Urban Arterial Network Research Articles

Real-Time Traffic Volatility Forecasting in Urban Arterial Networks

A methodology is presented for forecasting traffic volatility in urban arterial networks with real-time traffic flow information. This methodology provides a generalization of the standard modeling approach, in which both the mean, modeled by an autoregressive moving average process, and the variance, modeled by an autoregressive conditional heteroscedastic process, are time-varying. The statistical analysis and forecasting performance of the proposed model are investigated with real-time traffic detector data from a real urban arterial network. The results indicate the potential of the proposed model to improve the accuracy of predicted traffic volatility across different lengths of forecasting horizon in comparison with the standard generalized autoregressive conditional heteroscedastic methodology.

Real-Time Traffic Volatility Forecasting in Urban Arterial Networks

A methodology is presented for forecasting traffic volatility in urban arterial networks with real-time traffic flow information. This methodology provides a generalization of the standard modeling approach, in which both the mean, modeled by an autoregressive moving average process, and the variance, modeled by an autoregressive conditional heteroscedastic process, are time-varying. The statistical analysis and forecasting performance of the proposed model are investigated with real-time traffic detector data from a real urban arterial network. The results indicate the potential of the proposed model to improve the accuracy of predicted traffic volatility across different lengths of forecasting horizon in comparison with the standard generalized autoregressive conditional heteroscedastic methodology.

Application of Microscopic Simulation Model Calibration and Validation Procedure: Case Study of Coordinated Actuated Signal System

In the application of microscopic simulation models, the importance of model calibration and validation cannot be overemphasized. A recent study proposed a systematic approach for conducting a simulation model calibration and validation procedure on the basis of experimental design and optimization and applied it to an isolated intersection with a VISSIM simulation model. The present study further evaluates the previously developed simulation model calibration and validation procedure by applying it to an urban arterial network consisting of 12 coordinated actuated signalized intersections. Both VISSIM and CORSIM simulation models were used. Travel time was used for the calibration measure, and maximum queue length was used for the validation measure. Study results showed that calibrated and validated simulation models were able to represent field conditions adequately, whereas default parameter-based models could not. As such, the previously developed simulation model calibration and validation procedure...

Application of Microscopic Simulation Model Calibration and Validation Procedure

In the application of microscopic simulation models, the importance of model calibration and validation cannot be overemphasized. A recent study proposed a systematic approach for conducting a simulation model calibration and validation procedure on the basis of experimental design and optimization and applied it to an isolated intersection with a VISSIM simulation model. The present study further evaluates the previously developed simulation model calibration and validation procedure by applying it to an urban arterial network consisting of 12 coordinated actuated signalized intersections. Both VISSIM and CORSIM simulation models were used. Travel time was used for the calibration measure, and maximum queue length was used for the validation measure. Study results showed that calibrated and validated simulation models were able to represent field conditions adequately, whereas default parameter–based models could not. As such, the previously developed simulation model calibration and validation procedure was proved effective for an arterial network under both VISSIM and CORSIM simulation models.

Modelling vehicle interactions in microscopic simulation of merging and weaving

This paper presents data, collected from video-recording, on the microscopic details of merging and weaving manoeuvres under congested traffic conditions. Based on these observations, a classification of the manoeuvres into free, forced and cooperative lane changes is proposed. A new lane change model is developed, incorporating explicit modelling of vehicle interactions using intelligent agent concepts. The model was implemented in the ARTEMiS traffic simulator, and several hypothetical test studies were conducted to demonstrate the capabilities of the new model. The results show that the model is able to reproduce the observed behaviour of individual vehicles in terms of speed, gap acceptance and conflict-resolution in all three types of lane change manoeuvres, and hence, it is able to simulate highly congested flow conditions in a realistic manner. The macroscopic results in terms of speed-flow relationship are close to the typical expected results. The model can simulate both freeways and signalised urban arterial networks.

Modelling lane changing and merging in microscopic traffic simulation

This paper introduces Simulation of Intelligent TRAnsport Systems (SITRAS), a massive multi-agent simulation system in which driver-vehicle objects are modelled as autonomous agents. The simulation outputs can be used for the evaluation of Intelligent Transport Systems applications such as congestion and incident management, public transport priority and dynamic route guidance. The model concepts and specifications, and the first applications of the model in the area of incident modelling in urban arterial networks were described in previous publications. This paper presents the details of the lane changing and merging algorithms developed for the SITRAS model. These models incorporate procedures for ‘forced’ and ‘co-operative’ lane changing which are essential for lane changing under congested (and incident-affected) traffic conditions. The paper describes the algorithms and presents simulation examples to demonstrate the effects of the implemented models. The results indicate that only the forced and cooperative lane changing models can produce realistic flow-speed relationships during congested conditions.