水下光学无线通信的海水信道特性研究     

隋美红  于新生  刘西锋  周章国 《海洋科学》2009,33(6):80-85

提出了将具有比声学高达几倍的数据通信速率,良好的安全性和隐蔽性的光学无线通信技术应用于海军、海洋科学研究和水下工程等领域,实现高速率的水下无线通信技术实现海量数据的信息交换.基于生物光学特性的水下光学信道模型,建立了水下光学通信系统性能分析方法.并对基于发光二极管(LED)的水下光学无线通信系统进行了仿真,其结果表明所建立的方法可以进行各种海域水质环境的模拟,便于时水下光学无线通信系统性能进行预测评估,为水下光学无线通信系统的设计方案的评估提供了依据.  相似文献   

港珠澳大桥水下结构物的多手段探测   总被引：1，自引：0，他引：1       下载免费PDF全文

洪四雄  刘庆东  陈一超  张春添 《海洋测绘》2009,29(5):71-73

介绍了利用侧扫声纳、浅地层剖面仪和磁力仪开展港珠澳大桥水下结构物的探测方法和过程,并将探测的结果与调查收集的资料比较,分析水下结构物的分布情况,不同探测方法得出的结果也可以相互印证。  相似文献   

Mapping and initial dilution estimation of an ocean outfall plume using an autonomous underwater vehicle     

P.A. Ramos  M.V. Neves  F.L. Pereira 《Continental Shelf Research》2007

A monitoring mission to study the shape and estimate initial dilution of the S. Jacinto outfall plume using an autonomous underwater vehicle (AUV) was performed on July 30, 2002. In order to reduce the uncertainty about plume location and to concentrate the vehicle mission only in the hydrodynamic mixing zone, outputs of a near-field prediction model, based on effective real-time in situ measurements of current speed and direction and density stratification, were opportunistically used to specify in real time the mission transects. The surface characteristics of the outfall plume were found to be influenced strongly by the relatively weak stratification and low current velocities. Dilution was estimated using a temperature–salinity (TS-) diagram with initial mixing lines between wastewater and ambient waters. Effluent dilutions were at least 30:1 in this study. In order to efficiently map the plume dispersion we applied the least-squares collocation method technique. Our results demonstrate that AUVs can provide high-quality measurements of physical properties of effluent plumes in a quite effective manner and valuable considerations about the initial mixing processes under real oceanic conditions can be further investigated.  相似文献   

钦州湾水下动力地貌特征   总被引：1，自引：0，他引：1  

黎广钊  梁文  刘敬合 《地理与地理信息科学》2001,17(4):70-75

钦州湾水下动力地貌主要有潮间浅滩、河口沙坝、潮沟、潮流沙脊、潮流冲刷深槽、水下拦门浅滩、水下斜坡。该文阐述钦州湾的入海河流、潮汐、潮流、波浪等水动力的基本特征 ,分析水下地貌类型的形成及其空间分布和沉积物组成 ,并探讨动力地貌形成原因与机理及海岸动态变化趋势。  相似文献   

上海附近地区水域的地质灾害及其对工程建筑的影响   总被引：1，自引：1，他引：1  

孙家淞  陈庆 《上海国土资源》1993,(2):17-26

本区水域的地质灾害分为直接的、潜在的和人为的三种,类型有冲刷槽、滑坡、活动沙波和沙脊、不稳定岸坡、快速侵蚀和堆积,浅滩和暗礁,埋藏古河道、古洼地、埋藏基岩、含气沉积物、“鸡蛋壳”地层,断层和地震,人为障碍物等。本文讨论了各类水域地质灾害的分布、特征、对工程建筑的影响和防治措施。  相似文献   

Şarköy-Mürefte 1912 Earthquake's Tsunami, extension of the associated faulting in the Marmara Sea, Turkey     

Y. Altınok  B. Alpar  C. Yaltırak 《Journal of Seismology》2003,7(3):329-346

The historical tsunamis in the Marmara Seawere mainly caused by earthquakes andneeded to be documented. Following 1999Izmit earthquake occurred at the EasternMarmara region, a complete inventory ofactive faults in the Marmara Sea regionbecame much more stressed. To the west, thelatest event is 09.08.1912arköy-Mürefte Earthquake. Itoccurred on the active Ganos Fault zone andwas one of the largest earthquakes in theBalkans. The eastern termination of theassociated faulting is in the deep WestMarmara Trough, westernmost of thesuccessive basins forming the Marmara Sea.On the basis of recent multibeam bathymetryand seismic reflection data, estimatedtotal length of the surface rupture isabout 56 km. The historical data reviewedfrom library and archive documents,geological field surveys and offshoregeophysical investigations have shown thatthe 1912 earthquake produced a tsunami. Inaddition a seabed dislocation, the sourceof 1912 tsunami can also be assigned to thesediment slumps appearing in the form ofechelon landslide prisms along the southernslopes of the West Marmara Trough.  相似文献   

Using unmanned underwater vehicles as research platforms in coastal ocean studies     

Kendall L.Carder  David K.Costello 《中国海洋大学学报(英文版)》2003,2(2):211-217

The advantages of using unmanned underwater vehicles in coastal ocean studies are emphasized. Two types of representative vehicles, remotely operated vehicle (ROV) and autonomous underwater vehicle (AUV) from University of South Florida, are discussed. Two individual modular sensor packages designed and tested for these platforms and field measurement results are also presented. The bottom classification and albedo package, BCAP, provides fast and accurate estimates of bottom albedos, along with other parameters such as in-water remote sensing reflectance. The real-time ocean bottom optical topographer, ROBOT, reveals high-resolution 3-dimentional bottom topography for target identification. Field data and results from recent Coastal Benthic Optical Properties field campaign, 1999 and 2000, are presented. Advantages and limitations of these vehicles and applications of modular sensor packages are compared and discussed.  相似文献   

差分GPS水下立体定位系统   总被引：15，自引：3，他引：15  

王权  程鹏飞  章传银  王泽民  蔡艳辉  丁剑 《测绘科学》2006,31(5):18-19,21

差分GPS水下立体定位系统包括GPS差分基准站、GPS浮标、水下收发机、船基控制中心四部分。差分基准站提供GPS差分改正,实现浮标内置GPS高精度实时定位。GPS浮标完成水上和水下的集成,检测水下收发机发射的定位信号并测量信号到达的时间,同时将各种数据发送到船基控制中心。船基控制中心接收各个浮标的数据后实时解算水下收发机的位置,同时将结果发送给水下收发机。本文首先对系统的总体构成和各个部分的功能进行了介绍,然后详细推导了系统定位算法,最后结合系统试验情况给出了系统试验精度统计结果。  相似文献   

瞬态弹性波散射的变换域积分方程法          下载免费PDF全文

时刚  高广运 《地震工程学报》2006,28(3):225-228

针对瞬态弹性波散射的问题,从弹性动力学问题的积分表示定理出发,采用Laplace变换的方法,得到了变换域内均质体位移场的积分方程表示;在此基础上推导了适合瞬态弹性波对异质体散射求解的变换域位移场积分方程。  相似文献   

基于克隆选择算法的障碍布局分配问题研究     

梁勤欧 《武汉大学学报(信息科学版)》2007,32(8):744-747

应用克隆选择算法(clonal selection principle,CLONALG),结合其他模型算法,提出了一套解决障碍布局分配问题的简化流程,并用实验进行了验证,得到了满意的效果。  相似文献