Zhao Xian, Chai Xiaofei, Sun Jinglei, Qiu Qingan
School of Management and Economics, Beijing Institute of Technology, Beijing, China.
Risk Anal. 2022 Dec;42(12):2823-2834. doi: 10.1111/risa.13869. Epub 2022 Jan 15.
For safety-critical systems such as aircrafts and submarines, mission abort is commonly deployed to enhance system survivability at the cost of reducing mission success probability. In addition to mission abort, protective device can also mitigate the failure risk of safety-critical systems by reducing the magnitude of external shocks. Considering the effect of protective device on system failure behavior, this article proposes a condition-based mission abort policy where a mission is terminated and rescue procedure starts immediately if the state of system is worse than a control limit. Based on the developed mission abort policy, mission reliability and system survivability are evaluated to analyze the risk of mission failure and system failure. The optimal mission abort threshold balancing the tradeoff between mission reliability and system survivability is investigated. Furthermore, the joint optimization of mission abort and protective device selection policies is explored by simultaneously optimizing the defensive factor and abort threshold. A numerical example on a hydraulic system is presented to illustrate the applicability of the proposed policies.
对于飞机和潜艇等安全关键系统，通常采用任务中止来提高系统生存能力，但代价是降低任务成功概率。除了任务中止外，保护装置还可以通过降低外部冲击的强度来减轻安全关键系统的故障风险。考虑到保护装置对系统故障行为的影响，本文提出了一种基于状态的任务中止策略，即如果系统状态比控制极限差，则立即终止任务并启动救援程序。基于所制定的任务中止策略，评估任务可靠性和系统生存能力，以分析任务失败和系统故障的风险。研究了平衡任务可靠性和系统生存能力之间权衡的最优任务中止阈值。此外，通过同时优化防御因子和中止阈值，探索了任务中止和保护装置选择策略的联合优化。给出了一个液压系统的数值例子来说明所提策略的适用性。
