Quarterly Report of RTRI
Online ISSN : 1880-1765
Print ISSN : 0033-9008
ISSN-L : 0033-9008
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Showing 1-12 articles out of 12 articles from the selected issue
PERSPECTIVES
  • Kunihiro KAWASAKI
    Type: research-article
    2020 Volume 61 Issue 4 Pages 235-239
    Published: November 01, 2020
    Released: November 26, 2020
    JOURNALS FREE ACCESS

    Various systems using Information Technology (IT) have been developed for automating or supporting train operation and traffic management. However, some tasks still depend on the experience and knowledge of dispatchers. For this reason, dispatchers are subject to significant pressure, not only for daily traffic management, but even more when dispatching operations in case of emergencies or disasters. Dispatchers who manage train operations and control traffic need to make quick decisions based on a large amount of information, so it is required to reduce the difficulty and load of dispatchers. Recent years have seen the development of systems for predicting and/or making decisions about train operations, using Information and Communication Technology (ICT), such as Artificial Intelligence (AI) and big data analysis, in order to alleviate the pressure placed on dispatchers and reduce the time required for resuming train operations after a disruption, based on information on passenger flow, operating conditions, weather conditions, etc. This paper introduces plans for R & D relating to train operation management support systems using ICT, to be included in the next multi-year RTRI master plan which will run from FY 2020, based on R & D conducted during the RTRI master plan which ran from FY2015 to Y2019.

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  • Kiyoshi NAGAKURA
    Type: research-article
    2020 Volume 61 Issue 4 Pages 240-243
    Published: November 01, 2020
    Released: November 26, 2020
    JOURNALS FREE ACCESS

    Aerodynamic phenomena cause various problems on railways. The improvement of the aerodynamic characteristics of railway vehicles and infrastructures can increase the value of railways from the view point of safety, convenience, harmony with the environment, cost reduction, etc. This paper introduces the outlines of the recent studies on railway aerodynamics and noise conducted by the Railway Technical Research Institute.

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  • Koji OMINO
    Type: research-article
    2020 Volume 61 Issue 4 Pages 244-248
    Published: November 01, 2020
    Released: November 26, 2020
    JOURNALS FREE ACCESS

    In order to improve railway safety, from a human factor point of view, the Human Science Division of the Railway Technical Research Institute in Japan, has been conducting research for the prevention of human errors, their education and training, and the countermeasures for railway accidents caused by the external factor. This paper outlines recent topics of research based on current issues facing railways.

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PAPERS
  • Daiki OKUDA, Takamasa SUZUKI, Noriko FUKASAWA, Naoya OZAKI
    Type: research-article
    2020 Volume 61 Issue 4 Pages 249-255
    Published: November 01, 2020
    Released: November 26, 2020
    JOURNALS FREE ACCESS

    In a railway business, recovery strategies for quick recovery of railway transportation after large-scale disasters are becoming important more and more. First, this paper describes a mathematical algorithm for calculating a railway network recovery plan constituting a basic part of a decision-making support method of a railway transportation recovery strategy. Secondly, it describes the outline and the result of the recovery simulation conducted to verify the feasibility and validity of the algorithm. Finally, it outlines the development status of other parts of the decision-making support method except the algorithm. It also outlines future development plans of the method.

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  • Takamasa SUZUKI
    Type: research-article
    2020 Volume 61 Issue 4 Pages 256-260
    Published: November 01, 2020
    Released: November 26, 2020
    JOURNALS FREE ACCESS

    The ISO/TR 21245 Technical Report, focusing on the planning processes involved in railway projects, was successfully published in November 2018 following fruitful discussions in the document-developing working group, ISO/TC 269/WG 3, of the International Organization for Standardization. This TR is expected to play an important role in preparing appropriate plans for railway projects which take into account factors that can make the project successful. This article outlines the TR, describes its benefits, and gives some background about how the document was developed.

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  • Shingo NAKAGAWA, Takamasa SUZUKI, Ryosuke MATSUMOTO, Noriko FUKASAWA, ...
    Type: research-article
    2020 Volume 61 Issue 4 Pages 261-266
    Published: November 01, 2020
    Released: November 26, 2020
    JOURNALS FREE ACCESS

    One approach for increasing the revenue of railway undertakings is to adopt yield management techniques, by setting quotas for discount ticket sales of reserved seats on express trains. We developed a method to calculate the optimum sales quota, incorporating estimations for the demand of various discount tickets and purchase behavior of passengers with the next-best-option when they were not able to buy their desired ticket. We conducted a trial sale by applying the calculated sales quota into the actual seat reservation system and confirmed that the method can increase revenues and facilitate decision-making for setting sales quotas.

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  • Hajime TAKAMI
    Type: research-article
    2020 Volume 61 Issue 4 Pages 267-272
    Published: November 01, 2020
    Released: November 26, 2020
    JOURNALS FREE ACCESS

    To shorten stopping distances of high-speed trains in case of emergency braking, the author of this paper developed a small, light-weight aerodynamic braking device. To examine its aerodynamic characteristics, a full-scale prototype was tested in a wind tunnel facility at a maximum flow speed of 400 km/h. Tests confirmed that the response time for deployment of the device was only 0.39 s, and that the prototype was able to produce an aerodynamic drag force of 2.3 kN per unit. In addition, performance was calculated using computational fluid dynamics (CFD). The result of the CFD analysis around a train roof with a large number of devices showed that the staggered arrangement of the devices could increase the total drag force by 10 percent compared to the standard parallel arrangement.

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  • Tsugutoshi KAWAGUCHI, Takeshi SUEKI, Toshiki KITAGAWA
    Type: research-article
    2020 Volume 61 Issue 4 Pages 273-277
    Published: November 01, 2020
    Released: November 26, 2020
    JOURNALS FREE ACCESS

    It is well-known that wheel/rail noise from 250 Hz to 4 kHz has a greater influence on wayside noise along railway lines. However, when a train runs on a gently curved section, noise due to wheel and rail vibrations above 10 kHz could have a greater contribution to the total wayside noise. This paper therefore investigated the contribution of the high-frequency noise to wayside noise on a high-speed railway line through field tests and static experiments. It was found that wheel noise above 10 kHz is generated mainly by the leading wheel on the outside rail of each bogie, and that the noise level depends on train speed.

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  • Hidehiko OKUBO, Takashi FUKUDA, Tokuzo MIYACHI, Sanetoshi SAITO
    Type: research-article
    2020 Volume 61 Issue 4 Pages 278-283
    Published: November 01, 2020
    Released: November 26, 2020
    JOURNALS FREE ACCESS

    Micro-pressure waves (MPWs) radiated from a tunnel portal were numerically analyzed using unsteady acoustic analysis. First, the compression waveforms at the tunnel entrance were decided by linear acoustic analysis. Next, the nonlinear distortion of the compression waveform accompanying tunnel propagation was calculated using 1D theoretical propagation equation. Finally, the radiated MPWs were calculated by point source approximation. This research demonstrates that even if the difference in the waveform of the compression waves is slight at the tunnel entrance, it appears as considerable difference in MPW when the effects of the nonlinear distortion of the compression wave are taken into account.

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  • Akiko MURAKOSHI, Yumeko MIYACHI, Mami MATSUMOTO, Toshiaki KABURAGI, Ka ...
    Type: research-article
    2020 Volume 61 Issue 4 Pages 284-289
    Published: November 01, 2020
    Released: November 26, 2020
    JOURNALS FREE ACCESS

    By conducting opinion surveys among on-site railway personnel, the authors demonstrated that training about "processes" and raising awareness about how non-compliance of rules leads to accidents, is necessary in order to promote further rule compliance. On the basis of this result, three pedagogical tasks based on group discussion and four pedagogical tasks for hands-on experience were developed. Six educational programs combining these seven pedagogical tasks were trialed and the following findings were confirmed: satisfaction among trainees on the educational programs was high; attitudes to rule compliance among participants continued to improve even one month after the training; the extra workload and responsibility imposed on site managers tasked with conducting the training was within the limits of what was considered acceptable for their role.

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  • Ayanori SATO, Noriko ONOMA, Takayuki MASUDA
    Type: research-article
    2020 Volume 61 Issue 4 Pages 290-296
    Published: November 01, 2020
    Released: November 26, 2020
    JOURNALS FREE ACCESS

    This article proposes the use of calling as a method to help train drivers avoid exceeding speed limits. The prospective calling consists of mental-imagery calling and repetition calling. ‘Mental-imagery calling' refers to an action where a driver voices out loud the mental image they have of their driving in restricted speed sections. Repeated calling involves a driver repeating reminders to themselves as they operate the train. The effects of these two types of calling to improve prospective memory recall were confirmed experimentally. In addition, the effect of prospective calling on preventing excessive train speeds was confirmed in an experiment involving train drivers, using a train driving simulator.

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  • Masateru IKEHATA, Yukihisa SUZUKI, Atsushi SAITO, Sachiko YOSHIE
    Type: research-article
    2020 Volume 61 Issue 4 Pages 297-302
    Published: November 01, 2020
    Released: November 26, 2020
    JOURNALS FREE ACCESS

    International guidelines that aim to protect people from adverse health effects of exposure to magnetic fields (MF) have been established by international organizations such as the International Commission on Non-Ionizing Radiation Protection (ICNIRP) or the Institute of Electrical and Electronic Engineers (IEEE). In these guidelines, one of the target effects below 100 kHz is nerve stimulation based on a few perceptual studies. Because of a few studies, the value of basic restriction of the guidelines adopt extrapolation widely such as 45 Hz to 400 Hz and 7 kHz to 100 kHz. Therefore, determination of threshold value among extrapolated frequencies is important for verification and improving of the current basic restriction. Here, we report progress of our study to determine threshold value of nerve stimulation by magnetic or electric field in in vitro.

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