Long-Range Dependence of Traffic Flow and Speed of a Motorway: Dynamics and Correlation with Historical Incidents
| Autor: | Sai Chand, Gregory Aouad, Vinayak Dixit |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
050210 logistics & transportation
Meteorology Mechanical Engineering 05 social sciences 010501 environmental sciences Traffic flow 01 natural sciences Correlation Fractal Flow (mathematics) Traffic congestion 0502 economics and business Range (statistics) Environmental science Time series Predictability Simulation 0105 earth and related environmental sciences Civil and Structural Engineering |
| Zdroj: | Transportation Research Record: Journal of the Transportation Research Board. 2616:49-57 |
| ISSN: | 2169-4052 0361-1981 |
| DOI: | 10.3141/2616-06 |
| Popis: | Speed and flow of vehicles tend to have several effects on the dynamics of a transport system. Fluctuations of these variables can implicate congestion, can lower predictability, and may even catalyze crashes. A concept of fractal theory called the Hurst exponent—a measure of the long-range dependence (LRD) of a time series—was used to understand the fluctuations in flow and speed of a motorway in Sydney, Australia. The spatial and temporal variation of the LRD for flow ( Hflow) and speed ( Hspeed) at several monitor sites is discussed. Furthermore, the effects of number of lanes on flow and speed predictability are explored. It was observed that the flow predictability of two-lane sections was significantly lower when compared with three-lane and four-lane sections. Conversely, the speed predictability of four-lane sections was considerably higher than that of two-lane and three-lane sections. Finally, traffic congestion was defined with regard to the LRD of speed, and its correlation with historical incident rates was measured. It was ascertained that monitor sites with a historically high proportion of large Hspeedwere correlated with unsafe locations. This study could lead to many applications of fractal analysis on highways and urban traffic. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|