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POLITECNICO DI MILANO – II Facoltà di Ingegneria LOGISTICS MANAGEMENT (A.Y. 2013/2014) EXAM, 8th 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 MACCHERONI S.p.A. is a pasta manufacturer that wants to build an automated warehouse to store pallet loads (800 x 1200 x h = 1500 mm). The warehouse will be made of single deep selective racks, served by one S/R machine per aisle. In every aisle a pallet location is identified by three values: R/L: right hand side rack/left hand side rack (with respect to the I/O system); PLC: pallet location column (see Figure 1); SL: storage level (see Figure 1). Consider the following design parameters: - storage capacity not lower than 12.000 pallet locations; - throughput capacity not lower than 100 pallet loads/h; - maximum rack length equal to 80 m; - maximum rack height equal to 22,5 m; - dimensions of the bay equal to Length L = 2,8 m; Depth D = 1,3 m; Height H = 1,7 m; - three pallet locations per bay (see Figure 1); - input/output at the 3rd storage level; - horizontal speed (excluding acceleration/deceleration) of the S/R machine equal to 2 m/s; - vertical speed (excluding acceleration/deceleration) of the S/R machine equal to 0,4 m/s; - fixed positioning time equal to 5 s; - fixed time for the fork cycle equal to 10 s; - acceleration + deceleration time equal to 8 s. Assuming furthermore that: - 40 % of the cycles are single command cycles; - F.E.M. 9851 is applicable, 1. (24/30) You are…