Khalil, Moayad2013-12-122013-12-122013-12-12http://hdl.handle.net/10222/42643Order picking is considered one of the most time-consuming operations in picker-to-parts warehouses. Accordingly, more emphasis has been given to the task of improving the efficiency of order picking systems in general, and the required traveled distance during the order picking operation, specifically. In this thesis, we focus on two main factors that significantly affect the efficiency of order picking systems: the assignment storage policies, including the full-turnover, nearest-location and random storage policies; and the warehouse layout structure, in terms of the depth and the number of storage aisles. We investigate the combined effects of these two factors on the order picking travel distance. While previous research compares the full-turnover to the random storage policy, we compare the performance of the full-turnover policy to the nearest-location and random storage policies over various warehouse layout alternatives. For this purpose, we present a methodology for estimating order picking travel distance in a single-block, open-ended warehouse, under the assumptions of S-shape routing and discrete order policies.enWarehousesOrder PickingFacilities DesignTravel Distance