TRANSYSPLAN
These are technologies, employed by the study team, which are selected/permitted by drivers or feet operators. Each of the resulting speed and delay measures may be treated to statistical analyses
Probe vehicle methods
In this technique test vehicle travels according to the driver's judgment of the average speed of the trafic stream
Average Car Technique
These are among the most commonstudies in transportation engineering
Intersection and driveway studies
An example of this probe method are electronic toll-road tags
AVI Transponders
It is the component of delay that results when geometric features cause users to reduce their speed in negotiating a facility
Geometric delay
It occurs between the time the green signal begins, and the queue begins moving eficiently
Startup lost time
This is the triangular area that should be clear of obstructions for any approaching vehicles so drivers can see potentially conficting vehicles in suficient time to stop before colliding within the intersection
Approach Sight Triangle
This estimate travel times by applying spot speeds across shore segments
Extrapolation Method
This is the triangular area that should be clear of obstructions for any departing vehicles stopped at the intersection and trying to enter or cross the major road
Departure Sight Triangle
It is the available time in seconds between two successive vehicles at the same point in space, measured from the rear bumper of the lead vehicle to the front bumper of the following vehicle
Gap
It is the diference between the time a vehicle passes a point downstream of the intersection where it has regained normal speed and the time it would have passed that point had it been able to continue through the intersection at its approach speed
Travel-time delay
This uses a receiving antenna network and electronic transponders within vehicles
Ground-based Radio Navigation
In this technique driver "floats" with the trafic by attempting to safely pass as many vehicles as possible
Floating-Car Technique
It is the time elapsed between the arrival of a minor street vehicle ready to move into the major street and the arrival of the front bumper of the next vehicle in the major trafic stream
Lag
It requires the analyst to use a vehicle to make runs on the roadway segment of interest
Test vehicle method
It is the number of vehicles that can pass a given point on a highway in a given period of time with no interruptions
Saturation flow
This method produces travel time only, from which average travel speed may be calculated once the distance between observation points is measured
License Plate Method
This involve selected individuals who are willing to cooperate may provide a satisfactory sample from which to obtain travel times and delays without the use of a test vehicle or observers
Interview Method
These are technologies that are employed by the study team, which will select which vehicles will be observed, and nonintrusively study them
Vehicle observation methods
It is the component of delay that results when a control signal causes a lane group to reduce speed or to stop; it is measured by comparison with the uncontrolled condition
Control delay
This data can help determine the necessary length of storage lanes or can provide a useful measure of trafic signal eficiency
Queue length
This technology operates by feet vehicles receiving time stamped identifcation data from signpost mounted electronic transmitters
Signpost-based Transponders
It occurs between the time the last vehicle crosses the stop bar, and the next signal phase begins
Clearance lost time
It is a probe technique that utilizes satellites orbiting the earth to transmit positional data to equipped vehicles
GPS
It requires data on the gaps presented in the major trafic stream
Gap acceptance study
In this technique the test vehicle is driven at the posted speed limit unless impeded by actual trafic conditions or safety considerations
Maximum-Car Technique
It is used to connect devices including cellular phones, car radios and computers
Wireless Technology Method
It is the unused portion of the signal cycle
Lost time
In the test vehicle method, once you found the number of samples required, you need to restart data gathering from the beginning
False
To determine the saturation fow rate, the observer stops the watch when the front axle of the seventh, eighth, ninth, or 10th vehicle in the queue
False, Front -> Rear
The interview method is a variation on the average-car method, except that in place of multiple test vehicle there is only a single test vehicle
False, Multiple & Single -> Single & Multiple
The 104 vehicles per hour is the typical value for standard deviation for determining the sample size needed to estimate the saturation fow rate
False, 104 -> 140
Travel time varies directly with travel speed
False, Directly -> Inversely
After doing an initial run of 20 observations, the study team was able to determine the required sample size which is 80. This team needed to perform 80 more observations to satisfy the requirements
False, 80 more -> 60 more
In transportation planning and highway needs studies the allowable error are in the range of: ± 3.0 to ± 5.0 kph
False, kph -> mph
In before-and-after studies the allowable error are in the range of: ± 1.0 to ± 3.0 mph
True
In trafic operations, trend analysis and economic evaluations the allowable error are in the range of: ± 2.0 to ± 4.0 mph
True
After doing an initial run of 20 observations, the study team was able to determine the required sample size which is 80. This team only needed to perform 60 more observations to satisfy the requirements
True
GPS data can be used to determine the location, direction, and speed of a vehicle
True
Analysts use control delay most often because it is the easiest to measure and because the Highway Capacity Manual (HCM) (TRB, 2000) bases its defnition of intersection level of service on control delay, among other reasons
True
In AVI transponders, knowing the distance between booths will allow the calculation of overall travel speeds
True
Areas near the intersection corners should be clear of obstructions that may block the driver's view of conficting vehicles
True
In determining the saturation fow rate, observers must ignore vehicles joining the queue after the green signal appears
True
In determining the saturation fow rate, the observer cannot record a measurement if the queue is less than seven vehicles long when the signal turns green because short queues provide unstable data
True
It is the difference between the time a vehicle joins the rear of a queue and the time the vehicle clears the intersection
Time-in-queue
Cellular telephones can be used as a probe in a travel-time study with multiple approaches. Drivers can be recruited to use their cellular telephones to report their progression along a corridor relative co designated checkpoints
Cellular Telephone Probe Method
These are designed to measure speeds at specific locations under the traffic and environmental conditions prevailing at the time of the study
Spot speed studies
_______ of speed are made using permanent or handheld technology that apply the Doppler principle via, for example radar or laser measurement technology
Direct measurements
_______ of spot speeds calculate speed from time measurements of a vehicle traveling a known (short) distance, such as the distance between two closely spaced magnetic inductance loops
Indirect measurements
It is the average speed of all vehicles occupying a segment and is defined as the total distance traveled over the total travel time for all vehicles
Space mean speed
Analysts use this method when the purpose of the study requires or can be accommodated by measuring the spot speeds of all vehicles passing a point for a sample of time periods
All-vehicle sampling
It refers to the basic arithmetic mean of speed collected at a spot location
Time mean speed
_______ selection method may use a manual speed trap, but is generally carried out using the Doppler principle, direct measurement technique with radar, laser, or infrared technologies
Individual vehicle
If a researcher is trying to determine the 85th percentile speed of a highway, what is the minimum amount of spot speed samples needed?
30
K the constant for the confidence level needs a minimum of greater than ____ sample size to be valid
100
Two basic methods of data collection are direct and indirect measurements
False, Direct and Indirect -> Individual and All-vehicle
With the all-vehicle sampling method, obtaining an adequate sample is seldom a problem because deployments are usually made for at least a 15-minute period
False, 15 minutes -> 24 hours
Analysts use the all-vehicle selection method when the study purpose can be satisfied with a relatively small sample of spot speeds taken over relatively short time periods
False, All-vehicle -> Individual vehicle
The ratio of usable to total for all-vehicle sampling should not exceed 0.75. If this criterion is not met, the team should collect data during another period
False, not exceed -> exceed
Spot speed data are collected by one of two general approaches: direct and indirect
True
At in-road installations for all-vehicle sampling, it is advisable to check the functions and accuracy of the equipment at least once during every 24-hour data collection period
True
There are two types of average speed measures that express the rate of movement or speed of a vehicle
True
Successful spot speed studies using automatic data collection equipment depend on the operational reliability of the sensors and recorders, the physical installation of the sensors and lead wiring and the calibration and quality control measures employed
True