01152535

Component

Probe-based real-time traffic monitoring systems, such as Wireless Location Technology and probe car GPS-based systems, have become increasingly attractive as a cost-effective alternative to traditional loop-detector and other fixed detection technologies. In order to enhance traffic operations control room monitoring capabilities, however, probe-based systems must be capable of providing reliable link speed information during short-term non-free flow conditions such as traffic incidents and severe weather events. This paper describes a heuristic data enhancement algorithm that takes probe-based system measurements as input and generates a real-time output stream that provides a more accurate trace of ongoing event conditions. The data enhancement algorithm detects an unplanned event by seeking traffic speed measurements beyond the pre-defined speed threshold from a calculated reference speed. A variable event clearance window is then established by checking the number of low-speed event data points over the last two hours and the length of time from the start of the current event. Within the variable length event clearance window, the last trusted non-free flow traffic speed will be reported instead of un-trusted free flow system measurements. The enhanced measurements provide a more faithful representation of the continuous impact of the event when compared to ground truth data.

01147878

10-2909

English

20p

2010

Transportation Research Board 89th Annual Meeting

DVD

Figures (7) ; References (9) ; Tables (2)

Algorithms; Heuristic methods; Probes (Measuring devices); Real time information; Traffic data; Traffic flow; Traffic incidents; Traffic models; Traffic speed; Weather conditions; Wireless communication systems

Data and Information Technology; Highways; I71: Traffic Theory

Transportation Research Board Annual Meeting 2010 Paper #10-2909

BTRIS, TRIS, TRB

Jan 25 2010 11:25AM