| Titre : | Integrated sequencing and scheduling in coil coating (2011) |
| Auteurs : | Wiebke Höhn, Auteur ; Felix G. König, Auteur ; Rolf H. Möhring, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | Management science (Vol. 57 N° 4, Avril 2011) |
| Article en page(s) : | pp. 647-666 |
| Note générale : | Management |
| Langues : | Anglais |
| Index. décimale : | 658 (Organisation des entreprises. Techniques du commerce) |
| Tags : | Sequencing Scheduling Integrated steel production Coil coating 2-union graphs Independent set Branch-and-price |
| Résumé : | We consider a complex planning problem in integrated steel production. A sequence of coils of sheet metal needs to be color coated in consecutive stages. Different coil geometries and changes of colors necessitate time-consuming setup work. In most coating stages one can choose between two parallel color tanks. This can either reduce the number of setups needed or enable setups concurrent with production. A production plan comprises the sequencing of coils and the scheduling of color tanks and setup work. The aim is to minimize the makespan for a given set of coils. We present an optimization model for this integrated sequencing and scheduling problem. A core component is a graph theoretical model for concurrent setup scheduling. It is instrumental for building a fast heuristic that is embedded into a genetic algorithm to solve the sequencing problem. The quality of our solutions is evaluated via an integer program based on a combinatorial relaxation, showing that our solutions are within 10% of the optimum. Our algorithm is implemented at Salzgitter Flachstahl GmbH, a major German steel producer. This has led to an average reduction in makespan by over 13% and has greatly exceeded expectations. |
| DEWEY : | 658 |
| ISSN : | 0025-1909 |
| En ligne : | http://mansci.journal.informs.org/cgi/content/abstract/57/4/647 |
