IATSS Review
Online ISSN : 2433-4537
Print ISSN : 0386-1104
Current issue
Speed Management and Road Traffic
Showing 1-10 articles out of 10 articles from the selected issue
Opinions
Special Supplement : Speed Management and Road Traffic
Introduction
Information
  • Yasuhiro SHIOMI
    2021 Volume 45 Issue 3 Pages 172-181
    Published: February 28, 2021
    Released: March 03, 2021
    JOURNALS FREE ACCESS

    Dynamic speed management on motorways has been adopted in many Western Countries, while it is not common in Japan. This paper introduces the overview of the system, theoretical background and its effect on traffic flow and level of service based on literature reviews. Furthermore, the results of comparative analysis on the perception of the ordinary drivers to speed limits on motorways between Japan and UK are reported. Finally, we discuss the future challenges and possibilities for installing the dynamic speed management on motorways in Japan.

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Information
  • ISA, Portable Orbis and Average Speed Enforcement
    Kojiro MATSUO
    2021 Volume 45 Issue 3 Pages 182-189
    Published: February 28, 2021
    Released: March 03, 2021
    JOURNALS FREE ACCESS

    This paper introduces relatively new technological trends in engineering and enforcement approaches used for speed management. Specifically, this paper introduces the trends involving “Intelligent Speed Adaptation (ISA)” and “Average Speed Enforcement”, which have been studied and demonstrated in European countries since around 2000, and “portable Orbis”, which is a new speed enforcement technology in Japan. This paper then describes the approaches used to evaluate the impact of speed enforcement.

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Report
  • Nobuhiro YANO, Toshiya YOKOZEKI, Kenji MORI
    2021 Volume 45 Issue 3 Pages 190-197
    Published: February 28, 2021
    Released: March 03, 2021
    JOURNALS FREE ACCESS

    The maximum speed of certain sections of expressway were raised above 100km/h on a trial basis starting in November 2017. This paper reports the results of a study case that examines the impact this increase in the maximum speed had on traffic conditions. This study looked at the effect that the increase in the speed limit to 110km/h and 120km/h had from three different perspectives – changes in the travel speed, changes in the frequency of lane changes, and changes in the risk of collision when overtaking based on the margin-to-collision index. Although the data collected through to March 2019 did not show any significant effect of raising the maximum speed limit, some interesting changes were brought to light. The effects of raising the maximum speed limit will require further observation over a longer time span in the future.

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Report
  • Shingo MORIIZUMI, Shinnosuke USUI
    2021 Volume 45 Issue 3 Pages 198-205
    Published: February 28, 2021
    Released: March 03, 2021
    JOURNALS FREE ACCESS

    The present study examined the effect of providing education aimed at reduction of the time-saving bias (referring to the driver’s cognitive bias of overestimating time saved by accelerating in a high-speed area), which affects the driver’s speed selection. Specifically, before measurement of the time-saving bias, twenty-seven university students with driver’s licenses were trained to calculate the time saved by accelerating when the speed was displayed as either “s/km” or “km/h.” The results of the present study indicated that the time-saving bias occurred in the former case, but not in the latter case. The findings also suggested that the extent of the time-saving bias was not related to the driving behaviors in the driving simulator.

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Report
  • Kyoko MANAKA, Akihiro NAKAMURA, Akinori MORIMOTO
    2021 Volume 45 Issue 3 Pages 206-215
    Published: February 28, 2021
    Released: March 03, 2021
    JOURNALS FREE ACCESS

    In this paper, we examined the existence of regional differences in driving speed awareness, mainly between prefectures, using nationwide questionnaire survey data. Our results show that there were no regional differences in driver awareness of the road speed limit while driving on roads in terms of simple trends, namely differences in residential areas such as urban areas and rural areas and differences while driving between prefectures. On the other hand, when looking at the driver’s speed adjustment behavior in speed controlled zones or school zones, it was clear to see that speed adjustment behavior is similar in neighboring prefectures, but there are regional differences when the physical distance increases.

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Information
Information
  • Shin KATO
    2021 Volume 45 Issue 3 Pages 222-231
    Published: February 28, 2021
    Released: March 03, 2021
    JOURNALS FREE ACCESS

    This article introduces low-speed mobility, which is expected to be used in spaces of coexistence as a means of transportation in residential areas, etc., as one of the solutions to transportation problems in Japan, a super-aging society. First, I will introduce the types and categories of vehicles used for low-speed mobility, as well as their advantages and disadvantages. In addition, as utilization examples, I will indicate, for example, demonstration and commercialization cases, such as green slow mobility. Furthermore, I will introduce a demonstration experiment on low-speed mobility utilizing automated driving technology, and describe issues and future developments.

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Contribution
Paper (Peer reviewed)
  • Kunio MIYASHITA
    2021 Volume 45 Issue 3 Pages 232-241
    Published: February 28, 2021
    Released: March 03, 2021
    JOURNALS FREE ACCESS

    Among advanced logistics countries and regions, which has the strongest competitive power? Both the World Bank research, based on results from a global scale questionnaire, and my comparative empirical analysis on the competitive power of major logistically advanced countries demonstrate that the EU has an overwhelming competitive advantage. The purpose of this paper is to endeavor to find the source of the EU’s logistics competitive power. After considering alternate behavior of air and sea transport in major countries developed with the EU as the export base using two axes analysis for a postponement business model based on the expected freight rate and direct investment behavior, which is the trigger for such a model, it can be concluded that the EU’s logistics competitive power lies in their ability to rationally build an excellent business model that has the ability to self-adjust, which distinguishes it from others.

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