Intelligent Control of Urban Road Networks: Algorithms, Systems and Communications

Research output: Chapter in Book/Report/Conference proceedingConference contribution


This paper considers control in road networks. Using a simple example based on the well-known Braess network [1] the paper shows that reducing delay for traffic, assuming that the traffic distribution is fixed, may increase delay when travellers change their travel choices in light of changes in control settings and hence delays. It is shown that a similar effect occurs within signal controlled networks. In this case the effect appears at first sight to be much stronger: the overall capacity of a network may be substantially reduced by utilising standard responsive signal control algorithms. In seeking to reduce delays for existing flows, these policies do not allow properly for consequent routeing changes by travellers. Control methods for signal-controlled networks that do take proper account of the reactions of users are suggested; these require further research, development, and careful real-life trials.
Original languageEnglish
Title of host publicationCommunications Infrastructure. Systems and Applications in Europe
Subtitle of host publicationProceedings of the First International ICST Conference, EuropeComm 2009, London, UK, August 2009
EditorsRashid Mehmood, Eduardo Cerqueira, Radoslaw Piesiewicz, Imrich Chlamtac
Number of pages12
ISBN (Electronic)978-3-642-11283-6
ISBN (Print)3-642-11283-8
Publication statusPublished - 2010

Publication series

NameLecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering

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