Question 1

Server utilization is the:

Accepted Answer

A) amount of time a typical server is busy 
B) fraction of time a typical server is busy 
C) number of servers being used in a system 
D) number of times a server is used in a system 
A) amount of time a typical server is busy 
B) fraction of time a typical server is busy 
C) number of servers being used in a system 
D) number of times a server is used in a system

Question 2

Exponentially distributed service times are often more realistic than exponentially distributed interarrival times.

Accepted Answer

A) True 
 B)False

Question 3

A queuing system where customers join a single line and then are served by the first available server are said to be:

Accepted Answer

A) in parallel 
B) in series 
C) random 
D) networked 
A) in parallel 
B) in series 
C) random 
D) networked

Question 4

Exhibit 13-1A grocery store manager would like to use an analytical queueing model to study the lines of customers that form in front of the checkout stations in the store. During a period of time when business is steady, several store employees have gathered data on customer interarrival times, which are shown below.
  
-[Part 1] Refer to Exhibit 13-1. Is it reasonable to assume exponentially distributed interarrival times for the grocery store customers? If so, what is λ?

Accepted Answer

The histogram of the data (sho

Question 5

Exhibit 13-3A Credit Union has a small branch in which a single customer service representative serves the needs of customers who arrive at an average rate of 24 per hour. The service representative can typically handle 30 customers per hour. Based on an analysis of historical data, it is reasonable to assume that customer interarrival times and service times are exponentially distributed. Assume that all arriving customers enter the branch, regardless of the number already waiting in line.
-Refer to Exhibit 13-3. What percentage of all customers have to spend at least some small amount of time waiting in line?

Accepted Answer

% waiting in queue =

Question 6

As the traffic intensity approaches 1:

Accepted Answer

A) there is no waiting 
B) waiting lines stabilize 
C) waiting lines grow extremely rapidly 
D) at least one server will be idle 
A) there is no waiting 
B) waiting lines stabilize 
C) waiting lines grow extremely rapidly 
D) at least one server will be idle

Question 7

The server utilization U in an M/M/s system is always the same as the traffic intensity.

Accepted Answer

A) True 
 B)False

Question 8

The parameter λ in an exponential distribution can be interpreted as a:

Accepted Answer

A) time 
B) rate 
C) mean 
D) standard deviation 
A) time 
B) rate 
C) mean 
D) standard deviation

Question 9

Exhibit 13-2An oil-change facility serves customers that enter at a rate of 8 per hour. There are five servers available to perform oil changes for entering customers. Customers wait in a single line and enter the facility, in first-come-first-serve fashion, to the first of the five servers who is available. Each server can change the oil of one customer's car every 30 minutes on average.
-Refer to Exhibit 13-2. What is the server utilization?

Accepted Answer

U = Ls / s

Question 10

The exponential distribution is:

Accepted Answer

A) flat 
B) bell-shaped 
C) heavily right-skewed 
D) heavily left-skewed 
A) flat 
B) bell-shaped 
C) heavily right-skewed 
D) heavily left-skewed

Server utilization is the:

Exponentially distributed service times are often more realistic than exponentially distributed interarrival times.

A queuing system where customers join a single line and then are served by the first available server are said to be:

As the traffic intensity approaches 1:

The server utilization U in an M/M/s system is always the same as the traffic intensity.

The parameter λ in an exponential distribution can be interpreted as a:

The exponential distribution is:

Introduction to Modeling

Introduction to Spreadsheet Modeling

Introduction to Optimization Modeling

Linear Programming Models

Network Models

Optimization Models With Integer Variables

Nonlinear Optimization Models

Evolutionary Solver: An Alternative Optimization Procedure

Decision Making Under Uncertainty

Introduction to Simulation Modeling

Simulation Models

Inventory and Supply Chain Models

Regression and Forecasting Models

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Exam 13: Queuing Models

Server utilization is the:

Exponentially distributed service times are often more realistic than exponentially distributed interarrival times.

A queuing system where customers join a single line and then are served by the first available server are said to be:

As the traffic intensity approaches 1:

The server utilization U in an M/M/s system is always the same as the traffic intensity.

The parameter λ in an exponential distribution can be interpreted as a:

The exponential distribution is:

Introduction to Modeling

Introduction to Spreadsheet Modeling

Introduction to Optimization Modeling

Linear Programming Models

Network Models

Optimization Models With Integer Variables

Nonlinear Optimization Models

Evolutionary Solver: An Alternative Optimization Procedure

Decision Making Under Uncertainty

Introduction to Simulation Modeling

Simulation Models

Inventory and Supply Chain Models

Regression and Forecasting Models

Filters