Environmental risk mapping of pollutants: State of the art and communication aspects

Risk maps help risk analysts and scientists to explore the spatial nature of the effects of environmental stressors such as pollutants. The development of Geographic Information Systems over the past few decades has greatly improved spatial representation and analysis of environmental information and data. Maps also constitute a powerful tool to communicate the outcome of complex environmental risk assessment to stakeholders such as the general public and policy makers. With appropriate cartography one can improve communication and thus bridge the gap between experts and users. Appropriate risk communication is pivotal to risk management, decision making and implementation and may prevent unnecessary concern about environmental pollutants. However, at present few risk maps are specifically tailored to meet the demands of such defined uses.This paper presents an overview of the most important types of risk maps that can be distinguished using examples from the scientific literature: contamination maps, exposure maps, hazard maps, vulnerability maps and ‘true’ risk maps. It also discusses, in a general way, the most important issues that need to be addressed when making risk maps for communication purposes: risk perception, target audience, scale and spatial aggregation and visualisation such as use of colours and symbols. Finally, some general rules of thumb are given for making environmental risk maps for communication purposes.     

风险分析方法在建设项目造价控制中的应用

本文针对建设项目造价控制提出了一种风险分析方法,阐述了风险分析的概念及其应用于建设项目造价控制的基本思路、方法和具体步骤,分析了建设项目主要的风险因素、风险评估体系、主要风险解决方案以及采取的风险对策。利用这种方法可以有效地预测建设项目潜在的造价风险,并准确控制项目最终造价水平,积极主动地防止造价偏差,从而将工程造价控制在一个可预测的水平。风险分析方法可以用在项目实施的准备阶段及项目施工阶段直至工程竣工,贯穿于项目建设的全过程,而且是一个动态过程、定期监控过程。风险分析方法的要点在于风险的识别、评估、监控以及对策研究。风险分析方法在建设项目造价控制中的应用前景十分广泛。     

A fuzzy inference-based approach for building damage risk assessment on mining terrains

Reliable evaluation of risk of building damage due to the mining impact is problematic owing to the magnitude, diversity and uncertainty of factors that may affect the surface, as well as the subjective character of methods of assessing resistance of the objects. The uncertainty and ambiguity elements in the decision process can be accounted for by fuzzy inference method. This tool employed together with GIS enabled one to integrate such diverse factors affecting damage risk as surface deformations and resistance of building objects, taking into account uncertainty of data and subjectivity of evaluation of experts making the assessment.The results of investigations of the damage risk model based on fuzzy inference are presented in the paper. The successive stages of working out a fuzzy model are presented, the most important stages indicated and the choice of specific elements of the model justified. The advantages of fuzzification are presented on the example of building data subjected to the mining impact in one of the Polish mining areas.     

项目风险评价方法及进展研究

参考了一般风险评估理论,对风险评估各种方法的特点和发展状况进行了详细的介绍和分析,对当前风险评估方法还存在的问题和未来发展方向提出了自己的见解,从而为项目管理者提供决策支持。     

Combining engineering and data-driven approaches: Development of a generic fire risk model facilitating calibration

Fire risk models support decision making for engineering problems under the consistent consideration of the associated uncertainties. Empirical approaches can be used for cost-benefit studies when enough data about the decision problem are available. But often the empirical approaches are not detailed enough. Engineering risk models, on the other hand, may be detailed but typically involve assumptions that may result in a biased risk assessment and make a cost-benefit study problematic. In two related papers it is shown how engineering and data-driven modeling can be combined by developing a generic risk model that is calibrated to observed fire loss data. Generic risk models assess the risk of buildings based on specific risk indicators and support risk assessment at a portfolio level. After an introduction to the principles of generic risk assessment, the focus of the present paper is on the development of a generic fire risk model for single family houses as an example. The risk model considers the building characteristics of a single family house as well as the uncertainties associated with the fire spread in a building and the intervention of the fire brigade.     

A flood risk assessment to municipal infrastructure due to changing climate part I: methodology

Extreme rainfall events that are occurring more frequently as an effect of climate change and variability are causing increasing damages to municipal infrastructure. A methodology is developed to quantify the risk to municipal infrastructure from climate change-related flooding. The risk is measured using a combination of flow/frequency, stage/damage and damage/frequency curves. The measure of risk is termed the Risk Index and calculated for each infrastructure element within a municipality. The risk is aggregated and summed by spatial unit and presented in the form of risk tables and maps. The risk index takes into account both quantitative and qualitative information obtained from research and interviews with technical experts. The results from the application of the methodology to a municipality will lead to better policy and informed decision making.     

Probabilistic risk assessment of highway tunnels

Many approaches to risk analysis in tunnels have been proposed by both international and national authorities over the last few years. Many safety problems have been discussed and a large number of important risk factors and hazards in tunnels have been identified. The concept of risk analysis in the scope of tunnel risks is, however, still under development; particularly an overall idea about the risk management concept is still missing. The paper introduces the concept of risk analysis in the scope of risk management and employs methods well-known in aeronautics and aircraft industry, yet, still unused in tunnels. The proposed methodology enables building and refurbishing costs minimization subject to preservation of satisfactory safety level. The outcomes of the proposed method have clear technical and economic interpretation and create a strong support tool for the decision making process. The paper also includes a case study of the Strahov tunnel in Prague, Czech Republic.     

皖赣铁路隧道设计阶段地质风险评估探讨

在现有资料的基础上,运用风险分析与评估的专家调查法、核对表法,对皖赣铁路电气化改造工程可研、初步设计阶段改线段新建铁路隧道的地质风险评估进行了探讨,得出了一些有益的结论,具有一定指导意义。     

Safety risk assessment of Jiangshun Suspension Bridge in design stage

This paper presents a safety risk assessment approach with a case study, where a combined analytic hierarchy process (AHP)–fuzzy clustering–Delphi (AFD) method is used for the risk assessment of the Jiangshun Suspension Bridge. Based on the engineering background and experience of the experts, the risk factors are defined. The weights of risks are analysed by the AHP method. In order to ensure the accuracy of expert assessment, the fuzzy clustering method is used to analyse the results from the experts mentioned above. Then, combined with the results of the risk weight from AHP, the risk rank of risk factors, risk hierarchies and the whole bridge scheme are worked out. This study shows that the risk rank of the Jiangshun Suspension Bridge is II, which is medium risk, and can be accepted conditionally. The AFD combined method can be used to analyse the safety risk assessment of suspension bridges, as illustrated in this study.     

A risk management approach to safety assessment of trenchless technologies for culvert rehabilitation

Proper functioning of culverts is not only critical to protecting the transportation system from flooding but also critical to maintaining the expected service life of the overall transportation system. During the service life of culverts, they deteriorate due to many reasons such as corrosion caused by road salt, blockage by debris and sediment, poor construction techniques, etc. Trenchless technologies have been used by several State Departments of Transportation (DOTs) to rehabilitate deteriorated drainage structures without disrupting the traffic and within a relatively short span of time. These technologies provide many benefits in terms of cost, time, quality, and expected service life. However, the safety aspects of these techniques have not been discussed and documented in detail probably due to the complexity and the lack of safety standards and specifications directly associated with the techniques. This paper discusses the application of a risk assessment framework to assess potential safety issues of currently available trenchless technologies for culvert rehabilitation. The findings of the study will provide additional information to improve the decision making process in selecting and planning culvert rehabilitation projects.     

Synergy and other ineffective mixture risk definitions

A substantial effort has been spent over the past few decades to label toxicologic interaction outcomes as synergistic, antagonistic, or additive. Although useful in influencing the emotions of the public and the press, these labels have contributed fairly little to our understanding of joint toxic action. Part of the difficulty is that their underlying toxicological concepts are only defined for two chemical mixtures, while most environmental and occupational exposures are to mixtures of many more chemicals. Furthermore, the mathematical characterizations of synergism and antagonism are inextricably linked to the prevailing definition of 'no interaction,' instead of some intrinsic toxicological property. For example, the US EPA has selected dose addition as the no-interaction definition for mixture risk assessment, so that synergism would represent toxic effects that exceed those predicted from dose addition. For now, labels such as synergism are useful to regulatory agencies, both for qualitative indications of public health risk as well as numerical decision tools for mixture risk characterization. Efforts to quantify interaction designations for use in risk assessment formulas, however, are highly simplified and carry large uncertainties. Several research directions, such as pharmacokinetic measurements and models, and toxicogenomics, should promote significant improvements by providing multi-component data that will allow biologically based mathematical models of joint toxicity to replace these pairwise interaction labels in mixture risk assessment procedures.     

Factors affecting contractors’ risk attitudes in construction projects: Case study from China

Risk-based decision making (RBDM) is critical in successful construction project management, in which decision makers’ attitudes towards risks play an important role. Most previous studies in construction project risk management have been focusing on the factors contributing to the success of risk management, but little attention was given to factors significantly affecting decision makers’ risk attitudes in construction projects. To improve RBDM, we investigate the critical factors affecting contractors’ risk attitudes in construction projects in China in this research. Literatures reviews, interviews and questionnaires are used for the identification of factors affecting contractors’ risk attitudes. Statistical methods of ranking analysis and factor analysis are also implemented for verification and further analysis. The results show that the most important three factors are: “consequences of decision making”, “engineering experience”, and “completeness of project information”. Results from factor analysis on the identified critical factors reveal that they can be grouped into four categories, namely: (1) knowledge and experience; (2) contractors’ character; (3) personal perception; and (4) economic environment. The significance of this research is that the findings do not only provide decision making support for contractors by deepening their understandings of the factors that affect their risk attitudes, but also serve as a useful reference for further studies under this topic.     

Using fuzzy multiple criteria decision making approach to enhance risk assessment for metropolitan construction projects

The undertaking of construction projects in metropolitan areas is a risky, competitive, and dynamic proposition requiring a reliable risk assessment model for adequate planning. This study employs a fuzzy multiple criteria decision making (FMCDM) approach to systematically assess risk for a metropolitan construction project. Consistent fuzzy preference relations (CFPR) are used to measure and investigate the relative impact on project performance of twenty identified risk factors included in four risk dimensions. The fuzzy multiple attributes direct rating (FMADR) approach is employed to analyze the occurrence probability of multiple risk factors. Furthermore, the level of risk for the overall project caused by individual risk factor is evaluated with the synthesized analysis of the relative impacts and probability of occurrence. The implementation of FMCDM makes the proposed risk assessment approach more reliable and practical than the traditional statistical approach. The proposed approach can be employed to effectively evaluate the overall project risk, and can be benefited to efficiently identify significant risks of a metropolitan construction project.     

Development of web-based system for safety risk early warning in urban metro construction

At present, underground urban metro construction accidents in China are rising with the rapid growth of urbanization and infrastructure investment. Real-time safety and risk management during urban metro construction has become extremely important but is very difficult, time-consuming and unreliable due to the lack of information and experienced managers. This paper presents the development and application of a web-based system for safety risk early warning in urban metro construction. A hybrid data fusion model based on multisource information (monitoring measurements, calculated predictions, and visual inspections) is employed to imitate human experts to give safety risk assessment and early warnings automatically. In addition, it has significantly improved information collection, sharing and communication by establishing a collaborative platform instead of traditional manual management. The system has been successfully applied to several metro construction projects and has perfected the safety management performance in the cities of Wuhan, Shenyang, Zhengzhou and Kunming in China.     

A fuzzy approach to construction project risk assessment

The increasing complexity and dynamism of construction projects have imposed substantial uncertainties and subjectivities in the risk analysis process. Most of the real-world risk analysis problems contain a mixture of quantitative and qualitative data; therefore quantitative risk assessment techniques are inadequate for prioritizing risks. This article presents a risk assessment methodology based on the Fuzzy Sets Theory, which is an effective tool to deal with subjective judgement, and on the Analytic Hierarchy Process (AHP), which is used to structure a large number of risks. The proposed methodology incorporates knowledge and experience acquired from many experts, since they carry out the risks identification and their structuring, and also the subjective judgements of the parameters which are considered to assess the overall risk factor: risk impact, risk probability and risk discrimination. All of these factors are expressed by qualitative scales which are defined by trapezoidal fuzzy numbers to capture the vagueness in the linguistic variables. The most notable differences with other fuzzy risk assessment methods are the use of an algorithm to handle the inconsistencies in the fuzzy preference relation when pair-wise comparison judgements are necessary, and the use of trapezoidal fuzzy numbers until the defuzzification step. An illustrative example on risk assessment of a rehabilitation project of a building is used to demonstrate the proposed methodology.     

基于加权贝叶斯网络的森林火灾风险评估

基于森林火灾风险因素的不确定性及应急管理和救援力量介入对森林火灾风险管控的影响,构建森林火灾风险评估指标体系。结合领域专家的经验和知识,基于贝叶斯网络模型,绘制森林火灾风险网络图,对森林火灾发生的不确定性进行明确和处理;基于信息增益计算各指标权重,确定网络图中各指标节点的贡献值,建立加权贝叶斯网络评估模型。对我国内蒙古自治区森林火灾风险开展评估。分析结果表明,该评估模型能够有效对森林火灾的风险进行评估,具有一定的实际应用价值。     

考虑主观风险态度的建筑结构地震风险决策

针对全寿命周期成本最小准则不能反映决策者主观风险态度的不足,引入效用理论这一经典决策模型探讨风险厌恶态度对地震风险决策的影响。以12栋抗震设计等级不同的办公楼为例,分别从公共决策者风险厌恶视角的抗震设计和私人决策者风险厌恶视角的地震保险投保两个方面,研究了降低风险和转移风险两种行为的最优决策问题。结果表明,最优的抗震设计等级随风险厌恶程度的加大而提升;业主在购买地震保险时,随风险厌恶程度的加大和结构抗震等级的下降,倾向于接受更高的地震保险费用。     

The industrial role in risk assessment

Industry has a major role in the assessment and management of risk to society from its operations. Much of the basic knowledge of manufacturing operations, product distribution, use and ultimate disposal of products and byproducts resides in industry. Basic data on the health and environmental effects of materials in commerce has been generated by industry. This information must be utilized in the evaluation of risk so that appropriate management decisions can be made. Experience gained in the industrial sector with risk assessment and management should be of value to government in its oversight role on behalf of society. There is growing realization in both industry and government of the need for more effective communication of risk to the general public in the context of management decisions.     

Fuzzy‐based gaps assessment of flood disaster risk reduction management systems in Metro Manila,Philippines

Planning and prioritization in flood disaster risk reduction (FDRR) is critical and often tedious to both planners and decision‐makers. In Metro Manila, Philippines, flooding is a perennial problem that requires regular assessments and updating of its municipal‐based FDRR management systems. A simple, but practical approach may prove useful in the identification of priority schemes, especially when the need for improvement is urgent and resources are limited. This study provides a simple quantitative approach to gaps assessment for FDRR management systems using a fuzzy multiattribute decision‐making technique. This is demonstrated by utilizing the stakeholders’ perceptions and field information obtained during the aftermath of the tropical storm Ketsana in 2009. Study results show that the gaps can be quantified and ranked to establish the priority schemes for the improvement of the FDRR management systems in Metro Manila, focusing mainly on the following FDRR management systems: prevention, preparedness, response and disaster recovery.