This article on Wired Blog talks of how various US states are attempting to use technology to track and unclog traffic congestion:
"We're already tracking all the buses all the time," said Daniel Dailey, an electrical engineering professor at the University of Washington who leads the arterial traffic project. "What's left is to differentiate when traffic is slowing the buses down."
The university's Intelligent Transportation Systems Research Program began collecting bus data close to seven years ago. The data feeds MyBus, a web and text-messaging service that notifies commuters about delays. Seattle-area bus commuters use the service about 5 million times a month, Dailey said"
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