1、物流与供应链管理 2. 供应链网络构造,沈厚才 博士(Dr. Houcai SHEN) 南京大学 http:/ What is it? Methodology Modeling Data Aggregation Validation Solution Techniques,Decision Classifications,Strategic Planning: Decisions that typically involve major capital investments and have a long term effect1. Determination of the number,
2、 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:
3、 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-
4、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:
5、Facilities: Vendors, Manufacturing Centers, Warehouse/ Distribution Centers, and CustomersRaw materials and finished products that flow between the facilities.,Supply,Sources: plants vendors ports,Regional Warehouses: stocking points,Field Warehouses: stocking points,Customers, demand centers sinks,
6、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 plants Determine optimal sourcing strategy Which plant/vendor should produce wh
7、ich product Determine best distribution channels Which warehouses should service which customers,Network Design: Key Issues,The objective is to balance service level against Production/ purchasing costs Inventory carrying costs Facility costs (handling and fixed costs) Transportation costsThat is, w
8、e 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,Mapping Mapping allows you to visualize your supply chain and solutions Mapping the solutions allows you to
9、 better understand different scenarios Color coding, sizing, and utilization indicators allow for further analysis Data Data specifies the costs of your supply chain The baseline cost data should match your accounting data The output data allows you to quantify changes to the supply chain Engine Opt
10、imization 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 products 2. Location of customers, stocking points and sources 3. Demand for each product by customer location 4. Transportation
11、 rates 5. Warehousing costs 6. Shipment sizes by product 7. Order patterns by frequency, size, season, content 8. Order processing costs 9. 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
12、 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
13、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
14、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 produc
15、ts 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 it A set of potential location sites for the new facilitie
16、s was identified Costs: Set-up costs Transportation cost is proportional to the distance Storage and handling costs Production/supply costs,Complexity of Network Design Problems,Location problems are, in general, very difficult problems. The complexity increases with the number of customers, the num
17、ber 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 optimal Simulation models: provide a mech
18、anism 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*
19、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,
