• Journal of Korean Society of Transportation
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• v.26 no.2
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• pp.121-133
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• 2008

Conventional car following models are controlled when the velocity of following vehicle is equal to preceding vehicle without consideration of relative distance. Also, since the car following models are hardly consider the driver's behaviors and the environmental factors in driving, the models can't be adopted in reality. Hence, we developed the car following model applying Human Factors to consider driver's safety and comfortness. We simulated to compare the suggested model with the existing model, GGM(General GM). As results of simulations, the GGM model followed the preceding vehicle when the velocity of following vehicle was equal to preceding vehicle without relation of relative range. The other side, when the relative range was less or over than safety range, the suggested model made the relative range equal to safety range. Accordingly, we could be sure that the model would decrease the driver's discomfort and intensify the safety on driving without unnecessary waste of road. We identified that the suggested model is more realistic than the conventional GGM model.

• Journal of Korean Society of Transportation
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• v.29 no.6
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• pp.67-74
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• 2011

This study deals with the traffic accidents data from the Korean rotaries (circular intersections) to verify their characteristics affected by different vehicle types. This paper categorized the data into three groups based on vehicle types, and developed a set of accident models. The paper proposed two ZIP models and one negative binomial model through a statistical analysis for three vehicle types: automobile, truck and van, and others. The differences among those models were then statistically compared.

• Journal of Korean Society of Transportation
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• v.17 no.1
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• pp.75-89
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• 1999

위험물차량사고는 일반차량의 교통사고시 발생하는 인명피해, 재산피해, 교통지체 외에 부가적으로 환경적 영향에 의한 엄청난 인명 및 재산손실을 유발시킬 수 있다. 따라서 이러한 위험물차량사고를 예방하고 피해를 최소로 줄이기 위해서는 위험물수송경로의 신중하고 체계적인 결정이 필수적이라 할 수 있다. 따라서, 본 연구는 위험물차량의 수송경로를 결정할 때 고려해야 할 여러 가지의 기준 및 목표에 따라 위험물수송경로를 설정하는 모형을 제시함으로써 위험물수송에 수반되는 위험을 최소화하면서 위험물차량의 통행시간, 거리, 비용 등을 최적화하여 위험물수송의 안전 및 운영효율성을 향상시키고자 한다. 먼저, 위험물 수송경로의 기준지표로 사용될 위험도를 나타내기 위해 사고율과 피해가능규모를 구하도록 사 고건수, 링크 주변노출인구, 링크상의 노출인구, 밀도 등을 변수로 하는 모형식을 제안하고, 두 번째로 위험물 수송을 위한 최적경로를 산출하기 위해 위험도와 통행시간을 목적함수로 하는 다목적계획모형을 제안하였고 기존의 최적경로 알고리즘을 적용하여 최적경로를 산출하였다. 마지막으로 실제 수도권지역을 대상으로 본 연구에서 제안한 모형을 적용하고 현재 일반적으로 사용되는 최단경로와 비교.분석하였다. 모형적용결과, 링크주변인구만을 고려하는 기존 모형에 비해 링크상의 인구를 함께 고려함으로써 좀더 실제적으로 교통상황을 충분히 반영한 피해규모를 산정하였다. 또한, 본 연구에서 제안한 위험도와 통행시간에 0.5의 비중을 주는 다목적모형이 기존의 위험도모형에 비해 충분한 안전성을 확보하면서 최소 4%, 최대 12%의 통행시간 개선의 효과가 있음을 나타냈다.

• Journal of Korean Society of Transportation
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• v.25 no.2 s.95
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• pp.109-120
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• 2007

This study developed a methodology that can reflect more realistic traffic flow to understand platoons on highways. The understanding of the phenomenon nay secure highway safety and authoritative credibility in highway planning. In this study platoons generated by 'random effects' of cars are modeled, and this model is validated using a real data set acquired from the Jayu Expressway in Kyonggi Province, Korea.

• Proceedings of the KAIS Fall Conference
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• 2005.05a
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• pp.48-50
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• 2005

본 연구에서는 차량 충돌 시험시 결과에 관하여 측정하는 방법 중 인체 상해 기준에 따른 평가를 지원해주기 위한 시스템에 관한 것이다. 차량 충돌시험의 가장 큰 분류인 정면 충돌과 측면충돌 2가지에 대찬 내용을 기준으로 인체 모형 각 부분의 결과 값에 따른 기준과 계산 방법 및 법규 규정을 제시하여 준다. 이러한 시스템은 인체 모형의 구성과 차량 충돌 시험시 중요시하는 인체 부분에 대한 이해를 돕는다 실제 인간의 대신한 인체 모형의 이해는 실제 인간이 승차하고 있는 차량의 안전도의 이해를 돕는다. 본 연구에서는 차량 충돌 시험 평가와 인체 상해 기준에 대해 차량충돌 안전부문 관련자들에게 온라인으로 이용할 수 있는 정보지원시스템에 대하여 기술하였다.

• Journal of Korean Society of Transportation
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• v.32 no.3
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• pp.280-292
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• 2014

A tram has been the focus of a new public transportation that can solve a traffic jam, decreasing of public transit usage and environmental problem in recent years. This study aims to develop a signal optimization model for considering the traffic signal progression of tram and vehicles, when they are operated simultaneously in the same signalized intersections. This research developed the KS-SIGNAL-Tram model to obtain a minimum tram bandwidth and to minimize a vehicle's delay to perform a tram passive signal priority, it is based on the KS-SIGNAL model and is added to the properties of a tram and it's system. We conducted a micro simulation test to evaluate the KS-SIGNAL-Tram model, it showed that the developed optimization model is effective to prevent a tram's stop on intersection, to reduce a tram's travel time and vehicle's delay.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.3
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• pp.53-64
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• 2013

The car-following model is one of core models in Advanced Vehicle & Highway Systems (AVHS). The car-following model has been developed in aspects such as human factor and reduction error rates. However, the consideration of safety depending on weather condition has not been completed yet. In this paper, therefore, changes of driving condition for car-following due to different road condition were dealt with, and optimal safety distance corresponding to road condition such as dry, wet and snowy were computed. The GMIT(GM Model with Instantaneous T) model was picked over for simulation of adaptive cruise control applied the suggested optimal safety distance. As the results, the 1.7 times longer safety distance was required for wet road condition than dry road condition, and the 5.6 times longer safety distance was required for snowy road condition.

• Journal of Korean Society of Transportation
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• v.29 no.5
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• pp.107-120
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• 2011

Traffic signal is one of the major factors that affect the amount of vehicle emissions on urban highway. The amount of vehicle emissions in urban area is highly affected by the vehicle's cruising speeds heavily influenced by the traffic signal lighting conditions. It was attempted in this study to trace the changing patterns of the vehicle emissions by collecting the emission data from a set of simulation studies and by categorizing vehicle cruising conditions into four different groups: idling, acceleration, deceleration, and running at a constant speed. Authors propose a simple emission model prepared based on Kinematic theory. The validation test results showed that the amount of the emission estimated by the proposed model was relatively satisfactory compared to the one of the existing model employing the average speed data only as the determinant.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.4
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• pp.693-702
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• 2002

The aim of this study is to develop a 3-dimensional dynamic analysis model, capable of considering the interaction between vehicles and bridges more accurately. The dynamic analysis model is developed with the high-speed train (KTX) and a 2-span continuous prestressed concrete box girder bridge with a double track. The 20-car model is developed using the moving vehicle model for the regular trainset. Three-dimensional frame elements are used for the bridge model. Using the developed models, a dynamic behavior analysis program is coded. The analytical results are compared with the dynamic field test results and found to be valid to yield quite accurate dynamic responses. Based on the results of this study, the hybrid model, made up of the moving vehicle model for the heaviest power car and the moving force model for the other cars, is quite simple and effective without loosing the accuracy that much. Under the coincidence condition of two trains traveling with resonance velocity in the opposite directions, it is necessary to check not only the dynamic responses of the bridge with one-way traffic but those with two- way coincidence.

• Journal of Korean Society of Transportation
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• v.29 no.3
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• pp.73-82
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• 2011

Recent advancement in traffic surveillance systems has allowed the researchers to obtain more detailed vehicular movement such as individual vehicle trajectory data. Understanding the characteristics of interactions between leading and following vehicles in the traffic flow stream is a backbone for designing and evaluating more sophisticated traffic and vehicle control strategies. This study proposes a methodology for estimating rear-end crash potential, as a probabilistic measure, in real-time based on the analysis of vehicular movements. The methodology presented in this study consists of three components. The first predicts vehicle position and speed every second using a Kalman filtering technique. The second estimates the probability for the vehicle's trajectory to belong to either 'changing lane' or 'going straight'. A binary logistic regression (BLR) is used to model the lane-changing decision of the subject vehicle. The other component calculates crash probability by employing an exponential decay function that uses time-to-collision (TTC) between the subject vehicle and the front vehicle. The result of this study is expected to be adapted in developing traffic control and information systems, in particular, for crash prevention.