• 한국산업보건학회지
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• 제18권2호
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• pp.133-140
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• 2008

In order to evaluate the possible environmental lead hazard in children's playground and to test the practicability of field portable x-ray fluorescence(FPXRF) for environmental lead measurement, authors investigated lead concentration of lead-based paint on the surface of children's playing equipments in the playground of 13 apartments using FPXRF at the site in city A, Choongnam province. 93 spots were determined surface lead concentrations 3 times each using a FPXRF. Out of 93 spots, 83 spots (92%) were revealed to have lead in paint and mean concentration was $1.12{\pm}1.76mg/cm^2$. The mean concentration of lead on the surface of playing equipments at the apartments near the main street was $1.20mg/cm^2$ and higher than those at the apartments far away from the main street($0.81mg/cm^2$)(p<0.05). The mean concentration of lead on the surface of playing equipments painted with yellow color was $3.23mg/cm^2$ and the highest among all colors, whereas equipment painted white color was non-detectable. PVC and etc materials for construction of playing equipment showed higher surface lead concentration than other materials. The result suggests that it is necessary to be taken caution of the lead exposure in the playground of apartment and it should be taken any kind of confirmative action to prevent unwanted lead exposure from surface lead source of playing equipment. Authors found that FPXRF was very reliable and useful for field measurement to detect lead on the painted surface.

• 한국지반환경공학회 논문집
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• 제17권7호
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• pp.27-33
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• 2016

This study expanded Terzaghi arching formula, which assumed a vertical surface as a sliding surface, to consider an arbitrarily inclined surface as a sliding surface and examined the effect of a sliding surface. This study firstly developed a formula to expand the existing Terzaghi arching formula to consider an inclined surface as well as a vertical surface as a sliding surface under the downward movement of a trap door. Using the expanded formula, the effect of excavation, ground, and surcharge conditions on a vertical stress was examined and the results were compared with them from Terzaghi arching formula. The comparison indicated that the induced vertical stress was highly affected by the angle of an inclined sliding surface and the degree of influence depended on the excavation, ground, and surcharge conditions. It is expected that the results from this study would provide a better understanding of various arching phenomenon in the future.

• 한국환경과학회지
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• 제24권8호
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• pp.969-980
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• 2015

In order to certificate the distribution and pollution of heavy metal of surface sediments in Nakdong River were collected and analyzed for grain size, water content, ignition loss and heavy metal content. Surface sediments mainly composed of sand(avg. 94.6%) and water content and ignition loss were 20.46%, 1.53% on average. Grain size were relatively fine and organic matter content were relatively high in the Hoichun and Sunakdonggang. Most of heavy metal content(Zn > Cr > Pb > Ni > Cu > Hg) in the Deokcheongang and Sunakdonggang were higher than the other streams. The Igeo were non polluted(less than 0) in all streams and the EF were relatively high in the small stream and PLI were non polluted(less than 1). In addition, organic matter, heavy metal content and pollution were highly correlation with grain size. Surface sediments in study area, heavy metal pollution of the Sunakdonggang were relatively high compared to the other stream but these results were not serious pollution that exceed the sediment pollution evaluation standard of river and lake in Korea and pollution levels adversely affected the majority of benthos were not.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2015년도 추계학술대회 논문집
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• pp.134-134
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• 2015

• 환경영향평가
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• 제19권4호
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• pp.397-407
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• 2010

The increase of the solar reradiation from urban areas relative to suburban due to urbanization heats up the air temperature in urban areas and this is called the urban heat island (UHI) effect. This UHI effect has a positive relationship with the degree of urbanization. Through the studies on UHI using the satellite imagery, the effect of the surface heat radiation was observed by verifying the relationship between the air temperature and the land cover types (surface materials such as urban, vegetation, etc.). In this study, however, the surface temperature distribution was studied in terms of land use types for Seoul. Using land use types, the surface temperature in urban areas such as residential, industrial, and commercial areas in Yeongdeungpo, highly packed with industrial and residential buildings, was maximum $6^{\circ}C$ higher than in the bare ground, which indicated that the surface temperature reflected the pattern of the human-consumed energy on the areas and showed that one of the important causes influencing the air temperature except the surface heat reradiation by the sun is the anthropogenic heat. Also, the effect due to the restoration of the Chunggae stream on UHI was investigated. The average surface temperature for the Chunggae stream was reduced about $0.4^{\circ}C$ after restoration. Considering that each satellite image pixel includes mixture of several materials such as concrete and asphalt, the average surface temperature might be much lower locally reducing UHI near the stream.

• 대기
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• 제16권4호
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• pp.371-378
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• 2006

The surface observation probability system (SOPS) of the Korea Multi-Purpose Satellite (KOMPSAT) has been developed based on the climatological distribution of cloud coverage and the expected passage of satellite orbit. While the optical camera loaded on KOMPSAT series has been operated with the purpose of observing earth's surface, it cannot see the surface when an obstacle (i.e., cloud) exists between them. In the present study, cloud information of International Satellite Cloud Climatology Project incorporates into high resolution grid of the KOMPSAT-3 orbit. The characteristics of the KOMPSAT SOPS are discussed.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권4호
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• pp.249-253
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• 2000

Data obtained from a cruise from 4~12 December, 1998 was analyzed to estimate the mixing effects of wind, surface cooling, and tide. A band denoting a mixing area with a temperature difference of less than 1$^{\circ}C$ between the sea surface and the bottom extended 40~60 km from the coast into the open sea, following 125$^{\circ}$ 30\` E in longitude. This band was divided into two areas; a well-mixed area close to the coast and a stratified region in the open sea. The mixing effect due to the wind was only 2%, yet the mixing effect due to the tides was about 68%. This indicates that surface cooling and tides were the major factors involved in the mixing mechanism on the west coast during the cooling season.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.590-593
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• 2004

Extraction of ocean surface current velocity offers important physical oceanographic parameters especially on understanding ocean environment. Although Remote Sensing techniques were highly developed, the investigation of ocean surface current using Synthetic Aperture Radar (SAR) is not an easy task. This paper presents the results of ocean surface current observation using Doppler Centroid of ERS-1 SAR data obtained off the coast of Korea peninsula. We employed the concept, in which Doppler frequency shift and the ocean surface current are closely related, to evaluate ocean surface current. Moving targets cause Doppler frequency shift of the back scattered radar waves of SAR, thus the line-of-sight velocity component of the scatters can be evaluated. The Doppler frequency shift can be measured by estimating the difference between Doppler Centroid of raw SAR data and reference Doppler Centroid. Theoretically, the Doppler Centroid is zero; however, squinted antenna which is affected by several physical factors causes Doppler Centroid to be nonzero. The reference Doppler Centroid can be obtained from measurements of sensor trajectory, attitude and Earth model. The estimated Doppler Centroid was compensated by considering the accurate attitude estimation of ERS-1 SAR. We could verify the correspondence between the estimated ocean surface current and observed in-situ data in the error bound.

• 한국환경과학회지
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• 제26권3호
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• pp.311-324
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• 2017

To certificate change in the geochemical characteristics of surface sediments in the main stream of the Nakdong River, surface sediments from 12 sampling sites during the first and second half year (total 24 sampling sites) were collected and analyzed for grain size, ignition loss, total organic carbon and heavy metal content. Surface sediments mainly composed of sand (coarse and medium sand) and fining changed from the first half to the second half of the year. Ignition loss, total organic carbon and heavy metals content increased in the second half of the year. Some heavy metals (Zn, Ni and Cu) were found to be at the lowest effect levels according to Ontario sediment quality guidelines. Additionally, most heavy metals were found to be at the non polluted level and level I according to USEPA sediment quality standards and National Institute of Environmental Research sediment pollution evaluation standard, respectively. The enrichment factor (< 1) and index of geoaccmulation (< 0) were non polluted in the study area. The correlation analysis results showed that ignition loss, total organic carbon and heavy metal content were highly correlated with grain size. Regarding changes in geochemical characteristics of surface sediments in the study area, grain size fine and organic matter and heavy metal content increased in the second half year. Nonetheless these results indicated pollution levels that did not adversely affect the benthos.

• Environmental Analysis Health and Toxicology
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• 제16권2호
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• pp.75-84
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• 2001

Differences in risk perception on major environmental issues between general public and environmental experts were investigated in this study. Questionnaire surveys were conducted to samples from general public and environmental experts during March and April, 2000. Total number of responses was 1,126 including 773 persons from general public and 353 experts. Risk perceptions on 26 environmental issues were related with the need to regulate each issue, controllability, experience, political views, interest in environmental problem, satisfaction of environment, severity of environmental pollution. There was statistically significant difference in risk perceptions between general public and experts. Overall, general public was likely to perceive risks associated with environmental problem, as well as social need to regulate these problems more than experts. The issues with high risk perception and need to regulate were 'automobile exhaust', 'industrial air pollution', ocean pollution by industrial waste and oil exhaust', 'air pollution by chemicals', 'surface water pollution by waste from household', 'industrial and hospital waste', 'surface water pollution by pesticide'and'sewage and food waste'. Consequently, it seems necessary to manage these issues, prior to others.