Dynamic Traffic Assignment III: Distributed Schemes

TD11.1 A Cooperative Decentralized Architecture & A Communication Protocol for Dynamic Traffic Assignment Yaser Hawas, Hani S. Mahmassani --- Univ. of TX, Dept. of Civil Eng., ECJ 6.2, Austin, TX 78712 , (yhawas@mail.utexas.edu)

We describe a decentralized architecture that utilizes a set of¨ controllers for reactive route guidance. The control logic comprises¨ heuristics together with the breadth-first algorithm. Adjacent¨ controllers share information of the local traffic conditions in¨ their vicinity. A communication protocol is designed to control the¨ information sharing process.

TD11.2 A Common Object Request Broker Architecture-Based Distributed Dynamic Traffic Assignment System for Large-Scale Networks Steven Travis Waller, Athanasios Ziliaskopoulos --- Northwestern Univ., Dept. of Civil Eng., Evanston, IL 60202 ,

A large-scale design of a DTA model is implemented in the¨ inter-language unification package, a CORBA compliant object¨ oriented distributed system. CORBA handles all communication and¨ synchronization tasks for the system. The distribution of the¨ modules to processors (or processor clusters) is discussed along¨ with computational experience on a cluster of workstations.

TD11.3 ALLIANCE: A Decentralized Approach to System Optimal Routings in Dynamic Traffic Networks Alfredo Garcia, Daniel J. Reaume, Robert L. Smith --- Univ. of MI, Dept. of IOE, Ann Arbor, MI 48109 , (agarcia@engin.umich.edu)

We introduce a novel procedure to compute system-optimal routing in¨ a dynamic traffic network. Fictitious play is utilized within a game¨ of identical interests wherein vehicles are treated as players with¨ the common payoff of average trip time experienced. Conditions under¨ which convergence holds are presented as well as results from a¨ large-scale computational test on a real network.

TD11.4 An Integrated Architecture for Real-Time Dynamic Traffic Assignment Yaser Hawas, Hani S. Mahmassani --- Univ. of TX, Dept. of Civil Eng., ECJ 6.2, Austin, TX 78712 , (yhawas@mail.utexas.edu)

We describe various operational modes of the dynamic traffic¨ assignment system developed at the University of Texas at Austin,¨ including a centralized rolling horizon predictive mode for¨ multiple user classes for both descriptive and normative route¨ guidance as well as a decentralized reactive mode with local search¨ heuristics.