New valid inequalities for the symmetric vehicle routing problem with simultaneous pickup and deliveries
Research & Publications
New valid inequalities for the symmetric vehicle routing problem with simultaneous pickup and deliveries
27/11/2022
New valid inequalities for the symmetric vehicle routing problem with simultaneous pickup and deliveries
Yogesh Kumar Agarwal and Prahalad Venkateshan
Journal Articles | Networks
The symmetric vehicle routing problem with simultaneous pickup and deliveries is considered. The current state-of-the-art method to solve this problem employs the idea of a no-good cut. This article achieves an order of magnitude improvement in the computational time needed to solve difficult problem instances by generalizing the no-good cuts and developing a way to generate improved no-good cuts much earlier in a branch-and-bound tree. Results are reported on benchmark instances in literature and new difficult instances generated by the authors. Some polyhedral results are presented about the strength of the generalized no-good cuts for a special case of the problem.