Operations Management
13th Edition
ISBN: 9781259667473
Author: William J Stevenson
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 4.S, Problem 7P
A production line has three machines A, B, and C, with reliabilities of .99, .96, and .93, respectively. The machine are arrange to that if one breaks down, the other: must shut down. Engineers are weighing two alternative designs for the line’s reliability. Plan 1 involve adding an identical backup line, and plan 2 involves providing a backup for each machine. In either case, three machines (A, B, and C) would be used with reliabilities equal to the original three.
a. Which plan will provide the higher reliability?
b. Explain why the two reliabilities are not the same.
c. What other factors might enter into the decision of which plan to adopt?
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A production line has three machines A, B, and C, with reliabilities of 90, 95, and 94, respectively. The machines are arranged so that
if one breaks down, the others must shut down. Engineers are weighing two alternative designs for increasing the line's reliability. Plan
1 involves adding an identical backup line, and plan 2 involves providing a backup for each machine. In either case, three machines (A.
B. and C) would be used with reliabilities equal to the original three.
a. Compute overall system reliability under Plan 1. (Round your intermediate calculations and final answer to 4 decimal places.)
Answer is complete but not entirely correct.
Reliability
0.9859
b. Compute overall system reliability under Plan 2 (Round your intermediate calculations and final answer to 4 decimal places.)
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0.98
Data Storage Module
0.999
Learning Module
0.99
Vision Module
0.94
What is the probability that the system will be up and running?
Suppose this number is too low and it is desired to improve the reliability
through redundant elements.
What would be the new reliability from each one of these changes?
a. back up the Vision module with an identical module.
b. back up the movement module with an identical module, but not the vision module.
Assume that a computer has two 1TB disks, D0 and D1. The Mean Time to Failure (MTTF) ofeach disk is 1M hours.a. If the disk system is configured to have 2TB total storage capacity, when any of the two disksfails, the disk system fails. What is the MTTF of the disk system?b. Mirroring (RAID-1) is a technique can improve the reliability of disk systems by usingredundancy. Each data block will have two identical copies stored in both D0 and D1. Under thisconfiguration, the disk system has only 1TB total storage capacity; but it only fails when bothdisks fail (e.g. when the failed disk is being repaired, the second disk also fails). If the MTTR of afailed disk is 20 hours, what is the MTTF of the disk system now?
Chapter 4 Solutions
Operations Management
Ch. 4.4 - Prob. 1.1RQCh. 4.4 - Prob. 1.2RQCh. 4.8 - LEGO A/S IN THE PINK Lego A/S overcame the recent...Ch. 4.8 - Prob. 2.1RQCh. 4.8 - Prob. 2.2RQCh. 4.11 - THE CHALLENGES OF MANAGING SERVICES Services can...Ch. 4.11 - THE CHALLENGES OF MANAGING SERVICES Services can...Ch. 4.S - Prob. 1DRQCh. 4.S - Prob. 2DRQCh. 4.S - Prob. 3DRQ
Ch. 4.S - Consider the following system: Determine the...Ch. 4.S - A product is composed of four parts. In order for...Ch. 4.S - A system consists of three identical components....Ch. 4.S - A product engineer has developed the following...Ch. 4.S - The guidance system of a ship is controlled by a...Ch. 4.S - One of the industrial robots designed by a leading...Ch. 4.S - A production line has three machines A, B, and C,...Ch. 4.S - Prob. 8PCh. 4.S - A Web server has five major components that must...Ch. 4.S - Repeat Problem 9 under the condition that one of...Ch. 4.S - Hoping to increase the chances of reaching a...Ch. 4.S - An electronic chess game has a useful life that is...Ch. 4.S - A manufacturer of programmable calculators is...Ch. 4.S - Lucky Lumen light bulbs have an expected life that...Ch. 4.S - Prob. 15PCh. 4.S - Prob. 16PCh. 4.S - A major television manufacturer has determined...Ch. 4.S - Prob. 18PCh. 4.S - Determine the availability for each of these...Ch. 4.S - Prob. 20PCh. 4.S - A manager must decide between two machines. The...Ch. 4.S - Prob. 22PCh. 4.S - Auto batteries have an average life of 2.7 years....Ch. 4 - Prob. 1DRQCh. 4 - Prob. 2DRQCh. 4 - Prob. 3DRQCh. 4 - Prob. 4DRQCh. 4 - Prob. 5DRQCh. 4 - Prob. 6DRQCh. 4 - Prob. 7DRQCh. 4 - Prob. 8DRQCh. 4 - a. What is meant by the term life cycle? b. Why...Ch. 4 - Prob. 10DRQCh. 4 - Prob. 11DRQCh. 4 - Prob. 12DRQCh. 4 - Prob. 13DRQCh. 4 - Explain what quality function development is and...Ch. 4 - Prob. 15DRQCh. 4 - Prob. 16DRQCh. 4 - Prob. 17DRQCh. 4 - Prob. 18DRQCh. 4 - Prob. 19DRQCh. 4 - Describe some of the trade-off that are...Ch. 4 - Prob. 2TSCh. 4 - Prob. 3TSCh. 4 - Prob. 1CTECh. 4 - Prob. 2CTECh. 4 - Prob. 3CTECh. 4 - Prob. 4CTECh. 4 - Prob. 5CTECh. 4 - Give two examples of unethical conduct involving...Ch. 4 - Prob. 1PCh. 4 - Prob. 2PCh. 4 - Prepare a service blueprint for each of these...Ch. 4 - Prepare a service blueprint for each of these post...Ch. 4 - Prob. 5PCh. 4 - Prob. 6PCh. 4 - Prob. 7PCh. 4 - Prepare a table similar to that shown in Problem...
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, operations-management and related others by exploring similar questions and additional content below.Similar questions
- Assume Bristol-Myers Squibb is faced with one source of business risk as worker's injury. The probability of worker injury is 0.09 and when the accident (injury) happens, the losses from a worker's injury has medical expenses of $8,000 and lost pay expenses of $90,000. What is the expected loss per worker? A-- $8,820 B-- $7,056 C-- none of the answers is correct D-- $7,417 E-- $17,640arrow_forwardA typical retail transaction consists of severalsmaller steps, which can be considered components subject tofailure. A list of such components might include: Let the eight probabilities of success be .92, .94, .99, .99, .98,.97, .95, and .96. What is the reliability of the system; thatis, the probability that there will be a satisfied customer? Ifyou were the store manager, what do you think should bean acceptable value for this probability? Which componentswould be good candidates for backup, which for redesign?arrow_forwardA plastic injection molding machine operates 334 days a year. It is the bottleneck workstation in a process that produces plastic housed wall clocks. Industrial engineers collected data on the probability of machine breakdowns, the costs of preventive maintenance, and the cost of a breakdown. Number of Molding Machine Breakdowns per Day Probability of a breakdown 0 0.32 1 0.27 2 0.22 3 0.13 4 0.06 The cost of preventive maintenance is high due to performing it between 1 and 4 a.m. each day by two machine experts. The preventive maintenance cost is $2,030 per day including replacement parts, cleaning, and software upgrades. The cost of a breakdown of $1,940 is also high because the downstream workstations can only work until all work-in-progress inventory is completed; then the entire process must stop. What are the economics of the situation? Do not round intermediate calculations. Round your answers to the nearest cent. The expected cost of a breakdown per day is $ The manufacturing…arrow_forward
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