Motorcycles are becoming a major means of transportation in the delivery industry because of their mobility and economic feasibility, and their use is increasing with the spread of non-face-to-face culture. However, owing to the absence of a systematic maintenance and inspection system, illegal modifications, and a lack of safety education, the possibility of accidents is increasing, and social problems are intensifying. To address this issue, we aim to find ways to improve motorcycle safety. Problems were identified by registering motorcycles, driver crashes, and surveys of the current status of laws and systems. Subsequently, a questionnaire was administered to assess the actual conditions and perceptions regarding motorcycles. Finally, to analyze the driving characteristics of delivery motorcycles, traffic safety education was conducted for new delivery riders, and the driving characteristics were analyzed by collecting driving record data. In this study, a plan to enhance the license system, education, insurance, and educational programs is proposed to strengthen motorcycle safety. The licensing system needs to be elevated by age and classified by displacement, and delivery riders can improve their driving skills through mandatory traffic safety education. The insurance sector should introduce a system that discounts insurance premiums upon completion of training. Additionally, it is essential to prepare a systematic education program, including obstacle avoidance and simulation-based learning, by reflecting on the analysis results of road environments and driving data. In this study, insensitivity to safety, insufficient management systems, and lack of education and publicity were identified as causes of motorcycle driver crashes. It was confirmed that most types of dangerous driving were improved through traffic safety education. However, some limitations were observed, such as an increase in the right-hand rotation over time during sudden turns. Future research is needed to enhance laws, systems, and driver safety by analyzing driving characteristics in a broader context based on actual driving records and images.

본 연구는 자율주행상황에서 주관적인 운전 준비도를 객관적으로 측정할 수 있는 심리⋅생리적 지표를 확인하는 것을 목적으로 한다. 51명의 연구대상자가 참여하였고, 설문을 통해 운전 경험, 태도, 운전부하, 상황인식 등을 평가 하였다. 자율주행 중 차량 제어권을 인계받아야 하는 시나리오 동안 심전도를 측정하여 심박변이도 지표를 추출하였 고, 주행 종료 후 연구대상자는 자신의 상태를 평가하였다. 분석 결과, 운전 준비도는 정신적 부하와 부적 상관, 상황 인식과 상황 이해도와는 정적 상관을 보였다. 또한, 심박변이도 지표인 제곱 평균 근간 심박 간격 차이(Root Mean Square of Successive Differences, RMSSD)와 50ms 이상의 연속적인 RR 간격의 차이 비율(proportion derived NN50 by the total number of NN interval, pNN50)과의 유의한 정적 상관관계가 확인되었다. 운전 준비도 수준에 따라 상⋅중⋅하로 나누어 분석한 결과, 높은 운전 준비도 집단은 정신적 부하가 낮고 상황인식 및 상황에 대한 이해 도가 유의하게 높았으며, 자율주행 구간에서 pNN50이 높은 경향이 있었다. 마지막으로 상황인식과 RMSSD가 운전 준비도의 주요 예측 지표로 확인되었다. 이는 운전 준비도가 낮은 운전자는 자율신경 각성이 높고, 높은 운전자는 부교감신경계의 활성화로 인해 심리적, 생리적으로 안정된 상태임을 의미한다. 본 연구는 운전자의 주관적인 운전 준비도를 예측하기 위한 운전자의 심리 및 생리 지표를 확인하였고, 이는 운전자의 운전 준비 상태를 모니터링하는 기술에 적용되어 사고 예방에 기여할 수 있을 것이다.

도로 주행의 안전성 측면에서 타이어-노면간 미끄럼 마찰력은 주행 차량의 제동거리와 직접적인 요인으로 작용한다. 포장재료와 공법은 노출되는 포장 표면에 적절한 노면의 조직(Texture)을 형성하여 노면의 미끄럼 마찰력을 증가시킨다. 도로 표면에 노출되는 사용골재의 크기와 종류를 달리하거나 인위적인 홈을 주어 Macrotexture와 Microtexture를 형성 한다. 형성된 노면 조직은 시간이 경과 됨에 따라 환경하중과 교통하중이 반복 재하되면서 표면마모가 급격히 진행된다. 교통량의 흐름에 따라 마모로 인해 Microtexture 뿐만 아니라 Macrotexture의 노면조직은 매끄러운 표면으로 변해간다. 교통량의 흐름은 다양하다. 교통량 통계자료에 따르면 고속도로 이용차량의 약 70%는 승용차와 같은 2축 1단위로 구성 된 1종 차량이 차지하고 있다. 이는 국내 교통 특성은 포장 마모에 취약한 환경임을 말해주고 있다. 주행 차량들의 좌/ 우 바퀴의 간격과 주행위치의 다른 궤적에 따라 차량바퀴의 횡방향 변동을 원더링(Wandering)이라하는데, 도로포장 분 야에서 교통특성이 포장에 미치는 영향으로 원더링에 대한 연구 많이 진행 되어왔다. 본 연구에서는 실제 고속도로와 시 험도로에서 횡방향 위치별 미끄럼 마찰을 반복 조사하여 차량의 원더링에 따라 미끄럼 마찰저항이 다르게 분포함을 정 량적으로 입증하였다.

본 연구는 보행로에서 주행하는 자율주행로봇의 경로 최적화를 위한 D*알고리즘 수정에 중점을 두고 있다. 기존의 D*알고리즘은 자율주행 로봇이 장애물을 인식하고 회피하는 방식으로 설계되었지만, 실제 보행환경에서는 보행로를 통행하는 사람들이 로봇을 인지 하고 스스로 회피하는 경향이 관찰되었다. 라이다 센서를 통해 수집된 사람들의 궤적 데이터를 분석하여, 사람들이 자율주행 로봇을 회피하기 시작하는 평균 거리와 회피 각도를 파악하였다. 이를 바탕으로, 사람들이 로봇을 회피할 의사가 있을 때 로봇이 기존 최적경 로를 유지하도록 하고, 그렇지 않은 경우에만 회피 경로를 채택하는 수정된 D*알고리즘을 제안하였다. 실험 결과, 수정된 D*알고리즘 을 적용한 자율주행 로봇은 운행 효율과 주행 시간 측면에서 기존 방식 대비 우수한 성능을 보였다. 이러한 연구는 제한된 배터리 용 량 하에서도 효율적인 주행이 가능하도록 하여 자율주행 로봇의 보행로 사용을 최적화하는 데 기여할 것으로 기대된다.

PURPOSES : The purpose of this study is to identify the causes and expected problems of traffic flow in connection with ground roads that are expected to become stagnant owing to the increase in underground road infrastructure, and to derive methods to solve the problem in the future. METHODS : The basic design of underground roads is similar to that of tunnels. However, there is a point where the slope is large as the entering and exiting sections move underground. The ability of a heavy vehicle to assume a mound may vary depending on the slope. Therefore, in this study, a connection path section with a long slope was constructed using VISSIM, a simulation program, and it was verified whether analysis related to the slope and heavy vehicles in an underground road can be performed in the simulation. Subsequently, an analysis was conducted by setting a scenario and an effect index. In particular, this study analyzes internal delay patterns in the event of an unexpected situation on an underground connection road by performing shock wave analysis to analyze speed reduction according to heavy vehicles and slopes. RESULTS : A correlation between the slope of the underground road and decrease in the average speed according to the increasing rate of heavy vehicles was established. It was also possible to analyze the maximum length and duration of the delay connected to the rear in the event of a delay in the underground road and the shock wave speed transmitted to the rear. The analysis showed that the rate of increase in problems owing to delays ranged from 5% to 20% for the ratio of heavy vehicles. In particular, all effect scales increased significantly at a 9% slope. CONCLUSIONS : This study analyzes the causes of land congestion (slope and heavy vehicle mixing rate), which can be a major problem in underground roads in the future. In the future, by establishing lane-specific speed control strategies and lane control strategies based on this study, it will be necessary to derive solutions such as introducing traffic safety on the underground road by minimizing the shock wave delivered to the rear by providing information on traffic communication conditions inside the underground road to individual vehicles.

PURPOSES : This study aims to perform a quantitative analysis of Forward Collision Warning and crash frequency using heavy vehicle driving data collected in expressway driving environments, and to classify the driving environments where Forward Collision Warnings of heavy vehicles occur for accident-prone areas and analyze their occurrence characteristics. METHODS : A bivariate Gaussian mixture model based on inter-vehicle distance gap and speed-acceleration parameters is used to classify the environment in which Forward Collision Warning occurs for heavy vehicles driving on expressways. For this analysis, Probe Vehicle Data of 80 large trucks collected by C-ITS devices of Korea Expressway Corporation from May to June 2022. Combined with accident information from the past five years, a detailed analysis of the classified driving environments is conducted. RESULTS : The results of the clustering analysis categorizes Forward Collision Warning environments into three groups: Group I (highdensity, high-speed), Group II (high-density, low-speed), and Group III (low-density, high-speed). It reveals a positive correlation between Forward Collision Warning frequency and accident rates at these points, with Group I prevailing. Road characteristics at sites with different accident incidences showed that on-ramps and toll gates had high occurrences of both accidents and warnings. Furthermore, acceleration deviation at high-accident sites was significant across all groups, with variable speed deviations noted for each warning group. CONCLUSIONS : The Forward Collision Warning of heavy vehicles on expressways is classified into three types depending on the driving environment, and the results of these environmental classifications can be used as a basis for building a road environment that reduces the risk of crashes for heavy vehicles.

PURPOSES : The purpose of this study was to quantitatively evaluate the variability of LiDAR performance indicators, such as intensity and Number of Point Cloud(NPC), according to various environmental factors and material characteristics. METHODS : To consider the material characteristics of road safety facilities, various materials (Reference Material(RM), reflective sheet, matte sheet, granite, plastic, and rubber) were used in a darkroom, and the performance indicators of LiDAR were repeatedly measured in terms of changes in the measurement distance, rainfall, and angle of observation. RESULTS : In the case of standard reflective materials, the intensity measurement value decreased as the measurement distance and rainfall increased. The NPC showed a tendency to decrease as the measurement distance increased, regardless of rainfall intensity. For materials with high-intensity values, it was found that rainfall intensity and color had negligible effect on the change in intensity compared with the measurement distance. However, for materials with low-intensity values, it was found that the measurement distance, rainfall intensity, and color all had a significant effect on the change in intensity. CONCLUSIONS : For materials with high-intensity values, it was found that rainfall and color had negligible effect on change in intensity compared with the measurement distance. However, for materials with low-intensity values, the measurement distance, rainfall, and color all had a significant effect on the change in intensity value.

The purpose of this study is to investigate the distribution patterns of displacement and acceleration fields in a nonlinear soil ground based on the interaction of high-speed train, wheel, rail, and ground. For this purpose, a high-speed train in motion was modeled as the actual wheel, and the vertical contact of wheel and rail and the lateral contact, caused by meandering motion, were simulated; this simulation was based on the moving mass analysis. The soil ground part was given the nonlinear behavior of the upper ground part by using the modified the Drucker– Prager model, and the changes in displacement and acceleration were compared with the behavior of the elastic and inelastic grounds. Using this analysis, the displacement and acceleration ranges close to the actual ground behavior were addressed. Additionally, the von-Mises stress and equivalent plastic strain at the ground were examined. Further, the equivalent plastic and total volumetric strains at each failure surface were examined. The variation in stresses, such as vertical stress, transverse pressure, and longitudinal restraint pressure of wheel-rail contact, with the time history was investigated using moving mass. In the case of nonlinear ground model, the displacement difference obtained based on the train travel is not large when compared to that of the elastic ground model, while the acceleration is caused to generate a large decrease.

PURPOSES : This study was conducted to develop expressway safety treatments based on the analysis results of older driver behaviors through literature review, surveys, and driving simulator experiments. METHODS: In this study, three analyses were conducted: surveys of 700 older drivers to find the risk segments they recognized, driving simulator experiments with older and younger drivers to investigate driver behaviors, and expert surveys to find the priority of expressway safety treatments for older drivers. RESULTS : Through survey results it was found that merging areas and tunnels were identified as the most dangerous areas, and more dangerous older driver behaviors were observed on those expressway segments in the driving simulator experiments. In addition, the priorities of safety treatments for each segment of expressways were decided based on expert surveys. CONCLUSIONS: It was concluded that choice and concentration strategies of expressway safety treatments for older drivers should be applied as perceptions regarding dangerous spots and older driver behaviors, including geometric designs, safety facilities, regulation, and institutes to improve expressway safety.

교통 분야의 빅데이터 수집 및 활용은 기존에 명확하게 제시하지 못했던 다양한 분야의 연구를 가능하게 하고 있다. 특히 내비게이션 등의 개별차량 주행데이터의 경우 운전자가 주행을 시작한 시점부터 종료 한 시점까지의 주행시간과 거리, 경로 등의 데이터 수집이 가능하기 때문에 보다 다양한 분석과 정확한 결과 제시가 가능한 양질의 데이터라 할 수 있을 것이다. 기존의 경우 권역별 통행특성을 파악하기 위해 고속도로 VDS 교통량과 영업소별 통행량 자료 등을 활용하였으나, 해당 자료의 경우 고속도로를 주행한 차량에 한정되고 차량의 기점과 종점이 고속도로 영업소로 제한되기 때문에 세부 권역별 차량의 통행특성을 파악하는 것에 한계가 있으며, 운전자가 실제 주행한 총 통행시간과 휴식여부 등을 파악하는 것에도 한계가 있다. 본 연구에서는 위와 같은 문제점을 극복하기 위한 방안으로 SK텔레콤 Tmap(내비게이션)을 사용하여 하계휴가기간(2017년 7월 31일∼2017년 8월 6일) 중 수도권에서 강원권으로 이동한 개별차량의 주행데이터를 수집하여 기종점간 평균 통행시간, 고속도로 경로선택, 평균 휴식시간 등을 분석하였다. 하계휴가 기간 중 Tmap을 사용하여 수도권과 강원권(속초, 양양, 강릉, 동해, 삼척)을 이동한 통행은 총 109,621통행이며, 이중 수도권에서 강원권으로 이동한 통행이 총 50,648통행이고 해당 차량들의 평균 통행시간은 205분, 강원권에서 수도권으로 이동한 통행은 총 58,973이고 해당 차량들의 총 통행시간은 217분으로 검토되었다. 이밖에 위에서 수집된 통행량을 수도권 5개 권역(경기 남부/북부, 서울 강남/강북, 인천)과 강원권 3개 권역(속초·양양, 강릉, 동해·삼척)으로 구분하고 각각의 권역별 통행량을 기준으로 주요 이동경로와 통행시간 등의 상세분석을 시행하였으며, 분석기간 중 서울양양고속도로를 이용하여 경기 북부에서 속초·양양으로 이동한 통행량이 6,290통행으로 가장 높은 통행량을 나타냈으며, 해당 차량들의 평균 통행시간은 약 173분인 것으로 나타났다

PURPOSES : Because elderly drivers are more prone to becoming confused when approaching an urban intersection and thus may yield prolong judgment and decision times than non-elderly drivers, to increase the comfort and safety of the intersection environment for elderly drivers, this study applied autonomous driving tests at an urban intersection to examine their driving characteristics. METHODS: To obtain a more comprehensive understanding of driving features, this study collected drive data of non-elderly drivers and elderly drivers via an autonomous experiment using OBD2 and an eye-tracker, in addition to performing a literature review on the measured visibility range of elderly drivers at intersections. This literature review was conducted considering the general knowledge of elderly drivers having relatively reduced visibility. Additionally, as they are commonly more vulnerable, this study analyzes characteristics of elderly drivers as compared to those of non-elderly drivers. CONCLUSIONS: The results of this study can be summarized as follows: 1) the peripheral visible distance of elderly drivers is reduced as compared to that of non-elderly drivers; 2) elderly drivers approach and proceed through intersections at slower speeds than non-elderly drivers; and 3) elderly drivers yield increased driving distances when performing a right or left turn as compared to non-elderly drivers as a result of their reduced speed and acceleration and larger turning radii relative to non-elderly drivers.

PURPOSES: The objective of this study was to analyze variations in the vehicle driving behavior characteristics on signalized intersections according to the use of traffic enforcement camera (red light camera). METHODS: In order to analyze the driving behavior characteristics on signalized intersections when red light camera are installed, the target sites for investigation were selected depending on whether the red light camera is installed and accident rates increased after the installation. In particular, to analyze the characteristics of dilemma zones in signalized intersections, approach speed and deceleration speed of 3 type vehicles (passing vehicles during a yellow light, stopping at a yellow light, passing vehicles during a green light) were examined. Based on these data, the starting point, ending point, and distance of the dilemma zones were calculated. Also, the locations of increased traffic accidents and decreased accidents after the installation of the equipment were distinguished when analyzing the traffic accident characteristics. RESULTS : Analysis results revealed that there was a tendency for the dilemma zone distance to decrease after the installation of equipment(red light camera) in most sites. This tendency was found to be due to the decrease in the approaching speed of vehicles at intersections after the installation of equipment, resulting in the starting and ending points of dilemma zone to become closer to the stop line. Moreover, analysis showed that the number of traffic accidents decreased for most intersections after the installation of equipment and safety of the intersections increased somewhat. CONCLUSIONS : In general, installation of equipment(red light camera) caused the intersections approaching speed and dilemma zone distance to decrease. Decision-making is difficult for drivers in the dilemma zone, so the decrease in the dilemma zone distance implies an improvement in traffic safety. Furthermore, the number of accidents within intersections significantly decreased after the equipment was installed, leading to the conclusion that installation of the equipment affected the decrease in traffic accidents.