Transport Management - Thematic Research Summary

Transport Research Knowledge Centre
September 2009
*2010 Update



This paper covers the management of traffic and transport services for all modes, including changing the way in which existing transport systems are used and the strategic and tactical control of traffic. It is based on results of projects covering mobility & traffic management in urban areas, freight & logistics management, and traffic & network management for road, rail, waterways and airspace.

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Night-time traffic in urban areas: A literature review on road user aspects

VTI - Sweden
June 2009

The aim of this literature study is to review recent research on night-time traffic from a road user perspective. The report discusses road users’ behaviour, needs and problems in relation to other road users as well as to traffic environment. The study includes 128 references from 1998–2008 and it mainly concerns urban areas.

The report begins with a chapter about accident statistics, followed by a theoretical background that includes lighting terminology, Swedish regulations on road equipment, and the human eye and night vision. The main part of the report has its focus on five road user groups - drivers, pedestrians, bicyclists, older people and visually impaired people - and their needs, difficulties, performances and behaviour in night-time traffic.

The literature gives relatively much information about drivers'situation in night-time traffic, but there is a lack of knowledge in some areas such as drivers' interaction with parts of the driving environment. Also, there is partly a lack of knowledge on pedestrians and older road users. Regarding bicyclists and visually impaired people, there is only very few limited literature available.

Several areas that are interesting for further research are identified in the report

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Gravity, Distance, and Traffic Flows in Mexico

Roberto Duran Fernandez
Transport Studies Unit - Oxford University Centre for the Environment
Working paper N° 1030
January 2008

This paper presents an econometric analysis that compares the performance of different measurements of distance in a gravity model using state data in Mexico. The estimation shows that at this geographical scale, the definition of distance does not affect significantly the explanatory power of the model. However, time-based definitions of distance have a marginal improvement on the model fit in comparison to length-based measures. When geographic specific fix effects are unknown, the model shows that distance measured through the transport network is a better predictor. The results conclude that time-based definitions of distance present several advantages in comparison to traditional length-based definitions. Another implication is that at large geographic scale, where relative distances between every geographic unit are large, the use of length-based distance instead of time to approximate travel costs generates similar results.

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Congestión de tránsito: el problema y cómo enfrentarlo

Cuadernos de la CEPAL Nº 87
Julio 2003

Este libro tuvo su origen en el reconocimiento del avance de la congestión de tránsito en las grandes ciudades y la necesidad de plantear medidas eficaces para mantenerla bajo control a fin de salvaguardar la calidad de vida y sostenibilidad urbanas. El texto fue producido en la Unidad de Transporte de la CEPAL, en el marco de un proyecto que contó con el generoso apoyo del Gobierno de Alemania y de la Agencia Alemana de Cooperación Técnica (GTZ). Asimismo, se obtuvo la gentil autorización del Ministerio de Planificación y Cooperación de Chile para el empleo de los modelos de tránsito ESTRAUS, VERDI y MODEM.

Los problemas descritos en este libro, así como las diferentes formas de enfrentar la congestión, se han preparado teniendo en cuenta las condiciones de las grandes ciudades de América Latina y el Caribe. Sin embargo, lo que aquí se presenta posiblemente también sea válido para muchas otras áreas geográficas del mundo, pudiendo considerarse un marco general destinado a enfrentar el flagelo de la congestión de tránsito urbano.

La congestión de tránsito ha ido en aumento en gran parte del mundo, desarrollado o no, y todo indica que seguirá agravándose, constituyendo un peligro cierto que se cierne sobre la calidad de vida urbana. El explosivo aumento del parque de automóviles y el indiscriminado deseo de usarlos, por razones de comodidad o estatus, especialmente en los países en desarrollo, ejercen una gran y creciente presión sobre la capacidad de las vías públicas existentes.

Los fuertes impactos negativos de la congestión, tanto inmediatos como de largo plazo, exigen esfuerzos multidisciplinarios para mantenerla bajo control, mediante el diseño de políticas y medidas apropiadas, no siendo sencillo encontrar las soluciones más indicadas. Todo señala que debe intentarse un conjunto de acciones sobre la oferta de transporte, así como sobre la demanda, a fin de racionalizar el uso de las vías públicas.

El control de la congestión forma parte de la elaboración de una visión estratégica de largo plazo del desarrollo de una ciudad, que permita compatibilizar la movilidad, el crecimiento y la competitividad, tan necesarias actualmente, con la sostenibilidad de la urbe y su calidad de vida. El tema es complicado y exige una alta capacidad profesional y de liderazgo de parte de las autoridades urbanas y de transporte. El trabajo ha de ser continuo y permanente. En este libro se presentan herramientas existentes para abordarlo, unas más efectivas que otras, unas más aceptadas que otras, pero un conjunto de ellas, que cuente con soporte ciudadano, hará posible defenderse para no sucumbir ante el moderno flagelo de la congestión.

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Results of a field study on a driver distraction warning system

VTI
March 2009

An extended field study on driver distraction and drowsiness was conducted in an instrumented vehicle, which was equipped with an eye tracker and other sensors. This report focuses on the findings concerning driver distraction. Seven participants used the car just as their own car during a period of one month each. During the baseline phase, which comprised of the first ten days of the trial the distraction warnings were deactivated. During the treatment phase, consisting of the remaining 20 days, the warnings were activated, meaning that the driver received a vibration in the seat whenever an algorithm called AttenD determined that the driver was distracted from the driving task. The participants’ subjective opinion about the warning systems was assessed with the help of three questionnaires.
The method is promising for driver distraction research, as it investigates naturalistic behaviour in a naturalistic setting. The employed eye tracker held up to the expectations, even though it is recommendable for future research to use more than two cameras. With the current setup, there was a tendency that tracking was lost just when driver distraction occurred. A robust data acquisition system is a requirement.
The main finding was that the drivers’ gaze behaviour was not influenced much by the distraction warnings. The drivers received distraction warnings at about the same frequency during the treatment phase as they would have during the baseline phase. This indicates that they did not avoid the warnings. Performance indicators like “percent road centre” and the newly developed percentage of glances within the “field relevant for driving” did not change from baseline to treatment phase. The standard deviation of gazes did not change, either. The average percentage of very long glances decreased slightly in the treatment phase, suggesting that the warning had an effect on the more extreme glance behaviour. There are also indications that the system helped prevent further extended glances away from the road immediately after a warning was issued.
The results from the questionnaire indicate that the drivers were satisfied with AttenD. Their expectations had been positive, and they indicated no disappointment. The drivers stated that they trusted the system, that the warnings were not experienced as disturbing, and that the system made them more aware of what they did while driving. Some drivers reported using their cell phones less while driving as a consequence of the warnings.
The analyses presented here are of a rather general nature, and more detailed analyses could provide new insights and a more differentiated picture of the usefulness of the driver distraction warning system. It is also important to investigate whether AttenD influenced driving behaviour like speed choice or steering variables.
A general problem with driver distraction research is the absence of a ground truth, which could be used as a benchmark, against which distraction detection algorithms could be compared and evaluated.

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Distraction and drowsiness – a field study. Technical report

VTI
April 2009

The main goal of the distraction and drowsiness field study was to evaluate a system for detecting driver distraction and drowsiness. This report focuses on the system implementation and the algorithms detecting distraction and drowsiness. A previous report dealt with the background of driver distraction, the results of the study are presented in a further report.

A vehicle was instrumented with video cameras, an automatic eye tracker and GPS receivers. Further data were read from the CAN bus of the car. The data were logged continuously with high frequency as long as the ignition was on. The log system operated autonomously and was switched on with the turning of the ignition key. Seven participants drove the vehicle during one month each. During the first ten days the distraction and drowsiness warning system was deactivated, in order to collect a behavioural baseline. After this the warnings were activated, such that the driver received distraction warnings in form of a vibration in the seat when the algorithm determined that they had looked away from the forward roadway too much. A separate algorithm judged whether the drivers were drowsy or not. Three drowsiness levels existed, which led to three different warnings with increasing intensity for increasing drowsiness. The eye tracking system installed in the car afforded real time eye tracking, which is necessary for giving glance direction based or blink duration based warnings in real time.

The participants filled in questionnaires about their driving habits, their attitudes about driver distraction and drowsiness, and their expectations towards the warning system as well as their experiences with the system. A number of questionnaires were administered on three occasions during the course of the study.

No major problems were encountered during the field study, but a number of smaller problems had to be solved. However, in the end of the data collection period the computer installed in the car became more and more unstable, which led to increased data loss. Again, piloting was shown to be essential, as well as a clear delimitation of the goals and hypotheses of the project.

The obvious potential of the distraction detection system was pointed out by the positive comments of the participants, but having a system which is reliable in all situations and for all drivers is still a difficult task.

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