近年來，由於民用航空業蓬勃發展，全球主要航空業者紛紛購買更多的客機，以因應越來越多的運輸需求。由於民航機之數量日增，發動機維修需求也快速成長，維修廠也必須擁有合理的零件庫存，以滿足飛機修護需求。雖然有許多學者已經探討過如何將庫存最佳化，但鮮少有學者探討，如何於導入外部資源，打破傳統柏拉圖前緣(Pareto Frontier)之限制，將庫存、利潤以及人力成本推向渴望水準(Aspired Level)。為達此目標，本研究將導入可變空間理論，透過增加預算、改善目標參數與提昇生產效率三種方式，推導渴望水準。本研究以全球主要飛機發動機修護公司之個案為例，實證本分析模式之可行性。分析之結果，除可供該公司將庫存水準最佳化之用。成功驗證的模型，亦可作為其他產業庫存最佳化之用。

During the past years, civic aviation industry grew rapidly. To fulfill the rapid growth of the civic aviation industry, major airlines have purchased more aircraft to fulfill the market needs. Due to the rapid growth of the aircraft numbers, the requirements for engine maintenance increased rapidly. In order to fulfill the needs of engine maintenance, the repair shop must optimize the inventory of parts and materials so as to cope with the engines to be maintained. Although numerous scholars have discussed issues being related to inventory management and optimization, very few scholars have tried to explore how to the inventory can be optimized by introducing external resources, breaking the Pareto Frontier, and reaching the aspired level by optimizing profit and manpower. To fulfill the purpose, the changeable space theory was introduced through increasing budgets, improving objective coefficients; and upgrading production efficiency. An empirical study based on one of the world’s leading engine repair shops was introduced to demonstrate the feasibility of the proposed analytic models. The well-verified analytic models can serve as the basis for the inventory management of the engine repair shop. The changeable space programming based models can also be adopted by inventory management of other industries.

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