• Journal of Korean Society of Water and Wastewater
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• v.27 no.5
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• pp.591-601
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• 2013

In modern society, we are living indoor at 80 - 90 % or more of the day, therefore most people are exposed to unconscious indoor air pollutants by various causes. When mother and infant, whose level of immunity are weak, are exposed to polluted indoor air, respiratory diseases and atopy can occur by the growth of bacteria. Therefore, appropriate indoor air quality management is important especially at nursery, elementary school and postpartum clinic etc. In this study, we compared the characteristics of the indoor air qualities of primary school facilities and infant facilities. In this study, seasonal effects were investigated. Also the effects of individual activity area were studied for indoor air quality. During summer season(May-August), the air qualities of each 16 elementary school and nursery school were investigated. During winter season(October-december), the air qualities of each 10 elementary school and nursery school were investigated. As a result, during winter season in 10 of 16 nursery school, $CO_2$ concentration exceeded regulation level of 1000 ppm. This resulted from the operation of heating system and poor ventilation. Also the air quality of all parameters during winter season were worse than during summer, maybe due to poor ventilation. Except HCHO, the concentrations of other parameters were higher in nursery school. This seems to result from relatively low individual activity area of nursery school than elementary school. From this research, more strong regulation for ventilation and installation of air purifier should be implemented.

• Journal of Korean Society of Forest Science
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• v.87 no.1
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• pp.74-81
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• 1998

The estimates of genetic diversity based on 7 polymorphic loci coding for 6 isozymes were compared between the tolerant and the sensitive trees in an air polluted Prunus sargentii stand located on Ulsan industrial area. Although we could not observe statistically significant differences in allele and genotype frequencies between the two groups except the gene locus Got-2, the unique alleles and genotypes were observed in the tolerant group. All the genetic parameters such as genetic multiplicity, genetic diversity, and heterozygosity revealed that a greater amount of genetic variations existed in the tolerant group.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.3
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• pp.297-310
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• 2007

Recent evidence has demonstrated that the pollutant recirculation can play an important role in leading to high ozone $(O_3)$ concentrations. In this study, the MM5-CAMx air quality modeling system was applied to simulate the pollutant recirculation and identify the transport of pollution during the high $O_3$ event (the maximum $O_3$ of 195 ppb) observed in the Greater Seoul Area (GSA) on $1{\sim}4$ June in 2004. The results showed a weak northeasterly synoptic wind during the night and early morning moved the air parcels containing the locally emitted urban pollution to the coast, which contributed to enhance $O_3$ formation in the southwest part of the GSA. As the sea breeze developed and started to penetrate inland in the late afternoon, the rapid build-up of $O_3$ concentration was found in the southwest coastal area due to the recirculation of the polluted air loaded with high level $O_3$. The simulated backward trajectories and observations at coastal sites confirmed the recirculation of pollutant with the late sea breeze is the dominant factor affecting the occurrence of high $O_3$ concentrations in the southwestern GSA.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.15 no.1
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• pp.97-104
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• 1986

This is to supply the basic data for saving energy and the appropriate way of waste disposal. The amount of waste disposed and its heat after burning is guessed to get conclusions. 1. The amount of disposable waste in 1990 in Seoul area is expected to be 2.2kg per man/day, coal ashes (YONTAN) 0.7kg, non-coal ashes 1.5kg. 2. The amount of waste combustible and heat after burning will be increased, and it is useful when the waste has Less than $70\%$ of water. 3. The method to collect waste should be specially organized, because most of the waste collected In Korea Is wet. 4. As the heat emitted from mass burning is $4\times10^{12}kcal/y$ in 1985, it is considered to be in senses of energy saving and the rationnal way of waste disposal. 5. Special concern is needed because the environment contaminated will be polluted in result of burning.

• The Korean Journal of Ecology
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• v.21 no.3
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• pp.313-320
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• 1998

Ameliorating effects of dolomite and sludge on the polluted soil sampled from Ulsan and yeocheon Industrial Complexes were investigated. Ameliorating effects were analysed by changes of soil properties and plant growth after treatment of dolomite and sludge. Soil properties were investigated by analysing organic matter, N, P, K, Ca and Mg contents and pH. Growth of sample plants was investigated by leaf area calculated from length and breadth of leaves and by biomass from diameter and height of sample plants. Quercus serrata and Celtis sinensis selected as tolerant plants in field survey were used as experimental plants. Treatment with dolomite showed ameliorating effects by increassing n, Ca, and Mg com\ntents, and pH of soil and by decreasing Al content. Treatment of sludge showed similar effects by increasing N, Ca, Mg and organic matter contents, and by decreasing A1 content. But treatment of sludge did not show any effect on pH. Both soil ameliorators showed accelerating effects on the growth of experimental plants in Ulsan soil. But those effects in Yeocheon soil were somewhat different. Treatment of sludge showed accelerating effects of the growth of both sample plants but dolomitic liming did not so. From those results, we confirmed availability of sludge, a kind of industrial waste, as one of ameliorators of the polluted soil. In addition, we recognized that soil properties had to be considered to select soil ameliorators suitable for restoration of degraded ecosystems.

• Journal of the Korean Society for Railway
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• v.5 no.1
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• pp.32-39
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• 2002

As most railways are gradually electrified with modernized electric cars, the demand for catenary wires and their facilities are also increased. Catenary Wires are exposed to the marine area with air-borne salt or severely polluted industrial area with much corrosive emission gases depending on the locations. Corrosion of catenaty wires can make their actual lifetime shorter than that originally designed. Thus, the messenger and ACSR wires, kinds of catenary wire system, were investigated with respect to corrosion, which include new and used ones collected at the field. Tensile strengths and elongations appeared to decrease when the wires were exposed to corrosive environments. The amount of decrease was more prominent as environmental conditions became more corrosive. They are also vibrated with some amplitude everytime pentographs touch contact line. The frequent cyclic load on the wire may result in a fatigue damage. Surface damage by corrosion can make fatigue crack initiate with ease. In the present study, the fatigue life of the used wire was measured 50 to 60% compared with that of new one in average.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.E2
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• pp.51-61
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• 2003

The material exposure tests have been carried out since 1993 to evaluate the relationship between air pollution and material corrosion with the cooperation of the researchers in Japan, China, and Korea. The test pieces such as bronze, copper, marble, and carbon steel have been exposed under both unsheltered and rain-sheltered outdoor condition separately at 18 sampling sites in East Asia. At the same time, the concentration of SO$_2$ and NO$_2$ has been measured simultaneously with passive sampler. The meteorological data were collected from the AWS (Auto-mated weather station) In each country and chemical compositions of wet deposition were also analyzed by the bulk sampling of rainfall every month. As the results, it was found that the corrosion rates of test pieces in the ambient air were appeared to be in the order of carbon steel > marble > bronze copper. The corrosion rates of test pieces in the unsheltered outdoor condition were 2.34 to 5.88 times larger than those in rain-sheltered condition. It was also found that the corrosion rate in the heavy polluted area in China was the highest, and the corrosion rates of the metal pieces were generally proportional to SO$_2$ concentration. Between two sites in Korea, the test pieces at Daegu site showed higher corrosion rates that would be due to the higher SO$_2$ concentration.

• Journal of Environmental Health Sciences
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• v.38 no.6
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• pp.472-481
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• 2012

Objectives: This study aims to investigate the AD (allergic diseases: asthma, allergic rhinitis and atopic dermatitis) prevalence among elementary schoolchildren in an industrial city, Ulsan, and identify major environmental risk factors associated with AD prevalence. Methods: Data on the physician-diagnosed prevalence over the past 12 months and potential risk factors of AD were collected through a questionnaire from a 2009-2010 survey of 4,067 schoolchildren living in different urban environments. The logistic regression analysis was performed to assess differences in AD prevalence among the areas and to determine which environmental factors impacted AD. Results: Our survey results showed that the AD prevalence rate ranged between 26.2% and 35.9%. Children living in polluted areas (near industrial and central urban areas) had about a 10% higher prevalence of AD than did those living in coastal or suburban residences. The Chi-Square test demonstrated that this local difference was statistically significant before and after adjustment of major confounders such as parental AD history and parental education. The results of the logistic regression analysis showed a statistically significant association between several environmental factors (ventilation in winter, odor conditions and exposure to traffic smoke, and outdoor $PM_{10}/O_3$ pollution) and the prevalence of AD found by multivariate model after adjusting confounders. Conclusion: These results suggest that local differences in AD prevalence are significantly associated with outdoor environmental factors. Although there are likely to be other risk factors for AD, living in a polluted area and exposure to high levels of air pollutants can contribute to an increased risk of childhood AD.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1309-1314
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• 2011

People spend approximately 80 ~ 90 % of their time in various kinds of indoor spaces. And, in metropolitan area, most people spend more than 1 hour in public transportation everyday. For this reason, people's interest in the indoor air quality is drastically increasing. Among various indoor air pollutants, $CO_2$ is one of the most severe environmental concerns. Ventilation is commonly used to keep low $CO_2$ concentration in the passenger cabin. However, ventilation may worse the indoor air quality problem in case of subway because the tunnel is seriously polluted by particulate matters. In this study, an alternative way to remove $CO_2$ was suggested. The adsorption of $CO_2$ by $CO_2$ adsorbent was studied. Zeolite modified with base was prepared, and $CO_2$ removal performance was tested in $4m^3$ and $24m^3$ environmental chambers. It was found that $CO_2$ adsorbent could effectively remove $CO_2$ in the chambers.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.4
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• pp.503-514
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• 2004

In Seoul metropolitan area, nocturnal variation of surface ozone concentrations observed at 27 monitoring sites from 1998 to 2002 showed that high ozone levels occurred frequently during the spring. Frequency distributions for nighttime ozone indicated that elevated concentrations in spring were influenced by advection of different air mass compared to other seasons. Surface wind analysis during the spring revealed that relatively strong southwesterly winds were associated with nocturnal ozone enhancement, which can be attributed to the regional transport of ozone. In order to identify the origin of nocturnal ozone enhancement in spring, 3-day backward trajectories were calculated by HYSPLIT 4 for the episode days and then classified. The results showed that NW, W, and SW flows, indicating influence of polluted air masses from the China continent, have 51% in a]1 the episode days, which suggest that the nocturnal ozone enhancement can occur under the effect of long-range transport of ozone-laden air mass on a regional scale. Case study of nocturnal ozone maxima associated with long-range transport was discussed in more detail in the light of meteorological conditions. Southwesterly synoptic flow along the outer edge of moving high-pressure system was found to be the important cause of nocturnal ozone maxima in Seoul. This flow could lead to be long-range transport of ozone that had effectively accumulated in the stagnating portion of the system located eastern coast of China. Low atmosphere soundings, backward trajectories, and elevated ozone and CO levels at the back-ground tiles gave evidence for regional effects on nocturnal ozone enhancement In Seoul.