【導讀】采購和采辦這兩個術語盡管其適用范圍確實不同但通常被人們替換使用。購通常指物料的實際購置以及相關的購買活動。交通、倉儲和接受運人物料。采購決策者可比作魔術師，為了實現(xiàn)多種目標常在空中同時拋擲多種球。⑴.為了保證組織的經(jīng)營活動不間斷地提供物料、供應品及服務。⑵.使庫存投資與損失降至最低程度。⑶.保持適當?shù)馁|(zhì)量標準。⑷.尋找并開發(fā)質(zhì)量可靠的賣方。⑸.如有可能，制定出所購項目的標準，使之標準化。⑹.以最低的最終價格購買所需物料和服務。由于購買過程極為復雜，因此制定購買決策時必須考慮。選擇對象；建立關系；設立采購和使用標準；評估購買行為；確定預算的可得性；全是新決策，否則沒有必要履行采購過程的全部12個步驟。式，但多數(shù)公司都為產(chǎn)品采購建立了正式書面材料。們應向供應商提交正確的質(zhì)量采購規(guī)格。購數(shù)量超過當前需求。尋常事情的發(fā)生。有效的超前購買有助于使采購物料的邊際利潤最大化。

　　

【正文】 avings in purchase price and ordering costs is offset entirely by the additional inventory carrying costs. The optimal forward buy would be a five month supply, which would result in savings of $390. However, if the purchasing manager judged solely on the perunit purchase price, he or she would purchase a 12 month supply, at a cost to the firm of $852. 50. That is, purchasing 12 _ month supply would result in decrease in pretax profits of $852. 50. This example illustrates that inventory carrying costs must be included in the forward buying decision. Another disadvantage is the reduction in the firm39。s cash that results from forward buying. Funds expended for inventories are not available for other uses. Therefore, the firm should anticipate future working capital needs before engaging in forward buying. Assumptions: key: 1) Monthly Usage=$2021 $1000 x 30% x 1/12 = $25 2) Expected price increase=10 percent 3) Inventory Carrying Cost = 30 percent $2200/2x 30% x 11/12=$ 4) Ordering Cost = $ 5) Vendor pays the Freight $12021 /2 x 30% x 12/12=$3600 Cost trade _ offs are a key to successfully managing die purchasing function. By thinking in terms of the coat trade offs, management should minimize the total of those costs rather than attempt to minimize the cost of either ponent. This is critical, as attempts to reduce individual costs may in fact actually increase total costs. Just in Time Systems Kanban and Just in Time systems have bee much more important in manufacturing and logistics operations in recent years. Kanban, also known as the Toyota Production System (TPS), was developed by Toyota Motor Company during the 1950s and 1960s。 Kanban is basically the system of supplying parts and materials just at the very moment they are needed in the factory production process so those parts and materials are instantly put to use. While the technique is most often associated with the automobile industry, it can apply to any manufacturing process involving repetitive operations. An expansion of Kanban are JustinTime (JIT) systems. JIT links purchasing and procurement, manufacturing, and logistics. Its primary goals are to minimize inventories, improve product quality, maximize production efficiency, and provide optimal customer service levels. It is basically a philosophy of doing business. JIT has been defined as: A tool to integrate and control the entire process of steps by which materials are transformed into products. Included in this process are the functions of supplier and source selection, transportation, storage and inspection, manufacturing, and quality control. The system specifies what should be stored, moved, produced, or inspected and precisely when it should be done. At the heart of JIT system is the notion that anything over the minimum amount necessary for a task is considered wasteful: waste is considered anything other than the absolute minimum resources of material, machines, and manpower required to add value to the product. This is in direct contrast to the traditional philosophy of just in case, in which large inventories of safety stocks are held in event they are needed. In the case of JIT, the ideal lot size or EOQ is one unit, safety stock is considered unnecessary, and any inventory should be eliminated. Perhaps the best known example of Kanban and JIT systems is the approach developed by Toyota. Through reduction of inventories, Toyota identified problems in supply and product quality, because problems were forced into the open. Safety stocks were no longer available to overe supplier delays and faulty ponents, thus forcing Toyota to eliminate “hidden production and supply problems. It is the same type of procedure that, in recent years, has been applied in many panies in the United Slates. The evident advantages of the system are as follows: increased inventory turnover ratio for raw materials and goods in process。 in production setup times by more than 75%。 reduction in assembly line stock outs。 inventory costs reduced largely。 reductions in defect and warranty claims by customers. Not every ponent can be handled by the Kanban or JIT approach, but for items that are used repetitively and are not bulky or irregular in shape, die systems work well.