Chen ZuXi, Lin HongKai, Mei Meng, Zhu YongHua, Wang XiaoYong, Xu ZhongWei, Luo XiangYu
College of Computer Science and Technology, Huaqiao University, No.668 Jimei Avenue, Xiamen, 361021, Fujian, China.
College of Electronic and Information Engineering, Tongji University, No.4800 Caoan Road, Jiading, 201804, Shanghai, China.
Heliyon. 2024 May 24;10(11):e31776. doi: 10.1016/j.heliyon.2024.e31776. eCollection 2024 Jun 15.
Safety-critical systems, such as the railway signal system, are subject to potentially high costs from failures, including loss of life and property damage. The use of new technology, including communication-based train control (CBTC) systems with software and computers, has changed the types of accidents that occur. Software-related issues and dysfunctional interactions between system components controlled by the software are increasingly the cause of incidents. Developing a "safe" safety-critical system requires accurate and complete safety requirements, which are the foundation of system development. Traditional hazard analysis techniques are insufficient for identifying the causes of accidents in modern railway signaling systems. Systems-Theoretic Process Analysis (STPA) is a powerful new hazard analysis method designed to address these limitations. Building upon this foundation, a hierarchical approach to safety requirement development has been further developed. This approach combines STPA analysis with a hierarchical modeling approach to establish traceability links from safety requirements to specific architectures, refine and allocate system-level safety requirements to relevant subsystems, and abstract safety requirements at higher hierarchical levels to enable easy changes to lower-level implementations. This paper employs the aforementioned methodology within the context of the CBTC system, thereby enhancing risk management and hazard analysis, enabling early insights, and facilitating the generation of safety requirements of CBTC System.
安全关键系统，如铁路信号系统，一旦发生故障可能会导致高昂的成本，包括人员伤亡和财产损失。新技术的应用，包括带有软件和计算机的基于通信的列车控制（CBTC）系统，已经改变了事故发生的类型。与软件相关的问题以及由软件控制的系统组件之间的功能失调交互越来越成为事故的原因。开发一个“安全的”安全关键系统需要准确而完整的安全要求，这是系统开发的基础。传统的危害分析技术不足以识别现代铁路信号系统中的事故原因。系统理论过程分析（STPA）是一种强大的新危害分析方法，旨在解决这些局限性。在此基础上，进一步开发了一种分层的安全要求开发方法。这种方法将STPA分析与分层建模方法相结合，以建立从安全要求到特定架构的可追溯性链接，将系统级安全要求细化并分配给相关子系统，并在更高层次上抽象安全要求，以便能够轻松更改较低层次的实现。本文在CBTC系统的背景下采用上述方法，从而加强风险管理和危害分析，实现早期洞察，并促进CBTC系统安全要求的生成。
