• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.20 no.5
• /
• pp.100-112
• /
• 2021

With the advent of big data, traffic prediction has been developed based on historical data analysis methods, but this method deteriorates prediction performance when a traffic incident that has not been observed occurs. This study proposes a method that can compensate for the reduction in traffic prediction accuracy in traffic incidents situations by hybrid approach of machine learning and traffic simulation. The blind spots of the data-driven method are revealed when data patterns that have not been observed in the past are recognized. In this study, we tried to solve the problem by reinforcing historical data using traffic simulation. The proposed method performs machine learning-based traffic prediction and periodically compares the prediction result with real time traffic data to determine whether an incident occurs. When an incident is recognized, prediction is performed using the synthetic traffic data generated through simulation. The method proposed in this study was tested on an actual road section, and as a result of the experiment, it was confirmed that the error in predicting traffic state in incident situations was significantly reduced. The proposed traffic prediction method is expected to become a cornerstone for the advancement of traffic prediction.

• Journal of Korean Society of Transportation
• /
• v.24 no.3 s.89
• /
• pp.167-176
• /
• 2006

An minimum path algorithm for integrated networks with departure time constraints require considering arrival time of arriving mode, transfer time. waiting time, and departure time of next mode. Integrated network with diverse modes commonly include departure time constraints. Because public mode suck as train and airplane have fixed service schedule which provide passengers. This study developed the k-path algorithm in integrated network with time varying conditions and departure time constraints. We proposed the extended method based on entire path deletion method, and examined the application of the proposed algorithm through case study.

• Journal of Korean Society of Transportation
• /
• v.19 no.6
• /
• pp.161-170
• /
• 2001

Vehicle detection is the basic of traffic monitoring. Video based systems have several apparent advantages compared with other kinds of systems. However, In video based systems, shadows make troubles for vehicle detection. especially active shadows resulted from moving vehicles. In this paper a new method that combines background subtraction and edge detection is proposed for vehicle detection and shadow rejection. The method is effective and the correct rate of vehicle detection is higher than 98(%) in experiments, during which the passive shadows resulted from roadside buildings grew considerably. Based on the proposed vehicle detection method, vehicle tracking, counting, classification and speed estimation are achieved so that traffic information concerning traffic flow is obtained to describe the load of each lane.

• Journal of Korea Spatial Information System Society
• /
• v.3 no.1 s.5
• /
• pp.63-73
• /
• 2001

The purpose of this study is to develop a method of integrating diverse communication networks for effectively providing ITS(Intelligent Transport System) services. In this paper, in oder to integrate communication networks, we have defined ITS services, its requirements and functions of communications. Also, we have analyzed the six important ITS services in the National ITS Architecture along with the characteristics of wireless communications. Based on the ITS service scenarios, we have derived the communication methods for ITS services.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2018.10a
• /
• pp.49-51
• /
• 2018

미국과 중국 그리고 일부 유럽국가에서는 교통혼잡 해결하기 위해 2인 이상 탑승한 차량만 운행 가능한 다인승 전용차로(HOV, High Occupancy Vehicle Lanes)를 도입하여 운영하고 있다. HOV를 도입한 도시에서는 나 홀로 운행 차량이 많이 감소 되어 교통 혼잡 문제를 조금이나마 해결 할 수 있었다. 현재 HOV에서는 차량 내부의 탑승 인원수를 확인하기 위한 시스템을 사용하고 있다. 기존의 해당 시스템은 HOV에 지나간 차량을 자동으로 적외선 카메라를 통해 촬영하여 사람이 직접 검수하는 방식이다. 기존 방식은 사람이 직접 검사하는 방식이라 이를 위한 많은 인력과 시간이 소모되는 점, 그리고 사람마다 확인한 결과가 다를 수 있는 등 여러 가지 단점이 있다. 본 논문에서는 기존 HOV의 차량 내부 탑승 인원 확인 기술의 여러 단점을 극복하기 위해 Deep Learning과 Computer Vision을 이용한 새로운 기술 설계를 위한 연구한 내용을 다룬다.

• Journal of Korean Society of Transportation
• /
• v.26 no.5
• /
• pp.91-100
• /
• 2008

Pedestrians are exposed to accidents as a result of the lack of understanding the meaning of a flashing green signal. This study was to designed to relate changes of pedestrians' crossing characteristics as a functions of flashing green signal timings. A field survey was conducted to collect pedestrian preference and safety and it was examined by signal operation experiment. Two versions of new pedestrian signal timings were compared to the existing pedestrian signal timings. The results indicated that the number of pedestrians who starts to cross during flashing green signals was significantly decreased when flashing green signals started at 1/2 or 2/3 point of crossing. However, the number of pedestrians who remain in the crossing during red signals was significantly increased when flashing green signals started at 2/3 point of crossing. This study concludes that starting flashing green signals at 1/2 point of crossing is the safest. Also, implication and directions for its practical relevance were discussed.

• Journal of Korean Society of Transportation
• /
• v.20 no.4
• /
• pp.27-38
• /
• 2002

VTIS(Value-added Traffic Information System), among the sub-systems of ATIS, is an Advanced Traffic System which innovates efficiency and safety. And this system, having marketability and publicness, is very important. Moreover, This system offers definite traffic information according to the demand of specified users. And it is expected to produce additional spread effects because of high participation rate of private sector. However, the VTIS service media are varied and there are varied optimal Prices and payment methods according to each medium. Because of that, there needs the study on these problems or optimal criteria. But because existing studies were devoted to estimate the optimal route, the study toward the optimal price which was considered part of user and service use demand do not exist. Accordingly, we surveyed under imaginary alternative pricing scenarios and forecasted the use demand of VTIS by using Binary Logit model. Also, for the users who answered that they would use VTIS service in survey, we classified their use's behaviors as four categories and estimated the use ratio to each category by using Ordered Probit model. Last, using sensitivity analysis for results form above, we derived the optimal price that is 2800won in monthly. 145won in payment per call. Then, VTIS service use rate is respectively 65%, 75%.

• 한국도로학회지:도로
• /
• v.10 no.2
• /
• pp.58-67
• /
• 2008

교통량이 많은 도심지내 장대 지하차도 건설은 교통정체 해소에 기여를 하지만 초기 공사비가 많이 소요되는 단점이 있다. 또한, 화재등 유고시 이용자의 안전을 최우선으로 고려되어야 한다. 즉, 장대 지하차도 건설에 있어서 경제성과 안전성이 함께 만족할 수 있는 건설 방안이 필요하다. 세종지하차도는 이러한 문제점을 극복하고자 다음과 같이 지하차도의 환기방식 및 단면, 포장형식, 사고 예방 및 발생시를 대비한 종합방재시스템을 구축하였다. $\cdot$환기방식은 종류식 환기방식의 경제성과 횡류식 환기방식의 제연성능을 겸비할 수 있는 조합형 환기방식과 Duct Arch 단면을 적용하여 공사비 절감 및 운영시 유지관리비를 획기적으로 절감하였다. $\cdot$지하차도 포장형식은 화재시 내화성이 우수하며 유독가스 발생이 없는 HPC(고성능 콘크리트 포장) 포장을 적용하여 이용자의 안전을 최우선으로 고려하였고 일반 아스팔트 포장 및 배수성 아스팔트 포장에 비해 우수한 성능과 공용수명을 가진 공법을 적용함으로서 유지보수비용의 절감을 가능하게 하였다. 또한, 콘크리트포장의 단점인 소음발생을 최소화하기 위해 타이닝과 그루빙을 적용하였다. $\cdot$지하차도내 화재 등 유고시 신속한 대피가 가능하도록 피난 연락문 간격을 167m 간격으로 설치하고 비상탈출계단 6개소를 확보하였다. 또한 노약자 및 환자의 지하차도 외부로 대피를 돕기 위해 비상엘리베이터 3개소를 설치하는 등 사고발생 시 종합적으로 대처할 수 있는 시스템을 마련하여 적용하였다.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.22 no.1
• /
• pp.311-326
• /
• 2023

This paper proposes a plan to improve the installation and operation of traffic safety facilities using a microscopic simulation by confirming the difference in the perception method and range of autonomous vehicles and human vehicles. In this study, the existing 『Traffic Safety Sign Installation·Management Guidelines』 was reviewed, and safety signs among traffic safety facilities were classified according to changes in vehicle behavior. Subsequently, for the classified facilities, the installation location of the traffic sign was changed through simulation experiments, and the optimal location was inferred to suggest an improvement plan. This study confirmed how traffic safety facilities installed based on the visibility of human drivers affect road efficiency and safety in mixed traffic flow with autonomous vehicles and human-controlled vehicles. The optimal location derived through this study is meaningful because it can be used as the basis for revising the guidelines on the installation and management of traffic safety facilities.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.21 no.5
• /
• pp.183-196
• /
• 2022

Public transportation accessibility has been evaluated through minimum level of service for public transportation. However it is evaluated based operators rather than users. This study analyzed the users' accessibility(first-mile, last-mile) to public transportation using altteul transport card data. As a result of user's accessibility of public transportation, rural areas was lower than that in the urban areas. This study calssified type 1 and 2 based average approach time, and average approach time of Type 1 and 2 were more than average approach time of total area. We propsed an efficient introduction of autonomous public transportation on-demand service using delphi survey. As a result of delphi survey, experts agreed on 9 items regarding function, service item, route operation, approach distance, route mileage, punctuality.