Title: An EPQ model for delayed deteriorating items with reliability consideration and quadratic demand
Authors: Sani Dari; Babangida Sani
Addresses: Department of Mathematical Sciences, Kaduna State University, Kaduna, Nigeria ' Department of Mathematics, Ahmadu Bello University, Zaria, Nigeria
Abstract: In this paper, an EPQ model for delayed deteriorating items is developed where the demand before deterioration sets in is assumed to be different from that after deterioration sets in. There are three stages for the inventory system as follows: 1) the production build-up stage (0 ≤ t ≤ L1); 2) stage before deterioration sets in (L1 ≤ t ≤ L2); 3) stage after deterioration sets in (L3 ≤ t ≤ L). It is also assumed that the unit cost of production is directly proportional to the process reliability and inversely proportional to the rate of demand and shortages are not allowed. A numerical example is given to illustrate the developed model and sensitivity analysis carried out on the example to see the effect of parameter changes.
Keywords: economic production quantity; EPQ; quadratic demand; reliability; delayed deterioration.
International Journal of Mathematics in Operational Research, 2020 Vol.17 No.2, pp.233 - 252
Received: 19 Jan 2019
Accepted: 10 Jun 2019
Published online: 21 Sep 2020 *