• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.4C
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• pp.276-282
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• 2005

These studies developed system as well as its algorithm which can measure traffic flow and vehicle speed on the highway as well as road by using industrial television(ITV) system. This algorithm used the real time processing of dynamic images. The processing algorithm of dynamic images is developed and proved its validity by frame grabber. Frame grabber can process the information of a small number of sample points only instead of the whole pixel of the images. In the techniques of this algorithm, we made approximate contour of vehicle by allocating sampling points in cross-direction of image, and recognized top of contour of vehicle. Applying these technique, we measured the number of passing vehicles of one lane as well as multilane. Speed of each vehicle is measured by computing the time difference between a pair of sample points on two sample Points lines.

• Journal of Korean Society of Transportation
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• v.18 no.1
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• pp.35-43
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• 2000

The Purpose of this Paper was to study the relationship between the change of operating speeds and the accidents on horizontal curves. For this purpose, we divided a horizontal curve section into two parts, a tangent section and a curve section, to estimate the operating speed for each vehicle. For studying relationship between the change of speed and geometric effect, the free-flow speed was used. The location and speed for the lowest speed were studied. Also, we analyzed the relationship between the change of operating speeds and the accidents. The followings are resulted in this study. First, drivers tend to reduce speeds significantly before they reach a curve. And the lowest speed was recorded at the downstream of the Point of curve (PC) due to the limited sight-distance of drivers on curve. Second, the larger the change of operating speeds become, the greater frequency of accident was recorded. These results can be used for developing the safety index on highways to check the design consistency.

• Journal of the Korean Institute of Gas
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• v.12 no.1
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• pp.13-18
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• 2008

Vibration velocity induced by earthquakes or external vibration sources is one of the integrity assessment indexes, and is also a representative value used to describe the amount of vibration because it is based on a proportional relationship with the damage scale. In this study, the vibration velocity criterion for structures is first examined. Then, based on the velocity criterion, an integrity assessment is performed. Burial condition is set up based on the "Highway and Local Road Design Criteria" with API 5L Gr. X65 pipeline(D=762 mm). The FE model considers DB-24 vehicle load as a time function with a varying velocity in the range of $20{\sim}160\;km/h$. Maximum vibration velocity occurs at v=80 km/h and decreases after v=80 km/h. The maximum vibration velocity of buried pipeline by DB-24 loads is about 0.034 cm/s. The velocity that occurs is in the range of allowable values for each vibration velocity criterion. The wave propagation velocity was identified based on attenuation law and the minimum value appears at vehicle velocity 80 km/h that has maximum vibration velocity.

• Journal of Korea Society of Industrial Information Systems
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• v.19 no.5
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• pp.69-79
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• 2014

This paper proposes the Collision Prevention System based on Fuzzy which reasons a risk with the location information of vehicles and pedestrians and prevents collision between vehicles, and between a vehicle and a pedestrian with the reasoned risk. The proposed system provides three functions. First, it identifies a pedestrian's location with his smart phone and a vehicle's location with the GPS equipped in the vehicle. and transfers the identified information to their neighbors. Second, it makes a vehicle and a pedestrian reason a risk by considering a moving direction, a moving speed and road information. Third, it provides a vehicle and a pedestrian with the reasoned information such as route detour, speed reduction, etc. Therefore, the proposed collision prevention system based on Fuzzy not only prevents collision accidents beforehand by reasoning a risk, but also reduces a variety of losses by protecting traffic accident and congestion.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2008.04a
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• pp.381-384
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• 2008

요즈음 교통사고를 줄이기 위하여 IT 기술을 이용한 교통사고 연구가 많이 진행되고 있다. 그러나, 뺑소니 교통사고 발생하면 가해차량을 현장에서 찾기가 매우 어렵다. 본 논문에서는 이러한 문제점을 해결하기위해서 RFID TAG를 이용해서 뺑소니 교통사고가 발생할 경우에 차량에 내장된 RFID 리더기가 상대방 차량의 차량번호를 인식할 수 있는 모의실험을 하였다. 뿐만 아니라, PDA를 이용한 인터넷 기반에서 교통사고가 발생한 경우에 현장에서 운전자가 교통사고현장 자료 및 운전자 인적사항을 경찰서나 보험회사에 전송할 수 있는 SW를 모의실험 하였다. 모의실험결과 통과차량속도가 저속인 경우에는 70%이상 차량번호를 익식할 수 있음을 확인하였다.

• Journal of the Korean Society for Railway
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• v.17 no.5
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• pp.342-348
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• 2014

Contact between wheel and rail leads to the creep phenomenon. Linear creep theory, assuming linear increase in the creep force vs creep, results in a critical speed at which the vibration of a railway vehicle goes to infinity. However, the actual creep force converges to a limited value, so that the vibration of a railway vehicle cannot increase indefinitely. In this study, the dynamics of a railway vehicle is investigated with a 6 DOF bogie model includingthe nonlinear creep curves of Vermeulen, Polach, and a newly calculated creep curve with strip theory. Strip theory considers the profiles of the wheel and rail. The results show that the vibration of a railway vehicle results in a limit-cycle over a specific running speed, and this limit-cycle becomes smaller as the slope of the creep-curve steepens. Moreover, a hunting phenomenon is caused due to flange contact, which restricts the magnitude of the limit-cycle.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.7
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• pp.591-597
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• 2017

This study is to develop a vehicle Integrated Dynamics Control System(IDCB) that can stabilize the lateral dynamics and maintain steerability. To accomplish this task, an eight degree of freedom vehicle model and a nonlinear observer are designed. The IDCB independently controls the brake systems of four wheels with a fuzzy logic control and a sliding model control. The result shows that the nonlinear observer produced satisfactory results. IDCB tracked the reference yaw rate and reduced the body slip angle under all tested conditions. It indicates that the IDCB enhanced lateral stability and preserved steerability.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.6
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• pp.35-41
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• 2010

The ubiquitous-transportation sensor network (u-TSN) system is a next generation transportation system that provides traffic information through analysis and processing periodic information from vehicles. In this paper, we propose the adequate transmission scheme from vehicles for collecting vehicular information. The conventional scheme is transmitting each vehicle information every 0.1s. A variable transmission period scheme is proposed in this paper according to vehicle speed. The proposed and conventional schemes are compared with computer simulations.

• Journal of Korean Society of Transportation
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• v.27 no.3
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• pp.161-168
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• 2009

The ubiquitous transportation system environments make it possible to collect each vehicle's position and velocity data and to perform more sophisticated traffic flow management at individual vehicle or platoon level through V2V and V2I communication. It is necessary to develop a new traffic management paradigm to take advantage of the ubiquitous transportation system environments. This paper proposed a preventive congestion management algorithm for uninterrupted flow, whose goal is to minimize the incident potential and maximize the productivity by maintaining traffic flow stability. The algorithm includes the following steps: Processing the raw data to produce the 3-dimension speed/flow/density profile and to produce the platoon profile and the shock wave profile, Determining the traffic state and the flow stability based on the processed data, Deciding the desirable speed the according the traffic flow state, and finally Providing the desirable speed information. It remains as further work to perform field experiments and calibrate the algorithm parameters.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2008.04a
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• pp.366-369
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• 2008

무선 센서 네트워크(Wireless Sensor Network)는 차세대 IT 기술로서 소형, 저가, 저전력을 필요로 하며, 외부 환경의 모니터링과 제어기능을 수행할 수 있다. 이것은 소형 장치 안에 마이크로프로세서, 각종 센서, 액추에이터, 유 ${\cdot}$ 무선 통신 장치를 내장하는 수백 혹은 수천 개의 센서 노드로 구성된다. 본 논문에서는 이러한 센서 네트워크를 이용하여 기상의 악천 후 속에서 차량 및 도로 상황 정보를 실시간으로 미리 획득하고 분석하여 운전자에게 미리 도로의 안전속도를 통보할 수 있는 실시간 차량 안전속도 서비스 시스템을 설계하고 구현된 결과를 보여 주고자 한다. 본 시스템은 노면의 종류 및 기상 상태 등에 대한 정보를 수집하여 이를 바탕으로 운전자에게 안전 속도를 알려줌으로써 교통사고를 효과적으로 예방할 수 있는 방법을 제공할 수 있다.