黄海绿潮灾害应急遥感监测和预测预警系统

黄海绿潮灾害应急遥感监测和预测预警系统是在绿潮应急遥感监测技术、应急快速漂移预测等技术研究的基础上,基于GIS技术构建了集绿潮遥感信息解译和提取、多源监测数据融合、快速漂移预测和预警产品制作和发布综合业务化平台。在应急遥感监测数据提取方面主要研发了信息提取准自动化技术和多源多时间窗的绿潮监测数据融合技术;在应急预测技术方面主要基于精细化大气和海洋环境动力场,研发了绿潮快速应急漂移预测模型,并通过海上和后报实验提高模拟精度。本系统服务于国家海洋局和政府防灾减灾应急部门,为海上运动、水产养殖、滨海旅游、交通运输、渔业生产等涉海活动和海洋管理提供了科学可靠的技术保障,特别在2008年奥运会帆船/板赛和2012年亚洲沙滩运动会的绿潮监测和预测预警保障工作中发挥了重要的作用,具有巨大的社会、经济和生态效益。     

粤北某矿横石河流域周围土壤重金属预测与生态风险预警评估

以粤北某矿横石河流域周围表层土壤2010年和2013年两批区域调查数据为基础,对其土壤中重金属含量变化趋势进行预测,并进行生态风险预警评估。结果显示,3年间土壤中Cd、Cu、Pb、Zn等元素含量降低明显,现累积速率分别为-0.001、2.88、3.71和3.11mg/(kg·a),相对累积速率以Cd最快,Zn、Cu、Pb次之;生态风险预警评估显示凉桥村和水楼下村的生态风险达到重警,上坝村为轻警。在无突变情景下,根据现累积速率预测了未来30年内的生态环境质量变化,并提出建议。     

儿童对不同形状字体警示语标识的眼动特征

为研究儿童对不同形状字体警示语标识的视觉注意特征,将字体形状为单一变量的警示语标识图片作为视觉刺激材料,利用Eye-Link Ⅱ型眼动仪记录了30名小学生观看这些图片时的注视点个数和首次注视时间等试验数据,用SPSS分析了注视点个数和首次注视时间,基于视觉注意理论结合主观调查问卷结果表明:1)被试者对黑体字体注意程度最大;2)儿童对不同形状字体警示语标识的注意程度由大到小为黑体、隶书、宋体(楷体)、幼圆.     

Driver Behavior During Overtaking Maneuvers from the 100-Car Naturalistic Driving Study

Objective: Lane changes with the intention to overtake the vehicle in front are especially challenging scenarios for forward collision warning (FCW) designs. These overtaking maneuvers can occur at high relative vehicle speeds and often involve no brake and/or turn signal application. Therefore, overtaking presents the potential of erroneously triggering the FCW. A better understanding of driver behavior during lane change events can improve designs of this human–machine interface and increase driver acceptance of FCW. The objective of this study was to aid FCW design by characterizing driver behavior during lane change events using naturalistic driving study data.

Methods: The analysis was based on data from the 100-Car Naturalistic Driving Study, collected by the Virginia Tech Transportation Institute. The 100-Car study contains approximately 1.2 million vehicle miles of driving and 43,000 h of data collected from 108 primary drivers. In order to identify overtaking maneuvers from a large sample of driving data, an algorithm to automatically identify overtaking events was developed. The lead vehicle and minimum time to collision (TTC) at the start of lane change events was identified using radar processing techniques developed in a previous study. The lane change identification algorithm was validated against video analysis, which manually identified 1,425 lane change events from approximately 126 full trips.

Results: Forty-five drivers with valid time series data were selected from the 100-Car study. From the sample of drivers, our algorithm identified 326,238 lane change events. A total of 90,639 lane change events were found to involve a closing lead vehicle. Lane change events were evenly distributed between left side and right side lane changes. The characterization of lane change frequency and minimum TTC was divided into 10 mph speed bins for vehicle travel speeds between 10 and 90 mph. For all lane change events with a closing lead vehicle, the results showed that drivers change lanes most frequently in the 40–50 mph speed range. Minimum TTC was found to increase with travel speed. The variability in minimum TTC between drivers also increased with travel speed.

Conclusions: This study developed and validated an algorithm to detect lane change events in the 100-Car Naturalistic Driving Study and characterized lane change events in the database. The characterization of driver behavior in lane change events showed that driver lane change frequency and minimum TTC vary with travel speed. The characterization of overtaking maneuvers from this study will aid in improving the overall effectiveness of FCW systems by providing active safety system designers with further understanding of driver action in overtaking maneuvers, thereby increasing system warning accuracy, reducing erroneous warnings, and improving driver acceptance.     

基于物联网技术的化工园区环境应急预警系统研究

为及时有效应对化工园区内各种突发性环境污染事故,采用物联网技术构建化工园区环境应急预警系统,主要包括重点区域太阳能无线自持子系统、远红外气体及火灾智能监测子系统、开路紫外差分吸声光谱气体监测子系统、管网次声波监测子系统和仪器、试剂及样品管理子系统5个子系统。该系统的运行可对整个园区及其周边的环境质量进行有效监控,预防和及时控制各种环境污染事故的发生,同时为园区管理部门提供数据和信息支持。     

数据缺失条件下基于MLP神经网络的水华风险预警方法研究

针对水华风险预警过程中相关监测指标数据缺失的问题,借鉴多元统计和随机分析构建了一种缺失数据插补方法,用于弥补现场调查数据的不足.基于主成分分析,对水华相关影响指标进行降维,确定水体水华风险预警模型的输入层变量.同时,采用多层感知器(MLP)人工神经网络模型对水华表征指标叶绿素a的浓度进行预测,并引入风险概率的概念,提出了水华风险概率计算公式,完善了水华预警的风险表达.最后以三峡库区典型支流大宁河为案例的研究证明了上述方法的可操作性.研究结果显示,插补数据条件下和未插补数据条件下的大宁河水华风险预警模型决定系数分别为0.9711和0.7769,前者的模型准确性更高,叶绿素a浓度预测效果更好;预测时段内大宁河11 d为水华蓝色预警(无警)级别,水华发生的风险概率为1.99%~18.61%;1 d达到水华橙色预警(中警)级别,水华发生概率为90.48%.     

长输油气管线安全生产事故监测预警平台设计与实现

阐述了适用于长输油气管线安全生产事故应急救援全过程的事故监测预警平台的整体结构和实现要点,主要从长输油气管线的工作运行和事故特点出发,结合安全生产事故应急救援过程中各环节的业务需求,提出监测预警平台的建设目标和适用范围,对平台的需求进行分析,并进一步对平台的构建思路进行讨论。其中重点从应急预防、应急准备、应急响应和应急恢复四个阶段的应急任务和需求入手,提炼出长输油气管线安全生产事故监测预警平台在＂后端应急指挥中心＂、＂现场应急指挥中心＂及＂移动指挥所＂等多个位置和场景下的建设目标和功能框架,并对平台设计与实现过程中可能涉及到的平台总体结构设计、平台软硬件及网络支撑环境、平台数据采集传输与共享模式等方面进行了简要描述。     

Multivariate Analysis of Motorcycle Accidents and the Effects of Exclusive Motorcycle Lanes in Malaysia

This paper presents a multivariate analysis on the impact of the exclusive motorcycle lane on motorcycle accidents along the Federal Highway Route 2, Malaysia. A number of statistical models have been developed to explain the relationship of motorcycle accidents and explanatory variables relevant to motorcycle safety. The best model showed that motorcycle accidents are directly proportional to the cubic power of traffic flow and reduced by approximately 39% with the motorcycle lane. A clear benefit of this lane is observed when the traffic flow exceeds 15,000 vehicles per day per lane for motorcycle proportion of between 20% and 30%. Besides supporting the notion for motorcycle segregation, this finding provides an initial guideline on the warrants for an exclusive motorcycle lane for highly motorcycled countries in Asia.     

基于警源-压力-预警能力的城市公共危机预警研究

为提高城市公共危机系统预警能力,基于耶克斯-多德森(Yerkes-Dodson)定律构建该系统警源-压力-预警能力的概念模型,分析警源、压力、预警能力三者间的关系,进而提出警源-压力-预警能力的系统动力学(SD)模型,并利用Vensim PLE仿真软件进行案例模拟分析,最后结合仿真结果从系统内外2个维度探讨提高城市公共危机系统预警能力的应对策略。结果表明:警源和压力是城市公共危机系统预警能力的2个主要影响因素。建立健全相关法律体系和改善危机系统"周边环境",减小外部警源到达率;完善预警机制和加强防范管理,提高系统内部鲁棒性,能够提高城市公共危机系统预警能力。     

闽南地区农村征地冲突的风险预警及防范对策--以福建省晋江市为例

借鉴社会冲突理论构建了农村征地冲突风险预警指标体系,并以闽南地区晋江市为案例区,运用模糊综合评价法分析了农村征地冲突风险警级水平及其产生机制。结果表明:闽南地区农村征地冲突风险水平整体处于中警级别,农村征地冲突风险警级水平与该区域的特征密切相关。基于研究结果,为有效防范闽南地区农村征地冲突风险,应从完善征地纠纷矛盾调解机制、尊重农户心理需求和文化认同、建立分级控制预警机制等方面制定风险防范对策。