Verification of context-free timed systems using linear hybrid observers

  • Ahmed Bouajjani
  • Rachid Echahed
  • Riadh Robbana
Hybrid Systems
Part of the Lecture Notes in Computer Science book series (LNCS, volume 818)


We address the verification problem of infinite timed systems. We consider context-free timed systems defined as a generalization of the (regular) timed graphs [ACD90]. Then, we propose decision procedures for the verification of invariance properties of these systems, expressed by means of observation variables. These variables record relevant informations about the computations of the observed system. They are permanently updated along these computations without any interference with the behaviour of the system. Observation variables are either additional clocks (timers), nonbounded integer variables (accumulators), or constant slope continuous (real valued) variables (integrators).


Hybrid System Invariance Property Region Graph Integration Constraint Derivation Rule 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1994

Authors and Affiliations

  • Ahmed Bouajjani
    • 1
  • Rachid Echahed
    • 2
  • Riadh Robbana
    • 1
  1. 1.VERIMAG-SPECTREMontbonnot St-MartinFrance
  2. 2.LGI-IMAGGrenoble cedexFrance

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