• Journal of Korean Society for Atmospheric Environment
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• v.9 no.4
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• pp.278-287
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• 1993

In order to calssify smog type durnig the summer season in Seoul, air Quality and meterorological data were analyzed by multivariate analysis. Among 15 variables relating to visibility, 10 variables were selected by multiple regression analysis for clustering of smog types; total suspended particle, sulfur dioxide, ozone, ntrogen dioxide, total hydrocarbon, south-north wind component, ralative humidity, precipitable water, mixing height and air temperature. Somg types were grouped into three clusters using cubic clustering criterion and the mumbers of days in each cluster were contained 74, 28 and 16 days. Each cluster was seperated clearly by sulfur dioxide, precipitable water and air teperature. The first cluster was representative of high ozone concentration and prevailing meterological conditions for ozone formation. Therefore, visibility in the first cluster was considered to be affected by photochemical smog. The third cluster showed characteristics of sulphurous smog type due to the higher concentration of primary pollutant, based on the dry condition than that in another cluster. On the other hand, the characteristic of the second cluster was not relatively clear, but considered to be in an intermediate characteristic between photochemical smog and sulphurous smog type.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.4
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• pp.437-449
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• 2003

A multi-functional indoor smog chamber was designed and evaluated to investigate photochemical or water vapor reaction mechanisms of air pollutants. Various smog chamber experiments could be conducted using ambient air or purified air in this smog chamber. The smog chamber consisted of a housing, a Teflon bag, blacklights, injection ports, sampling ports, and utility facilities. The characteristics of light source, the wall losses of air pollutants, and the quality of purified air were experimentally investigated. The maximum NO$_2$ photolysis rate was 1.10 min$^{-1}$ . In a 2.5-m$^3$ Teflon bag, the wall losses of ambient $O_3$, NO, and NO$_2$ were 1.2~2.4$\times$10$^{-3}$ min$^{-1}$ , 0.7~2.0$\times$10$^{-3}$ min$^{-1}$ , and 0.4~2.0$\times$10$^{-3}$ min$^{-1}$ , respectively. The wall loss of ambient particles ranging 0.05 to 0.2 ${\mu}{\textrm}{m}$ was 1.8~5.4$\times$10$^{-3}$ min$^{-1}$ , which was slightly higher than those of ambient gaseous species. The purified air supply system provided high quality of air with NO$_{x}$ < 1 ppb, and total hydrocarbons < 5 ppb.b.

• Journal of the korean Society of Automotive Engineers
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• v.8 no.4
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• pp.1-12
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• 1986

대기오염의 역사는 산업의 발전과 그 맥락을 같이 한다. 자동차가 대기오염의 한 Source로 주목 을 받기 시작한 것은 1940년대초 LA의 극심한 Smog발생의 원인을 찾으면서 부터이며, 1950년대 에 와서 Haagen Smit박사에 의해 Photo Smog의 Mechamism이 해석되면서 Smog를 유발하는 HC, NOx는 자동차 배출 Gas가 50% 이상을, 유해한 CO는 90%이상을 기여한다는 것이 파명되 어, 1965년 미국 California주에서 자동차에 대한 배출 Gas규제가 최초로 시작되었다. 자동차 배출 Gas로서 규제대상은 HC(타화수소), CO, NOx(질소산화물)이며, 엔진 Crankcase Emission(Blow-by Gas), Tail pipe로부터 배출되는 Exhaust Emission, 그리고 연료 Tank, 기 화기등의 연료계로부터 배출되는 Evaporative Emission에서의 HC, CO, NOx 각 상한치를 규제 하고 있다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.135-136
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• 2002

최근 들어, 대도시 지역에서 오존(O$_3$)농도가 환경기준을 초과하는 빈도가 증가함에 따라 대기 중 광화학 대기오염현상과 그에 따른 오존 등 2차 광화학 오염물질에 대해 많은 관심이 집중되고 있다. 이러한 복잡한 대기중의 반응을 이해하고 해석하기 위하여 Smog Chamber를 이용한 대기 중 광화학 반응 연구가 진행 중에 있으며, 국내에서도 연구가 이루어지고 있다 Smog Chamber를 통해 대기 중의 광화학 반응의 세부적인 이해와 수학적 모델에 필요한 화학반응들의 변수를 제공하는 등 포괄적이고 종합적인 연구를 수행할 수 있다. (중략)

• Journal of environmental and Sanitary engineering
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• v.6 no.1
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• pp.109-120
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• 1991

This paper briefly reviews our knowledge concerning the potential health risk of smog. It includes a review of the meteorological phenomenon, the causes of death in different age groups from London smog which occurred during the week of December 5, 6, 7, 8, 1952. During the London disaster, which caused 4,000 excess human deaths, it was deternimed the meteorological factors of almost absence of wind, low temperature, high humidity and an inversion. Hence, at ground level of air pollutants were suddenly increased and attributed to the combined action of a particulate matter with sulfur dioxide. As a result, abnormally large numbers of persons died especially, those individuals already suffering from disease of the respiratory and cardiovascular systems.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.3
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• pp.183-190
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• 1993

For the efficient control of photochemical smog materials, the researches on the change patterns of photochemical smog precursors are indispensable. In this study, a time-series analysis was performed for the auto-monitoring data of Kwanghwamun and Jamsil stations in 1990, and the change patterns of photochemical smog materials were studied. Especially, auto-correlation coefficients were analyzed to investigate the cyclic characteristics of pollutants in question and cross-correlation coefficients to investigate the correlations between pollutants adjusted for time lag and between $O_3$ and meteorological factors. Results of researches are as follows: First, in the case of NO and $NO_2$ intimately related to human activities, 12-hour cycle was prevalent. But $O_3$ showed 24-hour cycle. Second, NO showed a relatively high correlation with $O_3$ and usually developed into $O_3$ 5 to 7 hours later. Third, temperature, insolation intensity, and wind speed showed a positive correlation with $O_3$ while relative humidity a negative correlation.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.171-172
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• 2002

대기중의 2차 광화학 반응을 포함하는 대기중의 반응을 이해하고 해석하기 위하여 Smog Chamber를 이용한 대기중 광화학 반응연구가 활발히 진행 중에 있으며, 국내에서도 연구가 이루어지고 있다 이러한 연구들은 고농도 수준에서 광화학 반응 메커니즘에 중점을 두고 있는 것으로 실제 대기의 농도수준에서 광화학반응에 관한 연구자료는 미흡한 실정이다. 또한, 서울지역의 경우 광화학 스모그의 대표적인 경우에 해당하는 LA Smog의 경우와 비교할 때 습도가 높으며, 대기 중 먼지의 농도 또한 비교적 높다고 볼 수 있으며 이러한 서울지역의 광화학 스모그 특성을 규명하기 위하여 기초연구라 할 수 있는 Smog Chamber 연구가 필요하다. (중략)

• Journal of Korean Society for Atmospheric Environment
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• v.32 no.2
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• pp.131-157
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• 2016

A smog chamber has been an effective tool to study air quality, particularly secondary organic aerosol (SOA), which is typically formed by atmospheric oxidation of volatile organic compounds (VOCs). In controlled environments, smog chamber studies have validated atmospheric oxidation by identifying, quantifying and monitoring products with state-of-art instruments (e.g., aerosol mass spectrometer, scanning mobility particle sizer) and provided chemical insights of SOA formation by elucidating reaction mechanisms. This paper reviews types of smog chambers and the current state of smog chamber studies that have accomplished to find pathways of SOA formation, focusing on gas-particle partitioning of semivolatile products of VOC oxidation, heterogeneous reactions on aerosol surface, and aqueous chemistry in aerosol waters (e.g., cloud/fog droplets and wet aerosols). For future chamber studies, then, this paper discusses potential formation pathways of fine particles that East Asia countries (e.g., Korea and China) currently suffer from due to massive formation that gives rise to fatal health problems.

• Journal of Environmental Science International
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• v.14 no.2
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• pp.231-240
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• 2005

The number of cases exceeding environmental standards of atmospheric ozone in the major cities in Korea has steadily increased during the past decades. In order to understand and analyze the atmospheric reactions in the atmosphere, especially the secondary photochemical reactions, smog chambers studies have been performed very actively by many research groups worldwide. However, these studies have focused on the mechanism of photochemical reactions in high concentration conditions, not at the ambient levels. Therefore, in-depth studies in these conditions are essentially needed to realize exact mechanism in the atmosphere near the earth surface, especially at Korean atmospheric conditions. In this experiment, the mechanism of photochemical smog was examined through a comparative experiment of smog chambers under sun light and black light conditions. The results of our study indicated that concentrations of ozone, aldehyde, and PAN increased as the radiation of light source increases. Photochemical reaction patterns can be considered quite similar for both black light and sun light experiments. Based on our experiments using toluene as a reactant which is present at significant high levels in ambient air relative to other VOCs, it was found that toluene could contribute notably to oxidize NO to $NO_2$, this reaction can eventually generate some other photochemical oxidants such as ozone, aldehyde, and PAN. The results of simulation and experiments generally showed a good agreement quite well except for the case of $O_3$. The restriction of oxidization of NO to $NO_2$ seems to cause this difference, which is mainly from the reaction of peroxy radical itself and other reactants in the real gas.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.1
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• pp.51-60
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• 1993

In order to study on the cause of visibility aggravation, we have selected the days of low-visibility observed in Seoul with haziness that was below 6km from 12 to 15 LST. According to the examinations, the number of low-visibility days satisfying the criteria is 30 days in 1989, 39 days in 1990, and 35 days in 1991, respectively. The annual number of low visibility days appears to increase mainly due to an increase in emission of air pollutants and in anthropogenic water vapor in the biosphere. The relationship between visibility and air pollutants(TSP, $NO_2, SO_2, O_3$) of selected days is also studied. Air pollution concentrations of selected days are much higher than those of other days. It is observed that the cause of visibility aggravation in Seoul is mainly smog and air pollutants. In particular, the visibility reduction and high $SO_2$ concentrations at Seoul in winter are similar phenomena that occurring with London smog, while the visibility reduction and high $O_3$ concentrations at Seoul in summer are also similar to the type of Los Angeles smog.