PURPOSES : In this study, the existence of an optimal pattern among transition methods applied during changes in traffic signal timing was investigated. We aimed to develop this pattern into an artificial intelligence reinforcement-learning model to assess its effectiveness METHODS : By developing various traffic signal transition scenarios and considering 19 different traffic signal transition situations that can be applied to these scenarios, a simulation analysis was performed to identify patterns through statistical analysis. Subsequently, a reinforcement-learning model was developed to select an optimal transition time model suitable for various traffic conditions. This model was then tested by simulating a virtual experimental center environment and conducting performance comparison evaluations on a daily basis. RESULTS : The results indicated that when the change in the traffic signal cycle length was less than 50% in the negative direction, the subtraction method was efficient. In cases where the transition was less than 15% in the positive direction, the proposed center method for traffic signal transition was found to be advantageous. By applying the proposed optimal transition model selection, we observed that the transition time decreased by approximately 70%. CONCLUSIONS : The findings of this study provide guidance for the next level of traffic signal transitions. The importance of traffic signal transition will increase in future AI-based traffic signal control methods, requiring ongoing research in this field.
PURPOSES : This study aims to improve pedestrian safety by analyzing the effectiveness of displaying the remaining time of red crosswalk signal that provide pedestrians with information regarding the time available for crossing METHODS : This study analyzes the effectiveness of newly installed displays for remaining time of the red pedestrian signal in the cities of Yeongcheon and Yeongju in Gyeongsangbuk-do. The data collection was divided into periods before and after the installation of the facilities. Pedestrian departure delays were measured at the introduction and subsequent stages of installation, and changes in pedestrian behavior were quantitatively analyzed. Statistical significance of the results was verified using a t-test. RESULTS : For the displays of remaining time of crosswalk red signals installed in Yeongju, the pedestrian departure loss time decreased from 3.36 seconds before installation to 1.85 seconds after installation. Additionally, compared to the pre-installation situation, the postinstallation situation showed a relatively lower standard deviation, indicating that the pedestrians exhibited a more consistent pattern when starting to cross. Similarly, for the displays of remaining time of crosswalk red signal installed in Yeongcheon, the pedestrian departure loss time decreased from 2.37 seconds before installation to 1.89 seconds after installation. As in Yeongju, the post-installation situation showed a relatively lower standard deviation, indicating that the pedestrians exhibited a more consistent pattern when starting to cross. CONCLUSIONS : In this study, we verified the effect of newly installed pedestrian countdown signals on improving pedestrian safety at two intersections in Yeongcheon and Yeongju, which were selected through a survey of traffic accident-prone areas in Gyeongsangbuk-do. Pedestrian countdown signals were quantitatively confirmed to have a positive impact on pedestrian safety. Based on the observations, it is anticipated that expanding the installation of these signals will have a positive effect on pedestrian safety, particularly in areas with frequent traffic accidents and the senior and children protection zones. Results of this study indicate that the proposed policy measures are expected to strengthen pedestrian safety and reduce traffic accidents.
우리나라에서는 「모빌리티 혁신 및 활성화 지원에 관한 법률」을 제정하여 전국적으로 첨단모빌리티 사업을 활성화할 수 있는 틀 을 마련하였다. 그러나 모빌리티혁신법 내 첨단모빌리티 수단이 이용하는 친화적 도로설계에 대한 가이드라인이 부재한 상황이다. 본 연구에서는 모빌리티혁신법 내 제9조 ‘첨단모빌리티 친화적 도로환경 조성’의 원활한 사업 시행을 위해 디지털 인프라를 중심으로 가 이드라인을 제안한다. 친화적 도로를 이용하는 첨단모빌리티 도로 대상을 선정한 후 이를 토대로 요구되는 디지털 인프라를 고려하였 다. 디지털 인프라는 도로에 대한 정보를 디지털화 하는 것을 목적으로 설정하여 ① 디지털 도로, ②디지털 관리, ③디지털 트윈 3가 지로 구분지어 가이드라인을 제시하였다. 이는 지방자치단체에서 첨단모빌리티 사업 시행 시 필수적으로 고려해야 할 인프라를 검토 할 수 있을 것이다
우리나라는 교통사고 사망자수 감축을 위해 다양한 교통안전 개선사업을 지속적으로 추진하고 있다. 특히, 보행자 안전 강화를 위한 보행환경개선사업은 중앙정부 및 지방정부를 중심으로 시설, 제도, 교육ž홍보 등 다양한 방법으로 수행되고 있다. 최근 횡단보도 보행자 안전 강화를 위한 시설 개선 사례로 활주로형 횡단보도가 설치ž운영되고 있다. 활주로형 횡단보도는 야간에 운전자 시인성을 증진하고 보행자의 안전성을 확보하는 시설물이다. 그러나 신규로 설치되는 활주로형 횡단보도의 정량적인 보행안전 개선 효과에 대한 연구는 부 족하다. 본 연구에서는 보행환경개선사업을 통해 읍․면지역에 신규 설치되는 활주로형 횡단보도의 효과를 시설물 접근로 진입 차량 평 균 주행 속도 조사를 통해 분석하였다. 총 8개 지점의 활주로형 횡단보도를 대상으로 접근로 진입 차량 평균 주행 속도를 조사하였으 며, 평균 속도 감소율은 15.3%이고, 속도 최대 감소율은 27.4%로 나타나는 것으로 분석되었다. 이와 같이 무단횡단이 빈번이 관측되는 읍․면지역의 경우 활주로형 횡단보도의 설치함으로써 접근하는 차량의 속도를 저감시키는 것으로 확인하였다. 향후 보행자 교통사고 저감이 필요한 읍․면지역에 설치 시 긍정적인 효과를 기대할 수 있을 것으로 사료된다
PURPOSES : This study aims to develop and validate timing transition techniques for real-time traffic signal operations, departing from conventional methods based on past commuting traffic patterns. METHODS : In this study, we propose two traffic signal transition techniques that can perform transitions while minimizing disruptions within a short period. The Proposed 1 technique involves an unconditional transition within one cycle and allows for the allocation of offset changes to both the coordinated and non-coordinated phases. The Proposed 2 technique performs transitions within 1-2 cycles based on the offset change rate and considers the non-coordinated phase for allocating offset changes. RESULTS : Functional improvements of the proposed techniques were validated. For validation, simulated traffic signal transition scenarios were created, and a comparative analysis of the transition techniques was performed based on the selected analysis approaches. The results showed that the Proposed 1 technique exhibited the lowest delay during the approximated saturated transitions, whereas the Subtract technique showed the lowest delay during the non-saturated transitions. CONCLUSIONS : These findings emphasize the importance of selecting and applying appropriate transition techniques tailored to individual traffic scenarios. The proposed transition techniques provide valuable insights for improving real-time traffic signal operations, and contribute to the overall efficiency and effectiveness of traffic management in highway corridors.
PURPOSES : This study analyzes the effectiveness of different types of children's safety devices in a school zone. The analysis targets are yellow carpet type A (installed up to the floor and wall) and yellow carpet type B (installed only on the floor).
METHODS : Based on field data collected at a school zone in Seoul, statistical tests were conducted to compare three different pairs of data: (1) none vs. yellow carpet type A, (2) none vs. yellow carpet type B, and (3) yellow carpet types A and B. The test employed two different measures: (1) the level of drivers’ eye attention and (2) the level of the vehicle deceleration rate. The study utilized software named "Visual Attention Software" to quantify the level of drivers’ eye attention at the location where children pedestrians were waiting for a green signal. It also utilized the Vegas (pro 17) image processing software to reduce the cruising speed data frame-by-frame from the video streaming data. The image data used in this study were collected with (1) camcorders attached to a test vehicle and (2) a drone aerial imaging technique.
RESULTS : It was found that the level of the drivers’ eye attention level improved in the daytime when either of yellow carpet types A and B was placed; moreover, the safety enhancement effects were statistically identical. However, in nighttime, the measures only improved when the yellow carpet type A was placed. It was learned that yellow carpet type A provides significant safety effects according to both measures, i.e., the level of drivers’ eye attention and cruising speed.
CONCLUSIONS : The test results suggest that the yellow carpet type A should be installed in school zones to maximize the safety effects of yellow carpets.
PURPOSES : In this paper, pedestrian-oriented time assured traffic operation (POTATO), adopted in Korea at a single crossing pedestrianoriented operating area, is explored and applied to a simulation experiment and test site to verify the operation efficiency.
METHODS : Three candidate plans are presented as a method to operate pedestrian-oriented signal operations that can overcome the restrictions on signal controllers in Korea. The selected POTATO and TOD signal operations were compared and analyzed. The delay and pedestrian queues, present length, and number of times were used as comparative indices.
RESULTS : Scenario-specific simulations confirmed that the delay, compared to TOD signal operation, was reduced by up to 5 s/ped depending on the vehicle traffic volume and the number of pedestrians. For the vehicle delay, the results increased up to 8.99 s/veh, depending on the traffic volume of the vehicles and pedestrians. As a result of the test site operation, POTATO operation improved by 5.12 s/ped (approximately 46.69% improvement) compared to TOD operation in the hours commuting to school and by 2.84 s/ped in the hours commuting from school (approximately 51.13% improvement). In case of vehicle delay, the delay increased by 2.35 s/veh (approximately 64.39%) in the hours commuting to school and 1.20 s/veh (approximately 21.11%) in the hours commuting from school compared to the TOD operation.
CONCLUSIONS : Through simulations and test site pilot operation verifications, the effects of pedestrian delay improvement were more positive if POTATO proposed in this study was low in vehicle traffic.
PURPOSES : This paper is to deliver an engineering design guide currently unavailable that highway engineers can refer to when they need to determine the safe distance between the starting point of the underground highway in a metropolitan area and the access points of the adjacent highway.
METHODS : The distance between two different highway points should be sufficiently far to support the number of lane changes that drivers may take comfortably at the cruising speed in critical traffic conditions.
RESULTS : The proper distance for the selected case study is calculated to be 160 and 200 m at the cruising speeds of 40 km/h and 50 km/h, respectively, without significant increase in potential conflicts estimated by the combination of the VISSIM and SSAM analysis.
CONCLUSIONS : The proposed design method can be referred in urban metropolitan areas where no specific design guide is yet available, and it would prevent the unnecessary increase in construction costs and encourage private-public partnership highway businesses.
PURPOSES: This paper presents the development and evaluation of the smart hardware-in-the-loop systems (SMART-HILS) that evaluate traffic signal operations of a new real-time traffic signal control system called SMART SIGNAL at the traffic management center (TMC) level.
METHODS: The layouts of the hardware and software components of the SMART-HILS were introduced in this study and its performance was tested using real-time traffic signal operation algorithms embedded in the SMART SIGNAL control server by utilizing the VISSIM simulation model. In this study, the SMART-HILS management software was developed using .NET programming language. Fewer random seed numbers were used for the test scenarios by conducting statistical tests to address the shortcomings of a longer time due to the adoption of the simulation time as the real-time by the TMC server.
RESULTS : It was determined that SMART-HILS can communicate with TMC and VISSIM for both upload and download directions within acceptable time constraints and evaluate new design algorithms for traffic signal timing.
CONCLUSIONS : In practice, traffic engineers can utilize SMART-HILS for testing the traffic signal operation alternatives before their selection and implementation. This application could increase the productivity of traffic signal operation.
PURPOSES : In this study, analyze the characteristics of IOC indicator 'threshold' which is needed when evaluating the traffic signal operation status with ESPRESSO in various grade road traffic environment of Seoul metropolitan city and derive suggested value to use in field practice. METHODS : Using the computerized database program (Postgresql), we extracted data with regional characteristics (Arterial, Collector road) and temporal characteristics (peak hour, non-peak hour). Analysis of variance and Duncan's validation were performed using statistical analysis program (SPSS) to confirm whether the extracted data contains statistical significance. RESULTS: The analysis period of the main and secondary arterial roads was confirmed to be suitable from 14 days to 60 days. For the arterial, it is suggested to use 20 km/h as the critical speed for PM peak hour and weekly non peak hour. It is suggested to use 25 km/h as the critical speed for AM peak hour and night non peak hour. As for the collector road, it is suggested to use 20 km/h as the critical speed for PM peak hour and weekly non peak hour. It is suggested to use 30 km/h as the critical speed for AM peak hour and night non peak hour.
CONCLUSIONS : It is meaningful from a methodological point of view that it is possible to make a reasonable comparative analysis on the signal intersection pre-post analysis when the signal operation DB is renewed by breaking the existing traffic signal operation evaluation method.
최근 국내에서 교통운영체계 개선 사업이 활성화 되어 시행되고 있다. 운전자 안전 및 운전지원 서비스 개선을 신호운영을 통해 도출해 내려는 움직임이 활발해졌다. 이러한 노력의 성과를 이해하기 위한 다양한 평가방법이 활용되어 왔다. 그러나 이러한 평가 방식은 조사원에 의한 현장 주행 조사가 평가 방식의 대부분이었으며, 주관적 요인이 간섭되는 방식이다. 상기 시스템으로부터 탈피하기 위하여, 객관적인 교통정보 이력자료를 활용하는 ‘혼잡강도(Intensity of Congestion; IOC)’ 지표를 활용하는 신호교차로 운영 평가방법이 연구되나, 혼잡강도 지표 값을 결정하는 ‘분석 기간과 임계 속도’에 대한 공학적 지침이 부족하다. 본 논문은 시간적 특성과 지역적 특성을 반영한 도로 등급별(주간선도로, 보조간선도로) 분석을 적용하여 ‘혼잡 강도’ 지표 내 임계값을 제안하는 연구 내용을 전달한다. 본 연구에 사용된 자료는 5분 단위로 누적된 2016년 서울특별시 TOPIS 링크별 교통소통 속도자료이다. 상기 자료를 분석을 위해 데이터베이스 프로그램을 사용하여 ‘혼잡강도’ 지표 내 임계값을 변환하며 신호교차로 운영상태 개선 전과 후 일정 기간 교통소통 이력자료를 비교하는 분석을 수행하였다. 본 연구에서는 임계속도 값으로 10 km/h, 15 km/h, 20 km/h, 25 km/h, 30 km/h를 고려하였다. 분석 기간으로 신호교차로 운영상태 개선 전 1일, 7일, 14일, 30일, 60일을 적용하였고 분석 일마다 오전, 오후첨두시와 주간, 야간비첨두시로 분류 분석을 수행하였으며, 분석 대상 교차로로 서울특별시 강남권, 강북권의 신호교차로를 선정하여 시공간적 특성을 반영한 연구를 수행하였다. 일원분산분석 및 던컨 검증분석에 의하여 분석 기간 설정에 따른 대표 임계속도를 분석한 결과는 다음과 같다. 통계 분석 결과, 주간선도로의 오전, 오후 첨두시간의 경우 25 km/h와 20 km/h를 임계속도로 사용하는 것이 효율적이었다. 주간 비첨두시간과 야간 비첨두 시간은 1일의 경우 15 km/h와 30 km/h를 사용하는 것이 효율적이었으며 7일, 14일, 30일, 60일의 경우 20 km/h, 25 km/h, 30 km/h를 사용하는 것이 효율적인 것으로 나타났다. 보조 간선도로의 오전 점두시간은 1일의 경우 25 km/h를 사용하는 것이 효율적이었으며 7일, 14일, 30일, 60일의 경우 30 km/h를 사용하는 것이 효율적이었다. 오후 첨두시간, 주간 비첨두시간의 경우 20 km/h 임계속도로 사용하는 것이 효율적이었다. 야간 비첨두시간의 경우 30 km/h를 임계속도로 사용하는 것이 효율적이었다. 본 연구 결과를 바탕으로 신호운영 및 신호교차로 평가에 대한 연구가 추가적으로 이루어져야 할 것이다.
1. 우리나라 쌀 소비량은 지속적으로 감소하고 있으나 쌀 가 공식품의 매출은 꾸준히 증가하는 추세에 있다. 2. 이에 본 연구는 농촌진흥청 농식품 소비자 패널조사 자 료(703가구)를 이용하여 최근 5년간 쌀 가공식품 구매패턴의 변화를 파악하고자 하였다. 이를 위하여 쌀 가공식품을 밥류, 죽류, 면류, 떡류, 방류, 과자류, 주류, 음료류, 조미류, 가루류 10종류로 분류하고, 쌀 가공식품의 종류별, 월별, 구매장소별 구매가구 수, 구매금액, 구매빈도 등 전반적인 구매패턴의 변 화를 살펴보았다. 3. 향후 소비 증가가 예상되는 쌀 가공식품의 종류와 향후 요구되는 관련 연구과제를 제안하였다.