生产计划chap1

1、Production Planning and Control,Department of Industrial Engineering (2) the whole production unit can be influenced once an equipment breakdown; (3) low production flexibility,The organization of production system,object specialization,process specialization,3. Group technology (cellular) allocate

2、different equipments into a production cell to work on a product family that have similar shapes and process requirements. Within one cell: the production of a product family can be completed by different type workers using different type equipments.,The organization of production system,Advantages

3、： （1）better human relations. A work team complete a whole task. （2）improved operator expertise. Worker only make limited type parts，repetition means quick learning. （3）Less in-process inventory and material handling. A cell include several production stages, like a production line. （4）faster product

4、ion setup. similar products, fewer tool changes, so fewer setup. GT production cell overcomes some disadvantages of process specialization production,The organization of production system,warehouse,warehouse,warehouse,warehouse,customer,Process specialization vs. GT production cell, process speciali

5、zation, group cell,interval flow line,1.4 Operations Management The level of investment; The measures of allocating resources to and integrating separate business; Functional area strategies, including The marketing strategy; The financial strategy; The operational strategy;,Business Strategy and Op

6、eration Strategy,The definition of Operation Strategy The means by which a firm configures its resources to achieve its competitive goals; For manufacturing firms, it involves all decisions concerning the production, storage, and distribution of goods; Key operational decisions include： Where to loc

7、ate new manufacturing facilities; How large these facilities should be; What processes to use for manufacturing and moving goods through the system; What workers to employ.,Operation Strategy Framework(1),Two Traditional Strategic Dimensions Lower Cost New entrants to a market operate on low cost st

8、rategy; Examples: Korean automakers: Hyundai and Daewoo; Discount outlets: Costco; Retailers: Wal-Mart; May be successful over short term, but risky in long run-low costpoor quality; Product Differentiation Providing uniqueness to buyers : BMW-high performance, well made cars;even high price ; Produ

9、ct differentiation within a firm to capture different market segments: GM-a successful case; Henry Ford as opposite case.,Operation Strategy Framework(2),Other Strategic Dimensions Quality; Delivery speed; Delivery reliability; Flexibility;,Operation Strategy Framework(3),Other Strategic Dimensions

10、Quality; Delivery speed; Delivery reliability; Flexibility;,Operation Strategy Framework(4),Other Strategic Dimensions Quality; Delivery speed; Delivery reliability; Flexibility;,Operation Strategy Framework(5),Other Strategic Dimensions Quality; Delivery speed; Delivery reliability; Flexibility;,1.

11、6 The Classical View of Operation Strategy (1),Traditional view of manufacturing strategy was put forward by Wickman Skinner of the Harvard Business School ; Traditional view considers most strategic issues in the context of plant, rather than entire firm; Classical view, although a bit old-fashione

12、d, is yet important; Classical operation strategy relates to the following issues Time horizon Focus Evaluation Consistency,The Classical View of Operation Strategy Decision Time Horizons,Decision Time Horizons refer to the length of time required for the strategy to have impact on.,Fig1-1 Decision

13、Time Horizons of Manufacturing Strategy,Impacts of Short-term OS are measured in terms of days or even hours; Include purchasing, production policies for control of quality and maintenance function, short-term inventory control,Impacts of medium-range OS are measured in terms of weeks and months; In

14、clude demand and requirement forecasting, employment-planning (size ,Strategy is usually associated with long-term decision ; Include choosing the timing, the location, and the scale of new manufacturing facilities; addressing groundwork for building proper channel for sales and distribution; and se

15、tting up service objects,The Classical View of Operation Strategy Decision Time Horizons,Effects of time horizons on strategy Impact on decision; The uncertainties on decisions; Penalty for wrong decisions.,Example: The Gap (1) Short time horizons involve many decisions, each of whose impact may be

16、small, but cumulatively can make difference. Manager at the Gap store restock shelves and reorder every days. Small errors in sales data and personal judgment required for reordering mix of items may result in out-of-stock or wasted shelf space.,(2) Buyers in San Francisco headquarters of the Gap de

17、cide on what lines of clothes to stock for the coming seasonsMedium-range decision. Less information available than store mangers for the decision; The decisions may have greater impact; They have to judge fashion trends and the color preference.; Penalty: A line that does not sell must be on sale a

18、t lower price.,(3) Top management must make long decisions, possibly (a) the number, location, and size of distribution centers; (b) terms and conditions of long-term contracts with suppliers;(c) arrangements for firm-wide supply chain logistics; (4) selection of management personnel. More uncertain

19、ties: Demographic change makes decision on (a) wrong; a long-term contract with a oversea plant may have opposite results, e .g. quaota, tariffs.,The Classical View of Operation Strategy - Focus,Process Technologies A natural means of focusing operation of one plant; New unproven process technologie

20、s should be limited to one per factory; The number of different mature process technologies should be kept to the level that the plant manager can oversee efficiently.,Notion of focus in manufacturing strategy was first put forward by Skinner. Five key characteristics: (1) Process technologies (2) M

21、arket demand (3) Product volumes (4) Quality levels (5) Manufacturing tasks,Market demands Marketplace usually determines the focus of a product or line of products; Indications of market on plant focus are Price-It has been always a key product differentiation factor; Lead time-It should be shorten

22、ed for quick production and distribution of product fight against competitors. Reliability-Its specifications differ by market segment, even for identical products.,Product volumes-The production volumes within a single plant should be similar for the production systems to be able to operate smoothl

23、y, neither under nor- over utilized.,Quality level Similar quality level of a products produced in a single plant; Consistent quality control standard;,Manufacturing tasks Productivity of a plant producing a wide line of different products are affected by frequent setup and reconstructing of product

24、ion lines. The number of distinct manufacturing tasks at one location should be limited so that workers may concentrate on perfecting exiting processes.,The Classical View of Operation Strategy Evaluation,Dimensions for evaluating production/operations strategy Costif pricing is a key to market diff

25、erentiation and competitiveness, the cost of product delivered to the customer becomes a major means of strategy evaluation. Qualitywhen product quality is a major determinant of product success in marketplace, or high reliability is required to meet product specifications, quality should be a dimen

26、sion for strategy evaluation; Profitability Strategies that achieve short-term profitability may not necessarily be in the best interests of the firm in the long term Customer satisfaction-Maintaining a satisfied and loyal customer base is important for the success of a firm. Customers satisfaction

27、not only in product but also in efficient and cost-effective service after sale are both essential.,The Classical View of Operation Strategy Consistency,Strategy is the composite of all company policies that affect manufacturing; Each may aim at optimizing a different objectives, resulting in a comp

28、lex situation in which management and labors assure adversarial positions. Causes for the common inconsistencies Professionalism-inconsistent goals of different professionals. Product proliferation-a firm that produces a smaller number of products tends to be more profitable, however become less pro

29、fitable as more products are produced within a single plant. Changes in manufacturing tasks-the objectives that made sense when the plant was constructed no longer make sense after the plants function has changed. The manufacturing task was never made explicit.,The Classical View of Operation Strate

30、gy Review,Fig.1-2 The Elements of Production and Operations Strategy,1.7 Strategic InitiativesReengineering the BP,Business Process Reengineering (BPR) is not a specific technique, instead , it is the ideal that business processes can be changed and improved. BPR became popular after the publication

31、 of a book by Hammer and Champy in 1993; BPR can add remarkably values to corporations when implemented intelligently; Example IBM Credit Corporation, a wholly owned subsidiary (affiliated company) of IBM, if independent, may rank among 100 Fortune service companies; Responsible for presenting credi

32、ts to new customers buying IBM equipments;,Strategic InitiativesReengineering the BP,Request,Salesperson,Check credit,Someone in the credit dept.,Modify the documents,A person in business practice dept.,Determine interest rates,Pricer,Form a quote letter,The 5th person,Six days and four peoples(excl

33、usive of the salesperson) are involved in handling each request; Only 90 minutes are actually required for dealing with the request; Other time are wasted either on transiting the request and in query.,Strategic Initiatives Reengineering the BP Strategic,Request,Check credit,Modify the documents,Det

34、ermine interest rates,Form a quote letter,The six-day treatment is shortened to only four hrs; Only one personnel is required; A hundredfold increase in the deals handled;,Strategic Initiatives Reengineering the BP,General principles for BPR (suggested by Hammer and Champy) Several jobs are combined

35、 into one Reducing a complex process requiring many steps into a simpler one with fewer steps. It is BPRs most dramatic successes; Five steps are combined into only one step in the case; Workers make decisions: In order to reduce the number of levels of reporting, workers should be allowed for makin

36、g decision, rather than previously managed. The steps in the process are performed in a natural way: process steps should not be performed in a rigid linear sequence, but in an order that make sense in the context of the problem being solved. Processes should have multiple versions: adaptability may

37、 be obtained by designing a flexible process that can react to different conditions, rather than by designing multiple independent processes; Work is performed where it make the most sense: one of BPRs principle is neither to carry out the idea of division of labor too far; nor to carry out the idea

38、 of centralization too far.,1.9 Strategic InitiativesJust-in-Time (JIT),JIT is both a manufacturing process on one hand and broad-based operation strategy on the other hand; It is a philosophy to treat inventory in the plant, relationship with suppliers and distribution strategy; The core of its phi

39、losophy is to eliminate waste by efficient scheduling of incoming orders, work-in-process (WIP) inventories, and finished goods inventories. Its advantages over conventional systems Reduced cost resulted from eliminating WIP; Enabled quick detection of quality; Tightened up relationship with supplie

40、rs;,1.10 Strategic InitiativesTime-Based Competition,Professor Terry Hill (the London School of Business) Classified competitive factors into “qualifiers” and “order winners. Qualifiers make a firm possible to win orders, but not sure to do; Order winners are factors that determine who will get the

41、sale among the set of qualifiers. Quality has become an order qualifier rather than an order winner as previously. Time-based competition is a key factor leading to success or failure. Time-based competition focus on entire value-delivery system, attempts to transform an organization into one that f

42、ocus on the total time needed for delivering a product or a service. The goal is not to design the best way to perform a task, but to either eliminate the task altogether or perform it in parallel with other tasks in order to reduce overall system response time.,1.11 Strategic InitiativesCompeting o

43、n Quality,Quality is one of the two leading factors (the other one is time management) ; Malcolm Baldrige Awards (USA) and Daming Prize; Quality means different things in different contexts; A high-quality product perform well as it was designed; Products will perform as they are designed to perform

44、, if there is litter variation in manufacturing process; Is it possible for a poorly designed product to perform well? Is is possible for a well designed to perform poorly? Many success stories in US manufacturing shows that firms can compete successfully on the quality dimension. Ford Motor with Ta

45、urus; Stanley Work of New Britain; PC clones: Compaq Computer and Dell Computer Motorola,1.12 Matching Process and Product Life Cycles (1),Product Life Cycle-the time duration from the time when a product is put into market to time when it disappear in the market; A typical product life cycle consis

46、t of four major segments: Start up Rapid growth Maturation Stabilization or decline;,Fig.1-3 The Product Life Cycle Curve,Matching Process and Product Life Cycles (2),Matching Process and Product Life Cycles(3),The Product life cycles-in different phases, different competition strategy may be adopte

47、d Start upthe competition is generally not a problem; concern on improvement of the production and marketing functions; Rapid growthbegin to see competition; establish the product as firmly as possible in the marketplaces by alternative pricing patterns, improvement and standardization in manufactur

48、ing; Maturationmaintain and improve the brand loyalty; increase market share through competitive pricing; save cost by improving production control and product distribution; The final phasethe shape depends on the nature of the product: indefinite continuing growth (household goods, processed foods,

49、 and auto)/same strategy as Phase 3; natural decline/squeezing out the most from the product or product line.,Matching Process and Product Life Cycles （4）,The Process Life Cycle three major stages of the manufacturing process life cycle Early stage job shop; a varied mix of relatively low-volume ord

50、ers; being responsive to changes in the product design; little control over suppliers; Middle stage some automation; batch process and some transfer lines(assembly lines); more control over suppliers; unit cost decline; Last stage automated process and standardized production process; few manufactur

51、ing innovation; continuous flow operation.,Matching Process and Product Life Cycles（）,The Product-Process Matrix (PPM) (Hayes Firms choosing to operate on off the diagonal should clearly understand the reason for doing so.,Matching Process and Product Life Cycles（）,Fig.1-4 The Product-Process Matrix

52、,Ship Building,Coffee bar,Located in the upper left corner are companies that specializes in “one-of-a-kind” jobs in which manufacturing has the characteristics of a jumbled flow shop. Production is in relatively small lots, and the shop is organized for maximum flexibility.,Farther down the diagona

53、l are firms that still require a great deal of flexibility but produce a limited line of standardized items. A disconnected line would provide enough flexibility.,The 3nd class down the digonal are firms that produce a line standardized products for a larger-volume market. The assembly line would be

54、 an appropriate process technology.,The lower right-hand portion are appropriate for products involving continuous flow line, which are characterized by low cost, standardization of product, high sale volume, and inflexibility of the production process.,Matching Process and Product Life Cycles（）,To

55、identify the proper match of the production processes with the phases of the product life cycle.,Fig.1-5 The Product-Process Matrix,In the start-up phase of product development, the company would typically be positioned on the upper left-hand corner of the matrix; As the market for the product matur

56、es, the firm would move down the diagonal to achieve economies of scale; Finally, the firm would settle at the position on the matrix that would be appreciate based on the characteristics of the product.,1.13 Capacity Growth Planning a long-term strategy problem (1),Capacity of a plant is the number

57、 of units that it may produce in a given time; Factors to be considered for capacity strategy: Predicated patters of demand; Costs of constructing and operating new facilities; New process technology; Competitors strategy Each time a company considers expanding existing productive capacity, it must

58、compare all the possibility-Whether to do by modifying the existing facility? May be cheaper, however may be penny wise and pound foolish.,Capacity Growth Planning a long-term strategy problem (2),Issues needed to be considered for constructing a new pant When to construct? Two affecting factors-con

59、struction lead times and changing patterns; Where to build? Near suppliers or market outlets? Where labor cost or tax lower? What size? Underutilized or shortage of capacity.,Capacity Growth Planning a long-term strategy problem (2),Economies of Scale and Economies Scope Economies of Scale is considered the primary advantages of expanding existing capacity. Economies of Scope, introduced by Panzer and Willig, is defined as the cost savings obtained from combining the production of two or more pr