Dependency among system elements impress the system performance and efficiency, thus dependencies have to be modeled and analyzed. The aim of this paper is introducing and studying a specified dependence in reliability analysis of fault trees with dynamic dependencies; named Timing Functional Dependency (TFDEP) gate. In most systems with functional dependency constructions equipped with known FDEP gate, event failures occur in particular order and their dependencies are only usual and sequentially without any time considerations. However, in some specific systems, the events in addition to the predefined order, are also time-dependent and for each occurrence, a specific event’s activation/deactivation time should be considered. This timing requirement necessitates inventing a new TFDEP gate. On the other hand, in order to exact simulation, the Fuzzy-bathtub distributions are used as the time-to-failure parameter and Fuzzy Monte Carlo technique throughout the predetermined operating time is considered to the simulation process. Finally, the proposed approach is implemented in an air/space system as an application example and the simulation results demonstrated that the presented technique is a valid approach in the analysis of system reliability with timing dependencies and events that have unknown failure occurrence probabilities.

系统元素之间的依赖关系会影响系统性能和效率，因此必须对依赖关系进行建模和分析。本文旨在介绍和研究具有动态依赖关系的故障树可靠性分析中的指定依赖关系；命名时序函数依赖 (TFDEP) 门。在大多数具有已知 FDEP 门的函数依赖结构的系统中，事件失败以特定的顺序发生，并且它们的依赖只是通常的和顺序的，没有任何时间考虑。但是，在某些特定系统中，除了预定义的顺序之外，事件也是时间相关的，对于每次发生，都应考虑特定事件的激活/停用时间。这种时序要求需要发明一种新的 TFDEP 门。另一方面，为了精确模拟，模糊浴缸分布用作故障时间参数，并且在整个预定操作时间内模糊蒙特卡罗技术被考虑到模拟过程中。最后，将所提出的方法作为应用示例在空/天系统中实施，仿真结果表明，所提出的技术是分析具有未知故障发生概率的时间依赖性和事件的系统可靠性的有效方法。