隨著高度專業分工的時代來臨，各企業開始僅專注於自身所擅長的核心活動，因此，專業設備租賃漸漸成為主流商業型態，並以合約約束租賃雙方之權利及義務。租賃合約中通常包含由出租者所提供的相關維修保養規定，如出租者必須負擔租期內設備故障的維修責任，且需賠償一金額以補償出租者的停機損失。因此，出租者通常會以預防保養的方式盡可能的減少設備在租期間故障的次數，以減少懲罰成本的支出，進而增加利潤。而實施預防保養的成本與設備故障懲罰成本之間的拉鋸則成為出租者訂定租賃合約與維修策略的重要關鍵。本文以設備出租者的立場，考慮在設備生命週期內，以失效率降低法的保養方式及故障小修的維修方式，以租賃設備為韋伯壽命分配建構數學利潤模式，並推導最佳維修策略與租期數，使出租者之期望總利潤為最大。

Due to professional services come of age, enterprises become only to put the resources into their core activities so that professional equipment leasing turn into a business trend. The rights and obligations are bounded by a lease contract. The rules of corrective and preventive maintenance are usually included in the lease contract and offered by the lesor, such as lessor must be responsible for repair of failure equipment and incurred a penalty cost to compensate for shutdown damage of lessee. Hence, lessor usually implements preventive maintenance actions to reduce the failure times of equipment as less as possible to reduce the penalty cost. Therefore, the choice between implementing preventive maintenance and incurring penalty is a key point of establishing lease contract and maintenance policy. This thesis constructs mathematical profit model for leased equipment with Weibull life-time by using failure rate reduction method and rectifies failures with minimal repairs and derives optimal maintenance policy and number of lease that maximize expected total profit.

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