• 한국대기환경학회지
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• 제33권5호
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• pp.515-520
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• 2017

$PM_{2.5}$ concentrations were measured using a cyclone, impactor (the U.S. Environmental Protection Agency well impactor ninety-six, WINS) and optical particle counter (OPC) at a campus site located in Yongin for the period August 2014 through March 2017. The concentrations from cyclone (Y) were generally higher than those from impactor(X); the best-fit line was Y=1.22X+5.64. The ratios of $PM_{2.5}/PM_{10}$ ranged from 0.61 to 0.66 when $PM_{2.5}$ concentrations from cyclones in selected studies were converted into those from impactors using a regression equation in this study. The slope of the best-fit line between OPC and impactor was close to 1 at 0.95, while that between OPC and cyclone was 0.72. After sampling, the flow rate in the low-volume air sampler with cyclone decreased by 3% on average, which did not have a significant effect on measured concentrations.

• 한국입자에어로졸학회지
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• 제4권1호
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• pp.1-7
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• 2008

Temporal trends of the PM10 and PM2.5 mass concentrations, and the concentrations of chemical species (sulfate, nitrate, ammonium, OC, and EC) in PM2.5 at Seoul are compared with the reported results from other mega cities in the world. The mass concentrations of PM10 and PM2.5 at Seoul show decreasing trend. However, the concentration levels are still higher than other cities except Beijing. The sulfate concentration at Seoul has decreased while those of nitrate and ammonium have increased. The concentrations of OC and EC show no apparent trend.

• 한국가금학회지
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• 제48권3호
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• pp.151-160
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• 2021

본 연구는 산란계사 사육형태별 봄철의 미세먼지(PM) 및 암모니아(NH₃) 배출 농도를 측정하기 위해 수행하였다. 평사, Aviary 그리고 Cage 계사에서 미세먼지 및 암모니아 농도를 3~5월 동안 2주 간격으로 3회(24시간/회) 측정하였다. PM₁₀과 PM_2.5 농도는 24시간 동안 유사한 경향을 보였으며, 22:00부터 04:00까지 낮게 나타났다. 평사와 케이지 계사의 PM(PM₁₀, PM_2.5) 농도는 유사하게 나타났으며, 일일 편차도 심하게 보이지 않았다. 평사 계사에서는 중앙과 끝에서 24시간 동안 측정한 NH₃ 농도가 일정하게 나타났다. 측정 위치와 관계없이 평사에서 NH₃ 농도가 가장 낮게 나타났다. 평사와 Aviary 계사에서는 중앙보다 끝에서 측정된 NH₃ 농도가 더 높았으나, 케이지 계사에서는 끝에서 측정된 NH₃ 농도가 더 낮았다. 계사 주변의 PM₁₀과 PM_2.5 농도는 각각 57.5 ㎍/m³와 34.0 ㎍/m³이었다. 일평균 PM₁₀과 PM_2.5 농도는 Aviary 계사에서 4,730 ㎍/m³와 447.7 ㎍/m³로 가장 높았다. 계사 중앙과 끝의 NH₃ 농도는 케이지 계사에서 12.0 ppm과 9.31 ppm으로 가장 높았다. PM₁₀과 PM_2.5의 배출계수는 케이지에서 가장 낮았으며, NH₃의 배출계수는 가장 높았다(P>0.05). 결론적으로, PM(PM₁₀, PM_2.5) 농도는 Aviary 계사에서, NH₃ 농도는 Cage 계사에서 각각 높게 나타났다.

• Environmental Analysis Health and Toxicology
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• 제21권1호
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• pp.57-69
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• 2006

Lately human exposure to fine particles smaller than $2.5{\mu}m$ in aerodynamic diameter ($PM_{2.5}$) has become a great concern in Korea due to their possible cause of elevated mortality, lung function decrements, and more frequent hospital admissions for asthma. This study was conducted to investigate seasonal variations of human exposure to residential $PM_{2.5}$ and particle-associated polycyclic aromatic hydrocarbons (PAHs). Ten homes in Chuncheon, Korea were visited for continuous 72 hour sampling of $PM_{2.5}$ in the living rooms using a MiniVol Portable Sampler from December 22, 2002 to November 3, 2003. During the same period, outdoor $PM_{2.5}$ samples were collected on the top of the Natural Sciences Building of Kangwon National University which is located in the middle of the ten households. Samples were analyzed for $PM_{2.5}$ mass concentrations and six selected PAHs. In two smoking homes, the highest $PM_{2.5}$ concentrations were measured ranging from 51.1 to 69.7 {\mu}g/m^3$ on average in all seasons, indicating smoking is a very important contributor to the elevation of indoor particle concentrations. Seasonal comparison showed that indoor particle concentrations were higher than outdoor ones except winter. Total PAH concentrations in smoking homes were highest in winter among the seasons primarily due to low ventilation rate, followed by the outdoor site and nonsmoking homes. BaP toxic equivalents (TEQs) were calculated for five PAHs. The TEQ for smoking homes in winter was highest followed by the outdoor site in winter. It is concluded that smoking and ventilation rate are two important contributors to the elevation of indoor $PM_{2.5}$ and PAH concentrations.

• 한국환경보건학회지
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• 제34권2호
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• pp.137-147
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• 2008

This study evaluated the effects of the human activity and outdoor air on concentrations of size-selective particulate matters (PM) by conducting a realtime measurement in classrooms and on roofs at 4 elementary schools, 3 middle schools and 3 high schools in Incheon City. PM concentrations featured repetitive pattern of increasing during break time (including lunch hours) and cleaning time while decreasing during class hours. This trend was more prominent with inhalable PM and PM10 than fine PMs (PM2.5, PM1.0). The indoor/outdoor (I/O) ratio of inhalable PM and PM10 exceeded 1 while that of fine PMs was close to or below 1. The PM2.5 (out)/PM10 (out) ratio stood at 0.59 (${\pm}0.16$) and the PM2.5 (in)/PM10 (in) ratio was 0.29 (${\pm}0.09$), suggesting that occupant activity had a greater effect upon coarse particles (PM10-PM2.5) than upon fine particles (PM2.5, PM1.0). The correlations between the indoor and the outdoor PM concentrations showed a stronger positive correlation for fine particles than that of coarse particles. The linear regression analysis of PM concentrations indoor and outdoor indicated a higher determinant coefficient ($r^2>0.9$), and consistency for fine particles than in case of coarse particles. In conclusion, the results of this study suggest that the indoor coarse particle concentration is more attributed to occupant activity and the indoor fine particle concentration is more influenced by outdoor air pollution.

• 한국환경과학회지
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• 제26권9호
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• pp.1045-1055
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• 2017

Characterization of spatio-temporal variations in $PM_{2.5}$ in Gyeongnam (GN) province during 2015-2016 was investigated to assess the air quality in this area in terms of fine particles. Yearly mean concentrations of $PM_{2.5}$ ranged from 19.1 to $29.5{\mu}gm^{-3}$. High concentrations of $PM_{2.5}$ were observed in spring ($21.2-30.3{\mu}gm^{-3}$) and winter ($20.2-30.3{\mu}gm^{-3}$). Low concentrations of $PM_{2.5}$ were generally observed in fall ($16.2-23.2{\mu}gm^{-3}$). $PM_{2.5}$ concentration was highest in the morning (10 AM). The fractions of $PM_{2.5}$ in $PM_{10}$ were 0.51-0.62 and two were significantly correlated (r=0.779-0.830), suggesting common sources (fossil fuel combustion, mobile sources, etc). CO was significantly correlated with $PM_{2.5}$ in highly urbanized areas such as the city of Changwon (CW, r=0.711), compared to other air pollutants ($SO_2$, $NO_2$, and $O_3$), suggesting dominance of industrial combustion sources.

• 한국환경과학회지
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• 제31권1호
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• pp.61-76
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• 2022

In this study, surface particulate matter (PM_2.5) concentrations were calculated based on empirical equations using measurements of ceilometer backscatter intensities and meteorological variables taken over 19 months. To quantify the importance of meteorological conditions on the calculations of surface PM_2.5 concentrations, eight different meteorological conditions were considered. For each meteorological condition, the optimal upper limit height for an integration of ceilometer backscatter intensity and coefficients for the empirical equations were determined using cross-validation processes with and without considering meteorological variables. The results showed that the optimal upper limit heights and coefficients depended heavily on the meteorological conditions, which, in turn, exhibited extensive impacts on the estimated surface PM_2.5 concentrations. A comparison with the measurements of surface PM_2.5 concentrations showed that the calculated surface PM_2.5 concentrations exhibited better results (i.e., higher correlation coefficient and lower root mean square error) when considering meteorological variables for all eight meteorological conditions. Furthermore, applying optimal upper limit heights for different weather conditions revealed better results compared with a constant upper limit height (e.g., 150 m) that was used in previous studies. The impacts of vertical distributions of ceilometer backscatter intensities on the calculations of surface PM_2.5 concentrations were also examined.

• 한국대기환경학회지
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• 제32권6호
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• pp.603-612
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• 2016

The objective of this study was to estimate the emission characteristics for PM, $PM_{10}$, and $PM_{2.5}$ in the various stationary sources. The particulate matters collected in the various stationary sources such as power plants (Coal and B-C oil), incinerators(municipal and industrial waste), and glass furnaces. The PM and $PM_{10}$, PM and $PM_{2.5}$, $PM_{10}$ and $PM_{2.5}$ samples were collected using the cyclone type $PM_{10}$, $PM_{2.5}$ samplers and 30 species(19 inorganic species, 9 ionic species, OC and EC) were analyzed by ICP, IC, and TOR/IMPROVE methods. The mass concentrations of PM, $PM_{10}$, $PM_{2.5}$ from nine stationary sources ranged $0.63{\sim}9.58mg/Sm^3$, $0.26{\sim}7.47mg/Sm^3$ and $0.13{\sim}6.34mg/Sm^3$, respectively. The level of $PM_{10}$, $PM_{2.5}$ portion in PM calculated 0.63~0.99, 0.38~0.94, respectively. In the case of emission trend for species, power plant showed high concentrations for Al, Mg, Na, Si, V and $SO_4{^{2-}}$, respectively. Also, Ca, Fe, K, Si, $Cl^-$, and $K^+$ showed high in incinerator. In the case of glass furnace, Na, Pb, K, Si, $Na^+$ and $SO_4{^{2-}}$ represented high concentrations. Power plant showed higher EC/OC concentrations than other sampling sites. These results suggest the possible role for complement establishment process of emission inventory and emission management for PM.

• Asian Journal of Atmospheric Environment
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• 제11권4호
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• pp.313-321
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• 2017

$PM_{10}$ and $PM_{2.5}$ were collected at the Gosan Site on Jeju Island from 2013 to 2015, and their ionic and elemental species were analyzed to examine the variations in their chemical compositional characteristics related to different meteorological conditions. Concentrations of nss-$SO_4{^{2-}}$ and $NH_4{^+}$ were respectively 6.5 and 4.7 times higher in the fine particle mode ($PM_{2.5}$) compared to the coarse particle mode ($PM_{10-2.5}$), however $NO_3{^-}$ concentrations were 2.4 times higher in the coarse mode compared to the fine particle mode. During Asian dust days, the concentrations of nss-$Ca^{2+}$ and $NO_3{^-}$ increased to 8.2 and 5.0 times higher in $PM_{10}$, and 3.5 and 6.0 times higher in $PM_{2.5}$, respectively. During haze days, the concentrations of secondary pollutants increased by 3.1-4.7 and 3.2-7.9 in $PM_{10}$ and $PM_{2.5}$, respectively, and they were, respectively, 1.2-2.1 and 0.9-2.1 times higher on mist days. The aerosols were acidified largely by sulfuric and nitric acids, and neutralized mainly by ammonia in the fine particle mode during the haze days, but neutralized by calcium carbonate in coarse particle mode during the Asian dust days. Clustered back trajectory analysis showed that concentrations of nss-$SO_4{^{2-}}$, $NO_3{^-}$, and $NH_4{^+}$ were relatively high when air masses travelled from China.

• Asian Journal of Atmospheric Environment
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• 제2권1호
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• pp.68-74
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• 2008

We briefly show the results of indoor and personal $PM_{2.5}$ measurements in an epidemiologic study designed to evaluate the health risks of ambient $PM_{2.5}$ in Japan and the relationship between indoor and outdoor PM concentrations. The impact of indoor and outdoor PM pollution on health is described based on one morbidity study. The results of other studies on indoor $PM_{2.5}$ measurements are also described.