An Inventory Model for Tri-Stage Supply Chain with a Warehouse, Stochastic Demand and Multi Retailers and Vendors

This research considers a tri-stage supply chain with three vendors, four retailers and a warehouse entitled by vendor management inventory (VMI) to support the vendors. In the proposed model, the annual order and warehouse capacity is limited. Also demand is probabilistic and follows from Normal density function. The main goal is minimization of the total cost of supply chain such as holding and ordering cost for retailers, vendors and warehouse. An integer non-linear programming (INLP) with stochastic demand is designed, then is solved and analyzed by CPLEX software and Taguchi method.