{"type":"ScholarlyArticle","title":"A Theoretical and Experimental Comparison of Constraint Propagation Techniques for Disjunctive Scheduling","authors":[{"name":"Philippe Baptiste","slug":"philippe-baptiste","given":"Philippe","family":"Baptiste","affiliation":""},{"name":"Claude Le Pape","slug":"claude-le-pape","given":"Claude","family":"Le Pape","affiliation":""}],"abstract":"Di sjun ct ive cons tr aints are widely used to ensure that th e tim e int ervals ov er which two activit ies require th e sam e resource c annot overlap: if a resource is required by two activities A and B , th e disjun ctive constraint st ates that eith er A precedes B or B precedes A . Th e \"propagat ion\" of disjunctive constraints consists in dete rmining cas es where only one of the two orderings is feasibl e. It results in updating the tim e -bounds of the two activities. The standard algorithm for propagating disjunctive const raints achieves arc-H -consistency. Two types of m e th ods that provide mor e precise tim ebounds are studi ed and compar ed . The first typ e of me thod consists in determining whether an activity A must , can , or cannot be the first or th e last to exe cut e among a set of activities that require th e same resource. The second consists in comparing the amount of \"resource energy\" required ov er a time int erval [t1 t2) to th e a mount of energy that is available over the same int erval. Th e main result of the study is an impleme ntation of th e first me thod in ILOG Sc HEDULE , a generic tool for constraint-based sc heduling whi ch exhibits performan ce in the sam e range of e ffici ency as specific operations research algorithms .","doi":null,"url":"https://ijcai.org/proceedings/1995/79","pdf":"https://ijcai.org/proceedings/1995/0079.pdf","markdown":"https://ijcai.org/proceedings/1995/79.md","bibtex":"https://ijcai.org/proceedings/1995/bibtex/79","volume":{"slug":"1995","title":"Proceedings of the Fourteenth International Joint Conference on Artificial Intelligence","short_title":"IJCAI 1995","url":"https://ijcai.org/proceedings/1995/","year":1995,"location":"Montréal, Québec, Canada","dates":"","editors":"Chris S. Mellish","isbn":"","publisher":"International Joint Conferences on Artificial Intelligence","doi_prefix":""},"section":"Constraint Satisfaction","track":"Constraint Satisfaction","number":79,"pages":{"first":600,"last":605},"keywords":[],"videos":[],"references":[],"license_note":"Copyright International Joint Conferences on Artificial Intelligence."}