造船廠船段組合作業排程問題之研究

THE STUDY OF SCHEDULING PROBLEMS FOR BLOCK ASSEMBLY IN SHIPYARD

船段組合（block assembly）作業在一艘船的的建造過程中常扮演重要角色。船段組合作業常受到造船廠的人力、物力及組裝空間等資源調度上的困境，而面臨無法預測工期的情況，甚至因而導致無法準時交船的重大損失。因此，發展出一套具有彈性且符合船廠所需之船段組合排程工具，一直是個重要的課題。基本上，造船廠船段組合作業可視為多重資源限制下的組合最佳化問題（combinatorial optimization problems）。本研究參考以往於造船廠之賞務經驗，延續過去之研究成果，提出一個從多重資源限制下之專案排程問題（resources-constrained project scheduling problem, rcPSP）的角度來面對造船廠之船段組合作業，建立一個在人力、物力、空間等資源受限制以及所屬工種問因資源取用不足而可暫時停工數日後才復工的工作排程模型，同時並發展出一個以禁制搜尋法（Tabu Search, TS）為基礎，用於求解前述多重資源限制下的近似最佳（near optimum）排程方法。經過計算案例測試的結果，證明本文所提出之方法，在效率及效用上均確實可行，且符合造船廠所需，值得造船廠於未來進行相關作業時之參考。 The activities of block assembly often play an important role in the processes of a ship construction. These activities are often deeply affected by resources such as labour, material and working space of a shipyard. Such effects may cause unpredictibility in working schedules and even postponement on the final due date of delivery. Thus, it is important to develop a flexible system which can handle the scheduling problems for block assembly in shipyard. Basically, block assembly in a shipyard can be classified as a combinatorial optimization problem with multiple resources constrained. Base on the past experiences, a new tabu search based algorithm for solving the shipyard scheduling problems with the restrictions of multiple-resources was proposed in this paper. These block assembly processes in a shipyard were treated as a multiple resources-constrained project scheduling problem (rcPSP), and a near optimum mathematical model for the operations can be held and restart while the labour, material and assembly spaces are restricted for using was introduced. The computational results indicate that the methodology proposed isefficiency, effective and meets the needs of shipyard.