Personal Mobility

This paper describes simulation studies on the effect of the inter-vehicle communications on the
improvement of traffic flow along an expressway, and shows the relationship between the
penetration rate of the communication unit and suppression of the shock wave. In the simulation,
20 vehicles are assumed to drive at the same speed of 15 [m/s] and the same headway of 2 [s] or
2.5 [s] along a single lane, and then the lead vehicle slows down with the acceleration of -1 [m/s2]
for 2 [s] and then speeds up with the acceleration of 1 [m/s2] for 2 [s]. If a vehicle is equipped with
a communication unit, it can control the speed without any delay with the data transmitted from a
preceding vehicle to prevent the shock wave to propagate upstream. The simulation results show
that the effective penetration rate of a communication unit is at least 20 % and 10 % for the
headways of 2 [s] and 2.5 [s] respectively.

Department of Information Engineering, Meijo University

Presented at the ITS America Annual Conference and Exposition, November 16-20, 2008, New York, New York

Congestion on urban freeways, which adversely affects the economy, environment, and quality of life, continues to be a major problem in the United States. Minor incidents, such as minor traffic accidents, stalled vehicles, and special events, account for the majority of urban freeway congestion. Due to the problems associated with freeway incidents, many large metropolitan areas have implemented Incident Management Systems (IMS) to alleviate congestion and safety problems associated with incidents. These systems provide motorists with timely and accurate information to avoid incident locations. Therefore, motorists will experience reductions in travel time and secondary accidents, while increasing speeds and capacity during an incident. Incident management systems have been implemented mainly in large urban areas; however, little is known about the possible benefits in smaller urban areas (second-tier cities).

This study examined the feasibility of implementing IMS in small/medium size urban areas using a case study of the I-29 corridor in Fargo, ND. Due to the lack of knowledge and information regarding the possible benefits of implementing an IMS in smaller urban areas, the evaluation was performed using a simulation model to compare base cases to ITS enhanced cases. The INTEGRATION simulation model was used to estimate the potential benefits of an IMS which employs Advanced Traveler Information Systems (ATIS) and Advanced Traffic Management Systems (ATMS). The study simulated a hypothetical one-lane-blocking incident having a duration of 20 minutes.

The case study analysis revealed that the combination of ATIS and ATMS provided the most favorable network benefits under the 20-minute incident. The IMS reduced incident travel times by 13 percent (city arterials), 28 percent (freeways), and 18 percent (overall network); average trip times were reduced by 20 percent (overall network); and average speeds increased by 21 percent (overall network).

North Dakota State University - Advanced Traffic Analysis Center - Upper Great Plains Transportation Institute

Presented at the 10th ITS Annual Conference and Exposition, May 1-4, 2000 Boston, MA

This paper is concerned with a study of novel mathematical model of macro-
scopic road network mobility. The approach taken herein is based on the well estab-
lished framework, called cell transmission model (CTM). However, the conventional
CTM (herein called S-CTM) cannot capture the mixed composition of vehicle types
(e.g. truck, car, bus or smaller vehicles), the essence of which is critical to many
applications in practice. CTM is therefore originally generalized into so-called M-
CTM in this paper so as to consider the heterogeneous mobility, i.e. with more than
one class of vehicles. Both S-CTM and M-CTM are compared with the simulated
result in microscopic level from MITSIM software of MIT. The obtained results
suggest that M-CTM is more accurate than S-CTM significantly in uncongested
network with non-stationary vehicle composition without compromising on the
computational complexity. It is therefore expected that the proposed M-CTM would
be well applicable to model large-scale road systems like expressway or highway
systems with heterogenous mixtures of vehicle types.

Chulalongkorn University, Thailand

Presented at the ITS America Annual Conference and Exposition, November 16-20, 2008, New York, New York

Nowadays there’s an increasing need to guarantee people’s mobility at acceptable cost and in
safe conditions, and to provide mobility related services according to the user’s profile. Safety
and comfort, co-operation between vehicle and infrastructure or service centre, configurable
human machine interfaces according to user’s profile, are key concepts which will
characterise the future vehicles. In this context, special care has to be dedicated to elderly
people’s needs as road users. OASIS Integrated Project comes to fill this by proposing an
elderly friendly transportation information system and route guidance, as well as technologies
for promoting personal mobility. In this paper emphasis is given to the personal mobility
promotion, by developing elderly drivers’ real time stress and discomfort assessment
algorithms and automatic seat and key vehicle configuration elements.

Centre for Research & Technology Hellas/Hellenic Institute of Transport

Presented at the 15th World Congress on Intelligent Transport Systems, November 16-20, 2008, New York, New York

The number of injuries in traffic accidents in Japan has exceeded one million for nine
consecutive years in 2007, and reducing the number of traffic accidents remains an important
issue. We believe that reducing situation which may lead to traffic accidents, is an effective
means of helping to reduce the number of traffic accidents. This study utilized a questionnaire
investigation to collect examples of traffic incidents which occur during ordinary driving, and
analyzed the driver behavior and driver’s mental and physical states immediately before
encountering the traffic incident. Based on this analysis, we clarified the driver characteristics
which tended to make traffic incidents more likely.
We also conducted a comparison with the regression analysis results from previous research
concerning subjective daytime sleepiness which is thought to be one of factors that is likely to
lead to serious accidents. Based on these results, we propose a direction for further research
concerning next generation driving support systems that detect information on driver’s
physiological signals in order to help prevent traffic accidents.

TOYOTA INFOTECHNOLOGY CENTER Co., LTD.

TOYOTA MOTOR CORPORATION

Aichi Prefectural University

Presented at the 15th World Congress on Intelligent Transport Systems, November 16-20, 2008, New York, New York