A Calculus for Timed Automata

A language for representing timed automata is introduced. Its semantics is defined in terms of timed automata. This language is complete in the sense that any timed automaton can be represented by a term in the language. We also define a direct operational semantics for the language in terms of (timed) transition systems. This is proven to be equivalent (or, more precisely, timed bisimilar) to the interpretation in terms of timed automata. In addition, a set of axioms is given that is shown to be sound for timed bisimulation. Finally, we introduce several features like hiding operator, the parallel composition and derived time operations like wait, time-out and urgency. We conclude with an example and show that we can eliminate non-reachable states using algebraic techniques. 1991 Mathematics Subject Classification: 68Q45, 68Q55, 68Q60. 1991 CR Categories: D.3.1, F.3.1, F.3.2, F.4.3. Keywords: process algebra, real time, timed automata, timed transition system. Note: An extended abs..

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