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Match-time predictability in real-time production systems

  • Franz Barachini
General Reasoning
Part of the Lecture Notes in Computer Science book series (LNCS, volume 462)

Abstract

A major obstacle to the widespread use of expert systems in real-time domains is the non-predictability of rule execution times. While some researchers have addressed the issue of optimizing response times through better algorithms or parallel hardware, there has been little research towards run-time guarantee for specific match algorithms.

A widely used algorithm for real-time production systems is the RETE algorithm. We want to achieve match-time predictability for RETE, because it is required for real-time responses. Despite RETE's exponential worst-case run-time behavior, I present a pragmatic solution of how to guarantee reaction within a suer-defined time-frame, even if the problem cannot be solved during that period. The solution is based on a micro-level reasoner working at a fine granularity and using on-line cost measures of individual nodes in the RETE network.

Keywords

Expert System Token Memory Truth Assignment Fine Granularity Knowledge Search 
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 1990

Authors and Affiliations

  • Franz Barachini
    • 1
  1. 1.Alcatel-Elin ForschungszentrumViennaAustria

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