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Propagation Redundancy in Redundant Modelling

  • Chiu Wo Choi
  • Jimmy Ho Man Lee
  • Peter J. Stuckey
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2833)

Abstract

Combining mutually redundant models with channelling constraints increases constraint propagation. However, the extra computation efforts of the additional variables and constraints may outweigh the gain of reduction in search space. In fact, many of the constraints in redundant modelling are not only logically redundant but also propagation redundant and hence cannot further reduce search space. We give general theorems for proving propagation redundancy of one constraint with respect to channelling constraints and constraints in the other model. We define a broad form of channelling constraints that are covered by our approach. We illustrate, using problems from CSPLib (http://www.csplib.org/), how detecting and removing propagation redundant constraints can significantly speed up solving behaviour.

Keywords

Channel Function Integer Variable Propagation Redundancy Redundant Constraint Interval Constraint 
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 2003

Authors and Affiliations

  • Chiu Wo Choi
    • 1
  • Jimmy Ho Man Lee
    • 1
  • Peter J. Stuckey
    • 2
  1. 1.Department of Computer Science and EngineeringThe Chinese University of Hong KongShatin, N.T., Hong Kong SARChina
  2. 2.Deptartment of Computer Science & Software EngineeringUniversity of MelbourneAustralia

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