民航机务维修系统安全风险监测

从人的因素、飞机的因素、环境因素和管理因素4方面分析了民航机务维修系统安全风险影响因素,结合专家调查意见建立了机务维修系统安全风险监测指标体系,并给出各个指标的含义及其衡量方法。根据机务维修系统安全风险指标及其数据特点,建立了行业机务维修系统安全风险模糊综合评价模型,并进行实例分析。结果表明,采用笔者建立的指标体系和风险模型可以方便地进行机务维修系统的安全风险评价和预警,从而找出主要的安全风险影响因素,为采取安全风险管理措施提供依据。     

航空公司运行风险因子交互作用规律研究

针对影响航空公司飞机运行安全的风险因子具有关联性及因果性的特点,从人、机、环、管四方面分析影响航空公司飞机安全运行的风险因子,由专家及航空公司运行人员对风险因子两两之间的相关性及因果性进行判断,结合图论中的方法构建风险因子的邻接矩阵,并利用MATLAB仿真软件构建邻接矩阵的可达矩阵,然后对可达矩阵进行分解并将风险因子分为5个层次,构成一个多级递阶的网络模型,明确不同层次中的风险因子及其因果关联影响,揭示风险因子交互作用的内在规律.结果表明,网络结构模型具有良好因果关系及层次,说明只有通过系统安全管理手段避免风险因子之间的交互作用才能更加有效控制风险的发生.     

基于民航安全信息文本挖掘的进近着陆致险因素分析

为有效识别飞行进近着陆阶段致险因素,以进近着陆不安全事件为对象,利用Python语言和文本挖掘方法对文本进行预处理,获取包含关键特征值和特征权重的高维稀疏原始特征向量集合;利用卡方统计对致险因素原始特征项进行降维,得到30个维度文本特征项,借助词云图将文本挖掘结果可视化;通过人为因素、飞机故障、环境因素和管理因素4个层...     

中国民航业安全风险监测与仿真研究

根据系统安全的思想,通过对航空安全历史数据的分析和专家经验,从人员、设备设施、环境和组织管理4个方面,提出中国民航机务、空管、飞行、机场4个分系统安全风险监测指标体系,共102个风险因素指标,并合成为27个行业安全风险监测指标。以民航历史数据为样本,建立资源优化神经网络(RON)模型,将安全风险监测指标与中国民航安全指数相联系,分析安全指数的关键影响因素,达到安全管理决策支持的目的。通过建立的风险监测指标体系和RON模型,可以实现民航整个行业、各分系统及单个指标的安全风险监测和预警。     

Safety climate, attitudes and risk perception in Norsk Hydro

The aims of this paper are to test mental images of risk and to present some results of a survey of safety climate, employee attitudes, risk perception and behaviour among employees within the industrial company Norsk Hydro. Two mental images were tested. They are both based on the assumption that it is possible to make a distinction between cognitive and affective processes involved in risk perception. The first model was the ‘rationalistic’ approach, which assumes that the affective component of risk perception is influenced by cognitive judgements. The justification for the second model is found in Zajonc's [Zajonc, R.B., 1980. Feeling and thinking. Preferences need no inferences. American Psychologist 35 (2), 151–175] conclusion that emotions are precognitive. In this model, entitled the ‘mental imagery’ approach, emotion is seen as the driving force affecting cognition of risk and safety. Employees at 13 plants have answered a self-completion questionnaire. The plants belonged to the agricultural, aluminium, magnesium and petrochemical divisions within Norsk Hydro. A total of 731 respondents replied to the questionnaire. The mental imagery approach was somewhat better fitted to the data than a rationalistic approach. Safety climate and employee attitudes towards safety and accident prevention contributed significantly to the variance in employee occupational risk behaviour. Worry and the extent to which the employee felt safe/unsafe was the most important predictor for the cognitive judgement of risk. Acceptability of rule violations seemed to be the most important predictor of behaviour, probably because acceptability also affected how often the respondents took chances and broke safety rules.     

基于熵权和模糊综合评价的航空公司安全风险研究

针对航空公司安全风险诸多影响因素的模糊性,引入模糊综合评价理论对航空公司安全风险进行评价,从机组、飞机、环境和管理4个方面提出了航空公司安全风险评价的指标体系,采用熵权和层次分析法确定评价指标的拟合权重,建立了航空公司安全风险评价的模糊综合评价模型。以该模型对国内某航空公司安全风险状况进行评价。分析认为,该航空公司的安全风险介于高风险与较高风险之间,急需加强安全防范,尤其应该加强飞行机组和飞机的安全管理。     

基于熵权-HDT的航空器维修人误概率确定

人误是造成民用航空维修差错的主要因素。为确定不同情境下人误发生概率,结合某维修基地具体情况,采用熵权法确定主要的影响因子,并基于全决策树法分析主要影响因子对航空器维修人误概率的影响程度。计算结果显示,该维修基地人因可靠性的主要影响因子包括航空器维修人员的安全态度、技能、沟通、工作环境、压力以及工段长领导能力。根据各主要影响因子的不同品质描述等级组合,确定该情境下航空器维修人员的人误概率。鉴于该维修基地人因可靠性影响最明显的因子是"沟通",提出信息及时交流、明确沟通重要性等解决措施。     

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.     

基于CREAM和贝叶斯网络的航空维修人为差错概率预测

航空维修差错不仅严重威胁着飞行安全,同时也会增加航空公司的维修成本。针对航空维修人员发生差错成因的复杂性以及历史事故数据缺乏的情况下,将人因可靠性与失误分析方法（CREAM）和贝叶斯网络（BN）相结合,提出一种改进的维修差错分析模型。根据维修任务构建相应的贝叶斯网络模型,为各子节点设置条件概率表（CPT）;基于维修基地的实际维修环境,对行为形成因子（PSFs）进行评估,得到共同绩效条件（CPCs）的水平;利用各CPC因子下各个行为功能失效模式的权重因子,对各认知活动进行失效概率的修正;将修正概率作为贝叶斯网络根节点的输入,利用推理机制,得到差错发生概率。通过案例分析和计算,验证了所述方法的可行性和有效性。     

基于灰色多层次的航空公司飞行安全评价研究

针对影响航空公司飞行安全诸多因素具有的灰色性,引入灰色理论对航空公司飞行安全进行风险评价,从机组、飞机、环境和管理4个因素,提出航空公司飞行安全风险评价的指标体系,采用层次分析法(AHP)确定评价指标权重,建立基于灰色多层次的航空公司飞行安全风险评价模型。根据建立的模型,对国内某航空公司飞行安全状况进行评价,通过分析认为该航空公司的飞行安全介于高风险与较高风险之间,急需加强安全防范,尤其应该加强对飞行安全管理。综合评价的结果为航空公司制定飞行安全措施及预防对策提供科学的依据。     

机务维修风险管理研究

机务维修是影响飞行安全的重要环节,随着我国民航业的不断发展,机务维修能力不足的问题日益严重,急需进行风险管理研究。首先选择SHELL模型进行风险因素识别,从人员(L)、人员与人员(L-L)、人员与软件(L-S)、人员与硬件(L-H)、人员与环境(L-E)方面系统的识别出机务维修风险因素;在此基础上,针对机务维修风险因素相互影响的特点,选择模糊网络分析法进行风险评价,得出权重排序;针对评价结果,提出相应的风险控制措施:加强维修资源管理、建立良好的安全文化、强化维修队伍建设、改善维修工作条件。最终结果表明,此研究有助于系统全面的进行机务维修风险因素识别,科学的评价风险因素,合理的制定风险控制措施,对机务维修风险管理提供了一定的借鉴意义。     

An extension of the fuzzy improved risk graph and fuzzy analytical hierarchy process for determination of chemical complex safety integrity levels

The risk graph (RG) is widely used to evaluate the safety integrity level (SIL) of safety instrument systems (SIS). However, subjective opinion-based conventional RGs cannot provide successful results for the problems of risk parameters, such as shortages or lack of data; hence, the output of a conventional approach lacks sufficient reliability. We introduced the fuzzy improved risk graph (FIRG), an extension of fuzzy set theory, to deal with possible ambiguities during SIL study and increase the reliability of conventional RGs. In the present study, the levels of consequences defined as linguistic terms were converted into qualitative intervals; therefore, by correlating the proposed approach with experts’ opinions and attributing weight factors, a desired SIL value was obtained. The output of this new approach can be compared directly with quantitative risk assessment techniques to improve the safety performance of industrial systems.     

What-You-Look-For-Is-What-You-Find – The consequences of underlying accident models in eight accident investigation manuals

Accident investigation manuals are influential documents on various levels in a safety management system, and it is therefore important to appraise them in the light of what we currently know – or assume – about the nature of accidents. Investigation manuals necessarily embody or represent an accident model, i.e., a set of assumptions about how accidents happen and what the important factors are. In this paper we examine three aspects of accident investigation as described in a number of investigation manuals. Firstly, we focus on accident models and in particular the assumptions about how different factors interact to cause – or prevent – accidents, i.e., the accident “mechanisms”. Secondly, we focus on the scope in the sense of the factors (or factor domains) that are considered in the models – for instance (hu)man, technology, and organization (MTO). Thirdly, we focus on the system of investigation or the activities that together constitute an accident investigation project/process. We found that the manuals all used complex linear models. The factors considered were in general (hu)man, technology, organization, and information. The causes found during an investigation reflect the assumptions of the accident model, following the ‘What-You-Look-For-Is-What-You-Find’ or WYLFIWYF principle. The identified causes typically became specific problems to be fixed during an implementation of solutions. This follows what can be called ‘What-You-Find-Is-What-You-Fix’ or WYFIWYF principle.     

Pedestrian falls: A review of the literature and future research directions

IntroductionPedestrian falls (PFs) – falls in public spaces without collisions with other road users – are a significant cause of serious transport-related injuries, amounting to three-quarters of all pedestrians admitted to hospital.MethodsThis scoping review examined peer-reviewed research on PFs published between 1995 and 2015. Electronic databases (Scopus, SafetyLit, and PubMed) were used to find studies identifying PFs or outdoor falls (the latter also including falls in gardens).ResultsWe identified only 28 studies reporting relevant information on PFs (i.e., 15 prospective, 10 retrospective, and 3 intervention studies). The results show that more walking is related to a lower risk of PFs. Older people, especially older women, have a higher risk of (injurious) PFs. Outdoor fall victims have equally good or better health characteristics and scores on balance tests compared to those who have not experienced such falls. Road factors such as uneven surfaces, busy junctions, stairs, and slippery surfaces seem to play an important role in PFs, but much of the research on these factors is of a qualitative nature.ConclusionsPF victims are generally in good health (apart from normal age-related problems) but at risk due to road factors.Practical applicationsWe recommend to adopt a human factors approach. The road system should be adapted to human capabilities and limitations including those of pedestrians. Measures such as preventing uneven surfaces and good winter maintenance seem to be effective. However, we advise more quantitative research on road factors to inform design guidelines and standards for public space authorities given the qualitative nature of current research on road factors.     

A fuzzy logic and probabilistic hybrid approach to quantify the uncertainty in layer of protection analysis

Layer of protection analysis (LOPA) is a widely used semi-quantitative risk assessment method. It provides a simplified and less precise method to assess the effectiveness of protection layers and the residual risk of an incident scenario. The outcome failure frequency and consequence of that residual risk are intended to be conservative by prudently selecting input data, given that design specification and component manufacturer's data are often overly optimistic. There are many influencing factors, including design deficiencies, lack of layer independence, availability, human factors, wear by testing and maintenance shortcomings, which are not quantified and are dependent on type of process and location. This makes the risk in LOPA usually overestimated. Therefore, to make decisions for a cost-effective system, different sources and types of uncertainty in the LOPA model need to be identified and quantified. In this study, a fuzzy logic and probabilistic hybrid approach was developed to determine the mean and to quantify the uncertainty of frequency of an initiating event and the probabilities of failure on demand (PFD) of independent protection layers (IPLs). It is based on the available data and expert judgment. The method was applied to a distillation system with a capacity to distill 40 tons of flammable n-hexane. The outcome risk of the new method has been proven to be more precise compared to results from the conventional LOPA approach.     

Are pilots at risk of accidents due to fatigue?

PROBLEM: There is concern in the aviation community that pilot schedules can lead to fatigue and increased chance of an aviation accident. Yet despite this concern, there is little empirical analysis showing the relationship between pilot schedules and commercial aviation accidents. This study attempts to demonstrate an empirical relationship between pilot schedules and aviation accidents. METHOD: Data for human factors-related accidents and pilot work patterns were identified. The distribution of pilot work schedule parameters for the accidents was compared to that for all pilots using a chi-square test to determine if the proportions of accidents and length of duty exposure were the same. If the distributions are the same, then one could infer that pilot human factor accidents are not affected by work schedule parameters. RESULTS: The proportion of accidents associated with pilots having longer duty periods is higher than the proportion of longer duty periods for all pilots. DISCUSSION: There is a discernible pattern of increased probability of an accident as duty time increases for commercial aircraft pilots in the United States. IMPACT ON INDUSTRY: The analysis suggests that establishing limits on duty time for commercial pilots would reduce risk. Such a rule is likely to be expensive and could substantially impact the commercial airlines. In return, there is likely to be a reduction in the risk of commercial aviation accidents due to pilot fatigue.     

A risk-estimation methodological framework using quantitative assessment techniques and real accidents’ data: Application in an aluminum extrusion industry

The risk estimation presumably is the most crucial part of the entire procedure of assessing hazards/unsafe situations in the work, and especially in the industries’ and constructions’ worksites, where the working conditions are unstable. We can consider the risk as a quantity, which can be estimated and expressed by a mathematical relation, under the help of real accidents’ data. The aim of this work is quadruplicate: (a) the development, elaboration and explanation of two new quantitative risk-assessment techniques, (b) the improvement of specific points of other scientific works, as far as concerns quantitative risk estimation, (c) the application of these techniques on an industrial productive procedure (as a case study) and (d) the comparison of their outcome risk-estimation results. Particularly, we develop and analyze the theoretical background of the two techniques, which we call as “proportional technique” and “decision matrix technique”, and apply them on an aluminum extrusion industry's worksite, which is situated in Greece, by using real data of potential sources of hazards, recorded by safety managers, during the 5.5-year time period of 1999–2004. Comparing the results of the two quantitative risk-assessment techniques, we infer that they are compatible. Therefore, the most important hazard source in the aluminum industry is the “squeezing and hits by dropping objects (transported by derricks)”, and imposes that immediate suppressive measures must be taken place to abolish the danger source.     

What is most important for safety climate: The company belonging or the local working environment? – A study from the Norwegian offshore industry

Obtaining knowledge about factors affecting health, safety and environment (HSE) is of major interest to the petroleum industry, but there is currently a severe shortage of relevant studies. The aim of this study was to examine the relative influence of offshore installation (local working environment) and company belonging on employees’ opinions concerning occupational health and safety. We analyzed data from a safety climate survey answered by 4479 Norwegian offshore petroleum employees in 2005 on the dimensions “Safety prioritisation”, “Safety management and involvement”, “Safety versus production”, “Individual motivation”, “System comprehension” and “Competence” using one way analysis of variance (ANOVA), effect size and mixed model. The companies differed significantly for “Safety prioritisation”, “Safety versus production”, “Individual motivation”, “System comprehension” and “Competence”. The local offshore installation explained more of the safety climate than the company they were employed in or worked for did.     

改进的DEMATEL法在航空公司外委维修安全风险分析中的应用

为有效识别和分析外委维修安全风险因素间复杂的影响关系,提出了群决策DEMATEL分析方法。该方法以语言变量和三角模糊数之间的转换为基础,通过群决策理论集结专家信息建立直接影响矩阵;利用DEMATEL分析法对外委维修的安全风险因素进行辨识,实现定性定量相结合的分析。以某航空公司为例,采用该方法分析了14个对外委维修安全影响显著的风险因素。结果表明,在外委维修过程中,航空公司和承修商应重点监控7个原因型因素和中心度排序靠前的6个因素。     

A summary and synthesis of procedural regulations and standards—Informing a procedures writer's guide

Well-written procedures are an integral part of any industrial organization for safe operation, managing risks, and continuous improvement. Regulatory bodies around the world require industries to have current, accurate, and appropriate procedures for most processes. Although the importance of procedures is recognized by all industries in general, significant incidents still occur due to procedural breakdowns. Some of the procedural breakdowns come from obvious problems such as the procedure not being available or the procedure being wrong. However, some incidents have occurred when correct procedures were available and the operator used those procedures. In these instances, the reason workers do not follow procedures correctly may be attributable the procedure being presented or designed in a manner that does not sufficiently communicate the information in a manner that is easily and quickly understood. This indicates that procedure writers may need more guidance on how to write and design procedures so they accomplish this. To effectively manage risk, procedures need to be technically correct (and regulatory compliant) and usable. As part of this, the current work is focused on developing a systematic approach to a procedure writer's guide that includes a regulatory compliant component. The work presented here consists of an effort to identify procedure-writing practices necessary to ensure regulatory compliance by summarizing a large sample of regulations and standards from several industries. The regulations and standards were organized to reflect common ideas and the implications in terms of human factors needs for procedure design were identified. This information will be used as part of the development of a writer's guide that accounts for human factors (HF) that includes explanations of HF implications and empirical support for each of the guidelines. The novelty of the method and information presented here is in the idea of leveraging the cumulative information available regarding procedures in regulations and standards. Incorporating this information into a procedure's writers guide in this manner may not only facilitate procedure being regulatory compliant for facilities in different geographies of the world, but could also support their being written with considerations for human performance.