Test-Bank-for-Heizer-Operations-Management-9e
.pdf76.In assembly line balancing, the minimum number of workstations is
a.the ratio of the sum of all task times to cycle time
b.always (when a fraction) rounded upward to the next larger integer value
c.not always possible to reach when tasks are actually assigned to stations
d.all of the above
e.none of the above
d(Repetitive and product-oriented layout, moderate)
77.In assembly line balancing, cycle time (the ratio of available production time to scheduled production) is the
a.minimum time that a product is allowed at each workstation
b.maximum time that a product is allowed at each workstation
c.optimum time that a product is allowed at each workstation
d.desired cycle time that a product is allowed at each workstation
e.all of the above
b(Repetitive and product-oriented layout, moderate)
78.A production line is to be designed to make 500 El-More dolls per day. Each doll requires 11 activities totaling 16 minutes of work. The factory operates 750 minutes per day. The cycle time for this assembly line is
a.one-half minute
b.one and one-half minutes
c.two minutes
d.5,500 minutes
e.cannot be determined from the information given
b(Repetitive and product-oriented layout, moderate) {AACSB: Analytic Skills}
79.A production line is to be designed for a job with four tasks. The task times are 2.4 minutes, 1.4 minutes, 0.9 minutes, and 1.7 minutes. The maximum cycle time is ______ and the minimum cycle time is ______ minutes.
a.1.8; 1.4
b.1.6; 0.9
c.6.4; 2.4
d.2.4; 0.9
e.none of these
c(Repetitive and product-oriented layout, moderate) {AACSB: Analytic Skills}
80.Cycle time is computed as
a.desired output divided by the daily operating time
b.daily operating time divided by the product of desired output and the sum of job times
c.the product of desired output and the sum of job times divided by daily operating time
d.daily operating time divided by the scheduled output
e.1.00 minus station time
d (Repetitive and product-oriented layout, moderate)
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81.Daily capacity of a product layout is determined by
a.operating time divided by cycle time
b.cycle time divided by operating time
c.operating time divided by total task time
d.total task time divided by cycle time
e.cycle time divided by total task time
a(Repetitive and product-oriented layout, moderate)
82.Four hundred and eighty minutes of production time are available per day. Scheduled production is 120 units per day. What is the cycle time?
a.4 minutes
b.5 minutes
c.6 minutes
d.7 minutes
e.8 minutes
a(Repetitive and product-oriented layout, moderate) {AACSB: Analytic Skills}
83.A production line is to be designed for a product whose completion requires 21 minutes of work. The factory works 400 minutes per day. Can an assembly line with five workstations make 100 units per day?
a.yes, with exactly 100 minutes to spare
b.no, but four workstations would be sufficient
c.no, it will fall short even with a perfectly balanced line
d.yes, but the line's efficiency is very low
e.cannot be determined from the information given
c(Repetitive and product-oriented layout, moderate) {AACSB: Analytic Skills}
84.Four hundred and eighty minutes of production time are available per day. The schedule calls for the production of 80 units per day. Each unit of the product requires 30 minutes of work. What is the theoretical minimum number of workstations?
a.2
b.3
c.4
d.5
e.6
d(Repetitive and product-oriented layout, moderate) {AACSB: Analytic Skills}
85.Which of the following is not a heuristic rule for assigning tasks to workstations in a product layout?
a.longest tasks first
b.in order of most number of following tasks
c.median tasks first
d.shortest tasks first
e.in accordance with positional weight
c (Repetitive and product-oriented layout, moderate)
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86.If a layout problem is solved by use of "heuristics," this means that
a.there was no other way to solve the problem
b.no computer software was available
c.the problem has only a few alternatives to evaluate
d.no optimum solution exists
e.a "satisfactory" solution is acceptable
e(Repetitive and product-oriented layout, moderate)
87.Which of the following is a common heuristic for assembly line balancing?
a.debits near the windows, credits near the door
b.manufacturers locate near materials, retailers locate near customers
c.earliest due date first
d.ranked positional weight
e.none of the above
d(Repetitive and product-oriented layout, moderate)
88.An assembly line consists of 21 tasks grouped into 5 workstations. The sum of the 21 task times is 85 minutes. Cycle time for the line is 20 minutes. The efficiency of this line is
a.4.2 percent
b.17 percent
c.85 percent
d.100 percent
e.none of the above
c (Repetitive and product-oriented layout, moderate) {AACSB: Analytic Skills}
89.An assembly line consists of 158 tasks grouped into 32 workstations. The sum of all task times is 105 minutes. Cycle time for the line is 4 minutes. The efficiency of this line is approximately
a.8 percent
b.21 percent
c.82 percent
d.100 percent
e.none of the above
c (Repetitive and product-oriented layout, moderate) {AACSB: Analytic Skills}
FILL-IN-THE BLANK
90.McDonald's "Made for You" kitchen system represents a ___________ use of layout decisions. strategic (Global company profile, easy)
91.___________ layouts deal with low-volume, high-variety production with like machines and equipment grouped together.
Process-oriented (Process-oriented layout, easy)
92.A(n) __________ is a special product-oriented arrangement of machines and personnel in what is ordinarily a process-oriented facility.
work cell (Process-oriented layout, moderate)
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93.A(n) ___________ groups workers, their equipment, and spaces/offices to provide for comfort, safety, and movement of information.
office layout (Office layout, moderate)
94.The ____________ is a non-numeric method for determining which departments are located near one another, and which departments are kept further apart.
office relationship chart or relationship chart (Office layout, moderate)
95.A(n) ____________ addresses flow, allocates space, and responds to customer behavior. retail layout (Retail layout, moderate)
96.__________ are fees manufacturers pay to get their products displayed.
Slotting fees (Retail layout, moderate)
97.__________ refers to the physical surroundings in which a service takes place, and how they affect customers and employees.
Servicescape (Retail layout, moderate)
98.____________ avoids placing materials or supplies in storage by processing them as they are received for shipment.
Cross-docking (Warehousing and storage layouts, moderate)
99.The project remains in one place and workers and equipment come to that one work area in a
__________ layout.
fixed-position (Retail layout, moderate)
100._______________ is the use of computer software to evaluate the profitability of merchandising plans in a retail layout.
Category management (Retail layout, moderate) {AACSB: Use of IT}
101.__________ is that element of balancing a work cell that superficially resembles cycle time.
Takt time (Work cells, moderate)
102.A(n) ________ line is a machine-paced product-oriented facility for building components. fabrication (Repetitive and product-oriented layout, moderate)
103.___________ is the maximum time that the product is available at each workstation.
Cycle time (Repetitive and product-oriented layout, moderate)
SHORT ANSWERS
104. Identify McDonald's "seven major innovations
The seven major innovations are indoor seating, drive-through windows, breakfast menus, play areas, the "Made for You" kitchen system, the self-service kiosk, and the 21st century look. (Global company profile, moderate)
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105.In what specific areas does the layout decision establish a firm's competitive priorities?
Layout decisions establish a firm’s competitive priorities in the following areas: processes, flexibility, cost, capacity, and quality of work life. (The strategic importance of layout decisions, moderate)
106.To develop a good facility layout, what must be determined?
You need to consider the following to determine a good layout: selection of material handling equipment, capacity and space requirements, environment and aesthetics, flows of information, and cost of moving between various work areas. (Types of layouts, moderate)
107.Identify the seven fundamental layout strategies. Describe the use of each one very briefly.
1.Office layout: Positions workers, their equipment, and spaces/offices to provide for movement of information.
2.Retail layout: Allocates shelf space and responds to customer behavior.
3.Warehouse layout: Addresses trade-offs between space and material handling.
4.Fixed-position layout: Addresses the layout requirements of large, bulky projects such as ships and buildings
5.Process-oriented layout: Deals with low-volume, high-variety production.
6.Work cell layout: Arranges machinery and equipment to focus on the production of a single product or a group of related products
7.Product-oriented layout: Seeks the best personnel and machine utilization in repetitive or continuous production.
(Types of layout, moderate)
108.What techniques can be used to overcome the inherent problems of fixed-position layouts?
Some actions that can be taken to overcome the problems of a fixed-position layout are to develop good schedules, accurately define requirements, and take a rational approach to the layout, as opposed to politicizing the decision. (Fixed-position layout, moderate)
109."Having a focused work center is like having a factory within a factory." Discuss. Include in your discussion what conditions make focused work centers appropriate.
A focused work center is a permanent product-oriented set of equipment within a processoriented facility. It requires group technology or equivalent, a high level of staff training and flexibility, and good support or imagination to get started. (Process-oriented layout, moderate)
110.Why do work cells increase the use of equipment and machinery?
Work cells increase the use of equipment and machinery because of better scheduling and faster material flow. (Process-oriented layout, moderate)
111.What are the advantages of focused factories?
Focused factories are better able to stay in tune with their customers, produce quality products, and operate at higher margins. (Process-oriented layout, moderate)
112.Explain how a load-distance model helps solve problems in process layout.
The problem in process layout is to hold down material movement and material handling. The load-distance model calculates these movements from department to department, and can find that set of departmental space assignments that minimize the aggregate material handling cost. This is an optimal layout for a process layout, given the pattern of loads and distances. (Process-oriented layout, moderate)
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113.Identify the four requirements for cellular production.
(1) identification of families of products, often through the use of group technology codes or equivalents; (2) a high level of training, flexibility, and empowerment of employees; (3) being self-contained, with its own equipment and resources; and (4) test (poka-yoke) at each station in the cell. (Process-oriented layout, moderate)
114.A facilities manager at a company headquarters once said, "I'd like to use Muther's office relationship chart or the load-distance model to solve our layout problems, but neither tool can optimize. I want the best layout possible." Discuss.
The manager should not be so quick to reject models that find satisfactory, but not necessarily optimal, solutions. The load-distance model can optimize relatively small problems, but large problems are beyond the explicit enumeration required for optimization. That's why CRAFT and other software seek "acceptable" solutions. The office relationship diagram is not an optimizing tool at all, as it uses labels, not numbers, to indicate desirability of closeness. (Office layout, moderate) {AACSB: Reflective Thinking}
115.What design guidelines help retail layouts to maximize customer exposure to products?
Design guidelines that help retail layouts maximize customer exposure to products include:
1.locating the high-draw items around the periphery of the store
2.using prominent locations for high-impulse and high-margin items
3.distributing what are known in the trade as "power items" to both sides of an aisle, and dispersing them to increase the viewing of other items
4.using end aisle locations because they have a very high exposure rate
5.conveying the mission of the store by careful selection in the positioning of the lead-off department (Retail layout, moderate)
116.Consider the five ideas for determining the overall arrangement of most retail stores. How are these ideas implemented (a) in a supermarket, and (b) in a fine department store? (Please consider the entire store--not just the areas where merchandise is displayed.)
(Suggested response) The five ideas are: 1. locating the high-draw items around the periphery of the store, 2. using prominent locations for high-impulse and high-margin items, 3. distributing what are known in the trade as "power items" to both sides of an aisle, and dispersing them to increase the viewing of other items, 4. using end aisle locations because they have a very high exposure rate, 5. conveying the image of the store by careful selection in the positioning of the lead-off department. Supermarkets make more use of aisles, where ideas 3 and 4 are featured. Department stores are meandering, so there's less use of end-caps. Both types of retail seem to follow ideas 1 and 5. Idea 2 seems to be implemented with impulse items near the checkouts for both retail types. The supermarket's straight lines convey its strategy of low cost; the department store's display areas convey its focus on image, browsing, etc. (Retail layout, difficult) {AACSB: Reflective Thinking}
117.Briefly explain what "slotting" is. Why is slotting considered a "controversial" practice? What ethical issues might arise with regard to slotting?
Slotting is the practice of manufacturers paying for retail shelf space. It is controversial because some managers approve of the practice, but others do not. Ethical issues involved with slotting are (1) such payments might be considered bribery, (2) such payments cost consumers more, and (3) such payments may interfere with efficient and profitable use of retail space. (Retail layout, difficult) {AACSB: Ethical Reasoning}
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118.What is a servicescape? How is it related to the retail layout problem? What are the three elements of servicescape for dealing with these human issues?
Servicescape describes the physical surroundings in which a service takes place. Rather than design a retail space strictly for profitability, managers must consider how the surroundings—the layout—have a humanistic effect on customers and employees. The three elements are ambient conditions, spatial layout/functionality, and signs, symbols, and artifacts. (Retail layout, moderate)
119.What is cross-docking? Why is it appropriate for some forms of warehouse layout?
Cross-docking avoids placing materials or supplies in storage by processing them as they are received for shipment. It avoids storing the product, saves space and receiving time, and speeds up shipment to the ultimate destination. (Warehousing and storage layouts, moderate)
120.What are the two basic types of product layouts? Explain how they are alike, and how they are different.
The two types are fabrication lines and assembly lines. Fabrication lines build components on a series of machines, while assembly lines put the fabricated parts together at a series of workstations. Fabrication lines tend to be machine paced and require mechanical changes to facilitate balance, while assembly lines tend to be paced by work tasks assigned to individuals or to workstations and are therefore balanced by moving tasks from one individual to another. (Repetitive and product-oriented layout, difficult)
121.Explain what the purpose of assembly line balancing is. Describe briefly how it is done. Explain how assembly line balancing supports the needs of product layout.
Assembly line balancing attempts to put equal amounts of work into each of the workstations that assemble a product. The technique begins with a task list and precedence chart; to this is added demand data, from which cycle time can be computed. This is the speed at which the line must move. Then the theoretical number of stations is calculated. Each required task is then assigned into one workstation. This approach holds down the amount of idle time in a product layout, and leads to higher utilization of the plant, and to higher volume of output. (Repetitive and product-oriented layout, difficult)
122.Define the following terms that occur in assembly line balancing: cycle time, minimum number of workstations, and efficiency.
Cycle time is the ratio of allowed work time to units scheduled. The theoretical minimum number of workstations in an assembly line is determined by dividing the total task-duration time for the product by the cycle time. The efficiency of a line balance is determined by dividing the total task time assigned by the product of the number of workstations times the cycle time. (Repetitive and product-oriented layout, moderate)
123.What is the role of heuristics in solving layout problems? Provide a brief example, drawing from manufacturing situations, retailing situations, or other service situations.
Heuristics are used in problems too complex to model explicitly, such as assembly line balancing problems, fixed-position layouts, office layouts, and retail layouts. All of these layout types are quite complex, featuring very large numbers of alternative solutions and no single numeric objective for evaluating them. (Repetitive and product-oriented layout, moderate)
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124.Assembly line balancing has just been used to solve a product layout problem. Two solutions look especially attractive to the plant managers. Both solutions make the same output per day, and both have the same number of workstations. The managers were going to break the tie by looking at line efficiency, but discovered that both lines had the same efficiency as well. Should they have been surprised at this? Explain.
No, they should not be surprised. Efficiency is the ratio of actual work needed per unit to time available. Work needed is clearly the same in both cases as the product is the same. Work available is also the same, since both lines have the same number of stations and the same cycle time. Once cycle time and number of stations are known, so is efficiency, no matter what tasks are assigned to what stations within that framework. (Repetitive and product-oriented layout, difficult) {AACSB: Analytic Skills}
125.What are the advantages and disadvantages of product layouts?
The advantages of a product layout are:
•The low variable cost per unit usually associated with high-volume, standardized products.
•Low material handling costs.
•Reduced work-in-process inventories.
•Easier training and supervision.
•Rapid throughput.
The disadvantages are:
•The high volume required because of the large investment needed to establish the process.
•That work stoppage at any point ties up the whole operation.
•A lack of flexibility when handling a variety of products or production rates.
(Repetitive and product-oriented layout, moderate)
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PROBLEMS
126.Develop a solution for the following line balancing problem, allowing a cycle time of 5 minutes.
a.Draw the precedence diagram for the set of tasks.
b.Calculate the theoretical minimum number of workstations.
c.Balance this line using the longest task time heuristic.
d.What tasks are assigned to which stations?
e.Does the solution have the minimum number of stations? Explain.
f.How much idle time is there, summed over all workstations?
g.What is the efficiency of this line?
Work Task |
Task Time (seconds) |
Task Predecessor(s) |
A |
70 |
- |
B |
60 |
A |
C |
120 |
B |
D |
60 |
- |
E |
240 |
C, D |
F |
100 |
A |
G |
190 |
E, F |
The minimum number of workstations is 3. Balance places ABDF in station 1, C in station 2, E in station 3, and G in station 4. The solution uses four stations, not three. The POM for Windows solution is shown below. Idle time is distributed 10, 180, 60, and 110 per station. There are 360 seconds of idle time in the system. Efficiency is 70.0%.
(Repetitive and product-oriented layout, moderate) {AACSB: Analytic Skills}
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127.An assembly line has been designed to make battery-powered beverage mixers. Task details are shown in the table below:
Station |
Task Assigned |
Task Time (minutes) |
|
1 |
1 |
|
3.0 |
2 |
3; 4 |
|
1.5; 2.0 |
3 |
2; 5; |
6 |
1.5; 1.5; 1.0 |
4 |
7 |
|
3.0 |
5 |
8 |
|
2.5 |
6 |
9; 10; |
11 |
2.0; 1.0; 1.0 |
a.What is the assigned cycle time (in minutes)?
b.What is the maximum output rate of this line in mixers per hour?
c.What is the total idle time per cycle?
d.What is the assembly line's efficiency?
Cycle time is 4.0 minutes (governed by stations 3 and 6). Maximum output is 60/4 = 15.0 units per hour. Idle time is 1.0 + 0.5 + 0.0 + 1.0 + 1.5 + 0 = 4.0 minutes. Efficiency is 20.0/24.0 = 83.3%. (Repetitive and product-oriented layout, moderate) {AACSB: Analytic Skills}
128.Departments A, B, C, and D need to be assigned to four rooms 1, 2, 3, and 4. These rooms are arranged in a row, in that order, with 20 meters between each. The departmental work flows are contained in the table below.
a.What is the material handling total of assigning A-1, B-2, C-3, D-4?
b.What is the material handling total of assigning A-1, B-3, C-4, D-2?
Flow Matrix
|
Dept. A |
Dept. B |
Dept. C |
Dept. D |
Dept. A |
0 |
30 |
5 |
20 |
Dept. B |
5 |
0 |
40 |
20 |
Dept. C |
0 |
10 |
0 |
40 |
Dept. D |
10 |
5 |
0 |
0 |
(a)The material handling total of A-1, B-2, C-3, D-4 is 5500. Details: 1-2 (A-B): 20x30+20x5=700; 1-3 (A-C): 40x5+40x0=200; 1-4 (A-D): 60x20+60x10=1800; 2-3 (B-C): 20x40+20x10=1000; 2-4 (B-D): 40x20+40x5=1000; and 3-4 (C-D): 20x40+20x0=800. The sum of these six elements is 5,500.
(b) The material handling total of A-1, B-3, C-4, D-2 is 5400, which is also the optimal solution. Details: 1-2 (A-D): 20x20+20x10=600; 1-3 (A-B): 40x30+40x5=1400; 1-4 (A-C): 60x5+60x0=300; 2-3 (B-D): 20x20+20x5=500; 2-4 (C-D):40x40+40x0=1600; and 3-4 (B-C): 20x40+20x10=1000. These six elements sum to 5400. (Process-oriented layout, moderate) {AACSB: Analytic Skills}
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