Intelligent Transportation Systems (ITS) Flashcards
6 cards from real CTE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Intelligent Transportation Systems (ITS) flashcards as text
What is 'travel time reliability' and why is it important in ITS performance measurement?
Answer: The consistency of travel times from day to day, reflecting predictability of the transportation system
Travel time reliability measures day-to-day variability in travel times; a reliable facility has consistent travel times that travelers can plan around, which FHWA measures using the Planning Time Index (PTI) and Buffer Index (BI).
What is 'ramp metering' and what transportation benefit does it provide?
Answer: Controlling the rate at which vehicles enter a freeway on-ramp using traffic signals, to maintain mainline traffic flow
Ramp metering uses a signal at freeway on-ramps to regulate vehicle entry rates, preventing traffic demand from exceeding freeway capacity and maintaining stable flow that prevents breakdown and reduces throughput loss.
What does 'connected vehicle' technology refer to in the context of ITS?
Answer: Vehicles equipped with wireless communication capabilities that exchange data with other vehicles, infrastructure, pedestrians, and the cloud
Connected vehicles use wireless communication (DSRC, C-V2X) to exchange data with other vehicles (V2V), infrastructure (V2I), pedestrians (V2P), and the network (V2N) to improve safety, mobility, and efficiency.
In freeway traffic flow theory, what is the 'capacity drop' phenomenon?
Answer: The observed drop in throughput when a freeway transitions from free flow to congested breakdown conditions
Capacity drop refers to the empirically observed phenomenon where throughput at a freeway bottleneck during congested conditions is 5–15% lower than the pre-breakdown discharge rate, sustained as long as congestion persists.
What is 'Wrong Way Driving (WWD) detection' and which ITS technology is most commonly used?
Answer: Detection of vehicles entering freeways in the wrong direction using radar, video, or thermal sensors at off-ramps, triggering alerts and DMS warnings
Wrong way driving detection systems use radar, thermal cameras, or video analytics at freeway off-ramps and interchange areas to detect wrong-way vehicle movements and immediately activate DMS, signals, and alert responders.
What is 'performance-based practical design' in the context of ITS project development?
Answer: Selecting ITS treatments and investments based on measured performance outcomes and data-driven needs rather than prescriptive standards
Performance-based practical design applies performance measurement to ITS investment decisions, selecting technologies and treatments that address identified deficiencies and deliver measured outcomes (reduced delay, improved reliability).