Autonomous vehicle (AV) technology is rapidly entering the commercialization phase driven by advancements in artificial intelligence, sensor fusion, and communication-based vehicle control systems. Real-world road testing and pilot deployments are increasingly being conducted, both domestically and internationally. However, ensuring the safe operation of AVs on public roads requires not only technological advancement of the vehicle itself but also a thorough pre-evaluation of the road environments in which AVs are expected to operate. However, most previous studies have focused primarily on improving internal algorithms or sensor performance, with relatively limited efforts to quantitatively assess how the structural and physical characteristics of road environments affect AV driving safety. To address this gap, this study quantitatively evaluated the compatibility of road environments for AV operation and defined the road conditions under which AVs can drive safely. Three evaluation scenarios were designed by combining static factors such as curve radius and longitudinal gradient with dynamic factors such as level of service (LOS). Using the MORAI SIM autonomous driving simulator, we modeled the driving behaviors of autonomous vehicles and buses in a virtual environment. For each scenario, the minimum time to collision (mTTC) from the moment the AV sensors detected a lead vehicle was calculated to assess risk levels across different road conditions.The analysis revealed that sharper curves and lower service levels resulted in significantly increased risk. Autonomous buses exhibited a higher risk on downhill segments, autonomous vehicles were more vulnerable to uphill slopes and gradient transitions. The findings of this study can be applied to establish road design standards, develop pre-assessment systems for AV road compatibility, and improve AV route planning and navigation systems, thereby providing valuable implications for policy and infrastructure development.

This paper presents a novel methodology for assessing the vulnerabilities of autonomous vehicles (AVs) across diverse operational design domains (ODDs) related to road transportation infrastructure, categorized by the level of service (LOS). Unlike previous studies that primarily focused on the technical performance of AVs, this study addressed the gap in understanding the impact of dynamic ODDs on driving safety under real-world traffic conditions. To overcome these limitations, we conducted a microscopic traffic simulation experiment on the Sangam autonomous mobility testbed in Seoul. This study systematically evaluated the driving vulnerability of AVs under various traffic conditions (LOSs A–E) across multiple ODD types, including signalized intersections, unsignalized intersections, roundabouts, and pedestrian crossings. A multivariate analysis of variance (MANOVA) was employed to quantify the discriminatory power of the evaluation indicators as the traffic volume was changed by ODD. Furthermore, an autonomous driving vulnerability score (ADVS) was proposed to conduct sensitivity analyses of the vulnerability of each ODD to autonomous driving. The findings indicate that different ODDs exhibit varying levels of sensitivity to autonomous driving vulnerabilities owing to changes in traffic volume. As the LOS deteriorates, driving vulnerability significantly increases for AV–bicycle interactions and AV right turns at both signalized and unsignalized intersections. These results are expected to be valuable for developing scenarios and evaluation systems to assess the driving capabilities of AVs.

목적 : 본 연구는 전북지역 거주 노인의 이동 현황과 자가운전 인식을 조사하여 노인의 이동권에 관한 기초자료를 제시하 고 시사점을 논의하고자 한다. 연구방법 : 2024년 7월 22일부터 동년 8월 16일까지 전라북도 소재 노인복지기관을 방문하여 65세 이상 노인을 대상으로 이동 현황과 자가운전 인식에 대한 설문조사를 실시하였다. 배포된 설문지 200부 중 195부를 회수하였고, 이 중 불분명한 설문지 33부는 제외하여 총 162부를 자료 분석에 활용하였다. 자료 분석은 기술통계와 다중응답 분석을 사용하였다. 결과 : 연구 참여자들은 버스(34.6%), 자가운전(32.1%), 이륜차(16%) 순으로 이동 수단을 활용하는 것으로 나타났으며, 주로 복지시설(31.1%)과 병원 진료(23.7%), 사회활동(17.5%)을 위해 교통수단을 이용하는 것으로 나타났다. 노인들이 인 식하는 운전의 주요 제약 요인은 시력 저하(38.3%), 반응 속도 저하(21.0%), 인지 저하(14.8%) 순의 결과를 보였다. 연 구 참여자 53.1%는 자가운전이 필요하다고 응답하였고, 반면에 면허 반납에 대한 인식은 69.1% 수준으로 높은 필요성을 보였다. 연구 참여자 40.7%는 운전중단 시기를 스스로 운전을 못한다고 생각할 때로 응답한 비율이 가장 높았다. 운전 재활에 대한 인식률은 91.4%로 매우 낮게 나타났고, 자가운전 지속을 위해 필요한 도움으로 운전 재활 전문가의 교육이 33.3%로 가장 높게 나타났다. 결론 : 본 연구는 전북지역 노인의 이동 현황과 자가운전에 대한 인식을 조사하여 주요 이동 수단, 이용 목적, 자가운전의 제약 요인 및 면허 반납에 대한 인식을 파악하고 정책 및 제도 수립을 위한 기초자료를 제공하였다. 향후 연구에서는 연 구 대상 지역과 집단의 범위를 확대하고, 운전중단 이후의 대체 교통수단과 운전 재활 지원 방안에 대한 후속 연구가 필 요하다.

목적 : 본 연구는 뇌손상 환자의 운전 적합성 여부에 따른 일반적 특성과 인지-지각 능력의 차이를 분석하는 것을 목적으 로 한다. 연구방법 : 본 연구는 회복기 재활의료기관에서 뇌손상 환자 46명을 대상으로 진행되었다. 연구 대상자는 CPAD(Cognitive Perceptual Assessment for Driving)를 이용한 운전 적합성 평가 결과에 따라 운전 가능군(19명), 경계군(19명), 운전 불가능군(8명)으로 분류되었다. 연구 대상자의 일반적 특성과 인지-지각 능력(거리 지각, 주의력, 실행 기능 등)을 분석하 였으며, 그룹 간 차이는 크루스칼-왈리스 검정과일원배치 분산분석을 이용하여 검증하였다. 결과 : 연령이 증가할수록 운전 적합성이 낮아지는 경향이 확인되었으며(p<.05), 성별, 편마비 측, 손상 원인에 따른 유의 한 차이는 없었다. 또한, 운전 가능군이 거리 지각, 지속적 주의력, 스트룹 검사 등에서 유의하게 높은 점수를 보였으며 (p<.05), 특히 스트룹 검사와 분할 주의력에서 운전 가능군과 운전 불가능군 간의 차이가 가장 두드러졌다(p<.001). 결론 : 본 연구는 운전 적합성이 인지-지각 능력과 밀접한 관련이 있음을 확인하였으며, 회복기 재활의료기관에서 운전 평가 및 중재의 필요성을 강조하였다. 향후 연구에서는 실제 도로 주행 평가와 비교하여 보다 체계적인 운전 재활 프로그 램을 개발할 필요가 있다.

Korea has many test beds where various mobility services are provided by automated vehicles. The test beds are operated in their operational design domain (ODD). However, disengagement frequently occurs, even in the ODDs of automated vehicles. In particular, human drivers have to take control of the automated vehicles at SAE Level 3 whenever the vehicles cannot drive by themselves because of an emergency or unknown factors. This study analyzed the driving safety of right turning at signalized intersections where automated vehicles face selfdriving issues because of potential conflicts with other vehicles, crossing pedestrians, and geometric factors. To conduct this analysis, we categorized right-turning intersections into two types with right-turning lanes and channelization islands and divided them into three sections, with a total of six sections. Subsequently, the six sections were compared with each other by disengagements of the automated vehicles as the key index to investigate their self-driving safety. Their significant differences indicate that ODD-related variables must be considered when designing and updating target test beds for automated vehicles.

자율주행 차량이 상용화됨에 따라 연구에 사용할 수 있는 자율주행 차량의 주행궤적 자료를 제공하고 연구하는 기관이 증가하고 있다. 캘리포니아 자동차관리국은 사고 당시 차량의 거동과 주변 환경을 기록한 자율주행 차량 사고 보고서를 제공한다. Waymo는 라이다, 카메라 등을 통해 수집한 자율주행 차량의 실주행 자료를 제공한다. 본 연구에서는 캘리포 니아 자동차관리국에서 제공하는 자율주행 차량 사고 보고서와 Google Street Map을 이용하여 사고 당시의 도로유형과 도로환경요소 및 사고 당시 상황을 파악하고, 베이지안 네트워크(BN)을 통해 자율주행 차량 사고 영향요인을 파악하였 다. 랜덤 포레스트를 통해 앞에서 파악한 자율주행 차량 사고 영향요인들의 변수 중요도를 추출하고 이를 기반으로 자율 주행 차량 주행 시나리오를 도출하였다. 도출한 자율주행 차량 주행 시나리오와 유사한 상황을 보이는 Waymo Open Dataset의 자율주행 차량 실제 주행궤적을 매칭하여 자율주행 차량 주행 행태 기반 사고 위험도 평가 지표를 도출하였 다. 본 연구의 결과는 앞으로 도로환경요소 및 자율주행 차량 주행궤적에 따른 자율주행 차량 주행 안전성 연구의 기반 이 될 것으로 기대된다.

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.

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.

The launcher of a hard-kill type APS (Active Protection System) requires rapid and precise driving to aim at incoming threats after detection. High angular acceleration is necessary for rapid driving, which demands high energy consumption. However, the capacity of the capacitor bank and power supply unit is limited due to weight and space constraints. If energy becomes insufficient during continuous operation, the voltage of the capacitor bank can drop below the minimum operating voltage of the drive motor, leading to problems such as torque deficiency. Therefore, it is necessary to determine an allowable angular acceleration that satisfies precision within the available energy and generate a driving profile accordingly. This paper proposes a method for deriving an allowable angular acceleration by analyzing the allowable energy and validates it through simulation. We examined the allowable energy by verifying the charged voltage of the capacitor bank, formulated equations for energy at the point of maximum consumption, and derived an equation for allowable angular acceleration through numerical analysis. By applying the proposed algorithm in simulations, we confirmed that the voltage of the capacitor bank did not drop below the minimum operating voltage of the driving motor during three consecutive operations. Therefore, it is expected that the stability of the APS launcher can be improved by applying the proposed algorithm, and continuous operation with limited performance is anticipated to be possible.

Along with the increase in the number of vehicles in circulation, the indoor air quality in automobiles is attracting attention as another possible health concern. However compared to data regarding indoor air quality in other spaces, there are insufficient data on indoor air quality in automobiles. In addition, there is no standard for the evaluation method. In this study, the change in the concentration of particulate matter in the vehicle while driving under real road conditions was analyzed in order to use it as basic data for a method to evaluate vehicle indoor air quality. Through the selection of measurement target materials and test vehicles and the preparation of test methodologies, evaluation was performed on vehicle, route, and HVAC modes. The concentration of particulate matter in the vehicle was the lowest in the RC (In-vehicle recirculation) condition, and it was confirmed that it decreased with time. The highest average concentration was confirmed in the OA (Outside air ventilation) condition, and the concentration change according to the changing HVAC mode was observed in the Auto condition. The concentration of pollutants inside the vehicle showed a significant correlation with factors such as season, external concentration, and HVAC conditions, along with a weak correlation to powertrain type. The results of this study can be used as basic data for developing methods for evaluating vehicle interior air quality in future work.

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.

This study aimed to develop a comprehensive validation methodology for an Infra-guidance system, which is an infrastructure-based service aimed at enhancing the safety of autonomous driving. The proposed method includes quantitative techniques for validating both the Infra-guidance algorithm module and the guidance message module using each optimal indicator. In addition, a promising method is suggested to validate the entire system by applying a multicriteria decision methodology. The relative weight for the algorithm module was higher than relative weight for the message module. Moreover, the relative weight of the latency for the message module was slightly higher than weight of the packet error rate. The proposed methodology is applicable for validating the performance of infrastructure-based services for enhancing connected autonomous driving based on the comprehensive quantification of various factors and indicators.

목적 : 본 연구는 20대 건강한 초보운전자를 대상으로 음주운전이 운전에 미치는 영향을 알아보고자 하였다. 또한 초보운 전자의 음주운전에 대한 인식을 높이기 위한 근거를 제공하는 것을 목적으로 하였다. 연구방법 : 단면적 연구 수행으로 22명이 연구에 참여하였으며 연구 참여자는 음주 운전을 시뮬레이션하기 위해 3가지 음 주 안경(Fatal Vision Gogles, FVG)을 번갈아 착용하고 운전 시뮬레이터(GDS-300, Gridspace, 서울, 한국)를 사용하 였다. (1) 위약 고글, (2) 저용량 알코올 고글, (3) 고용량 알코올 고글의 세 가지 실험 조건에서 UFOV 평가(처리 속도, 분리 집중력, 선택적 집중력), 인지 평가, 점수 차감 및 결격을 사용하여 운전 능력을 측정하였다. 결과 : 연구 참여자의 평균 연령과 운전 경력은 각각 21.6±2.3세와 23.6±16.2개월이었다. 수집한 자료를 분석한 결과, 처리 속도, 분리 집중력, 선택적 집중력은 세 가지 조건에서 유의한 차이가 있었다. 반면에 인지 평가 점수, 운전점수 감 점 및 결격은 세 가지 조건에서 유의한 차이가 없었다. 결론 : 본 연구의 결과는 20대 초보운전자의 음주운전이 인지 기능, 운전점수 감점, 운전 결격에 영향을 미치지 않았으나 처리 속도, 분리 집중력, 선택적 집중력에 영향을 미친다는 것을 보여주었다. 본 연구의 결과를 바탕으로 실제 운전 중 음주 운전자에게 예측할 수 없는 돌발 상황이 발생할 때 상당한 위험을 초래할 수 있음을 제언하는 바이다.

In this article, to solve the problems about obsolescence of parts and unable to driving turret when internal components are failure, the DC-DC boost converter in the gun/turret drive system of mobile weapon was improved. The power converting circuit in converter is changed by applying the latest components, and the control circuit is changed from analog to digital. Also, the power converting circuits were modularized in three parallel so that it could be driven even when some components failed. The improved DC-DC boost converter secured stability such as converting to voltage in a linear manner in the entire section from the start of boosting to the end. Also, through the modular configuration, turret driving system can operates when some components failed.