Comment on ‘Supply chain model for a deteriorating product with time-varying demand and production rate’ by Giri and Maiti

In a recent article, Giri and Maiti (2012) developed a twoechelon supply chain model with a single buyer and a single vendor, and presented the appropriate theory for the problem. In Case (ii), as the expected number of conforming items produced by the vendor during the time interval [(i 1)Tþ tm, iT ] is less than the buyer’s order quantity, the shortage occurs. For the case considering shortages, the constraint (Equation (18)) on the joint average total cost was given by: