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POLITECNICO DI MILANO LOGISTICS MANAGEMENT (A.Y. 2019/2020) EXAM SIMULATION, May 2020 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 Exercise 1 “Smell&Clean”, a producer of health&care products needs to build a new storage system, made by single deep selective racks, served by counterbalanced forklift trucks. Assuming the following: - required storage capacity: 4,000 pallet locations; - maximum pallet load dimensions: 800 x 1200 mm x h=1500 mm; - pallet locations per bay: 2; - building available height: 8.5 m; - input/output point in the corner; - fixed length of the working aisle: 50 m; - width of the working aisle: 2.8 m; - width of the across aisle: 3 m; - upright width and beam height: both 100 mm; - distance between upright and pallet load, between two pallet loads in the bay: 100 mm; - clearance between the top of the pallet and the above beam: 150 mm; - distance between two opposite pallet loads in the facing racks: 200 mm - horizontal speed of the truck: 2 m/s; - vertical speed of the forks (up and down): 0.4 m/s; - maximum height reachable by the forks: 7.5 m; - fixed time for a single command cycle (fork cycle, positioning…): 50 s, you are requested to: (24/30) design the storage system and determine the minimum number of trucks to provide a throughput capacity of 160 single command cycles/h, assuming the same probability to access each pallet location; (6/30) determine the minimum number of trucks to provide a throughput capacity of 160 single command cycles/h, assuming to divide the storage system in two areas as reported in table 1. %…