Study about Joint Online Truck Scheduling and Inventory Management for Multiple Warehouses
Abstract: For a real world problem transporting pallets between warehouses in order to guarantee suffcient supply for known and additional stochastic demand we propose a solution approach via convex relaxation of an integer programming formulation, suitable for online optimization. The essential new element linking routing and inventory management is a convex piecewise linear cost function that is based on minimizing the expected number of pallets that still need transportation. For speed, the convex relaxation is solved approximately by a bundle approach yielding an online schedule in 5 to 12 minutes for up to 3 warehouses and 40000 articles; in contrast, computation times of state of the art LP-solvers are prohibitive for online application.
Introduction: Consider the following real world problem. Given several warehouses connected by a shuttle service of several trucks for shipping pallets of stored articles between them; given also an online stream of orders, that are stochastic in nature and that have to be handled within short time at specific warehouses. Is it possible to provide, online, a schedule of truck routes and truck loads so that all products are available at the right place ahead of processing time even if the realization of the schedule is subject to further uncertainties? We suggest a solution approach based on convex relaxation and demonstrate its practical suitability on real world data of our industrial partner eCom Logistik GmbH & Co. KG. Keep reading…









