A NOTE ON THE INTERPRETATION OF THE DUAL VARIABLES IN ESTIMATING TRAFFIC CAPACITY AT SIGNAL-CONTROLLED ROAD JUNCTIONS

The values of the dual variables in a constrained optimisation problem can be used to estimate the sensitivity of the optimal value of the objective function to changes in the constraints. Allsop (1972) used standard methods of linear programming to derive expressions for the sensitivity of the reserve capacity at a signal-controlled junction to various changes in the traffic engineering constraints. That analysis used the assumption that the maximum reserve capacity would be achieved when the cycle time used is maximal. While this normally occurs, some junctions have come to light where a reduction in the cycle time increases the capacity. Allsop's analysis is extended here to account for this possibility. (Author/TRRL)

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/01912615
• Corporate Authors:

  Pergamon Press, Incorporated

  Headington Hill Hall
  Oxford OX30BW,    
• Authors:
  • Heydecker, B G
• Publication Date: 1983-10

Media Info

• Features: References;
• Pagination: p. 359-364
• Serial:
  • Transportation Research Part B: Methodological
  • Volume: 17B
  • Issue Number: 5
  • Publisher: Elsevier
  • ISSN: 0191-2615
  • Serial URL: http://www.sciencedirect.com/science/journal/01912615

Subject/Index Terms

• TRT Terms: Constraints; Estimating; Highway capacity; Intersections; Linear programming; Mathematical analysis; Maximization; Optimization; Sensitivity; Signalized intersections; Traffic engineering; Traffic signal cycle; Traffic signals; Variables
• Uncontrolled Terms: Change; Maximum; Modifications; Optimum
• ITRD Terms: 6471: Analysis (math); 643: Capacity (road, footway); 576: Cycle (traffic signals); 455: Junction; 9042: Maximum; 9048: Modification; 655: Traffic engineering; 565: Traffic signal
• Subject Areas: Highways; Operations and Traffic Management; I71: Traffic Theory; I73: Traffic Control;

Filing Info

• Accession Number: 00382714
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD, TRIS
• Created Date: Apr 30 1984 12:00AM