複合運輸貨櫃裝載問題之研究

A STUDY OF THE INTERMODAL CONTAINER LOADING PROBLEM

在大型船舶的時代，貨輪靠港後為使貨櫃能快速由擁擠的碼頭疏散，鐵路為許多港口之重要運輸方式，於國際許多重要港口，此類型海運與軌道複合運輸（intermodal）之裝載貨櫃列車由雙層貨櫃平車（well car）組成，充分利用平車上的空間方能裝載越多貨櫃，成為解決碼頭壅塞問題的關鍵因素，於疫情期間，有效率解決此問題更成為解決塞港問題之重點；此外，為了有效率地利用列車，實務上亦希望能夠用最少的雙層貨櫃平車組成列車達成目標。此問題實務上多依照經驗法則裝載貨櫃、組成列車，為了解決此問題，本研究將此複合運輸貨櫃裝載問題構建為整數規劃問題，期能最大化列車的空間利用率與最小化雙層貨櫃平車的使用數量，並利用商用最佳化軟體求解，實證結果顯示本研究提出之數學模式能於120秒內求解實務規模問題，並針對不同參數進行敏感度分析，進而找出對數學模式求解效率影響較大之參數（例如：目的地數量、平車數目、空櫃造成之載重平衡等），研究成果可供相關單位參考。

In international freight transport, the intermodal transfer of maritime and railway transportation is the primary approach to evacuate the large volume of containers delivered in mega ships in many important ports around the world. In this kind of intermodal transportation, the efficient loading of containers to railway trains becomes a critical and challenge task, especially during pandemic period. In this research, we investigate the container loading problem in such intermodal transport and propose an integer programming formulation to make up the shortfall in conventional manual approach. The proposed formulation is solved by a commercial optimization package. The result of experiments show that the proposed formulation can solve problems of realistic size within reasonable computation time. In addition, the sensitivity analysis identifies the critical parameters that have greater impact on the solution efficiency when solving the proposed formulation. The results can be spread among respective stakeholders to draw their attention to this critical problem and their possible exploitation.