In the double TSP with multiple stacks, one performs a Hamiltonian circuit to pick up n items, storing them in a vehicle with s stacks of finite capacity q satisfying lastin-first-out constraints, and then delivers every item by performing a Hamiltonian circuit. We introduce an integer linear programming formulation with arc and precedence variables. We show that the underlying polytope shares ...

The double travelling salesman problem with multiple stacks (DTSPMS) is a pickup and delivery problem in which all pickups must be completed before any deliveries can be made. The problem originates from a real-life application where a 40 foot container (configured as 3 columns of 11 rows) is used to transport up to 33 pallets from a set of pickup customers to a set of delivery customers. The p...

The new emerging area of Enterprise Wide Optimization (EWO) has focused the attention in effectively solving the combined producion/distribution scheduling problem. The importance of logistic activities performed in multi-site environments comes from the relative magnitude f the associated transportation costs and the good chance of getting large savings on such expenses. This paper first devel...

This paper introduces the pickup and delivery traveling salesman problem with handling costs (PDTSPH). In the PDTSPH, a single vehicle has to transport loads from origins to destinations. Loading and unloading of the vehicle is operated in a last-in-firstout (LIFO) fashion. However, if a load must be unloaded that was not loaded last, additional handling operations are allowed to unload and rel...

The split pickup and delivery problem is to find the shortest route that can provide delivery nodes with commodities collected from pickup nodes, subject to the vehicle load constraint. In particular, the split feature allows multiple visits to nodes and thus enables the vehicle to load or discharge an arbitrary portion of commodities along the route. This problem concerns the practical situati...