城市物流之虛擬越庫選址與路線規劃

Abstract

城市物流是近年來興起之研究議題，城市不斷成長，交通量不斷增加使得許多問題浮現，如交通壅塞、噪音汙染以及廢氣排放等各項對城市的負面影響，致使許多學者投入城市物流相關領域研究。隨著物流業的蓬勃發展，運輸路線規劃問題也逐漸被重視，其可用來評估城市物流，改善城市物流並提高貨運效率。 美國在物流的花費有29%用在存貨(Inventory)方面，8%用在倉儲(Warehousing)方面，4%用在管理(Administration)方面，1%用在雜項開支，和58%消耗在運輸(Transport)方面，由此可知，必須針對運輸路線、存貨等相關物流成本加以管理，以降低物流成本。物流中心選址以及物流中心與顧客之間之運輸路線兩者相互影響，物流中心位址不同將直接影響與顧客之運輸路線。物流中心與顧客之運輸路線不同也直接影響物流中心之選址，兩者須同時考量(Tuzun and Burke, 1999)。而當供應鏈裡存在著越庫，即可透過越庫之特性來加速物流行為，同時也減少存貨。 本研究建置城市物流虛擬越庫選址與路線規劃最佳化模式，最小化物流活動之總成本，相較於過去的區位-途程研究，本研究將城市物流之虛擬越庫選址與路線規劃整合，加入越庫選址之考量，探討越庫之位置與其車隊路網規模之模式，目標為最小化總成本，本研究考慮之城市物流特性，如下所述： (a) 由於市區道路空間之限制，因此將貨車類型分為大貨車及小貨車，大貨車僅能行駛於供應商所在之郊區，小貨車僅能行駛於顧客所在之市區。 (b) 由於城市中之高密集土地利用以及空間限制，故將越庫設定為虛擬越庫。 最後本研究參考國際範例設計一適當規模之情境範例模擬求解，並由範例發展出兩種情境，針對情境一與情境二與範例分析比較。以及對後續研究者提出未來研究方向。

The rise of urban logistics research topic in recent years, increasing traffic volume makes many problems emerge, such as traffic congestion, noise pollution and emissions and other negative impacts on the city. With the rapid development of the logistics, vehicle routing problems which attracts logistics close attention, it can be used to assess city logistics and improve urban freight transport. U.S. logistics spend 29% used in the inventory , the 8% used in the warehousing, the 4% used in the administration, the 1% is used in miscellaneous expenses, and 58% of consumption in the transport, must focus on managing transportation routes, inventory and other related logistics costs in order to reduce logistics costs. Logistics center location and transport routes will influence each other, must be considered together (Tuzun and Burke, 1999). If there is a cross dock in the supply chain , logistics can through the characteristics of the cross docking to accelerate logistics behavior, while also reducing inventory. This study build the virtual cross docking location and routing problem in city logistics model to minimize the total cost of logistics activities, compared to the previous location – routing problem studies, this study adds cross dock and city logistics. This study considered city logistics characteristics, as follows: (A) The urban road space limitations, big trucks can only travel in the outskirts of a city where suppliers are located; small trucks can only travel in the downtown where customers are located. (B) Because of the high density urban land use and space constraints, the cross dock is virtual depot. This study’s sample design from the international question base ,and developed two scenarios for sample analysis and comparison.