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This paper addresses the general time-route assignment problem : One considers an air transportation network in a 2 dimensional space with asymmetric non-separable link cost and a fleet of aircraft with their associated route and slot of departure. For each flight a set of alternative routes and a set of possible slots of departure are defined. One must find "optimal" route and slot allocation for each aircraft in a way that significaly reduces the peak of workload in the most congested sectors and in the most congested airports, during one day of traffic. A state of the art of

Transportation researchers have long struggled to find satisfactory ways of describing and analysing traffic congestion, as evident from the large number of often competing approaches and models that have been developed. This paper aims to provide a review of the literature on this topic. The paper starts with the modelling of homogeneous traffic flow and congestion on an isolated road under stationary conditions. We set up the supply-demand framework used to characterize equilibrium and optimal travel volumes. Next, an overview of macroscopic and microscopic models of nonstationary traffic flow is given. We then describe how trip timing can be modelled, and discuss the essence of dynamic equilibrium. The paper next reviews the principles of static and dynamic equilibrium on a road network in a deterministic environment, and then identifies equilibrium concepts that account for stochasticity in demand and capacity. Finally, conceptual and practical issues regarding congestion pricing and investment on a network will be addressed.

Abstract. This article describes the impact and influence of the book, Studies in the Economics of Transportation, by M. Beckmann, C.B. McGuire and C.B. Winsten, published in 1956 by Yale University Press. Our focus is on the book’s impacts on innovations in modeling, methodological developments and applications in transportation, regional science and other disciplines, which continue to this day. JEL classification: R41, C6, N01 Key words: Traffic network equilibrium, history of regional science

This paper is concerned with the existence of solutions to a dynamic network equilibrium problem modelled as an infinite dimensional variational inequality. Our results are based on properties of operators that map path flow departure rates to consistent time-dependent path flows and other link performance functions. The existence result requires the introduction of a novel concept that strengthens the familiar concept of FIFO (`First-In-First-Out'). Following Ben-Akiva [3], one can identify four main elements in any dynamic network equilibrium model (DNEP): arc performance functions, path choice criterion, a demand model, flow conservation relationships at the nodes of the network. According to this author, the extension of a static to a dynamic setting requires the determination of time-dependent arc performance functions, temporal origin-destination demand, and the assessment of queueing effects on time-varying arrival rates. In general, these relationships are not available in clos...

Urban travel demand forecasting and traffic assignment models are important tools in developing transportation plans for a metropolitan area. These tools provide forecasts of urban travel patterns under various transportation supply conditions. The predicted travel patterns then provide useful information in planning the transportation system. Traffic assignment is the assignment of origin-destination flows to transportation routes, based on factors that affect route choice. The urban travel demand models, developed in the mid 1950s, provided accurate and precise answers to the planning and policy issues being addressed at that time, which mainly revolved around expansion of the highway system to meet the rapidly growing travel demand. However, the urban transportation planning and analysis have undergone changes over the years, while the structure of the travel demand models has remained largely unchanged except for the introduction of disaggregate choice models beginning in the mid-1970s. Legislative and analytical requirements that exceed the capabilities of these models and methodologies have driven new technical approaches such as

This paper considers a mass transit system in a regional area. The problem of improving the quality of the service in terms of costs perceived by the passenger is studied. A model to improve the effectiveness of the system maintaining the feasibility of the traffic assignment is proposed, along with new definitions of passenger assignment to support the proposed model. 1. Introduction In this paper we will consider a mass transit system in a regional area where both road and rail transportation may be used by commuters. Unlike the urban case [10], in a regional mass transit system, line frequencies are relatively low and trips can be considered as singular entities. We will assume that all the trips run on time according to a given time-table which is known by users; in addition, the vehicles have a fixed capacity (number of seats) which cannot be exceeded. Often transit companies have to cope with the problem of improving the level of service perceived by the users without increasing...

Morning commuters adjust their departure times in response to day-to-day changes in congestion. Advanced Traveler Information Systems (ATIS) may enable motorists to employ fundamentally new strategies when adapting their departure times to fluctuations in congestion. At the same time, new driver strategies will likely give rise to different road network behaviors. This paper explores the mutual feedback between driver strategy and traffic system performance through a simulation model of rush hour commuting. Motorists in this model choose departure times according to three adaptive strategies. When commuters apply adaptive strategies that require ATIS in the present model, outcomes for both individual motorists and the system as a whole are by several measures worse than when drivers use a simple strategy that does not require ATIS. These results largely agree with an earlier study of a nearly identical model of rush-hour commuting. This document is available in HTML on the ...

This report describes the methodologies and procedures developed through a contract to the University of Texas at Austin, in collaboration with the University of Maryland, to address these essential needs. Specifically, a simulation-assignment methodology has been developed to describe user's path choices in the network in response to real-time information, and the resulting flow patterns that propagate through the network, yielding information about overall quality of service and effectiveness, as well as localized information pointing to problem spots and opportunities for improvement. This methodology is intended for use off-line for evaluation purposes, or on-line for prediction purpose in support of advanced traffic management functions. In additional, algorithmic procedures have been developed to determine the best paths to which users should be directed so as to optimize overall system performance. Powerful extension

This paper describes the impact and influence of the book, Studies in the Economics of Transportation, by M. J. Beckmann, C. B. McGuire, and C. B. Winsten, published in 1956 by Yale University Press. The focus of this paper is on the book’s impacts on innovations in modeling, methodological developments, and applications in transportation science and in other disciplines as well.