约束理论TOC毕业论文外文翻译

1、附录atheory of constraintan output of a system that identifies the need for and the type of action to be taken to correct a current or potential problem. examples of action messages in an mrp system include release order, reschedule in, reschedule out, and cancel. in constraint management, the use of

2、nonconstraint resources to make parts or products above the level needed to support the system constraint(s). the result is excessive work-in-process inventories or finished goods inventories, or both. in contrast, the term utilization is used to describe the situation in which nonconstraint resourc

3、e(s) usage is synchronized to support the needs of the constraint.1) the classification of quantities of items that have been assigned to specific orders but have not yet been released from the stockroom to production. it is an uncashed stockroom requisition. 2) a process used to distribute material

4、 in short supply.2) a routing, usually less preferred than the primary routing, but resulting in an identical item. alternate routings may be maintained in the computer or off-line via manual methods, but the computer software must be able to accept alternate routings for specific jobs.the percentag

5、e of time that a worker or machine is capable of working. the formula is availability = (s - b)*100% / swhere s is the scheduled time and b is the downtime. the volume/mix of throughput on which financial budgets were set and overhead/burden absorption rates established.in the theory of constraints,

6、 a process in which all expediting in a shop is driven by what is scheduled to be in the buffers. by expediting this material into the buffers, the system helps avoid idleness at the constraint and missed customer due dates. in addition, the causes of items missing from the buffer are identified, an

7、d the frequency of occurrence is used to prioritize improvement activities.a material of value produced as a residual of or incidental to the production process. the ratio of by-product to primary product is usually predictable. by-products may be recycled, sold as is, or used for other purposes. th

8、e capability of a system or resource to produce a quantity of output in a particular time period. the process of measuring production output and comparing it with the capacity plan, determining if the variance exceeds preestablished limits, and taking corrective action to get back on plan if the lim

9、its are exceeded. inventory decision making exercised at each stocking location for skus at that location.an amount of inventory kept between entities in a manufacturing or distribution network to create independence between processes or entities. the objective of decoupling inventory is to disconne

10、ct the rate of use from the rate of supply of the item.the locations in the product structure or distribution network where inventory is placed to create independence between processes or entities. selection of decoupling points is a strategic decision that determines customer lead times and invento

11、ry investment. see: control points.a work center that is designated to produce a single item or a limited number of similar items. equipment that is dedicated may be special composite part.equipment or may be grouped general-purpose equipment committed to a in the theory of constraints, the generali

12、zed process used to manage resources to maximize throughput. the drum is the rate or pace of protection against uncertainty so that the system can maximize throughput. production set by the systems constraint. the buffers establish the the rope is a communication process from the constraint to the g

13、ating support the constraint. operation that checks or limits material released into the system to products whose customer specifications require unique engineering design, significant customization, or new purchased materials. each customer order results in a unique set of part numbers, bills of ma

14、terial, and routings. a situation where the output capabilities at a nonconstraint resource exceed the amount of productive and protective capacity required to achieve a given level of throughput at the constraint.a method of inventory valuation for accounting purposes. the accounting assumption is

15、that the oldest inventory is the first to be used, but there is no necessary relationship with the actual physical movement of specific items.of range and time, to external or internal changes. six different 1) the ability of the manufacturing system to respond quickly, in terms categories of flexib

16、ility can be considered: mix flexibility, design changeover flexibility, modification flexibility, volume flexibility, rerouting flexibility, and material flexibility. in addition, flexibility involves concerns of product flexibility. flexibility can be useful in coping with various types of uncerta

17、inty. 2) the ability during periods of increasing or diminishing volume.of a supply chain to mitigate, or neutralize, the risks of demand forecast uncertainty, and transit time plus customs-clearance time uncertainty variability, supply continuity variability, cycle time plus lead-time a procedure f

18、or building process train schedules that starts with the first stage and proceeds sequentially through the process structure until the last stage is scheduled.a work center that performs the first operation of a particular routing sequence.the capacity generally not used in a system of linked resour

19、ces. from a capacity and excess capacity. the branch of accounting dealing with valuing inventory. inventory may be recorded or valued using either a perpetual or a periodic system. a perpetual inventory record is updated frequently or in real time, while a periodic inventory record is counted or me

20、asured at fixed time intervals, e.g., every two weeks or monthly. inventory valuation methods of lifo, fifo, or average costs are used with either recording system.inventory used to protect the throughput of an operation or the schedule against the negative effects caused by delays in delivery, qual

21、ity problems, delivery of incorrect quantity, and so on.the dollars that are in all levels of inventory.a statement of a companys goals and approach to the management of inventories.coordinating the lot sizing and order release decision for related items and treating them as a family of items. the o

22、bjective is to achieve lower costs because of ordering, setup, shipping, and quantity discount economies. this term applies equally to joint ordering and to composite part fabrication scheduling. a method of inventory valuation for accounting purposes. the accounting relationship with the actual phy

23、sical movement of specific items. the process of, or techniques used in, determining lot size.dividing a lot into two or more sublots and simultaneously processing each sublot on identical facilities as separate lots, usually to compress lead time or to expedite a small quantity. a number that ident

24、ifies the lowest level in any bill of material at which a particular component appears. net requirements for a given component are not calculated until all the gross requirements have been calculated down to that level. low-level codes are normally calculated and maintained automatically by the comp

25、uter software.a production area consisting of one or more machines that can be scheduling.considered as one unit for capacity requirements planning and detailed the amount of time, in hours, that a machine is actually running. machine hours, rather than labor hours, may be used for planning capacity

26、 for scheduling, and for allocating costs.the accumulation by workstation, machine, or machine group of the hours generated from the scheduling of operations for released orders by time period. machine loading differs from capacity requirements planning in that it does not use the planned orders fro

27、m mrp but operates solely from released orders. it may be of limited value because of its limited visibility of resources.a document, group of documents, or schedule conveying authority for the job order, manufacturing authorization, production order, production manufacture of specified parts or pro

28、ducts in specified quantities. a technique that schedules materials before processors . this technique facilitates the efficient use of materials. mds mrp systems use material-dominated scheduling logic.a type of order point replenishment system where the min is the order point, and the max is the o

29、rder up to inventory level. the order quantity is variable and is the result of the max minus available and on-order inventory. an order is recommended when the sum of the available and on-order inventory is at or below the min.a procedure used in some process industries for building process train s

30、chedules that start at an initial stage and work toward the terminal process stages. this procedure is effective for scheduling where several bottleneck stages may exist. detailed scheduling is done at each bottleneck stage.a technique for short-term planning of actual jobs to be run in each work ce

31、nter based upon capacity and priorities. the result is a set of projected completion times for the operations and simulated queue levels for facilities. a set of procedures for determining the lot size and other parameters related to an order. a lot-sizing technique under which the lot size is equal

32、 to the net requirements for a given number of periods, e.g. weeks into the future. the number of periods to order is variable, each order size equalizing the holding costs and the ordering costs for the interval.an inventory record keeping system where each transaction in and out is recorded and a

33、new balance is computed.a bill-of-material coding and structuring technique used primarily for is set to zero and the order quantity to lot-for-lot. a phantom bill of transient subassemblies. for the transient item, lead time material represents an item that is physically built, but rarely stocked,

34、before being used in the next step or level of manufacturing. this permits mrp logic to drive requirements straight through the phantom item to its components, but the mrp system usually retains its ability to net against any occasional inventories of the item. this technique also facilitates the us

35、e of common bills of material for engineering and manufacturing. the standard hours of work required by the planned production orders. a generalized method for planning equipment usage and material requirements that uses the process structure to guide scheduling calculations. it is used in flow envi

36、ronments common in process industries.production that adds value by mixing, separating, forming, and/or performing chemical reactions. it may be done in either batch or continuous mode. a technique that schedules equipment before materials. this technique facilitates scheduling equipment in economic

37、 run lengths and the use of low-cost production sequences. this scheduling method is used in some process -industries. equipment that performs a basic manufacturing step, such as mixing or packaging, is are combined into process trains. inventories decouple the scheduling of called a process unit. p

38、rocess units are combined into stages, and stages sequential stages within a process train.in the theory of constraints: the maximum of the output capabilities of a resource or the market demand for that output capacity.for a given time period. in the theory of constraints: a given amount of extra c

39、apacity at nonconstraints above the system constraints capacity, used to protect against statistical fluctuation. protective capacity provides nonconstraints with the ability to catch up to protect throughput and due date performance. a price reduction allowance determined by the quantity or value o

40、f a purchase.the amount of time a job waits at a work center before setup or work is performed on the job. queue time is one element of total manufacturing lead time. increases in queue time result in direct increases to manufacturing lead time and work-in-process inventories.the process of changing

41、 order or operation due dates, usually as a result of their being out of phase with when they are needed. reprocessing to salvage a defective item or part.in the theory of constraints: the planned amount by which the available capacity exceeds current productive capacity. this capacity provides prot

42、ection from planned activities, such as resource contention, and preventive maintenance and unplanned activities, such as resource breakdown, poor quality, rework, or lateness. safety capacity plus productive capacity plus excess capacity is equal to 100% of capacity. fluctuations in lead time so th

43、at an order can be completed before its an element of time added to normal lead time to protect against will plan both order release and order completion for earlier dates than real need date. when used, the mrp system, in offsetting for lead time, it would otherwise. the standard hours of work requ

44、ired by scheduled receipts, i.e., open production orders.material outside of specifications and possessing characteristics that make rework impractical.products that have been stored uncompleted awaiting final operations that adapt them to different uses or customer specifications. the time required

45、 for a specific machine, resource, work center, process, or line to convert from the production of the last good piece of item a to the first good piece of item b. reductions of actual quantities of items in stock, in process, or in transit. the loss may be caused by scrap, theft, deterioration, eva

46、poration, etc.in a min-max inventory system, the equivalent of the maximum. the target inventory is equal to the order point plus a variable order quantity. it is often called an order-up-to inventory level and is used in a periodic review system. the maximum output capability, allowing no adjustmen

47、ts for preventive maintenance, unplanned downtime, shutdown, etc.the amount of good or acceptable material available after the completion of a process. usually computed as the final amount divided by the initial amount converted to a decimal or percentage. in manufacturing planning and control syste

48、ms, yield is usually related to specific routing steps or to the parent item to determine how many units should be scheduled to produce a specific number of finished goods. for example, if 50 units of a product are required by a customer and a yield of 70% is expected then 72 units should be started

49、 in the manufacturing process. a management philosophy developed by dr. eliyahu m. goldratt that can be viewed as three separate but interrelated areas-logistics, performance measurement, and logical thinking. logistics include drum-buffer-rope scheduling, buffer management, and vat analysis. perfor

50、mance measurement includes throughput, inventory and operating expense, and the five focusing steps. thinking process tools are important in identifying the root problem, identifying and expanding win-win solutions and developing implementation plans. 附录b约束理论对于当前或潜在的问题，系统输出的需要什么或采取什么行为的指示。例如，在mrp系统里

51、，动作信息包括下达订单、建议提前日期、建议推迟日期、取消。在约束管理中，增加非约束资源的部件或产品以支持系统约束。结果是出现过多的在制品库存或完工品库存，或者这两种情况都有。相比之下，“利用率”这个词用来描述非约束资源的利用同步支持约束需要的情况。对已分配到指定订单但是还未从仓库下达到生产车间的物料数量的分类。（1）未兑现的仓库申请；（2）分配供应不足的物料的过程。备选的工艺路线，但是能生产出同样的产品。替代工艺路线可以在计算机中维护或被手工离线。但是计算机软件必须能够接受指定工作的替代工艺路线。工人或机器可用的工作时间的百分比。公式为可用率 (计划时间 停工时间)*100% / 计划时间在财

52、务上设定的产出的量/种类或制造管理费用/负荷吸收率。在toc中，所有的派遣工作都进入一个缓冲区。通过派遣这些物料进入缓冲区，系统能帮助你避免约束产生的空闲和错过客户的交期。另外，在缓冲区能够发现丢失物料的原因，有利于改善生产活动。生产过程中剩下的或附带产生的物料或价值。副产品与主产品的比率通常是可预知的。副产品可以被回收、出卖、作其他用途。系统或资源在一个特定时间里输出的能力。测量生产输出并将其与能力计划比较的过程，以决定它们的差异是否超过了预设的限制，如果超过了限制，需要检查计划、采取正确的行为。每处单品的库存点自行做库存决策。在制造的实体之间或分销网络之间保留的库存，用于建立流程与流程之间

53、或实体与实体之间的独立性。目的是分割物料供应率与物料使用率之间的联系。在产品结构或分销网络中库存的位置点，以此创建流程与流程之间或实体与实体之间的独立性。选择分离点是战略决策，能决定客户的提前期和库存投资。用于生产单个物料或一定数量的相似物料的工作中心。设备是专用的，可能是指定的设备或是用于制造混合部件的通用设备组。在toc中，是一个管理资源、最大化输出的总的流程。鼓点是系统约束设置的生产率或步调。缓冲器正对不确定性建立保护机制，这样，系统才能最大化输出。绳子是从约束到闸道操作的沟通流程，能检查或限制下达到系统的物料以支持约束。客户指定对产品的规格，需要单独的流程涉及、客户化程度高、或者就是新

54、产品。每个客户订单都需要单独设置物料号、物料清单、工艺路线。在一个非约束资源环境里，输出的能力超过约束要求的生产能力和保护能力。用于核算的库存评估方法。核算假设最早的库存要先用掉。但是，这与实际的指定物料的物理移动没有必然的联系。（1）制造系统对外部和内部的变化在范围和时间上的快速反应的能力。6种柔性类别：种类柔性、设计换模柔性、修改柔性、量柔性、重设工艺路线柔性、物料柔性。另外，柔性还考虑到产品柔性。在应对各种不确定性时柔性很有用。（2）在增加或降低产品量的过程中，供应链减轻、抵消需求预测的变化、连续供应的变化、周期加上提前期的不确定性、运输时间加上报关时间的不确定性的风险的能力。流程是从第

55、一阶段开始排，按顺序排到最后一阶段。在一个特别的工艺路线顺序里，执行第一道工序的工作中心。通常是链接的资源的系统不用的能力。根据toc，闲置能力由保护能力和过剩能力组成。核算库存价值。可用永续库存或周期库存记录库存或评估库存价值。永续库存记录要定期更新或实时更新。周期库存是在固定的时间间隔里进行计算，如：每2周或每月。库存评估法有后进先出、先进先出、平均成本。用于保护工序的输出、或由于交付延迟、质量问题、数量交付错误等导致的计划排期。在库存各个阶段的钱。公司对于库存管理的目标和方法的一个描述。协调相关物料的批量和订单下达，把他们视为一个产品族。目的是因为订单准备、发运、数量折扣等因素能实现更低的成本。这个术语应用于联合订单品族和组合部件排期。待添加的隐藏文字内容3核算用的库存评估方法。考虑成本因素，核算假定最后接收的最先使用或售出。但是它和指定物料的实际物理移动没有必然的联系。决定批量大小的流程或技术。将1个批次分为2个或更多的子批次，同时将每个子批次在同一个设备上加工成独立的批次。这样做通常能压缩提前期、或迅速完成小数量的任务。物料清单最低级的号码，在这一级，列出组件。直到毛需求展开到这一级，才能计算净需求。低位码通常由计算机软件自动计算和维护。由一个或更