Theory of Constraints Handbook - James Cox Iii [759]
18Actually, this perception is wrong because the processing time is a negligible part of the lead time and the main part dictating the delivery time is the required waiting for the resource with the least capacity.
19The APICS Dictionary (Blackstone, 2008, 56) defines funnel experiment— “An experiment that demonstrates the effects of tampering. Marbles are dropped through a funnel in an attempt to hit a flat-surfaced target below. The experiment shows that adjusting a stable process to compensate for an undesirable result or an extraordinarily good result will produce output that is worse than if the process had been left alone. “(© APICS 2008, used by permission, all rights reserved.)
20A detailed discussion on how to deal with sequence-dependent-setups can be found in Schragenheim, Dettmer, and Patterson (2009, 79–86).
21When orders are late we sometimes call them “black.” The author believes that black is not part of the priority system and not necessarily a black order has higher priority over red orders.
22For a more detailed discussion, see Schragenheim et al. (2009, 74–79).
23The TOCICO Dictionary (Sullivan et al., 2007, 27) defines “I-plant—A production environment where materials generally flow through a direct sequence of operations. The logical flow of materials resembles the letter I in the sense that is, there are few divergent points, as in a V-plant, and few convergent points, as in an A-plant. Examples: Transfer or assembly lines such as used to assemble lawn mowers.” (© TOCICO 2007, used by permission, all rights reserved.)
1For those interested, marketing is covered in Chapter 22 and sales management is covered in Chapter 23 of this Handbook.
2For those unfamiliar with MRP see, for example, Arnold, Chapman, and Clive (2008).
3In the MRP literature, this condition is called nervousness, which the APICS Dictionary (Blackstone, 2008, 86) defines as “(t)he characteristic in an MRP system when minor changes in higher level (e.g., level 0 or 1) records or the master production schedule cause significant timing or quantity changes in lower level (e.g., level 5 or 6) schedules and orders.” (© APICS 2008, used by permission, all rights reserved.)
4The difference we mean here between sales and consumption is when certain items “vanish,” either because they were scrapped, stolen, or lost. The default action here is still to replenish them.
5The shipping buffer is a time buffer used in DBR to protect the due date of an order. In MTA, we need to protect the availability, so it has to be a different type of a buffer but for the same purpose of protecting the satisfaction of the clients. Thus, the quotation marks mean that it is not the same but the objective is similar.
6Replenishment time in TOC differs considerably from traditional inventory management. In both the min-max and reorder point/economic order quantity inventory system, items are sold over some time period and only when the minimum point or the reorder point is reached and an order is placed. Replenishment time starts when an order is placed for an item and ends when the item is restocked and available for sale. Note in the TOC, replenishment is triggered by time (daily or weekly maybe) and in traditional methods triggered by an inventory level falling to or below some reorder level.
7Note that the term “reliable replenishment time” is different than the term “replenishment time,” which is the average.
8The author defines the abstract term of “protective capacity” as the level where the lack of immediate available capacity starts to cause real damage.
9The regular planned load is the one for daily use. A full planned load will be defined later as consisting of all required replenishments including those that were not released.
10It could be the case where the minimum batch is aimed to keep another resource, with long setups but fast processing pace, from becoming a bottleneck. Therefore, the minimum batch is a must,