Practical Management Science
6th Edition
ISBN: 9781337406659
Author: WINSTON, Wayne L.
Publisher: Cengage,
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Chapter 12.5, Problem 26P
Summary Introduction
To determine: Whether the three repairers should be replaced with super worker.
Introduction: In order to predict the waiting time and length of the queue, queueing model will be framed. Queueing theory is the mathematical model that can be used for the decision-making process regarding the resources required to provide a service.
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2. A repair and inspection facility consists of two stations: a repair station with two technicians, and
an inspector station with 1 inspector. Each repair technician works at the rate of 3 items per hour; the
inspector can inspect 8 items per hour. Approximately 10% of all items fail inspection and are sent back
to the repair station. (This percentage holds even for items that have been repaired two or more times.) If
items arrive at the rate of 5 per hour, what is the long-run expected delay that items experience at each of
the two stations, assuming a Poisson arrival process and exponentially distributed service times? What is
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A Printed Circuit Board (PCB) machine installs integrated circuits onto a board. Before starting to produce a board, the PCB machine requires a 16-minute setup. Once in production, the PCB machine requires only 0.19 minute per board.
a. Currently, the PCB machine produces 525 boards between setups. Given this operating process, what is the capacity of the PCB machine (in boards per min)?
b. Currently, the PCB machine produces 525 boards between setups. Given this operating process, what is the utilization of the PCB machine?
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Do: 12-21 Truck drivers working for Juhn and Sons (see Problems 12-19 and 12-20) are paid a salary of $20 per hour on average. Fruit loaders receive about $12 per hour. Truck drivers waiting in the queue or at the loading gate are drawing a salary but are productively idle and unable to generate revenue during that time. What would be the hourly cost savings to the firm associated with employing two loaders instead of one?
Not this: 12-19 Juhn and Sons Wholesale Fruit Distributors employs one worker whose job is to load fruit on outgoing company trucks. Trucks arrive at the loading gate at an average of 24 per day, or 3 per hour, according to a Poisson distribution. The worker loads them at a rate of 4 per hour, following approximately the exponential distribution in service times.
Not this: 2-20 Juhn believes that adding a second fruit loader will substantially improve the firm’s efficiency. He estimates that a two-person crew, still acting like a single-server system, at the loading…
Chapter 12 Solutions
Practical Management Science
Ch. 12.3 - Prob. 1PCh. 12.3 - Explain the basic relationship between the...Ch. 12.3 - Prob. 3PCh. 12.3 - Prob. 4PCh. 12.4 - Prob. 5PCh. 12.4 - Prob. 6PCh. 12.4 - Prob. 7PCh. 12.4 - Prob. 8PCh. 12.5 - Prob. 9PCh. 12.5 - Prob. 10P
Ch. 12.5 - Prob. 11PCh. 12.5 - Prob. 12PCh. 12.5 - Prob. 13PCh. 12.5 - Prob. 14PCh. 12.5 - Prob. 15PCh. 12.5 - Prob. 16PCh. 12.5 - Prob. 17PCh. 12.5 - Prob. 18PCh. 12.5 - Prob. 19PCh. 12.5 - Prob. 20PCh. 12.5 - Prob. 21PCh. 12.5 - Prob. 22PCh. 12.5 - On average, 100 customers arrive per hour at the...Ch. 12.5 - Prob. 24PCh. 12.5 - Prob. 25PCh. 12.5 - Prob. 26PCh. 12.5 - Prob. 27PCh. 12.5 - Prob. 28PCh. 12.5 - Prob. 29PCh. 12.5 - Prob. 30PCh. 12.5 - Prob. 31PCh. 12.5 - Prob. 32PCh. 12.5 - Prob. 33PCh. 12.5 - Prob. 34PCh. 12.5 - Prob. 35PCh. 12.5 - Two one-barber shops sit side by side in Dunkirk...Ch. 12.5 - Prob. 37PCh. 12 - Prob. 46PCh. 12 - Prob. 47PCh. 12 - Prob. 48PCh. 12 - Prob. 49PCh. 12 - Prob. 50PCh. 12 - Prob. 51PCh. 12 - Prob. 52PCh. 12 - Prob. 54PCh. 12 - Prob. 56PCh. 12 - Prob. 57PCh. 12 - Prob. 58PCh. 12 - Prob. 59PCh. 12 - Prob. 60PCh. 12 - Prob. 61P
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