EVALUATION OF AN ALGORITHM FOR DETECTING URBAN FREEWAY INCIDENTS DURING LOW-VOLUME CONDITIONS

A computer program to detect vehicular incidents that occur on urban freeways during low-volume conditions was developed, tested, and evaluated. The type of incidents to be detected were those that involved vehicles that entered a freeway but, for some reason, did not pass through a defined study section. The algorithm can operate in real time and is based on an individual-vehicle input-output process. It was tested on traffic data from a four-lane section of freeway in Houston, Texas. The algorithm's performance was evaluated over a wide range of traffic volumes (100-1200 vehicles/h) and three different detector spacings--152.4, 304.8, and 457.2 m (500, 1000, and 1500 ft). In the 152.4-m section, the algorithm detected 65 percent (11/17) of the incidents that occurred. In the 304.8-m section, it detected 78 percent (14/18) of the incidents that occurred and, in the 457.2-m section, it detected 49 percent (17/35) of the incidents that occurred. Numerous lane changes and a bad detector at the first detection station caused the relatively poor performance of the algorithm in both the 152.4-m and the 457.2-m sections. The algorithm detected all incidents that occurred when the volume level was less than 400 vehicles/h. It detected 61 percent (37/61) of the incidents that occurred when the volume level was between 800 and 1200 vehicles/h. (Authors)

• Digital Copy:
  • Purchase a digital copy of this publication for $25 USD
• Summary URL:
  http://scholar.google.com/scholar_lookup?title=EVALUATION+OF+AN+ALGORITHM+FOR+DETECTING+URBAN+FREEWAY+INCIDENTS+DURING+LOW-VOLUME+CONDITIONS&author=D.+Fambro&author=G.+Ritch&publication_year=1980
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/03611981
• Supplemental Notes:
  • Publication of this paper sponsored by Committee on Freeway Operations.
• Authors:
  • Fambro, Daniel B
  • Ritch, Gene P
• Publication Date: 1980

Media Info

• Media Type: Print
• Features: Figures; Maps; Photos; References; Tables;
• Pagination: pp 31-39
• Monograph Title: Grade crossings, devices, visibility and freeway operations
• Serial:
  • Transportation Research Record
  • Issue Number: 773
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Algorithms; Detection and identification; Detectors; Freeways; Spacing; Traffic crashes; Traffic incidents; Traffic volume; Urban highways; Vehicle detectors
• Uncontrolled Terms: Incidents
• Old TRIS Terms: Freeway traffic accidents
• Subject Areas: Highways; Operations and Traffic Management; I73: Traffic Control;

Filing Info

• Accession Number: 00334174
• Record Type: Publication
• ISBN: 0309031176
• Files: TRIS, TRB
• Created Date: Oct 28 1981 12:00AM