Dresden 2006 – scientific programme
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AKSOE: Physik sozio-ökonomischer Systeme
AKSOE 9: Traffic Dynamics, Urban and Regional Systems
AKSOE 9.2: Talk
Wednesday, March 29, 2006, 14:30–15:00, BAR 205
Scaling Laws in the Spatial Structure of Urban Road Networks — •Stefan Lämmer — Technische Universität Dresden
The urban road networks of the 20 largest German cities have been analysed, based on a detailed database providing the geographical positions as well as the travel-times for network sizes up to 37,000 nodes and 87,000 links. As the human driver recognises travel-times rather than distances, faster roads appear to be ‘shorter’ than slower ones. The resulting metric space has an effective dimension d>2, which is a significant measure of the heterogeneity of road speeds. We found that traffic strongly concentrates on only a small fraction of the roads. The distribution of vehicular flows over the roads obeys a power-law, indicating a clear hierarchical order of the roads. Studying the cellular structure of the areas enclosed by the roads, the distribution of cell sizes is scale invariant as well.