CHICAGO, Nov. 17 (Xinhua) -- By capturing the different routes by which vehicles can travel between locations, researchers at the University of Illinois (UI) have developed a new computer algorithm that helps quantify regions of congestion in urban areas and suggests ways around them.
The researchers approached the issue by designing a computer algorithm to capture the topology - or relationship between the different routes between locations - of road networks.
"We found that the most significant traffic bottlenecks in Manhattan seem to arise as a result of the city's structural layout," said study co-author Daniel Carmody at UI. "For example, the fact that a bridge enters Manhattan at a latitude where traffic is already limited due to Central Park slows traffic in the area considerably."
The researchers performed a comparative analysis using traffic patterns in Chengdu, China, to test if the algorithm works equally well in areas with different layouts. Manhattan has a long and thin structure, while Chengdu is round. There are significant differences in the way traffic moves between these two different setups.
"The bottlenecks in Chengdu seem to arise due to the function of the buildings in a particular area," Carmody said. "For example, it is hard to travel in and out of the central business district in Chengdu because of the sheer volume of traffic alone. Beltways, or faster streets around congested areas, have emerged in circles around this area, which is not surprising because this feature was intentionally built into the city."
In Manhattan, the bridges and tunnels that form the entry and exit points cause traffic slowdowns. However, in lower Manhattan, where drivers seem to obey the lower posted speed limits, traffic moves more smoothly, forming a new traffic beltway with the southern end of Central Park acting as a barrier between lower and central Manhattan.
"It surprised us that there is an emergent beltway in such a congested area of Manhattan," Carmody said. "This indicates that, unlike in Chengdu, beltways seem to arise from driver behavior even when they aren't part of the structural plan of a traffic network."
The researchers envision this technology giving urban planners a means to quantify traffic patterns, leading to better mitigation.
The study, posted on UI's website on Tuesday, has been published in the Journal of Physics. Enditem
