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Mardi 18 Octobre
| Heure: |
12:30 - 13:30 |
| Lieu: |
Salle B107, bâtiment B, Université de Villetaneuse |
| Résumé: |
Lower bounds in resource constrained shortest path algorithms |
| Description: |
Axel Parmentier Resource constrained shortest path problems arise naturally as pricing sub-problems of column generation approaches to a wide range of routing and scheduling problems. The algorithms for these problems rely on dominance relations between paths to discard partial solutions in an enumeration of all the paths. It is well known that the use of bounds on paths resources in addition to dominance relations strongly accelerates these algorithms. Nonetheless, there is still no standard procedure to build such bounds in non-linear or stochastic settings. We provide such a bounding procedure and sho w its efficiency on several deterministic and stochastic path problems. Besides, enumeration algorithms exhibit poor performances when the number of constraints increases. We show that using sets of bounds instead of single bounds enable to discard more paths and thus to tackle better with these difficult instances. Finally, we prove the relevance of these procedures in the context of column generation on industrial instances of the airline crew pairing problem. |
| Heure: |
14:00 - 17:00 |
| Lieu: |
Salle B107, bâtiment B, Université de Villetaneuse |
| Résumé: |
Combinatoire des mots |
| Description: |
Johan Nilsson |
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