Building a Human Health Risk Assessment Ontology (RsO): A Proposed Framework

Over the last decade the health and environmental research communities have made significant progress in collecting and improving access to genomic, toxicology, exposure, health, and disease data useful to health risk assessment. One of the barriers to applying these growing volumes of information in fields such as risk assessment is the lack of informatics tools to organize, curate, and evaluate thousands of journal publications and hundreds of databases to provide new insights on relationships among exposure, hazard, and disease burden. Many fields are developing ontologies as a way of organizing and analyzing large amounts of complex information from multiple scientific disciplines. Ontologies include a vocabulary of terms and concepts with defined logical relationships to each other. Building from the recently published exposure ontology and other relevant health and environmental ontologies, this article proposes an ontology for health risk assessment (RsO) that provides a structural framework for organizing risk assessment information and methods. The RsO is anchored by eight major concepts that were either identified by exploratory curations of the risk literature or the exposure‐ontology working group as key for describing the risk assessment domain. These concepts are: (1) stressor, (2) receptor, (3) outcome, (4) exposure event, (5) dose‐response approach, (6) dose‐response metric, (7) uncertainty, and (8) measure of risk. We illustrate the utility of these concepts for the RsO with example curations of published risk assessments for ionizing radiation, arsenic in drinking water, and persistent pollutants in salmon.     

A Flexible Hierarchical Bayesian Modeling Technique for Risk Analysis of Major Accidents

Safety analysis of rare events with potentially catastrophic consequences is challenged by data scarcity and uncertainty. Traditional causation‐based approaches, such as fault tree and event tree (used to model rare event), suffer from a number of weaknesses. These include the static structure of the event causation, lack of event occurrence data, and need for reliable prior information. In this study, a new hierarchical Bayesian modeling based technique is proposed to overcome these drawbacks. The proposed technique can be used as a flexible technique for risk analysis of major accidents. It enables both forward and backward analysis in quantitative reasoning and the treatment of interdependence among the model parameters. Source‐to‐source variability in data sources is also taken into account through a robust probabilistic safety analysis. The applicability of the proposed technique has been demonstrated through a case study in marine and offshore industry.     

Risk to Groundlings of Death Due to Airplane Accidents: A Risk Communication Tool

During the period 1975-85 in the United States the 70 year lifetime risk of dying from being hit by an airplane when the individual is on the ground was 4.2 per million people. In contrast to many other risks used for comparison purposes, risk to those on the ground from an airplane crash is not a function of our own skills; is not optional; provides no benefit to anyone involved; and is not an act of nature. As a risk comparison tool it also has the useful characteristics of being something about which we can agree that regulatory action, such as control of airplane use and traffic, is warranted; but that no significant change in personal behavior, such as living in the basement to protect against dying from a plane hitting the home, is commensurate with the extent of risk.     

基于UML扩展机制的本体模型的可视化研究

首先给出本体的基本模型,并介绍了基于RDF的本体描述语言--DAML,然后比较UML与DAML之间的相似性与不同之处,并指出利用UML表示本体模型的关键问题所在,分析Baclawski等人UML扩展模型的不足,最后提出一种新的UML元模型的扩展模型.     

Risk Assessment Based on Financial Data: Market Response to Airline Accidents

The risk of catastrophic failures, for example in the aviation and aerospace industries, can be approached from different angles (e.g., statistics when they exist, or a detailed probabilistic analysis of the system). Each new accident carries information that has already been included in the experience base or constitutes new evidence that can be used to update a previous assessment of the risk. In this paper, we take a different approach and consider the risk and the updating from the investor's point of view. Based on the market response to past airplane accidents, we examine which ones have created a surprise response and which ones are considered part of the risk of the airline business as previously assessed. To do so, we quantify the magnitude and the timing of the observed market response to catastrophic accidents, and we compare it to an estimate of the response that would be expected based on the true actual cost of the accident including direct and indirect costs (full-cost information response). First, we develop a method based on stock market data to measure the actual market response to an accident and we construct an estimate of the full-cost information response to such an event. We then compare the two figures for the immediate and the long-term response of the market for the affected firm, as well as for the whole industry group to which the firm belongs. As an illustration, we analyze a sample of ten fatal accidents experienced by major US domestic airlines during the last seven years. In four cases, we observed an abnormal market response. In these instances, it seems that the shareholders may have updated their estimates of the probability of a future accident in the affected airlines or more generally of the firm's future business prospects. This market reaction is not always easy to explain much less to anticipate, a fact which management should bear in mind when planning a firm's response to such an event.     

基于差分进化自动聚类的信用风险评价模型研究

随着风险评价的日益复杂化, 多维度、多时序等不规则的样本数据增加了评估的难度。本文建立信用风险评价的差分进化自动聚类模型, 并将其应用到我国上市公司信用风险评价中。该模型不要求事先知道分类的数据, 相反, 通过群体智能去寻找最优的分区。通过数据仿真, 并与遗传算法、决策树、BP神经网络模型进行信用风险评价的实证对比研究, 结果表明, 该模型能够非常准确的找到数据对应的分区, 大大提高了信用评估的准确性, 降低了风险成本, 对信用风险的管理和控制具有很高的利用价值。     

考虑事件风险的在险价值研究

本文讨论了考虑事件风险的资产的在险价值方法,并以此对上海股票指数作了实证研究。这种方法用跳跃来描述事件风险,用跳跃-扩散过程来描述收益率过程。通过模拟退火算法来估计模型参数,利用随机模拟方法求得资产收益率的模拟分布,进而计算组合的在险价值。通过对上海指数的实证研究表明,资产的事件风险是不可忽略的,考虑事件风险的在险价值更加合理。     

Effects of Context and Feelings on Perceptions of Genetically Modified Food

Recently, there has been a surge of interest in the role of feelings in framing perceptions and decisions about risk, yet no study has specifically examined the impact of feelings on perceptions/judgments about biotechnology. This exploratory study investigated current perceptions of genetically modified (GM) food to examine (1) the effects of context (making judgments about GM food at the same time as rating other current areas of concern), and (2) the effect of feelings of dread (integral affect) and background feelings of stress (negative incidental affect) on risk judgments about GM food. An established psychometric method (semantic differential task) used with a sample of 126 adults (recruited "topic-blind," mostly from a student population) showed that, when rated in the context of other current concerns such as human cloning and Creutzfeldt-Jakob disease (CJD), there was less concern about GM food than might have been anticipated. Participants were recruited "topic-blind" in order to ensure that they were unaware that the focus of the research was on GM food specifically (and thus preventing biased recruitment to the study). Relative to 19 other current concerns GM food was "not dreaded," not viewed as "unethical," was judged as "controllable," and was seen as the least "risky" of all the issues studied. GM food was viewed as a "hot topic," a new risk, and as relatively unnatural (although it was not the highest rated concern on this scale). Ratings of risks across concerns by individuals experiencing high levels of negative incidental affect (stress) did not differ significantly from those reporting low stress.     

基于本体论的企业默会知识管理系统结构

默会知识的转化与共享一直是学术界和应用领域重点研究且难以突破的问题。本文分析了企业内默会知识的转化过程,提出了基于本体的企业默会知识转化模型和管理框架。基于此框架,建立了一个基于网络的默会知识交流共享平台,给出了基于本体论的企业默会知识管理系统结构。     

基于信用风险度的商业银行风险评估模型研究

本文依据商业银行信用风险的内涵,结合信用风险的不确定性和相对性特征,提出以"信用风险度"作为系统的输出,并针对传统模式识别评估方法的不足,构建了基于补偿模糊神经网络的信用风险评估预测模型,为有效转变信用风险的分类评估模式、提供更为全面的信贷决策支持奠定了基础.实证结果表明,该模型是一种较为有效的评估方法.     

Reducing Risk on Machinery: A Field Evaluation Pilot Study of Risk Assessment

A pilot evaluation of the ANSI B11-TR3 Machinery Risk Assessment/Risk Reduction (RA/RR) Guideline was conducted. The TR3 guideline was introduced into five companies on one machinery system in each company with a second machine system serving as a control. A pre-post investigation was performed with safety conditions measured pre and post in both treatment and control and with risk reduction score measured only in the treatment machine system. NIOSH provided a commercially available risk assessment software to facilitate the process. Evaluation measures included avoided injuries, reduced exposure to machinery hazards, pretest and posttest knowledge demonstration, assessment of group processes following training, correct implementation of the guidelines, and degree to which risk reduction recommendations were implemented. The qualitative results of this pilot effort appear to be the best indicators for the way ahead in industrial machine risk assessment. All companies indicated that they derived value in participating in this study and in conducting risk assessments. Quantitative study results suggest that: (1) as measured by the knowledge of the participants before and after the TR3 training, the guidelines can be effective at enhancing employee knowledge of safe machine operations and (2) although the injury reduction trends appear successful, the small sample size in the study size should be considered in interpreting these early results.     

基于利率风险的保险公司资产负债管理研究

应用无套利分析方法和二叉树方法对退保期权进行了定价,使用数值方法得到了中国市场的三次多项式利率期限结构模型,并应用以上结果建立了基于利率风险的久期缺口免疫模型,并使用保险公司实际资产负债数据对模型效果进行了检验。     

基于Ontology的跨组织知识整合方法研究

从知识整合的实际需求和研究现状出发,给出了跨组织环境下基于Ontology技术的知识整合流程,并结合语义网技术实现了知识集的闭包、查询与标准化同构等算法,开发了跨组织知识整合的原型系统。通过一个钢铁企业跨组织知识整合案例展示了原型系统的功能,说明知识的整合可以达到语义增值的效果;通过两个实验给出了原型系统的性能。     

基于动态风险乘数调整的CPPI和TIPP策略研究

本文引入一个动态风险乘数调整因子,对CPPI和TIPP的风险乘数m进行动态调整,提出一种新的基于动态风险乘数调整的CPPI(D-CPPI)和TIPP(D-TIPP)策略,其中m由固定乘数变为随股价变动的动态乘数。在股价上涨时,动态乘数调整因子随之上涨,当股价下跌时,动态乘数调整因子随之下跌,由此起到股价上涨时扩大参与获利,股价下跌时更好的进行向下保护的目的。结合我国股市的实际数据,分析不同行情和不同影响因素下动态风险乘数调整的CPPI(D-CPPI)和TIPP(D-TIPP)策略的执行绩效,并与传统的CPPI和TIPP策略比较,结果显示基于动态风险乘数调整的CPPI(D-CPPI)和TIPP(D-TIPP)策略总体优于传统的CPPI和TIPP策略。     

Risk Perception and Movies: A Study of Availability as a Factor in Risk Perception

Media effects on risk perception have often been explained by Tversky and Kahneman's availability principle, but research has not consistently supported it. What seem like media effects based on availability may be effects of new information. In an experimental study, entertainment movies depicting dramatic risk events were shown. They were found to produce no average effects on perceived risks in spite of large mood effects and being perceived as credible. We found, however, evidence of idiosyncratic effects of the movies, that is, people reacted immediately after the movies with enhanced  or  diminished risk beliefs. These reactions had faded after 10 days. Implications for the availability heuristic and risk perception are discussed.     

基于行为金融的证券组合风险管理研究

考虑人的心理行为因素,引入行为金融理论于风险管理主体的决策体系,指出了管理者的有限理性心理结构;基于BSV(Barberis-Shleifer-Vishny)思想建立了一种风险度量模型,据此调整了传统的行为证券组合理论;算法释例结果表明,该模型接近证券组合风险决策的实际情景。     

Using a Familiar Risk Comparison Within a Risk Ladder to Improve Risk Understanding by Low Numerates: A Study of Visual Attention

Previous experimental research provides evidence that a familiar risk comparison within a risk ladder is understood by low‐ and high‐numerate individuals. It especially helps low numerates to better evaluate risk. In the present study, an eye tracker was used to capture individuals’ visual attention to a familiar risk comparison, such as the risk associated with smoking. Two parameters of information processing—efficiency and level—were derived from visual attention. A random sample of participants from the general population (N= 68) interpreted a given risk level with the help of the risk ladder. Numeracy was negatively correlated with overall visual attention on the risk ladder (r_s=?0.28, p= 0.01), indicating that the lower the numeracy, the more the time spent looking at the whole risk ladder. Numeracy was positively correlated with the efficiency of processing relevant frequency (r_s= 0.34, p < 0.001) and relevant textual information (r_s= 0.34, p < 0.001), but not with the efficiency of processing relevant comparative information and numerical information. There was a significant negative correlation between numeracy and the level of processing of relevant comparative risk information (r_s=?0.21, p < 0.01), indicating that low numerates processed the comparative risk information more deeply than the high numerates. There was no correlation between numeracy and perceived risk. These results add to previous experimental research, indicating that the smoking risk comparison was crucial for low numerates to evaluate and understand risk. Furthermore, the eye‐tracker method is promising for studying information processing and improving risk communication formats.     

基于案例推理的应急决策支持系统研究

通过对危机管理应急决策的分析,指出了危机预案在应急决策中的重要作用,然后从危机信息处理的角度,结合决策支持系统技术和人工智能中的案例推理方法,构建了一类基于案例推理的应急决策支持系统,最后探讨了系统的体系框架和推理机制.     

Subsea Release of Oil from a Riser: An Ecological Risk Assessment

This study illustrates a newly developed methodology, as a part of the U.S. EPA ecological risk assessment (ERA) framework, to predict exposure concentrations in a marine environment due to underwater release of oil and gas. It combines the hydrodynamics of underwater blowout, weathering algorithms, and multimedia fate and transport to measure the exposure concentration. Naphthalene and methane are used as surrogate compounds for oil and gas, respectively. Uncertainties are accounted for in multimedia input parameters in the analysis. The 95th percentile of the exposure concentration (EC_95%) is taken as the representative exposure concentration for the risk estimation. A bootstrapping method is utilized to characterize EC_95% and associated uncertainty. The toxicity data of 19 species available in the literature are used to calculate the 5th percentile of the predicted no observed effect concentration (PNEC_5%) by employing the bootstrapping method. The risk is characterized by transforming the risk quotient (RQ), which is the ratio of EC_95% to PNEC_5%, into a cumulative risk distribution. This article describes a probabilistic basis for the ERA, which is essential from risk management and decision‐making viewpoints. Two case studies of underwater oil and gas mixture release, and oil release with no gaseous mixture are used to show the systematic implementation of the methodology, elements of ERA, and the probabilistic method in assessing and characterizing the risk.     

考虑复杂关联情境的城市典型生命线运行风险因素识别方法研究

城市典型生命线以供热、电力、燃气系统为代表,具有公共性强、风险性高、关联性显著的特点。研究城市典型生命线运行风险因素识别问题对于相关部门防范风险具有重要意义,但现实中由多系统、多风险因素以及各类关联形成的复杂关联情境增加了解决该问题的难度。为此,本文首先构建了具有层级网络结构的风险因素识别框架,然后提出了一种考虑复杂关联情境的风险因素识别方法,将各专家针对系统关联和风险因素关联给出的语言评价信息转化为二元语义,并将决策试验与评价实验室（DEMATEL）法和Two-Additive Choquet（TAC）积分算子扩展到二元语义环境,进而实现各类关联的综合集成,从而确定风险因素的排序和归类,便于决策者研判风险根源、明晰风险因素本质。最后,以北京某样区为例验证了所提方法的潜在应用价值,并根据识别结果制定了针对性的风险防范策略,能够为相关部门联调联动开展风险防范提供决策支持。