車輛巡迴路徑問題(vehicle routing problem, VRP)在物流管理中是非常重要的一個問題，其目標函數多為最小化車輛行駛路徑距離與配送車輛數，以減少企業在實體配送方面的運輸成本，隨著現實環境的變遷，越來越多的限制式也增加了車輛巡迴路徑問題的解題複雜度。
距離第一個VRP的提出已經四十多年的時間，許多學者提出不同的求解策略，其中兩階段法(two-phased method)也常用來求解VRP，第一階段以簡單的啟發式解法求得初始解路徑；第二階段再針對初始解予以改良品質。本論文解決多場站、多趟次VRP，利用貪婪法(greedy algorithm)求出初始解，再根據Skitt and Levary 【1985】將多場站、多趟次的車輛巡迴路徑問題，建構成一線性規劃問題，在線性規劃中以行(column)來表示路徑，並且使用行產生法(column generation)，另行建構一整數規劃子問題來產生新的路徑以改善解。
本論文實際求解出不同大小規模的問題，並且與Skitt and Levary實作的結果作比較，進一步分析本論文應用行產生法的解題效率及品質。

Vehicle routing problem plays an important role in logistic management. The objective of a vehicle routing problem is to minimize the fleet traveling distance and the utilization of fleet numbers, so it will decrease the physical distribution cost. With the practical environment changing, more constraints will increase the complexity of vehicle routing problem.
Vehicle routing problem has been studied for more than forty years, and many researchers have used different approaches to solve this problem. Two-phased method is often used to solve a vehicle routing problem. The first phase is to use simple heuristic algorithm to obtain initial routes, and the second phase is to improve the quality of initial solution. We use a greedy algorithm and a column generation method to solve multi-depot and multi-trip vehicle routing problem. According to Skitt and Levary (1985), they constructed a linear problem to model a multi-depot and multi-trip vehicle routing problem. The column represents the route, and they construct another integer programming problem as sub-problem to generate new route.
We calculate different size of problem and compare with the result obtained by Skitt and Levary. Our experimental result shows that using column generation method can get solution efficiently.

Keywords: vehicle routing problem, column generation.

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