排程問題是一重要且廣受學者與業界討論之議題。排程問題有許多種類型，針對不同型態的排程問題，其問題模式也不盡相同。在生產系統中，各製程大都由一台以上同種類型的機器設備所組成，如何安排製程中各機台加工工作的排程，以提昇產出速率與機器的使用率，即為排程理論中的平行機台排程問題。過去的許多文獻大都使用啟發式演算法或各種數學規劃求解。由於現實環境的排程問題是經常變動的且具有許多製程特性上的限制，使用啟發式演算法能迅速有效地求解。而實際的生產過程中也存在許多不確定的因素，若將模糊理論應用於排程問題，可使求解結果更具有彈性且更能符合真實情況。
許多產業的生產作業環境屬於等效平行機台，包括薄膜液晶顯示器（TFT-LCD）產業。TFT-LCD製程依序為陣列、組立及模組三部分，其中，組立段製程為良率最低且機台特性最複雜的階段，使得排程具有一定的困難度。本研究針對TFT-LCD面板組立段製程，在機台總閒置時間最小化的排程目標下，分別使用兩數學規劃模式及啟發式演算法求解，並比較求解方式的異同及績效。

Scheduling is an important issue that has been discussed widely in the business and academic literature. It includes many types of problems, and many types of models have been developed to solve these. Most production processes are composed of one or more homogeneous machines. The scheduling problem with parallel machines aims to improve the production speed and utilization of machines by better arrangement of manufacturing work done by each machine. Most previous research uses heuristic and mathematical programming methods to solve such problems. Because scheduling problems often change frequently and there are many limits to production characteristics, heuristic methods can solve the problems effectively and rapidly. In addition, there are many uncertain factors in the production environment, and if we apply fuzzy theory to scheduling, it may produce more flexible solutions that better suit real world applications.
Numerous production environments utilize the uniform parallel machines, including the Thin Film Transistor-Liquid Crystal Displayer (TFT-LCD) industry. The manufacturing of TFT-LCD includes array, cell, and module assembly processes. The cell assembly process has the lowest yield rate and most complexity, meanings that the scheduling has a high degree of difficulty. This study builds two mathematical programming models and a heuristic algorithm to minimize machine idle time to solve the scheduling problem. This study also evaluates models with different parameters and compares their performances.

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