Flow, Speed, Density, and Their Relationships

  • Lily Elefteriadou
Part of the Springer Optimization and Its Applications book series (SOIA, volume 84)


Flow, speed, and density are the three primary characteristics of traffic and are used to describe various aspects of operations of a highway facility. When describing and assessing traffic operations, we are often concerned with the movement of a group of vehicles, or the traffic stream as a whole, rather than the movement of each vehicle. In those cases, it is more convenient to describe traffic operations in terms of macroscopic measures of traffic.


Time Headway Traffic Stream Congested Condition Density Relationship Instantaneous Speed 
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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Lily Elefteriadou
    • 1
  1. 1.Department of Civil and Coastal EngineeringUniversity of FloridaGainesvilleUSA

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