年月庫存管理串講（Novemberinventory management）

1、2010年11月庫存管理串講（November 2010 inventory management）Chapter 1 inventory management overviewI. Basic concepts of inventory management1. definition of inventory: inventory refers to temporarily idle resources for future purposes. (fifth pages)2. inventory function: (page 6-9) (Mastering)Inventory enable

2、s enterprises to achieve economies of scaleInventory balances supply demandInventory can prevent uncertainty, random fluctuation of demand, and uncertainty of order cycleInventory plays a buffer role in the supply chainInventory can eliminate the difference in geographical position between the suppl

3、y and demand sides3. the basic objective of inventory (page 10-11): to meet the anticipated demand with the lowest inventory cost under the existing resources of the enterprise.Two. Inventory classification and inventory cost1. inventory problems in different enterprises (pp. 11-12)Retail enterprise

4、s, wholesale enterprises, manufacturing enterprises2. classification of inventories (P. 12-15)(I) the status of the inventory goods in the production process and distribution processRaw material inventoryWIP inventoryMaintenance stockFinished product inventory(two) classification according to the ro

5、le of inventory (requirements: understanding the definition of each inventory);Circulating inventory: inventories formed by periodic quantities.Safety inventory: the utility model is used to compensate the demand that the actual demand exceeds the expected demand or the actual order lead time exceed

6、s the expected lead time when the supply in the lead time is added.Adjusting inventory: the inventory that is used to adjust the imbalance of demand or supply, imbalance between production speed and supply speed and unbalanced output at each stage of production.Inventory in transit: goods that are t

7、ransported from one place to another in transit.Three. Composition of inventory costs (page 16-17)Acquisition cost: when the product is purchased from the outside, the purchase cost refers to the product of the unit purchase price and the purchased quantity; when the product is made in the enterpris

8、e, it means the product of the unit production cost and the production quantity.Order cost (or order cycle): the cost of obtaining goods or raw materials through procurement or other means from the confirmation of the requirements to the eventual arrival of the goods.Storage (storage) cost: harvesti

9、ng, storage and handling expenses, etc.Shortage cost: the cost of supply due to external or internal disruptions.Requirements: understand the meaning of the costs, including the specific contentFour: inventory management process (page 23-27)Identifying requirements: Requirements Identification and d

10、emand forecastingInventory identification and codingDetermination of order quantity and order timeDetermination of service level and safety stockProcurement lead time management (key understanding)Lead time: refers to the time interval from the order delivery to the receipt of the goods, including i

11、dentification of stock, confirmation, replenishment of inventory, contact with suppliers, signing orders, prompt delivery and arrival and inspection time.2. basic decisions on inventory control (twenty-eighth pages)The basic decisions of inventory control are important, including the following:Deter

12、mine the time interval between two adjacent ordersDetermine the order quantity of each orderDetermine the lead time for each orderDetermine the service rate of inventory to meet the demandThe second chapter inventory demand forecasting1. definition of prediction (thirty-ninth pages): prediction and

13、speculation of an uncertain or unknown event.2. classification of forecasts (page 40-42)The role of classification by subjective and objective factors playQuantitative method; qualitative methodAccording to the length of time predictionLong term prediction; medium-term prediction; short-term predict

14、ionTable 2-1 (forty-first pages)Requirements: to understand the contents and methods.3. requirements forecast (page 42-45)QuantityTimeFrequencyScopePredictability4. factors affecting demand (pp. 46-47), figure 2-31, the business cycle. 2. product life cycle. 3. customer purchasing power, customer pr

15、eferences. 4 advertising, promotional capabilities, reputation, product arrangement, design and so on.Key understanding: product life cycle, figure 2-4Requirement: MasteryQualitative prediction method1. qualitative forecasting method (page 50-53)General forecastMarket ResearchGroup consensusHistoric

16、al analogyDelphy FaRequirements: the main understanding of market research and the operation of Delphy Fa and its advantages and disadvantages, Delphi method must adhere to the 3 principles (fifty-third pages)Principle 1, anonymity. 2, feedback. 3, convergence.Quantitative prediction method1. time s

17、eries analysis (page 53-57)Simple average methodWeighted average methodSimple moving average methodRequirements: look at the textbook examples, understand the calculation formula, and can be calculatedPredictive monitoring1. the cause of the error (seventy-second pages)The unknowable future. Errors

18、may come from many sources, a common source of extrapolating past trends to future processes, which many forecasters often fail to realizeErrors are unavoidable in prediction, and the difference between the actual and the predicted values is usually defined as the error of the predicted value2. meas

19、urement of error accuracy (seventy-third pages)Average errorMean absolute errorRequirements: master methods of calculation and calculationsNote: only one average error value can be calculated in a given set of dataThe third chapter inventory control modelFixed order quantity system1. operation mecha

20、nism (eighty-third pages)Fixed order quantity system is also called continuous system or quantitative order system. In this system, the inventory balance should be compared with the order point at any time to decide whether to place an order or not.The operating mechanism is: when the inventory bala

21、nce falls to the order point, a fixed quantity order is issued.2. fixed order quantity system model concept (page 84-85) order point and order quantity fixed inventory control system.3. the characteristics of the fixed order quantity system, 3 points (eighty-fifth pages) in the textbookFeatures: 1,

22、each order quantity is usually fixed. 2, the time interval between two adjacent orders is usually varied. 3 the lead time of the order is basically unchanged. 4, the key is the determination of order quantity and the establishment of order warning line.Two. Fixed interval system1. operation mechanis

23、m (page 88-89)Fixed interval system is also known as the periodic inventory system, the operation mechanism for every fixed time check inventory, determine the inventory balance and send out an order, the order quantity is equal to the maximum amount of inventory and inventory balance difference.2.

24、fixed interval system model (page 89-90)The order time is fixedThe order quantity is variable3. max min system (page 90-91)The system is determined by three variables, the inspection period T, the maximum inventory E and the order point R.The operation process is: check the stock every fixed time, a

25、nd determine the inventory balance. When the inventory balance is less than or equal to the ordering point, the order is issued, and the order quantity is equal to the difference between the maximum inventory and the inventory balance.The fourth chapter is quantitative analysis of inventory control

26、decisionOne.ABC classificationFundamentals of 1.ABC classification (105th pages)Classify according to the value or importance of the object under control, usually divided into three categories according to annual consumption amount (inventory value or quantity * cost). A class of stock varieties acc

27、ounted for about 10 of the total varieties, but the value of inventories accounted for the total price of 70%, the B class of items in the inventory total species accounted for 20% of the total variety, the total value of the inventory value accounted for about 20%, C stock varieties accounted for a

28、bout 70% of the total value of goods, the total value of inventories accounted for about 10%.2. classification methods: table 4-1 (105th pages)The basis of the 3.ABC classification (106th pages)They are usually classified according to their annual value4.ABC classification inventory policy (107th pa

29、ges), Table 4-2, class a tight control, class B general control. C class free processing.Requirements: Master inventory control strategies for different categories of inventoryTwo.Economic order quantity1. the relation between the order quantity and the cost of the three (116th pages)Figure 4-4 rela

30、tionship between order quantity and cost: Master2. assumptions for determining the economic order quantity (115th pages): Understanding3. calculations (page 117-118)Formulas and examples 4Requirements: master and able to perform calculations4. sensitivity of economic order quantities (118th pages)Re

31、quirement: UnderstandingThree. Economic order interval1. definition (page 123-124)The economic period is to make the total inventory cost of the lowest order interval in order system, the economic order interval decides a certain number of items or when issued orders, or orders are carried out at fi

32、xed period of time.2. calculations (page 124-125)Formulas and examples 8Requirements: understand the formulas and calculate themFour. Safety stock and order point1. definition and function of safety stock (page 127-129): UnderstandingA: the definition is used to compensate for the actual demand in t

33、he supply lead time exceeds the expected demand or actual lead time exceeding the expected lead time.Function: 1. with warehouse and retail with safety stock is in user demand rate of irregular or unpredictable circumstances have the ability to supply them.2 the factory finished product warehouse ho

34、lds safe stock to replenish their inventory in order to exceed the expected value of the retail and transit warehouse requirements.3, if there is no safe stock, there will be a shortage when demand exceeds the expected value in the lead time.The fifth chapter is about the problems of inventory manag

35、ementInventory management of new equipment spare parts1. new spare parts inventory features (150th pages)New equipment is purchased and used, and the damage to its components and components is unknown. Before determining the use of new equipment, the initial supply that can maintain its maintenance

36、and repair must be determined.The determination of the initial supply of new equipment is usually based on the manufacturers recommendations.2. reverse logisticsThe concept of reverse logistics (page 152-153)Using inventory traceability, we can process and calculate returns, which is reverse logisti

37、cs. Reverse logistics covers all activities involved in reusing materials and goods, collecting, removing and treating used products, parts, or raw materials so that they are effectively utilized.The American Association of logistics reverse logistics under the definition: in order to recycling or d

38、isposal of waste in efficiency and cost is appropriate, the flow and storage of raw materials, semi-finished goods, finished goods and related information from the point of consumption to the original output point, planning, management and execution of process pipe.Recovery Logistics and scrap logis

39、tics belong to reverse logistics.3. handling of superfluous articlesThe concept of superfluous goods (155th pages)Waste material, surplus material, old material2. identification of excess items (156th pages)3. how to reduce inventory (page 157-159)Circulating inventory: reduce order cost, shorten op

40、eration exchange time, and increase production quantity by similarity.Safety stock: order time as close as possible to demand time and order quantity as close as possible to demand. Improve demand forecasting, shorten production cycle and order cycle. Reduce the instability of supply. Increase flexi

41、bility of equipment and personnel.Adjust stock: make the speed of production accord with the change of demand.Inventory in transit: shorten production and delivery cycle.Table 5-2Requirements: understand specific measures to reduce inventory, focusing on cycle stock and safety stock.4. inventory acc

42、uracy and stock taking1. definition of inventory accuracy (159th pages)Answer: refers to the inventory record and the actual inventory of the degree of conformity.2. method of determining inventory accuracy (159th pages)Requirements: inventory records must be accurateCheck stock regularly3. causes o

43、f inaccurate stock (160th pages)Distribution delays, sales declineDelaying the release of production orders - resulting in delays in production and deliveryExcessive inventory formation - increased operating capitalIncrease the resources needed for accelerated replenishmentThe sixth chapter is inven

44、tory management of related demandOverview of 1.MRPThe concept of 1.MRP (174th pages)Material requirements planning (MRP) is the system that calculates the raw materials, parts, and components used to produce the final product. The basic form of MRP is a computer program, according to the final produ

45、ct total production schedule stipulated in the delivery date, determines the required material for production of various products specified number within a specified period of time (composed of the assembly, final product components and parts) number and time.Application of 2.MRP (page 175th) table

46、6-1 requirements: UnderstandingThe emergence and development of 3.MRP (page 176th) requirements: Understanding4.MRP input (page 180-185)Master production scheduling is a comprehensive plan, which is the main input of MRP, which is equivalent to the product production schedule, and is the driving for

47、ce of MRP operation. Main production planning (MPS); product structure document; inventory status file;Output of 5.MRP (page 185-186)The main output of the document (11 of the textbooks)Order quantity in 2.MRP system1.MRP calculation program (186th pages)2.MRP calculation process (page 189-191) exam

48、ple 1Requirement: master simple MRP calculation3.MRP IIThe concept of 1.MRP II (page 203-204)The difference between 2.MRP II and MRP (204th pages)Answer: 1, different concepts. MRP is the system that calculates the raw materials, parts, and components used to produce the final product. In 1980s, peo

49、ple integrated the production, finance, sales, engineering, procurement and other subsystems into an integrated system, called the manufacturing resource planning system.2, MRP II is the direct result and extension of closed loop MRP.3. different functions. The basic form of MRP is a computer progra

50、m, according to the final product total production schedule stipulated in the delivery date, determines the amount of time required for a variety of materials and production of various products designated number within a specified time. MRP2 has been greatly expanded in content and ability, it cover

51、s the whole enterprise production and management activities, including sales, production, inventory, production planning and control, comprehensive planning and management of all the means of production, inventory, human resources, equipment etc.MRP (material, requirements, planning) material requir

52、ement planningMRP II (manufacturing, resource, planning) manufacturing resource planningThe MRP II system includes cost accounting and financial functions.4.ERPThe core idea of 1.ERP (page 208-210)Embody the idea of managing the whole supply chain resourcesEmbodies the idea of lean production and ag

53、ile manufacturingEmbody the idea of planning ahead and controlling in actionRequirement: UnderstandingThe seventh chapter, JIT and its inventory managementThe philosophy of 1.JIT (228Th pages)Answer: continuous improvement, total quality control, full participation and inventory reduction2.JITs goal

54、 (page 228-229)Inventory only exists when neededImproving quality and realizing zero defectShorten delivery time by reducing preparation time, waiting time and lot sizeElimination of wasteComplete the task with the least costThe basic elements of 2.JIT1. basic elements (229th pages)Eliminate waste,

55、total quality and personnel factors2. waste elimination (page 230-233) common 7 forms of wasteAnswer: 1, excessive waste caused by production. 2. Waste during waiting period. 3, waste caused by transportation. 4, the waste of process is not perfect. 5, inventory accumulation caused by waste. 6, wast

56、e caused by quality defects. 7, lack of overall waste.Requirement: understand 7 kinds of waste, and explain why wasteThreeTotal quality (P. 233-235)1, enterprise top management. 2 、 operation integration. 3, prevent quality defects. 4, product quality inspection. 5 quality self insurance. 6 continuous improvement.JIT inventory1.JIT is the development trend of inventory management (page 238-239)Eliminate waste and meet operational requirements with minimal inventory2. Kanban principleThe types and forms of Kanban (240th pages)Cards, parts boxes, billboards, lights, or