Risk assessment of chemical process considering dynamic probability of near misses based on Bayesian theory and event tree analysis

With the development of modern automatic control systems, chemical accidents are of low frequency in most chemical plants, but once an accident happens, it often causes serious consequences. Near-misses are the precursor of accidents. As the process progresses, near misses caused by abnormal fluctuation of process variables may eventually lead to accidents. However, variables that may lead to serious consequences in the production process cannot update the risk in the life cycle of the process by traditional risk assessment methods, which do not pay enough attention to the near misses. Therefore, this paper proposed a new method based on Bayesian theory to dynamically update the probability of key variables associated with process failure risk and obtain the risk change of the near-misses. This article outlines the proposed approach and uses a chemical process of styrene production to demonstrate the application. In this chemical process, the key variables include flow rate, liquid level, pressure and temperature. In order to study the dynamic risk of the chemical process with consideration of near misses, according to the accumulated data of process variables, firstly the abnormal probability of the variables and the failure rate of safety systems associated with the variables were updated with time based on Bayesian theory. On the basis of the dynamic probability of key process variables, an event tree of possible consequences caused by variable anomalies was established. From the logical relationship of the event tree, the probability of different consequences can be obtained. The results show that the proposed risk assessment method based on Bayesian theory can overcome the shortcomings of traditional analysis methods. It shows the dynamic characteristics of the probability of different near misses, and achieves the dynamic risk analysis of chemical process accidents.     

When work is wanted after hours: Testing weekly stress of information communication technology demands using boundary theory

Information communication technologies (ICTs; e.g., smartphones) enable employees to work anywhere and anytime, blurring work and family boundaries. Building on this trend, this study draws from work–family border/boundary theory to examine antecedents and consequences of employees' weekly experiences of ICT demands (i.e., being accessible and contacted for work after hours via ICTs). A sample of 546 elementary teachers completed a registration survey and a weekly diary for 5 weeks. Multilevel modeling results suggest that ICT demands as a form of work intrusion in the home can constitute a source of significant weekly strain (i.e., negative rumination, negative affect, and insomnia). As border crossers, teachers' adoption of a technological boundary tactic (i.e., keeping work email alerts turned off on mobile phones) was related to lower weekly ICT demands. As important border keepers at work, school principals' work–family support was related to teachers' lower weekly ICT demands, whereas parents' after-hours boundary expectations were related to teachers' higher weekly ICT demands. Moreover, teachers' boundary control was found as a mediating mechanism by which the two border keepers influenced teachers' ICT demands−negative rumination link. That is, teachers who received fewer boundary expectations and/or more work–family support had greater boundary control, which in turn buffered the ICT demands–negative rumination relationship.     

基于轴—辐理论的皖江城市带物流网络空间构建

大力发展现代物流业和皖江城市带承接产业转移示范区建设是两大重要国家级战略.首先对轴—辐理论的国内外研究现状进行了总结和归纳,分析了轴—辐网络的结构及其优劣势.其次,设计了物流中心性指数的评价指标体系,运用主成分分析法对皖江城市带的9个地级城市进行物流节点等级划分,根据分析结果的总得分和区位特征确定合肥、芜湖、安庆3个一级物流节点,形成轴三角.分析了各级物流节点间的干线及支线物流通道,构建了皖江城市带轴—辐物流网络空间.     

生物法废气净化专用微生物菌种及其作用

用气相培育驯化法培养获得废气净化专用菌种,由其挂膜制作的生物膜填料塔对废气中甲苯进行净化,实验结果表明,气相培养法所得菌种对甲苯的净化性能明显优于液相培养法所得菌种.生物膜通过吸附-生物降解作用过程净化气相中的甲苯,使针对挥发性有机废气生物净化过程提出的吸附-生物膜动力学理论的依据得到了验证.     

西部大开发中的生态安全问题

正确处理区域发展与生态安全是西部开发战略的关键。以可持续发展为目标的区域空间结构理论 ,分析了在新一轮科技革命和产业革命的新形势下推动区域发展和区域空间结构演变的决定性因素 ,以及实行效益原则与社会公平原则相统一的必要性 ,从中引出西部大开发中确保生态安全的极端重要性。并就实现区域发展与生态安全的双赢目标所必须建立的能力体系和制度体系提出了建议。      

生态工业园区水资源梯级利用的博弈分析

水资源是生态工业园区中最重要的资源之一,模拟自然生态系统,园区中的水资源用户也可根据功能的不同分为生产者、消费者和分解者.由于供给量的限制和国家的排污政策逐渐趋紧,生态工业园区中水资源数量和质量的分配存在利益冲突的问题,矛盾日渐凸现.本文试图运用博弈论的方法,构建一个水资源管理的梯级利用模式,探讨生态工业园区内水质要求不同的企业间如何实现水资源的合理分配,使之既符合企业的需要,又符合整个园区的供给限制,同时对环境的损害最小.之后从微观经济学的角度对各利益主体参与水资源梯级利用的动因和积极性进行了经济学上的分析,得出生态工业园区中水资源梯级利用体系能否达成“物尽其用、废物最小化”的目标,取决于不同利益者的博弈结果.水资源价格和排污收费价格的提高,可以减少新鲜水资源的购买量和最终的排污量,有利于促进园区内企业间的水资源梯级利用；而梯级利用的过程,也是各级消费者之间的一场博弈,博弈结果将决定再生水资源的售出价格.     

Controversial sectors in banks’ sustainability reporting

Albeit indirectly, through its lending and investing, the financial sector can contribute substantially to achieve sustainable development. One of such practices concerns investment on or financing of entities that deal with environmentally or socially sensitive transactions (gambling, tobacco, alcohol, arms, etc.). Although there is a wealth of literature on banks’ CSR and its reporting, one can count on the fingers of one hand the studies mentioning explicitly these issue. What is more, this CSR practice gets treated only cursorily in these few studies. This study focuses on the communication of information on investment and financing of firms from controversial sectors in banks’ sustainability reports. We begin by examining whether financial institutions in our sample report having such policies or not. Then, we investigate what kind of policies are reported. In addition, this study seeks to capture the influence of national culture and firm-specific characteristics (type of property, listing status and multinationality) on the reporting of such issues. Ordinal regression analysis is used to analyse the relation of these factors with such reporting. Our findings suggest that the disclosure of information on policies regarding investment on and financing of firms from controversial sectors is not widespread, and the organizations reporting policies of total exclusion of some sectors or projects on ethical grounds are few. This study may encourage more detailed analyses of the type of CSR policies examined and of their impacts. It also may be of utility to banks by raising awareness about the need to consider these issues.     

Optimal Marking of Threatened Species to Balance Benefits of Information with Impacts of Marking

Abstract: Marking animals so that they are uniquely identifiable provides information that may assist conservation efforts. Nevertheless, some methods used to mark animals can be harmful. We used mathematical methods to assess the trade‐off between the impact of marking threatened species and the value of the information gained. We considered the case where 2 management strategies, each aiming to improve a species' survival rate, are implemented in an experimental phase. The results of the experiment were applied in a postexperimental management phase. We expressed the expected number of survivors in both phases mathematically, accounting for any mortality caused by the experiment, and determined the proportion of animals to mark to maximize this number. The optimal number of animals to mark increased with the number of individuals available for the experiment and with the number of individuals to be managed in the future. The optimal solution was to mark only 25% of the animals when there were 1000 individuals available for the experiment, the results were used to manage 2000 individuals, and marking caused mortality of 1%. Fewer animals were marked when there were fewer animals in either phase or when marking caused higher mortality. In the case of the Helmeted Honeyeater (Lichenostomus melanops cassidix), the optimal proportion to mark was <1 if the mortality rate was >0.15%–1%, with the threshold depending on the number of animals in the experimental and postexperimental phases. The trade‐off between gaining more information about a species and possibly harming individuals of that species by marking them is difficult to assess subjectively. We show how to determine objectively the optimal proportion of animals to mark to enhance the management of threatened species.     

道路危险货物运输企业安全性评价研究

在分析道路危险货物运输企业安全性评价特点的基础上,结合相关评价指标体系,引入李克特量表法构建安全性评价量表,并基于物元分析理论进行道路危险货物运输企业安全性评价。最后对四川省5家道路危险货物运输企业进行实例分析,结果表明,该评价模型较传统评价方法可更准确地给出安全性等级评价结果,并能够较完整地反映企业安全管理的综合水平。     

基于博弈论的安全决策信息融合

安全信息融合的研究涉及多源信息的表示、内在联系和运动规律的研究。冗余和互补的多源信息在融合系统中不可避免地存在着相互竞争和协同作用,因而多源融合系统中的信息冲突与合作的分析成为信息融合理论研究中的核心与实质问题。博弈理论对冲突和合作局势分析与研究提供了一种定量工具,其研究成果成功地解释了多局中人在“交互决策”过程如何构造博弈的“均衡点”,以及“均衡点”所具有的各种特性。笔者在研究了博弈理论的基础上,以博弈论的观点和方法解决安全信息融合系统冲突信息环境下的融合系统决策问题,并建立了相应的模型并应用了融合算法。