This paper proposes a tabu search algorithm for the two-echelon vehicle routing problem with time windows and simultaneous pickup delivery (2E-VRPTWSPD), which is new variant of problem. 2E-VRPTWSPD involves three stages routing: (1) first-echelon vehicles start from depot to deliver cargoes satellites; (2) second-echelon satellites serve customers within in simultaneously manner finally return...

STSP seeks a pair of pickup and delivery tours in two distinct networks, where the two tours are related by LIFO contraints. We address here the problem approximability. We notably establish that asymmetric MaxSTSP and MinSTSP12 are APX, and propose a heuristic that yields to a 1/2, 3/4 and 3/2 standard approximation for respectively Max2STSP, Max2STSP12 and Min2STSP12.

Last mile logistics represent one of the most important challenging issues in online grocery shopping. Online customers are expecting high logistical services, demanding convenience, high reliable and on-time delivery services. As such, online retailers have to respond to these expectations by providing convenient logistical services while keeping this process cost efficient as much as possible...