An evaluation of integrating multisourced sensors for disaster management

Disaster management and in particular disaster response phase are highly time-sensitive and dynamic processes, demanding that real-time information reaches disaster responders prior making critical decisions. During the last decade, disaster management has been widely enabled through utilizing spatial data sourcing and related technologies in the whole process of collection, access, and usage of disaster information. Currently, there are unique challenges that cannot be met without incorporating in situ sensing as an emerging technology for sourcing and managing disaster information. These include (1) high temporal and spatial resolution of information, (2) broad range of disaster data, and (3) automated operations. Incorporating in situ sensing into the disaster management process can potentially address such challenges by providing data that support all of these requirements. Following an examination of current concepts and methods for integrating multisourced sensors, a framework of the requirements for integrating in situ sensors for disaster management, is suggested. Based on this framework and its components, an evaluation of the methods is developed and applied. The results highlight that information integration of multisourced sensors is a major challenge and has not yet adequately addressed for sensor data enablement of disaster management.     

A domain-independent methodology to analyze IoT data streams in real-time. A proof of concept implementation for anomaly detection from environmental data

ABSTRACT

Pushed by the Internet of Things (IoT) paradigm modern sensor networks monitor a wide range of phenomena, in areas such as environmental monitoring, health care, industrial processes, and smart cities. These networks provide a continuous pulse of the almost infinite activities that are happening in the physical space and are thus, key enablers for a Digital Earth Nervous System. Nevertheless, the rapid processing of these sensor data streams still continues to challenge traditional data-handling solutions and new approaches are being requested. We propose a generic answer to this challenge, which has the potential to support any form of distributed real-time analysis. This neutral methodology follows a brokering approach to work with different kinds of data sources and uses web-based standards to achieve interoperability. As a proof of concept, we implemented the methodology to detect anomalies in real-time and applied it to the area of environmental monitoring. The developed system is capable of detecting anomalies, generating notifications, and displaying the recent situation to the user.     

海洋拖曳式水平电偶源数值模拟与电场接收机研制

海洋天然气水合物资源调查中,电磁法已成为地震勘探最有效的补充手段之一,而我国海洋水合物电磁探测中的拖曳式电场接收机此前是空白.本文从方法原理、仪器设备和海洋试验等方面,对海洋拖曳式水平电偶极-偶极方法进行研讨.建立三维电阻率模型,进行数值模拟,讨论收发距、发射频率、拖曳装置离海底高度等参数与电场异常响应的关系,针对特定模型给出了最佳观测参数以指导仪器硬件设计与海洋测试.在此基础上,采用高级嵌入式计算机的智能化控制、前端低噪声斩波放大、高精度同步采集等技术,研制了由拖体、承压舱、采集电路、低噪声电场传感器等组成的海洋拖曳式水平轴向电场接收机,其系统噪声达到2 nV/√HZ @(1~100Hz).将自主研制的电场接收机用于国内首次拖曳式电偶极-偶极方法的海洋试验与评估,并对海试资料进行了处理与分析.研究结果表明,所研发的仪器达到了设计指标,能够用于海洋天然气水合物调查.     

The Kinect: a low‐cost,high‐resolution,short‐range 3D camera

We present a novel application of the Kinect?, an input device designed for the Microsoft® Xbox 360® video game system. The device can be used by Earth scientists as a low‐cost, high‐resolution, short‐range 3D/4D camera imaging system producing data similar to a terrestrial light detection and ranging (LiDAR) sensor. The Kinect contains a structured light emitter, an infrared camera (the combination of these two produce a distance image), a visual wavelength camera, a three‐axis accelerometer, and four microphones. The cost is ~ US $100, frame rate is 30 Hz, spatial and depth resolutions are mm to cm depending on range, and the optimal operating range is 0.5 to ~5 m. The resolution of the distance measurements decreases with distance and is ≤1 mm at 0.5 m and ~75 mm at 5 m. We illustrate data collection and basic data analysis routines in three experiments designed to demonstrate the breadth and utility of this new sensor in domains of glaciology, stream bathymetry, and geomorphology, although the device is applicable to a number of other Earth science fields. Copyright © 2012 John Wiley & Sons, Ltd.     

Relationship between bedload and suspended sediment in the sand-bed Exu River,in the semi-arid region of Brazil

Abstract

Suspended sediment and bedload discharges in sand-bed rivers shape semi-arid landscapes and impact sediment delivery from these landscapes, but are still incompletely understood. Suspended sediment and bedload fluxes of the intermittent Exu River, Brazil, were sampled by direct measurements. The highest suspended sediment concentration observed was 4847.4 mg L^-1 and this value was possibly associated with the entrainment of sediment that was deposited in the preceding year. The bedload flux was well related to the stream power and the river efficiently transported all available bedload with a mean rate of 0.0047 kg m^-1 s^-1, and the percentage of bedload to suspended sediment varied between 4 and 12.72. The bed sediment of Exu River was prone to entrainment and showed a proclivity for transport. Thus, sand-bed and gravel-bed rivers of arid environments seem to exhibit the same mobility in the absence of armour layer.

Editor D. Koutsoyiannis; Associate editor B. Touaibia

Citation Cantalice, J.R.B., Cunha Filho, M., Stosic, B.D., Piscoya, V.C., Guerra, S.M.S., and Singh, V.P., 2013. Relationship between bedload and suspended sediment in the sand-bed Exu River, in the semi-arid region of Brazil. Hydrological Sciences Journal, 58 (8), 1789–1802.     

GPＲ 探测电力工程地埋管线的技术方法

在电力工程地埋管线探测中,GPＲ 是一种行之有效的方法。为提高管线探测的精度,降低工程施工风险,笔者从探地雷达野外数据采集开始,详细探讨了探地雷达应用于管线探测时的数据采集方法 ( 包括测线的布设、干扰因素的避让等) 和室内后续数据处理的策略。针对管线探测这一目标,采用预测反褶积技术压制多次波和非线性颜色分级的剖面显示方式是提高数据解释精度的关键,并结合电力隧道地下管线探测实例验证了本文所提方法的有效性。     

流变应力恢复法地应力测试及装置

深部软岩体应力测试难度大,尚无有效测试技术。对此,研制了一种适用于软岩体应力测试的三向压应力传感器,提出了相应的解算方法,并对传感器进行了标定试验、干扰试验和室内模型试验。标定试验结果表明,传感器的线性度、重复性等静态性能良好。当荷载不断增大时,传感器的测量误差先逐渐减小,直至为0,而后又逐渐增大,但误差基本上都在10%以内,说明传感器能较精确地测量量程范围内的应力大小。干扰试验结果表明,传感器3个传感面之间的相互干扰可以忽略不计。模型试验结果表明,随着加载次数的增加,传感器所感知的力越来越接近所施加的力,最后趋近于相等,进一步表明了该传感器基本满足工程实践要求。此外,初步探讨了传感器的优化设计方向等问题。     

一种基于机载激光点云的门型电塔精确提取方法

随着无人机技术的发展,越来越多的电力部门采用机载激光雷达及倾斜摄影测量技术代替传统的人工方法,进行电力巡检、电力部件检修等工作。门型电塔为目前电力走廊中比较常见的一种高压电塔。在无数据标签的电网点云数据中,对门型电塔进行精确点云提取是门型电塔日常维护的重要工作。本文从包含有地面、植被、电力线、门型电塔的电网点云数据入手,首先对点云进行体素化分割,对体素网格进行高程连续与高程阈值的筛选,并对电塔顶部进行扩展搜索,达到去除地面点及植被点的目的。然后根据门型电塔水平投影成条状的特点,利用门型电塔的圆柱杆塔部分得到门型电塔的水平投影直线,再通过距离阈值判断去除点云中多余的电力线点。本文介绍的方法实现了从无标签的电网点云数据中对门型电塔的精确提取,为进一步进行门型电塔的三维建模、维护检修等工作提供了数据基础。     

Distribution characteristics of wave energy in the Zhe-Min coastal area

A 10-year（2003–2012） hindcast was conducted to study the wave field in the Zhe-Min coastal area（Key Area OE-W2） located off Zhejiang and Fujian provinces of China. Forced by the wind field from a weather research and forecasting model（WRF）, high-resolution wave modelling using the SWAN was carried out in the study area. The simulated wave fields show a good agreement with observations. Using the simulation results, we conducted statistical analysis of wave power density in terms of spatial distr...     

基于模型试验的海洋核动力平台定位系统解脱作业关键指标分析

海洋核动力平台定位系统采用软刚臂单点系泊方式,属于多铰连接的单点系泊装置。定位系统在长期海上运营过程中,会面临结构维护、改造、更换等作业,解脱作业的安全性是定位系统乃至核动力平台安全的重要组成。借鉴国内外海洋石油平台解脱作业的成功案例,首先给出了核动力平台定位系统解脱作业的流程,并结合解脱作业故障树的风险传递路径给出关键风险指标;然后基于相似理论搭建了定位系统1∶9缩尺比模型试验平台,真实模拟了定位系统全流程解脱作业,验证了定位系统解脱作业的可行性与有效性;基于实时测量数据分析提升缆绳在限位状态与解脱作业时的张力响应、法兰解脱时系泊腿下部万向节振动响应、系泊刚臂下放姿态等关键指标。研究结果表明物理试验模拟方法可以准确表征解脱作业过程的关键节点,并为量化作业指标、优化作业流程提供数据支持,同时相关试验分析方法可以为其他海洋装备的解脱、安装等提供参考。