6.3 Decision Diagram–Based Aggregation Method
The EDA approach discussed in Section 6.2 involves generating and solving a number of reduced reliability problems separately (and possibly in parallel if adequate computing resources are available). Very often, reliability models of the reduced problems can share common submodels, which are stored and evaluated multiple times. To improve computational efficiency and reduce storage requirements, an enhanced decision diagram (DD)‐based analysis method is discussed in this section, where a single compact system DD is generated to model all the reduced problems sharing their isomorphic sub‐DDs, implementing an automatic aggregation process of the original EDA approach .
6.3.1 Three‐Step Method
The DD‐based aggregation approach can be conducted in the following three steps:
- Step 1: Conduct CCF modeling. Given that m elementary causes CCi exist in the system, a CCE space is first built based on the statistical...