A Cost-Oriented Inspection Decision Tree Model for TFT-LCD Products

• Main Authors: Cheng-Chang Lai, 賴政昌
• Other Authors: Chiuh-Cheng Chyu
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/96861616834699619690

碩士 === 元智大學 === 工業工程與管理學系 === 95 === This thesis proposes a decision tree model to minimize expected total cost for handling the TFT-LCD products after assembly. The factors that influence the total cost include inspection cost, product failure cost, product quality, and lot size. The model consists of a two-stage decision: At stage 1, determining the sample size, and at stage 2, deciding what to do about the remaining products of the lot after observing the sampling outcome. The objective function of the model can be derived according to the decision tree theory. Some properties of this model using Beta priors to represent the product quality are presented, and such findings will help facilitate the computation of the model objective function. A computer program coded in Visual C++ is provided for computing the optimal decisions and the optimal objective value of this model. We studied a real life case in the TFT-LCD industry. A set of data regarding the product quality of a company was collected and used to construct the prior distribution of the product quality. The inspection cost and product failure cost are also estimated using the relevant information from that company. An optimal decision policy on the TFT-LCD products for that company is provided and discussed. Sensitivity analysis as to the model parameters is also performed and the results will provide a good reference for the management to improve their operational procedure. Finally, the research provides several inspection tableaus that can be easily used by the work persons in the assembly line.