上海海事 供应链 ppt第五章1.ppt

单击此处编辑母版标题样式,*,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,Chapter 5 The Value of Information,5.1 Introduction,5.2 the Bullwhip Effect,5.3 Effective Forecasts,5.4 Information for the Coordination of Systems,5.5 Locating Desired Products,5.6 Lead Time Reduction,5.7 Integrating the Supply Chain,5.1 Introduction,We,live in the“Information Age.”databases,electronic data interchange(EDI),decision-support systems,the Internet,and intranets are just a few of the technologies dominating the business page of the daily newspaper.,The implications of this abundance of available information are enormous.The supply chain pundits and consultants like to use the phrase,In modern supply chains,information replaces inventory.,Information changes the way supply chains can and should be effectively managed,and these changes may lead to,among other things,lower inventories.,We argue here that this abundant information:,Helps reduce,variability,in the supply chain.,Helps suppliers make better,forecasts,accounting for promotions and market changes.,Enables the,coordination,of manufacturing and distribution systems and strategies.,Enables retailers to better serve their customers by offering tools for locating desired items,Enables retailers to react and adapt to supply problems more rapidly.,Enables lead time reductions.,5.2 The Bullwhip Effect,For instance,Figure 4.5 illustrates a simple four-stage supply chain:a single retailer,a single wholesaler,a single distributor,and a single factory.,It is important to identify techniques and tools that will allow us to control the bullwhip effect;that is,to control the increase in variability in the supply chain.,For this purpose,we need to first understand the,main factors,contributing to the increase in variability in the supply chain.,1.Demand forecasting,.,An attractive policy used in practice by each stage of the supply chain is the min-max inventory policy.Here,whenever the inventory position at a facility is less than a given number,referred to as the reorder point,the facility raises its inventory level up to a given target level,called the order-tolevel.,库存订货点理论,最大库存量,订货点,安全库存量,订货提前期,2.Lead time,.,It is easy to see that the increase in variability is magnified with increasing lead time.,With longer lead times,a small change in the estimate of demand variability implies a significant change in safety stock,reorder level,and thus in order quantities.,3.Batch ordering,.,Wholesaler will observe a large order,followed by several periods of no orders,followed by another large order,and so on.Thus,the wholesaler sees a distorted and highly variable pattern of orders.,Firms use batch ordering for a number of,reasons,.,First,a firm that is faced with fixed ordering costs needs to apply the min-max inventory policy,which leads to batch ordering.,Second,as transportation costs become more significant,retailers may order quantities that allow them to take advantage of transportation discounts.,4.price fluctuation,.,Price fluctuation can also lead to the bullwhip effect.If prices fluctuate,retailers often attempt to stock up when prices are lower.,5.inflated orders,.,Inflated orders placed by retailers during shortage periods tend to magnify the bullwhip effect.Such orders are common when retailers and distributors suspect that a product will be in short supply,and therefore anticipate receiving supply proportional to the amount ordered.,When the period of shortage is over,the retailer goes back to its standard orders,leading to all kinds of distortions and variations in demand estimates.,5.2.3 Methods for Coping with the Bullwhip Effect,Reducing uncertainty,.,One of the most frequent suggestions for decreasing or eliminating the bullwhip effect is to reduce uncertainty throughout the supply chain by centralizing demand information;that is,by providing each stage of the supply chain with complete information on actual customer demand.,2,、,Reducing variability,.,everyday low,price(EDLP,),：,When a retailer uses EDLP,it offers a product at a single consistent price,rather than offering a regular price with periodic price promotions.By,eliminationg,pricing that occur along with these promotions.,Therefore,everyday low pricing strategies can lead to much more stable-that is,less variable-customer demand patterns.,3、Lead time reduction,.Observe that lead times typically include two components:order lead times(i.e.,the time it takes to produce and ship the item)and information lead times(i.e.,the time it takes to process an order).,4、Strategic partnerships,.,These strategic partnerships change the way information is shared and inventory is managed within a supply chain,possibly eliminating the impact of the bullwhip effect.,For example,VMI,5.3 Effective Forecasts,Information leads to more effective forecasts.,For example,consider retailer forecasts.These are typically based on an analysis of previous sales at the retailer.However,future customer demand is clearly influenced by such issues as pricing,promotions,and the release of new products.,Similarly,distribution and manufacturer forecasts are influenced by factors under retailer control.,In addition,because a manufacturer or distributor has fewer products to consider than the retailer,he may have more information about these products.,For all of these reasons,many supply chains are moving toward cooperative forecasting systems.,5.4 Information for the Coordination of Systems,Within any supply chain are many systems,including various manufacturing,storage,transportation,and retail systems.,All of these systems are connected.,Two issues need to be addressed:,Who will optimize?,How will the savings obtained through the coordinated strategy be split between the different supply chain facilities?,5.5 Locating Desired Products,Meet customer demand,For example,suppose you go to a retailer to buy a large appliance and it is not available.Perhaps you will go to the retailers competitor down the street.But if the retailer searches a database and promises to have the item delivered to your house within 24 hours.You will probably feel like you have received great customer service,even though the retailer is out of stock of the item you wanted.,5.6 Lead Time Reduction,The importance of lead time reduction cannot be overstated.It typically leads to:,The ability to quickly fill customer orders that cant be filled from stock.,Reduction in the bullwhip effect.,More accurate forecasts due to a decreased forecast horizon.,Reduction in finished goods inventory levels(see chapter 3).This is true because one can stock raw materials and packaging material(or subassembly)inventories to reduce finished goods cycle time.,5.7 Integrating the Supply Chain,Information enables us to integrate the various stages in the supply chain.If the objectives at every stage of the supply chain were complementary,then there would be no need to integrate management of the supply chain.,However,the managers of different stages in the supply chain have conflicting goals,and it is exactly these conflicts which necessitate the integration of the different stages in the supply chain.,This is easier to do in a centralized system,but even in a decentralized system it may be necessary to find incentives to bring about the integration of supply chain facilities.,5.7.1 Conflicting Objectives in the Supply Chain,We begin with the raw material suppliers.,stable volume requirements,Little variation in the mix of required materials,Flexible delivery times,Manufacturing management,JIT,The materials,warehousing,and outbound logistics management also have lists of criteria.These include minimizing transportation costs by taking advantage of quantity discounts,minimizing inventory levels,and quickly replenishing stock.,Finally,to satisfy their customers,retailers need short order lead times and efficient and accurate order delivery.,5.7.2 Designing the Supply Chain for Conflicting Goals,The Lot SizeInventory Trade-Off,As we have seen,manufacturers would like to have large lot sizes.Per unit setup costs are reduced,manufacturing expertise for a particular product increases,and processes are easier to control.Unfortunately,typical demand doesnt come in large lot sizes,so,large lot sizes lead to high inventory,.,The Inventory-Transportation Cost Trade-Off,These is a similar trade-off between inventory and transportation costs.,The Lead Time-Transportation Cost,Total lead time is made up of time devoted to processing orders,to procuring and manufacturing items,and to transporting items between the various stages when large quantities of items are transported between stages of the supply chain.,However,lead times can often be reduced if items are transported immediately after they are manufactured or arrive from suppliers.,.,Thus,there is a trade-off between holding items until enough accumulate to reduce transportation costs,and shipping them immediately to reduce lead time.,In addition,improved forecasting techniques and information systems reduce the other components of lead time,so that it may not be essential to reduce the transportation component,The Product Variety-Inventory Trade-Off,Evidently product variety greatly increases the complexity of supply chain management.Manufacturers that make a multitude of different products with smaller lot sizes find,their manufacturing costs increase and their manufacturing efficiency decreases.,To maintain the same lead times as a company may have had with fewer products,smaller amounts will probably be shipped so warehouses will need to hold a larger variety of products.,Thus,increasing product variety increases both transportation and warehousing costs.Finally,because it is usually difficult to accurately forecast the demand for each product,because all are competing for the same customers,higher inventory levels must be maintained to ensure the same service level.,One way to support the required product variety efficiently is to apply the concept called,delayed differentiation,case,The Cost-Customer Service Trade-Off,Reducing inventories,manufacturing costs,and transportation costs typically comes at the expense of customer service.,We have defined customer service as the ability of a retailer to meet a customers demand from stock.,Review,5.1 Introduction,5.2 the Bullwhip Effect,5.3 Effective Forecasts,5.4 Information for the Coordination of Systems,5.5 Locating Desired Products,5.6 Lead Time Reduction,5.7 Integrating the Supply Chain,