# The theory of timed automata

Conference paper

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## Abstract

We propose *timed automata* to model the behavior of real-time systems over time. Our definition provides a simple, and yet powerful, way to annotate state-transition graphs with timing constraints using finitely many real-valued *clocks*. A timed automaton accepts *timed words* — strings in which a real-valued time of occurrence is associated with each symbol. We study timed automata from the perspective of formal language theory: we consider closure properties, decision problems, and subclasses. We discuss the application of this theory to automatic verification of real-time requirements of finite-state systems.

## Keywords

Real-time systems Automatic verification Formal languages Automata theory## Preview

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© Springer-Verlag Berlin Heidelberg 1992