(Continue with 6.11) The decision maker also wants to comsider another objective: minimizing lead time; however he or she believes minimizing cost is more important than minimizing lead time: Formulate this multi-objective problem as preemptive GP model. Let A and B be the target value for cost and lead time, respectively. The expected lead times of the product from Supplier 1, Supplier 2, and Supplier 3 are 5, 6 and 7 days, respectively

6.11 Consider an order allocation problem under multiple sourcing, where it is required to buy 2000 units of a certain product from three different suppliers. The fixed set-up cost (independent of the order quantity), variable cost (unit price), and the maximum capacity of each supplier are given in the following (two suppliers offer quan- tity discounts): Supplier Fixed Cost $100 1 23 $500 $300 Capacity 600 units 800 units 1200 units Unit Price $10/unit for the first 300 units $7/unit for the remaining 300 units $2/unit for all 800 units $6/unit for the first 500 units $4/unit for the remaining 700 units