9 million bicycles, but what about the cars in Beijing?

Mar 27, 2012

Forget the fact of there being "9 million bicycles in Beijing, that's not a fact. Indeed, motor vehicle traffic is fast becoming a big problem that has led to unsustainable pollution and draconian rules in some parts of the city. Now, Nan Ji of the Hebei United University in China and colleagues have developed an algorithm to help traffic planners optimize the flow of traffic across roundabouts.

Writing in the International Journal of Innovative Computing and Applications, Ji and colleagues at the Tangshan Tanggang Expressway Management Office and Tian Jin Polytechnic University explain how their models flow and figures out the largest traffic capacity through. The approach can compare the effects of using traffic signals in different modes or having such traffic controls disabled altogether. The system can also apply diversionary tactics to allow traffic to be channeled away from a particular roundabout at heavily congested times if possible.

In most cities, chronic and gridlock impede the flow of vehicles, wasting drivers' times and costing billions of dollars directly and indirectly as well as generating a sooty and smoggy carbon tracks across many. The roundabout was first posited as a way to smooth at the beginning of the twentieth century when there were many orders of magnitude fewer vehicles on the roads. Nevertheless, roundabouts with traffic signals to further control and prioritize traffic are being seen as the better option to conventional "crossroads" type intersections between stretches of road.

The team has considered three critical points in order to find a way to optimize roundabout implementation. They have looked at how to judge what controls might be needed with respect to traffic volume. They have looked at how delays at each entry and exit point on a roundabout might be balanced for the smoothest flow. They have also looked at how controlled flow compares with roundabouts with no traffic signals.

In testing the algorithm on a simulated roundabout in Beijing, and ignoring any number of bicycles, the team has found that they can reduce delays to just 11 seconds at the roundabouts' entry point with judicious timing of traffic signals.

Explore further: Coping with floods—of water and data

More information: "Mathematical model for designing the traffic circle control" in Int. J. Innovative Computing and Applications, 2012, 4, 58-66.

add to favorites email to friend print save as pdf

Related Stories

Organic traffic lights

Jun 30, 2009

Controlling road traffic in congested areas is difficult to say the least, a point to which any drive-time urban commuter might testify. An organic approach to traffic lights, might help solve the problem and avoid traffic ...

Dynamic toll for smooth-flowing traffic

Aug 12, 2011

Highway traffic can flow more freely thanks to a dynamic toll. Siemens has developed a special algorithm for traffic control systems that adjusts the toll charge to the current traffic situation. In return, ...

Smart traffic lights reduce fuel usage and lower emissions

Oct 27, 2010

(PhysOrg.com) -- Denso Corp. has designed the next version of 'the smart traffic light system'. By using messaging between vehicles and the traffic-light controller, better decisions about when to change signaling ...

Recommended for you

Coping with floods—of water and data

21 hours ago

Halloween 2013 brought real terror to an Austin, Texas, neighborhood, when a flash flood killed four residents and damaged roughly 1,200 homes. Following torrential rains, Onion Creek swept over its banks and inundated the ...

Cloud computing helps make sense of cloud forests

Dec 17, 2014

The forests that surround Campos do Jordao are among the foggiest places on Earth. With a canopy shrouded in mist much of time, these are the renowned cloud forests of the Brazilian state of São Paulo. It is here that researchers ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.