Comparison of decentralized and centralized signal control methods on a large-scale urban networkComparison of decentralized and centralized signal control methods on a large-scale urban network Μεταπτυχιακή Διατριβή Master Thesis 2016-07-122016enNowadays, the rapid increase of the number of vehicles has turned the traffic congestion to a frequent occurrence in urban areas and, as the construction of new infrastructure is usually not possible, there is a great need to exploit the existing infrastructure through a more efficient management of the traffic flow. Signal control includes a variety of methods and has been considered as one of the major means to respond to this challenge.Traditionally, centralized control strategies, developed based upon more or less complex traffic flow models, have been considered as the most appropriate approach towards traffic flow management and control in urban areas. Recently, however, a shift is observed towards the development of approaches, which, based on a decentralized and model-free logic, are expected to improve the traffic flow efficiency at network level, with a minimum design effort and infrastructure investment. It is the aim of this thesis to present, study, and compare two innovative decentralized approaches proposed in the relevant literature. The first, which is the basis of the SURTRAC traffic control system, considers the signal control as a job scheduling problem, while the second which is known as the max or back pressure algorithm, considers the signal control problem as a resource allocation problem. The thesis aims also at comparing the effectiveness and performance of these decentralized approaches against a well-established centralized strategy, the TUC (Traffic-responsive Urban Control) strategy, which has been developed so as to provide coordinated traffic responsive control in large-scale urban networks. For the purpose of the investigations, the simulation model of a part of the urban network of Chania, Greece, is used under several scenarios of demand. Summarized conclusions are finally given, on the strengths and weaknesses of each approach, together with some directions for future research.http://creativecommons.org/licenses/by/4.0/Πολυτεχνείο Κρήτης::Σχολή Μηχανικών Παραγωγής και ΔιοίκησηςPappa_Theodora_Dip_2016.pdfChania [Greece]Library of TUC2016-07-12application/pdf1.5 MBfree Pappa Theodora Παππα Θεοδωρα Papamichail Ioannis Παπαμιχαηλ Ιωαννης Papageorgiou Markos Παπαγεωργιου Μαρκος Nikolos Ioannis Νικολος Ιωαννης Πολυτεχνείο Κρήτης Technical University of Crete Urban networks