Diagnosis of Patterns in Partially-Observed Discrete-Event Systems

This paper studies the problem of diagnosis of a pattern in a partially-observed discrete-event system. Two different types of pattern diagnosability are defined in the context of formal languages: (i) S-type for patterns in the form of subsequences of sequences of events and (ii) T-type for patterns in the form of substrings of sequences of events. These two notions of pattern diagnosability generalize the notion of diagnosability of single events in prior works. Implementable necessary and sufficient conditions for both types of pattern diagnosability in systems modeled by regular languages are presented