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介绍了一个通过移动卫星Inmarsat-Mini C通信手段进行远程遥控和数据传输的无人值守的自动监测系统。具体内容包括Inmarsat-Mini C系统介绍、遥控系统结构和其工作流程介绍、遥控系统对Mini C业务的具体应用及与Mini C终端通信的实现。 相似文献
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A portable acoustic tracking system (PATS) has been developed for the Navy to track underwater construction teams in water depths to 200 ft. The tracking system can be deployed and operated by the divers and is intended for use in remote areas and for nearshore survey, maintenance, and construction work. A self-calibrating system provides a geographically justified track for up to eight divers. Diver position coordinates are computed from acoustic measurements at periodic intervals and displayed for control purposes. The positions are also recorded for future reference. 相似文献
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Underwater acoustic networks 总被引：8，自引：0，他引：8
With the advances in acoustic modem technology that enabled high-rate reliable communications, current research focuses on communication between various remote instruments within a network environment. Underwater acoustic (UWA) networks are generally formed by acoustically connected ocean-bottom sensors, autonomous underwater vehicles, and a surface station, which provides a link to an on-shore control center. While many applications require long-term monitoring of the deployment area, the battery-powered network nodes limit the lifetime of UWA networks. In addition, shallow-water acoustic channel characteristics, such as low available bandwidth, highly varying multipath, and large propagation delays, restrict the efficiency of UWA networks. Within such an environment, designing an UWA network that maximizes throughput and reliability while minimizing the power consumption becomes a very difficult task. The goal of this paper is to survey the existing network technology and its applicability to underwater acoustic channels. In addition, we present a shallow-water acoustic network example and outline some future research directions 相似文献
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The mechanical cable is an essential element in towing operations, remote control of equipment, salvage operations, civil engineering applications, etc.Failure of these cables can result in loss of life and loss of equipment worth hundreds of thousands of dollars. Obviously then, sensors that can indicate the condition of these cables so that the risk to their continued use and their remaining safe life can be determined when in operation are very important from the point of view of commercial and military interest.This paper presents a brief review of research into failure mechanisms of various cables and the acoustic emission signatures of the various cables under simulated loading. The development of a specific operational monitor for a towed cable system is also given. 相似文献
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Erwan Garel Susana Nunes João Magalhães Neto Rodrigo Fernandes Ramiro Neves João Carlos Marques Óscar Ferreira 《Geo-Marine Letters》2009,29(5):331-341
This technical paper describes an autonomous recording system with remote data access for the continuous, long-term in situ
monitoring of water quality and discharge, as well as current velocity. The Simpatico system has been recently deployed in three estuaries in Portugal (Mondego and Tagus in July 2007; Guadiana in March 2008),
highly suitable to illustrate its multifaceted potential applications: surveillance of the effects of mitigation measures
to combat eutrophication (lower Mondego Estuary); real-time implementation of boundary conditions for a water modelling system
(upper Tagus Estuary); study of dam-induced impacts in terms of water quality, water discharge and sediment budgets (mouth
of the Guadiana Estuary). An extract of recorded data serves as an example to discuss data reliability, as well as field maintenance
of the system, with implications for labour and operational costs. The use of a new generation of copper-based anti-biofouling
kits significantly reduced the need for field maintenance operations. Other examples of possible application of the system
include the assessment of gas accumulation in coastal waters. 相似文献
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As drilling operations move into remote locations and extreme water depths, recoil analysis requires more careful considerations and the incidence of emergency disconnect is increased inevitably. To accurately capture the recoil dynamics of a deep-water riser in an emergency disconnect scenario, researchers typically focus on modelling the influential subsystems (e.g., the tensioner, the mud discharge and seawater refilling process) which can be solved in the preprocessing, and then the determined parameters are transmitted into an existing global riser analysis software. Distinctively, the current study devotes efforts into the coupling effects resulting from that the suspended riser reacts the platform heave motion via the tensioner system in the course of recoil and the discharging fluid column follows the oscillation of the riser in the mud discharge process. Four simulation models are established based on lumped mass method employing different formulas for the top boundary condition of the riser and the discharging flow acceleration. It demonstrates that the coupling effects discussed above can significantly affect the recoil behavior during the transition phase from initial disconnect to the final hang-off state. It is recommended to develop a fully- coupled integrated model for recoil analysis and anti-recoil control system design before extreme deep-water applications. 相似文献
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This paper considers the global stability of controlling an uncertain complex network to a homogeneous trajectory of the uncoupled system by a local pinning control strategy. Several sufficient conditions are derived to guarantee the network synchronisation by investigating the relationship among pinning synchronisation, network topology, and coupling strength. Also, some fundamental and yet challenging problems in the pinning control of complex networks are discussed: (1) what nodes should be selected as pinned candidates? (2) How many nodes are needed to be pinned for a fixed coupling strength? Furthermore, an adaptive pinning control scheme is developed. In order to achieve synchronisation of an uncertain complex network, the adaptive tuning strategy of either the coupling strength or the control gain is utilised. As an illustrative example, a network with the Lorenz system as node self-dynamics is simulated to verify the efficacy of theoretical results. 相似文献
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动力定位系统（ＤＰＳ）是开发深海的一种较为有效的海上开发系统。由于ＤＰＳ是一个较为复杂的系统,在进行模型试验时,每个Ｚ型螺旋桨都设有计算机芯片以及遥控装置,用以接收ＰＩＤ系统发出的指令,为模型试验的模拟也带来了一定困难。本文讨论了动力定位系统的数学模型,模型试验中推力的分配及控制方程和试验中的一些要求。 相似文献
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从海洋石油开发实际需求出发,通过分析海上油田安控系统的基本原理及其组成,详细介绍了如何利用M apX控件构建3G(GPS/GIS/GPRS)综合信息处理平台,根据系统流程对海图制作、船舶定位、航行轨迹记录和安控与调度等关键部分进行设计与实现。该系统为海上油田作业及航运提供远程监控、调度和安全控制,确保海上油田施工作业安全,提高航运效率。 相似文献
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提出了一种基于人工免疫网络的遥感图像分类算法。该算法通过借鉴生物免疫网络的分类和泛化能力，训练出能反映训练数据分布特性的网络细胞，然后使用这些网络细胞进行分类。实验结果表明，基于人工免疫网络的遥感图像分类算法具有较好的分类性能，其分类总精度、kappa系数均优于一些传统分类算法。 相似文献
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UML在深海集矿机远程监控系统中应用研究 总被引：3，自引：1，他引：2
分析了UML（unified modeling language）建模方法在信息建模中的优点,具体研究了UML建模方法在深海集矿机远程监控系统建模中的应用;针对深海集矿机远程监控系统的工艺流程,采用UML中的用例图、活动图和序列图等描述远程监控系统的需求、分析和设计阶段的信息系统模型;并对深海集矿机远程监控系统进行建模,使系统模型更通用、更易理解,增强了系统模型的重用性和互操作性。以Rational Rose 2002为工具来描述UML方法的建模过程,开发了深海集矿机远程监控系统,在海洋采矿系统的模型机上试验运行情况良好。 相似文献
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珊瑚礁是海洋生态系统的重要组成部分,对保护海洋生物多样性以及维持海洋生态平衡具有重大意义。我国南海珊瑚岛礁自然资源丰富,准确、高效地提取珊瑚岛礁信息对南海岛礁监测、管理、规划与保护具有现实意义。本研究基于我国海洋一号C卫星（HY 1C）遥感数据,对西沙永乐群岛珊瑚礁信息进行了研究与分析,提出基于HY 1C遥感数据的珊瑚礁地貌分类体系。采用全卷积神经网络U Net模型,依次通过下采样、上采样操作提取西沙永乐环礁地貌特征,实现原始影像的像素级语义分割。结果表明：基于HY 1C数据建立的地貌分类体系对活珊瑚覆盖及珊瑚生长发育条件具有指示作用,提出的基于U Net模型的珊瑚岛礁地貌信息自动提取方法,能够为我国南海珊瑚岛礁生态系统的全自动、大范围监测和评价提供相应理论基础,在珊瑚礁生态管理与评价中发挥关键作用。精度验证结果表明：U Net模型可以有效提取珊瑚礁地貌信息,采用的地貌信息提取方法具备时空泛化能力,泛化精度高于80%。 相似文献
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Accessible high-quality observation datasets and proper modeling process are critically required to accurately predict sea level rise in coastal areas. This study focuses on developing and validating a combined least squares-neural network approach applicable to the short-term prediction of sea level variations in the Yellow Sea, where the periodic terms and linear trend of sea level change are fitted and extrapolated using the least squares model, while the prediction of the residual terms is performed by several different types of artificial neural networks. The input and output data used are the sea level anomalies (SLA) time series in the Yellow Sea from 1993 to 2016 derived from ERS-1/2, Topex/Poseidon, Jason-1/2, and Envisat satellite altimetry missions. Tests of different neural network architectures and learning algorithms are performed to assess their applicability for predicting the residuals of SLA time series. Different neural networks satisfactorily provide reliable results and the root mean square errors of the predictions from the proposed combined approach are less than 2?cm and correlation coefficients between the observed and predicted SLA are up to 0.87. Results prove the reliability of the combined least squares-neural network approach on the short-term prediction of sea level variability close to the coast. 相似文献