# A determinizable class of timed automata

## Abstract

We introduce the class of *event- recording timed automata* (ERA). An event-recording automaton contains, for every event *a*, a clock that records the time of the last occurrence of *a.* The class ERA is, on one hand, expressive enough to model (finite) timed transition systems and, on the other hand, determinizable and closed under all boolean operations. As a result, the language inclusion problem is decidable for event-recording automata. We present a translation from timed transition systems to event-recording automata, which leads to an algorithm for checking if two timed transition systems have the same set of timed behaviors.

We also consider *event-predicting timed automata* (EPA), which contain clocks that predict the time of the next occurrence of an event. The class of *event-clock automata* (ECA), which contain both event-recording and event-predicting clocks, is a suitable specification language for real-time properties. We provide an algorithm for checking if a timed automaton meets a specification that is given as an event-clock automaton.

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