Gradient Projection Method for Simulation-Based Dynamic Traffic Assignment

A gradient projection method is presented to solve the problem with dynamic traffic assignment. The gradient projection scheme is a feasible direction algorithm that operates directly in the space of path flows. The algorithm was applied to a simulation-based model for dynamic traffic assignment tha...

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Published inTransportation research record Vol. 2284; no. 1; pp. 70 - 80
Main Authors Yang, Inchul, Jayakrishnan, R.
Format Journal Article
LanguageEnglish
Published Los Angeles, CA SAGE Publications 01.01.2012
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ISSN0361-1981
2169-4052
DOI10.3141/2284-09

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Abstract A gradient projection method is presented to solve the problem with dynamic traffic assignment. The gradient projection scheme is a feasible direction algorithm that operates directly in the space of path flows. The algorithm was applied to a simulation-based model for dynamic traffic assignment that used microscopic simulation for supply-side modeling. The formulation used link cost functions that were separate for moving and queuing vehicles on each link, so that the formulation could effectively capture the effects of traffic dynamic characteristics on each group, especially in arterial networks. The model and solution algorithm were applied to a small real-world network, and the performance was studied. The gradient projection algorithm avoided the problem of convergence to nonoptimal conditions shown by the prevalent method of successive averages and demonstrated significantly faster convergence.
AbstractList A gradient projection method is presented to solve the problem with dynamic traffic assignment. The gradient projection scheme is a feasible direction algorithm that operates directly in the space of path flows. The algorithm was applied to a simulation-based model for dynamic traffic assignment that used microscopic simulation for supply-side modeling. The formulation used link cost functions that were separate for moving and queuing vehicles on each link, so that the formulation could effectively capture the effects of traffic dynamic characteristics on each group, especially in arterial networks. The model and solution algorithm were applied to a small real-world network, and the performance was studied. The gradient projection algorithm avoided the problem of convergence to nonoptimal conditions shown by the prevalent method of successive averages and demonstrated significantly faster convergence.
Author Yang, Inchul
Jayakrishnan, R.
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Snippet A gradient projection method is presented to solve the problem with dynamic traffic assignment. The gradient projection scheme is a feasible direction...
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SubjectTerms Algorithms
Computer simulation
Convergence
Dynamics
Mathematical models
Projection
Traffic engineering
Traffic flow
Title Gradient Projection Method for Simulation-Based Dynamic Traffic Assignment
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