JSTE Journal of Traffic Engineering
Online ISSN : 2187-2929
ISSN-L : 2187-2929
Volume 2 , Issue 2
Special Edition
Showing 1-29 articles out of 29 articles from the selected issue
Special Edition A (Research Paper)
  • Toru SEO, Takahiko KUSAKABE, Yasuo ASAKURA
    2016 Volume 2 Issue 2 Pages A_1-A_10
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    A fundamental diagram (FD), also known as flow–density relation, is one of the most important concepts in traffic flow theory. It would be valuable if an FD could be estimated by GPS-equipped probe vehicles;because they can collect data from wide spatiotemporal area, compared to traditional fixed sensors. This paper proposes methodology for estimating an FD based on trajectories of sampled vehicles. The proposed methodology estimates values of a free-flow speed and a critical density of a triangular FD, while it exogenously assumes FD's functional form and a value of its jam density. In order to validate the proposed methodology, an algorithm for estimating FD parameters is developed. The algorithm is based on the proposed methodology and is designed to heuristically estimate FD parameters from actual traffic data. Then the algorithm was validated based on traffic data generated by microscopic traffic simulation. The results suggested that the proposed methodology can estimate FD parameters fairly accurately and robustly.
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  • Jun SAKAMOTO, Shunichi YAMAOKA, Motohiro FUJITA
    2016 Volume 2 Issue 2 Pages A_11-A_18
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    Many local railway companies, in Japan, have a huge deficit as a result of passenger decrease due to motorization; in addition, some residents are not interested in the railway at all even if their city has a local railway because the railway is already an unusual system for them. On the other hand, such a railway have become an important local public transport system in the era of shrinking; many local cities in Japan has a similar situation. Therefore, if a local government chooses the railway as a main local public transport system, residents’ understanding and support to a local railway is necessary. In this study, the impact of information provision of local railway on residents’consciousness was analyzed. As a result, it was revealed that the information provision of the value of local railway could change residents’ consciousness; the information by mass media could affect residents’ thinking. However, it was clarified that changing the mind of residents, not interested in the issue, was difficult by only these information provisions.
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  • Takahiro YABE, Yoshihide SEKIMOTO, Takehiro KASHIYAMA, Hiroshi KANASUG ...
    2016 Volume 2 Issue 2 Pages A_19-A_27
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    Reducing damage on human society from natural disasters is an urgent matter of many cities and countries all over the world, and especially, preventing people from over-concentrating in urban areas after the disaster is important. Predictions of people movement after disasters can be utilized for making quick rescue plans which can avoid the concentrated areas, efficiently distributing supplies such as water, food and shelter, and preventing further damages caused by over-crowding. In this paper, we present our method of accurately predicting people's movement under disaster situations in a metropolitan scale. Our method combines multi agent simulation using a disaster behavioral model, and real-time observation data using Particle Filter method. We verified the effectiveness of our method by experimenting it on the Great East Japan Earthquake, and obtained a high prediction accuracy. Also, the number of people bound for each destination matched the survey results carried out by a different research, supporting the accuracy of the method.
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  • Hiroko MORI
    2016 Volume 2 Issue 2 Pages A_28-A_36
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    It has been a persistent challenge to reduce the amount of carbon dioxide emissions and conserve energy from automobiles such as fuel-efficient vehicles. On the other hand, an improvement in fuel consumption can be expected depending on the selection of the vehicle type, the driving behavior, and the route. However, it has not been possible to know the change in fuel consumption due to drivers’ choices such as the change in the type of vehicle or in the driving behavior. In this study, we developed a model that could predict fuel consumption by analyzing probe car data. After the analysis, we decided to use the average speed, road grade, car weight, and driving type as structuring parameters and estimated the model formula by a multiple regression analysis. Upon validating the model formula, we found that the correlation coefficient between the predicted and actual fuel consumptions for gasoline engine cars exceeded 0.9, showing an accurate prediction.
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  • Ryota HORIGUCHI, Masao KUWAHARA
    2016 Volume 2 Issue 2 Pages A_37-A_44
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    This paper proposes the method for traffic flow state estimation by only using probe vehicle trajectories. Such method may have an advantage of robustness to the conventional approach requiring any traffic sensors which might be costly to implement and be often impaired in a big disaster scene. The method bases on the variational theory (VT) by Daganzo (2005) but relax it to an optimization approach to minimize the constraint energy functions provided through the given probe trajectories. This relaxation will increase the applicability of VT to the realistic probe trajectories which may not always keep the flow conservation law and the first-in-first-out principle which are the essentials of VT. In the paper, the idea and the formulation of the relaxation of VT are described at first. Then, followed by the conclusion, simple computational experiments to confirm the validity of the traffic flow state estimation by the proposed method are conducted.
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  • Shoki FUJI, Takuya MARUYAMA
    2016 Volume 2 Issue 2 Pages A_45-A_51
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    Existing trip-chain-based user equilibrium assignment can provide only a short-term travel demand forecasting and it cannot provide long-term forecasting. This is because the method assumes the simple short-term direct demand functions and it is not suitable for long-term forecasting. Meanwhile, some practitioners propose a simple method to forecast future master data of Person Trip survey. They make the forecasting by changing expansion factors of current master data considering the distribution of future population. This study integrates these two methods and proposes a simple long-term travel demand forecasting method. This method is trip-chain-based variable demand model considering network congestion consistently. Then, we validate the method by post evaluation using 1997 and 2012 Kumamoto Metropolitan Area Person Trip survey data. Although the method has limitation that it cannot capture the structural changes such as increase of automobile trip by the elderly, we confirm that this method can be applicable easily to long-term travel demand forecasting.
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  • Hidekatsu HAMAOKA, Tomhiro YOSHINAGA, Ryu YOH
    2016 Volume 2 Issue 2 Pages A_52-A_58
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    When road repair is required at the two-lane-two-way expressway, switching control for both directions by utilizing one common lane is often used. This control makes driver unstable situation, therefore, warning to inform the existence of this control is widely shown at the IC or the information board along the expressway by the road management authority. However, this information could not satisfy the driver’s needs fully, because driver would like to know the situation whether he/she could pass the road repair section without stopping or not. By considering this situation, the needs of driver for this situation were analyzed by the survey of driver at the expressway. At the survey, “time table” that driver could understand the moving direction by contrasting the current time at the road repair section was proposed. Result of survey shows that 80% of drivers evaluated this time table useful. Moreover, it is clarified that time table is effective if the time to stop in front of the road repair section is more than 12-13 minutes. These results show the advantages to use time table at the road repair section in the two-lane-two-way expressway.
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  • Noboru ISE
    2016 Volume 2 Issue 2 Pages A_59-A_64
    Published: January 15, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    Recently, the numbers of road traffic accidents, fatalities and injuries have been decreasing in Japan. However, the numbers of them caused by elderly drivers have been increasing, because of current social situations: 1) increasing elderly population and 2) high ratio of driver's license ownership for people over 65. Therefore, some local authorities give some kinds of benefits to elderly people who returned the driver's license, in order to reduce road traffic accidents caused by elderly drivers. On the other hand, it has been clarified some factors to promote to return the driver's license. However, as far as I know, there is no research to analyze characteristics of driver's license holders who intend to return the driver's license by receiving benefits. Therefore, local authorities cannot consider effective benefits to promote to return the driver's license considering area characteristics. This paper mainly aims to clarify the characteristics of driver's license holders who intend to return the driver's license by receiving benefits, in order to obtain fundamental knowledge to consider effective benefits to promote to return the driver's license considering area characteristics.
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  • Yuichiro KANEKO, Yoshiki ASHIDA
    2016 Volume 2 Issue 2 Pages A_65-A_74
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    The object of this study is to analyze alternative transport to the bus during disruption of train operation in Tokyo metropolitan area. It was analyzed on the use trends in bus and the relationship between the number of users and the length of trouble time, bus lines area by using the actual data bus operators owns. In addition, in order to grasp the selection characteristic of another route during disruption of train operation and the presence or absence of use experience of alternative transport to the bus, web questionnaire survey of railway users was conducted. As a result, it was found to be such as the following. If trouble time is long, the bus is utilized regardless of the area, on the other hand, if a trouble time is short, a short distance buses are widely used. That is, the transfer transport to bus was found to play a role during railway operation disrupted.
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  • Masahiro TADA, Katsuhiro IIDA, Makoto NAKANISHI, Sihyoung AN, Norihiro ...
    2016 Volume 2 Issue 2 Pages A_75-A_84
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    In this study, to know elderly drivers hazard perception ability on expressway, we developed a hazard perception test. Based on the statistical analysis result of accident records on expressway in past five years, we selected elderly drivers' accident-prone spots. Then we created traffic scene videos at the spots for hazard perception test using three vehicles to simulate risky traffic conditions frequently occurred at the spots. As a result of experiment with 40 participants (20 elderlies and 20 non-elderlies), we found out that elderlies' hazard perception test scores (corresponding to hazard perception ability) were significantly lower than non-elderlies'. Moreover, we found out that elderlies were not good at (1) predicting surrounding vehicles' movement which could increase collision risk at junctions or toll barriers, (2) predicting change of traffic conditions around while simultaneously paying attention to multiple vehicles around.
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  • Kazuki WATANABE, Hideki Nakamura
    2016 Volume 2 Issue 2 Pages A_85-A_91
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    The gap acceptance behavior to the opposing through traffic of “permitted” right-turn vehicles is one of the important events for evaluating the safety of signalized intersections. In this study, a decision-making process of gap acceptance was carefully investigated through paying attention to a difference by the number of opposing approach lanes. Moreover, a gap acceptance model of permitted right-turn vehicles at the multilane signalized intersection was developed considering arriving vehicles’ positions in the multiple opposing approach lanes by using binomial logit model. The model estimation result quantitatively showed that the gap acceptance decision is being influenced not only by gap times and arrival through vehicle speeds but also by their driving positions at the intersection approach lane. Furthermore, the calculation result of the critical gap time suggested that it varies depending on the positions of opposing through vehicles in the multilane intersection comparing to the case of single opposing lane intersection.
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  • Eri AOYAMA, Tomoyuki INAGAKI, Satoru KOBAYAKAWA , Hirohisa MORITA
    2016 Volume 2 Issue 2 Pages A_92-A_99
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    Bicycle traffic is estimated to be increased. To get fundamental knowledge for considering cycling environment from the point of view of capacity and control, this paper analyzed starting behaviors of bicycle traffic at signalized intersections. To analyze the headways, start-up delay and saturation flow rate, the survey was conducted in ideal condition that has enough traffic demand and uniformized cycling manners. As a result, four facts listed below were found. 1; It is difficult to estimate influences of bicycle’s start-up delay from only characteristics of headways. So bicycle’s start-up delay needs to be studied from a fluctuation of saturation flow rate. 2; Number of bicycles affected by start-up delay is larger than that of cars. 3; Saturation flow rate of bicycle is estimated about 2,900~3,200 bicycles per hour of green, the value is larger than that of car. 4; Starting behavior of bicycle can be affected by highway geometric structures and left-turning cars.
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  • Hiroshi TATSUMI, Kayoko TSUTSUMI, Syuji YOSHIKI, Azusa TSURUMARU
    2016 Volume 2 Issue 2 Pages A_100-A_107
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    Recent years, the local public transportations are introduced by the local government for support the transport behavior of the people who cannot drive a vehicle. However, the actual ridership is often less than the number of passengers assumed in advance. Therefore, the purpose of this study is grasping the user characteristics of the local public transportation, and clarification what kind of people use the local public transportation. The analysis object is the local bus of Chikuzen town in Fukuoka prefecture. First of all, the questionnaire survey for inhabitants was carried out, and the personal attribute and mobility environment of the respondent and the household attribute were analyzed. Next, the relation between those factors and the using of the local public transportation or not and the frequency was analyzed. Furthermore, the demand prediction models using quantification II were built, and the influence that each factor gave to use having the local public transportation or not and frequency was clarified.
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  • Kojiro MASTUO, Yasuhiro MIMURA, Motohiro YAMAZAKI, Koumei KANNO, Mitsu ...
    2016 Volume 2 Issue 2 Pages A_108-A_114
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    Controlling or reducing vehicles’ speeds on community streets have been an important issue in promoting traffic calming. Recently, on the other hand, the concern over intelligent speed adaptation (ISA) has been growing mainly in European countries. Also, the discussions about rewards or penalties for everyday driving speed compliance to reinforce incentives for speed reduction have started. In this study, we analyzed the effects of Advisory ISA and Incentive Program for Not Speeding (IPNS) on driving speed on community streets, based on data from a 5-month field experiment. According to the results, we found that Advisory ISA had a certain effect on speed compliance in Zone 30 areas, that IPNS applied in the field experiment had high speed compliance effects for community streets which also include narrow streets without posted speed limit, and that the speed compliance ratios in Zone 30 areas kept higher even after the release from Advisory ISA and IPNS.
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  • Takayuki KAGAWA, Masashi KUWANO, Kei FUKUYAMA, Keishi TANIMOTO, Takao ...
    2016 Volume 2 Issue 2 Pages A_115-A_124
    Published: February 02, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    Bus-Net, the public transit navigator system developed by Tottori University, has been introduced in Tottori prefecture in Japan. The system has log data that show the users’ future movement plans. This study defines users’origin-destination information stored in the path finding system as their movement desire. The purpose of this study is to grasp the traffic characteristics of Tottori city by using the origin-destination search information in the log data. This study objectively summarizes the origin-destination information with the statistical techniques of principal component analysis since the origin-destination information has a large number of possible combinations of origins and destinations. Moreover, this study finds the day variation and the month variation of each movement desire by using time series analysis. As a result, we detected the traffic characteristics of Tottori city such as the movement desire of commuters in winter when snowing surface freezing affect traffics, and the movement desire of tourists who travel among famous tourist spots and transportation facilities (such as airport and station).
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  • Daiki NISHIHARA, Hiroshi TATSUMI, Syuji YOSHIKI, Kayoko TSUTSUMI
    2016 Volume 2 Issue 2 Pages A_125-A_133
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    The purpose of this paper is to examine the influence of vehicles on cyclist gaze behavior. Driving experiment with eye mark recorder was carried out on the following; a road shoulder 1 meter wide, bicycle lane 1.85 meters, and bicycle lane 2.2 meters. Results show that cyclist gaze behavior varies depending on the bicycle environment. First, a time and the number of times, which research participants gaze at road shoulder, increases as the number of vehicles overtook bicycle increases on the road shoulder 1 meter wide. It is considered that cyclist often determine if they pedal a bicycle on the inside of the road shoulder due to narrow width. Second, saccade is likely to occur as the number of vehicles overtook bicycle increases on the bicycle lane 1.85 meters. Third, vehicles does not have an influence on cyclist gaze behavior on bicycle lane 2.2 meters. These result show that the effect of implement of bicycle lane and width of bicycle environment.
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  • Hirofumi YOTSUTSUJI, Mitsuho MARUYAMA
    2016 Volume 2 Issue 2 Pages A_134-A_143
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    A household member under constrained mobility for a short trip can be supported by getting a ride from other households in community. In such short-trip ridesharing, because it is difficult for drivers to get incentives for splitting the short-trip costs with passengers, one motive for driver candidates to accept passenger candidates is other-regarding preference by which the driver gives the passenger a free ride. In a situation that trip frequencies and head counts of the driver candidates are more than those of the passenger candidates, an issue on operating system of the short-trip rideshares based on one-to-one two-sided matching is sustainability of the system in which altruists participate. The purpose of this paper is twofold. One purpose is to construct a systems analysis model regarding the short-trip rideshares. The other is to analyze the system sustainability through information guidance mechanism. Our simulation results showed that the decrease in the number of rideshare pairs can be suppressed by the information guidance based on messages that induce driver candidates' expectation about the state of ridesharing as the likely success of it.
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  • Makoto KASAI, Shintaro HAYASAKA, Taisuke UTSUMI, Takanori ODA, Shintar ...
    2016 Volume 2 Issue 2 Pages A_144-A_150
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    This study focuses on a relation-ship between velocity and road design for performance oriented road and operational planning for arterial roads. We try to reveal the relation based on production (average flow) and accumulation (average density) in urban area, since it is difficult to measure uniform quality of service (travel speed) of different users' OD. First, a data set by urban area is processed from “Road Traffic Census” produced by MLIT in Japan. The data set contains longitudinal alignment of roads, spatial average speed, average network flow (production) and average network density (accumulation). Second, a multi-regression model, where the spatial mean speed is regarded as an objective variable, is calibrated. Density of signalized intersection is a significant explanative variable as well as traffic density in urban area. Third, a relation between travel speed and the density of signalized intersection is formulated as a performance function. This function will contribute to the performance measurement considering service level of access and egress in an urban area.
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  • Hidetaka MORI, Mamoru TANIGUCHI
    2016 Volume 2 Issue 2 Pages A_151-A_159
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    Low birthrate and longevity is getting serious problem particularly in some local cities. Public transportation which used to take root in the cities also has been declining because of motorization development. On the other hand, it is said that mobility services without using private automobile are needed for the old who are not able to drive automobile now or in near future. In this research, we should analyze that "demand responded services," which have been introduced in some areas, have effects to reduce anxiety in daily life or not. As a result, 1) demand responded services would reduce some of anxiety about transportation and commercial facility in daily life for people, 2) the implement measures to promote the demand responded services should be different widely by who they are and where they live, 3) the companies which operate the demand responded services should intends to phase in the implement measures.
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  • Takaaki OTSUKI, Makoto KASAI, Shintaro TERABE
    2016 Volume 2 Issue 2 Pages A_160-A_165
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    In this paper, traffic flow data just before break-down is collected using driving simulator on two sag sections (gentle and sharp sag) and level course. The traffic flow is expected to have homogeneity since a participant iteratively follows the leader, whose moving is identical to the last recorded data by him or herself. Therefore, relatively weaker sag may be found by comparison in a minimal value of flow rate and a position where the minimal rate is recorded. Findings are as follows; 1) minimal flow rate is recorded at ascent section in case of the both sags, and 2) difference between the two sags are not observed clearly. The result leads the fact that all sags commonly become candidates for bottleneck contrary to the experimental fact that bottleneck phenomena are observed on specific sags. This paper mentions to necessity to examine interaction of adjacent sag sections as a future direction.
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  • Tomoyuki INAGAKI, Shoichiro FUJISAWA, Kazuya TAKAHASHI, Norihiro IKEDA ...
    2016 Volume 2 Issue 2 Pages A_166-A_173
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    For supporting road crossing of the visually impaired, many facilities such as a tactile walking surface indicator, an audible signal and a tactile guiding line on a crosswalk have been introduced in various areas in Japan. Reliability of these facilities or curbs at a boundary between a sidewalk and a carriageway fluctuates greatly with location of a crosswalk. This situation leads to enhance a psychological burden in crossing rather than help. To develop a method to promote more accurate road crossing orientation of the visually impaired, the authors suggested the direction taking blocks mounted around tactile walking surface indicators at an entrance of a crosswalk and conducted the evaluation experiment in the completely blind persons. By analysis based on subjective evaluation by the experiment participants and observation of their walking and direction taking, the best specifications and laying methods of blocks that maximize the effectiveness of support had been extracted.
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  • Katsuhiro IIDA, Yuya KAJIWARA, Hideki TAKAHASHI, Fumihiro ITOSHIMA
    2015 Volume 2 Issue 2 Pages A_174-A_182
    Published: February 05, 2015
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    In Japan in recent years, route information panels indicating graphical symbols have been introduced with an expectation of the improvement of readability. However, it has been pointed out that some graphical symbols among the present ones are not understood correctly by road users. It is possible that these cases cause unsafe driving acts like reducing speed in front of information panels under the driving conditions with limited time for reading panels. First, this research has newly created graphical symbols concerning a fire, accident, and falling object and conducted indoor driving experiments by using driving simulator. Next, this research has comparatively assessed the result of the experiments and confirmed that the readability of information panels was improved when new graphical symbols were indicated. Based on this, it was grasped whether reading information panels causes unsafe driving acts.
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  • Xin ZHANG, Hideki NAKAMURA
    2016 Volume 2 Issue 2 Pages A_183-A_192
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    Timing of pedestrian phase plays an important role in the safety and mobility performance at signalized intersections. In order to evaluate the performance, it is useful to understand effects of crosswalk length and signal timing on pedestrian presence position and timing. This study investigates the effects of elapsed pedestrian green time, waiting time, crosswalk length and pedestrian volume on the spatiotemporal probability of pedestrian presence and models its distributions considering these influencing factors. It was found that pedestrian presence probability distributions shift to the moving direction as pedestrians proceed. The shorter pedestrian waiting time and longer crosswalk length lead to the wider distribution of pedestrian presence probability. In addition, application of the pedestrian presence probability model for setting Leading Pedestrian Interval (LPI) is discussed. Possible ranges of LPI are investigated dependent on crosswalk length, vehicle flow rate and ratio of pedestrian having passed the conflict area according to pedestrian directional rate.
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  • Keiichi HIGUCHI, Yasuhiro MIMURA, Ryosuke ANDO
    2016 Volume 2 Issue 2 Pages A_193-A_198
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    In recent years, the traffic accident has decreased the outbreak number and the casualties. But, it doesn't decrease in community road. Therefore, traffic safety measures of community road have been required to proceed with the town development. Measures of traffic accidents and urban crimes have been pointed out in common, but are separately managed and operated. To examine the measures is highly necessary to clarify the relationship between traffic accidents and crimes. In this study, to clarify the relationship between traffic accidents and urban crime, it was subjected to extraction of area characteristics that have influence in the past number of occurrences. As a result, it was possible to extract area characteristics such as the number of public facilities and residential areas as a factor that influences in common to the incidence of traffic accidents and crimes. These results can be considered to be a basic knowledge in order to promote efficient measures towards the safe and secure town development.
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  • Keiko FUKUMURO, Tetsuhiro ISHIZAKA, Atsushi FUKUDA
    2016 Volume 2 Issue 2 Pages A_199-A_204
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    Recently, in order to evaluate countermeasures toward low carbon transportation system, the conventional method based on average speed is not sufficient to estimate precise fuel consumption based on dynamical running situation. On the other hand, Vehicle Specific Power (VSP) has a possibility to estimate it more precisely than the existing method. The parameter of VSP should be calibrated for showing unique characteristic of each vehicle. Therefore, the objective of this study is to estimate parameter of VSP by carrying out coast-down test. This study estimated the parameters related to the running resistance by the coast-down test. In addition, the VSP was estimated from the running data aggregated with different operating mode. It was concluded that the both interval of aggregation can provide same accuracy.
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  • Katsuhiro IIDA, Ayaki SUZUKI, Kazumi RENGE, Hideki TAKAHASHI, Fumihiro ...
    2016 Volume 2 Issue 2 Pages A_205-A_212
    Published: February 05, 2016
    Released: February 05, 2016
    JOURNALS FREE ACCESS
    Nowadays, symbols are being displayed on variable message sign in expectation of improvement in readability of the message signs. However, it is pointed out that many of present symbols are not comprehended correctly. This study contrived new symbols expressing accidents, fires, fallen objects while taking the frequency and the priority into consideration. And this study set evaluation categories based on a definition of a graphical symbol in ISO. Evaluation categories are “legibility”, “comprehensiveness” and “appropriateness”. And this study compared new symbols and existing symbols by the indoor driving experiment and mentioned suitable graphical symbol for providing road information on with reference to the method of evaluation determined in JIS and ISO. As a result, this study acquired knowledge about suitable symbols for providing road information. For example, symbols expressing accidents which don't have detailed description and express a collision with the high occurrence frequency received high evaluations in terms of “legibility”, “comprehensiveness” and “appropriateness”.
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Special Edition B (Practical Paper)
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