5.2 Combinatorial Algorithm
The combinatorial approach aims to successfully “turn off” the disconnected or isolated dependent components (when the corresponding trigger component fails or becomes unavailable) so that they could not contribute to the system UF probability. The approach involves four tasks that, respectively, address UFs of independent trigger components of FDEP, transform the system with FDEP into subsystems without FDEPs, evaluate resultant subsystems, and integrate for the final system unreliability.
5.2.1 Task 1: Addressing UFs of Independent Trigger Components
Based on the simple and efficient algorithm (SEA) (Section 3.3.2), particularly (3.4), the system unreliability is evaluated as:

Pu,IT(t) in 5.1 is the probability that no independent trigger components undergo UFs, and Q(t) is the conditional system unreliability given that no independent trigger components...