Solving a time-indexed formulation for an unrelated parallel machine scheduling problem by preprocessing and cutting planes

Lotte Berghman (1) , Frits Spieksma (2) , Vincent t'Kindt (3)

1 UT - Université de Toulouse
2 ORSTAT - Operations Research and Business Statistics
3 LIFAT - Laboratoire d'Informatique Fondamentale et Appliquée de Tours

We consider a time-indexed formulation for the unrelated parallel machine scheduling problem. We show that all polyhedral knowledge known from the single machine problem (in particular, valid inequalities) is applicable to this formulation. We present new facet-inducing valid inequalities and a preprocessing technique involving fixing variables based on reduced costs. We combine both techniques in a basic cutting-plane algorithm and test the performance of the resulting algorithm by running it on randomly generated instances.

Mots clés: unrelated machine scheduling; time-indexed formulation; valid inequalities; cutting plane algorithm; variable fixing

Domaines: Recherche opérationnelle [math.OC]

Lotte Berghman, Frits Spieksma, Vincent t'Kindt. Solving a time-indexed formulation for an unrelated parallel machine scheduling problem by preprocessing and cutting planes. 2018. ⟨hal-01685395⟩