• Korean Journal of Remote Sensing
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• v.20 no.2
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• pp.77-89
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• 2004

The spatial and temporal variations of aerosol optical depth (AOD) over Northeast Asia regions have special importance in the aerosol research for estimation of aerosol radiative forcing parameters and climate change. Aerosol optical and physical properties (AOD and ${\AA}$ngstrom parameter) have been investigated by using Moderate Resolution Imaging Spectroradiometer (MODIS) and Total Ozone Mapping Spectrometer (TOMS) Aerosol Index (AI) to estimate aerosol characteristics over the study region during 2001. Additionally, aerosol characteristics over the Korean peninsular during Aerosol Characteristic Experiment in Asia (ACE-Asia) Intensive Observation Period (IOP) have been investigated by using satellite observations. The results showed that the daily-observed aerosol data indicate seasonal variations with relatively higher aerosol loading in the spring and very low during the winter. The typical Asian dust case showed higher AOD (>0.7) with lower Angstrom exponent (<0.5) and higher AI (>0.5) that is mainly due to the composition of coarse particles in the springtime. Mean AOD for 2001 at 4 different places showed 0.65$\pm$0.37 at Beijing, 0.31$\pm$0.19 at Gosan, 0.54$\pm$0.26 at Seoul, and 0.38$\pm$0.19 at Kwangju, respectively. An interesting result was found in the present study that polluted aerosol events with small size dominated-aerosol loading around the Korean peninsular are sometimes observed. The origin of these polluted aerosols was thought to East China. Aerosol distribution from satellite images and trajectory results shows the proof of aerosol transport. Therefore, aerosol monitoring using satellite data is very useful.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.47-48
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• 2001

It is well known that atmospheric aerosols play an important role in the radiation balance of the earth and meteorological processes as well as in atmospheric chemistry. Aerosols may origin from both natural and/or anthropogenic sources. Thus, the chemical composition of aerosols can vary considerably. For example, the chemical composition of marine aerosol has been the subject of a considerable number of investigations, including the evaluation of long-range transport of anthropogenic constituents on the chemistry of the remote marine boundary layer. (omitted)

• Particle and aerosol research
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• v.15 no.4
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• pp.191-202
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• 2019

In this study, performance (particle removal efficiency and breathing resistance) of several commercially available face masks (electrostatic filter masks (KF80 certified), a nanofiber filter mask (KF80 certified), and an uncertified mask) with their filter structure and composition were evaluated. Also, effects of relative humidity (RH) of incoming air, water and alcohol exposure, and reusability on performance of face masks were examined. Monodisperse and polydisperse sodium chloride particles were used as test aerosols. Except the uncertified mask filter, PM_2.5 removal efficiency was found to be higher than 90%, and the nanofiber filter mask had the highest quality factor due to the low pressure drop and high removal efficiency (nanofibers were arranged in a densely packed pore structure and contained a significant amount of fluorine in addition to carbon and oxygen). In the case of the KF80 certified mask, the removal efficiency was little affected when the RH of incoming air increased. When the mask filters were soaked in water, the removal efficiency of mask filters was degraded. In particular, the uncertified mask filter showed the highest removal efficiency degradation (26%). When the mask was soaked in alcohol, the removal efficiency also decreased with the greater degree than the water soaking case. The nanofiber mask filter showed the strongest resistance to alcohol exposure among tested mask filters. During evaluation of reusability of masks in real life, the removal efficiency of certified mask filter was less than 4% for 5 consecutive days (2 hours per day), while the removal efficiency of uncertified mask filter significantly decreased by 30% after 5 days.

• Particle and aerosol research
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• v.17 no.4
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• pp.91-106
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• 2021

Daily PM_2.5 was collected during summer period in 2020 in Gwangju to investigate its chemical and light absorption properties. In addition, real-time light absorption coefficients were observed using a dual-spot 7-wavelength aethalometer. During the study period, SO₄^2- was the most important contributor to PM_2.5, accounting for on average 33% (10-64%) of PM_2.5. The chemical form of SO₄^2- was appeared to be combination of 70% (NH₄)₂SO₄ and 30% NH₄HSO₄. Concentration-weighted trajectory (CWT) analysis indicated that SO₄^2- particles were dominated by local pollution, rather than regional transport from China. A combination of aethalometer-based and water-extracted brown carbon (BrC) absorption indicated that light absorption of BrC due to aerosol particles was 1.6 times higher than that due to water-soluble BrC, but the opposite result was found in absorption Ångström exponent (AAE) values. Lower AAE value by aerosol BrC particles was due to the light absorption of aerosol BrC by both water-soluble and insoluble organic aerosols. The BrC light absorption was also influenced by both primary sources (e.g., traffic and biomass burning emissions) and secondary organic aerosol formation. Finally the ATR-FTIR analysis confirmed the presence of NH₄⁺, C-H groups, SO₄^2-, and HSO₄^2-. The presence of HSO₄^2- supports the result of the estimated composition ratio of inorganic sulfate ((NH₄)₂SO₄) and bisulfate (NH₄HSO₄).

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.05a
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• pp.131-132
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• 2004

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.49-49
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• 2001

제주도 고산에서는 2000년 3월 23일∼5월 4일 기간 동안에 동북아지역 대기중 에어로졸의 물리화학적 특성과 분포 및 대기환경변화에 대한 영향을 파악하기 위하여 국제공동관측 연구사업인 ACE(Aerosol Characterization Experiments)-Asia Program에 참여하여 대기중 에어로졸 특성을 연구하였다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.121-122
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• 2001

황사의 발생과 이동은 대기미량물질의 장거리이동 현상 가운데 우리에게 가장 익숙한 것일 것이다. 우리나라는 동북아시아의 동쪽에 위치한 지역으로, 사계절 중 여름을 제외한 때의 주풍향이 서풍인 지역이다. 특히, 봄철에는 편서풍의 영향이 크다. 따라서 우리나라는 봄에 몽골이나 중국북부의 사막이나 황토지대에서 불어오는 황사의 영향을 불가피하게 받게 된다. (중략)

• Journal of Korean Society for Atmospheric Environment
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• v.17 no.6
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• pp.487-492
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• 2001

In this technical information, the springtime TSP measurement data between 1993 and 1996 at Kosan are presented. Based on the data, it was found that the concentrations of crustal species increase when Yellow Dust phenomenon occurs. Among anthropogenic species, the concentration of Pb and NO$_3$$^{[-10]}$ increase when Yellow Dust phenomenon occurs. Further research agenda are discussed to study the effects of Yellow Dust.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.6
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• pp.803-810
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• 2004

Water contents in fine particles at Seoul and Gosan are estimated by using a gas/particle equilibrium model, SCAPE (Simulating Composition of Atmospheric Particles at Equilibrium). Also, sensitivity of particulate inorganic ionic concentrations on the total ionic species is estimated. Water content at Gosan is more sensitive to ambient relative humidity (RH) than Seoul. At both sites water content is most sensitive to sulfate concentration among sulfate, nitrate, and ammonium. Solid salts levels and compositions are also studied.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.391-392
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• 1999

한반도를 포함한 동아시아 지역은 북미, 유럽과 더불어 세계 3대 산성우 다발지역으로 꼽히고 있고 최근 들어 산업화와 인구증가, 에너지소비의 증가로 인한 대기오염물질의 배출량이 크게 증가하고 있으며, 배출원 오염물질의 국가간 장거리 이동에 많은 관심이 모아지고 있다. 본 연구에서는 동북아시아의 대표적인 청정지역 제주도 1100고지 PM$_{10}$ 에어로졸의 농도를 분석하고, 각 데이터와 기상관측자료와의 비교를 통하여 배경지역에서의 에어로졸 특성을 조사하였다.(중략)