Use of Imprecise Computation to Enhance Dependability of Real-Time Systems

  • Jane W. S. Liu
  • Kwei-Jay Lin
  • Riccardo Bettati
  • David Hull
  • Albert Yu
Part of the The Springer International Series in Engineering and Computer Science book series (SECS, volume 284)


In a system based on the imprecise-computation technique, each time-critical task is designed in such a way that it can produce a usable, approximate result in time whenever a failure or overload prevents it from producing the desired, precise result. This section describes ways to use this technique together with traditional fault-tolerance methods to reduce the costs of providing fault tolerance and enhanced availability. Specifically, an imprecise mechanism for the generation and use of approximate results can be integrated in a natural way with traditional checkpointing and replication mechanisms. Algorithms and process structures for this integration and rules for determining when approximate results can be used in place of the desired results are discussed.


Processor Time Recovery Action Approximate Result Modify Algorithm Repair Server 
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

© Kluwer Academic Publishers 1994

Authors and Affiliations

  • Jane W. S. Liu
    • 1
  • Kwei-Jay Lin
    • 2
  • Riccardo Bettati
    • 1
  • David Hull
    • 1
  • Albert Yu
    • 3
  1. 1.the Department of Computer ScienceUniversity of Illinois at Urbana-ChampaignUrbana
  2. 2.the Department of Electrical and Computer EngineeringUniversity of California, IrvineIrvine
  3. 3.Hughes AircraftRadar Systems GroupLos Angeles

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