Risk assessment of rare events

Rare events often result in large impacts and are hard to predict. Risk analysis of such events is a challenging task because there are few directly relevant data to form a basis for probabilistic risk assessment. Due to the scarcity of data, the probability estimation of a rare event often uses precursor data. Precursor-based methods have been widely used in probability estimation of rare events. However, few attempts have been made to estimate consequences of rare events using their precursors. This paper proposes a holistic precursor-based risk assessment framework for rare events. The Hierarchical Bayesian Approach (HBA) using hyper-priors to represent prior parameters is applied to probability estimation in the proposed framework. Accident precursor data are utilized from an information theory perspective to seek the most informative precursor upon which the consequence of a rare event is estimated. Combining the estimated probability and consequence gives a reasonable assessment of risk. The assessed risk is updated as new information becomes available to produce a dynamic risk profile. The applicability of the methodology is tested through a case study of an offshore blowout accident. The proposed framework provides a rational way to develop the dynamic risk profile of a rare event for its prevention and control.     

基于模糊信息熵的流域水污染系统建模与控制

我国水污染局部得到了改善,但呈现流域污染蔓延的趋势。运用系统控制论构建流域水污染控制系统,突破了传统的"就水论水、见污治污"的还原论水污染控制方法,综合考虑总体控制战略决策(S)反馈系统以及社会发展布局(L)、经济发展模式(E)、居民生活方式(C)和治理工程措施(T)控制系统等多种控制措施及因素,通过输出量与参考给定输入的比较,采用模糊信息熵方法进行了定量分析方法的探讨。     

考虑人口老龄化的地铁安全疏散仿真研究

为研究老龄化程度对地铁安全疏散的影响,基于人口统计学数据,运用多智能体仿真方法模拟2050年人口老龄化情况下徐州市某地铁站乘客疏散情况,并通过视觉智能识别方法验证仿真模型对地铁乘客疏散描述的准确性。研究结果表明:老龄化比例增加一定程度上会使疏散时间增加,老龄化比例对总体疏散时间的影响程度与疏散总人数有关,疏散总人数越低,随着老龄化比例的增加整体疏散时间显著增加。     

Risk information in decision-making: definitions,requirements and various functions

Inappropriate decisions are often regarded as causes of major accidents in the process industries. To improve the quality of decisions, it is important to make the right information available at the right time. The objective of this work is to investigate what types of risk information is needed for risk-related decisions in various decision-making processes. A framework is proposed to facilitate future research for easing information deficiency. In this paper, risk information is examined through common decision-making processes, and is identified serving to 1) detect and characterize risk-related decision problems, 2) indicate the severity and urgency of decisions, 3) state requirements and constraints of workable solutions, 4) represent attributes for comparing and evaluating solutions, and 5) act as rules to maintain safety or control risk. These usages of risk information in different decision problems imply the large diversity in information needs for decision-making. An adaptive information support is thus suggested to provide targeted risk information to specific decision-makers for effective and efficient decision-making in accident prevention in the process industries.     

基于WEBGIS的城市建筑物震害评估方法研究

城市是人口高度密集且财富集中的地区,一旦发生地震,城市遭受的破坏和打击是巨大的。由于地震造成损失的主要原因是建筑物的倒塌及破坏,因此通过开发基于WEBGIS的城市建筑物震害预测信息系统,对城市建筑物震害的损失估计有着十分重大的意义。利用WEBGIS网络化空间分析技术,结合城市区域特征分区易损性模型,同时采用综合系数评价方法,对震时城市内的钢混、砖混、砖木、石砌、土木等五类结构进行了易损性计算,最后得出了各类建筑物破坏的严重程度以及由此造成的损失,为震后应急指挥管理提供了指导意见。最后结合在福建省地震局地震灾情快速评估系统中的实际应用,说明该方法的实用性和有效性。     

Resetting relationship trajectories: A reconceptualization of the relationship repair process

Negative events within and outside of work can disrupt coworkers' relationships, triggering a re-evaluation of relationship quality. The subjective experience of these events – which we term relationship threats – harms relationships, resulting in long-lasting negative interpersonal and organizational consequences. Coworkers' responses to a relationship threat determine whether relationships are repaired or whether the threat leads to a loss of commitment, lowered satisfaction, and increased negative affect. Because of the critical role that relationships play in organizational life, it is vital that we have a comprehensive understanding of the repair process. To date, researchers have focused on one of three repair processes: trust repair. In reconceptualizing relationship repair, we flesh out the remaining two processes: relationship work and sensemaking. Our reconceptualization balances the restorative actions that mitigate in-the-moment harm with those that sustain these benefits over time. We expand our understanding of relationship repair by highlighting the role that narrative foundations play in determining a relationships' vulnerabilities and determining effective repair processes. We highlight the importance of considering relationship threats as events embedded within a relationship's history; identify narrative foundations as a bridging mechanism between disrupted relationships and their repair; and expand our conceptualization of the processes that repair relationships.     

基于信息扩散理论的火灾风险评估模型研究及其应用

城市火灾事故不断发生,严重威胁着人们的生命安全。当火灾样本数目较少时,针对传统统计模型难以胜任的特点,引入了信息扩散理论,给出了火灾风险评估的实用模型,并以某市为例进行火灾风险评估。结果表明,该方法简单易行,分析结果意义清楚,具有一定的现实意义,为防火抗灾提供了依据。     

灾害应急网络系统中的风险信息传递与沟通

为了探讨灾害的风险传递规律及其风险传递的阻断措施,基于系统理论和信息论的原理,将灾害应急管理体系视为一个复杂的系统,讨论灾害风险传递系统中要素的关联性和信息感知的非线性特性可能产生风险的传递性。结果表明,风险的传递性主要存在于信息缺乏和应急知识的不成熟的灾害应急网络体系中,并且可以将风险传递结构关系分成关系型、层次型、树形和网状型4种类型。最后,利用信息熵的方法表述信息在传递中的损失,指出风险沟通可以阻断风险传递链。     

面向危险化学品运输监测系统的信息融合模型构建

设计一种可用于危化品运输全过程安全状态实时监测的多参数监测系统,并以该系统为基础,构建面向危化品运输安全监测系统的多传感器信息融合模型。该模型综合利用系统监测到的多种参数信息,通过数据预处理、特征提取和状态判决、形势判决、危险态势估计和预测等4个级别的信息融合,结合危险报警模块和数据库管理系统,自动分析被测数据,最终达到对危化品运输安全分类、分级、分层次报警的目的。以该模型为基础讨论部分信息融合算法并设计相应的软件,在实际构建的针对液化石油气的危化品安全监测系统中进行应用试验,结果说明了信息融合模型的有效性。     

林业信息化建设与林业生态文明的战略关系研究

信息化可以为林业经济发展节约资金,实现资源共享,带来显著的社会、生态和经济效益。生态文明作为现代林业建设的战略目标,必须采用当前各种新技术来促进和实现。本文特色是紧扣生态文明这一当前流行主题,研究信息化技术在现代生态林业建设过程中的作用、手段、评价标准和互动关系等。