Fundamentals of Transportation/Queueing/Additional Problems

Additional Questions

 * 1) What is a queue?
 * 2) Give examples of queueing in real life.
 * 3) What important variables affect queue length.
 * 4) How do you compute total delay from a Newell Curve? What is vehicle delay? How many vehicles are there in the system at a given time.
 * 5) What are some difficulties with calculating queueing times?
 * 6) Define over and under-saturated?
 * 7) Characterize a queue.
 * 8) Define arrival and service rates.
 * 9) If arrival rates > departure rates, what does that imply.
 * 10) Name three types of statistical distributions that describe the behavior of queues and explain them.
 * 11) Can queueing in succession of a length of road mediate arrival demand which reduces delay?
 * 12) Define congestion.
 * 13) Explain the bus bunching idea in relation to queue.
 * 14) How can you determine if a channel is saturated?
 * 15) What is a loop detector?
 * 16) How do loop detectors communicate with stop lights?
 * 17) How do large vehicles affect queue detectors?
 * 18) When does departure rate depend upon arrival rate?
 * 19) What are examples of service methods?
 * 20) What is the effect of controls systems in series?
 * 21) What is the difference between over and undersaturated queues? Give an example of an oversaturated queue.
 * 22) What is the difference between uncapacitated and capacitated queues?
 * 23) What does the variable ρ mean? What is meant when λ > μ, λ < μ
 * 24) Why is there random congestion if the hourly flow is less than hourly capacity (ρ < 1)?
 * 25) How can constraints be included in predicting how many vehicles are expected in a queue? (i.e. capacity of queue)
 * 26) What happens if the average number of cars exceeds ramp capacity?
 * 27) Do equations change for uncapacitated to capacitated queues?
 * 28) How do you calculate the expected number of units in the system?
 * 29) Explain why E(n) ≠ E(m) in words. Why is the average number of units in the system not the same as the mean queue length?
 * 30) Is the expected number of units in the system an average number of units?
 * 31) When μ and λ are random, what kind of queue is it?
 * 32) What does Poisson refer to?
 * 33) What happens to travel time as arrivals approach capacity?
 * 34) Are most systems under or oversaturated in general?
 * 35) What is the average service time?
 * 36) Graph average travel time vs. rho. How does this relate to the volume delay function in Route Choice.
 * 37) How accurate are these formulas for probability of waiting time and queue length?

Additional Problems

 * 1) What is probability you will wait 15 minutes or more if on average 15 cars/min arrive and 14 cars/min are serviced
 * 2) What is the average waiting time if there is a 600 vph arrival rate, and a 500 vph service rate.
 * 3) If there is an arrival rate of 100 vehicles per hour, what is the service time?
 * 4) How would you solve for an average time waiting in queue if the arrival rate is 400 vph and service rate is 450 vph?
 * 5) If the arrival rate is 250 vph and the service rate is 600 vph, what is the time for vehicles waiting to get on the system?
 * 6) With the arrival rate of 250 vph and service rate of 275 vph, ho wmuch free time is there on a ramp and how long is the average wait time.
 * 7) Calculate the average number of vehicles (wait) in the system with x arrivals and y departures.

/Additional Problems