Transportation's Role in Reducing U.S. Greenhouse Gas Emissions ...

Transportation’s Role in Reducing U.S. Greenhouse Gas Emissions: Volume 2
Figure 4.1 Example MPG/Speed Relationship for Light-Duty Gasoline
Vehicles
Fuel Economy (mpg)
35
30
25
20
15
10
5
0
5 10 15 20 25 30 35 40 45 50 55 60 65 70 75
Speed (mph)
Source: http://www.fueleconomy.gov.
Traffic management strategies include:
• Signal optimization and coordination (retiming signals to reduce intersection delay,
and coordinating control of traffic signals along a corridor or network);
• Adaptive signal control (use of advanced software that continuously updates signal
timing based on demand);
• Incident management (identifying incidents more quickly, improving response times,
and managing incident scenes more effectively);
• Ramp metering (placing a stoplight on freeway on-ramps to “meter” or space out
traffic during periods of high demand);
• Integrated corridor management (coordination among multiple strategies);
• Active traffic management (emerging strategies to squeeze extra capacity out of the
system and prevent flow breakdown, such as lane control, speed harmonization, and
queue warning); and
• Vehicle Infrastructure Integration (providing a communications link between vehicles
on the road and roadside infrastructure, to provide for safer and more efficient
operations).
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