• Asian Journal of Atmospheric Environment
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• v.10 no.2
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• pp.67-79
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• 2016

The forecasting of air pollution is an important and popular topic in environmental engineering. Due to health impacts caused by unacceptable particulate matter (PM) levels, it has become one of the greatest concerns in metropolitan cities like Karaj City in Iran. In this study, the concentration of $PM_{2.5}$ was predicted by applying a multilayer percepteron (MLP) neural network, a radial basis function (RBF) neural network and a Markov chain model. Two months of hourly data including temperature, NO, $NO_2$, $NO_x$, CO, $SO_2$ and $PM_{10}$ were used as inputs to the artificial neural networks. From 1,488 data, 1,300 of data was used to train the models and the rest of the data were applied to test the models. The results of using artificial neural networks indicated that the models performed well in predicting $PM_{2.5}$ concentrations. The application of a Markov chain described the probable occurrences of unhealthy hours. The MLP neural network with two hidden layers including 19 neurons in the first layer and 16 neurons in the second layer provided the best results. The coefficient of determination ($R^2$), Index of Agreement (IA) and Efficiency (E) between the observed and the predicted data using an MLP neural network were 0.92, 0.93 and 0.981, respectively. In the MLP neural network, the MBE was 0.0546 which indicates the adequacy of the model. In the RBF neural network, increasing the number of neurons to 1,488 caused the RMSE to decline from 7.88 to 0.00 and caused $R^2$ to reach 0.93. In the Markov chain model the absolute error was 0.014 which indicated an acceptable accuracy and precision. We concluded the probability of occurrence state duration and transition of $PM_{2.5}$ pollution is predictable using a Markov chain method.

• Journal of Environmental Health Sciences
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• v.41 no.4
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• pp.259-267
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• 2015

Objectives: This study evaluated the regional and seasonal concentrations of ambient hazardous heavy metals in an industrial complex area in Daegu City. Methods: A total of 64 SPM (Suspended Particulate Matter) samples were collected in non-industrial and industrial areas during 2014 and were analyzed for hazardous heavy metals elements (As, Cd, Mn, Ni, Pb) with ICP after acid extraction. Results: SPM and hazardous heavy metals concentrations showed regional (industrial complex area>non-industrial complex area) and seasonal (spring, winter>fall, summer) variations. All of the hazardous heavy metals were influenced by anthropogenic sources. The pollution index of hazardous heavy metals was very low, showing roughly one-quarter of the level of the air quality guidelines of WHO. The correlation analysis among SPM and hazardous heavy metals indicated that components of non-industrial complex areas were more related to each other than those of industrial complex areas, and the correlation in the winter was higher than in other seasons. Conclusion: It is necessary to control air pollution sources and establish related policy because hazardous heavy metals from industrial areas can influence residential areas.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.5
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• pp.449-460
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• 2014

Since the emergence of domestically produced automobiles in 1964, the number of automobiles in circulation in South Korea has increased constantly. With this rapidly increasing number of automobiles, automobile-induced environmental pollution has become an issue of great concern, especially with regard to air pollution. Of the carbon composites contained in automobile exhaust gas, PAHs are known to be carcinogenic and highly deleterious to humans and thus need to be urgently mitigated. To address this issue of PAHs, this study was conducted to estimate qualitative of particulate PAHs contained in carbon composites in automobile exhaust gas, by capturing all particulate matter discharged from the latter. To allow for differentiated analyses, the automobiles investigated were divided into 4 groups: gasoline vehicle, motocycle, diesel vehicle, and LPG vehicle. Samples were analyzed using two methods. First, in-depth analysis was performed on organic carbon (OC) and elemental carbon (EC) composites with analysis parameters, using the Thermal Optical Transmittance Method (NIOSH 5040). Second, for the examination of particulate PAHs, GC/MSD was used to analyze the 16 PAH species specified by the Environmental Protection Agency (EPA). The analyses yielded the findings that diesel vehicles had the highest mass concentration ($2,007{\mu}g/m^3$), followed by motocycle ($1,066{\mu}g/m^3$), LPG vehicle ($392{\mu}g/m^3$), and gasoline vehicles ($270{\mu}g/m^3$). The highest carbon concentrations in total particulate matter by vehicle weight were produced from LPG vehicle (79.8%), followed by gasoline vehicle (77.4%), motocycle (69.8%), and diesel vehicle (59.1%).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3740-3747
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• 2009

To protect the citizens' health of Gyeongju and to secure basic data for the assessment of health and environmental risk, distribution characteristics of meteorological elements were investigated and numerical simulation of wind field using RAMS model was carried out. In addition, measurement and analysis of air pollutants, forecasting the behavior air pollutants using ISC-AEROMOD view, and health and environmental risk-influenced zones were defined through managing air polluting materials to prevent health damage and property damage. According to the survey results of air pollution in Gyeongju and surroundings, average annual concentration of air pollutants in Gyeongju was slightly lower than that in Pohang and Ulsan areas, but concentration of particulate matters and nitrogen dioxide at Gyeongju Station Square and Yonggang Crossing were sometimes higher than that in Pohang and Ulsan areas. Results of the modeling of moving and diffusion of air pollutants that affect citizens' health showed that parts of the 1st through 4th industrial complexes together with POSCO were included in particulate matters and sulfur dioxide influenced areas in Pohang Steel Complex area, and that Haedo-dong, Sangdae-dong, Jecheol-dong and Jangheung-dong in Pohangnam-gu represented locally worsened air quality due to a quantity of air pollutant emission from dense steel industries and large scale industrial facilities.

• Journal of Korean Society for Atmospheric Environment
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• v.3 no.1
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• pp.65-73
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• 1987

Indoor air pollution problems, in fact, have been neglected due to the unawareness of its seriousness and the lack of accumulated data. Recently, some movement of research and regulations, however, have been made for several indoor air pollutants. In this study, one of the carcinogenic polynuclear aromatic hyrocarbon, Benzo(a) pyrene in indoor airborne particulate, was measured and analyzed to estimate emission strength of BaP from an unvented kerosene heater and to know its level in indoor environment with use of a kerosene heater and a wood-burning fireplace. By the measurement of BaP level in a dark room with air exchange rate of app. 3.0, BaP emission strength of a kerosene heater (11,000Btu/hr) was estimated to be 326.6ng/hr (or 29.7 ng/$10^3$ Btu). With 4-hr operation a day of the kerosene heater in an apartment, the BaP level became 2.97ng/m$^3$ from 0.27ng/m$^3$ of background level. The operation of a wood-burning fireplace app. 2hr a day, on the other hand, increased the BaP level from 0.16ng/m$^3$ of background to 3.53ng/m$^3$. So proper ventilation must be considered seriously when unvented heating facilities are used in indoor environment.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.47 no.3
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• pp.185-191
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• 2021

Environmental pollution is defined as contamination of the earth's environment with materials which interfere with human health, quality of life, or the natural functioning of the ecosystem. Whenever a prolonged and repetitive exposure to environmental stressors exceeds the skin's normal defensive potential, there is a disturbance in the skin barrier function leading to the development of various skin diseases. Major air pollutants which affect the skin are polycyclic aromatic hydrocarbons, volatile organic compounds, nitrogen oxides, particulate matter, cigarette smoke, heavy metals and arsenic. Dermal uptake depends on the deposition of air pollutants on the skin surface, the composition of epidermal lipids, and the diffusion through the epidermis to the blood vessels.

• Analytical Science and Technology
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• v.23 no.1
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• pp.15-23
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• 2010

To investigate pollution level of PFOA and PFOS in ambient air, Cheongju city, gaseous and particulate samples were collected at industrial, residential/commercial, and rural region, respectively. Samples were collected in winter, spring, and summer season in order to examine seasonal variation of PFOA and PFOS. The concentration range of PFOA and PFOS was presented as N.D.~8.02 pg/$m^3$ with an average of 2.33 pg/$m^3$, 1.68~6.94 pg/$m^3$ with an average of 3.12 pg/$m^3$. These levels were lower than or similar to those of other countries.

• Kosin Medical Journal
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• v.33 no.2
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• pp.171-180
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• 2018

Objectives: We investigated whether asthma attacks in asthmatic children were caused by short-term exposure to particulate $matter(PM)_{2.5}$. Methods: Subjects were 411 patients who received inhalation therapy in National Fukuoka Hospital, from March to May 2013. All subjects were outpatients. We surveyed the air quality measurement results in the stations closest to the address of the patients. Data were used from the City of Fukuoka website data on air pollution. We carried out a case-crossover study and compared $PM_{2.5}$ concentration between 7 days after asthma attack occurred and the day asthma attack occurred and 1, 2 and 3 days before asthma attack occurred. Results: Highest hourly concentration of the day (OR 1.013, 95%CI 1.000-1.025) showed a significant association with 1 day before $PM_{2.5}$ concentration statistically. And 0-1 year-old infants were more vulnerable to the highest concentration of 1 day before $PM_{2.5}$ concentration(P < 0.05). Average concentration of $NO_2$ and $O_3$ and asthma attack also showed a significant association. Conclusions: Maximal daily $PM_{2.5}$ concentrations within 24 hours prior to the attack affect asthma exacerbation. 0-1 year-old infants are particularly vulnerable to $PM_{2.5}$ concentration. Asthma exacerbation is aggravated by $NO_2$ and $O_3$ concentration on the day of the asthma attack.

• Clean Technology
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• v.19 no.2
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• pp.95-104
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• 2013

Onsan Industrial Complex located in a nearby the Ulsan Petrochemical Complex and in the east of the coast. For this reason, air pollution substances emitted by Onsan Industrial Complex especially tend to have an effect on meteorological factors such as sea breeze. In this study, we assessed the frequency of sea breeze and mist using the meteorological data, and analyzed potential temperature and upper wind condition for assessment of atmospheric pollution concentration influenced by meteorological phenomena in a nearby the Onsan industrial complex. From an analysis results, when mist and sea breeze happened, each higher concentration phenomenon of $PM_{10}$ and $SO_2$ appeared each 57.2%, 71.8% and 46.6%, 57.7% respectively. Hence, we confirmed that meteorological phenomena such as mist and sea breeze had an effect on high concentration of air pollution substances in the research area. Analytical result of meteorological data in upper layer using potential temperature and wind condition, we confirmed that advection of air pollution substances emitted in Ulsan Petrochemical Complex by sea breeze have an effect on high concentration in Onsan Industrial Complex and nearby the residential area. In particular;concentration in Onsan Industrial Complex were higher than the average concentration by a factor of more than over 1.5 times when sea breeze by stable condition in atmospheric layer appeared.

• Journal of Preventive Medicine and Public Health
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• v.49 no.5
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• pp.329-341
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• 2016

Objectives: The goal of this study was to investigate the short-term effect of ambient air pollution on emergency department (ED) visits in Seoul for asthma according to patients' prior history of allergic diseases. Methods: Data on ED visits from 2005 to 2009 were obtained from the Health Insurance Review and Assessment Service. To evaluate the risk of ED visits for asthma related to ambient air pollutants (carbon monoxide [CO], nitrogen dioxide [$NO_2$], ozone [$O_3$], sulfur dioxide [$SO_2$], and particulate matter with an aerodynamic diameter <$10{\mu}m$ [$PM_{10}$]), a generalized additive model with a Poisson distribution was used; a single-lag model and a cumulative-effect model (average concentration over the previous 1-7 days) were also explored. The percent increase and 95% confidence interval (CI) were calculated for each interquartile range (IQR) increment in the concentration of each air pollutant. Subgroup analyses were done by age, gender, the presence of allergic disease, and season. Results: A total of 33 751 asthma attack cases were observed during the study period. The strongest association was a 9.6% increase (95% CI, 6.9% to 12.3%) in the risk of ED visits for asthma per IQR increase in $O_3$ concentration. IQR changes in $NO_2$ and $PM_{10}$ concentrations were also significantly associated with ED visits in the cumulative lag 7 model. Among patients with a prior history of allergic rhinitis or atopic dermatitis, the risk of ED visits for asthma per IQR increase in $PM_{10}$ concentration was higher (3.9%; 95% CI, 1.2% to 6.7%) than in patients with no such history. Conclusions: Ambient air pollutants were positively associated with ED visits for asthma, especially among subjects with a prior history of allergic rhinitis or atopic dermatitis.