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POLITECNICO DI MILANO – II Facoltà di Ingegneria LOGISTICS MANAGEMENT (A.Y. 2013/2014) EXAM, 22nd JULY 2014 Surname and Name: ___________________________________________ ID number: Please notice: - the overall marks are the simple average of the marks obtained in the single exercises; - for multi-section exercises you find at the beginning of each section the points you get if you answer correctly; - if necessary, introduce the missing data, justifying the choice of the value. Exercise 1 Paper&Co S.p.A., a wholesaler of stationery will replenish almost 250 points of sales in Lombardia and Piemonte from its new distribution centre in Novate Milanese. The picking system for the 2400 medium size items will be a picker to part, low-level, picking system. All the racks will be the same, 1,8 m high and the layout will be as in figure 1. There will be a picking location per each item, and the location will have gross dimensions equal to 0,6 m (depth) x 0,8 m (width) x 0,6 m (height), thus resulting in a system made by 10 couples of aisles. The pickers will use a traversal routing policy and a "batch picking” policy and the sorting will be concurrent with the picking activity. Assuming the following: - (number of orders)/batch: 3; - by using the batch picking policy there is 20% average reduction of the number of order lines compared to the sum of the lines of the orders forming the batch; - average number of orders in a day: 180; - (average number of order lines)/order: 10; - (average number of pieces)/(order line): 3; - set-up time for a picking tour: 40 s; - fixed retrieval time per line: 4 s; - retrieval time per piece (sorting included): 5 s; - average speed of the order picker truck: 1,2 m/s; - utilization factor for the picker: 90%; - one shift per day (duration of the…