• Journal of Korean Society of Transportation
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• v.26 no.5
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• pp.91-100
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• 2008

Pedestrians are exposed to accidents as a result of the lack of understanding the meaning of a flashing green signal. This study was to designed to relate changes of pedestrians' crossing characteristics as a functions of flashing green signal timings. A field survey was conducted to collect pedestrian preference and safety and it was examined by signal operation experiment. Two versions of new pedestrian signal timings were compared to the existing pedestrian signal timings. The results indicated that the number of pedestrians who starts to cross during flashing green signals was significantly decreased when flashing green signals started at 1/2 or 2/3 point of crossing. However, the number of pedestrians who remain in the crossing during red signals was significantly increased when flashing green signals started at 2/3 point of crossing. This study concludes that starting flashing green signals at 1/2 point of crossing is the safest. Also, implication and directions for its practical relevance were discussed.

• Journal of Korean Society of Transportation
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• v.19 no.3
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• pp.7-18
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• 2001

The pedestrian signal systems operating presently could provide more time for the pedestrian to cross the street than the previous system, but it would increase the cycle length and cause longer delays at the signalized intersections. For instance, more than 80% of traffic signals would have to have the cycle length increased by 10sec in Daegu Metropolitan areas. Therefore. the purpose of this study is to propose a pedestrian traffic signal time that not only maintains the safety of the pedestrian but also reduces the traffic cycle length. The proposed pedestrian signal time is set to enable enough time for the elderly to cross and the flashing time is set low enough to deter the ordinary person. This new pedestrian signal time can reduce the traffic cycle length at intersections and prevent the Pedestrian crossing during flashing time. In addition to the flashing green should be changed to flashing red to warn the pedestrian he should not begin crossing as opposed to the flashing green which suggest he could cross. In this study, the speed of 1.1m/sec and 0.85m/sec are applied to the new proposed signal time for normal and elderly person respectively after analyzing data collected at Daegu Metropolitan area.

• Journal of Digital Convergence
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• v.14 no.11
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• pp.241-247
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• 2016

As a domestic traffic control signal system, either the system with which a traffic signal turns into green at regular intervals or the system with which an amber or a red signal flickers on local roads without heavy traffic at midnight has been utilized. However, when the former system is used for roads with light traffic at midnight, delays and congestion can be incurred. Besides, in case of the latter signal system, the risk of vehicle crash is high. This study proposes a response type of flickering green signal system that rearranges signal system after analyzing beacon messages including sensor data. The proposed system, on a trunk road or a branch road at midnight, makes the signal keep flickering in green; When a vehicle enters the range of RSE, the transfer coverage, it transmits beacon messages regularly and Agent System analyzes the messages and alters the signal. It is a system by which vehicles move following the altered signal system, which will not only ensure smooth flow but also prevent vehicles from crashing on a road with light traffic. As a result of a simulation, traffic throughput and the average waiting time displayed 10 to 30 percent better improvement than existing signal systems, in terms of performance.

• Journal of Korean Society of Transportation
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• v.24 no.4 s.90
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• pp.43-53
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• 2006

Pedestrian countdown signals were newly introduced to make Pedestrians feel more comfortable and safer in crossing the streets This Paper analysed pedestrian walking-speed through a before-after behavior study Data was collected from 22 sites. and the total number of pedestrians was 19,800. The results showed that the average Pedestrian walking-speed of existing pedestrian signal, an inverted triangle countdown signal and a numeric countdown signal were 1.44, 1.39 and 1.42m/sec. The difference between the three methods was statistically significant. The results showed that the distribution of the walking-speed of existing signal. an inverted triangle countdown signal and a numeric countdown signal were statistically Erlang(0.117, 10) distribution. Weibull(1.17, 3.72) distribution and Gamma(0.137, 8.18) distribution at 95% confidence level.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.296-301
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• 2020

Three types of traffic signal systems are two-color signal systems that flash red and green and are mainly used on crosswalks, next, three-color equalization systems mainly used at T-shaped intersections with red and yellow lights and a green arrow, and third, four-color intersections that generally have red, yellow and green colored lights and a green arrow. In what is known as the "dilemma zone" area, a driver collects information that influences his/her decision whether to stop, speed, tail, interrupt, or violate a traffic light, depending on the intersection width, vehicle speed, cognitive response time and reference yellow signal time. This study examined the impact of changes in the length of the dilemma zone areas based on changes in yellow signal times, the speed of the intersection passages, and signal lamps. Downward adjustments of 50km/h and 60km/h affected yellow signal time. The yellow signal time increased by 0.1 to 2.3[s] due to this effect and the dilemma zone area increased by 1.22 to 26[m]. The driver of the dilemma zone could quickly decide to reduce the time remaining of the straight (3color, 4color) green signal to reduce the potential of a traffic accident at the intersection traffic. Safe entry of red (LED palm) and left-turn signals for entering flashed at the intersection and operated at midnight.

• Journal of Satellite, Information and Communications
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• v.7 no.3
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• pp.145-148
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• 2012

In applying LCD to TV application, one of the most significant factors to be improved is image sticking on the moving picture. LCD is different from CRT in the sense that it's continuous passive device, which holds images in entire frame period, while impulse type device generate image in very short time. To reduce image sticking problem related to hold typedisplay mode, we made an experiment to drive TN-LCD like CRT. We made articulate images by turn on-off backlight, and we realized the ratio of Back Light on-off time by counting between on time and off time for video signal input during 1 frame (16.7ms). Conventional CCFL (cold cathode fluorescent lamp) cannot follow fast on-off speed, so we evaluated new fluorescent substances of light source to improve residual light characteristic of CCFL. We realized articulate image generation similar to CRT by CCFL blinking drive and TN-LCD overdriving. As a result, reduced image sticking phenomenon was validated by naked eye and response time measurement.

• Journal of Korean Society of Transportation
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• v.24 no.5 s.91
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• pp.57-66
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• 2006

This paper presents new pedestrian signal timings considering pedestrian demand Pedestrian characteristics, and land use which were obtained by Pedestrian characteristics field survey and pedestrian signal operation survey. Pedestrian signal timings suggested were compared to the existing pedestrian signal timings by using real field data. pedestrian characteristics field survey was conducted to collect pedestrian crossing speed data and reaction time data. Sixteen areas in Seoul were selected for the data collection. The average pedestrian crossing speed was 1.30m/sec and the 15th Percentile speed was 1.11m/sec. The average reaction time was 2.24 seconds. Pedestrian crossing speed differs by land use, road width. pedestrian age, sex, and number of Pedestrians. Reaction time also differs by road width, pedestrian age, and number of pedestrians. Statistical testing was performed to secure reliability of the collected data.