物流与供应链管理2物流网络构造.ppt
物流与供应链管理2.供应链网络构造,博士(Dr.Houcai SHEN)南京大学,Outline,供应链网络构造What is it?MethodologyModelingData AggregationValidationSolution Techniques,Decision Classifications,Strategic Planning:Decisions that typically involve major capital investments and have a long term effect1.Determination of the number,location and size of new plants,distribution centers and warehouses2.Acquisition of new production equipment and the design of working centers within each plant3.Design of transportation facilities,communications equipment,data processing means,etc.,Decision Classifications,Tactical Planning:Effective allocation of manufacturing and distribution resources over a period of several months1.Work-force size2.Inventory policies3.Definition of the distribution channels4.Selection of transportation and trans-shipment alternatives,Decision Classifications,Operational Control:Includes day-to-day operational decisions1.The assignment of customer orders to individual machines2.Dispatching,expediting and processing orders3.Vehicle scheduling,2)供应链网络构造,苏宁目前的战略任务,网络战略规划部主要问题：在全国构建物流网络，以支持苏宁的战略确定合适的仓库数量；确定每个仓库的规模确定客户从那个仓库收到货物,The Logistics Network,The Logistics Network consists of:Facilities:Vendors,Manufacturing Centers,Warehouse/Distribution Centers,and CustomersRaw materials and finished products that flow between the facilities.,Supply,Sources:plantsvendorsports,RegionalWarehouses:stocking points,Field Warehouses:stockingpoints,Customers,demandcenterssinks,Production/purchase costs,Inventory&warehousing costs,Transportation costs,Inventory&warehousing costs,Transportation costs,Network Design:Key Issues,Pick the optimal number,location,and size of warehouses and/or plantsDetermine optimal sourcing strategyWhich plant/vendor should produce which productDetermine best distribution channelsWhich warehouses should service which customers,Network Design:Key Issues,The objective is to balance service level against Production/purchasing costsInventory carrying costsFacility costs(handling and fixed costs)Transportation costsThat is,we would like to find a minimal-annual-cost configuration of the distribution network that satisfies product demands at specified customer service levels.,Network Design Tools:Major Components,MappingMapping allows you to visualize your supply chain and solutionsMapping the solutions allows you to better understand different scenariosColor coding,sizing,and utilization indicators allow for further analysisDataData specifies the costs of your supply chainThe baseline cost data should match your accounting dataThe output data allows you to quantify changes to the supply chainEngineOptimization Techniques,Mapping Allows You to Visualize Your Supply Chain,Displaying the Solutions Allows you To Compare Scenarios,Data for Network Design,1.A listing of all products2.Location of customers,stocking points and sources3.Demand for each product by customer location4.Transportation rates5.Warehousing costs6.Shipment sizes by product7.Order patterns by frequency,size,season,content8.Order processing costs9.Customer service goals,产品数据,一般产品类型繁多，数据量大不容易有效处理通常采用分类汇集处理(Aggregating)将产品分为几个可处理的产品组将产品的数据换成产品组的数据降低数据的变化（方差）研究指出误差不大与1%,产品的需求量,顾客的数量大和空间分布广直接使用顾客的数据不现实采用数据汇集的方法处理将服务区分为很多小格将格内的顾客需求数据相加汇集成一个数据,运输成本,用运输费率与运输距离来估计运输成本=运输费率*距离距离越长，运输费用也越大同一条线，来回成本可能不一样运输费率与下列因素有关产品类型，包装方式整车与零担距离距离估计运输距离=115*SQRT（纬度差2+经度差2)运输成本估计运输成本=*运输费率*运输距离城市里，=1.3；其它，=1.14,仓库成本,搬运成本包含人工和工具成本与仓库的年流量成比例储存成本带表库存保管成本与平均库存水平成比例固定成本与仓库的规模成比例(但不是正比),储存成本的估计,难处不容易估计每个产品的平均库存解决方案用库存周转率来估计产品平均库存=产品的年流量/产品的库存周转率产品的储存成本=单位储存成本*产品平均库存,固定成本的估计,估计仓库容量利用库存周转率计算平均库存量仓库容量=*2*平均库存量 1，来加上非库存空间的影响估计固定成本查表,仓库选址考虑的因素,与目标顾客的距离一天能往返的路程为佳(450KM的半径)地理和基础设施的条件自然资源和劳动力的可获得性当地产业和税收的法规公众利益政府的优惠条件,顾客服务水平,选择指标可以衡量的实际业务绩效指标与直接发生在交货过程的顾客服务服务水平的指标缺货水平订货提前期大小与稳定程度其它重要顾客服务不与考虑服务水平与成本的关系服务水平越高，成本越大解决出路制定不同的服务水平按顾客的重要程度按产品的重要程度,A Typical Network Design Model,Several products are produced at several plants.Each plant has a known production capacity.There is a known demand for each product at each customer zone.The demand is satisfied by shipping the products via regional distribution centers.There may be an upper bound on total throughput at each distribution center.,A Typical Location Model,There may be an upper bound on the distance between a distribution center and a market area served by itA set of potential location sites for the new facilities was identifiedCosts:Set-up costsTransportation cost is proportional to the distanceStorage and handling costsProduction/supply costs,Complexity of Network Design Problems,Location problems are,in general,very difficult problems.The complexity increases with the number of customers,the number of products,the number of potential locations for warehouses,and the number of warehouses located.,Solution Techniques,Mathematical optimization techniques:1.Exact algorithms:find optimal solutions2.Heuristics:find“good”solutions,not necessarily optimalSimulation models:provide a mechanism to evaluate specified design alternatives created by the designer.,例子,一个产品，两个工厂，两个仓库，三个零售店,生产能力,市场需求,物流成本,经验寻优法的例子#1,应用规则选择配送成本最低的仓库来满足每个市场,物流成本,解决方案,总成本=2*50000+1*100000+2*50000+2*60000+5*140000=1120000,经验寻优法例子#2,应用规则对每个市场，选择进仓库的总运输成本最低的仓库,解决方案,总成本=3*50000+5*900000+2*60000+1*100000+2*50000=920000,经验寻优法的特点,简单可操作性强解决速度快不保证最优，但求较好方案适合作估计值数据量大的情况,数学规划法的解决方案,利用线性规划的方法确定目标函数确定限制条件应用专门软件求解Microsoft Excel线性规划软件特点适合数据量适中的问题解决方案与数学模式有关错的模式，错的结果不是动态的方案适和静态的方案,数学规划法的例子,仿真模拟法,方法根据实情建立一个计算机模型可以很复杂计算机反复模拟生成结果特点比较接近现实开发时间长可用于方案比较,物流网络构造的小结,构造物流网络制定服务水平目标重点顾客，重点产品优先保证收集数据应用汇集数据的方法，减少分析难度解决问题的技术有三经验寻优法数学规划法仿真模拟法,
