Traffic Model of a Microregion

Abstract

This paper introduces a new concept of the state model of one traffic microregion based on a maximum utilization of information from all measured traffic variables. The aim of the model is to estimate length of queues that are formed on arms of junctions with traffic lights. This task is trivia in case of complete knowledge of all measured traffic quantities for all junction arms. Then the model only counts simply the queue length from input and output intensities. However, the net of all needed detectors is not usually complete and some significant traffic flows (parking cars, etc.) are not measurable in practice. The model estimates the queue length in this case. In the end of the paper,the model and estimation algorithm is tested for several types of disturbances which can arise in reality. At least partially, these experiments illustrate the functionality and effectiveness of the proposed model for estimating queue lengths on the junction arms in the real traffic.

Distributed Bayesian Decision-Making for Urban Traffic Control

“…Note that ξ t follows ξ sim,t with two interesting anomalies: At the beginning of the rush hours, the model tends to underestimate the queues, while it severely overestimates the queues in the evening. The reason of this behaviour may be twofold: (i) the linear coefficients and the variance of (11)- (12) are chosen from empirical rules [7], which may not be accurate, and (ii) the learning of the non-linear model of the internal variables involves approximations-such as projections onto (16)-which are not globally optimal, i.e. the error of approximation may be accumulated.…”

“…The traffic flow is modelled using a particle flow model [7]. This is a special case of state-space model [10], where the state Θ t consists of the queue lengths ξ t and some extra entries (see below).…”

An Empirical Model of Occupancy-Queue Relation

“…Our queue model is inspired by Diakaki (1999) and it is based on the experiments with existing queue length estimation model of Homolová and Nagy (2005). This model does not behave well for high-occupancy situations and provides a point estimate only.…”

“…In the last few years the research group at UTIA developed first approximation of a state-space queue length model for urban arteries based on ideas of Homolová and Nagy (2005). This model is based on vehicle conservation law and non-linear Kalman filtering, and uses solely information from strategic upstream detectors.…”

Application of Estimation Techniques on Queue Lengths Estimation in Traffic Network

“…In case of Prague, the system MOTION sets to long cycle times of traffic lights. For this reason the novel non-commercial adaptive traffic control system has been proposed [6], [7]. This novel adaptive traffic control system is being developed especially for the needs of cities with old urban areas, which are characterised by narrow and short roads, one-way roads, and by large number of both uncontrolled and controlled intersections.…”