标题： 一种用于在STPA中优先考虑不安全控制动作的结构化框架：eVTOL操作案例研究 显示英文标题

标题： A Structured Framework for Prioritizing Unsafe Control Actions in STPA: Case Study on eVTOL Operations

摘要： 系统理论过程分析（STPA）是一种广泛推荐的用于分析复杂系统安全的方法。 STPA可以根据分析的粒度和被分析系统的复杂性，识别出大量不安全的控制操作（UCAs）和需求。 管理大量的结果具有挑战性，尤其是在快速发展的开发生命周期中。 已经进行了大量研究以优化管理并优先处理STPA结果的效率。 然而，保持优先级的客观性以及传达优先的结果已成为常见的挑战。 在本文中，作者提出了一种补充方法，结合安全分析师和领域专家的输入，以更客观地优先处理UCAs。 这是通过评估每个UCA的严重性、发出UCA的每个控制器或决策者的影响力因素，以及根据不同因素评估UCA关键性的主题专家提供的排名来实现的。 此外，引入了蒙特卡洛模拟以减少主观性和相对性，从而实现对UCAs更客观的优先级排序。 作为更好地沟通优先级结果并规划系统开发下一步的手段，开发了一个动态缩放的优先级矩阵，以捕捉不同的一组优先UCAs。 该方法应用于一个实际项目，以提高电动垂直起降（eVTOL）的安全操作。 结果突出了需要优先考虑的关键UCAs，以实现更安全的eVTOL操作。 总共识别出318个UCAs。 根据优先级方法的应用，110个被认定为高优先级的UCAs，以加强系统设计。 显示英文摘要

摘要： Systems Theoretic Process Analysis (STPA) is a widely recommended method for analysing complex system safety. STPA can identify numerous Unsafe Control Actions (UCAs) and requirements depending on the level of granularity of the analysis and the complexity of the system being analysed. Managing numerous results is challenging, especially during a fast-paced development lifecycle. Extensive research has been done to optimize the efficiency of managing and prioritising the STPA results. However, maintaining the objectivity of prioritisation and communicating the prioritised results have become common challenges. In this paper, the authors present a complementary approach that incorporates inputs from both the safety analysts and domain experts to more objectively prioritise UCAs. This is done by evaluating the severity of each UCA, the impact factor of each controller or decision maker that issues the UCA, and the ranking provided by the subject matter experts who assess the UCA criticalities based on different factors. In addition, a Monte Carlo simulation is introduced to reduce subjectivity and relativity, thus enabling more objective prioritisation of the UCAs. As part of the approach to better communicate the prioritisation results and plan the next steps of system development, a dynamic-scaling prioritisation matrix was developed to capture different sets of prioritised UCAs. The approach was applied to a real project to improve the safe operations of Electric Vertical Take-off and Landing (eVTOL). The results highlighted critical UCAs that need to be prioritised for safer eVTOL operation. 318 UCAs were identified in total. Based on the application of the prioritisation methodology, 110 were recognized as high-priority UCAs to strengthen the system design.