Journal of Korea Society of Industrial Information Systems (한국산업정보학회논문지)

Korea Society of Industrial Information Systems (한국산업정보학회)
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Analyzing the Inverted U-shaped Relationship between Inventory Turnover and Energy Efficiency: A study on Korean Steel Companies

재고회전율과 에너지효율성 간의 역-U자형 관계에 대한 분석: 국내 철강기업을 대상으로

  • Received : 2025.03.17
  • Accepted : 2025.04.10
  • Published : 2025.04.30
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Abstract

This study investigates the correlation between inventory management performance and energy efficiency within Korean steel companies. Energy efficiency is conceptualized through the distance function and estimated via Stochastic Frontier Analysis (SFA). Inventory turnover is employed as the metric for assessing inventory management performance among the firms analyzed. A regression analysis was performed to explore the impact of inventory turnover on energy efficiency, with a particular emphasis on identifying an inverted U-shaped relationship between these variables. The principal findings of this study are as follows. Firstly, although a statistically significant inverted U-shaped relationship between inventory turnover and energy efficiency is not observed, the results suggest that improvements in energy efficiency tend to decrease as inventory turnover increases. This finding implies that setting excessively high inventory turnover targets may not necessarily enhance energy efficiency. Furthermore, from the perspective of steel company's operations managers, the result indicates that maintaining an optimal inventory level-one that aligns with each firm's production process characteristics and demand variability-may be more effective in enhancing energy efficiency than pursuing an overly lean inventory strategy. Secondly, the average energy efficiency score among the analyzed steel companies was estimated to be 0.902, indicating that there is potential for improvement in energy efficiency within the Korean steel industry.

본 연구는 국내 철강기업을 대상으로 재고관리성과와 에너지효율성 간의 관계를 검토해 보고자 하였다. 이를 위해 거리함수(Distance Function)에 근거하여 에너지효율성(Energy Efficiency)을 정의한 후 확률변경분석(Stochastic Frontier Analysis)을 통해 에너지효율성을 추정하였다. 그리고 분석 대상 기업의 재고관리성과를 측정하기 위해 재고회전율(Inventory Turnover) 선택하였다. 회귀분석을 통해 에너지효율성에 미치는 재고회전율의 효과를 검토하였으며, 구체적으로 두 변수 간의 역-U자형 관계를 분석하였다. 주요 분석 결과는 다음과 같다. 첫째, 재고회전율과 에너지효율성 간의 완벽한 역-U자형 관계를 확인할 수는 없었으나, 재고회전율이 증가할수록 에너지효율성의 개선 정도가 둔화되고 있다는 점을 확인하였다. 이 결과는 지나치게 높은 재고회전율을 목표로 설정하는 것이 반드시 에너지효율성 개선으로 이어지지 않을 수 있다는 점을 시사한다. 또한 철강기업의 입장에서 재고를 지나치게 축소하는 '과도한 린(Over-lean)' 방식보다는, 기업의 생산 공정 특성과 수요 변동성에 부합하는 최적의 재고 수준을 설정하고 유지하는 것이 에너지효율성 제고에 있어 보다 효과적일 수 있다는 점을 나타낸다고 볼 수 있다. 둘째, 분석 대상 철강기업들의 평균 에너지효율성은 0.902로 측정되었다. 즉, 국내 철강기업의 에너지효율성에 개선의 여지가 있다는 점을 확인하였다.

Keywords

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