Optimal Lot Sizing, Pricing and Process Reliability Investment Model for an Imperfect Production System with Customer Return

국문 초록 (Abstract)

본 연구는 기업의 불완전한 생산시스템과 판매가격 결정이 기업 내외부에 미치는 영향을 통합적으로 분
석하는 데 그 목적을 두고 있다. 불완전한 생산프로세스에서 산출된 불량품은 고객의 불만족을 일으켜 가
격 결정과 더불어 고객의 수요에 영향을 미치게 된다. 또한 불량품은 교환 및 환불의 형태로 반품되고, 재
작업, 이차 시장으로의 판매 및 폐기 등의 형태로 재처리되면서 추가적인 비용을 일으켜 기업의 이익에 음
의 영향을 미치게 된다. 따라서 본 연구는 기존의 연구가 다루지 않은 기업의 현실적인 상황을 고려하여
이익을 최대화하는 생산로트 크기, 판매가격, 허용불량률 및 재작업 횟수를 통합적으로 결정하는 모형을
제시하고 있다. 해법에 있어서 모형의 수학적 복잡성으로 인해 폐쇄형 최적해를 구할 수 없으므로 먼저 미
분을 통해 목적식을 간소화한 후 비선형 모형을 개발하여 이에 대한 최적해를 도출하고 이를 수리적으로
예시하고 있다. 또한 민감도 분석을 통해 모형 변수들의 행태를 분석하고, 이를 통해 기업 실무에서 마케
팅 및 생산 각 부문의 통합적 의사결정에 필요한 주요 변수들에 대한 실무적 시사점을 제시하고 있다.

다국어 초록 (Multilingual Abstract)

This study aims at examining both internal and external effects of an imperfect-quality production system
along with a pricing decision in practice. The problem investigated involves a production system that
follows a non-deteriorating stable process, generating binomial yields, thereby passing defective items to
customers and negatively affecting demand along with a firm’s pricing decision. Then customers return
those defectives for exchange or refund, and the firm disposes them through rework, salvage, or scrap.
For this previously unexplored problem of practical significance, we develop a nonlinear profit-maximization
model of jointly determining production lot size, rework frequency, defective proportion and selling price.
In solution, due to the mathematical complexity of the model in finding optimal closed-form solutions, we
first reduce the objective function using differential calculus and then develop a nonlinear programming
model to obtain global optimal solutions. We present a numerical example and conduct extensive sensitivity
analyses to illustrate critical behaviors of model variables, in order to provide important managerial
insights into practice in making comprehensive marketing and production decisions.

목차 (Table of Contents)

• Abstract
• Ⅰ. Introduction
• Ⅱ. Literature Review
• Ⅲ. Integrated inventory model and optimal solution
• Ⅳ. Sensitivity Analyses and Managerial Implications
• Ⅴ. Concluding Remarks
• References
• 요 약

참고문헌 (Reference)

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