• 한국대기환경학회지
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• 제31권6호
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• pp.562-572
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• 2015

$NO_x$ emissions from diesel vehicles have been regarded as a main cause of high $NO_2$ concentration in metropolitan area. Recent studies have shown that the on-road $NO_x$ emissions of diesel vehicles are quite higher than the emission limits specified with the pre-defined test method for emission certification. To reduce air pollutants effectively, the discrepancy of emissions in certification and real-driving conditions should be tackled. In this study, the real-driving emissions have been estimated with portable emission measurement system (PEMS). The results of this study have shown that the on-road $NO_x$ emissions from diesel vehicles have been decreased as the introduction of stricter emission regulation, EURO-6, but additional reduction should be still required and robust technologies should be applied to control $NO_x$ in real-driving conditions. RDE-LDV (Real Driving Emission - Light Duty Vehicles) test method being developed in the European Union can represent excessive on-road $NO_x$ emissions of diesel vehicles as applied emission technologies and can be a solution to remove discrepant $NO_x$ emissions between certification and Korean real-driving conditions. Among the $NO_x$ reduction technologies for EURO-6 diesel vehicles, selective catalytic reduction (SCR) system has shown the better performance than lean $NO_x$ trap (LNT) system to control on-road $NO_x$ emissions. Implementing RDE-LDV will require vehicle manufacturers to adopt the more effective $NO_x$ reduction technology in real driving conditions.

• Asian Journal of Atmospheric Environment
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• 제9권2호
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• pp.146-157
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• 2015

Emissions of ozone precursors ($NO_x$ and VOCs) and photochemical ozone creation potentials (POCPs) of VOC emission sources were investigated in the largest port city (i.e., Busan), Korea during the year 2011. This analysis was performed using the Clean Air Policy Support System (CAPSS) national emission inventory provided by the National Institute of Environmental Research (NIER), Korea. For $NO_x$, the emissions from off-road mobile sources in Busan were the most dominant (e.g., $31,202ton\;yr^{-1}$), accounting for about 60% of the total $NO_x$ emissions. The emission from shipping of off-road mobile sources (e.g., $24,922ton\;yr^{-1}$) was a major contributor to their total emissions, amounting to 47% of the total $NO_x$ emissions due to the port-related activities in Busan. For VOCs, the emission source category of solvent usage was predominant (e.g., $36,062ton\;yr^{-1}$), accounting for approximately 82% of the total VOC emissions. Out of solvent usages, the emission from painting was the most dominant ($22,733ton\;yr^{-1}$), comprising 52% of the total emissions from solvent usages. The most dominant VOC species emitted from their sources in Busan was toluene, followed by xylene, butane, ethylbenzene, n-butanol, isopropyl alcohol, and propane. The major emission sources of toluene and xylene were found to be painting of coil coating and ship building, respectively. The value of POCP for the off-road mobile source (61) was the highest in ten major activity sectors of VOC emissions. Since the POCP value of ship transport of off-road mobile source (72) was also high enough to affect ozone concentration, the ship emission can play a significant role in ozone production of the port city like Busan.

• 한국환경생태학회지
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• 제21권1호
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• pp.47-54
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• 2007

본 연구는 광릉 지역의 활엽수 천연림과 도로 주변에서 서식지 구조와 조류군집의 특성을 파악하기 위해 2005년 10월부터 2006년 8월 사이의 기간 동안 수행되었다. 활엽수 천연림과 도로 지역의 서식지 환경은 매우 큰 차이가 있는 것으로 나타났다. 활엽수 천연림은 대경목의 비율이 높고 상층 임관이 잘 발달해 있는 반면, 도로에서는 소경목이 대부분을 차지하였으며, 상층임관의 발달이 적은 반면 하층식생의 피도가 높았다. 계절별 조사 결과 활엽수 천연림에서는 모두 37종의 조류가 관찰되었으며, 도로에서는 20종이 기록되었다. 4계절에 있어서도 활엽수 천연림 이 도로보다 관찰 종수, 개체수 및 종다양도에 있어서 모두 높은 것으로 나타났다. 또한 길드 구조에 있어서도 활엽수 천연림 지역에서는 수관층 및 수동(나무구멍)에서 먹이와 둥지를 얻는 조류들이 많이 관찰되었으며, 도로에서는 관목이나 지면을 이용하는 조류가 많이 기록되었다. 두 지 역은 인접해 있음에도 불구하고 조류 군집의 특성에 있어서 큰 차이를 보였다. 이러한 차이는 두 지 역 간 서식환경의 차이와 깊은 연관이 있는 것으로 판단된다.

• 한국ITS학회 논문지
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• 제21권4호
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• pp.50-61
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• 2022

눈, 비, 안개, 미세먼지는 차량 운전자의 시야를 방해하고 이는 안전거리 미확보와 속도 편차의 증가를 야기하여 반복적인 대형 교통사고의 원인이 되고 있다. 본 연구에서는 안개, 눈, 비, 온도, 습도, 풍향, 풍속, 일사량, 기압, 미세먼지, 강수량 등 11종류를 측정할 수 있는 보급형 국산 도로환경센서를 개발하였으며, 기존에 상용되고 있는 안개 가시거리 센서로부터 측정된 가시거리와 개발 센서의 적외선 송·수신부를 통해 측정된 적외선 신호값을 비교하여, 두 측정값의 관계를 도출하였다. 기존 안개 가시거리 센서와 개발센서 측정값의 관계는 도로 안전에 직접적 영향을 미치는 500m 이하의 가시거리에서 측정된 데이터를 대상으로 도출되었다. 개발센서의 적외선 신호값과 기준 센서에서 도출된 가시거리의 비교 결과, 통계적으로 두 데이터 간 상관관계가 매우 높은 것으로 분석되었으며, 개발 센서의 적외선 신호값을 활용하여 안개 가시거리를 기준 센서와 매우 유의한 수준으로 추정할 수 있는 것으로 판단된다.

• 한국분무공학회지
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• 제21권4호
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• pp.207-213
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• 2016

To protect air pollution of urban area from motor vehicles, emission limits for diesel vehicles have been dramatically lowered in short period. But recent studies have shown that on-road NOx emissions of light-duty diesel vehicles are considerably higher than the values measured with laboratory test procedures used for emission certification. To tackle with this issue, Ministry of Environment have a plan to introduce EU RDE-LDV (Real-driving Emission-Light-duty Vehicle) regulation. In this study, 4 Euro 6 diesel vehicles have been tested with the new test procedures published by EU to estimate on-road NOx emissions using PEMS (Portable Emission Measurement System). The results have shown that the requirements of EU RDE-LDV could be met in driving condition of metropolitan area for constitution of test routes and validity of test results. In analysing with Moving Averaging Window method the completeness and normality of test data were validated with the requirement. On-road NOx emissions were quite deviated as test vehicles and higher than the new limit of on-road NOx emission enforced from Sept. 2017, which means that RDE-LDV can effectively reduce NOx emission of diesel vehicles in real driving conditions of Korea.

• 한국지반환경공학회 논문집
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• 제19권7호
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• pp.13-18
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• 2018

최근 도심지를 중심으로 도로함몰이 증가하고 있어 시민들의 안전을 위협하고 있다. 도로 하부에는 상하수도관로, 전기통신시설 등 각종 도로시설물이 매설되어 있는데 이 시설물의 노후화가 도로 함몰의 원인으로 작용하고 있다. 특히, 도로함몰의 주된 원인으로 주목받고 있는 노후 하수관의 경우 단순히 매설연도에 의존하여 하수관 교체 및 보수보강 등의 관리가 이뤄지고 있으며, 하수관 상태에 의한 도로함몰의 위험성은 고려되지 않는 실정이다. 따라서, 본 연구에서는 다양한 하수관 제원 및 주변 환경 정보 및 CCTV 탐사 결과 및 GPR 탐사 결과를 고려한 신뢰성 있는 도로함몰 위험도 평가 방안을 제시하고자 하였다.

• 대한임베디드공학회논문지
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• 제11권5호
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• pp.313-323
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• 2016

With the development of autonomous vehicle, there has been active research on advanced driver assistance system for road marking detection using vision sensor and 3D Laser scanner. However, vision sensor has the weak points that detection is difficult in situations involving severe illumination variance, such as at night, inside a tunnel or in a shaded area; and that processing time is long because of a large amount of data from both vision sensor and 3D Laser scanner. Accordingly, this paper proposes a road marking detection and classification method using single 2D Laser scanner. This method road marking detection and classification based on accumulation distance data and intensity data acquired through 2D Laser scanner. Experiments using a real autonomous vehicle in a real environment showed that calculation time decreased in comparison with 3D Laser scanner-based method, thus demonstrating the possibility of road marking type classification using single 2D Laser scanner.

• 제어로봇시스템학회논문지
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• 제22권10호
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• pp.803-810
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• 2016

This paper presents a study of localization methods based on particle filter using 2D laser sensor measurements and road feature map information, for autonomous vehicles. In order to navigate in an urban environment, an autonomous vehicle should be able to estimate the location of the ego-vehicle with reasonable accuracy. In this study, road features such as curbs and road markings are detected to construct a grid-based feature map using 2D laser range finder measurements. Then, we describe a particle filter-based method for accurate positional estimation of the autonomous vehicle in real-time. Finally, the performance of the proposed method is verified through real road driving experiments, in comparison with accurate DGPS data as a reference.

• 한국전자통신학회논문지
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• 제8권11호
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• pp.1647-1654
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• 2013

실외 도로에서의 차량 검출 성능은 기상 상태, 태양 이동에 의한 그림자, 조도 변화 등에 영향을 받는다. 본 논문에서는 낮 시간대의 실외도로에서 이러한 주변 환경변화에 강건한 배경 추정 알고리즘과 연동한 차량 검출 시스템을 제안한다. 배경 추정 알고리즘은 혼합 가우시안 모델을 적용하고 후보 영역에 대한 차량 검출은 Adaboost 알고리즘을 적용하였다. 흐린 날, 비오는 날 등 동일한 실제 도로에서 서로 다른 기후에 획득한 CCTV 비디오 영상을 사용한 실험을 통해 제안하는 방법이 일반 도로에서의 차량 검출에 유용한 것을 확인하였다.

• 한국소음진동공학회논문집
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• 제17권3호
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• pp.274-281
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• 2007

Road traffic noise is not produced by any one factor rather it occurs as a composition of various factors. Its occurrence is made by running engine noise, tire frictional, and exhaust noise etc. The quality of the noise depends on the size of the vehicles, rotation and engine speed, vehicle load, package state of the road and incline etc. The occurrence of any noise level of heavy trucks appears louder than smaller vehicles and the noise levels produced differs according to speed and load etc between similar size vehicles. Other factors such as traffic density, average speed, mixing rate of heavy vehicles, and the distance between vehicles also generate road traffic noise. In this paper we examine 2, 4, and 6-lane roads in Jeonju. Consequently, this study examines the means used to measure road traffic noise. It was found that when there is a large traffic density and the average velocity is below 70 km/h, the noise level could receive a relative proper value by the current measuring means. But in the case of night-time, it was found that the current measuring method is inapposite.