可修復航空器材存貨策略之研究

A Study of the Inventory Strategy for Repairable Items of Aircraft Spare Parts

李世淼(Shyh-Miau Lee)

指導教授 ： 林賜德

中原大學/商學院/企業管理研究所/碩士(2006年)

https://doi.org/10.6840/cycu200600240

摘要

摘 要
航材是飛機維護的重心，它不僅直接影響飛機的飛行安全，而且影響飛機的營運成本。昂貴的航材庫存幾乎佔了整個機隊總值的10%，如何既能維持航機的可靠性（Reliability），又能降低航材庫存，一直是每個航空公司所關心的問題。本文將以航空公司可修復航空器材作為研究對象，應用以航材需求為中心的維修理論和成本計算方法等基本理論，以建立可修復航空器材存貨策略的基本模型。
利用維修理論的知識，對可修復航材的週期性需求特點進行初步的了解。並透過對該航材需求特性的分析，以建立符合卜瓦松分配的備料率模型。在此基礎上，根據可修復航材的特點，再建立該航材存貨的基本模型。
另以存貨理論知識為基礎，根據可修復航材庫存期望總成本所需考慮的各項特點，將其區分為購買成本、設置成本、持有成本、缺料成本、修理成本等五項；屏除了傳統可修復航材庫存管理普遍以高度航機支援率為重心，且不重視成本的不科學性、不合理現象，而建立了以存貨成本為核心考量的可修復航空器材存貨模型，以有效地降低庫存期望總成本。
經由本研究所建立的可修復航空器材存貨模型，探討在不同的備料率之下，其相關庫存期望總成本間的變化情形，藉以找出最佳的存貨策略；並透過具體案例來說明本可修復航空器材存貨策略模型在實際情況中的應用，希望能對航空公司的可修復航材存貨管理有所幫助。

關鍵字

可修復件 ； 存貨政策 ； 卜瓦松分配 ； 備料率 ； 存貨成本 ； 航材

並列摘要

Abstract
The core of aircraft maintenance is the spare part, which affects not only flight safety, but also the operation cost of an aircraft. Aircraft spare parts, which amount to nearly 10% of the whole aircraft’s value, are generally considered expensive. So, it has been all airlines’ concern as to how the reliability of an aircraft can be maintained while the inventory cost reduced. This dissertation takes the repairable aircraft spare part as its object of research. With the aircraft spare parts demand-based maintenance and cost calculational methods, an inventory strategy prognosticating model of repairable aircraft spare parts has thus been established.
This research starts with investigating the periodic demands of repairable aircraft spare parts based on the fundamental knowledge of aircraft maintenance. Through the analysis of the regularity of each repairable aircraft spare part, a support rate model which matches the Poisson distribution is established. A basic inventory model for each repairable aircraft spare part is further developed according to the unique feature of each part.
In addition, consolidating the inventory theory and each individual factor that contributes to the expected total cost, leads to five types of cost, which are Purchasing Cost, Setup Cost, Carrying Cost, Stockout Cost and Repairing Cost. It dismisses the traditional non-scientific inventory policy of repairable aircraft spare part that focuses more on the high support rate than the cost. The paper creates an inventory cost driven model for repairable items of aircraft spare parts that can reduce expected total cost effectively.
This inventory strategy prognosticating model explores the optimum inventory for repairable aircraft spare parts by studying changes of the expected total costs among the different support rates. The application of such a model is also presented in this study, which proves to be helpful for airlines in repairable spare parts management.

並列關鍵字

Inventory Policy ； Support rate ； Inventory Cost ； Aircraft spare parts ； Repairable Items ； Poisson distribution

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