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Abstract

We present an algorithm for finding the minimal number of clocks of a given timed automaton recognizing the language described by a so-called bounded timed regular expressionw. This algorithm is based on the partition of the timed projection of w into so-called delay cells. Using this decomposition, we give a method to compute practically this number for w. We then apply this technique to prove that for some n-clock timed automation we need an additional clock to encode urgency.

Keywords

Timed automaton timed regular expression minimal number of clocks n-clock timed language urgency 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Michaël Adélaïde
    • 1
  • Claire Pagetti
    • 1
  1. 1.Labri (UMR 5800), Domaine UniversitaireTalenceFrance

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