• Journal of Environmental Science International
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• v.11 no.8
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• pp.801-810
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• 2002

The current paper describes the indoor/outdoor air quality in school environments through analyses of the heavy metal concentrations using Inductive Coupled Plasma(ICP). School environments in a heavy traffic area, two industrial areas, quasi-industrial area, and residential area were evaluated. The results were as follows: (1) The locations with the highest indoor and outdoor concentrations of heavy metals were the industrial areas followed by the heavy traffic area, residential area, and quasi-industrial area in a descending order of magnitude. Plus, the indoor heavy metal concentrations were higher then the outdoor ones. (2) The main heavy metal components were Zn, Al and Ca. Higher concentration levels were found indoors than outdoors. The heavy metal concentrations were also higher in the classrooms than in the corridor or outdoors. (3) The total heavy metal concentrations in the studied areas were highly dependent on the weather elements. including the relative humidity, mixing ratio, and wet-bulb depression. Accordingly, special ventilation systems are recommended to reduce air pollution in school environments.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.1032-1037
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• 2006

This thesis studied effects of the excavation around railroads on the deformation of the lateral ground and neighboring railroads. The conclusions of the study are as follows. 1. When the depth of excavationis 10m, the influential area should be 35m for soft clay, 20m for normal clay, 15m for hard clay, 15m for loose sand, 12m for slightly dense sand, and 8m for dense sand. 2. When the influential area is 10m, the allowable excavation depth should be 2.5m for soft clay, 4.8m for normal clay, 7.5m for hard clay, 7.2m for loose sand, 8.8m for slightly dense sand, and 10m for dense sand. 3. When the influential area is 20m, the allowable excavation depth should be 4.5m for soft clay, and up to 10m for the other five kinds of soil. 4. When the influential area is 30m, the allowable excavation depth should be 7.5m for soft clay, and up to 10m for the other five kinds of soil. 5. When the influential area is 35m, the allowable excavation depth should be up to 10m for all kinds of soil.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.291-291
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• 2010

Organic solar cells have attracted much interest due to the potential advantage of the lightness, simple solution processing and flexibility. Until recently, the focus of organic solar cells research has been on optimization of material processing to improve the power conversion efficiency. However, area scaling is an important position for alternative to the market dominating solar cells. Spray deposition technologies have advantage of less material wastage and possibility of large scale photoactive area coating when compared with spin coating process. We investigated the performance of organic solar cells as a function of active area using two types of deposition process. The commonly used process is spin coating which can be fabricated organic materials deposition for devices. Spray deposition process compare with spin coating for large-area organic solar cells. The spray deposition organic layer shows excellent performance up to the active area of $4\;cm^2$ with the PCE of ~3.0 % under AM.1.5 simulated illumination with an intensity of $100mW/cm^2$. This indicates that the spray deposition process can be used as a mass production process for evaluating large-area organic solar cells.

• Tunnel and Underground Space
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• v.30 no.6
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• pp.551-558
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• 2020

This note presents the calculation of nominal area for rock core specimen under direct shear testing condition. The initial nominal area was assumed as ellipsoid, and the equations for calculating the nominal area are derived. The normalized shear displacement and normalized nominal area have an identical relationship regardless of the ellipsoid shape. New testing constants and the generalized method were suggested to calculate the decrease of the nominal area. The method was applied to calculate the direct shear testing data and the changes of result were discussed.

• Journal of Korean Association for Spatial Structures
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• v.23 no.1
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• pp.35-43
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• 2023

Microclimate analysis was conducted through actual measurement according to land use status in urban, and CFD analysis was conducted to analyze and predict the microclimate characteristics of urban, and compared and analyzed with the actual measurement results. It was measured in high-rise areas and parks, and the temperature of the park area was 0.4 to 0.6℃ lower, and the relative humidity was 1.0 to 3.0% higher. The correlation coefficient was obtained by comparing the results of the computational fluid analysis with the results of the computational fluid analysis at the actual location located within the CFD analysis area for validation. The seasonal correlation coefficients are all higher than 0.8, so it is judged that they can be applied to microclimate analysis in urban area. The computational fluid analysis was divided into three areas (low-rise, low and high-rise, and high-rise) centered on the A2 point. On average, the low-rise area was 0.1 to 0.4% higher than the high-rise area. In the low and high-rise area and high-rise area, the pith of buildings are wide, so the airflow is smooth, so it is judged that the temperature is relatively low.

• Korean Journal of Veterinary Service
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• v.25 no.1
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• pp.1-7
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• 2002

Recently, the rabies cases have been reported in Paju- and Yangju-gun, Gyeonggj province near Seoul metropolitan area. The Pukhansan national park, nearly located from the cities, is suspected to be a high risk area for incidence and spread of the rabies to metropolitan area. This study was conducted to investigate the prevalence rate for rabies antibody of dogs near the Pukhansan national park and in some other districts in Seoul metropolitan city. From march to october 2001, a total of 306 serum samples were taken from dogs for breeding(189) md pet dogs(117) in 4 districts near the Pukhansan national park and other districts of Seoul. Rabies virus antibodies in sera were detected by neutralizing peroxidase - linked as say (NPLA). Of the 306 sera of dogs tested, 74 (24.2%) were positive to rabies virus antibody. The prevalence rates of rabies antibody in Pukhansan national park area and in the other districts of Seoul city were 23.7% and 25.3%, respectively There was no significant difference in the prevalence rate between these two districts. The prevalence rates of rabies antibody in pet dogs and dogs for breeding were 40.2% and 14.3% respectively. The prevalence rates of rabies antibodies in less than 1 year, 1∼<2 years, 2∼<3 years, and over 3 years old dogs were 14.5%, 22.4%, 32.6%, and 27.1%, respectively, and overall 24.2% in the dog population. In addition, we found that dogs less than 1 year old had lower antibody prevalence than those over 1 year old. It was concluded that enhancement of vaccination is important in the prevention of the rabies, and that rabies vaccines should not be less supplied than the population of the dog.

• Journal of Forest and Environmental Science
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• v.38 no.2
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• pp.128-132
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• 2022

Wild boars (Sus scrofa) not only cause crop damage and human casualties, but also facilitate the spread of many infectious diseases in domestic animals and humans. To determine the efficiency of a fencing system in blocking the movement of wild boars, long-term monitoring was performed in a fenced area in Bukhansan National Park using camera traps. Upon monitoring for a period of 46 months, there was a 72.6% reduction in the number of wild boar appearances in the fence-enclosed area, compared to that in the unenclosed area. For 20 months after the fence installation, the blocking effect of the fence was effective enough to reduce the appearance of wild boars by 92.6% in the fence-enclosed area, compared to that in the unenclosed area. The blocking effect of the fence remained effective for 20 months after its installation, after which its effectiveness decreased. Maintaining a fence for a long time is likely to lead to habitat fragmentation. It can also block the movement of other wild animals, including the endangered species - the long-tailed goral. This study suggests a 20-month retention period for the fences installed to inhibit the movement of wild boars in wide forests such as Gangwon-do in South Korea. To identify how long the blocking effect of the fences lasts, further studies are needed focusing on the length and height of the fence, and the conditions of the ground surface.

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.3
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• pp.27-34
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• 2011

The definition of a rural theme park was presented and it's development directions were set up as grasping the problems of existing rural theme park. The creation method of a rural theme park was presented through the case study of a design planning. A rural theme park should be designed with consideration to regional characteristics based on the rural amenity. The characteristics of rural theme parks set by theme, unity, integrity, originality, and eco-friendly. And the visit reasons of rural theme park are rural experience, lodging, relaxation or recreation, comfort or easy, and food purchase. A case study area is around Geopo-Ri and Gueum-Ri Okcheon-Gun Chungcheongbuk-Do. The master plan of this area was prepared.

• Korean Journal of Environment and Ecology
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• v.13 no.4
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• pp.375-381
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• 2000

1999년 7월 24일부터 7월 25일까지 지리산국립공원 중 동부지역 일대에서 양서류 및 파충류상을 조사한 결과 양서류는 총 2목 5과 8종 파충류는 1목 3과 6종이 관찰 및 탐문으로 조사되었다 이번 조사에서 두꺼비 1종의 고유종이 관찰되었으며 외래종과 환경부 지정 보호야생동물 및 멸종위기종은 관찰되지 않았다.

• Proceedings of the Korean Society of Crop Science Conference
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• 2018.10a
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• pp.34-34
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• 2018