Expresivity of Timed Discrete Event Systems and Timed Automata

In control engineering and computer science, different formalisms are used for the specification and subsequent analysis of timed extensions of discrete event systems. In this paper, the expressivity of timed discrete event systems and that of timed automata are compared for the purpose of modeling of discrete event systems involving time aspects. A behavior-preserving transformation from timed discrete event systems to timed automata is provided, and it is shown that a similar transformation from timed automata to timed discrete event systems is not possible under the assumption that the event sets of the system modeled remains the same.