Activity list representation for a generalization of the resource-constrained project scheduling problem

0377-2217/$ see front matter 2008 Elsevier B.V. A doi:10.1016/j.ejor.2008.10.030 q This research was supported by NSERC grant (OGP * Corresponding author. Tel.: +1 514 343 5687; fax E-mail addresses: [email protected] umontreal.ca (J.A. Ferland). Most of the real life scheduling problems include several constraints in addition to the precedence and resource constraints considered in the resource-constrained project scheduling problem (RCPSP). In this paper, we define a generalization of the ðRCPSPÞwith a wide class of additional constraints, including (but not limited to): a pair of activities must be separated by at least a given duration; a subset of activities cannot be processed simultaneously; an activity cannot start before a particular period; an activity cannot be scheduled in a particular time window; there are resource constraints with varying required and available quantities. We show that for this generalization the activity list and the activity set list representations can be used as efficiently as in the ðRCPSPÞ and that by using these representations the optimal solution can always be reached. This allows most of the known solution procedures for ðRCPSPÞ based on these representations to be extended for the generalized ðRCPSPÞ by simply replacing the classical decoding procedure used for the ðRCPSPÞ with the generalized version introduced here. 2008 Elsevier B.V. All rights reserved.