Deck 10: Waiting Line Analysis and Simulation

Question 1

Gas stations, loading docks, and parking lots have infinite potential length of lines for their respective queuing systems.

Answer 1

False

Question 2

The customer arrivals in a queuing system come almost exclusively from finite populations.

Answer 2

False

Question 3

A tellers' window in a bank is an example of a single-channel, multiphase queuing system.

Answer 3

False

Question 4

An infinite population in waiting line management refers to a population that is large enough in relation to the service system so that the change in population size caused by subtractions or additions to the population does not significantly affect the system probabilities.

Question 5

The customer arrivals in a queuing system come almost exclusively from infinite populations.

Question 6

Arrival characteristics in a queuing problem analysis include the length of the queue.

Question 7

A car wash is an example of a single-channel, multiphase queuing system.

Question 8

The admissions system in a hospital for patients is an example of a single-channel, single-phase queuing system.

Question 9

Highest-profit customer first is a queue discipline discussed in the textbook.

Question 10

The demand on a hospital's emergency medical services is considered an uncontrollable arrival pattern of the calling population.

Question 11

The central problem in virtually every waiting line situation is a decision balancing the costs of adding services with the costs of waiting.

Question 12

A finite population in waiting line management refers to a population that is large enough in relation to the service system so that the change in population size caused by subtractions or additions to the population does not significantly affect the system probabilities.

Question 13

The Poisson probability distribution is used in waiting line management when one is interested in the number of arrivals to a queue during some fixed time period.

Question 14

A variable arrival rate is more common in waiting line management than a constant arrival rate.

Question 15

A constant arrival rate is more common in productive systems than a variable arrival rate.

Question 16

There are different queuing models to fit different queuing situations.

Question 17

The demand on a hospital's emergency medical services is considered a controllable arrival pattern of the calling population.

Question 18

Best customer last is a queue discipline discussed in the textbook.

Question 19

Longest waiting time in line is a queue discipline discussed in the textbook.

Question 20

Ideally, in waiting line or queuing analysis, we want to balance the cost of service capacity with the cost of waiting.

Question 21

Being user-friendly and easy to understand is considered a desirable feature of simulation software systems.

Question 22

Special-purpose simulation software is specially built to run specific applications and may have provisions in manufacturing models to allow for specifying the number of workcenters, their descriptions, arrival rates, and even batch sizes.

Question 23

The more time, money, and effort you spend developing a simulation model, the more likely you are to achieve useful results.

Question 24

Which of the following is not a suggestion for managing queues presented in the textbook?

A)Try to divert your customer's attention when waiting.
B)Segment the customers.
C)Encourage customers to come during the slack periods.
D)Train your people to be friendly.
E)Periodically close the service channel to temporarily disperse the line.

Question 25

The leading general- and special-purpose simulation models follow a well-documented and standardized approach.

Question 26

In a department 25 machines are kept running by three operators who respond to randomly occurring equipment problems.

Question 27

General-purpose simulation software (GPSS) is really a computer language that allows programmers to build their own simulation models.

Question 28

Having animation capabilities to graphically display product flows through a production system is not considered a desirable feature of simulation software systems.

Question 29

In a department 25 machines are kept running by three operators who respond to randomly occurring equipment problems.

Question 30

Being able to permit interactive debugging of a model so the user can trace flows through the model and more easily find errors is considered a desirable feature of simulation software systems.

Question 31

Regardless of the computer language chosen for a simulation model, too much data from a simulation can be dysfunctional to problem solving.

Question 32

Spreadsheet simulations have become obsolete due in part to specialized computer simulation languages like SLAM or SIMAN.

Question 33

While spreadsheets can be somewhat useful for a variety of simulation problems, they can be confusing and are vulnerable to several drawbacks, including weak routines for random-number selection.

Question 34

Which of the following is a suggestion for managing queues that is mentioned in the textbook?

A)Put up a serpentine lane to keep people from jumping ahead in line.
B)Use humor to defuse a potentially irritating situation.
C)Segment the customers.
D)Assure customers that the wait is fair, and inform them of the queue discipline.
E)Tell people in the queue that each will be served as soon as possible.

Question 35

Being user-friendly and easy to understand typically means that the simulation produces less accurate results.

Question 36

In a practical sense, a finite population is one that potentially would form a very long line in relation to the capacity of the serving system.

Question 37

In a department, 25 machines are kept running by three operators who respond to randomly occurring equipment problems.

Question 38

In a waiting line situation, multiple lines occur only when there are multiple servers.

Question 39

The term "queue discipline" involves the art of controlling surly and unruly customers who have become irritated by waiting.

Question 40

In a practical sense, an infinite queue is one that includes every possible member of the served population.

Question 41

A roller coaster ride in an amusement park employs which type of queuing system line structure?

A)Single channel, single phase
B)Single channel, multiphase
C)Multichannel, single phase
D)Multichannel, multiphase
E)None of these

Question 42

In modeling a simulation, random numbers from 00 to 99 are assigned with the intervals determined from frequency distributions for each behavior occurrence.Assume there are two behaviors, A and B, out of 100 tallies.On behavior A you record 45 tallies, and on behavior B you record 55 tallies.Which of the following is a correct random-number interval for behavior A?

A)00 to 45
B)00 to 44
C)56 to 99
D)55 to 100
E)45 to 100

Question 43

Which of the following is not a queue discipline discussed in the textbook?

A)First come, first served
B)Last in, first out
C)Limited needs
D)Shortest processing time
E)Best customer first

Question 44

A company is concerned about the number of customers who have to wait for service in its customer service department.Assume the rate at which customers are serviced is 12 per hour.Using the infinite queuing notion for the models presented in the textbook, which of the following is the mean time between arrivals?

A)12 minutes
B)6 minutes
C)2 minutes
D)1 minute
E)None of these

Question 45

Which of the following is not a suggestion for managing queues presented in the textbook?

A)Train your servers to be friendly.
B)Segment the customers.
C)Determine an acceptable waiting time for your customers.
D)Inform your customers of what to expect.
E)Encourage customers to come during slack periods.

Question 46

Which of the following is a suggestion for managing queues presented in the textbook?

A)Train your servers to be friendly.
B)Tell customers that the line should encourage them to come during slack periods.
C)Give each customer a number.
D)Periodically close the service channel to temporarily disperse the line.
E)Use humor to defuse a potentially irritating situation.

Question 47

Buying food at a large food store with multiple checkout counters features which type of queuing system line structure?

A)Single channel, single phase
B)Single channel, multiphase
C)Multichannel, single phase
D)Multichannel, multiphase
E)None of these

Question 48

Which of the following is an example of a finite population in a queuing system?

A)People waiting to place their order at a fast-food restaurant
B)The departmental faculty in line at the copier
C)People waiting in line at an ATM
D)Patients seeking help in a hospital emergency room
E)Taxpayers calling for assistance from the IRS

Question 49

Which of the following is a suggestion for managing queues that is mentioned in the textbook?

A)Put up a serpentine lane to keep people from jumping ahead in line.
B)Use humor to defuse a potentially irritating situation.
C)Train your servers to be friendly.
D)Assure customers that the wait is fair, and inform them of the queue discipline.
E)Tell people in the queue that each will be served as soon as possible.

Question 50

Getting an autograph from a famous person might involve standing in which type of queuing line structure?

A)Single channel, single phase
B)Single channel, multiphase
C)Multichannel, single phase
D)Multichannel, multiphase
E)None of these

Question 51

For an infinite queuing situation, if the arrival rate for loading trucks is 5 trucks per hour, what is the mean time between arrivals?

A)5 hours
B)2.5 hours
C)0.2 hour
D)0.1 hour
E)None of these

Question 52

Which of the following are the three major components of a queuing system?

A)The source population, how customers exit the system, and the queuing discipline
B)The number of servers, the service speed, and the waiting line
C)The source population, how the customer exits the system, and the servicing system
D)The source population and the way customers arrive at the system, the serving systems, and how customers exit the system
E)The service speed, the queue discipline, and the waiting line

Question 53

Machine breakdown and repair in a 12-machine factory having three repair mechanics would develop which type of queuing system line structure concerning machine breakdowns?

A)Single channel, single phase
B)Single channel, multiphase
C)Multichannel, single phase
D)Multichannel, multiphase
E)None of these

Question 54

In essence, a queuing system includes several major components.Which of the following is not one of them?

A)Source population
B)Servicing system
C)How the customer exits the system
D)The queue discipline
E)None of these

Question 55

Machine breakdown and repair in a 12-machine factory having one repair mechanic would develop which type of queuing system line structure concerning machine breakdowns?

A)Single channel, single phase
B)Single channel, multiphase
C)Multichannel, single phase
D)Multichannel, multiphase
E)None of these

Question 56

Buying a ticket for a college football game where there are multiple windows at which to buy the ticket features which type of queuing system line structure?

A)Single channel, single phase
B)Single channel, multiphase
C)Multichannel, single phase
D)Multichannel, multiphase
E)None of these

Question 57

Assume the service rate for a queue in a truck-loading operation is 2 trucks per hour.Using the infinite queuing notion for the models presented in the textbook, which of the following is the average service time?

A)2 hours
B)1 hour
C)0.5 hour
D)0.25 hour
E)None of these

Question 58

Which of the following queue disciplines is discussed in the textbook?

A)Emergencies first
B)Garner-Whitten formula
C)Newest customer first
D)Patient customers last
E)None of these

Question 59

Standing in line to buy a ticket for a movie where there are multiple windows at which to buy tickets is which type of queuing system line structure?

A)Single channel, single phase
B)Single channel, multiphase
C)Multichannel, single phase
D)Multichannel, multiphase
E)None of these

Question 60

In a college registration process, several department heads have to approve an individual student's semester course load.What is the queuing system line structure?

A)Single channel, single phase
B)Single channel, multiphase
C)Multichannel, single phase
D)Multichannel, multiphase
E)None of these

Question 61

In modeling a simulation, random numbers from 00 to 99 are assigned with the intervals determined from frequency distributions for each behavior occurrence.Assume there are two behaviors, A and B, out of 50 tallies.On behavior A you record 15 tallies, and on behavior B you record 35 tallies.Which of the following is a correct random-number interval for behavior A (Choose the most appropriate answer)?

A)00 to 29
B)00 to 14
C)70 to 99
D)35 to 49
E)A or C

Question 62

A small vendor has either a good day of sales with an average of $1,000 or a bad day with an average of only $500 for the day.To simulate these outcomes, random numbers from 00 to 99 should be assigned with the intervals determined from the frequency distribution.If, during the last 100 days, the vendor had 27 good days and 73 bad days, which of the following is a correct random-number interval for a bad day?

A)28 to 99
B)27 to 73
C)27 to 100
D)27 to 99
E)00 to 26

Question 63

Assuming a 24 hour operation in a warehouse, and an arrival following Poisson distribution with mean rate of 36 per day and service (unloading using a single bay) following exponential with a rate of 48 trucks per day, answer the following question.What is the expected number of trucks in the system?

A)2.25
B)1.5
C)2
D)1
E)3

Question 64

In modeling a simulation, random numbers from 00 to 99 are assigned with the intervals determined from frequency distributions for each behavior occurrence.Assume there are two behaviors, X and Y, out of 50 tallies.On behavior X you record 20 tallies, and on behavior Y you record 30 tallies.Which of the following is a correct random-number interval for behavior X?

A)00 to 19
B)01 to 20
C)00 to 39
D)41 to 61
E)45 to 100

Question 65

Which of the following is an example of general-purpose simulation software?

A)PC-MODEL
B)MAP/1
C)SIMFACTORY
D)Canella IV
E)OPUS/2.3

Question 66

Customers arrive at a single self-serve coffee machine in a busy mall at the rate of 20 per hour, following Poisson distribution.Each customer takes exactly 90 seconds to get his or her coffee.What is the expected number of customers in queue at this coffee machine?

A)1.0
B)1.5
C)0.5
D)2.0
E)3.0

Question 67

Which of the following is an example of general-purpose simulation software?

A)Link Trainer Programs
B)SIMSCRIPT II.5
C)SIM-Central
D)C++
E)Visual Basic

Question 68

Assuming a 24 hour operation in a warehouse, and an arrival following Poisson distribution with mean rate of 36 per day and service (unloading using a single bay) following exponential distribution with a rate of 48 trucks per day, answer the following question.What is the expected waiting time in the system (in hours) for a typical truck?

A)2 hours
B)1 hour
C)1.5 hour
D)0.25 hour
E)0.5 hours

Question 69

Which of the following is not an example of general-purpose simulation software?

A)SIMAN
B)GPSS/PC
C)RESQ
D)GAPE/H
E)SLAMII

Question 70

Customers arrive at a common queue at the coffee station with two identical coffee machines in a busy mall at the rate of 48 per hour, following Poisson distribution.Each customer mixes his or her specialty coffee taking 2 minutes on an average following an exponential process.What is the expected number of customers in the system at this coffee station?

A)infinity
B)2.844
C)2.444
D)4.444
E)3