although conventional navigation systems update bias errors of the inertial sensors, scale effects of the DVL, the estimated position slowly drifts as time passes. This paper proposes a measurement model with additional range sonar to improve the performance of the IMU-DVL navigation system for underwater vehicles. The proposed navigation model based on inertial navigation systems includes the scale effects, the bias errors of the DVL, and the error model of the range sonar, where the order of the system states is 21. An extended Kalman filter was adopted to propagate the error covariance, updated the measurement errors and correct the state equation when the external measurements are available. Simulation conducted with the 6-d.o.f. equations of motion of an AUV in lawn-mowing survey mode illustrates the effectiveness of the IMU-DVL navigation system assisted by the additional range measurement.","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116074454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 16

AUV systems research at the NRC-IOT: an update NRC-IOT的AUV系统研究:最新进展

Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869) Pub Date : 2004-04-20 DOI: 10.1109/UT.2004.1405480

C. Williams

{"title":"AUV systems research at the NRC-IOT: an update","authors":"C. Williams","doi":"10.1109/UT.2004.1405480","DOIUrl":"https://doi.org/10.1109/UT.2004.1405480","url":null,"abstract":"This paper provides general information on autonomous underwater systems (vehicles). The associated ideas lead directly to considerations that affect the design of fully-autonomous vehicles. We include a discussion of some of the engineering, logistical and systems-integration aspects of autonomous operations, including the use of multiple vehicles in a coordinated \"fleet\". We outline some of the technical challenges associated with working within a limited energy budget and mention some possible strategies for vehicle-to-vehicle communications and for vehicle-network configurations and management. The results from this research permit the planners and developers of autonomous vehicle systems to better allocate such limited assets in order to provide more effective operations in hazardous environments. We describe the design of one instance of such a vehicle, in the form of a highly-manoeuvrable autonomous underwater vehicle (AUV). We also describe our initial successes and lessons learned, and, our plans for subsequent development of the AUV \"C-SCOUT\" and its role as a prototype member of a small \"fleet\" of AUVs. We describe some parallel work-in-progress that has commercial application in support of the Canadian East Coast offshore oil and gas industry. This work involves a single AUV carrying suitable sensors to detect and quantify the presence of certain chemicals in ocean water samples.","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123424651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 17

Navigation and control for a test bed AUV-SNUUV I AUV-SNUUV I试验台导航与控制

Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869) Pub Date : 2004-04-20 DOI: 10.1109/UT.2004.1405485

Kihun Kim, H.S. Choi

引用次数: 5

BEM/FEM simulation of acoustic field and shape optimization of submarine using neural network and genetic algorithm 基于神经网络和遗传算法的潜艇声场边界元/有限元仿真及形状优化

Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869) Pub Date : 2004-04-20 DOI: 10.1109/UT.2004.1405578

M. Durali, A. Delnavaz

引用次数: 2

Seabed characterization using normalized backscatter data by best estimated grazing angles 利用归一化后向散射数据通过最佳估计掠射角进行海底表征

Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869) Pub Date : 2004-04-20 DOI: 10.1109/UT.2004.1405514

T. Hou, L. Huff

{"title":"Seabed characterization using normalized backscatter data by best estimated grazing angles","authors":"T. Hou, L. Huff","doi":"10.1109/UT.2004.1405514","DOIUrl":"https://doi.org/10.1109/UT.2004.1405514","url":null,"abstract":"Today's multibeam echo-sounders (MBES) provide detailed bathymetric information that allows local slope corrections to be made to the concurrently collected acoustic backscatter imagery, thus improving the seabed characterization possibilities. Despite the availability of these data, local-slope corrections are not typically applied in the backscatter-processing scheme. We describe an approach that compensates backscatter for local slope by taking into account the vessel yaw, pitch and roll angles when determining the beam incident angle at the sea floor, and using all the available closest neighbor soundings within a certain radius. The normal of the 3D local curvature at each beam location is then calculated by a weighted least squares fit to the surrounding surface. The proposed method can use all the available geometric information from the co-registered depths and backscatter strengths either from a single survey line, or multiple survey lines, if overlapping lines exist. With the actual grazing angles computed, the transmitting and receiving beam patterns can be estimated to process and analyze the survey data for the extraction of seafloor property information in regions of complex topographic relief. As an example of this research, a backscatter image created from the multibeam data collected using a Simrad EM1000 sonar system on the mid-outer continental shelf off the New Jersey Margin, was normalized by the true grazing angles. When normalized, a better correlation between the independently measured grain size and backscatter was found, than with non-normalized backscatter data. With backscatter vs. grazing angle curve from a Gulf of Mexico multibeam survey, backscatter model parameter optimization was pursued in order to characterize the seabed by their spatial variations.","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123725670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

A dynamic vision system for tracking and localization of underwater objects 一种用于水下目标跟踪和定位的动态视觉系统

Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869) Pub Date : 2004-04-20 DOI: 10.1109/UT.2004.1405551

S. Cheng, Huai-Wen Hsu, Shiao-Chung Cheng

引用次数: 1

An Obstacle Avoidance System for an autonomous underwater vehicle 自主水下航行器避障系统

Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869) Pub Date : 2004-04-20 DOI: 10.1109/UT.2004.1405482

M. Eichhorn

引用次数: 20