Chapter 15 Operations Mgmt 9121

Chapter 15 JIT and Lean Operations True/False 1. JIT refers to a production system in which input resources arrive for processing just as the preceding batch is completed. Answer: True Page: 679 Difficulty: Easy 2. A functioning MRP system is required prior to using JIT as the planning and control system. Answer: False Page: 679 Difficulty: Easy 3. In a JIT environment, anything not essential to the product or process is viewed as waste. Answer: True Page: 680 Difficulty: Easy 4. The ultimate goal of JIT is a system that achieves smooth, rapid flow of materials through the system. Answer: True Page: 682 Difficulty: Easy 5. Although inventories are maintained, the goal of JIT is to minimize safety stock. Answer: False Page: 682 Difficulty: Easy 6. The use of JIT results in a production system unable to easily handle changes of output or product mix.. Answer: False Page: 682 Difficulty: Easy 7. In the JIT philosophy, producing more than two order quantities represents waste. Answer: False Page: 680 Difficulty: Medium 8. The four building blocks of JIT are: product design, process design, personnel/organizational elements, and manufacturing planning and control. Answer: True Page: 684 Difficulty: Easy Learning Objective: CA 9. Fast and simple are two common threads that run through the four building blocks of JIT. Answer: True Page: 684 Difficulty: Easy 10. Big JIT primarily focuses on inventory while little JIT focuses on cost. Answer: False Page: 683 Difficulty: Medium

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11. While big JIT refers to attempts to schedule materials used in all production activities, little JIT has a narrow focus on scrap reduction. Answer: False Page: 683 Difficulty: Medium 12. Quality and highly capable production systems are requirements for successful JIT implementation. Answer: True Page: 702 Difficulty: Medium 13. The small lot-sizing policy works well in a situation where both holding costs and setup costs are high. Answer: False Page: 685 Difficulty: Hard 14. The use of small lot sizes in JIT is in conflict with the EOQ approach since setup costs tend to be significantly higher than holding costs. Answer: False Page: 685 Difficulty: Medium 15. A basic requirement for operating with low inventories in JIT systems is that major system problems must already have been solved and new problems will be solved as they appear. Answer: True Page: 684 Difficulty: Hard 16. A benefit of small lot sizes in JIT systems is each product is produced less frequently. Answer: False Page: 685 Difficulty: Easy 17. In the JIT philosophy, the larger the lot size, the easier it is to schedule. Answer: False Page: 685 Difficulty: Easy 18. Setup time and its associated cost can often be reduced by the use of group technology. Answer: True Page: 685 Difficulty: Medium 19. JIT systems often use layouts that are based on group technology product requirements. Answer: True Page: 685 Difficulty: Medium 20. The goal of JIT is to produce output using fewer resources than traditional planning systems. Answer: True Page: 682 Difficulty: Easy Learning Objective: Ref 21. “Autonomation” indicates that the firm is attempting to reduce its dependence on automated equipment. Answer: False Page: 687 Difficulty: Easy

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22. “Preventive maintenance” is additional maintenance done immediately after a breakdown has occurred to help prevent any further breakdowns. Answer: False Page: 701 Difficulty: Easy 23. In the JIT approach, inventories are reduced gradually, instead of eliminating inventories as rapidly as possible. Answer: True Page: 682 Difficulty: Easy 24. One problem with JIT is that it can lead to much frustration and disappointment of people on the shop floor due to the need for continuously monitoring and expediting resource availability. Answer: True Page: 691 Difficulty: Medium 25. A real advantage to JIT is the reduction of co-ordination effort required. Answer: False Page: 617 Difficulty: Easy 26. The JIT philosophy recognizes that some work in process inventories are a necessary investment to allow for smooth work-flow. Answer: False Page: 680 Difficulty: Medium Learning Objective: Ref 27. Preventive maintenance will eliminate the need to carry supplies of spare parts. Answer: False Page: 701 Difficulty: Hard 28. A fundamental tenet of the JIT philosophy is that workers are paid based on seniority. Answer: False Page: 691 Difficulty: Easy 29. A responsibility of the JIT cross-trained worker is to check the quality of the work of others. Answer: True Page: 691 Difficulty: Medium 30. In JIT, when work is completed at one work center, it is important to immediately move the completed work to the next work center to minimize idle time.. Answer: False Page: 680 Difficulty: Medium 31. In a “pull system,” a quantity of inventory in front of a workstation indicates problems at that workstation. Answer: True Page: 680 Difficulty: Hard 32. Limited WIP lowers inventory carrying costs but reduces flexibility. Answer: False Page: 680 Difficulty: Medium Learning Objective: CA

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33. Engineering changes can be very disruptive to smooth operations and should not be made in the six month period following introduction of a new product. Answer: False Page: 684 Difficulty: Medium 34. Kanban is the Japanese term for autonomation. Answer: False Page: 695 Difficulty: Medium 35. Increased setup times equal increased work in process inventories. Answer: True Page: 679 Difficulty: Medium 36. Kanban focuses on specific part numbers; CONWIP does not. Answer: True Page: 695 Difficulty: Hard 37. JIT systems typically require that suppliers be able to provide large lots at periodic intervals. Answer: False Page: 685 Difficulty: Medium 38. JIT purchasing requires frequent contract bidding by multiple sources to ensure the buyer of competitive prices. Answer: False Page: 699 Difficulty: Medium 39. One way of reducing the number of suppliers to the organization is to limit s to only one or two tiers of suppliers. Answer: False Page: 699 Difficulty: Easy 40. One major difference between the use of kanban and MRP II in scheduling the products to be built is that kanban is primarily a manual system while MRP II uses computers. Answer: True Page: 695 Difficulty: Hard 41. A benefit of JIT is the flexibility to respond quickly to changing customer requirements. Answer: True Page: 685 Difficulty: Easy 42. A benefit of JIT systems is that lead times are increased allowing more time for processing. Answer: False Page: 680 Difficulty: Medium 43. A successful conversion to a JIT system requires that every vendor use JIT approaches prior to the organization's implementation of JIT. Answer: False Page: 700 Difficulty: Medium 44. The single-minute exchange of die is a system for reducing defective product.

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Answer: False

Page: 686

Difficulty: Hard

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45. In a balanced system cycle time is equal to Takt time. Answer: True Page: 687 Difficulty: Hard 46. It is important to lower the water (inventory) completely to expose all the rocks (problems). Answer: False Page: 688 Difficulty: Medium 47. Successful JIT implementation requires much more than slogans and idealistic goals such as zero inventories and zero defects. Answer: True Page: 700 Difficulty: Easy 48. JIT concepts include large lots to take advantage of the economies of scale. Answer: False Page: 685 Difficulty: Easy 49. JIT II is a philosophy that involves empowering suppliers to assume some of the responsibilities ordinarily done by a company's own buyers. Answer: True Page: 699 Difficulty: Medium Multiple Choice 50. JIT in its conceptual sense: A) is a lean production system B) has no idle items waiting to be processed C) has no idle workers D) has no idle workstations waiting to process work E) all of the above Answer: E Page: 679 Difficulty: Easy 51. JIT philosophy suggests that workers are … A) Assets B) Liabilities C) Interchangeable D) Replaceable E) To be phased out Answer: A Page: 679 Difficulty: Medium 52. The ultimate goal of JIT is to have: A) no in-process inventories B) cross-trained workers capable of handling every process C) a smooth, rapid flow of materials through the system D) no setup times E) all of the above Answer: C Page: 682 Difficulty: Medium Learning Objective: AS

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53. Which one of the following is not one of the building blocks that is the foundation of JIT? A) product design B) process design C) personnel/organizational elements D) manufacturing planning and control E) kanban Answer: E Page: 684 Difficulty: Medium 54. Building up an inventory of standard parts or modules instead of immediately producing the finished end items is the essence of: A) delayed differentiation B) kanban C) autonomation D) andon E) matrix management Answer: A Page: 684 Difficulty: Medium 55. Which of the following would you not expect to see in JIT? A) a flexible system B) minimum inventory C) little waste D) reduced setup times E) a significant number of daily schedule changes Answer: E Page: 680 Difficulty: Medium 56. The comprehensive approach used in JIT systems to deal with quality includes: A) deg quality into products and processes B) insisting vendors provide high quality materials C) making workers responsible for producing high quality D) A, B and C E) 100% inspection of raw materials, work-in-process and finished goods Answer: D Page: 691 Difficulty: Easy 57. Which of the following is not a benefit of small lot sizes in JIT systems? A) In-process inventory is considerably less. B) Each product is produced less frequently. C) Carrying costs are reduced. D) There is less clutter in the workplace. E) Inspection and rework costs are less. Answer: B Page: 685 Difficulty: Medium

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58. In the JIT philosophy, the ideal lot size is: A) the economic order quantity B) the economic run size C) one unit D) the capacity of the standard container E) N=(DT(1+X))/C Answer: C Page: 685 Difficulty: Easy 59. Which of the following does not contribute to reduced setup time and cost? A) standardized setup tools B) standardized setup equipment C) custom setup procedures for each product D) use of multipurpose equipment or attachments E) use of group technology Answer: C Page: 685 Difficulty: Medium 60. A conveyance __________ signals parts movement. A) JIT B) Routing C) Bar code D) Kanban E) Kazian Answer: D Page: 695 Difficulty: Medium 61. The term that refers to the automatic detection of defects is: A) kaizen B) kanban C) autonomation D) automation E) 100% inspection Answer: C Page: 687 Difficulty: Easy 62. A basic requirement for operating with the low inventories present in JIT systems is: A) Inventory space must be increased. B) Inventory investment must be increased. C) Major problems must be identified. D) Major problems must have been solved. E) Inventories must be reduced rapidly. Answer: D Page: 686 Difficulty: Hard

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63. Which of the following is not characteristic of preventive maintenance in JIT systems? A) maintaining equipment in good operating condition B) replacing parts when they are worn but before they fail C) workers maintaining their own equipment D) eliminating supplies of spare parts to reduce capital investment E) perceiving breakdowns as an opportunity for improvement Answer: D Page: 701 Difficulty: Hard 64. The Five S’s don’t include … A) Sort B) Straighten C) Sanitize D) Sweep E) Standardize Answer: C Page: 701 Difficulty: Hard 65. The Kaizen Philosophy applies to … A) Employee development B) Safety stock C) Waste D) Supply Chain Management E) MRP III Answer: C Page: 681 Difficulty: Medium 66. A kanban card is used to signal that: A) work is needed at the work center B) work is ready to be moved to the next station C) a worker has run out of parts needed for further processing D) a machine has broken down and needs immediate attention E) a machine is ready for preventive maintenance Answer: A Page: 695 Difficulty: Hard Learning Objective: AS 67. With regard to suppliers, JIT systems typically require: A) delivery of large lots at regular intervals B) buyer inspection of goods and materials C) multiple sources from which to purchase D) long-term relationships and commitments E) the lowest price possible Answer: D Page: 699 Difficulty: Medium

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68. Which of the following is characteristic of the JIT philosophy? A) Inventories are an asset. B) Lot sizes are optimized by formula. C) Vendors are co-workers, essentially other departments of our organization. D) Queues are a necessary investment. E) all of the above Answer: C Page: 699 Difficulty: Medium 69. The activities controlled in the same way by kanban and MRP II is the determination of: A) rates of output B) products to be built C) materials required D) capacity required E) information Answer: B Page: 695 Difficulty: Hard 70. Process design ing JIT doesn’t include … A) Production flexibility. B) Duplicate facilities. C) Setup time reduction. D) Minimal inventory storage. E) Small lot sizes Answer: B Page: 684 Difficulty: Hard 71. Allowing suppliers to manage the restocking of their products in our inventories is part of: A) Vertical Integration B) Kanban C) JIT II D) Backflushing E) Enabling Answer: C Page: 702 Difficulty: Hard 72. A successful conversion to a JIT system requires that the conversion: A) be done as quickly as possible B) begin at the start of the process and work forward C) convert vendors to JIT as one of the last steps D) reduce setup times as one of the last steps E) all of the above Answer: C Page: 700 Difficulty: Medium

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73. A potential obstacle to conversion to a JIT system is: A) lack of management commitment B) lack of worker cooperation C) supplier resistance D) all of the above E) insufficient space to store the increased inventories Answer: D Page: 700 Difficulty: Easy 74. A system of lights used at each workstation to signal problems or slowdowns is: A) command and control center B) automation C) andon D) pull system E) kanban Answer: C Page: 692 Difficulty: Easy 75. Which of the following contributes to the competitive advantage enjoyed by firms using JIT/lean production? A) Backup employees to cover for absenteeism B) 100% inspection to remove defects C) Dedicated equipment to reduce unit costs D) Safety stocks to prevent stock-outs E) Greater flexibility to cope with change Answer: E Page: 680 Difficulty: Medium 76. An operations strategy toward the JIT philosophy of production should recognize that JIT: A) is most suited for non-repetitive manufacturing B) cannot be implemented sequentially C) requires a wholesale commitment from the outset D) may provide a competitive advantage E) all of the above Answer: D Page: 679 Difficulty: Hard 77. With regard to suppliers, JIT systems typically involve: A) delivery of large lots on short notice B) the highest quality at the lowest price C) long-term relationships D) multiple suppliers to assure continuous availability E) dedicated staging areas for material Answer: C Page: 699 Difficulty: Medium

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78. A common objective of both MRP and JIT is to: A) smooth production B) minimize inventory C) obtain high quality D) reduce overhead E) eliminate inventory Answer: B Page: 680 Difficulty: Medium 79. The ultimate objective in a JIT system is: A) low to moderate levels of inventory B) high quality, zero defects C) minimal waste (less than 6%) D) balanced and rapid flow E) all of the above Answer: D Page: 682 Difficulty: Medium Essay 80. The All Seasonings Company uses 3,200 glass jars at one of its jar-filling workstations each eight hours of production. The cycle time for a standard container, which holds 90 jars, averages 45 minutes. If management uses an efficiency factor of twenty percent, how many containers should be used? Difficulty: Medium Answer: N=? D = 3200/8 = 400 jars per hour T = 45/60 = .75 hour X = .20 C = 90 jars

N=

DT(1 + X) ( 400)(.75)(1.20) 360 = = = 4 containers C 90 90

81. The Four Star Publishing Company uses sixty reams of paper each hour at one of its high speed printing stations. The cycle time for a standard container, which holds 15 reams of paper, averages forty minutes. If management has decided to use three containers, what efficiency factor was applied? Difficulty: Medium Answer: X=? N = 3 containers D = 60 reams per hour T = 40/60 = 2/3 hour C = 15 reams

X=

NC (3)(15) 45 −1 = −1 = − 1 = 1.125 − 1 = .125 or 12.5% DT (60)( 2 / 3) 40

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82. A production system uses kanban cards to control production and movement of parts. One work center uses an average of 40 pieces per hour of a certain part. Standard containers hold 10 parts. The cycle time for parts containers is about 36 minutes. Management has assigned an efficiency factor of .20 to this work center. How many containers should be used to this operation? Difficulty: Medium Answer: N=? D = 40/hour

T = .6 hours N =

DT(1 + X) 40(.6)1.2 = = 2.88 or 3 containers C 10

X = .20 C = 10 83. A production cell uses 240 pounds of plastic resin each 8-hour day. Resin is transported in drums that hold 100 pounds each. The material is obtained from a nearby supplier, and has a 12-hour cycle time. An efficiency factor of .15 has been assigned to this cell. What is the optimum number of containers to this operation? Difficulty: Medium Answer: N=? D = 240/8 = 30 pounds/hour T = 12 hours

X = .15

N=

DT(1 + X) 30(12)1.15 = = 4.14 or 5 containers C 100

C = 100 pounds

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