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New strategies for stochastic resource-constrained project scheduling

Authors:
Salim Rostami at KU Leuven
Salim Rostami
Stefan Creemers at IESEG School of Management
Stefan Creemers
Roel Leus at KU Leuven
Roel Leus
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We study the stochastic resource-constrained project scheduling problem or SRCPSP, where project activities have stochastic durations. A solution is a scheduling policy, and we propose a new class of policies that is a generalization of most of the classes described in the literature. A policy in this new class makes a number of a-priori decisions in a preprocessing phase while the remaining scheduling decisions are made online. A two-phase local search algorithm is proposed to optimize within the class. Our computational results show that the algorithm has been efficiently tuned towards finding high-quality solutions, and that it outperforms all existing algorithms for large instances. The results also indicate that the optimality gap even within the larger class of elementary policies is very small.
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... Therefore, existing research on the stochastic RCPSP mainly considers uncertain activity duration. In different studies, scholars have tried to use different probability distributions to describe the uncertainty of activity duration, such as exponential distribution [8][9][10][11][12][13][14][15], beta distribution [9][10][11]16], uniform distribution [8][9][10][11]16], triangular distribution [17], normal distributions [18], etc. Among them, triangular distribution has gained particular prominence in practice due to its intuitive three-parameter structure (minimum, mode, maximum) that directly corresponds to the three-point estimation technique (optimistic, most likely, pessimistic) commonly employed by project managers. ...
... Therefore, existing research on the stochastic RCPSP mainly considers uncertain activity duration. In different studies, scholars have tried to use different probability distributions to describe the uncertainty of activity duration, such as exponential distribution [8][9][10][11][12][13][14][15], beta distribution [9][10][11]16], uniform distribution [8][9][10][11]16], triangular distribution [17], normal distributions [18], etc. Among them, triangular distribution has gained particular prominence in practice due to its intuitive three-parameter structure (minimum, mode, maximum) that directly corresponds to the three-point estimation technique (optimistic, most likely, pessimistic) commonly employed by project managers. ...
... Therefore, existing research on the stochastic RCPSP mainly considers uncertain activity duration. In different studies, scholars have tried to use different probability distributions to describe the uncertainty of activity duration, such as exponential distribution [8][9][10][11][12][13][14][15], beta distribution [9][10][11]16], uniform distribution [8][9][10][11]16], triangular distribution [17], normal distributions [18], etc. Among them, triangular distribution has gained particular prominence in practice due to its intuitive three-parameter structure (minimum, mode, maximum) that directly corresponds to the three-point estimation technique (optimistic, most likely, pessimistic) commonly employed by project managers. ...
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