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Title:

AUTOMATIC FREEWAY SURVEILLANCE AND EVALUATION TECHNIQUES

Accession Number:

00225548

Record Type:

Component

Abstract:

A PILOT FREEWAY DETECTION SYSTEM WAS INSTALLED IN 1962, UNDER THE CHICAGO AREA EXPRESSWAY SURVEILLANCE PROJECT, WHICH HAS BEEN REFINED TO PROVIDE AUTOMATIC SURVEILLANCE, CONTROL, AND EVALUATION FOR A TOTAL OF 24 DIRECTIONAL MILES ON TWO CHICAGO AREA EXPRESSWAYS. CRITICAL SURVEILLANCE- EVALUATION DETECTORS TRANSMIT DATA OVER LEASED PHONE LINES TO A PROCESS-CONTROL COMPUTER IN THE PROJECT OFFICE. THE DIGITAL COMPUTER PROCESSES DETECTOR DATA INTO ON-LINE, REAL-TIME, FREEWAY SURVEILLANCE, ENTRANCE RAMP METERING CONTROL AND EVALUATION OUTPUTS. A DESCRIPTION IS GIVEN OF HOW THE ELECTRONIC SURVEILLANCE SYSTEM IS USED TO AUTOMATICALLY EVALUATE FREEWAY TRAFFIC OPERATIONS THROUGH EACH RUSH PERIOD. ON ONE AUTOMATIC TYPEWRITER, AN ON-LINE LANE OCCUPANCY PLOT IS DEVELOPED BY THE DIGITAL COMPUTER. ON THE SECOND AUTOMATIC TYPEWRITER, AN EXCESS VEHICLES PLOT IS DEVELOPED BY THE DIGITAL COMPUTER FROM A CLOSED SYSTEM OF FREEWAY AND RAMP DETECTORS. USING THE INPUT-OUTPUT TECHNIQUE OF COMPUTING SUBSYSTEM DENSITY CHANGES, THE EXCESS TOTAL TRAVEL TIME EXPERIENCED BY RUSH-PERIOD TRAFFIC IS DETERMINED. EXAMPLES ARE PRESENTED TO ILLUSTRATE THE EXTREMES OF RUSH PERIOD FREEWAY OPERATIONS, AS WELL AS ADDITIONAL REFINEMENTS IN THE PRINTOUT FORMAT.

Supplemental Notes:

Paper sponsored by Committee on Freeway Operations. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved

Monograph Accession #:

01410219

Report/Paper Numbers:

Paper No 1

Authors:

McDermott, Joseph M

Pagination:

p 158

Publication Date:

1969

Serial:

Highway Research Record

Issue Number: 279
Publisher: Highway Research Board

Media Type:

Print

Old TRIS Terms:

Subject Areas:

Highways; Operations and Traffic Management

Files:

TRIS, TRB

Created Date:

Oct 21 1994 12:00AM

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