Test-Bank-for-Heizer-Operations-Management-9e

76.Which one of the following does not exemplify JIT used for competitive advantage?

a.Acme Foods decides to decrease the number of its suppliers to just a few.

b.Ajax, Inc. is proud to announce that incoming goods are delivered directly to the point of use.

c.Ardoyne Builders has a scheduled preventive maintenance program.

d.Cheramie Trucking trains workers to specialize and become very efficient in one job.

e.Cajun Contractors has reduced the amount of space for inventory.

d (Multiple sections, moderate)

77.Which one of the following is not a requirement of JIT systems?

a.quality deliveries on time

b.low setup time

c.training support

d.strong job specialization

e.employee empowerment

d (Multiple sections, moderate)

78.Great Lakes Barge and Baggage Company makes, among other things, battery-operated bilge pumps. Which of the following activities is not part of JIT? They

a.communicate their schedules to suppliers

b.produce in long production runs to reduce the impact of setup costs

c.use a pull system to move inventory

d.continuously work on reducing setup time

e.produce in small lots

b (Multiple sections, moderate)

79.Which one of the following is an example of JIT being used for competitive advantage?

a.Jones Company has decreased the number of job classifications to just a few.

b.Lafourche Metals increases the number of its suppliers to be less dependent on just a few.

c.Houma Fabricators is proud to announce that incoming goods are inspected.

d.Acme Company tells its maintenance department to intervene only if a machine breaks down.

e.Caro Specialty Metals, Inc. has built a new, huge warehouse to store inventory.

a (Multiple sections, moderate)

80.A manufacturer took the following actions to reduce inventory. Which of these is generally not accepted as a JIT action?

a.It used a pull system to move inventory.

b.It produced in ever smaller lots.

c.It required deliveries directly to the point of use.

d.It picked the supplier that offered the lowest price based on quantity discounts.

e.It worked to reduce the company's in-transit inventory.

d (Multiple sections, moderate)

81.Which of the following is not one of the Seven Wastes?

a.overproduction

b.transportation

c.assignment

d.defective product

e.motion

c (Just-in-time, the Toyota production system, and lean operations; easy)

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82.Concerning relationships with suppliers, which of the following combinations is critical to the success of JIT?

a.close relationships with trust

b.close relationships with skepticism

c.distant relationships with trust

d.distant relationships with skepticism

e.none of the above

a(Just-in-time (JIT), easy)

83.Which of the following statements regarding JIT in services is true?

a.Restaurants do not use JIT layouts because they interfere with creation of a good servicescape.

b.Excess customer demand in services such as air travel is met by dipping into safety stocks.

c.All of the JIT techniques for dealing with suppliers, layout, inventory, and scheduling are used in services.

d.Scheduling is not relevant to effective use of JIT in services.

e.All of the above are false.

c (Lean operations in services, moderate)

FILL-IN-THE-BLANK

84.____________ is the minimum inventory necessary to keep a perfect system running.

Just-in-time inventory (Just-in-time, the Toyota production system, and lean operations; moderate)

85.____________ is the Japanese word for card that has come to mean "signal."

Kanban (JIT scheduling, moderate) {AACSB: Communication}

86.When suppliers are encouraged to locate near manufacturing plants, the goal of the JIT partnership is to reduce ___________________ inventory.

in-transit (Just-in-time (JIT), easy)

87.____________ is any deviation from the optimum process that delivers perfect product on time, every time.

Variability (Just-in-time, the Toyota production system, and lean operations; moderate)

88.A(n) _________________ is a JIT concept that results in material being produced only when requested and moved to where it is needed just as it is needed.

pull system (Just-in-time, the Toyota production system, and lean operations; moderate)

89.The ___________________ is the time between the arrival of raw materials and the shipping of finished products.

manufacturing cycle time (Just-in-time, the Toyota production system, and lean operations; moderate)

90.___________________ allows manufacturing work cells and offices to be easily rearranged.

Layout flexibility (JIT layout, easy)

91.The main focus of JIT efforts to reduce investment in inventory requires _____________. small lot sizes or reduction of lot size (JIT inventory, easy)

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92.___________________ gets suppliers to accept responsibility for satisfying end customer needs.

Educating suppliers (Lean operations, easy)

93._______________ involves scheduling products so that each day's production meets the demand for that day.

Level scheduling (JIT scheduling, moderate)

94.TPS stands for ___________________.

Toyota Production System (Just-in-time, the Toyota production system, and lean operations; easy)

95.The 5S term _______________ includes analysis to improve workflow and reduce wasted motion. simplify/straighten or simplify (Just-in-time, the Toyota production system, and lean operations; easy)

96.Handling material more than once is an example of the waste called ___________________. transportation (Just-in-time, the Toyota production system, and lean operations; easy)

SHORT ANSWERS

97.What does TPS stand for?

Toyota Production System (Just-in-time, the Toyota production system, and lean operations; easy)

98.Define variability within the context of JIT.

Variability is any deviation from the optimum process that delivers perfect products on time every time. (Just-in-time, the Toyota production system, and lean operations; moderate)

99.Differentiate between a push and a pull system.

A push system pushes material into downstream workstations regardless of the resources available. A pull system uses signals to request delivery from upstream stations to the station that has production facilities available. In a pull system, materials or parts are pulled where they are needed when they are needed. (Just-in-time, the Toyota production system, and lean operations; moderate)

100.Define manufacturing cycle time in the context of JIT systems.

Manufacturing cycle time is the time between receipt of raw materials and shipment of the finished product. (Just-in-time, the Toyota production system, and lean operations; moderate)

101.Identify sources of variability.

1.Incomplete or inaccurate drawings or specifications

2.Late or non-comforming units

3.Unknown customer demands

(Just-in-time, the Toyota production system, and lean operations; moderate)

102.What three things does the Toyota Production System (TPS) emphasize?

Focus on continuous improvement, respect for people, and standard work practices. (Just-in- time, the Toyota production system, and lean operations; moderate)

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103.What are the goals of JIT partnerships?

1.Removal of unnecessary activities, such as receiving, incoming inspection, and paperwork related to bidding, invoicing, and payment.

2.Removal of in-plant inventory by delivery in small lots directly to the using department as needed.

3.Removal of in-transit inventory by encouraging suppliers to locate nearby and provide frequent small shipments.

4.Obtain improved quality and reliability through long-term commitments, communication, and cooperation.

(Just-in-time (JIT), moderate)

104.Compare and contrast throughput with manufacturing cycle time.

Throughput is a measure (in units or time) that it takes to move an order from receipt to delivery. Each minute that products remain on the books, costs accumulate and competitive advantage is lost. On the other hand, the time that an order is actually in the shop is called manufacturing cycle time. This is the time between the arrival of raw materials and the shipping of finished product. Driving down manufacturing cycle time can make a major improvement in throughput. (Just-in-time, the Toyota production system, and lean operations; moderate)

105.What are the five reasons given by suppliers for their reluctance to enter into JIT systems? Elaborate on one of these, of your choosing.

The five reasons are desire for diversification, poor customer scheduling, engineering changes, quality assurance, and small lot sizes. (Just-in-time (JIT), moderate)

106.Identify the layout tactics appropriate for a JIT environment.

Layout tactics for a JIT environment include build work cells for families of products, include a large number of operations in a small area, minimize distance, design little space for inventory, improve employee communication, use poka-yoke devices, build flexible or movable equipment, and cross-train workers to add flexibility. (JIT layout, moderate)

107.Identify the inventory tactics appropriate for a JIT environment.

Inventory tactics for a JIT environment include a pull system to move inventory, ever smaller lots, just-in-time deliveries from suppliers, deliveries directly to point of use, performance to schedule, setup reduction, and group technology. (JIT inventory, moderate)

108.What is a kanban?

Kanban is the Japanese word for card that has come to mean "signal." A kanban system moves parts through production via a "pull" from a signal. (JIT scheduling, easy) {AACSB: Communication}

109.Describe level schedules. What purpose do they serve?

Level schedules act on frequent small batches rather than a few large batches; the small batches are always changing. The practice matches one day's demand to one day's work. (JIT scheduling, moderate)

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110.Identify JIT scheduling tactics.

JIT scheduling tactics include communicate schedules to suppliers; make level schedules; freeze part of the schedule; perform to schedule; seek one-piece-make and one-piece-move; eliminate waste; produce in small lots; use kanbans; and make each operation produce a perfect part. (JIT scheduling, moderate)

111.Identify some of the signals that kanban systems use.

Kanban systems use a wide variety of signals. These include cards, lights, an empty position, an empty tote tray, a rag over a rack adjacent to a storage area, or a post that indicates how high the inventory should be in the storage area. (JIT scheduling, easy) {AACSB:

Communication}

112.Explain how JIT works in services. After all, how does "small lot size" and "reduce setup cost" make sense in services? Supply examples to support your work.

In services, JIT works more on scheduling than on inventory, but is otherwise quite applicable. Furthermore, many services, such as restaurants, have significant inventories to deal with. (JIT in services, moderate)

113.How are lean operations and the Toyota Production System (TPS) alike? How are they different?

Lean operations and TPS are basically synonymous, and the two terms are often used interchangeably. The approach we call lean operations was begun by two employees at Toyota. Lean operations places more emphasis on understanding the customer; TPS places more emphasis on employee empowerment. (Lean operations, easy)

114.What are the 5S's? Why does the list of the 5S's sometimes have seven elements?

The five terms are sort/segregate, simplify/straighten, shine/sweep, standardize, and sustain/self discipline. American practice often adds safety and support/maintenance. (Just- in-time, the Toyota production system, and lean operations; moderate)

115.Identify Ohno's Seven Wastes. Which one of these deals most directly with distance reductions?

The seven are overproduction, queues, transportation, inventory, motion, overprocessing, and defective product. Transportation is the obvious choice, but motion may also be appropriate. (Just-in-time, the Toyota production system, and lean operations; moderate)

116.Identify JIT policies for and expectations of suppliers.

Few vendors; supportive supplier relationships; and quality deliveries on time, directly to work areas. (Just-in-time (JIT), easy)

PROBLEMS

117.Weekly usage of a product is 8 units. Since the plant operates 50 weeks per year, this leads to annual usage of 400 units. Setup cost is $40 and annualized carrying cost is $80. Weekly production of this product is 12 units. Lead time is four weeks, and safety stock is one week's production. What is optimal kanban size? What is the optimal number of kanbans?

35; 44/35→2 (JIT scheduling, moderate) {AACSB: Analytic Skills}

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118.You have read that in JIT and lean production the optimum lot size is one, with some exceptions for packaging and physical limitations. If a product currently has a lot size of 25, what must happen to setup time for the lot size to truly fall to one? Data for this problem are D=100 units, S=$75 based on setup time of 50 minutes at $1.50 per minute, and H=$40 per unit per year.

Students may try ever smaller values for S, and find S =$0.12 by trial and error. Or they may solve the economic production quantity model for S, which also yields $0.12. Or they may recognize that the reduction in Q by a factor of 25 requires a reduction in S by that factor squared; in this case $75 / (25*25) = 0.12. (JIT inventory, moderate) {AACSB: Analytic Skills}

119.Daily usage of a product is 10 in a facility that operates every day of the year. Setup cost is $68 and annualized carrying cost is $100. Daily production of this product is 20. Lead time is 14 days; safety stock is one day's production. What is the optimum kanban size, and number of kanbans?

100; 160/100→2 (JIT scheduling, moderate) {AACSB: Analytic Skills}

120.Daily usage of an assembly is 100 in a facility that operates 300 days of the year. Setup cost is $5 and annualized carrying cost is $160. Production of this assembly occurs at the rate of 400 per day when production of the assembly is underway. Lead time is 3 days; safety stock is 1/2 day's production. What is the optimum kanban size, and number of kanbans?

50; 500/50=10 (JIT scheduling, moderate) {AACSB: Analytic Skills}

121.Daily usage of a part is 20 in a facility that operates 250 days of the year. Setup cost is $20 and annualized carrying cost is $210. Production of this part occurs at the rate of 50 per day when production of the part is underway. Lead time is 1 day; safety stock is 1/2 day's production. What is the optimum kanban size, and number of kanbans?

40; 45/40→2 (JIT scheduling, moderate) {AACSB: Analytic Skills}

122.A certain product has been effectively managed in the past, according to its managers.

The previous technique used the economic production quantity model, and resulted in an optimum lot size of 100. For this product, setup time is directly proportional to setup cost, and setup time is currently 40 minutes per batch. How much must setup time decline in order for the lot size to fall to 50 units? 25 units? 10 units?

Complete data for the problem is not necessary. To cut the lot size in half, S must be cut to 25 percent of its pervious value, or from 40 minutes to 10 minutes. The reduction of lot size to 25 units requires another reduction by a factor of four, to 2.5 minutes. Reducing the lot size by a factor of ten requires the reduction in setup time by a factor of 100, the equivalent of 0.4 minutes. (JIT inventory, moderate) {AACSB: Analytic Skills}

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123.A repetitive manufacturing firm is planning on level material use. The following information has been collected. Currently, the firm operates 250 days per year.

a.What is the setup cost, based on the desired lot size? b. What is the setup time, based on $40 per hour setup labor?

(b) Setup time = 4.38 min

(JIT inventory, moderate) {AACSB: Analytic Skills}

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CHAPTER 17: MAINTENANCE AND RELIABILITY

TRUE/FALSE

1.Orlando Utilities Commission uses a computerized maintenance management program, and devotes significant dollar and labor resources to power plant maintenance, because the costs of unexpected failure are incredibly high.

True (Global company profile, easy) {AACSB: Use of IT}

2.Maintenance includes all activities involved in keeping a system's equipment in working order.

True (The strategic importance of maintenance and reliability, easy)

3.Reliability is the probability that a machine part or product will function properly for a specified time regardless of conditions.

False (The strategic importance of maintenance and reliability, easy)

4.The product failure rate is the percentage of failures among the total number of products tested.

True (Reliability, moderate)

5.The MTBF (mean time between failures) is calculated as the reciprocal of the number of failures during a period of time.

True (Reliability, moderate)

6.If the mean time between failures has been calculated to be 2,000 hours, then the number of unit failures per 2,000 hours must be one.

False (Reliability, moderate)

7.The reliability of a system in which each individual component must function in order for the entire system to function, and in which each component has its own unique reliability, independent of other components, is the product of the probabilities of each of those components.

True (Reliability, moderate)

8.Adding an additional part to a component or product ordinarily reduces reliability by introducing an additional source of failure.

True (Reliability, moderate)

9.A redundant part or component increases reliability because it is connected in parallel, not in series.

True (Reliability, moderate)

10.A redundant part decreases reliability if the reliability of the redundant part is lower than that of the part it is backing up.

False (Reliability, moderate)

11.Preventive maintenance is reactive.

False (Maintenance, moderate)

12.Preventive maintenance is nothing more than keeping the equipment and machinery running.

False (Maintenance, moderate)

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13.Preventive maintenance implies that we can determine when a system needs service or will need repair.

True (Maintenance, moderate)

14.Infant mortality refers to the high failure rate often encountered in the very early stages of the lifetime of a product.

True (Maintenance, moderate)

15.The failure distributions of products, machines, or processes that have "settled in," or gone beyond the infant mortality phase, often follow the normal distribution.

True (Maintenance, easy)

16.Recording the maintenance history of processes, machines, or equipment is important for preventive maintenance, but largely irrelevant for breakdown maintenance.

False (Maintenance, easy)

17.The "full cost view of maintenance" results in more firms choosing a policy of breakdown maintenance, when compared to the "traditional view of maintenance."

False (Maintenance, easy)

18.Failures are tolerable as long as their results are not catastrophic.

False (Maintenance, moderate)

19.Small standard deviations in the MTBF distribution of a machine tend to support a policy of breakdown maintenance for that machine.

False (Maintenance, moderate)

20.When identifying the optimal maintenance policy, the cost of inventory maintained to compensate for the downtime is a cost often ignored.

True (Maintenance, moderate)

21.An optimal maintenance policy strikes a balance between the costs of breakdown and preventive maintenance so that the total cost of maintenance is at a minimum.

True (Maintenance, moderate)

22.While breakdowns occur randomly, their frequency is somewhat predictable through such tools as the product failure rate, MTBF, and the breakdown costs model.

True (Maintenance, moderate)

23.The objective of maintenance and reliability is to maintain the capability of the system.

True (The strategic importance of maintenance and reliability, moderate)

24.TPM (total productive maintenance) is an application of TQM (total quality management) principles to the area of maintenance.

True (Total productive maintenance, moderate)

25.Simulation models and expert systems are useful tools for determining maintenance policies.

True (Techniques for enhancing maintenance, moderate) {AACSB: Use of IT}

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MULTIPLE CHOICE

26.Which of the following statements about maintenance at Orlando Utilities Commission is false?

a.There are at least two types of preventive maintenance, including an annual maintenance and a less frequent overhaul schedule.

b.Its preventive maintenance program has earned the company top rankings and its competitive advantage.

c.Each power-generating unit is taken off-line every three years for a complete overhaul.

d.Each of its power-generating units is taken off-line for maintenance every one to three weeks.

e.Costs associated with breakdowns are several times higher than costs arising from preventive

maintenance.

d (Global company profile, moderate)

27.The objective of maintenance and reliability is to

a.ensure that breakdowns do not affect the quality of the products

b.ensure that no breakdowns will ever occur

c.ensure that preventive maintenance costs are kept as low as possible

d.maintain the capability of the system

e.ensure that maintenance employees are fully utilized

d (The strategic importance of maintenance and reliability, moderate)

28.The probability that a product will function properly for a specified time under stated conditions is

a.functionality

b.maintenance

c.durability

d.reliability

e.fitness for use

d (The strategic importance of maintenance and reliability, moderate)

29.Which of the following best illustrates the importance of employee involvement in achieving successful maintenance and reliability?

a.Operator, machine, and mechanic are independent of one another.

b.Small standard deviations tend to favor preventive maintenance over breakdown maintenance.

c.Infant mortality in products can be decreased through improved owner's manuals and aftersales service and customer training.

d.Employee involvement through such elements as reward systems and power sharing combine with good maintenance and reliability procedures to improve capacity and reduce variability.

e.Empowered operators have higher competence at repairs than field service or depot service.

d(The strategic importance of maintenance and reliability, moderate)

30.What is the reliability of a four-component product, with components in series, and component reliabilities of .90, .95, .98, and .99?

a.under 0.83

b.at most 0.90

c.0.955

d.no less than .99

e.none of the above

a (Reliability, moderate) {AACSB: Analytic Skills}

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