Transportation Networks. Optimality. Cost Functions. Deterministic User Equilibrium Assignment. Stochastic User Equilibrium Assignment. Trip Table Estimation. Network Reliability. Network Design. Conclusions. References. Index.

Transportation network analysis

This paper presents an overview of singular perturbations and time scales (SPaTS) in control theory and applications during the period 1984-2001 (the last such overviews were provided by [231, 371]). Due to the limitations on space, this is in way intended to be an exhaustive survey on the topic.

Singular perturbations and time scales in control theory and applications: An overview

IEEE International Conference on Robotics and Automation

Urban air quality is generally poor at traffic intersections due to variations in vehicles’ speeds as they approach and leave This paper examines the effect of traffic, vehicle and road characteristics on vehicular emissions with a view to understand a link between emissions and the most likely influencing and measurable characteristics It demonstrates the relationships of traffic, vehicle and intersection characteristics with vehicular exhaust emissions and reviews the traffic flow and emission models Most studies have found that vehicular exhaust emissions near traffic intersections are largely dependent on fleet speed, deceleration speed, queuing time in idle mode with a red signal time, acceleration speed, queue length, traffic-flow rate and ambient conditions The vehicular composition also affects emissions These parameters can be quantified and incorporated into the emission models There is no validated methodology to quantify some non-measurable parameters such as driving behaviour, pedestrian activity, and road conditions

Evaluating effects of traffic and vehicle characteristics on vehicular emissions near traffic intersections

An urban network of signalized intersections can be suitably modeled as a hybrid system, in which the vehicle flow behavior is described by means of a time-driven model and the traffic light dynamics are represented by a discrete event model. In this paper, a model of such a network via hybrid Petri nets is used to state and solve the problem of coordinating several traffic lights with the aim of improving the performance of some classes of special vehicles, i.e., public and emergency vehicles. The proposed model has been validated using real traffic data relevant to the city of Torino, Italy. Some relevant experimental results are reported and discussed.

Urban traffic control structure based on hybrid Petri nets

Continuous and timed Petri nets for the macroscopic and microscopic traffic flow modelling

This note studies a class of discrete-time nonlinear systems which depend on a small parameter. Using the singular perturbation theory in a systematic way, we give a trajectory approximation result based on the decomposition of the model into reduced and boundary layer models. This decomposition is used to analyze optimal control via maximum principle of such systems. As a result, significant order reduction of optimal control problems is achieved.

Optimal control of a particular class of singularly perturbed nonlinear discrete-time systems

The traffic flow theory is concerned with finding a relation among the variables of traffic flow. We propose a new approach which consists of representing these variables by those of continuous Petri nets with variable speed (VCPN). A model of VCPN is suggested for the analysis and control design in urban and interurban networks. The proposed model provides representation for both motorway corridors and complex road junctions.

Continuous Petri nets models for the analysis of traffic urban networks

Petri nets (PNs) are useful tools for the modeling and analysis of discrete event systems. This work deals with the estimation of firing and enabling sequences for timed transition PNs with unknown time delays. The marking and reserved marking of the places are measured online. The estimation problem has exact and approximated solutions that are described. Sufficient conditions are given on the measurement accuracy of the marking and reserved marking vectors, so that the estimation of firing and enabling sequences is an exact one. If the estimation provides several solutions, the PN is extended in order to give a unique solution. Numerical aspects of the estimation are also investigated. As a consequence of this, the proposed method provides interesting tools for the modeling, performance analysis, and above all the monitoring of manufacturing systems and road traffic networks.

A. El Moudni

Papers

Continuous and timed Petri nets for the macroscopic and microscopic traffic flow modelling

Optimal control of a particular class of singularly perturbed nonlinear discrete-time systems

Continuous Petri nets models for the analysis of traffic urban networks

Firing and enabling sequences estimation for timed Petri nets

Reliability analysis of a mechanical contact between deformable solids