地震灾害下城市供水网络韧性评估及优化研究

为提升城市供水网络应对地震灾害的能力,基于性能响应函数(PRF)方法,引入基础设施网络均衡理论,设计综合考虑城市供水网络物理状态和输送能力的性能时程响应函数,构建贯穿结构和功能双维度的地震灾害下城市供水网络韧性评估方法;从灾害概率、灾害后果、恢复速度、恢复程度等4个关键因素出发,提出城市供水网络网状扩张、管道延性改造、增加恢复资源和提升恢复储备等韧性优化策略;以我国华东某市供水网络为例,定量评估不同优化策略下的韧性提升效果,提出不同决策场景下恢复资源r和恢复储备b的优化配置方法。结果表明:管网延性改造是提升供水网络韧性的有效措施,网状扩张能提升供水网络性能,但对韧性提升无明显作用,网状扩张后要注意增加网络恢复资源和恢复储备。     

Safety investment optimization in process industry: A risk-based approach

Process plant safety is a critical indicator of organizational performance. Adequate investment into safety practices to avoid future accident cost is therefore a beneficial strategy. The current approach to such investments in the process industry is driven largely by simple risk-based heuristics, insurance market premiums, organizational culture and management judgment. There is, however, an absence of an overarching methodology to assist such an effort. Therefore, there is a need for developing a robust decision-making framework for enabling systematic and optimal allocation of financial resources across all significant risk elements within a process plant.The present work proposes a safety investment optimization (SIO) framework for a typical process plant. Such an optimization approach targets maximal reduction of risk values across all potential hazards within the constraint of a given safety investment budget at the incipient stage of establishing a plant such that it saves future cost to company by reducing the risk from accidents. At the same time the framework takes into account the need to comply with the regulatory requirements imposed by the government. Additionally, access to insurance market as a strategy to transfer risk is also integrated. Finally, the residual risks are managed through investments in selective safeguards while ensuring that the benefits over-weigh the cost of such an exercise. For illustrating the application of the framework, a representative process plant with a select number of risk scenarios is chosen and all steps suggested by the framework are demonstrated quantitatively. It is anticipated that the proposed SIO framework will help optimal resource allocation for managing the risks implicit in a typical process plant.     

Statistical evaluation and analysis of safety intervention in the determination of an effective resource allocation strategy

This paper provides an analytical background for the development of an effective safety intervention program with the aim of minimizing incident rates. Safety intervention data were collected from the environmental health and safety department of an American-owned oil company in the Niger-Delta region of Nigeria. A safety model was developed to determine the safety intervention factors and interactions which minimize incident rates, with the aim of predicting a better resource allocation strategy. Five main safety intervention factors (factor A: leadership and accountability; factor B: qualification selection and pre-job; factor C: employee engagement and planning; factor D: work in progress; factor E: evaluation, measurement and verification) were highlighted and investigated to show their effects on incident rate performance. Analysis of variance test showed that four safety factors (A, C, D, and E) were significant. Statistical techniques such as response surface design plots were used to determine the resource allocation method. The developed safety model recommended the allocation of 16.66% of the available resources to the significant safety intervention activities in order to achieve the desirable incident rate. In order to reap the benefits of this research, it will be important to concentrate more efforts and resources on significant factors which have positive impacts in minimizing incident rates.     

Relationship between road traffic features and accidents: An application of two-stage decision-making approach for transportation engineers

Introduction: An efficient decision-making process is one of the major necessities of road safety performance analysis for human safety and budget allocation procedure. Method: During the road safety analysis procedure, data envelopment analysis (DEA) supports policymakers in differentiating between risky and safe segments of a homogeneous highway. Cross-risk, an extension of the DEA models, provides more information about risky segments for ranking purpose. After identification of risky segments, the next goal is to identify the factors that are major contributors in making that segment risky. Results: This research proposes a methodology to analyze road safety performance by using a combination of DEA with the decision tree (DT) technique. The proposed methodology not only provides a facility to identify problematic road segments with the help of DEA but also identifies contributing factors with the help of DT. Practical applications: The applicability of the proposed model will help policymakers to identify the major factors contributing to road accidents and analysis of safety performance of road infrastructure to allocate the budget during the decision-making process.     

基于案例推理的化工园区应急资源需求预测

为确定化工园区突发事故的应急资源需求,提出了一种基于案例推理的化工园区应急资源需求预测方法。该方法主要由三部分组成:(1)基于案例推理的模型构建;(2)化工园区事故的案例描述;(3)基于人工神经网络的案例适应。最后,以石化园区火灾爆炸事故的应急资源需求预测验证该方法的有效性。研究表明,该方法可以实时地对化工园区应急资源需求进行预测,为化工园区的应急资源储备和配置提供支持。     

Emergency resources demand prediction using case-based reasoning

The demand prediction on emergency resources is the premise and basis of optimal allocation of emergency resources. Nowadays, there are only few researches on this aspect in China and abroad. For this reason, the paper aims at the characteristics of emergency resource demand prediction and presents a method for emergency resource demand prediction using case-based reasoning (CBR), which is also a method based on risk analysis. This prediction method cannot only provide a basis for emergency resource reserve and allocation in future, but also provide a method and model support for the emergency resources allocation decision-making system to be constructed in future.     

社会应急资源监测系统及其应急响应能力研究

社会应急动员和资源筹募是救灾的关键。为有效组织和管理社会应急资源,充分发挥其在救灾中的作用,提出构建一个社会应急资源监测系统。这个监测系统将采集社会应急资源在社会系统中的分布、消耗和补给等的状态信息,为社会应急资源的提供者、各级社会管理部门、各级应急管理机构和系统管理员提供查询、分析和决策的接口;基于监测系统提供的信息,考虑应急救援的时间要求、数量要求、价值要求、经济性要求,建立社会应急资源和物流网络的应急能力评价指标体系。研究结果表明,根据社会应急资源监测系统提供的特定灾害应急所需的社会资源的状态信息,可确定该区域社会应急资源的可满足性、可应急性及物流网络对应急需求的满足情况,得到社会应急资源参与救援的可行性。     

Modeling using dynamic variables – An approach for the design of loss prevention programs

Records from The National Safety Council [National Safety Council, 2007. Safety Intervention Evaluation: A Systematic Approach. <http://www.acgih.org/events/ControlBand/Thomas_SafetyIntervention.pdf> (accessed 10.01.07)] have shown that in 2004 alone, on-the-job injuries to workers constituted 35% of total recorded injuries in the United States. This generated an associated cost of about $142.2 billion. Unfortunately, the safety intervention programs enforced at work places to mitigate such losses are driven mainly by intuition and experience of involved safety personnel. This paper details implementing a computer program to furnish safety personnel with an empirical basis for designing loss prevention programs based on historical safety data. The computer tool is driven by a dynamic mathematical model which adapts itself to variations in data patterns and explains the correlation between historical incident rates and corresponding resources committed to interventions. This study empowers the industry with a tool that is capable of forming the core of optimizing valuable human resource allocation in safety program designs.     

Probabilistic seismic multi-hazard loss estimation of Iran gas trunklines

The location of Iran in addition to holding the world's second-largest gas reserves, makes this country an important transporter of natural gas in the world. Moreover, Iran is a country that suffers from hazards associated with frequent destructive earthquakes, which can severely damage buried gas transmission networks, different losses correspond to individuals, social, environmental, and the property is expected. Therefore, it is essential to identify potential seismic hazards and assess their risk will be induced to the country. This paper is performing a comprehensive probabilistic loss assessment of the entire network of the Iran Gas Trunklines (IGAT) due to seismic multi-hazard failure using GIS-based analyses and the HAZUS methodology proposed by FEMA. In the current study, all kinds of seismic hazards are considered for analyzing the IGAT as a spatially-distributed infrastructure for being exhaustive. As a result, seismic hazard maps, repair rate maps, the IGAT expected damage state map, and the IGAT economic loss map are presented. As an example of the outputs of this study, the economic loss of the IGAT is predicted by up to 380 US dollars per segment, which is related to the most vulnerable segments of the pipelines. The outputs of the current research not only can help to plan for mitigating the probable seismic losses but also can help anyone, who are involved in designing and developing new gas transmission lines, to design new trunklines with a more degree of safety.     

公路突发交通事件应急资源配置效率研究*

为合理有效配置公路突发事件下的应急资源,从资源投入与产出角度建立3级评价指标体系,在此基础上将应急资源投入与产出比作为目标函数,引入数据包络分析法构建应急资源配置效率模型,采用TOPSIS法对应急资源配置方案效率进行排序。以新疆10个公路局应急资源配置效率为例,分析其资源投入与产出的冗余度,并对有效决策单元进行排序。结果表明:该模型能获得应急资源配置冗余度,并对其进行资源配置效率分析,从而为公路局进行有效资源配置提供参考。     

Environmental consequence analysis for resource depletion

Resource depletion is of concern to both present and future generations in terms of access to resources. It is a prominent impact category within life cycle assessment (LCA) and sustainability assessment. This paper examines existing resource depletion approaches and indicators in the context of natural gas depletion, and their limitations in modelling the wider environmental consequences of resource consumption. Some existing models assume substitution of scarce fossil fuels with an alternative fossil fuel or mix, but do not consider all of the subsequent change in impacts. An additional methodology is proposed to measure the impact changes when fossil fuel substitution occurs as a result of scarcity. The methodology will demonstrate the effect of resource scarcity for individual processes but also multiple processes which operate at different levels of resource consumption with varying degrees of impacts. The methodology is applied to a scarcity situation of natural gas in Australia, where black coal is substituted for gas. It is first applied to natural gas consumed for electricity generation only. In the second case, the methodology is applied to the substitution of natural gas for both electricity generation and hydrogen production. The varying impacts on emissions to air and water, together with solid waste generation and water depletion, as a result of the substitution are used to reflect the consequences of fossil fuel depletion. The indicators also provide information on the impacts of substitution in each product, thus enabling users to prioritise products based on the impacts produced during natural gas allocation.     

面向核应急响应的S-BOX集成模型

核事故引发的应急任务往往需要集成多个部门应急资源和能力来协同响应。这些海量核应急信息、知识汇聚于网络,其固有异构性限制了跨部门核应急集成的能力。为解决此问题,基于语义X列表理论提出核应急集成框架;以“事件-任务-资源”为主线构建本体结构列表和集成推理规则;给出假定核事故场景和资源、任务信息,搭建S-BOX模型和响应决策推理实验,验证了本方法可有效表达异构核应急信息与知识,实现按需集成。     

高速公路交通应急救援资源的配置

针对交通事故与救援资源存在随机性的特点,建立了交通救援资源配置的随机模型。根据高速公路特有的道路条件与交通机理,确定了模型中救援服务水平、事故概率的权重,配置点至事故点的权值以及随机资源等参数值。将所建立的模型与参数用于河南省高速公路的救援资源配置,研究表明,新的配置方案较好满足了交通事故高概率区域的救援需求,并且合理减少了救援需求区域的资源配置数量,为目前高速公路交通应急资源的科学配置提供了重要的参考依据。     

A CFD-based approach for gas detectors allocation

Accidental gas releases are detected by allocating sensors in optimal places to prevent escalation of the incident. Gas release effects are typically assessed based on calculating the dispersion from releasing points. In this work, a CFD-based approach is proposed to estimate gas dispersion and then to obtain optimal gas sensors allocation. The Ansys-Fluent commercial package is used to estimate concentrations in the open air by solving the governing equations of continuity, momentum, energy and species convection-diffusion combined with the realizable κ-ε model for turbulence viscosity effects. CFD dynamic simulations are carried out for potential gas leaks, assuming worst-case scenarios with F-stability and 2 m/s wind speed during a 4 min releasing period and considering 8 wind directions. The result is a scenario-based methodology to allocate gas sensors supported on fluid dynamics models. The three x–y–z geographical coordinates for the sensor allocation are included in this analysis. To highlight the methodology, a case study considers releases from a large container surrounded by different types of geometric units including sections with high obstacles, low obstacles, and no obstacles. A non-redundant set of perfect sensors are firstly allocated to cover completely the detection for all simulations releases. The benefits of redundant detection via a MooN voting arranging scheme is also discussed. Numerical results demonstrate the capabilities of CFD simulations for this application and highlight the dispersion effects through obstacles with different sizes.     

Quantitative risk assessment of the Italian gas distribution network

European Critical Infrastructures include physical resources, services, information technology facilities, networks and infrastructure assets, which, if disrupted or destroyed would have a serious impact on the health, safety, security, economic or social well-being of the Member States.The gas distribution network is a critical infrastructure and its failure can cause damage to structures and injury to people.The aim of this paper is to analyze and then assess the risk of the Italian high pressure natural gas distribution network.The paper describes an application of a methodology for quantitative risk assessment.Failure frequencies considered in risk calculation were found in the European Gas pipeline Incident data Group (EGIG) database, whereas consequences were computed as a function of pipe diameter and operating pressure for each section of the network. The results of this quantitative risk assessment is the determination of local and social risks for the Italian North East Area.     

Implementation of safety management systems in Hong Kong construction industry – A safety practitioner's perspective

IntroductionIn the 1980s, the safety management system (SMS) was introduced in the construction industry to mitigate against workplaces hazards, reduce the risk of injuries, and minimize property damage. Also, the Factories and Industrial Undertakings (Safety Management) Regulation was introduced on 24 November 1999 in Hong Kong to empower the mandatory implementation of a SMS in certain industries including building construction. Therefore, it is essential to evaluate the effectiveness of the SMS in improving construction safety and identify the factors that influence its implementation in Hong Kong.MethodA review of the current state-of-the-practice helped to establish the critical success factors (CSFs), benefits, and difficulties of implementing the SMS in the construction industry, while structured interviews were used to establish the key factors of the SMS implementation.ResultsResults of the state-of-the-practice review and structured interviews indicated that visible senior commitment, in terms of manpower and cost allocation, and competency of safety manager as key drivers for the SMS implementation. More so, reduced accident rates and accident costs, improved organization framework, and increased safety audit ratings were identified as core benefits of implementing the SMS. Meanwhile, factors such as insufficient resources, tight working schedule, and high labor turnover rate were the key challenges to the effective SMS implementation in Hong Kong.Practical applicationsThe findings of the study were consistent and indicative of the future development of safety management practice and the sustainable safety improvement of Hong Kong construction industry in the long run.     

国有高新技术企业核心资源安全策略研究

市场经济条件下,任何企业在运营中都存在着风险,高新技术企业面临的环境更具动态性和复杂性,其面对的运营风险也更为复杂。由于国有高新技术企业在资源获取、经营管理方面所具有的特殊性,其知识产权、企业文化、人才等核心资源已成为国有高新技术企业安全运营、保持持续竞争优势的必要条件,因此,针对国有高新技术企业现状,笔者围绕人力资源、知识产权、企业文化3方面的安全问题进行研讨,并提出相应的策略即包括实行知识产权保护制度、构建以人为本的企业文化、防止人才流失的管理层收购和股票期权策略。     

Risk analysis of Chongqing urban rail transit network

Urban rail network safety is a critical sector of urban public safety. However, there is no uniform standard for the safety evaluation of the urban rail network. This paper presents a novel methodology by integrating a multilevel decision tree with a fuzzy analytical approach to enhance urban rail network safety. The proposed methodology overcomes serious limitations such as subjectivity in the data and independence of the variables in decision-making processes. The proposed methodology is applied to the risk evaluation of the selected Chongqing rail transit lines and the Expo Line. The risk analysis is considered using the field data collected from these transit lines. The applied case studies confirm the general applicability of the methodology and the multilevel decision tree network. The main risk factors identified for the Chongqing rail traffic system are the terrorist threat, emergency management, and aging infrastructure which need to be investigated as a priority to mitigate risk associated with these infrastructures.     

信息资源共享系统可靠性模型的研究

信息资源共享系统可以充分利用信息的传递性、共享性,支持异地协同工作,使人们获取信息更为经济、便利、迅速。信息资源共享系统有其自身的脆弱性,系统安全可靠是最重要、最基本的需求。提高系统可靠性,预防不可靠因素是信息资源共享系统设计的关键之一。笔者提出了信息资源共享系统可靠性的概念。由信息资源共享系统可靠性理论导出信息资源共享系统可靠度,建立了信息资源共享系统可靠性优化的多目标数学规划模型。为信息资源共享系统可靠性建立了定量分析方法。最后以可靠度、成本和时间3个优化目标为例,进行了计算、分析。为信息资源共享系统可靠性设计提供了新方法。     

Prioritizing highway safety improvement projects: A multi-criteria model and case study with SafetyAnalyst

This paper presents a multi-criteria model for prioritizing highway safety improvement projects, in which a set of criteria related to the project’s technical, economic, and social impacts are properly weighted in consideration. The proposed model features an Analytical Hierarchy Process (AHP) framework to tackle the multi-criteria decision making problem. Different from the conventional AHP, this paper adds a fuzzy scale level between the criteria level and the alternative level, which offers the advantage of preventing the vagueness and uncertainty on judgments of the decision-maker(s). Such a unique modeling feature is further embedded with a non-linear optimization formulation to maximize the consistency in pair-wise comparison and weight estimation for each criterion. Case study results reveal that the proposed model is efficient not only for selecting the most suitable project for a specific site, but also for determining the priorities for implementing those suitable projects among multiple sites given the budget constraint. Comparative study between the proposed model and the existing ranking methods has also indicated its capability to capture the comprehensive impacts of all contributory factors which have been neglected by most existing single multi-criteria approaches during the safety project selection process. The clarity of model inputs, ease of synthesizing the final score of each candidate project, and the interpretation of results with respect to different selection criteria offer its best potential to be used as an effective tool for highway safety managers to assess and refine the safety improvement investments.