• International Journal of Highway Engineering
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• v.11 no.1
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• pp.187-194
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• 2009

This paper presents the development of transfer function accounting for cross-anisotropic behavior of aggregate base material for the pavement thickness design. The stress distributions predicted by nonlinear cross-anisotropic finite element program were realistic by eliminating excessive tensile stress at the bottom of the base layer and the critical pavement responses predicted by nonlinear cross-anisotropic model are higher than those predicted by linear or nonlinear isotropic models (Kim, 2004, Kim et at., 2005). Since the previously developed transfer functions such as Asphalt Institute and Chevron models, etc. were based on the critical responses obtained from linear isotropic model, those equations are not appropriate for the thickness design nonlinear cross-anisotropic base behavior. Therefore, the development of usable transfer functions for nonlinear cross-anisotropic model is ever more important. When the newly developed transfer functions were compared with AASHTO method for the thickness design, the newly developed transfer functions produce approximately 25mm reduced UAB thickness in AASHTO thickness design and this illustrates that linear isotropic model results in more conservative pavement design.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3D
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• pp.343-353
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• 2011

The unsignalized intersections in a community road in the city of Seoul have 3,753 traffic accidents(9%) of total 41,702 cases in 2008, not high in the occurrence rate of traffic accidents, but seem to have a quite high potential of accidents due to the unreasonable and insufficient operation of systems and facilities in the part of traffic foundations. In particular, the un-signalized intersections in a community road have an insufficient measure for safety as compared to the crossroads with signals, and there are few analysis of traffic accidents and domestic researches on the model of affecting factors. Our country also has no concept of passing priority in operating a crossroad without signals, differently from foreign countries, so the researches and safety measures for improving the safety of a crossroad without signals in a community road are urgent. Therefore, This study set out to analyze the road conditions, traffic conditions, and traffic environment conditions on unsignalized intersection, to identify the elements that would impose obstructions in safety, and develop a traffic accident prediction model to evaluate the safety of an unsignalized intersection using the correlation between the elements and an accident. In addition, the focus was made on suggesting appropriate traffic safety policies by dealing with the danger elements in advance and on enhancing the safety on intersection in developing a traffic accident prediction model for an unsignalized intersection.

• The KIPS Transactions:PartB
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• v.14B no.6
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• pp.445-452
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• 2007

We proposed a detection scheme of weather information in CCTV video images in this paper. The scheme obtains the RGB distribution of shiny day and divide a target image into cloud, rain, snow and for RGB distributions. shiny day RGB distribution. Our scheme designed systematically to detection and separation special characteristics of images from complex weather information. Our algorithm has less overhead than the previous methods to use weather database DB at the view of time and space. And our algorithm can be use in real world system with low cost of implementation. Also, our algorithm use informations of temperature, humidity, date, and time to detect the information of weather with high quality.

• Proceedings of the KSRS Conference
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• 2001.03a
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• pp.3-8
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• 2001

인공위성 영상이나 항공영상에서 도로를 추출하는 시스템을 구현하는 연구는 지난 20년 동안 많이 진행되어 왔다. 본 논문은 해상도가 1m-2m 정도되는 도시영상에서 직각으로 구성된 도로를 추출하는 시스템의 구현에 관한 것이다. 도시영상에서는 도시내의 가로수나 건물들이 도로를 가리게 되고, 또한 높은 건물의 그림자에 의하여 도로의 많은 부분이 가려지게 되는데, 이러한 경우에 고로를 추출할 수 있는 기법에 대하여 기술한다. 또한 도로상의 중앙 분리선이나 차선 분리선은 건물의 외곽선에 비하여 매우 약하게 나타나므로 영상에서 상대적으로 약하게 나타나는 이러한 도로의 표식을 검출하여 도로를 추출하는 기법에 대하여서도 기술한다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.2
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• pp.48-61
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• 2020

The objective of this study is to estimate traffic capacity based on the heavy-vehicle ratio in a two-lane freeway work zone where one lane is blocked by construction. For this, closed circuit television (CCTV) video data of the freeway work zone was collected, and the congestion at an upstream point was observed. The traffic volume at a downstream point was analyzed after a bottleneck was created by the blockage due to the upstream congestion. A distribution model was estimated using observed-time headway, and the road capacity was analyzed using a goodness-of-fit test. Through this process, the general capacity and an equation for capacity based on the heavy-vehicle ratio passing through the work zone were presented. Capacity was estimated to be 1,181~1,422 passenger cars per hour per lane (pcphpl) at Yeongdong, and 1,475~1,589pcphpl at Jungbu Naeryuk. As the ratio of heavy vehicles increased, capacity gradually decreased. These findings can contribute to the proper capacity estimation and efficient traffic operation and management for two-lane freeway work zones that block one lane due to a work zone.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.05a
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• pp.407-408
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• 2003

다중입력조건에 따른 단일 출력퍼지시스템인 인구밀도와 도로조건에 따른 소개속도의 모델링시스템에서는 인구밀도와 도로조건의 퍼지멤버쉽에 대한 소개속도의 상승작용을 확인할 수 있었다. 그러나 도로조건을 평가하는 방법을 포장과 비포장으로만 구분함으로 인해 발생하는 퍼지추론과정에서 비탄력성은 향후 도로조건에 대한 세밀한 조사를 통하여 퍼지멤버쉽함수의 형태를 재고해야 할 것으로 판단된다. 실제 원자력시설에서 발생할 수 있는 사고의 경우 방사능에 노출될 수 있는 일반대중은 방사능에 대한 깊은 지식을 가지지 못하는 경우가 대부분이다. 따라서 차폐효과 혹은 소개속도를 정량적으로 파악하기 힘든 경우가 많다. 따라서, 이러한 퍼지시스템은 방사선 비상대응 시스템을 개발하는 의사결정자나 비상시 방사능에 노출되는 사람들의 대응 방식을 모델링하는데 유용할 것으로 판단된다.

• The Journal of Natural Sciences
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• v.19 no.1
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• pp.65-75
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• 2008

This research was conducted to determine heavy metal contents of soil and tree in pear orchard located near national road with heavy traffics. Topsoil (0-15 cm depth) and subsoil (15-30 cm) samples in pear orchard located within 40 m from national road had higher Pb, Cu, and Zn contents than background orchard (BG) and these heavy metal contents decreased with distance from road. Topsoil samples taken at 10 m from national road had 4 times higher level in Pb, 3 times in Cu, and 2.5 times in Zn compare to BG. The Cd contents of topsoil in orchard were higher than those of BG but were not in subsoil. Highest heavy metal contents of pear leaves in roadside orchard were 20.08 in Pb, 7.02 in Cu, 30.83 in Zn, and $1.68\;mm.kg^{-1}$ in Cd and these heavy metal contents in roadside orchard were higher than BG. Cd contents of fruit and Pb contents of fruit stalk in roadside orchard were higher than BG and these heavy metal contents decreased with distance up to 40 m from the road.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.6
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• pp.214-227
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• 2021

The purpose of this study is to find the driving difficulty of automated vehicles in terms of road infrastructure operation. It was judged out of this study that the level of automated driving would be enhanced if the road situation recognition ability was advanced through the presentation of infrastructure information during the difficult driving situations. The difficulty evaluation index was divided into three stages, and a survey of experts and an AHP were conducted. The result of the AHP showed that the driving difficulty of the interrupted flow was much higher than that of the uninterrupted flow. The AHP results also showed that and the driving difficulty of unsignalized intersections and roundabouts under an interrupted flow was evaluated as the highest. The top six driving situations with high difficulty were also evaluated to occur under unsignalized intersections and roundabouts.

• Proceedings of the Korea Association of Information Systems Conference
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• 2000.05a
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• pp.195-199
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• 2000

본 논문에서는 인터넷 상의 영상에 기반한 교통 감시 시스템을 구현한다. 영상 기반의 교통 감시 시스템은 루프 감지기 등의 센서를 이용한 방법에 비해 비용과 설치, 유지, 보수면에서의 장점으로 인하여 많이 연구되고 있다. 제안한 시스템은 인터넷상에서 FPA(Field Processing Agent)와 TSM(Traffic Surveillance Manager)으로 구성되며, FPA는 TSM에게 도로 영상과 차량의 속도, 도로 점유율과 같은 교통 정보를 제공한다. 차량의 평균 속도와 도로 점유율은, 도로색 영상과 연속된 입력 영상간의 샘플링 지점의 색상 차이변화를 이용하여 추출한다. 제안한 방법은 근사적인 교통정보를 추출해 주며, 입력 영상 전체에 대한 처리 과정 없이 제한된 영역만을 처리하기 때문에, 실시간 감시 시스템을 구축하는데 용이하다.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.2
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• pp.133-142
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• 2008

Five intensive measurements of particulate PAHs were made at a roadside in Seoul from May 2005 to June 2006. The average concentration of particulate PAHs was $15.1{\pm}10.6ng\;m^{-3}$. The high concentrations of particulate fluoranthene and pyrene were observed in November 2005 due to the influence of the lower ambient temperature. Compared to the previous results at tunnel and ambient sites in Seoul, larger fraction of the high molecular PAH compounds which consist with five or six benzene rings, was observed at a roadside. This might indicate high influence of vehicle emission at a roadside. The distribution of diagnostic ratios for specific PAH compounds indicated that the influence of vehicular emission, especially diesel vehicular emission seems to be high at a roadside.