Exam 24: Waiting-Line Models

A waiting-line system that meets the assumptions of M/M/S has λ = 5,μ = 4,and M = 2.For these values,Po is approximately 0.23077 and Ls is approximately 2.05128.The average number of units waiting in the queue

In queuing problems,which of the following probability distributions is typically used to describe the number of arrivals per unit of time?

Four of the most widely used waiting line models-M/M/1 or A,M/M/S or B,M/D/1 or C,and Limited population or D-all share three characteristics,which are

A waiting-line system that meets the assumptions of M/M/1 has λ = 1,μ = 4.For this system,the probability of fewer than two units in the system is approximately

A finite population waiting line model has an average service time T of 200 minutes and an average time between service requirements U of 300 minutes;the service factor X is

The ________ probability distribution is a continuous probability distribution often used to describe the service time in a queuing system.

LIFS (last-in,first-served)is a common queue discipline,most often seen where people,not objects,form the waiting line.

What are the components in a waiting-line system?

Arrivals or inputs to a waiting-line system have characteristics that include

There is only one bay and one type of service at an automatic car wash.Provide the most likely characteristics of this system. a.name of model b.number of channels c.number of phases d.arrival rate distribution e.service time distribution f.population size g.queue discipline

In a repetitive focus factory,the number of channels available for the processing of a certain part would likely refer to

A queuing model which follows the M/M/1 assumptions has λ = 2 and μ = 3.The average waiting time in the system is

A waiting line meeting the M/M/1 assumptions has an arrival rate of 4 per hour and a service rate of 12 per hour.What is the average time a unit spends in the system and the average time a unit spends waiting?

Which of the following is a measure of queue performance?

A(n)________ occurs when an arrival refuses to enter a waiting line;a(n)________ occurs when an arrival joins a waiting line,then leaves it.

The potential restaurant customer who says to her husband,"The line looks too long;let's eat somewhere else," is an illustration of which element of queue discipline?

A waiting line model meeting the assumptions of M/M/1 has an arrival rate of 2 per hour and a service rate of 6 per hour;the utilization factor for the system is approximately

In an earlier chapter,you were introduced to a "traditional" view of costs and a "full cost" view of costs,with respect to a certain type of analysis.How might that lesson apply here? In particular,might operations managers pay more attention to some kinds of costs than others?

A system in which the customer receives service from only one station and then exits the system is

A copy centre has five machines that serve many customers throughout the day;the waiting-line system for copy service has an infinite population while the waiting-line system for copier maintenance has a finite population.