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71.
由于近岸视频监测技术具有构建成本低、时空分辨率高的特点,近年来已成为海岸动态监测的互补手段。在近岸视频监测中,水边线可作为岸滩边缘位置变化的替代指标,受复杂海滩地形及不规则的波浪及潮汐变化影响,如何从视频图像中准确检测水边线是近岸视频监测所面临的挑战问题之一。本文针对传统图像处理方法在水边线提取中存在的效率不高和抗噪声能力差等问题,将CIELab颜色模型和蚁群优化算法相结合,对台风风暴潮期间石老人海滩的水边线进行提取和定量分析,并与传统算法进行对比。对青岛石老人海滩2011年台风期间的实时影像资料分析结果表明,与传统的提取算法相比,本文提出的方法在数字视频影像的水边线监测应用中可靠性高,并具有良好的细节呈现能力和抗边缘噪声能力,适用于弱边缘水边线的提取。分析结果验证了本方法在极端天气条件下对视频影像中水边线动态变化的自动提取可行性,对构建长时序海滩岸线动态变化影像自动分析系统具有较好的应用价值。  相似文献   
72.
Bull sharks Carcharhinus leucas are common along the coast of Reunion Island (South-West Indian Ocean) and were suspected to aggregate in the vicinity of an aquaculture farm in Saint-Paul Bay on the west coast. In order to understand the behaviour and interaction of bull sharks near aquaculture cages at Saint-Paul Bay, we deployed an experimental unbaited stationary video camera. From 175 hours of recording during daylight hours from March to April 2012, eight individual female bull sharks (seven adults and one immature) were identified based on their natural markings. These sharks were resighted between 3 and 45 times. Residency analysis revealed site attachment under the aquaculture cages for at least three individuals over the course of the study. Recorded behaviours included intraspecific social interactions such as synchronised swimming. Social interactions and relatively strong paired associations for two pairs of females suggest some level of sociality among bull sharks around Reunion Island. Overall, our results demonstrate the utility of unbaited video systems to monitor the behaviour of adult coastal sharks.  相似文献   
73.
Abnormally high-priced transactions in urban land speculation bring detrimental effects on economy, environment, and society. Governmental agencies around the world are striving hard to monitor and control land speculation by introducing various policy objectives and tools for an efficient urban development planning. One of the major challenges in controlling land speculation is to quickly identify the spatiotemporal locations of concern (hot spots) by monitoring the spatial clustering pattern changes over time and to alert the appropriate decision-making agencies for timely policy intervention. In this paper, we introduce a framework to rapidly detect the spatiotemporal hot spots of speculative land transactions in near-real-time data by exploiting the prospective monitoring procedures. We applied this method in the city of Hwasung, Republic of Korea, as an empirical illustration and found that the locations Jeongnam, Bongdam, Mado, and Dongtan were identified as hot spots with high, concentrated transaction values. The results indicate that the proposed framework is a capable tool for capturing prospective temporal indicators and pinpointing the localities of land speculation.  相似文献   
74.
毛飞  李建明  金龙  敬颖 《气象科技》2017,45(1):64-67
针对目前天气雷达保障业务需求,开发了新一代天气雷达远程视频监控保障系统。该系统实现了雷达设备的视频监控、远程协助、数据采集、状态监测及报警等主要功能。通过该系统可实现雷达故障的快速发现,同时利用远程协助功能,相关专家可根据故障报警、现场可视图像以及雷达关键部位参数进行故障诊断,制定维修方案,提高雷达保障时效。目前该系统已成功应用到全省4个雷达站,满足了远程故障可视化诊断需求。  相似文献   
75.
76.
In this paper, image processing technique that reduces video images of buoy motion to yield time series of image coordinates of buoy objects will be investigated. The buoy motion images are noisy due to time-varying brightness as well as non-uniform background illumination. The occurrence of boats, wakes, and wind-induced white caps interferes significantly in recognition of buoy objects. Thus, semiautomated procedures consisting of object recognition and image measurement aspects will be conducted. These offer more satisfactory results than a manual process. Spectral analysis shows that the image coordinates of buoy objects represent wave motion well, indicating its usefulness in the analysis of wave characteristics.  相似文献   
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78.
地震观测台站远程测控系统的研制与应用   总被引:1,自引:1,他引:0  
通过远程测控系统,监测无人职守地震观测台站设备的工作状态,室内商业供电状态、室内温湿度的监测,室内安全布防及报警;在区域遥测台网中心发现观测设备出现故障时,可以通过专线网络处理简单的设备故障,应急处理已损坏的辅助设备等。  相似文献   
79.
根据国家能源装备制造、煤矿机器人和煤矿智能化发展等政策要求,结合煤炭设备少人化、智能化发展趋势,针对现有煤矿井下钻机参数显示不全、缺乏有效监测、维修不便等问题,为实现自动化钻机地面远程监测,利用传感测量、软件开发、虚拟现实、网络通信、视频监测等技术研制了一种煤矿用自动化钻机远程监测系统。该远程监测系统包括了钻机主体、机载设备、网络通信部分和远程监测服务器。钻机主体为ZDY4500LFK型煤矿用钻机;机载设备包括了控制器和传感器组,用于实现钻机参数采集;网络通信部分包括了交换机、网关等,实现井下和地面的通信;远程监测服务器实现钻机参数和工况的监测。该系统研制后在鄂尔多斯华兴能源有限责任公司唐家会煤矿进行了现场试验,结果显示,该系统数据传输准确,可实现自动化钻机的地面监测功能,为煤矿钻机的少人化、智能化提供了保障。   相似文献   
80.
This paper examines the use of aerial surveillance activities conducted in the North Sea region of Europe since 1986 to assess trends in levels of oil inputs into the marine environment, both across the whole region and within the waters of the different coastal states. It makes use of data collected under the aegis of the 1969 Bonn Agreement through its Annual Reports on Aerial Surveillance and examines developments in surveillance methods and technology which have led to improvements in the detection of oil spills, even during the hours of darkness. The paper then examines country specific data for the eight North Sea contracting parties to the Agreement to assess trends in oil spills in the region.  相似文献   
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