Optimal Sequencing of Contract Algorithms

  • Shlomo Zilberstein
  • François Charpillet
  • Philippe Chassaing


We address the problem of building an interruptible real-time system using non-interruptible components. Some artificial intelligence techniques offer a tradeoff between computation time and quality of results, but their run-time must be determined when they are activated. These techniques, called contract algorithms, introduce a complex scheduling problem when there is uncertainty about the amount of time available for problem-solving. We show how to optimally sequence contract algorithms to create the best possible interruptible system with or without stochastic information about the deadline. These results extend the foundation of real-time problem-solving and provide useful guidance for embedding contract algorithms in applications.

contract algorithms flexible computation real-time problem solving mathematical foundation meta-level control 


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Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • Shlomo Zilberstein
    • 1
  • François Charpillet
    • 2
  • Philippe Chassaing
    • 3
  1. 1.Department of Computer ScienceUniversity of MassachusettsAmherstUSA
  2. 2.LORIA-INRIAVandoeuvre-lès-Nancy CedexFrance
  3. 3.Institut de Mathématiques Elie CartanUniversité Henri Poincaré Nancy IVandoeuvre-lès-Nancy CedexFrance

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