Variance and Accuracy of the Sheared Queue Model

Understanding time-dependent queues is essential for reliable journey time prediction in periods involving transient over-saturation. Detailed mathematical and simulation methods are available but practical traffic modeling also requires computationally efficient models. The best know is the sheared queue model, obtained by transforming a deterministic time-dependent and a probabilistic steady-state equilibrium model, but this can be inaccurate in certain cases. The inaccuracy can be traced to the quasi-equilibrium formulation and incomplete information about the queue length probability distribution. A formula for the variance of queue length is derived and is used to both test and improve the accuracy of the queue model. Further improvement is potentially available by incorporating the initial utilization as well as the initial queue size and variance into the model.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/9780080450926
• Supplemental Notes:
  • Abstract reprinted with permission from Elsevier.
• Corporate Authors:

  Elsevier

  Linacre House, Jordan Hill
  Oxford,   United Kingdom  OX2 8DP
• Authors:
  • Taylor, Nicholas
• Conference:
  • 4th IMA International Conference on Mathematics in Transport
  • Location: London , United Kingdom
  • Date: 2005-9-7 to 2005-9-9
• Publication Date: 2007

Language

• English

Media Info

• Media Type: Print
• Edition: First
• Features: Figures; References;
• Pagination: pp 259-278
• Monograph Title: Mathematics in Transport. Selected Proceedings of the 4th IMA International Conference on Mathematics in Transport

Subject/Index Terms

• TRT Terms: Queuing; Time dependence; Traffic equilibrium; Traffic flow; Traffic oversaturation; Traffic queuing; Traffic simulation; Variance
• Uncontrolled Terms: Steady state (Traffic)
• Subject Areas: Highways; Operations and Traffic Management; Planning and Forecasting; I72: Traffic and Transport Planning; I73: Traffic Control;

Filing Info

• Accession Number: 01081131
• Record Type: Publication
• ISBN: 9780080450926
• Files: TRIS
• Created Date: Nov 26 2007 9:55AM