Design and Analysis of a Failsafe Algorithm for Solving Boolean Equations

  • Harvey E. Rhody
  • Vittorio Manoni
  • James R. Hoelscher
Conference paper


Since the installation of the first mechanical interlocking in 1856, railway signal engineers have developed a set of rules which define the essential requirements for safe train movement. In the majority of cases this set of rules can be expressed as a closed set of boolean equations which, when implemented as written, yield a safe operating system. The boolean equation set will vary depending upon the particular requirements of each application. The set of general rules are imposed on the specific requirements of each application to yield a closed set of boolean equations which completely describe the safety and operational requirements of that application.


Product Term Boolean Expression Linear Feedback Shift Register Independent Agent Boolean Equation 
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 London Limited 1993

Authors and Affiliations

  • Harvey E. Rhody
    • 1
  • Vittorio Manoni
    • 2
  • James R. Hoelscher
    • 3
  1. 1.RIT Research Corporation Rochester Institute of Technology RochesterNYUSA
  2. 2.SASIB Signalamento FerroviarioBolognaItaly
  3. 3.General Railway Signal Corporation RochesterNYUSA

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