CONGRESO |
 |
|
 |
89th Transportation Research Board Annual Meeting - TRB
Fecha: Washington, del 10 al 14 de enero de 2010
Presentación:
Congreso de carácter anual del Transportation Research Board (TRB), una de les institucions del National Research Council americano dedicada a la investigación en temas de Transporte.
Ponencias:
- "An interurban homogeneous Road Pricing model for a non-congested network: the Spanish case". Saurí, S., F. Robusté, M. Salas y J. Argote.
- "New Modifications to Bus Network Design Methodology". Foletta, N., M. Estrada, M. Roca-Riu y P. Martí.
- "Insights on Freexay Travel Time Estimation Methods Based on Punctual Speed Measurements". Soriguera, F. y F. Robusté.
- "Traffic Stream Space-Mean Speed Estimation from Common Double Loop Detector Aggregated Data". Soriguera, F. y F. Robusté.
- "Travel Time Forecasting and Dynamic OD Estimation in Freeways Based on Bluetooth Traffic Monitoring". Barcelo, J., L. Montero y L. Marques.
- "Decision Support System to Assist Design and Evaluation of City Logistics Applications with Real-Time Traffic Information". Barcelo, J. y A. Orozco.
|
|
PONENCIAS |
|
|
 |
An interurban homogeneous road pricing model for a non-congested network: the Spanish case.
Autores:Saurí, S., F. Robusté, M. Salas i J. Argote.
CongrESO: 89th Transportation Research Board Annual Meeting - TRB.
Fecha: Washington, del 10 al 14 de enero de 2010.
Idioma: inglés
Resumen:
Currently, there is not a homogeneous Road Pricing policy in Spain. Rather, various roads are tolled, though not in a uniform way and only taking into account financial considerations. For this reason, in this article we propose a Road Pricing policy to implement in the urban Spanish road network. After indentifying the various external costs derived from road traffic, we establish a toll structure that allows internalizing the externalities generated by the road network and the type of vehicles affected by the Road Pricing strategy. Finally, through a series of simulations we assess the effects that the different levels of the Road Pricing fulfillment have on the traffic flow.
|
|
 |
New Modifications to Bus Network Design Methodology.
Autores:Foletta, N., M. Estrada, M. Roca-Riu y P. Martí.
Congreso: 89th Transportation Research Board Annual Meeting - TRB.
Fecha: Washington, del 10 al 14 de enero de 2010.
Idioma: inglés
Resumen:
This article provides new methodology for solving the bus network design problem, covering both network design and frequency setting. Two new bus network design models are created which build upon the methodology proposed by Baaj and Mahmassani (1995). One modification includes the consideration that commercial speeds of buses vary depending on the aggregated frequency of buses on each street or corridor. A further modification is the updating of route frequencies during the route generation process. The models were applied to the street network of Barcelona. Outputs were compared and it was found that the new models produce bus networks with faster average travel speeds, smaller fleet size, less route kilometer, and fewer buses per link than prior methodologies. These results demonstrate that taking the variability of bus speeds and required route frequencies into consideration when performing route generation and frequency setting can significantly improve the performance of the bus network produced.
|
|
 |
Insights on Freeway Travel Time Estimation Methods Based on Punctual Spped Measurements.
Autores:Soriguera, F. y F. Robusté.
Congreso: 89th Transportation Research Board Annual Meeting - TRB
Fecha: Washington, del 10 al 14 de enero de 2010.
Idioma: inglés
Resumen:
The accuracy of the real-time travel information disseminated on metropolitan freeways is one of the key issues in the development of advanced traveler information systems. Although very accurate estimations could be obtained from the preexisting surveillance equipment installed on freeways: loop detectors. Travel time estimation from loop measurements has attracted much research effort during the laste decade, resulting in numerous methodologies. Among these, the ones that rely on spot speed measurements at detector sites to obtain the travel time estimation on the target stretch are the most intuitive. The key issue in these methods is the spatial generalization of point measurements over a freeway link. Multiple approaches can be found in literature, ranging from the simplest, and mostly implemented in practice, constant speed approach, to recent and more complex mathematical interpolations.
The present paper shows that all speed interpolation methods that do not coconsider traffic dynamics and queue evolution, do not contribute in better travel time estimations. All methods are inaccurate in congested and transitions, and the claimed relative benefits using various speed interpolation methods result from context specific experiments.
|
|
 |
Traffic Stream Space-Mean Estimation form Common Double Loop Detector Aggregated Data.
Autores:Soriguera, F. y F. Robusté.
Congreso: 89th Transportation Research Board Annual Meeting - TRB
Fecha: Washington, del 10 al 14 de enero de 2010.
Idioma: inglés
Resumen:
Wardrop [1] in one of the very first papers on traffic flow theory presented the difference between the space mean speed (SMS) and the time mean speed (TMS) of a group of traveling vehicles, and derived a relationship suitable for estimating TMS, given SMS and the speed variance over SMS. As time goes by, traffic practitioners have tended towards computing TMS instead of SMS, mainly when using double loop detectors, and nowadays this is the usual practice in traffic management centers. Therefore, the useful relationship between TMS and SMS should go the other way around in relation to Wardrop’s. Recently, Rakha and Zhang [2] proved the complementary relationship, suitable for estimating SMS from TMS and the speed variance over TMS. However this is not enough, as speed variance is usually not available. The present paper develops a probabilistic method to estimate SMS from TMS without the previous knowledge of speed variance and only using the usual time aggregations of loop detector data.
The main assumption of the method – the normality of vehicle speed distribution – is discussed and a formulation to obtain the expected error of the estimation is derived. The results obtained with test data from the AP-7 highway, near Barcelona in Spain, show that the developed methodology is able to estimate SMS with an average relative error as low as 0.5%.
|
|
 |
"Travel Time Forecasting and Dynamic OD Estimation in Freeways Based on Bluetooth Traffic Monitoring."
Autores:Barceló, J., L. Montero y L. Marques.
Congreso: 89th Transportation Research Board Annual Meeting - TRB
Fecha: Washington, del 10 al 14 de enero de 2010
Idioma: inglés
Resumen:
From the point of view of the information supplied by an ATIS to the motorists entering a freeway of one of the most relevant is the Forecasted Travel Time, that is the expected travel time that they will experience when traverse a freeway segment. From the point of view of ATMS the dynamic estimates of time dependencies in OD matrices is a major input to dynamic traffic models used for estimating the current traffic state and forecasting its short term evolution. Travel Time Forecasting and Dynamic OD Estimation are two of the key components of ATIS/ATMS and the quality of the results that they could provide depend not only on the quality of the models but also on the accuracy and reliability of the measurements of traffic variables supplied by the detection technology. The quality and reliability of the measurements produced by traditional technologies, as inductive loop detectors, is not usually the required by real-time applications, therefore one wonders what could be expected from the new ICT technologies as for example Automatic Vehicle Location, License Plate Recognition, detection of mobile devices and so on. The main objectives of this paper are: to explore the quality of the data produced by the Bluetooth detection of mobile devices equipping vehicles for Travel Time Forecasting and its use to estimate time dependent OD matrices. Ad hoc procedures based on Kalman Filetering have been designed and implemented successfully and the numerical results of the computational experiments are presented and discussed.
|
|
 |
"Decision Support System to Assist Design and Evaluation of City Logistics Applications with Real-Time Traffic Information."
Autores:Barceló, J. y A. Orozco
Congreso: 89th Transportation Research Board Annual Meeting - TRB
Fecha: Washington, del 10 al 14 de enero de 2010
Idioma: inglés
Resumen:
The design and evaluation of City Logistics applications requires an integrated framework in which all components could work together. Therefore City Logistics models should account for vehicle routing applications and fleet management models able of including also the dynamic aspects of the underlying road network, namely when ICT applications are taken into account. This paper develops a methodological proposal based on an integration of vehicle routing models and real-time traffic information. In the computational experiments conducted in the paper a dynamic traffic simulation model has been used to emulate the actual traffic conditions providing at each time interval the estimates of the traffic state on each link of the road network, the information that will be used by a real time fleet management system to determine the optimal dynamic routing and scheduling of the vehicle.
|
|
|
