Optimal inventory replenishment policy for the EPQ model under trade credit derived without derivatives

The optimal inventory policy for EPQ model under trade credit

“…Under this case, the algebraic method without derivatives may cause some shortcomings such that its validity is questionable. After looking over Huang and Huang (2008), it is found that Huang and Huang (2008) seem to need to explore the functional behaviours of the annual total cost function to justify their solution procedures. So, Huang and Huang's solution procedures are not complete in general.…”

“…Chung and Huang (2003) further generalised Goyal (1985) to the production-inventory system under assumption (A) that the unit selling price and the unit purchasing price are equal. Huang and Huang (2008) modified Chung and Huang (2003) and relaxed assumption (A) to allow that the unit selling price is higher than the unit purchasing price to reflect the reallife situations. Huang and Huang (2008) use an algebraic approach to get the optimal solution for obtaining the pedagogical advantage to promote the EOQ (EPQ) concepts to students who lack knowledge of calculus.…”

“…Huang and Huang (2008) modified Chung and Huang (2003) and relaxed assumption (A) to allow that the unit selling price is higher than the unit purchasing price to reflect the reallife situations. Huang and Huang (2008) use an algebraic approach to get the optimal solution for obtaining the pedagogical advantage to promote the EOQ (EPQ) concepts to students who lack knowledge of calculus. However, the algebraic method has its limit of application when it needs to use the functional behaviours to help to find optimal solutions.…”

“…So, Huang and Huang's solution procedures are not complete in general. The main purpose of this article is to use the analytic approach using calculus to correct and generalise Huang and Huang (2008).…”

“…However, the algebraic method has its limit of application such that validities of proofs of Theorems 1-4 in Huang and Huang (2008) are questionable. The main purpose of this article is not only to indicate shortcomings but also to present the accurate proofs for Huang and Huang (2008). …”