Results 181-186 of 186.
Bookmark and Share    
Full Text
Peer Reviewed
See detailEvaluating the effects of information reliability on travellers’ route choice
Bifulco, Gennaro N.; Di Pace, Roberta; Viti, Francesco UL

in European Transport Research Review (2013)

Purpose This paper analyses travellers’ behaviour with respect to route choice in a context where an Advanced Traveller Information System (ATIS) is in place. ATIS are important applications in the field ... [more ▼]

Purpose This paper analyses travellers’ behaviour with respect to route choice in a context where an Advanced Traveller Information System (ATIS) is in place. ATIS are important applications in the field of intelligent transportation systems (ITS). However, the practical impact of ATIS is still a matter for debate, and identification of expected route choice behaviour under ATIS is one of themain ways to assess their practical importance. Methods Travellers’ choices are frequently explored by means of stated preference (SP) approaches. In this paper we discuss some issues to be addressed when an SP survey is carried out, with particular reference to cases where a repeated choice approach is employed in the survey. Results Our analysis concerns an application of the SP approach in a pilot study aimed at identifying the effects of ATIS accuracy on travellers’ compliance with information. Conclusions This paper aims tomake two major contributions. First of all, empirical analyses based on proper indicators and statistical tests are suggested in order to evaluate how the collected data have to be handled in order to eliminate transient route-choice observations. These are due to the warm-up phase inherently associated with the survey method adopted, dealing with repeated choices. Secondly, we analyse (stationary) route choice in order to assess the effects of information reliability (and the kind of information) on both route choice and compliance. [less ▲]

Detailed reference viewed: 152 (6 UL)
Full Text
Peer Reviewed
See detailEquilibrium in capacitated network models with queueing delays, queue-storage, blocking back and control
Smith, Mike J.; Huang, Wei; Viti, Francesco UL

in Procedia Social and Behavioral Sciences (2013), 80

This paper considers a steady-state, link-based, fixed (or inelastic) demand equilibrium model with explicit link-exit capacities, explicit bottleneck or queuing delays and explicit bounds on queue ... [more ▼]

This paper considers a steady-state, link-based, fixed (or inelastic) demand equilibrium model with explicit link-exit capacities, explicit bottleneck or queuing delays and explicit bounds on queue storage capacities. The (spatial queueing) model at the heart of this equilibrium model takes account of the space taken up by queues both when there is no blocking back and also when there is blocking back. The paper shows in theorem 1 that a feasible traffic assignment model has an equilibrium solution provided prices are used to impose capacity restrictions and utilises this result to show that there is an equilibrium with the spatial queueing model, provided queue-storage capacities are sufficiently large. Other results are obtained by changing the variables and sets in theorem 1 suitably. These results include: (1) existence of equilibrium results (in both a steady state and a dynamic context) which allow signal green-times to respond to prices and (2) an existence of equilibrium result which allow signal green-times to respond to spatial queues; provided this response follows the P0 control policy in Smith (1979, 1987). These results show that under certain conditions the P0 control policy maximises network capacity. The spatial queueing model is illustrated on a simple network. Finally the paper includes elastic demand; this is necessary for long-run evaluations. Each of the steady state models here may be thought of as a stationary solution to the dynamic assignment problem either with or without blocking back. [less ▲]

Detailed reference viewed: 200 (4 UL)
Full Text
See detailSignal control strategies in day-to-day dynamic process of combined traffic assignment and control
Huang, Wei; Viti, Francesco UL; Tampere, Chris M.J.

Scientific Conference (2013)

Detailed reference viewed: 95 (3 UL)
Full Text
Peer Reviewed
See detailAn Iterative Learning Approach for Signal Control in Urban Traffic Networks
Huang, Wei; Viti, Francesco UL; Tampere, Chris M.J.

in Proceedings of IEEE-ITS Conference (2013)

Traffic signal control influences route choice in traffic networks, and may even determine whether a traffic system settles in equilibrium or destabilizes into oscillatory patterns. Ideally, a stable ... [more ▼]

Traffic signal control influences route choice in traffic networks, and may even determine whether a traffic system settles in equilibrium or destabilizes into oscillatory patterns. Ideally, a stable equilibrium flow pattern should result from the interaction between control and route choice on a long-term horizon. This paper proposes an iterative learning approach for designing signal controls able to attract the system to equilibrium in an acceptable convergence speed. The traffic assignment model and combined traffic assignment and control problem are first introduced. An iterative learning control (ILC) based signal control is formulated and a basic model inversion method is analyzed. To deal with the nonlinearity of traffic system, a Newton based ILC algorithm is applied. Test in an example network verifies the effectiveness of the ILC method in achieving stable equilibrium in the traffic system. [less ▲]

Detailed reference viewed: 141 (0 UL)
Full Text
Peer Reviewed
See detailDynamic modeling of VISSIM critical gap parameter at unsignalized intersections
Viti, Francesco UL; Wolput, Bart; Tampere, Chris M.J. et al

Poster (2013)

Detailed reference viewed: 84 (0 UL)
Full Text
Peer Reviewed
See detailCalibration of a microscopic simulation model for emission calculation
Li, Jie; Van Zuylen, Henk J.; Chen, Yusen et al

in Transportation Research. Part C : Emerging Technologies (2013), 31

Emissions by road traffic can be reduced by optimising traffic control. The impact of this optimisation on emission can be analysed ex ante by simulation. The simulation programs used for this analysis ... [more ▼]

Emissions by road traffic can be reduced by optimising traffic control. The impact of this optimisation on emission can be analysed ex ante by simulation. The simulation programs used for this analysis should be valid with respect to the traffic characteristics that determine the emissions. Thus calibration of the parameters is a prerequisite. In most cases, volumes, travel times and queues are used to calibrate simulation models, rather than detailed driving characteristics such as speed and acceleration patterns. However, these driving behaviour parameters determine the vehicular emissions to a great extent. A study was carried out in which the driving behaviour parameters in a microscopic simulation model (VISSIM) were calibrated using real trajectories collected by image processing at an intersection in Rotterdam. The sensitivity of the simulation results for driving behaviour parameters was investigated. The most influential parameters were identified and adjusted to ensure that the simulation results were consistent with the observed traffic and could provide valid estimations of the total production of emissions. [less ▲]

Detailed reference viewed: 140 (6 UL)