特种设备事故网络舆情演化规律模型研究

针对已有关于事故网络舆情演化的研究缺乏对事故影响力和政府干预力度的定量描述,引入事故影响力、政府干预力度和网络知情人数初始值3个因子,建立了特种设备事故网络舆情演化模型,很好地描述了人、机、环、管4个因素对事故网络舆情演化的影响。所建立的模型对事故影响力和政府干预力度进行分级和量化,分析了不同网络知情人数初始值对事故网络舆情演化的影响,为研究特种设备事故网络舆情演化规律、特种设备事故监管和政府干预提供理论依据。     

基于风险的城市埋地燃气管道安全评价模型及应用

城市埋地燃气管道一旦失效会产生泄漏,甚至引发火灾爆炸等事故,造成人员伤亡和财产损失等严重后果,影响社会稳定,因此其安全运行十分重要。由于城市地下环境的复杂性,使得埋地燃气管道失效的因素多种多样,且具有模糊性;由于城市地面状况各异,所以构成失效后果的因素也具有不确定性。文章以某市在役燃气管道为例,使用模糊数学语言表达了埋地燃气管道的失效可能性和失效后果,采用模糊综合评价模型对燃气管道的失效可能性和失效后果进行了评价,并以美国石油协会(API)风险矩阵表征了埋地燃气管道的风险等级,得到不同管道单元的风险级别和管道单元数,根据不同的风险等级采取不同的策略或措施,完善管道的完整性管理,降低管道的使用风险,确保城市燃气管网的正常安全运行。     

承压设备风险分析中失效后果加权模型研究

在分析失效可能性和失效后果具有不同权重的特点的基础上,提出一种失效后果加权的风险计算模型,该模型的等风险曲线很好地描述风险矩阵中的风险等级分布,并很好地解释风险矩阵分布的非对称性。所建立的模型能连续地将风险等级区域划分开来,以数学模型的形式描述不同风险等级的边界线,解决了传统风险等风险线跨越不同风险级别区域的问题。根据失效后果加权模型的风险计算结果,分析失效后果的权重大于失效可能性的权重的特点。     

考虑设备跌落的天然气计量站失效后果计算方法

天然气计量站阀门多且检定流程中频繁使用桁车,常规天然气站场的失效后果计算方法难以评估由此带来的影响及后果。为此,在API 581标准基础上,考虑阀门截断作用对机械损伤事故的影响,选取管段组储气量为最大天然气泄漏量,并以动量定理为依据,研究了桁车失效所引发的设备跌落事故,建立了潜在影响面积计算模型;将影响面积内损伤的管段及设备、泄漏的天然气、伤亡的人员等折算为经济损失,形成了考虑设备跌落的天然气计量站失效后果计算方法;将该方法应用于某天然气计量站。研究结果表明:设备跌落事故损失金额为机械损伤事故的3倍;当考虑设备跌落事故时,管段风险等级由低级上升为中低级。研究结果可为天然气计量站失效后果评价提供理论支撑。     

基于贝叶斯网络的城市地下燃气管网动态风险分析

为研究城市燃气管网风险的动态性,针对传统风险分析方法的局限性,提出基于贝叶斯网络的燃气管网动态风险分析方法。构建燃气管网失效蝴蝶结模型并将其转化为贝叶斯网络模型;在事故发生状态下更新事件失效概率,识别出关键因素;根据异常事件数据和贝叶斯理论,对基本事件失效概率进行实时动态改变;随之更新管网失效及各后果发生的概率,从而实现管网的动态风险分析。研究结果表明:该方法克服了传统风险分析方法的不足,可动态反映燃气管网失效和事故后果发生概率随时间变化的特征,能够为城市地下燃气管网的风险分析与事故预防提供参考。     

基于UHBs的输气管道高后果区泄漏燃爆事故分析

为探究输气管道高后果区中人的不安全行为（Unsafe Human Behaviors,UHBs）对输气管道泄漏燃爆事故发生的影响,结合模糊Bow-tie模型和贝叶斯网络对输气管道泄漏燃爆事故进行分析。构建基于T-S模糊故障树的输气管道泄漏燃爆模糊Bow-tie模型,并转化为贝叶斯网络;从人的不安全行为发生的可能性出发,将不同等级高后果区划分为不同等级人口敏感区;利用专家经验评判法得到不同等级人口敏感区基本事件的先验概率和中间事件的条件概率表;运用贝叶斯网络双向推理算法求解模糊Bow-tie模型。结果表明:随着地区人口敏感等级的提高,输气管道泄漏燃爆事故发生的概率随之增大,发现导致输气管道失效泄漏事故发生的最主要原因为施工破坏,失效原因与EGIG分析的结果基本相符,验证该方法在高后果区输气管道泄漏燃爆事故分析上的可行性,可为输气管道高后果区的安全管理提供决策依据。     

一种考虑认知不确定性的风险矩阵分析方法

为解决传统风险矩阵(CRM)元素等级分配的非一致性问题,提出一种考虑风险决策者认知不确定性的风险矩阵分析方法。首先,采用等级序数"乘法原则"计算风险指数,并将风险指数作为风险矩阵元素等级分配的依据。其次,引入风险决策者关注度系数,用来描述风险潜在信息的影响,并以指数的形式修正传统风险指数计算模型。最后,将修正后的连续概率后果分布(CPCD)映射到CRM。以风险指数最大化原则分配风险矩阵元素等级。运用该方法,分析某航天发射场某型低温液氢加注系统风险等级量化过程。结果表明,采用修正后的风险指数计算模型,能够得到不同加注工序不同关注度系数的风险等级分配方案,风险决策者的认知不确定性对低温液氢加注风险等级分配有影响。     

风险严重度指数法在毒气泄漏评价中的应用

为评价某区域或某设备潜在的毒气泄漏事故场景的风险水平,以对不同的风险等级进行风险控制和安全规划,详细介绍了工业事故风险评估方法ARAMIS所采用的风险严重度指数法.首先基于事故频率和后果的风险矩阵选取毒气泄漏事故场景;然后运用毒气当量浓度计算任意暴露时间下不同风险严重度等级所对应的特征距离,并根据同一风险等级内风险严重度指数与距离的线性关系计算任意点的风险严重度指数;最后应用1个实例分析了考虑所研究区域的风向概率后对风险严重度指数的真实影响,便于工厂或企业识别不同的风险等级,进行不同场景下风险水平的对比性研究,为其安全设计及风险分析提供了一种新的评估方法.     

客运索道定量风险评价方法研究

本文在吸收"十一五"研究成果的基础上,借鉴承压类特种设备风险评价技术成熟理论,提出了客运索道定量风险评估流程;通过引入设备特征系数、管理系数和失效系数对客运索道定量失效概率进行修正,将人员伤亡和经济损失两个定量失效后果转化为经济指标进行计算;给出了风险等级评定的准则,提出了客运索道定量风险评估具体方法和指标;通过给出应用案例,认为该方法具有可操作性,适合我国索道情况,应用前景良好。     

天然气净化厂内设备设施失效后果定量评价

天然气作为清洁能源,属于易燃易爆介质,突发状况下可能造成严重事故后果。天然气净化场站多分布在城市周边区域,但场站内设备布置比较拥挤,某台设备设施发生失效,可能会对设备本体及邻近设备造成影响,形成财产损失,更严重的情形会造成人员伤亡。本文通过事故后果分析工具SAFETI模拟酸气后冷器在2种风速下,水平方向发生3种不同孔径泄漏时,天然气遇到明火,发生喷射火和爆炸的场景。根据模拟结果,当泄漏介质总量较大时,风速越大,失效后果越严重,因为容器体积小,发生完全泄漏的时间较短,因此风速对其事故后果影响较小;在风速相同的情况下,事故后果影响范围也随着泄漏孔直径的增大而增大。由此可见,最严重的事故后果会发生在风速较大时水平方向的较大孔径泄漏。根据喷射火热辐射和爆炸超压的影响范围,可为后续场站设备安全运行管理提供决策依据。     

基于社会燃烧理论的突发公共卫生事件网络情绪传播模型

为有效引导和管控突发公共卫生事件网络舆情,考虑社会相关性和网络群体间情绪状态转移的不确定性,基于社会燃烧理论研究突发公共卫生事件网络情绪传播机制.首先基于社会燃烧理论分析网络用户群体的社会影响因素,建立未燃-阴燃-燃烧-抑燃-稳定(UDBFS)网络情绪传播模型和考虑干预措施的网络情绪传播模型;然后以新冠肺炎(COVID...     

成套装置动态风险管理专家系统

传统的设备管理模式造成设备非计划停机次数较多、故障频繁、可靠性和可用性不高等问题。为了解决上述问题,开发了成套装置动态风险管理专家系统,该系统包括动态风险监控、数据存储、失效模式及损伤机理判别、动态风险评估、风险辅助分析5个流程。该系统通过GIS平台进行展示,使用户可以直观、方便地查找、定位管线和容器位置,实现了高风险设备的风险展示、管道剩余寿命不足报警功能和管道冲蚀图例展示。将该专家系统进行了工程应用,得到容器和管道的潜在损伤机及其风险等级,针对不同风险等级的设备,生成了不同的检维修策略,为工程应用带来了很大的方便。     

Development of a risk-based maintenance (RBM) strategy for a power-generating plant

The unexpected failures, the down time associated with such failures, the loss of production and, the higher maintenance costs are major problems in any process plant. Risk-based maintenance (RBM) approach helps in designing an alternative strategy to minimize the risk resulting from breakdowns or failures. Adapting a risk-based maintenance strategy is essential in developing cost-effective maintenance policies.The RBM methodology is comprised of four modules: identification of the scope, risk assessment, risk evaluation, and maintenance planning. Using this methodology, one is able to estimate risk caused by the unexpected failure as a function of the probability and the consequence of failure. Critical equipment can be identified based on the level of risk and a pre-selected acceptable level of risk. Maintenance of equipment is prioritized based on the risk, which helps in reducing the overall risk of the plant.The case study of a power-generating unit in the Holyrood thermal power generation plant is used to illustrate the methodology. Results indicate that the methodology is successful in identifying the critical equipment and in reducing the risk of resulting from the failure of the equipment. Risk reduction is achieved through the adoption of a maintenance plan which not only increases the reliability of the equipment but also reduces the cost of maintenance including the cost of failure.     

Risk assessment of safety level in university laboratories using questionnaire and Bayesian network

Accidents in university laboratories not only create a great threat to students’ safety but bring significant negative social impact. This paper investigates the university laboratory safety in China using questionnaire and Bayesian network (BN) analysis. Sixteen influencing factors for building the Bayesian net were firstly identified. A questionnaire was distributed to graduate students at 60 universities in China to acquire the probability of safe/unsafe conditions for sixteen influencing factors, based on which the conditional probability of four key factors (human, equipment and material, environment, and management) was calculated using the fuzzy triangular theory and expert judgment. The determined conditional probability was used to develop a Bayesian network model for the risk analysis of university laboratory safety and identification of the main reasons behind the accidents. Questionnaire results showed that management problems are prominent due to insufficient safety education training and weak management level of management personnel. The calculated unsafe state probability was found to be 65.2%. In the BN analysis, the human factor was found to play the most important role, followed by equipment and material factor. Sensitive and inferential analysis showed that the most sensitive factors are personnel incorrect operation, illegal operation, and experiment equipment failure. Based on the analysis, countermeasures were proposed to improve the safe management and operation of university laboratories.     

Assessment of hazardous material risks for rail yard safety

This paper illustrates the application of quantitative risk assessment in a rail yard where tank cars of hazardous materials are received and stored. The assessment was conducted in response to community concerns about the safety of a proposed yard expansion. Six different chemicals are involved. For each one, the average monthly volume and the hazard of most concern are specified. We use an event tree populated with empirical data to compute the probability of a major spill in each case and we estimate the corresponding critical impact distances using available modeling tools. We find that for some of the chemicals, the relative increases in risk are appreciable, but that in all cases, the absolute levels of risk remain low. Then we identify some ways in which such an analysis can be extended and discuss the potential difficulties associated with these extensions.     

基于RBI的碳五石油树脂装置风险评估分析

从技术特点、实施效用等方面,对QRA与RBI两类风险评估技术进行比较,选择使用RBI技术方法对碳五石油树脂装置内静设备及管道实施风险评估。运用挪威船级社的ORBIT Onshore软件定量计算评估范围内设备、管道风险值,评定风险等级,辨识隐患设备,然后从后果、可能性两方面分析产生风险的主要影响因素,经分析得知碳五石油树脂装置受H2S、HCl腐蚀减薄影响轻微,但NaOH导致的碱应力腐蚀对聚合反应后序工段中部分管道设备失效可能性影响较大。最后根据装置内存在的不同损伤机理提出检验优化策略,为装置定期检验工作提供科学的决策支持。     

Uncertainty reduction for improved mishap probability prediction: Application to level control of distillation unit

At all levels, the understanding of uncertainty associated with risk of major chemical industrial hazards should be enhanced. In this study, a quantitative risk assessment (QRA) was performed for a knockout drum in the distillation unit of a refinery process and then probabilistic uncertainty analysis was applied for this QRA. A fault tree was developed to analyze the probability distribution of flammable liquid released from the overfilling of a knockout drum. Bayesian theory was used to update failure rates of the equipment so that generic information from databases and plant equipment real life data are combined to gain all available knowledge on component reliability. Using Monte Carlo simulation, the distribution of top event probability was obtained to characterize the uncertainty of the result. It was found that the uncertainty of basic event probabilities has a significant impact on the top event probability distribution. The top event probability prediction uncertainty profile showed that the risk estimation is improved by reducing uncertainty through Bayesian updating on the basic event probability distributions. The whole distribution of top event probability replaces point value in a risk matrix to guide decisions employing all of the available information rather than only point mean values as in the conventional approach. The resulting uncertainty guides where more information or uncertainty reduction is needed to avoid overlap with intolerable risk levels.     

大坝安全评价的可接受风险研究与评述

评述了国内外安全领域可接受风险研究的历史和现状.根据事故后果对风险进行分类,对不同类型风险给出风险定量表示方法,针对不同的风险定量表示方法,应用F-N曲线和ALARP准则研究相应的可接受风险确定方法,并就其在大坝安全风险评价领域的应用进行探讨.     

An integrated framework of safety performance evaluation for oil and gas production plants: Application to a petroleum transportation station

Safety performance evaluation is a significant way to ensure the safety of oil and gas production plants. Various evaluation methods have been proposed to make safety evaluation more consistent and scientific. However, a major concern is that many existing safety evaluation measurements are still subjective and are not easy to obtain in a uniform way, which can be attributed to the challenges that process plants faced such as people having different knowledge levels, equipment with dispersed locations and management with many processes. This paper aims to display the impact of risk factors on system safety level in a succinct and visual way that may be expected to overcome subjective opinions from experts and provide a more pertinent and practical safety strategies. To this end, an integrated framework is developed, which considers crucial risk factors from pipeline, static equipment, dynamic equipment and management. First, Fault tree analysis (FTA) is used to explicitly determine the crucial r risk factors. Then, a novel fuzzy cognitive map cooperating with relative degree analysis model (FCM-RDA) is proposed to deal with the weigh distribution opinions. Finally, considering the oil and gas production process is a complex system, a fuzzy comprehensive evaluation (FCE) is employed to calculate the overall safety level.