Enhancing the Inverse Method with State Merging

  • Étienne André
  • Laurent Fribourg
  • Romain Soulat
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7226)


Keeping the state space small is essential when verifying real-time systems using Timed Automata (TA). In the model-checker Uppaal, the merging operation has been used extensively in order to reduce the number of states. Actually, Uppaal’s merging technique applies within the more general setting of Parametric Timed Automata (PTA). The Inverse Method (IM) for a PTA \(\mathcal{A}\) is a procedure that synthesizes a zone around a given point π 0 (parameter valuation) over which \(\mathcal{A}\) is guaranteed to behave in an equivalent time-abstract manner. We show that the integration of merging into IM leads to the synthesis of larger zones around π 0. It also often improves the performance of IM, both in terms of computational space and time, as shown by our experimental results.


Inverse Method Reachability Graph Time Automaton Parameter Valuation Computational Space 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Étienne André
    • 1
  • Laurent Fribourg
    • 2
  • Romain Soulat
    • 2
  1. 1.LIPNCNRS UMR 7030, Université Paris 13France
  2. 2.LSVENS Cachan & CNRSFrance

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