Observability of extended timed event graph (Q1883953)

The concepts of observability and reachability for extended timed event graphs are introduced and discussed in detail. Using graph theory, necessary and sufficient conditions for observability and reachability are formulated and proved. The standard structure of extended timed event graphs is also investigated using the concepts of observability and reachability. Moreover, many remarks, comments and relationships to results existing in the literature are given. Finally, it should be pointed out that discrete event systems are discussed in detail in the monograph [\textit{Chen Wende} and \textit{Qi Xiangdong}, The discrete event dynamic systems -- max algebra methods, Science Press, Beijing, China (1994)].