"不規則切割問題是許多工業界必然會遇到的問題，如皮革業、成衣業和造船 業等。所謂不規則切割問題是探討在一大片母材上如何盡量切割出許多不規則外 形的型材，而所謂不規則外形是指除了矩形之外的各種形狀，或者是有縷空的型 材。與其他工業所不同的是，造船業的產品非常大，所以它所面對的不規則切割 問題的型材不僅尺寸很大，甚至比母材寬度還長，且外形大凹、多變，使得所面 對的不規則切割問題更複雜，這也是為什麼在造船廠，仍然依靠人力處理不規則 切割問題，以手動方式在母材上安排型材。而在國際期刊中，不規則切割問題相 關論文本就不多，探討造船廠的不規則切割問題的論文更是付之闕如，加上曾嘗 試為造船廠的不規則切割問題實例進行電腦自動排版，結果非常不理想，因此提 出本計畫。本計畫擬收集七個造船廠的不規則切割問題實例進行案例測試，並設 計二階段排版法，從如何將型材分成兩大類個別排版，並且針對船廠的型材特性 設計了六種法則以決定型材之排版順序，然後使用NEST 排版系統來排版，透過 定性方法來了解如何安排船廠型材排版才能獲得比較好的結果。分析的結果將有 助於後續排版最佳化相關研究。" "Irregular stock cutting problem is a common problem encountered in many industries such as leather, clothes and shipbuilding. The problem discusses how to arrange as many irregular shapes to be cut out from a material sheet as possible. A so called irregular shape is the one with irregular contour and/or with inner holes. When compared with the problem in other industries, the problem in shipbuilding is quite different because ships are very large products so as their shapes for the irregular stock cutting problem. That is why, so far, the nesting work is still mainly based on manpower. On the other hand, in many international journals, the papers concerning about irregular stock cutting problem are few and those concerning about the problem in shipbuilding are almost none. In addition, we had ever tried to nest one of practical problems in shipbuilding by computer and its result was terribly bad. Therefore, the project is proposed to understand the irregular stock cutting problem in shipbuilding by qualitative research. In the proposal, total seven practical instances are gathered from shipbuilding companies for case studies. NEST auto-nesting system is used as the tool. A two-stage nesting method is designed especially for the practical instances, where all shapes in every case are going to be divided into two categories by a proposed way and individually nested in different stage. In the first nesting stage, there are six sequencing rules especially designed and based for the first nesting stage. We hope to find out how to nest the shapes in shipbuilding for better results."