• Proceedings of the Safety Management and Science Conference
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• 2001.05a
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• pp.211-215
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• 2001

In the last year, the number of registered vehicles in Korea surpassed the 12 million mark, and increase in number continuously Nowdays, this tendency has raised some problems inevitably in the view of expansion of ELV(end of life vehicle) and earth environment pollution resulted from it. For the proper scope with this environment pollution, recycling of parts and materials, minimization of wastes are desirable. And application of disassembly technology is required for it necessarily. Therefore it is essential to study systematically about disassembly technology of ELV with high efficiency for improvement recycling ratio and diminution shredder dust amount also in Korea.

• Journal of the Korean Society of Food Culture
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• v.35 no.4
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• pp.363-370
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• 2020

This study analyzed the health characteristics and comorbidity of adult men aged 40 years by dividing them into a control group of those without any disease related to fine dust and a patient group with one or more diseases related to fine dust in areas with high levels of fine dust pollution using the sixth and seventh Korea National Health and Nutrition Examination Survey (2013-2017). Among the general characteristics, the mean age of the patient group was significantly older than that of the control group (p<0.001), and in terms of the health-related characteristics, the frequency of breakfast consumption in the patient group was higher than in the control group (p<0.043). The body measurements were similar in the patient and control groups. Regarding the prevalence of comorbidity, the patient group showed a higher prevalence of hypertension, dyslipidemia, stroke, myocardial infarction, heart failure, and diabetes than the control group, but the differences were not statistically significant. On the other hand, the prevalence of other cancers (except stomach cancer, liver cancer, colorectal cancer, breast cancer, and cervical cancer) in the patient group was higher than in the control group (p<0.05). In terms of the clinical characteristics, the glycated hemoglobin levels in the patient group were significantly higher than in the control group (p<0.048). Information on nutrition and health in areas with frequent occurrences of fine dust was obtained through the study results, which can be used as basic data for measures of health and diet management against diseases that will increase in relation to fine dust.

• Journal of environmental and Sanitary engineering
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• v.19 no.4 s.54
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• pp.9-18
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• 2004

In this study, the observation data for the yellow sandy dust phenomena from the year 1999 to 2003 at background sites in Korea were collected at Global Atmospheric Observatory at An-Myeon island and its temporal variation were analyzed. The chemical characteristics of the fine particles were also analyzed in order to evaluate sources of the yellow sandy dust particles. The results showed that the monthly average mass concentration of the fine particles was the highest in springtime and the lowest in summertime in general. The magnitude of its variation was also the highest in March in which the occurrence of yellow sandy dust was the most frequent and thus the number of samples was the largest, while the lowest in June through September. The yearly variation of ion components contributions to the total mass concentration of the fine particles was slowly decreasing, showing that $63\%$ in 1999, $59\%$ in 2000 and $56\%$ in 2003. The most prevalent ion components in the fine particles were found to be $NO_3$ and $SO_4^{2-}$, which are known to be source materials of acidic precipitation, and $NH_4^+$, a neutralizing material of the acid precipitation. Relative proportion of metal components in the fine particles was calculated as $14\%$ in average, and their concentrations are in an order of Fe > Al > Na > Ca > Zn > Pb > Cu > Mn > Ni > Cd > Cr > Co > U. The results indicated that main sources of the metals was soil-originated Fe, Al, Ca, and Mg, and the contribution of anthropogenic air Pollution-originated Zn, Pb, Cu, Mn were also high and keep slightly increasing. Statistical analysis showed that the chemical components could be divided into soil-originated group of Mg, Al, Ca, Fe, and Mn and air pollution-originated group of $NO_3$, Zn, Pb, and they are occupying more than $60\%$of all the components in the dusty sand. The results explain that An-Myeon island is more influenced by soil-originated source than ocean-originated one and also the influencing strength of anthropogenic poilution-originated source is less than $50\%$ of that of soil-originated sources. Compared to non-yellow sandy period, the yellow sandy dust period showed that the amounts of soil-originated $Mg^{2+}$ and $Ca^{2+}$ and ocean-originated $Na^+$ and $Cl^-$ were increased to more than double and the metals of Mg, Al, Ca, Fe were also highly increased, while micro metal components such as Pb, Cd, Zn, which have a tendency of concentrating in air, were either decreased or maintained at nearly constant level. In the period of yellow sandy dust, a strong positive correlation was observed between water soluble ions and between metals in terms of its concentration, respectively. Factor analysis showed that the first group being comprised of about $43\%$ of the total inorganic components was affected by soil and they are ions of $Na^+,\;Mg^{2+}\;and\;Ca^{2+}$ and metals of Na, Fe, Mn and Ni. The result also showed that the metals of Mg and Cr were classified as second group and they were also highly affected by soil sources.

• Journal of the Korean Ceramic Society
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• v.53 no.4
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• pp.444-449
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• 2016

Industrial by-products generated by integrated iron and steel manufacture cause environmental pollution. The by-products contain not only iron element but also harmful substances. Therefore, in view of to waste recycling and environmental preservation, production of sponge iron using the by-product is considered an effective recycling method. In this study, reduction efficiency of pellets from blast furnace dust was measured. Metallization was found to be increased, as $C/Fe_{total}$ ratio and reaction time were increased. The pellets were formed into a globular shape, and calcined for 60 minutes at $1100^{\circ}C$ in an electric furnace. Phase changes were analyzed using an X-ray diffractometer. Microstructures of the pellets were observed by a scanning electron microscope.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.501-502
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• 2003

매년 우리나라를 찾아오는 황사는 주로 중국 북부의 황토 지대에서 바람에 의하여 하늘 높이 불어 올라간 무수의 모래 먼지가 서서히 강하하는 현상 또는 강하하는 모래 먼지를 말한다(최재천 등, 2001). 황사는 동아시아 지역에서 태평양을 가로질러 하와이까지 수송되면서 국제적으로 중요한 이슈가 되고 있으며, 아프리카 사하라 사막에서 발생한 사하라 먼지(Sahara dust)가 대서양을 가로질러 플로리다반도에서 관측됨으로서 세계적인 문제로 대두되고 있다. 최근에는 황사의 농도뿐만 아니라, 황사 중에 포함된 중금속의 농도에 관한 관심이 고조되고 있다(전병일, 2003).(중략)

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.65-66
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• 2021

Due to the inexperience of stone work and field workmanship, and the preference of simple construction, various problems such as unauthorized cutting of the touch and epoxy bonding are occurring. Therefore, the existing T-type hole construction method was developed to fundamentally control these attempts. As a result of comparison with the control panel method, vibration and noise were reduced by 2dB and 10dB, indicating an excellent effect. Particularly, dust was about 1/102~1/61 in individual values, and the average value was 1/80 (12.5%). The effect of preventing damage and environmental pollution is expected to be great.

• Economic and Environmental Geology
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• v.45 no.3
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• pp.217-235
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• 2012

We evaluated the geochemical characteristics and their potential pollution of Asian Dusts in Daejeon, Korea during spring 2007. Compared with the chemical compositions of soils in source area of Asian Dust, those of aerosols in Daejeon were enriched with trace elements (ten to hundred fold), inferring that pollutants from China have affected on local environment in adjoining country such as Korea. Chemical analysis of aerosols during Asian dust showed that fine particles ($PM_{2.5}$) contained high contents of trace elements such as Cr, Cu, Pb, Zn, V, S, As, Cd, Co, Ni, Mo, Sb, Cs, Rb, Th, Sc and Y. In the case of TSP (Total Suspended Particle), Zr, Sr, Ba, Li, Th and U were contained much more than other trace elements. The contents of some elements (i.e. Li, Cs, Co, U, Cr, Ni, Rb, V, Th, Y, Sr and Sc) in aerosols collected in Asian Dust period, which are not likely enriched by air pollutants, were higher (2 - 4.2 fold) than those in Non Asian Dust period, indicating that these elements could be used as indicator elements for determining the occurrence of Asian Dust phenomena (especially, Sr, V, Cr & Li). In the case of Asian Dust coming through the big cities and/or industrial areas of China, the domestic aerosols had higher contents of trace elements (such as S, Cd, Zn, Pb, Cu, Mo and As) than those from Northeastern China via North Korea, indicating that the transportation courses of air mass are very important to determine the pollution degrees. Using the enrichment factors of trace elements in aerosols during Asian Dust and Non Asian Dust, we identified that some elements (i.e. S, Zn, Cu, Pb, As, Mo and Cd) were most problematic in terms of environmental hazard aspects, and these elements could affect adverse effects on human health as well as ecosystem and surface environment (soil and water) through long-lived precipitation.

• Atmosphere
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• v.27 no.1
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• pp.41-54
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• 2017

Organic carbon (OC) and elemental carbon (EC) in $PM_{2.5}$ were measured using Sunset OC/EC Field Analyzer at Seoul Hwangsa Monitoring Center from March to April, 2016. The mean concentrations of OC and EC during the entire period were $4.4{\pm}2.0{\mu}gC\;m^{-3}$ and $1.4{\pm}0.6{\mu}gC\;m^{-3}$, respectively. OC/EC ratio was $3.4{\pm}1.0$. The average concentrations of $PM_{10}$ and $PM_{2.5}$ were $57.4{\pm}25.9$ and $39.7{\pm}19.8{\mu}g\;m^{-3}$, respectively, which were detected by an optical particle counter. The OC and EC peaks were observed in the morning, which were impacted by vehicle emission, however, their diurnal variations were not noticeable. This is determined to be contributed by the long-range transported OC or secondary formation via photochemical reaction by volatile organic compounds at afternoon. A conditional probability function (CPF) model was used to identify the local source of pollution. High concentrations of $PM_{10}$ and $PM_{2.5}$ were observed from the westerly wind, regardless of wind speed. When wind velocity was high, a mixing plume of dust and pollution during long-range transport from China in spring was observed. In contrast, pollution in low wind velocity was from local source, regardless of direction. To know the effect of long-range transport on pollution, a concentration weighted trajectory (CWT) model was analyzed based on a potential source contribution function (PSCF) model in which 75 percentiles high concentration was picked out for CWT analysis. $PM_{10}$, $PM_{2.5}$, OC, and EC were dominantly contributed from China in spring, and EC results were similar in both PSCF and CWT. In conclusion, Seoul air quality in spring was mainly affected by a mixture of local pollution and anthropogenic pollutants originated in China than the Asian dust.

• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.239-241
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• 2003

The development of industry environment honored dust matter is diversify industry part eliminate the source of pollution besides usually life in and around pollution by livestock farming pollution matter and pollution by used agricultural medicines particular eutrophic of in and around a reservoir present of occurrence accelerate. The paper is a study of dissolved characteristics by ozone contactor type and ozone generated quantity.

• IEMEK Journal of Embedded Systems and Applications
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• v.9 no.4
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• pp.229-235
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• 2014

This paper presents an environmental navigation system which provides a guidance to the users of smart bicycle for a pollution-free route during their travel. The smart bicycle operates as a sensor node being composed of a distributed wireless sensor network over the whole urban area. Several environmental sensors measuring the amount of dust, CO, $CO_2$, $NO_2$ in the air are built into the smart bicycle to estimate the level of air pollution in the located area. Each smart bicycle sends/receives the measured sensor data and the city pollution map to/from the centralized server, which leads the bike-riders to a healthy route by providing the environmental navigation information. The proposed idea and its implementation give a useful insight on various application services with the distributed smart bicycles.