This study aims to evaluate traffic safety facilities in school zones in Busan Metropolitan City through Importance-Performance Analysis. This study investigated the traffic safety facilities in nine school zones, which have relatively more traffic accidents in Busan Metropolitan City from 2020 to 2022, through a field study and an Analytic Hierarchy Process(AHP). It identified their performance(i.e., compliance rate) and importance to derive measures for the improvement of traffic safety facilities in school zones. The field study showed that the compliance rate of starting points among traffic safety signs was low, and no speed limits were complied with the installation regulations among traffic road markings, but road safety facilities were generally well managed and operated. As a result of AHP, the order of importance was road safety facilities, traffic safety signs, and traffic road markings. More specifically, speed bumps, safety signs, and crosswalks were found to be more important than others in road safety facilities, traffic safety signs, and traffic road markings, respectively. Importance- Performance(compliance) Analysis revealed that the traffic safety facilities necessary to be most urgently improved are starting points. This result can be resorted to underlying measures to determine priorities for installing and operating traffic safety facilities in school zones.

Autonomous vehicle technology is targeted for commercialization in 2027. However, a mixed traffic environment of conventional vehicles and autonomous vehicles is expected to be inevitable. In mixed traffic, conventional vehicles drive at reduced speeds due to limited visibility, while autonomous vehicles can drive at normal speeds using sensors. The difference in driving speeds between the two vehicles creates a mismatch in traffic flow, and the risk of congestion and accidents is likely to increase. It is necessary to analyze the impact of the interaction between autonomous vehicles and regular vehicles on traffic safety in advance and develop management measures to mitigate it. In this study, we aim to analyze the effect of reducing the speed deviation between general vehicles and autonomous vehicles by providing the driving speed deceleration level information to autonomous vehicles in the event of fog to induce the same traffic flow and improve the safety level accordingly. We examined the method of delivering the driving speed deceleration level information to autonomous vehicles. When providing speed limit information to autonomous vehicles through systems such as VMS, each country has different ways of recognizing regulatory symbols. Due to these differences, it may not be easy to provide regulatory information to overseas vehicles through external systems such as VMS in Korea. For this reason, there is a possibility that autonomous vehicles may violate laws and regulations by not recognizing them properly, and there are still limitations in defining the responsibility for applying laws and regulations between countries. Therefore, we adopted an information provision approach that encourages autonomous vehicles to maintain a harmonious traffic flow with regular vehicles by sharing safe driving speed information to be encouraged at the public center level. To analyze the effectiveness of these safe driving speed management measures, we used a quantitative indicator, the number of observable conflicts, to distinguish the mixing ratio of regular vehicles and autonomous vehicles. The analysis was divided into early (30%), mid (50%), and late (80%) periods of autonomous vehicle introduction. As a result of giving autonomous vehicles the same traffic flow as regular vehicles, the number of collisions decreased by 128 collisions/hour in the early period, 393 collisions/hour in the mid period, and 337 collisions/hour in the late period. This indicates that the interaction between autonomous vehicles and conventional vehicles becomes more complex as the mixing ratio increases, and the effectiveness of the safe speed management measures proposed in this study increases accordingly. These results can be used as an important basis for transportation policy and design.

As the transportation paradigm shifts from vehicle-oriented to pedestrian-oriented, active research has been conducted on road designs that consider the safety of pedestrians, cyclists, and personal mobility users. This study aims to respond to this change by developing installation warrant factors and improving the minimum size design standards for triangular islands. This study involved reviewing domestic and international laws and guidelines, analyzing the current installation status of triangular islands, examining case studies of improvements, and assessing policy changes. Based on the findings, important insights were derived, and improvement plans to enhance the safety of pedestrians, vulnerable users, and other road users were proposed. This study identified several issues and confirmed that policies in both domestic and international contexts are shifting towards minimizing or removing the triangular islands. Based on these findings, this study developed 24 factors for installation warrants to determine the installation of triangular islands, such as the design speed and peak-hour volume for pedestrians. In addition, the proposed improvements suggest increasing the minimum size design standards from 9m2 to 22m2 to ensure the safety of users. The factors of installation warrants and improved minimum size design standards proposed in this study are expected to help shift the operation of triangular islands from a vehicle-oriented to a pedestrian-oriented approach.

This study evaluated the safety impact of automated traffic enforcement cameras targeting tailgating behavior at signalized intersections by comparing traffic conditions shortly after installation and one year later. The Kukkiwon intersection in Gangnam-gu, Seoul, South Korea was selected as the study site. Individual vehicle speeds, accelerations, and subsequent distances were extracted from video data using YOLOv8 and ByteTrack, which are advanced deep learning-based object detection and tracking algorithms. Surrogate safety measures (SSM), such as time to collision (TTC), modified time to collision (MTTC), and proportion of stopping distance (PSD), were calculated to assess changes in traffic safety. Every SSM indicated an improvement one year after the installation of enforcement cameras, suggesting a reduction in collision risks. In particular, the PSD indicator showed a notable improvement, reflecting a better maintenance of safe following distances. These results highlight the effectiveness of automated enforcement in improving intersection safety and suggest its scalability to other intersections with similar tail-gating issues. Future research should explore the long-term and multisite effects using diverse intersection types and behavioral indicators.

This study quantitatively assess the risk of ice-related accidents on road facilities such as bridges and tunnels, and examines the influence of road facility characteristics on ice-related accidents. Ice-related accident data from expressways and national highways in South Korea were collected over a 10-year period (2013–2022). Geographic information systems (GIS) and node-link systems were employed to classify accidents based on road facility types. The number of ice-related accidents per unit length and per individual segment was examined according to the road classification. Furthermore, the fatality rate and fatality-weighted indicator (FWI) were calculated to evaluate the severity of icerelated accidents.The number of ice-related accidents per unit length of road facilities is higher on national highways than on expressways. For both expressways and national highways, the incidence rate of ice-related accidents on bridges was higher than those on ordinary sections and tunnels. A greater number of ice-related accidents occurred on long-span bridges and tunnels for both road classifications. The fatality rate of ice-related accidents on expressways was approximately 1.5 times higher than that on national highways. The fatality rate of ice-related accidents occurring on road facilities within expressways was approximately three times higher than the overall fatality rate of ice-related accidents on expressways. On national highways, the fatality rate of ice-related accidents on bridges was higher than the overall fatality rate of ice-related accidents, whereas the fatality rate of ice-related accidents in tunnels was lower than that on national highways. The FWI of ice-related accidents on bridges and tunnels was more than twice that on ordinary sections on both expressways and national highways. Among expressway facilities, tunnels exhibited the highest FWI, whereas on national highways, the FWI values for bridges and tunnels were similar. The findings of this study suggest that the influence of road facilities on ice-related accidents should be considered in winter road maintenance strategies. This could contribute to reducing not only the frequency of ice-related accidents, but also the number of fatalities and injuries resulting from such incidents.

보행자 대기공간의 효과척도와 서비스수준 기준은 도로용량편람(2013)에서 제시되고 있다. 보행자 대기공간은 밀집하여 대기하는 공간으로, 횡단보도 대기공간, 지하철 역사, 대합실, 매표소, 엘리베이터 내 등이 이에 해당한다(도로용량편람, 2013). 효과척도는 점유공간으로 측정되며, 이는 보행자가 차지하는 평균 면적을 의미한다. 그러나 도로용량편람(2013)의 기준은 이전 도로용량편람(2001)과 동일한 수치를 적용하고 있어 현 상황을 반영하지 못하고 있다. 이에 따라 대부분의 분석 지점에서 서비스수준이 A로 산출되는 문제가 발생한다(김응철, 2015). 본 연구의 목적은 보행자 대기공간의 서비스수준을 최신화하는 것이다. 연구 절차는 다음과 같다. 첫째, 인체치수를 활 용하여 보행자 대기공간의 점유공간 면적을 재산정하고자 한다. 둘째, 문헌조사를 통해 서비스수준 등급별 기준을 재산 정하고자 한다. 셋째, 최신화된 서비스수준과 도로용량편람(2013)의 기준을 비교하고자 한다. 마지막으로, 현장조사를 통 해 최신화된 서비스수준의 적용 사례를 제시하고자 한다. 연구 결과, 보행자 대기공간의 점유공간 면적을 재산정하고, 이를 기반으로 서비스수준 등급별 기준을 재산정하였다. 도 로용량편람(2013)의 기준과 최신화된 서비스수준 간 차이를 확인하였다. 비교 결과, 점유공간이 2배 증가한 서비스수준임 을 제시하였다. 최신화된 보행자 대기공간 서비스수준을 이용한 실제 보행환경에 관한 적용 사례를 제시하였다.

중앙버스전용차로는 일반 도로 대비 높은 교통량과 반복적인 축하중이 작용하는 구간으로, 정차 및 출발 과정에서 발생 하는 국부적인 응력 집중으로 인해 포장 파손이 빈번하게 발생한다. 그러나 기존 도로 설계에서는 정적인 교통량을 기준 으로 축하중을 산정하여, 실제 교통 환경에서의 버스 유형별 차이, 재차 인원, 시간대별 하중 변화 등 동적인 요소를 충 분히 반영하지 못하는 한계가 존재한다. 이에 본 연구에서는 대중교통 빅데이터를 활용하여 중앙버스전용차로의 버스 유 형 및 시간대별 재차 인원을 반영한 새로운 축하중 산정 모델을 개발하였다. 이를 위해 서울시 열린 데이터 광장의 교통 정보를 활용하여 버스 유형 및 시간대별 재차 인원 데이터를 수집하고, 카카오맵 및 네이버 로드뷰 데이터를 이용해 결 측치를 보완하여 데이터셋을 구축하였다. 구축된 데이터셋을 활용하여 기존 ESAL(Equivalent Single Axle Load) 방식과 비교 분석한 결과, 새로운 축하중 모델에서는 기존 방식 대비 평균 111.8% 높은 축하중이 산정되었으며, 일부 구간에서 는 최대 128.9%까지 차이가 발생하는 것으로 나타났다. 이는 기존 포장 설계가 중앙버스전용차로의 실질적인 교통 하중 을 충분히 반영하지 못하고 있음을 시사하며, 추가적으로 버스 중하중의 가·감속의 영향을 고려한다면, 시간대별·노선별 실시간 축하중 변화를 보다 정밀하게 분석할 수 있으며, 이를 통해 과소 산정된 설계 하중을 보완하고 포장 공용성을 향 상시킬 수 있는 최적의 설계 및 유지보수 전략 수립이 가능할 것으로 기대된다.

늘어나는 교통 수요에 대응하기 위해 지하도로 건설이 추진 중이다. 지하도로 건설 시, 진출입부에서의 차량 간 합류 및 분류로 인해 교통정체 및 안전성 저하에 대한 우려가 제기된다. 교통정체가 빈번히 발생하는 경부고속도로 금토JCT-양재IC 구간에 서울-용인 지 하도로, 양재-한남 지하도로, 양재-고양 지하도로 건설이 예정되었다. 특정 구간에 다수의 지하도로 건설 시, 접속부 배치 및 위치에 따라 이동성 및 안전성이 변화할 것으로 고려된다. 본 연구에서는 서울-용인 지하도로와 양재-한남 지하도로, 양재-고양 지하도로에 대한 접속부 배치 및 위치에 따른 이동성 및 안전성 분석을 통해 교통혼잡 완화 및 교통안전이 증가하는 지하도로 연계 방안 도출하 였다. 본 연구에서는 지하도로 연계 방안별 이동성 및 안전성 분석을 위해 4가지 시나리오 (1안 : 지하도로 미시행, 2안 : 지하도로 미 연계, 3안 : 양재-고양 연계, 4안 : 양재-한남 연계)를 선정하였다. 교통 시뮬레이션을 활용해 지상도로 및 지하도로 네트워크를 구축 하고 지하도로 내 차량 주행행태를 구현하였다. 이동성은 평균 통행속도와 통과교통량비로 분석하였으며, 안전성은 상충률을 통해 분 석하였다. 이동성 분석결과, 지상도로 합류부에서는 시나리오 3안 (양재-고양 연계)이 지하도로에서 합류되는 교통량이 가장 적어 모 든 이동성 평가지표에서 가장 큰 이동성 개선 효과가 나타났다. 그러나, 지하도로 합류부에서는 시나리오 3안에 비해 시나리오 4안 (양재-한남 연계)이 이동성 개선 효과가 큰 것으로 나타났다. 이는 유사 교통량 대비 차로수 증가 및 지상도로 합류부 정체의 영향인 것으로 분석된다. 안전성 분석결과, 지상도로 합류부에서는 시나리오 3안이 안전성이 높았으나 지하도로 합류부에서는 시나리오 4안이 안전성이 더 높은 것으로 나타났다. 본 연구의 결과는 시나리오별 교통혼잡 완화 및 교통안전 증진 효과를 정량화해 지하도로 연계 방안 결정을 위한 예비타당성 조사에 반영하는 자료로 활용할 수 있을 것으로 기대된다.

지하도로는 폐쇄적인 공간 구조와 내·외부 조도 차이로 인해 지상도로와 다른 교통 환경을 형성하며 이러한 특성은 교 통사고에 영향을 미칠 수 있다. 특히 고속도로 터널에서 사고 발생 시 대형 인명 피해로 이어질 가능성이 크다는 점을 고려할 때 지하도로에서도 유사한 우려가 제기된다. 따라서 지하도로의 교통류 특성을 면밀히 분석하여 안전성을 평가하 고 사고 예방을 위한 효과적인 대책을 마련하는 것이 중요하다. 본 연구에서는 서부간선 지하도로 성산 방면의 14개 VDS 검지기 데이터를 기반으로 지점별 속도 변동성과 교통사고 분석을 통해 안전성을 평가하였고 분석 결과의 시사점 을 바탕으로 지하도로 속도 관리 전략을 설계하였다. 먼저, VDS 검지기 지점별 속도 표준편차와 time-varying-volatility 산출 및 속도의 변동성과 교통사고 데이터 매칭을 통해 사고 개연성과 심각도를 분석하였다. 이후, 사후검정을 통해 속 도 및 속도 변동성 기준으로 동질적 부분집합을 도출하고 회귀분석을 통해 속도 변동성과 교통량·밀도 간의 관계를 규명 하여 속도 변동성을 최소화할 수 있는 최적의 교통량과 밀도를 산출하였다. 분석 결과, 속도 변동성이 큰 구간에서 사고 개연성과 심각도가 높게 나타났으며 지하도로에 구간단속을 적용할 경우 하류부에서 변동성이 증가하는 현상을 확인하 였다. 이를 바탕으로 위험 구간을 식별하고 해당 구간에 가변형 속도 제한 시스템을 적용한 로컬 속도 관리 전략을 제시 하였다. 본 연구의 결과는 지하도로의 사고 예방 및 안전성 향상을 위한 실질적인 속도 관리 전략 설계에 기여할 수 있 을 것으로 기대된다.

국내에서 겨울철 발생하는 결빙사고는 전체적인 교통사고 대비 치사율이 1.7배 높은 것으로 나타났다. 주행속도가 높은 고속국도의 경우 결빙사고 치사율은 18.7로, 결빙 외 고속국도 교통사고 치사율인 4.2와 비교하여 약 4.5배 높았다(KoROAD, 2024). 특히 교량과 터널과 같은 도로시설물은 구조적 특성과 환경적 요인으로 인해 결빙 형성에 매우 취약하다. 교량은 지면으로부터의 열전달이 차단되 기 때문에 겨울철 노면온도가 낮아 결빙이 형성될 가능성이 높으며, 터널은 겨울철 낮은 온도와 터널 입출구부의 응달지역 형성 및 터널 내부와 외부 공기로 인한 급격한 온도변화로 인해 결빙이 발생할 가능성이 높다. 또한, 도로시설물은 교통사고 발생 시 치사율이 높게 나타나는 경향이 있다. 실제로 교량과 터널에서 발생한 교통사고의 치사율은 전체 1.94, 터널 5.05, 교량 4.10으로 도로시설물에서 발생한 교통사고의 치사율이 높았다(KoROAD and ACCRC, 2017). 따라서 도로시설물에서 발생하는 결빙사고는 쉽게 결빙이 형성되 는 환경조건과 사고 발생 시 치사율이 높은 특성으로 인해 일반 도로보다 높은 위험성을 내포하고 있다. 그러나 현재로써 도로시설물 에서 발생하는 결빙사고의 원인과 위험성을 중점적으로 분석한 연구는 그 수가 부족하며, 기존 연구들은 결빙 구간의 기후적 특성이 나 개별 결빙사고 사례 분석에 국한되어 있어 도로시설물은 결빙사고 분석 시 여러 가지 환경요인 중 하나로서만 고려되고 있는 실정 이다. 본 연구에서는 도로시설물에서의 결빙사고 위험도를 평가하는 방법을 제시하고, 이를 Min-Max(최소-최대) 정규화 과정을 통해 구체 화함으로써 보다 체계적인 분석이 가능하도록 한다. 이를 통해 도로시설물의 겨울철 운영에 있어 효과적인 결빙사고 방지 대책을 수 립하는 데 기여하고자 한다.

보행교통은 모빌리티 수단으로서의 보행을 말하며 안전향상과 활성화 측면에서 접근할 수 있다. 이때 보행교통 위해요 소란 보행자의 안전하고 편리한 통행 환경을 저해하는 요소를 말하며, 이를 사전에 발굴하여 관리함으로써 보행자 사고 예방과 쾌적한 보행환경 구축이 가능하다. 본 연구에서는 2020~2022년 교통사고 데이터와 다양한 보행영향요인 데이터 를 활용하여 교통사고 및 보행자 사고 예측 모델을 개발하고 모델 결과를 해석하여 보행교통 위해요소를 도출하고자 하 였다. 보행영향요인은 기존 문헌에서 고찰된 요인들을 참고하여 수집 및 데이터화 하였으며, 교통사고 예측 모델을 개발 하기 위해 예측력이 우수하고 변수 간의 비선형성 혹은 상호관계를 잘 포착할 수 있는 것으로 알려진 XGBoost, Random Forest, Support Vector Machine과 같은 머신러닝 모델을 활용하였다. 또한 설명가능한 인공지능 기법인 SHAP 알고리즘을 통해 모델을 해석함으로써 변수 중요도와 상호작용을 분석하고 보행교통 위해요소를 도출하였다. 본 연구를 통해 도출된 보행교통 위해요소를 보행친화적인 교통 환경을 위한 중요한 기초 자료로 활용하여 사전에 관리 및 개선할 수 있을 것으로 기대한다.

This study aims to to provide a systematic and sustainable strategic direction for road transportation ODA projects in Mozambique to help solve economic bottlenecks and contribute to national and regional economic growth at a time when the country is recovering from the economic shock and cessation of international aid caused by the past "Tuna Bond Scandal" and showing strong commitment to improving the road transportation sector led by the government. Through this, we aim to enhance the effectiveness of Korea's ODA projects and contribute to building a mutually beneficial cooperation model between Mozambique and Korea. Key indicators were established based on literature reviews, and an AHP survey was conducted targeting local road transport officials. The results were utilized to calculate the weights for each indicator and derive the project priorities. The study identified "sustainability" as the most critical factor among the social necessity indicators, highlighting the importance of long-term stability in road transport infrastructure. In the economic necessity category, "cost-effectiveness" emerged as a key priority, emphasizing resource optimization for maximum impact. Within policy necessity, alignment with government development goals was deemed essential for project success. Prioritization of road transport ODA projects based on sustainability, cost-effectiveness, and alignment with government policies is concluded to significantly enhance their impact. By addressing the immediate and long-term needs of Mozambique's transport infrastructure, the proposed strategy ensures resource efficiency and socioeconomic benefits. This approach not only improves the effectiveness of ODA initiatives but also fosters stronger partnerships between donor and recipient countries. Ultimately, the findings contribute to the development of systematic and sustainable ODA strategies for Mozambique.

In this study, we propose an adaptive traffic control method that utilizes predictions of near-future traffic arrivals at a signalized intersection based on real-time data collected at an upstream intersection to design acyclic traffic signal timing accordingly. The proposed adaptive control method utilizes a deep learning model developed in this study to predict future traffic arrivals at downstream intersections 24 s ahead based on upstream intersection data at 4 s decision intervals. Using the predicted arrival traffic volume, signal timings were designed to minimize delays. A rolling-horizon approach was employed to correct the prediction errors during this process. The performance of the proposed traffic signal control method was validated by comparing it with the traditional time-of-day (TOD) traffic signal operation method over a 24 h period. The results of comparative validation tests conducted through simulations in a virtual environment indicate that the proposed adaptive traffic control system operates efficiently to minimize average control delays. During the morning peak period, a reduction time of 43.19 s per vehicle (57.02%) was observed, whereas the afternoon peak period exhibited a reduction of 37.91 s per vehicle (48.35%). Additionally, data analysis revealed that the optimal phase length suggested by the pre-timed method, which assumes uniform vehicle arrivals, is statistically identical at a 95% confidence level to the average phase length of the adaptive traffic control system, which assumes random vehicle arrivals. This study confirms the necessity of adopting proactive real-time signal control systems that utilize a new traffic information collection method to respond to dynamic traffic conditions and move away from conventional TOD signal operation, which primarily focuses on peak commuting hours. Additionally, it confirms the need for a fundamental shift in the underlying philosophy traditionally used in traffic signal design

Until all vehicles are equipped with autonomous driving technology, there will inevitably be mixed traffic conditions that consist of autonomous vehicles (AVs) and manual vehicles (MVs). Interactions between AVs and MVs have a negative impact on traffic flow. Cloverleaf interchanges (ICs) have a high potential to cause traffic accidents owing to merging and diverging. Analyzing the driving safety of cloverleaf ICs in mixed traffic flows is an essential element of proactive traffic management to prevent accidents. This study proposes a comprehensive simulation approach that integrates driving simulation (DS) and traffic simulation (TS) to effectively analyze vehicle interactions between AVs and MVs. The purpose of this study is to identify hazardous road spots for a freeway cloverleaf IC by integrating DS and TS in mixed traffic flow. The driving behavior data of MVs collected through a DS were used to implement vehicle maneuvering based on an intelligent driver model in the TS. The driving behavior of the AVs was implemented using the VISSIM parameters of the AVs presented in the CoEXist project. Additionally, the market penetration rate of AVs, ranging from 10% to 90% in 10% increments, was considered in the analysis. Deceleration rate to avoid crashes was adopted as the evaluation indicator, and pinpointing hazardous spot technique was used to derive hazardous road spots for the cloverleaf IC. The most hazardous road spot was identified in the deceleration lane where greater speed changes were observed. Hazardous road spots moved downstream within the deceleration lane as traffic volumes increased based on level of service. The number of AVs decelerating stably increased as traffic increased, thereby improving the safety of the deceleration lane. These results can be used to determine the critical point of warning information provision for preventing accidents when introducing AVs.

In this study, we aim to classify personal mobility (PM)-related traffic crash data into four categories: PM-to-vehicle, PM-to-pedestrian, PM-single, and vehicle-to-PM crashes, and analyze the factors influencing the severity of each crash type. To overcome the limitations of existing studies in explaining the impact of independent variables on ordinal dependent variables, a random forest model was combined with the Shapley additive explanation technique. This approach visualizes the influence of independent variables on a dependent variable, providing clearer insights and enhancing interpretability. The analysis of PM traffic accidents, categorized into at-fault, single-vehicle, and victim accidents, revealed distinct key factors for each type. The main contributors to the severity of crashes caused by PM are traffic violations by teenagers and collisions with elderly pedestrians. Single-vehicle accidents were predominantly caused by overturn incidents, with inadequate driving skills among PM users aged 40 years and older, and significantly increasing severity. Victim accidents primarily occur at intersections, where the behavior of the at-fault driver and age of the PM user are critical factors influencing the severity. We identified various factors influencing the severity of PM crashes by type, highlighting the need for tailored policy measures. Proposed policies include physically separating bicycle–pedestrian shared spaces and strictly regulating illegal PM sidewalk riding, introducing PM licenses for teenagers to ensure compliance with traffic rules, and implementing regular safety education programs for all age groups. Although this study applied a new analytical technique, it relied on limited crash data, thus limiting the results to estimates.

This study analyzed actual traffic accident data to select humans’ unavoidable accidents and to examine whether avoidance is possible after AEBS(Advanced Emergency Braking System) is applied to these accidents. In cases where avoidance is not possible with AEBS, those accidents were determined to be examples where V2X(Vehicle-to-Everything) technology is necessary. Subsequently, by applying V2V(Vehicle-to-Vehicle) and V2I(Vehicle-to-Infrastructure) communication technologies, this research analyzed the possibility of accident avoidance. The results confirmed that the application of V2X technology enables accident avoidance. Additionally, by applying various variables, it identified limitation scenarios that cannot be resolved by V2X technology, and discussed strategies for accident avoidance in such situations.