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
A traffic engineer notices that vehicle queues from one intersection are blocking the stop bar of an upstream intersection. This condition is called:
Answer: Spillback
Spillback occurs when downstream congestion causes queues to extend back and block upstream intersections, disrupting signal coordination.
What is the purpose of an 'all-red' clearance interval at a traffic signal?
Answer: Provide time for vehicles and pedestrians to clear the intersection before conflicting movements begin
The all-red interval holds all approaches on red simultaneously, providing a safety buffer for vehicles that entered on late yellow to clear before cross traffic receives green.
In ITS, a 'Video Incident Detection' (VID) system is designed to:
Answer: Automatically identify incidents such as stopped vehicles or wrong-way drivers using camera feeds
VID algorithms analyze CCTV feeds to detect anomalies like stalled vehicles, debris, or wrong-way driving and alert operators.
Which federal manual establishes uniform standards for traffic control devices including signs, signals, and pavement markings in the United States?
Answer: Manual on Uniform Traffic Control Devices (MUTCD)
The MUTCD, published by FHWA, is the national standard governing the design, placement, and operation of all traffic control devices on public roads.
What is 'traffic signal coordination' intended to achieve on an arterial?
Answer: Create a 'green wave' so vehicles can travel through multiple signals without stopping
Coordination offsets green phases along a corridor so a platoon of vehicles traveling at the design speed encounters mostly green lights.
When a signal controller operates in 'free' mode, it means:
Answer: The controller is running its own timing without synchronization to adjacent signals
Free mode means the controller operates independently on its local clock without a coordination reference signal, breaking the green wave.
Transit Signal Priority (TSP) differs from emergency vehicle preemption in that TSP:
Answer: Makes minor adjustments like extending green or advancing the next green to help buses stay on schedule
TSP makes conditional, non-disruptive adjustments to help transit vehicles without fully preempting normal signal operation.