Showing papers by "Haibo Chen published in 2010"
TL;DR: In this paper, a method was developed to estimate Origin Destination (OD) matrices using a neural network (NN) model and loop traffic data collected from a UK motorway site (M42) as the primary input.
14 citations
26 Jul 2010
TL;DR: In this article, the authors summarized the action schemes and what's on now in Beijing and summarized the current state of green transport in the city of Beijing, including exploration of low emission vehicles, priority to public transport, cycling and walking improvement and intelligent information techniques application.
Abstract: Beijing is a city with a history of about 3,000 years. In the past several decades, pursuing to be industrialized used to be a main goal of the city which caused more and more serious pollution problems. Since the late of 1990s, actions have been taken to deal with the air pollution in Beijing in order to enhance living level of its residents. However, countermeasures taken firstly were almost on the adjustment of development routine of industry. Until recent years, especially approaching the 2008 Olympic Games, complicated schemes on green transport was concretely carried out. It was not only aiming for a currently clean air, but also a future sustainable development of transport and urbanization. Among the actions taken on green transport, there are exploration of low emission vehicles, priority to public transport, cycling and walking improvement and intelligent information techniques application. This paper summarizes these action schemes and what’s on now in Beijing.
3 citations
01 Jan 2010
TL;DR: In this article, the authors focused on the assessment of the congestion impacts of fatal accidents and used the SCOOT traffic control system to provide an assessment of these impacts in more heterogeneous urban environments, with only accidents that occur in either peak periods or constricted network layouts producing significant induced congestion externalities.
Abstract: This study focuses on the assessment of the congestion impacts of fatal accidents. The paper addresses the current paucity of research into accident induced congestion levels outside of Motorway/Freeway environments, and using the SCOOT traffic control system, provides an assessment of these impacts in more heterogeneous urban environments. Levels of induced congestion are found to vary significantly according to the temporal and spatial settings in which they occur, with only accidents that occur in either peak periods or constricted network layouts producing significant induced congestion externalities in monetary terms. The detailed spatial and temporal resolutions required for such forecasts are subsequently discussed, as these raise a number of issues for SCOOT and ITS data more generally, if such analyses are to become more detailed, sophisticated, and ultimately automated, across a range of complex temporal and spatial settings.
2 citations
Posted Content•
TL;DR: In this article, a Bayesian multiple change point model is proposed to analyse violations of air quality standards by pollutants such as nitrogen oxides (NO2 and NO) and carbon monoxide (CO).
Abstract: A Bayesian multiple change-point model is proposed to analyse violations of air quality standards by pollutants such as nitrogen oxides (NO2 and NO) and carbon monoxide (CO). The model is built on the assumption that the occurrence of threshold exceedances may be described by a non-homogeneous Poisson process with a step rate function. Unlike earlier approaches, our model is not restricted by a predetermined number of change-points, nor does it involve any covariates. Possible short-range correlations in the exceedance data (e.g., due to chemical and meteorological factors) are removed via declusterisation. The unknown rate function is estimated using a reversible jump MCMC sampling algorithm adapted from Green (1995), which allows for transitions between parameter subspaces of varying dimension. This technique is applied to the 17-year (1993-2009) daily NO2, NO and CO concentration data in the City of Leeds, UK. The results are validated by running the MCMC estimator on simulated data replicated via a posterior estimate of the rate function. The findings are interpreted and discussed in relation to some known traffic control actions. The proposed methodology may be useful in the air quality management context by providing quantitative objective means to measure the efficacy of pollution control programmes.