在供應鏈體系下企業營運的各項成本中，運籌配銷系統之區位與途程間所造成的相關成本佔著很大的比例，因而如何降低該項成本是一個重要的研究主題。本研究係針對一般運籌配銷系統中欲決定工廠及物流中心設施區位時，同時加入派車途程的考量，並以考慮工廠及物流中心的位址和各層設施間的派車配送成本為總目標，將工廠、物流中心與零售商三個不同層級所形成之區位途程配送問題嘗試利用一個數學規劃模式予以表示。
由於本研究所探討之問題在解題複雜度上是屬於NP-hard問題，針對一般大型問題無法以正確演算法（Exact Algorithm）求得最佳解。本研究將針對此問題結構提出兩種不同架構的啟發式演算法求解，一為將三層級問題分為兩個兩層級的子問題並以最短距離的幾何概念所發展出之演算法予以求解，另一為以塔布搜尋法為核心同時反覆求解兩層級的啟發式方法，針對小型問題，上述啟發式所得結果將與CPLEX軟體所得結果做比較以驗證上述演算法的求解表現和呈現設施區位與配送途程間的變化。

In a supply chain, the location-routing related cost in a physical distribution system possesses the major working capital. Accordingly, it is an important issue about reducing the location-routing related cost. The purpose of this research is to combine the location-allocation for plants and distribution centers and vehicle routing for facilities and retailers into an integrated mathematical programming model in order to minimize the total setup and operational costs. In many logistic environments, decision markers have to deal with these location selection and vehicle dispatching problems in different levels among plants, distribution centers and retailers.
Since the problem addressed in this research is a NP-Hard problem, it is difficult to solve this problem through the exact algorithm. In this research, we will propose two heuristic solution procedures based on the different approaches in order to solve the related model efficiently. One is based on the shortest distance of geometry while we divide the problem into a two-layer problem. The other is based on tabu search algorithm in order to solve the two-layer problem simultaneously. The performance of the proposed heuristic methods will be compared with the results by using CPLEX package in small size problems and showed the relation between facility location and vehicle routing in order to enhance its visual ability in industry.

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