Wednesday, 16:15 - 16:40 h, Room: H 0106


Guvenc Sahin
Tactical and strategic crew planning problems in railways

Coauthors: Fardin Dashty Saridarq, A. Çetin Suyabatmaz


We consider the tactical level planning problem in railways that determine the minimum sufficient crew resources level for one crew region at a time given the list of periodic train duties in a finite planning horizon. We formulate this problem once as a network flow problem and once as a set covering problem. The set covering version may only be attacked with a column-and-row generation algorithm, and the experimental results are not satisfactory from a computational point of view when compared to the network flow formulation. Even with complicating hard constraints that challenge the network flow formulation, the set covering problem is not easy to handle while the network flow formulations conveys optimal solutions with no additional effort. We also extend the network flow formulation to consider multiple regions simultaneously while the allocation of train duties among the regions is partially unknown. The problem is to determine the allocation and the level of minimum sufficient crew resources level coherently. The network flow formulation still provides satisfactory results, but only for a limited number of regions under consideration.


Talk 3 of the contributed session Wed.3.H 0106
"Vehicle and crew planning" [...]
Cluster 13
"Logistics, traffic, and transportation" [...]


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