• Journal of Korean Society of Transportation
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• v.26 no.1
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• pp.79-88
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• 2008

VMS based dispersion of traffic flows enables to decrease delay and congestion. Such being the case, there has been growing interests in VMS operation strategy. The strategy is based on driver's behavior or diversion rate. However, it was not easy to obtain each in practice. The diversion rate, thus far, was investigated by stated preference analysis or simulators. As an alternative, in this paper, a new method to obtain diversion flow rate was suggested using the toll collection system and freeway traffic management system data. A large gap of diversion rate between stated preference analysis and field survey was observed. Out of surveyed 8 tollgate data, the diversion rate was about 7% and was quite lower compared with that of 21%${\sim}$87% from stated preference analysis or simulators. With this at hand, a more careful information provision strategy should be devised and employed to correctly account this kind of differences.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.5
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• pp.138-150
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• 2020

Pedestrians are the most vulnerable road users. According to one analysis of traffic accidents over a five year period, pedestrians accounted for about 40% of all road traffic deaths in South Korea. Although some policy and engineering approaches have been taken to reduce and prevent traffic accidents, the annual accident change rate is -0.7%, which is insufficient. This study verifies the effectiveness of presenting visual messages to pedestrians and the effect from adding auditory messages to the visual messages. The experiment was conducted on crosswalks adjacent to an intersection, and safety behaviors were recorded for a total of 898 pedestrians and considered sufficient. As a result of the study, overall pedestrian safety behavior improved when both visual and auditory messages were presented, rather than just visual messages. Therefore, the results indicate it is more effective to provide a mixed visual/auditory form of messages, rather than providing single stimulus messages.

• Journal of Digital Convergence
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• v.15 no.11
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• pp.77-83
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• 2017

The Korea Expressway Corporation announced that road casualties on expressways in 2016 were 262 deaths, a 24% decrease compared to 343 deaths in 2015, thanks to the expansion of rest areas for sleepy drivers. And the installation of large-sized banners containing strong messages such as "dozing while driving means your death" helped to reduce the casualty caused by driving while drowsy by 35% compared to that in 2015. Accordingly, this study tried to analyze the impact of public advertisements designed to prohibit dozing while driving on expressways upon drivers, and to present a direction for improvement of such public advertisements in the future. Based on case studies and library researches, the study contemplated the effects of public advertisements on expressways at home and abroad. It was confirmed that the accident rate has been higher on straight roads than on curved roads and that the framing of negative messages using provocative images or slogans on traffic accidents has been considerably effective. In conclusion, if the installation of outdoor billboards for public advertisements at rest areas for sleepy drivers is institutionalized and the systematic provision of information by road section inside and outside of vehicles via Variable Message Sign (VMS) services on expressways, outdoor billboards, or navigation services (including smartphones) is available, it would be possible to maximize the effect of the public advertisements.

• Journal of Korean Society of Transportation
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• v.17 no.1
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• pp.91-102
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• 1999

The objective of this study is to evaluate traffic management strategies using Variable Message Signs(MCS) on urban freeways. It is well known that real-time information on traffic conditions increases driver's comfort, and reduces the risks of accidents if drivers are aware of the traffic situation in advance, they decide whether to divert from the freeway or continue on the planned route. The experimental data collected on the Olympic highway we have shown the following results : 1. when the information on both the congested freeway and uncontested diversion route is displayed on the variable message sign. an additional 1.7 percent of traffic diverted, which results in a 3.7 percent reduction in total travel time. 2 Compared with one Proposed VMS message of 'reduce the speed', the other Proposed VMS message of 'keep speed 70km/h' is found to be much more effective in reducing mean speed.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.6
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• pp.54-67
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• 2013

The main purpose of this study is to analyze the diversion rate by the levels of delay and the types of display. For this study, we developed the logit model by analyzing the result of SP survey of drivers who have driver's licence after manipulating a virtual driving simulator. The result of analysis was that the types of display was not statistically significant to the diversion rate. On the other hand, the levels of delay was very meaningful factor with the diversion rate. When the main road was flowing smoothly, drivers started to detour at the levels of delay 125% under the traffic free flow state. Similarly, when the levels of delay got worse, the diversion rate kept the same percentage as it was at the levels of delay 125% state which represented a smooth road condition. Likewise, when the main road's traffic flow was slow, drivers appeared to make detours at the same state of the levels of delay 125%. It was found that as the levels of delay got worse, the diversion rose higher than the diversion rate at the condition of slow traffic flow situation with the levels of delay 125%. The result of this study suggests the criterion of drivers detour point. For the conclusion, the result of study would be a reasonable reference for establishing transportation strategies by reflecting drivers' detouring property and would improve the efficiency of traffic flow.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.6
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• pp.53-62
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• 2011

Although the demand of Variable Message Sign(VMS) has become pervasive in fulfilling the ITS policy, there are still several unsolved problematic issues. The most critical ones of them are inequality and inefficiency of providing traffic information. This paper proposes the Infra-free Variable Message Sign in order to provide useful informations such as road condition, weather, and traffic of the area, where constructing the infrastructure of communication and power supply is relatively very hard. First of all, the characteristics of infra-free Variable Message Sign are studied and analyzed in deep because of differences between normal Variable Message Sign and Infra-free Variable Message Sign in the configuration and the operating method due to the nature of the Infra-free Variable Message Sign. Futhermore, for effective power management of operating Infra-free Variable Message Sign with limited power acquired through stand-alone PV system, new battery connection structure and dynamically variable power managements for the differently shown messages on Variable Message Sign are proposed. The proposed structure in this paper can be applied to not only power management for Infra-free Variable Message Sign but also power management for the various applications using parallel connection battery system.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.4
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• pp.34-50
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• 2012

This study set out to define a communication environment between an ITS center and field device required to be introduced in the nation in order to guarantee the interoperability, compatibility, and global competitiveness of communication between them in the nation. It also aimed to establish technical and policy plans for its introduction, develop an emulator for information exchange, and apply VMS by way of showing an example, thus testing its validity. First, a standard environment for information exchange between an ITS center and field device required to be introduced in the nation was defined as a dual protocol between DATEX and SNMP. The study also proposed a message definition system including meta-attribution definition and OID introduction. The study then suggested technical and policy plans for its introduction including securing enough feasibility with feedback through a model project of standard introduction, offering education and promotions for the standard in advance, providing methods to introduce and systematically manage OID, developing a hardware standard proper for the information exchange standard, and setting up an integrated management system to introduce a dual protocol.