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Alternative subgraphs

RCPSP with alternatives

In most real-life projects, there exist alternative ways to execute work packages in the project structure due to the ever-increasing complexity and uncertainty in the project environment. Scheduling projects with alternative project structures is a challenging task as the problem consists of two subproblems: the selection subproblem and the scheduling subproblem. In order to support this novel field of research, the Operations Research and Scheduling group has developed an extension of the RCPSP, the so-called RCPSP with alternative subgraphs (RCPSP-AS). The research objective is to propose an unambiguous definition of alternative subgraphs and a comprehensive classification of the different types of alternative subgraphs. Based on the proposed problem definition, we develop a large-scale dataset of artificial project instances to support computational experiments. This research effort allows to quantify the impact of alternatives in the project structure, obtain managerial insights and foster future efforts in this challenging field of research.

References :

  • Servranckx, T., and Vanhoucke, M., 2018, "A tabu search procedure for the resource-constrained project scheduling problem with alternative subgraphs", European Journal of Operational Research, 273(3), 841–860. Download the data from this paper here.
  • Servranckx, T., and Vanhoucke, M., 2019, “Strategies for project scheduling with alternative subgraphs under uncertainty: similar and dissimilar sets of schedules”, European Journal of Operational Research, 279(1), 38-53.
  • Servranckx, T., Vanhoucke, M., and Vanhouwaert, G., 2020, “Analysing the impact of alternative network structures on resource-constrained schedules: Artificial and empirical experiments”, Computers and Industrial Engineering, 148, 106706. Download the project cards of the case studies here and the additional results of the analysis here.