本研究介紹了考慮具有時窗及同步服務之情況下一致性車輛途程的問題(Consistent Vehicle Routing Problem with Time Windows and Synchronized Visits；ConVRPTWSyn)，為此問題建立了對應的數學規劃模型，其加入時窗設定來代表顧客可接受的服務時段，另外也加入同步服務的設定來探討最佳化此服務方式的效果。由於現今的服務業興盛，使得行業的競爭策略慢慢地變成顧客至上的商業策略；對此，提升顧客滿意度以及熟悉度成為了策略重點，因此讓同一位司機持續服務同一條路段可以有效地達成此效果，公司方希望能夠藉由同一位司機的服務，來讓司機跟顧客間培養出一個熟悉感，並且有望讓司機能夠更了解其服務的顧客真正需要的服務，同時也盡可能的在每次顧客需要服務的天數，都在大致相同的時間服務，讓顧客培養出一種習慣及方便。在這個問題研究下，本研究提出了一個混合整數線性規劃 (Mixed-Integer Linear Programming；MILP) 模型，並且以大型臨域搜尋法(Large Neighborhood Search；LNS)來求解問題，針對時間一致性以及同步的限制，在其LNS演算法中加入對應的機制，以最佳化此問題的結果。

This research presents a mathematical programming model for the consistent vehicle routing problem with time windows and synchronized visits. The model considers each customer as a different time window associated with the constraints of service requirements represented as a time window and simultaneous visits from different drivers. However, nowadays, habit preference and familiarity are important for most customers. Hence, the same driver and same routine are the new additional requirements considered in the model to give emphasis to customer expectations. Companies want their drivers to develop relationships with customers which can be achieved through the same route and the same drivers visiting the same customers at the same time of the day. A large neighborhood search algorithm was designed to solve the problem. For time consistency and synchronicity, destroy operator was introduced, while greedy heuristic and regret operators deal with inserting and moving the customers to the route. The algorithm is compared to benchmark instances and applied to the entire solution.

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