Accuracy and precision of fish-count data from a "dual-frequency identification sonar" (DIDSON) imaging system     

Holmes  John A.; Cronkite  George M.W.; Enzenhofer  Hermann J.; Mulligan  Timothy J. 《ICES Journal of Marine Science》2006,63(3):543-555

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减少航道外波浪集聚对策研究   总被引：3，自引：0，他引：3  

李思源  白志刚  王广聚 《海洋技术学报》2002,21(3):56-61

进港航道开挖引起波能重新分布 ,导致航道外近区域波能聚集 ,波高增大 ,从而影响防波堤稳定及港内泊稳条件。文章介绍了 Boussinesq方程的推导过程和发展过程 ,基于深水和缓变地形的色散关系 ,建立了波浪数学模型。该模型可用于研究深水和浅水地区波浪的浅水变形、折射、绕射和反射。并提出了减少波能聚集、降低堤前波高的多种措施。结合大窑湾港实际工程 ,经过多方面的数物模比选 ,利用数学模型优化出一种可行的喇叭口航道开挖方案并付诸实施 ,降低了防波堤的堤前波高 ,满足了预期的设计要求。  相似文献   

Estimation of gillnet and hook selectivity using log-linear models   总被引：5，自引：0，他引：5  

Millar  Russell B.; Holst  Rene 《ICES Journal of Marine Science》1997,54(3):471-477

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基于GIS的无人机地面监控系统的设计与实现   总被引：3，自引：0，他引：3  

熊自明  葛文 《海洋测绘》2007,27(4):54-56

在分析无人机领域飞行数据特征的基础上,设计实现了一套功能较为完善的无人机地面监控系统。该系统主要完成了无人机飞行状态实时显示、航线规划和航线回放等功能模块。系统借助于G IS技术,导入矢量形式的电子地图,利用丰富的地理信息来辅助实现无人机的地面监控,在V isual C 6.0开发环境下利用基于异步方式和事件驱动方式的串口通信实现了系统与地面控制站的通信,利用地图控制文件实现了地图数据的调度,利用显示缓存实现了视图实时刷新。经过实际联调,系统运行良好,实用性较好。  相似文献   

GPS数据采集技术及其在海洋调查中的应用   总被引：1，自引：0，他引：1  

邱雨生  陈敏  刘广山 《台湾海峡》2003,22(3):354-359

本文应用VB6．0开发了智能化的GPS数据采集软件．对该软件的功能进行了简单的介绍，同时对一些关键技术作了较详细的描述。利用该软件、GPS接收机及PC机的组合，可对走航式测量仪器(或移动设备)进行实时定位并保存定位记录，且大大减少一些不必要的数据，使得软件更为实用。  相似文献   

一种基于正交频分复用的高速水声通信技术的研究     

蔡慧  蔡惠智  刘云涛  邓红超 《海洋技术学报》2007,26(3):44-47

OFDM(正交频分复用)是一种适合于在多径衰落和受限带宽信道中进行高速传输的技术。论文把OFDM技术应用于高速水声通信中,设计了一套基于OFDM的高速水声通信系统,阐述了OFDM水声通信系统中同步和信道估计的方法。海上试验证明了系统的有效性。  相似文献   

TSDV: A GIS tool for inspecting trawl survey data     

Fortunati  L.; Garofalo  G.; Demontis  R. 《ICES Journal of Marine Science》2002,59(1):168-178

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A Method of Coding and Decoding in Underwater Image Transmission     

程恩 《海洋通报(英文版)》2001,3(2)

A new method of coding and decoding in the system of underwater image transmission is introduced, including the rapid digital frequency synthesizer in multiple frequency shift keying,image data generator, image grayscale decoder with intelligent fuzzy algorithm, image restoration and display on microcomputer.  相似文献   

A New Methodology for Incorporating Tide Gauge Data in Sea Surface Topography Models   总被引：1，自引：0，他引：1  

J. C. Iliffe  M. K. Ziebart  J. F. Turner 《Marine Geodesy》2007,30(4):271-296

As part of the Vertical Offshore Reference Frames (VORF) project sponsored by the U. K. Hydrographic Office, a new model for Sea Surface Topography (SST) around the British Isles has been developed. For offshore areas (greater than 30 km from the coast), this model is largely derived from satellite altimetry. However, its accuracy and level of detail have been enhanced in coastal areas by the inclusion of not only the 60 PSMSL tide gauges with long-term records around the coasts of the United Kingdom and Ireland but also some 385 gauges established at different epochs and for different observation spans by the U. K. Admiralty. All tide gauge data were brought into a common reference frame by a combination of datum models and direct GPS observations, but a more significant challenge was to bring all short-term sea level observations to an unbiased value at a common epoch. This was achieved through developing a spatial-temporal correlation model for the variations in mean sea level around the British Isles, which in turn meant that gauges with long-term observation spans could be used as control points to improve the accuracy of Admiralty gauges. It is demonstrated that the latter can contribute point observations of mean sea level (MSL) with a precision of 0.078 m. A combination of least squares collocation and interpolation was developed to merge the coastal point and offshore gridded data sets, with particular algorithms having to be developed for different configurations of coastal topology. The resulting model of sea surface topography is shown to present a smooth transition from inshore coastal areas to offshore zones. Further benefits of the techniques developed include an enhanced methodology for detecting datum discontinuities at permanent tide gauges.  相似文献   

Unintended and perverse consequences of ignoring linkages in fisheries systems     

Degnbol  Poul; McCay  Bonnie J. 《ICES Journal of Marine Science》2007,64(4):793-797

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