# SEMIDEFINITE RELAXATIONS FOR THE SCHEDULING NUCLEAR OUTAGES PROBLEM

### Abdel Lisser, Agnes Gorge, Riadh Zorgati

#### Abstract

We investigate semidefinite relaxations for solving aMIQP (Mixed-Integer Quadratic Program) formulation of the scheduling of nuclear power plants outages, which is extremely hard to solve with CPLEX. Based on our numerical experiments, results obtained with semidefinite relaxations improve those obtained with continuous relaxation: the gap between the optimal solution and the continuous relaxation is on average equal to 1.80% whereas the semidefinite relaxation yields an average gap of 1.56\%. These bounds are then used to obtain a feasible solution with a randomized rounding procedure.

#### References

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#### Paper Citation

#### in Harvard Style

Lisser A., Gorge A. and Zorgati R. (2012). **SEMIDEFINITE RELAXATIONS FOR THE SCHEDULING NUCLEAR OUTAGES PROBLEM** . In *Proceedings of the 1st International Conference on Operations Research and Enterprise Systems - Volume 1: ICORES,* ISBN 978-989-8425-97-3, pages 386-391. DOI: 10.5220/0003743203860391

#### in Bibtex Style

@conference{icores12,

author={Abdel Lisser and Agnes Gorge and Riadh Zorgati},

title={SEMIDEFINITE RELAXATIONS FOR THE SCHEDULING NUCLEAR OUTAGES PROBLEM},

booktitle={Proceedings of the 1st International Conference on Operations Research and Enterprise Systems - Volume 1: ICORES,},

year={2012},

pages={386-391},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0003743203860391},

isbn={978-989-8425-97-3},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 1st International Conference on Operations Research and Enterprise Systems - Volume 1: ICORES,

TI - SEMIDEFINITE RELAXATIONS FOR THE SCHEDULING NUCLEAR OUTAGES PROBLEM

SN - 978-989-8425-97-3

AU - Lisser A.

AU - Gorge A.

AU - Zorgati R.

PY - 2012

SP - 386

EP - 391

DO - 10.5220/0003743203860391