• 한국대기환경학회지
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• 제20권2호
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• pp.263-276
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• 2004

According to the annual emission estimates of U.S.A., fugitive dust, the particulate matter entrained in the ambient air which is caused from man-made or natural activities such as movement of soil, vehicles, equipments and windblown dust, contributes 90% of PM$_{10}$ emission. In spite of an importance of fugitive dust emission in PM$_{10}$ estimation, it is excluded in the national emission inventory of Korea so far. In this paper, an emission inventory of fugitive dust for each region and in major cities throughout the country, which is the first time in Korea these values have been compiled, is presented. Sources of fugitive dust emission have been classified into paved/unpaved roads, construction operations, agricultural operations, and natural sources. The emission factors of the existing fugitive dust emission were reassessed in a way that significantly improved the reliability of the estimated result. The Korea's first national emission inventory of fugitive dust by administrative districts proposed in this paper would provide scientific reference data for establishing an reduction strategy of PM$_{10}$ and preparing effective control measures, and would contribute to academic achievement in the atmospheric environments field and the establishment of CAPSS (Clean Air Policy Support System).stem).

• Asian Journal of Atmospheric Environment
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• 제9권1호
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• pp.12-21
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• 2015

Air pollution is a challenging issue in some of the large cities in developing countries. In this regard, data interpretation is one of the most important parts of air quality management. Several methods exist to analyze air quality; among these, we applied the Multilayer Perceptron (MLP) and Radial Basis Function (RBF) methods to predict the hourly air concentration of benzene in 14 districts in the municipality of Tehran. Input data were hourly temperature, wind speed and relative humidity. Both methods determined reliable results. However, the RBF neural network performance was much closer to observed benzene data than the MLP neural network. The correlation determination resulted in 0.868 for MLP and 0.907 for RBF, while the Index of Agreement (IA) was 0.889 for MLP and 0.937 for RBF. The sensitivity analysis related to the MLP neural network indicated that the temperature had the greatest effect on prediction of benzene in comparison with the wind speed and humidity in the study area. The temperature was the most significant factor in benzene production because benzene is a volatile liquid.

• 한국대기환경학회지
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• 제11권3호
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• pp.245-252
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• 1995

Atmospheric aerosols were collected by a High Volume Tape Sampler from March 1992 to December 1993 ar Korean, Cheju, Korea. The water soluble ion concentrations in aerosol were analyzed. The concentrations of cations (N $a^{+}$, $K^{+}$, $Ca^{2+}$, $Mg^{2+}$, N $H_{4}$$^{+}$) were determined by an Inductively Coupled Plazma(ICP) or an Atomic Absorption Spectrometer(AAS), and those of anions (C $l^{[-10]}$ , N $O_{3}$$^{[-10]}$ , S $O_{4}$$^{2-}$) were analayzed by the capillary electrophoresis method. The $Ca^{2+}$, S $O_{4}$$^{2-}$ and N $O_{3}$$^{[-10]}$ concentrations in spring were higher than those in other seasons. The lowest concentrations of these elements were found in summer, largely due to scavenging by frequent rains. Especially the $Ca^{2+}$ concentration on April was three to four times higher than the annual mean concentration. The enrichment factor(E.F.) of each element was calculated. The annual mean E.F. values of the $Ca^{2+}$, $Mg^{2+}$ and C $l^{[-10]}$ in 1992 were the same as those in 1993 except $k^{+}$ and S $O_{4}$$^{2-}$. The correlation formula between all cations and anions for the whole period was Anions = 0.759 * Cations + 0.066.Cations + 0.066.

• Journal of Microbiology
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• 제44권3호
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• pp.269-275
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• 2006

Atmospheric-pressure cold plasma (APCP) using helium/oxygen was developed and tested as a suitable sterilization method in a clinical environment. The sterilizing effect of this method is not due to UV light, which is known to be the major sterilization factor of APCP, but instead results from the action of reactive oxygen radicals. Escherichia coli, Staphylococcus aureus, and Saccharomyces cerevisiae deposited on a nitrocellulose filter membrane or Bacillus subtilis spores deposited on polypropylene plates were exposed to helium/oxygen plasma generated with AC input power at 10 kHz, 6 kV. After Plasma treatment, nitrocellulose filter membranes were overlaid on fresh solid media and CFUs were counted after incubation overnight. D-values were 18 sec for E. coli, 19 sec for S. aureus, 1 min 55 sec for S. cerevisiae, and 14 min for B. subtilis spores. D-values of bacteria and yeast were dependent on the initial inoculation concentration, while the D-value of B. subtilis spores showed no correlation. When treated cells were observed with a scanning electron microscope, E. coli was more heavily damaged than S. aureus, S. cevevisiae exhibited peeling, and B. subtilis spores exhibited shrunken morphology. Results showed that APCP using helium/oxygen has many advantages as a sterilization method, especially in a clinical environment with conditions such as stable temperature, unlimited sample size, and no harmful gas production.

• 대한화장품학회지
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• 제22권2호
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• pp.76-88
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• 1996

The facial color is affected by age increase, health condition, internal and/or external environment factors and so on. Especially, the external environment factors in accordance with the influence of environment pollution that is air pollution, exert a bad influence of skin. The object of this study shall be quantified the facial color change in accordance with age increase, external environment factors. Therefore we have make the measurement about the facial color change of Korean women by regional groups. We've quantified through correlation equation, the rate of the many external environment factors which influence the facial color change (air pollution, climate condition, season etc.) As the result of the study, we have reach to know that CO, $O_3$, $NO_2$ has high relation with hue, value, chrome change. The facial color change is proved to be influenced atmospheric environment condition. Besides in hue and value in relation with meteorology demonstrates its link with the temperature, the evaporation quantity, the duration of sunshine of each region. Therefore we have instill cognition of the environmental pollution in accordance with external environment factor that was quantified. And we have reach to know this study affects cosmetics development of new concept.

• 한국대기환경학회지
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• 제31권1호
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• pp.63-71
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• 2015

The gaseous and particulate emissions from agricultural crop residues burning were investigated. The test residues included white soybean stem, pepper stem, apple branch, peach branch, pear branch, grape branch, sesame stem, perilla stem, and barley stem. Particulate emissions were dominated by fine particles (< $0.1{\mu}m$ in size). The highest $PM_{2.5}$ Emission factors were from barley stems (35.2 g/kg), and the lowest from pepper stems (7.9 g/kg). Emission factors for CO, NO, and VOCs were 146~305 g/kg, 4.94~15.02 g/kg, 27.4~353.3 g/kg, respectively. Benzene played an important role in VOCs emissions from biomass burning.

• Asian Journal of Atmospheric Environment
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• 제9권1호
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• pp.86-90
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• 2015

Temperature was considered to estimate the minimum detectable absorption coefficient of aerosol particles from photothermal spectroscopy. Light energy absorbed by subsequent emission from the aerosol results in the heating of the aerosol sample and consequently causes a temperature change as well as changes in thermodynamic parameters of the sample. This thermal effect is the basis of photothermal spectroscopy. Photothermal spectroscopy has several types of techniques depending on how the photothermal effects are detected. Photothermal interferometry traces the photothermal effect, refractive index, using an interferometer. Photoacoustic spectroscopy detects the photothermal effect, sound wave, using a microphone. In this study, it is suggested that the detection limit for photothermal spectroscopy can be influenced by the introduction of a slip correction factor when the light absorption is determined in a high temperature environment. The minimum detectable absorption coefficient depends on the density, the specific heat and the temperature, which are thermodynamic properties. Without considering the slip correction, when the temperature of the environment is 400 K, the minimum detectable absorption coefficient for photothermal interferometry increases approximately 0.3% compared to the case of 300 K. The minimum detectable absorption coefficient for photoacoustic spectroscopy decreases only 0.2% compared to the case of 300 K. Photothermal interferometry differs only 0.5% point from photoacoustic spectroscopy. Thus, it is believed that photothermal interferometry is reliably comparable to photoacoustic spectroscopy under 400 K.

• 한국대기환경학회지
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• 제14권6호
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• pp.631-642
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• 1998

Fall-out particles were collected by the modified British deposit gauges at 35 sampling sites in Suwon area from January to November, 1996. Twenty chemical species (Al. Ba, Cd, Cr, K, Pb, Sb, Zn, Cu, Fe, Ni, V, F-, Cl-, NO3-, 5042-, Na+, NH4+, Mg2+, and Ca2+) were analyzed by AAS and If. The purposes of this study were to estimate qualitatively various emission sources of the fell-out particle by applying multivariate statistical techniques such as factor analysis, multiple regression analysis, and discriminant analysis. During the study, outlier sites were determined by a z-score method. Cl-, Na+, Mg2+, and SO42- were highly correlated due to their common marine related source. Wind speed was the most influential factor for the deposition fluxes of the particle itself and all the chemical species as well. When applying the factor analysis, 8 source patterns were qualitatively obtained, such as marine source, soil source, oil burning source, Cr related source, tire source, Cd related source, agriculture source, and F- related source. As a result of the multiple regression analysis, we could suggest that some chemical compounds may possibly exist in the form of CaSO4, NaN03, NaCl, MgC12, (NH4)2SO4, NaF, and CaCl2 in the fall-out particles. Finally, spatial and seasonal classification study performed by a discriminant analysis showed th.at SO42-, Ca2+, Cl-, and Fe were dominant in the group of spatial pattern; however, SO42-, Cl-, Al, and V were in the group of seasonal pattern.

• Asian Journal of Atmospheric Environment
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• 제4권3호
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• pp.150-156
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• 2010

Inter-comparison of chemical transport models (CTMs) was conducted among four modeling research groups. Model performance of the ensemble approach to $O_3$ and $PM_{2.5}$ simulation was evaluated by using observational data with a time resolution of 1 or 6 hours at four sites in the Kanto area, Japan, in summer 2007. All groups applied the Community Multiscale Air Quality model. The ensemble average of the four CTMs reproduced well the temporal variation of $O_3$ (r=0.65-0.85) and the daily maximum $O_3$ concentration within a factor of 1.3. By contrast, it underestimated $PM_{2.5}$ concentrations by a factor of 1.4-2, and did not reproduce the $PM_{2.5}$ temporal variation at two suburban sites (r=~0.2). The ensemble average improved the simulation of ${SO_4}^{2-}$, ${NO_3}^-$, and ${NH_4}^+$, whose production pathways are well known. In particular, the ensemble approach effectively simulated ${NO_3}^-$, despite the large variability among CTMs (up to a factor of 10). However, the ensemble average did not improve the simulation of organic aerosols (OAs), underestimating their concentrations by a factor of 5. The contribution of OAs to $PM_{2.5}$ (36-39%) was large, so improvement of the OA simulation model is essential to improve the $PM_{2.5}$ simulation.

• 한국대기환경학회지
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• 제20권4호
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• pp.539-553
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• 2004

Up to the present time, many methods to estimate emissions from a particular diesel engines have wholly depended on the quantity of diesel fuel consumed. Then, the recommended emission factors were normalized by fuel consumption, and further total activity was estimated by the total fuel consumed. One of main purposes in the study is newly to develop emission factors for the railroad diesel rolling stock (RDRS) and to estimate a total amount of major gaseous pollutants from the RDRS in Korea. Prior to develop a Korean mode emission factor. the emission factor from the USEPA was simply applied for comparative studies. When applying the USEPA emission factors, total exhaust emissions from the RDRS in Korea were estimated by 28,117tons of NOx, 2,832.3tons of CO, and 1,237.5tons of HC, etc in 2001. In this study, a emission factor for the RDRS, so called the KoRail mode (the Korean Railroad mode) has been developed on the basis of analyzing the driving pattern of the Gyeongbu-Line especially for the line-haul mode. Explicitly to make the site specific emission factors, many uncertainty problems concerning weighting factors for each power mode, limited emission test, incomplete data for RDRS, and other important input parameters were extensively examined. Total exhaust emissions by KoRail mode in Korea were estimated by 10,960tons of NOx, and 4,622tons of CO, and so on in the year of 2001. The emissions estimated by the USEPA mode were 2.6 times higher for NOx, and 1.6 times lower for CO than those by the KoRail mode. As a conclusion, based on the emission calculated from both the USEPA mode and the KoRail mode, the RDRS is considered as one of the significant mobile sources for major gaseous pollutants and thus management plans an(1 control strategies for the RDRS must be established to improve air quality near future in Korea.