• Title/Summary/Keyword: Air pollution dispersion

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A Study on the Dispersion of Air Pollutants in Local Circulation of Mesoscale (중규모 국지 순환에서 대기 오염 물질의 확산에 관한 연구)

  • 이화운;오은주
    • Journal of Environmental Science International
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    • v.3 no.1
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    • pp.39-47
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    • 1994
  • Dispersion characteristics of air pollutants in the mountainous coastal area are investigated in considering with the mesoscale local circulations using a two dimensional numerical model with two kinds of topograpy of 500m and 300m. In the model, land-sea breezes and mountain-valley wind are mainly considered under the condition of the absence of large scale prevailing flow in the circulation analysis, and the pollutants dispersion is traced by the Lagrangian methods. According to the results, the wind velocity is affected by topography and is stronger in the case of 500m height mountain than that of 300m, the Pollutants that source is near the coast transported over the mountain and dispersed to behind inland area. It is classified that the topography change control affects the wind velocity and the circulations. The pollutants that source is different transported and concentrated to behind inland and/or diffused to the sea area by the combination of the wind system with topographic changes. The results can be applied to the air pollution control with the arrangement design of industrial area and the planning of coastal developments.

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Assessment of Air Pollution and Estimation of Emission from Incheon International Airport by EDMS (EDMS를 이용한 인천국제공항의 대기오염 배출량 산정과 주변지역에 미치는 영향 평가)

  • Lee, Seong-Yong;Jang, Young-Kee
    • Journal of Environmental Impact Assessment
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    • v.11 no.2
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    • pp.67-77
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    • 2002
  • Air traffic increased 12% annually in Korea since 1988 after the Olympics, this rate is two times than the rate of the world average. In order to accommodate fast growing aviation demand, Incheon International Airport is operated at Yongjong Island since March, 2001. The Incheon airport project will continue till 2020. After the final phase in 2020, Incheon International Airport will handle 100 million passengers, 530,000 flights and 7 million tons of cargo annually. In this study, air pollution from aircraft and other sources are calculated and assessed in Incheon International Airport area by EDMS(Emission and Dispersion Modeling System), which is a combined emission and dispersion model for airport. EDMS could also be considered power plant, incinerator and aircraft support equipment such as ground support equipment, aerospace ground equipment, auxiliary power units. And EDMS is recommended as preferred model for air quality assessment of the airport area by U.S. EP A. The result of this study shows that NOx emission from aircraft and support utility is estimated as 27,000 - 35,000 ton/yr and Namdong-Gu area in Incheon city is affected as 30-60 ppb by the NOx emission from these sources in 2020, the final phase of Incheon international airport construction.

Air Pollution Monitoring in Taiwan: An Application of Tethersonding in Coastal Central Taiwan

  • Cheng Wan-Li;Hsu C. H.;Huang J. D.;Shi J. L.
    • Journal of Environmental Health Sciences
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    • v.31 no.3
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    • pp.215-220
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    • 2005
  • The atmospheric transportation and dispersion processes of air pollutants are important issues in dealing with air pollution problems. Air pollutants originated from biological and anthropogenic activities are not only limited to the local emission sources, but could also be transported and dispersed to other regions by synoptic weather systems. Besides, the complexity of topography of central Taiwan helps accumulating air pollutants to promote high-concentration episodes. The techniques of tethersonding were applied to monitor the vertical profiles of winds, air temperatures and humidity, as well as to collect air samples, to be analyzed for pollutants $(O_3,\;NO_2,\;NO\;and\; NMHC)$ from the ground up to 1000m. A time period of about one week, 19-26 October 2002, was chosen as the sampling period due to the high frequency of episode occurrence in autumn based on the past records. Associating with the analysis of weather patterns, the atmospheric characteristics over high-concentration areas can be resolved in more detail. The result of the tethersonding studies showed that weak northerly sea breeze (with thickness about 300m) with low wind speed (about 1 to 2 m/sec) could help develop high ozone concentrations in the down-wind areas. It is also important to have a built-up aloft of precursors and ozone to develop high concentration on the previous day.

Air Pollution Monitoring in Taiwan: An Application of Tethersonding in Coastal Central Taiwan

  • Cheng, Wan-Li
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2005.06a
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    • pp.184-210
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    • 2005
  • The atmospheric transportation and dispersion processes of air pollutants are important issues in dealing with air pollution problems. Air pollutants originated from biological and anthropogenic activities are not only limited to the local emission sources, but could also be transported and dispersed to other regions by synoptic weather systems. Besides, the complexity of topography of central Taiwan helps accumulating air pollutants to promote high-concentration episodes. The techniques of tethersonding were applied to monitor the vertical profiles of winds, air temperatures and humidity, as well as to collect air samples, to be analyzed for pollutants ($O_3,\;NO_2$, NO and NMHC) from the ground up to 1000 m. A time period of about one week, 19 -26 October 2002, was chosen as the sampling period due to the high frequency of episode occurrence in autumn based on the past records. Associating with the analysis of weather patterns, the atmospheric characteristics over high-concentration areas can be resolved in more detail. The result of the tethersonding studies showed that weak northerly sea breeze (with thickness about 300 m) with now wind speed (about 1 to 2 m/sec) could help develop high ozone concentrations in the down-wind areas. It is also important to have a built-up aloft of precursors and ozone to develop high concentration on the previous day.

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Characteristics of Exhaust Emissions from a Heavy-duty Diesel Engine (대형디젤엔진의 오염물질 배출특성)

  • 엄명도;류정호;이종태;임철수
    • Transactions of the Korean Society of Automotive Engineers
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    • v.7 no.9
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    • pp.20-27
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    • 1999
  • The proportion of diesel vehicle is very high in this country . PM and NOx emitted from diesel-posered vehicle is severely ;affecting to be air quality . Especially, diesel particulate matters(DPM) including black smoke are hazardous air pollutants to human health and environment. In order to reduce the exhaust emissions from diesel engines, it is necessary to analyze the characteristics of exhaust emissions from diesel engines in various driving conditions. Recently, there are occasion to increase the fuel consumption rate to engine power up. So, in this study we have tested a diesel engine detached from in use -diesel vehicle and analyzed exhaust emission by driving condition and fuel dispersion rate. From this results, we will prepare the comprehensive management plan for exhaust emissions from diesel vehicles and contribute to the improvement of air pollution in urban area.

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Lagrangian Particle Dispersion Model Based on Non-equilibrium Level 2.5 Closure Model in the Convective Boundary Layer (열대류 경계층에서 비평형 2.5 난류모델을 기초로 한 라그란지안 입자 확산 모델)

  • 구윤서
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.04a
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    • pp.167-168
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    • 2000
  • 복잡한 구조를 갖고 시간에 따라서 변하는 바람장내에서 공장굴뚝과 같은 점오염원에서 배출되는 오염물질의 확산을 계산하기 위해서 라그란지안 입자확산모텔(Lagrangian Particle Dispersion Model, LPDM)을 사용하는 것이 최근의 연구 동향이다. 구윤서(1999a, 1999b)는 중립 및 안정한 대기조건에서 바람장 계산시 비평형 2.5 난류모델을 이용한 LPDM을 개발하여 복잡한 대기흐름내 확산현상을 보다 정확히 모사할 수 있는 LPDM을 제시하였다. (중략)

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Comparison between the Road-based and the Parcel-based Address Coordinates for Urban Air Pollution Estimation - A Case Study of Yeongdeungpo-gu, Seoul, Korea - (도심대기오염추정을 위한 도로명주소좌표와 지번주소좌표의 비교 - 서울 영등포 지역의 사례연구 -)

  • Park, Jinwoo;Choi, Jinmu;Hong, Seong-Yun
    • Journal of Cadastre & Land InformatiX
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    • v.46 no.2
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    • pp.169-181
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    • 2016
  • The address system in Korea was changed to the road-based system in 2014, but the current address coordinates are still largely based on the old, parcel-based system. Compared to the parcel-based address system that defines the center of a parcel as its coordinates, the road-based system locates the coordinates at a certain distance away from the road on which the parcel fronts. The difference in coordinates between these two systems is small, but it can be crucial for micro-level modelling. In order to assess the impact of the discrepancy between the two address systems, this study measured the degree of air pollution exposure at two different locations, the road-based address coordinates and the parcel-based address coordinates, for each of 252 buildings in Yeongdeungpo-gu, Seoul. The air pollution values were estimated using a microscopic air pollution dispersion model, CALINE4, and t-tests and F-tests were conducted to evaluate statistical significance on the observed difference. The results showed a considerable difference in the level of air pollution exposure between the two address systems, suggesting that the on-going use of the parcel-based address coordinates could cause potentially significant errors in micro-level analysis.