由於高度工業化及製造技術的精進，大多數製造商為了兼顧生產量及產品品質紛紛採用大量及自動化生產以因應顧客的需求，即使生產技術日新月異，在生產過程中仍會因機器使用年限增加，零件損耗及毀壞等狀況使生產產品品質不穩定，因此，對製造商而言，在產品出廠前對產品進行檢測是不可或缺的。此外，由於消費者意識抬頭，越來越多消費者對所購買產品品質有更嚴格之要求，因此產品售後保固變得相當重要。對消費者來說，保固是對產品之保障，許多消費者在購買產品時往往將保固列入是否購買因素之ㄧ，也有越來越多製造商希望透過保固增加市場佔有率及顧客滿意度。
不完美生產系統下，適當的產品檢測計劃對製造商而言是相當重要的，一個好的產品檢測計畫可使製造商降低成本，提高品質及增加獲利，因此如何擬定適合檢測政策是廠商最關心的議題，本研究最主要目的在於提供製造商能更有效率的實行產品檢測。因為生產系統不完美，因此假設系統消逝時間服從韋伯分配，而在產品檢測法則上，則是採用負二項分配之特性，只在不可控制狀態系統下進行產品檢測，由生產週期結束後逆向檢測，直到最佳檢測良品數出現為止，此即為本研究之一決策變數，這樣的檢測方法不僅可改善全數檢測過多成本及時間耗費，同時可減少出廠產品之不良品數，而保固方面則是採用免費更換保固政策。此外由於本研究旨在探討不完美生產系統，因此特別將各階段之生產、產品檢測、重製及需求時間皆納入考量，期望使模式更加完備，並探討在不發生延遲交貨下不良品最佳重製時間。而在模式推導完成後，並佐以實例應用及敏感度分析來了解各參數彼此間的關係。本研究希望藉由整合生產系統、產品檢測及保固，對產品進行售前售後之分析，並同時兼顧期望成本最小化及產品品質之原則，以提供製造商進行產品檢測相關決策之依據。

Because of the improvement of technology, mess and automatic production is utilized along with the considerations of lot sizes and product quality to meet the demand of customers. However, since production systems continuously deteriorate due to usage or age such as corrosion, fatigue, and cumulative wear in production processes, the defective rate of products becomes higher, and therefore inspection should be undertaken seriously to ensure the reliability of products in dealing with the upsurge of customer sever quality. Nevertheless, some defective items may still be sold in practice. In such case, warranty policy is essential, because it is an important element in marketing new products as to signify higher product quality and better customers service. Customers may consider the warranty policy as a major factor to decide whether to buy the products, and manufacturers may improve their market share and customer satisfactory by warranty.
In an imperfect production system, a suitable inspection scheme is very important for manufacturers. Since it can reduce total costs, improve product quality and increase sales profit. Therefore how to design a suitable inspection plan for manufacturers is an interested issue for discussion. The purpose of this paper is to provide an inspection scheme for manufacturers to effectively implement the task of quality management. A Weibull power law process is assumed to describe the imperfectness of production systems, and the operating condition of a production system is usually classified into two states：in control and out-of control states. A negative binomial sampling for inspection is adopted. For the out-of control state , the products are inspected inversely in turn in the buffer until the optimal number of conforming products has been collected, and such an optimal number is thus a critical decision to be discussed in this paper. Free replacement warranty policy is assumed, and the considerations of production time, sampling time, rework time, and demand time is integrated into the proposed approach. The optimal rework time of defective items without backordering is also discussed. Finally we evaluate the total cost involving production system, inspection process, and warranty policy to obtain the optimal sampling size and rework time of defective items, in minimizing the expected total cost and improving product quality.

中文部分

楊宗豫，「保證策略之風險分析-不可維修產品的比較研究」，國立台灣工業技術學院管理技術研究所工業管理學程碩士論文，民84。

羅旭君，「不完美生產系統下之最適產品檢測計劃」，國立成功大學工業與資訊管理研究所碩士論文，民94。

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