Acronmyms
Definitions
Equations/Relationships
Intersections
Roads/Simulation
100
ITE
What is Institute of Transportation Engineers
100
The movement of passengers and goods from one place to another.
What is Transportation?
100
Density x Speed
What is Flow?
100
Another term for traffic circle at an intersection.
What is a Roundabout?
100
ITS
What are Intelligent Transportation Systems?
200
FHWA
What is the Federal Highway Administration?
200
Number of vehicles crossing a detector over a certain amount of time.
What is Flow?
200
Denoted as "R" in vertical/horizontal curves.
What is the Radius of a curve?
200
The total time for a signal to complete all phases.
What is the Cycle Length?
200
Expressway with fully controlled access & continuous flow.
What is a Freeway?
300
TRB
What is the Transportation Research Board?
300
A simulation model which represents aggregated vehicles in stream as opposed to modeling each vehicle individually.
What is a Macroscopic model?
300
Denoted as "PC" in horizontal curves.
What is the Point of Curve?
300
Signal timing where cycle length, green time, etc. are all fixed.
What is a Pre-timed Signal Control?
300
Denoted as "PT" in horizontal curves.
What is Point of Tangent?
400
OD (Matrix)
What is an Origin-Destination Matrix?
400
Adjustment for trucks/RV's in the flow equation.
What is the Heavy Vehicle Factor?
400
An additional 18.4 cents per gallon of gas.
What is the Gas Tax?
400
The portion of the cycle length that is not completely utilized due to starts/stops at the change of phases.
What is Lost Time?
400
Hourly volume / 4(max 15-min volume).
What is the Peak Hour Factor?
500
MPO
What is a Metropolitan Planning Organization?
500
When two movements join to form a single traffic stream.
What is a Merging movement?
500
Harmonic mean of individual speeds.
What is Space Mean Speed?
500
Part of a cycle which allows any combination of traffic movements receiving right-of-way during an interval
What is a Signal Phase?
500
If 100% of drivers are familiar the area we take this as 1.0
What is the Driver Adjustment Factor (fp)?
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