EXAM 1

Question 1

Which fundamental measures of traffic flow can be measured at a fixed point?

Answer 1

Flow & Speed

Question 2

Which fundamental measures of traffic flow can be measured over a section?

Answer 2

Density & Speed

Question 3

With respect to the Poisson Model, the probability of no vehicle arriving in a certain time interval.

Answer 3

Is indirectly proportional to the length of the time interval.

Question 4

When considering heavy vehicles in level of service analysis, why are RVs (recreational vehicles) treated differently from trucks and buses?

Answer 4

RV’s are typically driven from personal reasons by drivers who may be unfamiliar with the roads. Trucks & buses are typically drive for commercial reasons by professional drivers.

Question 5

Priority service methods are sometimes used in queueing situations in transportation to provide special treatment for certain types of users. What is an example of such priority service?

Answer 5

HOV (high occupany vehicle) lanes, E-Z pass at toll booths, bus only lanes

Question 6

Queueing diagrams should only be used for calculating que lengths and delay times for what ytpe of queues?

Answer 6

oversaturated or capacitated queues

Question 7

With respect to uncapactiated queues, on what does the utilization depend?

Answer 7

Utilization depends on the arrival & departure rates

Question 8

Traffice control devices are used to provide three types of communication with the users. They are:

Answer 8

Regulate, warn, direct

Question 9

The effective green time for one full traffic signal cycle is the difference between which two values?

Answer 9

Cycle length, lost time for the cycle.

Question 10

When considering the amount of time it takes to go from an origin to a destination, the total travel time can be divided into these two categories:

Answer 10

In-vehicle travel time & out-of vehicle travel time

Question 11

Transport facilities provide these two distinct functions: (different roads have different distributions of these functions)

Answer 11

Land access & Movement (or mobility)

Question 12

Explain why redudancies in a transportation system can a good thing.

Answer 12

Redundencies in a transportation system can increase reliability by providing duplications of critical facilities. If one part of the system fails, then another part can help make up for it ad prevent system failure.

Question 13

Explain why redundancies in a trnasportation sytem can be a bad thing.

Answer 13

Too much redundancies can be politically expensive to build and maintain. Further, in transportation system, more redundancies may mean a greater proportion of land being used for transport instead of other productive uses.

Question 14

In a mode choice model, a decision maker n is asumed to choose between i alternatives. How many attributes can be used in such a model to describe each alternative?

a) 1
b) i
c) As many as can be measured
d) None of the above

Answer 14

C) as many as can be measured

Question 15

In one route choice model, users of a transportation system are assumed to use the route with the shortest travel time for their trips. What is the definition of equilirbium for the static approach in considering route choice in such a model?

Answer 15

Equilibrium is the state in which the travellers on all routes between two places experience the same travel time.