Traffic Management & Control Systems Flashcards
7 cards from real NETTCP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Traffic Management & Control Systems flashcards as text
What is the function of a ramp meter on a freeway?
Answer: Regulate the rate at which vehicles enter the freeway to maintain mainline flow
Ramp meters use signals to release vehicles one or two per green cycle, preventing demand surges that cause mainline breakdown.
Which communication protocol is most commonly associated with traffic signal controllers in the United States for standardized communication?
Answer: NTCIP (National Transportation Communications for ITS Protocol)
NTCIP is the standard protocol suite allowing interoperability between traffic controllers, management systems, and field devices from different vendors.
In a traffic signal system, 'preemption' is activated by:
Answer: Emergency vehicles, trains, or transit priority requests
Preemption overrides normal signal operation to provide right-of-way to emergency vehicles, rail crossings, or high-priority transit.
The Highway Capacity Manual (HCM) defines Level of Service (LOS) 'F' as:
Answer: Oversaturated conditions with demand exceeding capacity and long delays
LOS F represents a breakdown of flow where demand exceeds capacity, causing queues to grow and delays to become unacceptable.
What does a flashing yellow arrow signal indicate to a left-turning driver?
Answer: Yield to oncoming traffic and pedestrians, then turn left when safe
A flashing yellow arrow is a permissive left-turn indication requiring drivers to yield before turning, replacing the traditional circular green for this movement.
In traffic engineering, 'v/c ratio' stands for:
Answer: Volume-to-capacity ratio
The volume-to-capacity ratio measures how close a roadway or intersection is to its operational limit; values near or above 1.0 indicate congestion.
Which device is used to detect pedestrian presence at a crosswalk and extend the walk phase if needed?
Answer: Push-button actuation with extended hold timer
Extended push-button actuators with hold timers detect when a pedestrian is still in the crosswalk and can extend the walk or pedestrian clearance interval.