Nonbinary Constraint Satisfaction: From the Dual to the Primal

Nonbinaryconstraints haverecently beenstudiedquite extensivelysincethey representreal life problemsverynaturally. Specifically,extensionsto binaryarc consistencyinto generalised arc consistency(GAC),and forwardchecking that incorporates a limited amountof GAChavebeenproposed, to handlenon-binaryconstraints directly. Enforcing arc consistencyon the dual encodinghas beenshown to strictly dominateenforcingGAConthe primalencoding. Morerecently,modificationsto dualarc consistencyhaveextendedtheseresults to dualencodingsthat are basedonthe constructionof compactconstraintcoverings,that retain the completenessof the encodings,whileusinga fraction of the space.In this paperwepresentresults that combinethe enforcementof arc consistencyin thesecoveringbaseddualencodings,with performingforwardcheckingbasedsearchin the primal encoding.Wedemonstratehowthis newscheme canbe shownto strictly dominatestandardnon-binaryforwardchecking,whilebeingable to efficiently enforceextremelyhighlevels of consiste...

• Type: Conference
• Year: 2001
• Where: FLAIRS
• Authors: Sivakumar Nagarajan, Scott D. Goodwin, Abdul Sattar
• Keywords: Artificial Intelligence, Dual Encodinghas, Enforcementof Arc, FLAIRS 2001, Specifically