Abstract
•Bi-component system with overlapping rescue procedures is considered.•Components are affected by common shocks during the joint rescue.•The rescue process slows down when both components are rescued simultaneously.•Probabilistic framework is developed to derive the normalized expected losses.•The mission abort policy minimizing expected losses is suggested.
Redundant systems are widely employed to mitigate the risk of mission failure. Existing models typically assume independent recovery actions and dedicated rescue resources for each component following a mission abort. This paper contributes by addressing a more realistic class of systems with two components whose rescue procedures (RPs) may overlap and compete for common rescue resource, creating new dependencies between mission continuation and component survival. Individual shocks impacting a single component during its operation and common shocks impacting both components during overlapped RPs are addressed. A mission abort policy (MAP), defined by shock counts and task execution time, is modeled. A probabilistic framework is developed to derive the mission success probability, expected cost of component losses, and normalized expected damage (NED), explicitly capturing interactions among mission continuation, RP execution, and resource contention. An optimization problem is formulated to identify the MAP that minimizes NED. A case study of a two-version programming infrastructure control system illustrates the model and reveals the effects of task beginning time, component loss cost, RP slowdown factor due to resource contention, and shock rates on mission performance and optimal MAPs. The results provide managerial insights for balancing risks of mission failure and system loss.