配送與運輸策劃【外文翻譯】

1、<p><b>　　外文翻譯</b></p><p><b>　　原文</b></p><p>　　Distribution and Transport Planning</p><p>　　Material Source:</p><p>　　Bernhard Fleischmann&l

2、t;/p><p>　　University of Augsburg, Department of Production and Logistics,</p><p>　　Universitatsstrabe 16, 86135 Augsburg, Germany</p><p>　　Planning Situations</p><p>　　Tr

3、ansport Systems</p><p>　　Transport processes are essential parts of the supply chain. They perform the flow of materials that connects an enterprise with its suppliers and with its customers. The integrated

4、view of transport, production and inventory holding processes is characteristic of the modern SCM concept.</p><p>　　The appropriate structure of a transport system mainly depends on the size of the single sh

5、ipments: Large shipments can go directly from the source to the destination in full transport units, e. g. trucks or containers. Small shipments have to be consolidated in a transport network, where a single shipment is

6、transshipped once or several times and the transport is broken at transshipment points (TPs). A particularly effective consolidation of small shipments is achieved by a logistics service pr</p><p>　　The cons

7、olidation of transport flows decreases the transport cost. As the cost of a single trip of a certain vehicle on a certain route is nearly independent of the load, a high utilization of the loading capacity is advantageou

8、s. Moreover, the relative cost per loading capacity decreases with increasing size of the vehicles. But even with a strong consolidation of shipments to full loads, e. g. by an LSP, the smaller shipments cause relatively

9、 higher cost, because the consolidation requires det</p><p>　　The following transport processes occur in a supply chain:</p><p>　　? The supply of materials from external suppliers or from an own

10、 remote factory to a production site. Both cases are identical from the viewpoint of logistics.</p><p>　　? The distribution of products from a factory to the customers. The distribution system depends on the

11、 type of products:</p><p>　　– Investment goods, e. g. machines or equipment for industrial customers, are shipped only once or seldom on a certain transport link.</p><p>　　– Materials for produc

12、tion are also shipped to industrial customers, but regularly and frequently on the same path.</p><p>　　– Consumer goods are shipped to wholesalers or retailers, often in very small order sizes (with an avera

13、ge below 100 kg in some businesses),</p><p>　　requiring a consolidation of the transports.</p><p>　　Note that the transport of materials from factory to factory is part of the distribution funct

14、ion of the supplier as well as part of the procurement function of the receiver. Transport planning is usually the responsibility of the supplier. But there are important exceptions, e. g. in the automotive industry, whe

15、re the manufacturer controls the transports from his suppliers. In this case, transport planning occurs on the procurement side as well.</p><p>　　An LSP may consolidate the transport flows of several ”shippe

16、rs”, operating in separate supply chains, in his own network. Then he is responsible for planning how the transports are executed, i. e. by which vehicles along which routes. However, the decisions on the transport order

17、s, i. e. the quantity, source and destination of every shipment, remain a task of the APS of the shipper. Usually, it is not practicable to include the flows of all other shippers of an LSP into the APS. However, the ad&

18、lt;/p><p>　　Distribution Systems</p><p>　　A typical distribution system of a consumer goods manufacturer comprises the flow of many products from several factories to a large number of customers. P

19、roducts made to stock are often shipped first to central DCs on forecast. The deliveries of the customer orders may then use the following distribution paths:</p><p>　　Shipments may go directly from the fact

20、ory or from a DC to the customer, with a single order. This simplest form of distribution is only efficient for large orders using up the vehicle. Smaller orders can be shipped jointly in tours starting from the factory

21、or DC and calling at several customers. A stronger bundling of small shipments is achieved by a joint transport from the DC to a TP and delivery in short distance tours from there. Figure 12.1 illustrates the different d

22、istribution paths.</p><p>　　The transport of materials for production, as far as controlled by the supplier, is mostly done in direct shipments. A recent concept for the supply of standard materials is the v

23、endor managed inventory (VMI), where the supplier decides on time and quantity of the shipments to the customer but has to keep the stock in the customer’s warehouse between agreed minimum and maximum levels. In this cas

24、e, the customer’s warehouse has the same function as a DC, so that the planning of VMI supply is simi</p><p>　　Procurement Logistics Systems</p><p>　　If a manufacturer controls the transports of

25、 materials from his suppliers, he can use various logistics concepts, which differ in the structure of the transportation network and in the frequency of the shipments. They may occur in parallel for different classes of

26、 materials for the same receiving factory.</p><p>　　Cyclical procurement in intervals of a few days up to weeks permits to bundle the transport flow into larger shipments, but generates cycle stock at the re

27、ceiving factory. JIT procurement with at least daily shipments avoids the inbound material passing through the warehouse. Instead, it can be put on a buffer area for a short time. If the arrivals are even synchronized wi

28、th the production sequence, the material can be put immediately to the production line where it is consumed. The latter case </p><p>　　The following transport concepts exist for procurement:</p><p

29、>　　? Direct transports from the supplier are suitable for cyclical supply and, if the demand is sufficiently large, also for daily supply. Only if the distance is very short, direct transports may be used for synchron

30、ized procurement.</p><p>　　? A regional LSP collects the materials in tours from all suppliers in his defined area, consolidates them at a TP and ships them in full trucks to the receiving factory. This conc

31、ept permits frequent supply, up to daily, even from remote suppliers with low volume. The trunk haulage can also be carried out by rail, if there are suitable connections.</p><p>　　? An LSP warehouse close t

32、o the receiving factory suits for synchronized procurement: The LSP is responsible for satisfying the short-term calls from the receiver by synchronized shipments. The suppliers have to keep the stock in the warehouse be

33、tween agreed minimum and maximum levels by appropriate shipments, like in the VMI concept.</p><p><b>　　Models</b></p><p>　　Transport and Inventory</p><p>　　Transport pla

34、nning has a strong impact on the inventory in the supply chain. It directly creates transport lot-sizing stock and transit stock (see Sect. 2.4) and influences the necessary safety stock. The lot-sizing stock results fro

35、m the decision on the transport frequencies. Unfortunately, the present APS do not (yet) support the optimization of mid-term transport planning with regard to inventory. Nevertheless, this section presents some generic

36、planning models, since the resulting frequencie</p><p>　　Transportation and Safety Stocks</p><p>　　In a distribution system for products made to stock, the safety stocks that are necessary for g

37、uaranteeing a certain service level, depend on the strategy of the transports between the factory and the DCs (see Silver et al. (1998, Chap. 12.4)): In a strong push system any production lot is distributed immediately

38、to the DCs. A modification consists in retaining some central safety stock at the factory warehouse which is distributed in case of imminent stock-out at some DC. In a pull system, tran</p><p>　　The push sys

39、tem corresponds to the case of synchronized production and distribution and thus requires less cycle stock, but in general higher total safety stock or more cross-shipments between the DCs. The local safety stock at a DC

40、 has to cover the local demand uncertainty during the transport leadtime, the total system safety stock has to cover the total demand uncertainty during the production lead-time and cycle time. In a consumer goods distri

41、bution system, the transport cycle time is usual</p><p>　　Deployment</p><p>　　The general task of deployment is to match the short-term demand with the available and expected stock for the next

42、day or few days. As the source locations (factories, suppliers), where stock is available, are in general different from the demand locations (DCs, customers), it has to be decided how much to ship from which source loca

43、tion to which demand location.</p><p>　　Delivering Known Customer Orders</p><p>　　In a make-to-order situation, the completion of the orders in due time is the responsibility of production plann

44、ing and scheduling. Deployment can only deal with completed orders ready for delivery, and the shipment size is fixed by the customer order.</p><p>　　In a make-to-stock situation, many customer orders may co

45、mpete for the same stock. If the stock at every source is sufficient for the normal allocation of orders, again, all order quantities can be released for delivery. </p><p>　　Otherwise, ATP decisions about me

46、asures against shortage have to be taken as explained in Sect. 12.1.3. If there are several sources with sufficient stock in total, reallocations can be made, either by transshipments from source to source or by directly

47、 reallocating certain customer orders from their normal source to an exceptional one. The latter measure is both faster and cheaper, in particular if customers are selected near the border between the delivery areas of t

48、he concerned sources. While</p><p>　　The optimal combination of the measures against shortage for all customers competing for the stock of a certain product can be determined with the above network flow mode

49、l, with the following interpretation:</p><p>　　? Every customer j is modeled as a demand location.</p><p>　　? Besides real locations with available stock, the source “l(fā)ocations” i include other

50、potential measures, in particular a “source” with unlimited availability that stands for reducing or canceling orders.</p><p>　　? The cost cij includes penalties for delaying, reducing or canceling a custome

51、r order, depending on the priority of the customer.</p><p>　　Replenishment of DCs and Procurement</p><p>　　Shipment quantities for replenishment and procurement are not determined by customer or

52、ders but have to be derived from Demand Planning. Moreover, the calculation requires the prior specification of a certain transport cycle time (or of the transport frequency) for every relation, as explained in Sect. 12.

53、2.1.</p><p>　　The net demand for a shipment is then</p><p>　　dN = demand forecast at the destination</p><p>　　during the following transport cycle and the transport lead-time</p&

54、gt;<p>　　+ safety stock for the destination</p><p>　　./. available stock at the destination.</p><p>　　In a pull system the shipment quantity is set equal to dN, if there is sufficient sto

55、ck at the source for all destinations. The quantities may be modified by a vehicle loading procedure, as explained below. If the stock at the source is not sufficient, it is allocated to the destinations using a “Fair Sh

56、ares” rule which takes into account the demand and stock situation of every destination and therefore requires global information and central control (see Silver et al. (1998, Chap. 12.4.3)). The</p><p>　　Di

57、stribution Requirements Planning (DRP) (see Silver et al. (1998, Chapter 15.6)) can be used to propagate the net demand upstream in a network, if 12 Distribution and Transport Planning 241 every node is supplied by a fix

58、ed single source. It is an extension of the MRP demand calculation to the distribution network and permits, like MRP, to consider time-phased dynamic demands and lead times from node to node.</p><p>　　In a p

59、ush distribution, every supply arriving in the source is immediately distributed to the destinations according to fair shares. In case of short transport lead-times and long supply cycles for the source, it is advantageo

60、us to retain some central safety stock at the source which is distributed later according to updated fair shares.</p><p>　　In the case of shortage, the determination of the DC replenishment quantities can al

61、so be integrated in the network flow model, together with the deliveries of customer orders, where a DC appears as demand location with the above net demand.</p><p>　　Vehicle Loading</p><p>　　Th

62、e previous calculations of shipment quantities are carried out separately for every product. They do not consider joint shipments of many products in appropriate transport units (e. g. whole pallets). This is the task of

63、 vehicle loading which starts from those shipment quantities and fits them to the vehicle capacity. As far as the quantities represent net demand, they can only be increased, but in general, the demand calculation can sp

64、ecify minimum quantities below the proposed quantities. An</p><p>　　? round up or down the shipment quantity of every product to whole transport units (e. g. pallets),</p><p>　　? adjust the size

65、 of the joint shipment, i. e. the sum of the single product quantities, to a full vehicle capacity, where the vehicle is eventually selected from a given fleet.</p><p>　　Both steps have to consider the minim

66、um quantities and the available stock, the second step should try, within these bounds, to balance the percentages of increase (or decrease) over the products.</p><p>　　Vehicle Scheduling</p><p>

67、;　　As explained in the previous section, vehicle scheduling has only a limited importance for advanced planning. Therefore, and in view of the huge body of literature, models and algorithms for vehicle scheduling, this s

68、ubject is not dealt with here. Instead, the reader is referred to the following review articles. Most literature concerns scheduling round trips of vehicles starting and ending at a single depot. This case is relevant fo

69、r delivering small orders to customers from a TP and for collec</p><p>　　Vehicle scheduling for trunk haulage, as it occurs on the relations factory– DC, DC – TP, for direct deliveries to customers and in pr

70、ocurement transports, has been investigated only recently (see Stumpf (1998)).</p><p><b>　　譯文</b></p><p><b>　　配送與運輸策劃</b></p><p>　　材料來源：奧格斯堡大學，生產(chǎn)和物流部，大學</

71、p><p>　　路16號，86135，奧格斯堡，德國 作者：伯恩哈德·弗萊舍曼</p><p><b>　　運輸系統(tǒng)</b></p><p>　　運輸環(huán)節(jié)是供給鏈上的重要組成部分，它主導了物資的流動，幫助企業(yè)在供貨商與顧客群間搭橋牽線。而由運輸、生產(chǎn)和庫存構(gòu)成的過程整合，觀念上，恰恰表現(xiàn)出了現(xiàn)代供應鏈關(guān)系管理概念的特征。<

72、/p><p>　　一個結(jié)構(gòu)合理的運輸系統(tǒng)應該建立在單程裝運的規(guī)模之上：大批量貨物可以通過各種貨運單位（如，卡車或集裝箱）由起運地直接運往目的地；小批量貨物則須在運輸過程中進行重組，并將在運輸網(wǎng)絡的轉(zhuǎn)運點(TPs)，經(jīng)歷一次甚至多次的轉(zhuǎn)運。其中，物流服務供應商(LSP)作為一個聯(lián)結(jié)了諸多發(fā)送者的匯集點，為小批量貨物的運送模式提供了尤其有力的保證。</p><p>　　運輸流動的整合化能達到降低成

73、本的目的。對于一次單程運輸，假定它的運輸路線與交通工具都是特定的，若它能夠無需考慮載運量的限制，也就是說它最大程度地利用了載貨空間，那這次運輸?shù)某杀緹o疑將被大大降低。此外，每單位載貨量相對成本的減少往往伴隨著運輸工具的型號增大，但即使能達到高效率運輸與滿載這兩個條件，舉例說來，通過物流服務供應商，一次規(guī)模相對較小的貨運還是會產(chǎn)生一筆較高的費用，因為它參與了集中托運便意味著將會被迫繞行到另外的運點，負擔了額外的停靠及轉(zhuǎn)運所產(chǎn)生的費用（參見

74、，弗萊舍曼（1998年，第65頁）） 。</p><p>　　以下為供應鏈中的運輸流程：</p><p>　　以物流的角度看來，物資供應是來自外部供應商還是本部偏遠廠家，這點并無差別。</p><p>　　產(chǎn)品分配指的是產(chǎn)品由工廠流向顧客的過程。此分配制度的內(nèi)容具體依產(chǎn)品類型而定：</p><p>　　— 投資品，如機械品或工業(yè)客戶所需設備，

75、一般只參與運輸一次，或者很少處在某個固定的運輸線上。</p><p>　　— 產(chǎn)品的原材料也是運往工業(yè)客戶，但相比設備，它的運輸路線則是固定的，且周期規(guī)律，頻率高。</p><p>　　— 消費品則是運往批發(fā)商或零售商處，他們的需求量往往很?。承┵Q(mào)易中，每次運輸平均在100公斤以下），這時便需進行集中托運。</p><p>　　需要注意的一點是，工廠間的材料運輸，

76、既屬于供貨方的分發(fā)職能，同時也是收貨方采購職能的一部分。一般情況下，運輸策劃的制定是屬于供貨方的職責，但也有例外，而且這個例外還相當重要，例如汽車工業(yè)便是由制造商代替供貨商，掌握著運輸?shù)目刂茩?quán)，這種情況下，運輸策劃權(quán)在采購方。</p><p>　　一個物流服務供應商能夠集結(jié)幾個承運商的運輸流線，并通過一定的操作，將多個相對獨立的供應鏈融合到自己的運輸網(wǎng)絡里來。然后他將負責策劃出有效的運輸流程，也就是說，由他決定哪

77、條路線派哪輛車。而運輸單的確定，即數(shù)量、起運點和目的地的確定，仍然是屬于承運商個體的高級計劃系統(tǒng)內(nèi)的任務。因為通常情況下，將物流服務供應商下其他承運人的運輸流線歸并到一個高級計劃系統(tǒng)里來，是不具備可行性的。不過額外的運輸流線還是會對運輸成本產(chǎn)生影響，而且這點應被毫無疑問地考慮到相應的運輸成本函數(shù)中去。</p><p><b>　　配送系統(tǒng)</b></p><p>　　

78、一個典型的配送系統(tǒng)，假定那是服務于一個消費品制造商的，它的流線將擔負起把大量的制成品由多個工廠輸送到眾多客戶的手中這個任務。貨物一般會預先被集中運往主要配送中心存儲起來，之后再根據(jù)不同的客戶需求選擇相應的配送路線：</p><p>　　物流公司也許會按照運單直接將貨品由工廠或是配送中心發(fā)到顧客手中。這也是配送方式中最簡單的一種，但只適合于那些需要派出所有車輛才能完成的大訂單。而較小的訂單則會在運輸途中被物流公司分

79、揀合并，而后進行統(tǒng)一配送。小批量貨物的有效捆綁的實現(xiàn)是借助了從配送中心到轉(zhuǎn)運點途中的聯(lián)運，以及由轉(zhuǎn)運點開始的短距離配送。圖12.1展示了不同的配送路線。</p><p>　　至于那些由供應商控制著的原材料的運輸大多數(shù)還是直接出貨的。當下對標準材料供應的最新定義便是供應商管理庫存（VMI），它指由供應商決定運貨的時間和數(shù)量，但貨物需按協(xié)議的數(shù)量儲存在客戶的倉庫中。這種情況下，客戶的倉庫便在功能上等同了一個配送中心，

80、也就是說，供應商管理庫存的供應計劃實際上就類似于配送中心的庫存計劃。</p><p><b>　　采購物流系統(tǒng)</b></p><p>　　如果一個制造商代替他的供應商控制了原材料的運輸，他的物流選擇便多了起來，不用再受既定的運輸網(wǎng)絡和貨運頻率所限制。這對不同種類的材料一樣適用，但前提是接收工廠應是同一個。</p><p>　　幾天到數(shù)周的間隔

81、時間內(nèi)，周期性采購是允許將運輸流線捆綁到更大的貨運批次中去的，但如此一來也會相應產(chǎn)生接受工廠存貨周期化的問題。所以貨物批次至少是每日一次的及時制采購應該避免回流材料經(jīng)過倉庫，而是尋一處緩沖地帶將貨品暫放上一段時間。若是已到材料與制作工序達到了同步，這些材料就應立即投入生產(chǎn)線參與生產(chǎn)。</p><p>　　以下是采購環(huán)節(jié)中的運輸概念：</p><p>　　服務于供應商的直運對于周期性供貨也是

82、適合的，同時，若是貨物需求量足夠大的話，每日供應也不是不可以。但只有在運輸距離非常短的前提下，直運才有可能與采購做到同步。</p><p>　　區(qū)域性物流服務供應商先將來自所有供應商的原材料納入自己的運輸系統(tǒng)，在轉(zhuǎn)運點做好集中工作，再將它們以一定的次序裝上貨車，達到高效利用載貨空間的目的，最后運往各自的接受工廠。</p><p>　　物流服務供應商的倉庫應該選在接受工廠的附近，以便到貨能與

83、采購達到同步。物流服務供應商應負責滿足收貨人對于同步到貨的短期需求，相應地，供應商也應依照協(xié)定的數(shù)目負責看管倉庫中的存貨，這點類似于供應商管理庫存的相關(guān)內(nèi)容。</p><p><b>　　運輸和安全庫存</b></p><p>　　在服務于用作存儲的貨品的配送系統(tǒng)中，為了保證某個特定的服務水平，安全庫存是非常有必要被考慮進工廠與配送中心間的運送策略的。（參見《銀證》（

84、12.4章，1998））。緩沖包括保證工廠倉庫中的分配到的安全庫存以應對配送中心里的即將發(fā)生的庫存不足。在拉式系統(tǒng)中，運輸行為是由各個配送中心所在地的庫存狀況達到了一定的再訂購點而引發(fā)的，而各個配送中心所收集的需求和存貨狀況方面的全球信息也會集中反饋到中心部門……</p><p>　　拉式系統(tǒng)有些類似于生產(chǎn)配送同步化的案例，對于周期性的庫存也應按需減少。地方性的安全庫存在訂貨至交貨時間及周期性時間內(nèi)，必須覆蓋到所

85、有不確定需求因素。在一個消費品配送系統(tǒng)內(nèi)，周期運輸時間通常情況下是很短的，因為配送中心每天都在接受著貨源補充，但要是遇上生產(chǎn)線緊張的情況，貨品運送周期時間也許會持續(xù)上數(shù)周甚至數(shù)月。因此，系統(tǒng)內(nèi)安全存貨的計算應該建立在相當于生產(chǎn)周期的定期回顧性自查的基礎上。</p><p><b>　　配送中心補貨與采購</b></p><p>　　裝船補貨和采購并不取決于客戶的訂單，

86、但也必須要按照需求計劃來操作。此外，補貨和采購的計算需要在每次聯(lián)系時優(yōu)先說明運輸周期時間（或運輸頻率），參考章節(jié)12.2.1中的闡述。</p><p><b>　　裝運的凈需求，即</b></p><p>　　dN=在下述運輸周期和訂貨至交貨期內(nèi)的目的地預期需求</p><p><b>　　+目的地的安全庫存</b><

87、;/p><p>　　./.目的地現(xiàn)有庫存</p><p>　　拉式系統(tǒng)中，要是貨源地有足夠的庫存以提供所有的目的地，那么此時的裝運量就可被設定為dN。這個數(shù)量可能會隨著車載步驟而更改，如下所述，如果貨源地庫存不足，貨物將按“平分”原則被分配到目的地，在這里，“平</p><p>　　分”原則需要考慮到每一個目的地的需求和庫存情況，也因此物流需要全球性的信息和中央控制（參

88、見《銀證》等（章節(jié)12.4.3，1998年））。平分的基本思想就在于平衡不同地點對庫存的需求直到貨源得到新的補充。</p><p><b>　　車輛載貨</b></p><p>　　裝運量的預先計算應該依照不同的貨品而進行。他們并未將許多貨品的聯(lián)運考慮進適當?shù)倪\輸單位（如，全托盤）。這是車輛裝載的任務，他們的目的便是將裝運量在車輛的載貨范圍內(nèi)分擔。至于這個數(shù)量代表著凈

89、需求，他們只能增加，但總的來說，需求計算還是可以在建議的量上限定最低量的……</p><p><b>　　車輛調(diào)度</b></p><p>　　正如在上一節(jié)中說明的那樣，車輛調(diào)度只對先進的策劃起著有限的重要性。因此，綜合大量文獻顯示，車輛調(diào)度模型和算法是不適合現(xiàn)今物流形式的。相反，讀者提到了下列評論文章。大多數(shù)文獻關(guān)注的是車輛調(diào)度在倉庫間的啟動和結(jié)束。這個案子以交付來