저탄소 녹색성장 기본법에서 명시한 ‘대중교통과 자전거 이용 활성화’를 위하여, 국내 여러 지자체에서 공공자전거 사업을 시행하였 으며, 자전거 이용자 수가 많이 증가하였다. 현재 국내에서 규정하는 자전거의 통행방식은 간접좌회전(hook turn) 방식으로, 증가된 자 전거교통량이 횡단보도를 통해 좌회전 통행 시 상충 가능성이 증가할 수 있다. 또한 자율주행차량의 혼재교통상황을 고려하여, 자전거 가 차량과 함께 통행할 시 안전성을 보장받을 수 있는지 혼재교통류에 적합한 통행방식을 연구할 필요가 있다. 따라서 본 연구에서는 혼재교통환경에서 자전거 이용자가 안전하고 운영성 높은 방식으로 통행할 수 있도록 4가지 자전거 좌회전 통행방식을 적용하고, 자 율주행차량 점유율에 따른 적합한 통행방식을 제시하고자 한다. Hook-turn 방식을 기본 시나리오로 하여, 자전거 우선 신호를 도입한 bike box, 일반 bike box, 자전거 전용 신호를 도입한 narrow lane 시나리오를 비교하였다. bike box의 크기가 분석 결과에 큰 영향을 미 치는 요인이 될 수 있으므로, 5m 폭의 크기로 고정하였다. 시뮬레이션 환경에서 첨두시와 비 첨두시 교통량을 적용하여 분석하였으며, 안전성 평가지표로 CPI(Crash Potential Index)과 운영성 평가지표로 지체시간(Delay time)을 활용하여 결과를 비교하였다. hook turn시나 리오는 사고 발생 위험도가 작으며, 자전거 전용 신호가 적용된 narrow lane과 일반 bike box에서 사고 발생 위험도가 높게 나타났다. 또한 자전거 전용 신호를 적용한 bike box를 도입한 시나리오에서 운영성 측면에서 지체가 작게 나타났으며, 자율주행차량 점유율이 증가할 시 차간거리를 고려함에 따라 교통류 안전성도 향상되는 것으로 나타났다. 향후 자율주행차량 혼재 교통류를 고려하여 자전거 좌회전 통행방식을 자전거 우선 신호를 적용한 bike box 방식으로 규정한다면, 접근로별 50대 미만/시의 자전거 교통량이 관측되는 신 호교차로에서 안전성과 운영성이 향상되는 효과를 확인할 수 있다.

PURPOSES : This study is to initiated to estimate the impact of mixed traffic flow on expressway section according to the market penetration rate(MPR) of automated vehicles(AVs) using a enhanced intelligent driver model(EIDM). METHODS : To this end, microscopic traffic simulation and EIDM were used to implement mixed traffic flow on basic expressway section and simulation network was calibrated to understand the change of impact in mixed traffic flow due to the MPR of AVs. Additionally, MOEs of mobility aspects such as average speed and travel time were extracted and analyzed. RESULTS : The result of the impact of mobility MOEs by MPR and level of service indicated that 100% MPR of AVs normally affect positive impact on expressway at all level of service. However, it was analyzed that improvements in the level of service from LOS A to C are minimal until the MPR of AVs reaches 75% or higher. CONCLUSIONS : This research shows that impact of MPR of AVs using EIDM of mixed traffic flow on basic expressway. Increasing MPR of AVs affects positive impact on expressway at all level of services. However, MPR from 25% to 75% of AVs in LOS A to C shows minimal impacts. Therefore, to maximize the effectiveness of AVs, appropriate traffic operation and management strategies are necessary.

PURPOSES : Because a driving simulator typically focuses on analyzing a driver’s driving behavior, it is difficult to analyze the effect on the overall traffic flow. In contrast, traffic simulation can analyze traffic flow, that is, the interaction between vehicles; however, it has limitations in describing a driver’s driving behavior. Therefore, a method for integrating the simulator and traffic simulation was proposed. Information that could be controlled through driving experiments was used, and only the lane-change distance was considered so that a more natural driving behavior could be described in the traffic flow. METHODS : The simulated connection method proposed in this study was implemented under the assumption of specific traffic conditions. The driver’s lane-changing behavior (lane-changing distance, deceleration, and steering wheel) due to the occurrence of road debris was collected through a driving study. The lane-change distance was input as a parameter for the traffic simulation. Driving behavior and safety were compared between the basic traffic simulation setting, in which the driver's driving behavior information was not reflected, and the situation in which the driving simulator and traffic simulation were integrated. RESULTS : The number of conflicts between the traffic simulation default settings (Case 1) and the situation in which the driving simulator and traffic simulation were integrated (Case 2) was determined and compared for each analysis. The analysis revealed that the number of conflicts varied based on the level of service and road alignment of the analysis section. In addition, a statistical analysis was performed to verify the differences between the scenarios. There was a significant difference in the number of conflicts based on the level of service and road alignment. When analyzing a traffic simulation, it is necessary to replicate the driving behavior of the actual driver. CONCLUSIONS : We proposed an integration plan between the driving simulator and traffic simulation. This information can be used as fundamental data for the advancement of simulation integration methods.

최근 고속도로 터널부 대형사고의 발생으로 사회적 관심이 급증하고 있다. 고속도로의 터널부는 일반부와는 다른 터널부만의 주행특성을 가지고 있으며, 이에 따라 차량 주행시 고속도로 일반부와 터널부의 속도차이가 발생하게 된다. 이와 같은 현상은 터널 구간이 운전자의 차량 간 거리 감지능력과 급격한 명암 변화에 의해 암순응과 명순응의 시간이 일반구간과 달리 길기 때문에 발생하는 운전자의 자기방어 성격이라 할 수 있다. 이처럼 고속도로 터널부의 경우 고속도로 시설 중 사고에 가장 취약한 구간이라 할 수 있으며 이러한 구간에서의 속도의 변화는 대형 사고로 이어질 가능성이 크다. 본 연구의 목적은 터널 내 설치된 VDS 데이터 자료(속도, 교통량, 점유율)를 활용하여 터널 내 사고 발생시의 기존 대처방안을 보완하고, 터널 이전 지점의 교통량, 점유율 패턴을 통해 터널 내 사고 발생 가능성을 예측하며 사전에 터널 내 소통상황을 향상시키는 방안을 제시하는것이다. 이를 위해 본 연구에서는 각 터널 내 속도패턴, 터널 이전 지점의 교통량 , 점유율 패턴 등을 분석하고, 해당 패턴에서의 사고 발생 가능성을 파악하는 등 터널 부 사고시 신속한 대처 방안 및 터널 내 소통향상 기법 등을 제시한다.

PURPOSES: This study analyzed the lane-by-lane traffic flow characteristics in Korea by using real-world data, including congestion levels, for 2-, 3-, and 4-lane freeways. METHODS : On the basis of a literature review, lane flow and speed characteristics were analyzed using flow measurements and speed ratios. In addition, the effect of congestion levels on traffic flow were visualized using rescaled cumulative plots. RESULTS: Driver behavior varied depending on the congestion level. During free-flow conditions, the lane-use ratio of individual lanes varied largely, whereas during congestion, the ratio was nearly the same for all lanes (i.e., equilibrium). During maximum-flow and congestion conditions, the median lane was used more than the shoulder lane, whereas during all other conditions, the shoulder lane had a higher lane-use ratio. In 3- or 4-lane freeways, the lane-use ratio of the median lane always exceeded 1 and was the highest during free-flow conditions. CONCLUSIONS : The results of the present analysis can be used as an index to predict congestion before a lane is overcapacitated. Moreover, the results can be applied in variable lane guidance systems, such as car navigation systems and variable message displays, to control traffic flow.

PURPOSES: The purpose of this study is to develop a methodology for estimating additional carbon emissions due to freeway incidents. METHODS : As our country grows, our highway policy has mainly neglected the environmental and social sectors. However, with the formation of a national green growth keynote and an increase in the number of people interested in environmental and social issues, problems related to social issues, such as traffic accidents and congestion, and environmental issues, such as the impact of air pollution caused by exhaust gases that are emitted from highway vehicles, are beginning to be discussed. Accordingly, studies have been conducted on a variety of environmental aspects in the field of road transport, and for the quantitative calculation of greenhouse gas emissions, using various methods. However, in order to observe the effects of carbon emissions, microscopic simulations must use many difficult variables such as cost, analysis time, and ease of analysis process. In this study, additional greenhouse gas emissions that occur because of highway traffic accidents were classified by type (incident handling time, number of lanes blocked, freeway level of service), and the annual additional emissions based on incidents were calculated. According to the results, congestion length and emissions tend to increase with an increase in incident clearance time, number of occupied lanes, and worsening level of service. Using this data, we analyzed accident data on the Gyeong-bu Expressway (Yang-Jae IC - Osan IC) for a year. RESULTS : Additional greenhouse gas emissions that occur because of highway traffic accidents were classified by type (incident handling time, number of lanes blocked, freeway level of service) and annual additional emissions caused by accidents were calculated. CONCLUSIONS: In this study, a methodology for estimating carbon emissions due to freeway incidents was developed that incorporates macroscopic flow models. The results of the study are organized in the form of a look-Up table that calculates carbon emissions rather easily.