接駁式轉運中心車輛排程之研究

Vehicle Scheduling Problem at a Cross-Docking Terminal

丁慶榮(Ching-Jung Ting) ； 翁偉倫(Wei-Lun Weng)

《工業工程學刊》 20卷6期 (2003/11) Pp. 636-650

摘要

傳統的物流中心在供應鏈中只擔任儲存物品的功能，商品進入物流中心後儲存入庫，等到要出貨前依訂單揀貨；接駁式轉運則是將商品由上游工廠透過物流中心作配送至下游零售點，而不將商品在物流中心儲存入庫的一種方法，經由接駁式轉運可減少商品運送的前置時間並提高顧客服務水準。本研究主要是探討運送貨物進出於接駁式轉運中心的車輛排程模式，討論整合多條配送路線（車隊）的貨車班表（發車間距），使貨物能在最少系統總成本下達到較好的服務水準。本研究所分析的路網主要為單一物流中心的多對多路網，首先藉由各路線獨立的情況下（即未整合策略），建構出路網的數學模式，利用數學解析法，再經由整合的策略，並合併分枝界限法的啓發式解法尋找較佳解，整合的策略分為兩種：共同間距策略以及整數比間距策略。在系統的成本考量上，包含操作成本、庫存成本與轉運成本。由範例分析發現，共同間距策略與整數比間距策略可有效降低系統總成本，但是當路網中有部份供應點與需求點的貨物需求有較大的差異時，整數比間距策略會是較佳的決策。

關鍵字

接駁式轉運 ； 多對多網路 ； 物流系統 ； 整數比間距 ； 分枝界限法

並列摘要

Traditional warehousing had been seen as a ”high-cost function associated with dark and dusty sheds”. But with cross-docking operation, warehousing is now recognized as a vital value-adding link between firms and the supply chain. By arranging for immediate cross docking of incoming product, retailers are able to reduce to a minimum in-transit time for their incoming products. However, cross docking requires close synchronization of all inbound and outbound shipments. In this paper three different control policies at across-docking terminal are compared: uncoordinated, common headway, and integer ratio headways. A heuristic algorithm is developed to optimize both inbound and outbound headways as integer multiples of a base cycle, which is a round fraction of 24 hours, for all coordinated inbound and outbound vehicles. Our results show that integer ratio headways strategy is the best among these three strategies.

並列關鍵字

cross-docking ； many-to-many network ； logistics system ； integer ratio headway ； branch-and-bound

參考文獻

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