The Journal of the Convergence on Culture Technology (문화기술의 융합)

The International Promotion Agency of Culture Technology (국제문화기술진흥원)
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An Inventory Model for Deteriorating Products with Ordering Cost inclusive of a Freight Cost under Trade Credit

신용거래 하에 운송비용이 포함된 주문 비용을 고려한 퇴화성 제품의 재고 모형

  • 신성환 (한라대학교 신소재화학공학과)
  • Received : 2018.09.28
  • Accepted : 2018.12.09
  • Published : 2019.02.28
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Abstract

Trade credit is being used as a price discrimination strategy by the suppliers in order to increase the customer's demand. From the viewpoint of the customer, if delayed payment is allowed for a certain period of time from the supplier, the effect of reducing the inventory carrying cost will positively affect the customer's order quantity. Also, in deriving the economic order quantity(EOQ) formula, it is tacitly assumed that the customer's ordering cost is a fixed cost. However in many business transactions, the customer pays the freight cost for the transportation of his order and so, the customer's ordering cost contains not only a fixed cost but also a freight cost which is a function of the order size. Therefore, in this study, we analyzed the inventory model which considers that the customer's ordering cost contains not only a fixed cost but also a freight cost which is a function of the customer's order size when the supplier permits a delay in payments. For the analysis, it is also assumed that inventory is exhausted not only by customer's demand but also by deterioration. Investigation of the properties of an optimal solution allows us to develop an algorithm whose validity is illustrated using an example problem.

신용거래는 공급자가 고객의 수요를 증대 시킬 목적으로 경쟁 업체와의 가격 차별화 전략의 하나로 활용되어진다. 고객 입장에서 보면 공급자로부터 제품 대금에 대하여 일정 기간 동안 지불 유예가 허용되면, 재고 투자 비용이 절감되는 효과가 발생하고 결국 고객의 재고 정책에 긍정적인 영향을 미치게 된다. 전통적인 재고 모형의 경우 고객의 주문 비용은 주로 고정 비용으로 가정하였다. 그러나 많은 실제 문제의 경우, 고객은 고정 주문 비용과 함께 제품 운송을 위한 운송비용을 부담하고 있으며, 대부분의 운송비용은 구입량(주문량)에 따라 종속적으로 발생하게 된다. 본 연구에서는 공급자가 고객에게 제품 대금에 대하여 일정 기간 동안 신용거래를 허용하는 상황 하에서 고객의 주문 비용이 고정 주문 비용과 함께 주문량에 따라 종속적으로 발생하는 운송 비용을 포함한 재고 모형을 분석하였다. 문제 분석을 위하여 재고는 시간이 경과함에 따라 일정률로 퇴화한다는 가정 하에 고객의 연간 총 재고 비용에 대한 모형을 수립하였고, 총비용을 최소화하는 경제적 주문량 결정을 위한 해법을 개발하였다.

Keywords

GJMGCK_2019_v5n1_353_f0001.png 이미지

그림 1. 재고수준(q(t)) vs. 시간(t) Figure 1. Inventory level (q(t)) vs. Time (t).

GJMGCK_2019_v5n1_353_f0002.png 이미지

그림 2. 신용기간(tc) vs. 주기시간(T), tc ≤ T Figure 2. Credit Period (tc) vs. Cycle Time (T).

GJMGCK_2019_v5n1_353_f0003.png 이미지

그림 3. 신용기간(tc) vs. 주기시간(T), tc > T Figure 3. Credit Period (tc) vs. Cycle Time (T).

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