隨著經濟的高度成長及電廠興建的日益困難，電力的需求問題是愈來愈嚴重。如何有效率地安排核能機組進行例行性的停機大修及燃料再裝填工作是重要的課題。本論文中考慮核能發電機組五年時程的大修排程問題，我們將這個大修排程問題描繪成一個大型混合型整數線性規劃模型。由於問題的龐大與複雜，此問題的最佳解難以求出。因此，我們發展數個邏輯條件式有效地縮小解集合空間；另外並發展出一個啟發性演算法，採用合併變數法將0/1決策變數合併，使原問題轉成較小的合併模型。先解合併後的合併模型，利用合併模型答案的資訊來固定原始模型的部分變數值之後，再解原始問題。幾個實例計算顯示此演算法的可行性。 / Since the growth of economics and the difficulty to build a new power plant, the supply of electric power has become very tight. It is important to ensure the efficient operation of nuclear power plants, including timely shutdown, refueling and maintenance schedule. In this thesis, we deal with the scheduling shutdown and maintenance of nuclear power plants for a five-year time period. This problem can be formulated as a large-scale mixed integer linear problem. The difficulty of solving this problem is due to the large number of binary variables. We then develop several valid logical constraints to reduce the complexity in processing using the branch and bound technique. Also, a heuristic based on the aggregation and dis-aggregation techniques has been developed to yield a good solution. Several examples are given to show the applicability of the algorithm.