• Korean Journal of Environmental Biology
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• v.33 no.4
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• pp.425-432
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• 2015

Pollution in the fresh water system in urban area has the adverse effect on the amphibians population. Restoration activity of amphibian in the urban stream has been growing in Korea as well as western country. For successful restoration water quality of urban stream should be sufficient for survival and normal development of amphibian. To monitor the biological safety of surface water in the Tancheon basin, the capital area of Korea, a 6-day exposure Bombina orientalis embryo developmental toxicity assay was examined. The toxicity of surface water of Tancheon mainstream were lower than those of tributaries of Tancheon. The survival rate of embryos negatively correlated with total dissolved solid, turbidity and electrical conductivity whereas the developmental abnormality and growth retardation of embryos was positively correlated with total dissolved solid, turbidity and electrical conductivity. An amphibian developmental toxicity assay would be helpful for the selection of point for construction of habitat and reintroduction of amphibian in interrupted urban stream.

• Korean Journal of Environment and Ecology
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• v.26 no.5
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• pp.801-811
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• 2012

The purpose of this study is to find out how land cover and planting of an urban park influence temperature. Field research on the land cover and planting status was conducted for Bundang Central Park in Sungnam-si. 30 study plots in the site were selected to closely analyze land cover type and planting structure. The temperature was measured 10 times for each plot. Land coverage type, planting type, planting layer structure and green space area (the ratio of green coverage, GVZ) were chosen as factors impacting temperature and statistics were analyzed for the actual temperature measured. Analysis on how the land coverage type influences temperature showed that planting site had a low temperature and that grassland and paved land had a high temperature. When it comes to planting type, the temperature at the land planted with conifers and broad-leaved trees was low, while the temperature at grassland and paved land was high. With regard to planting layer structure, canopy and canopy-underplanting type showed low temperature, while grassland and paved land showed high temperature. An analysis on the relation between green space area and temperature found out that both ratio of green coverage and GVZ had a high level of negative correlation with the temperature measured. According to regression model of green space area and the temperature measured, for every 1% increase in the ratio of green coverage, temperature is expected to lower by $0.002^{\circ}C$. Also, for every $1m^3/m^2$ increase in GVZ, temperature is expected to go down by $0.122^{\circ}C$.

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.262-268
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• 2019

BACKGROUND: To investigate mineralization characteristics of organic resources in the soil, five materials (rice straw, cow manure sawdust compost, microorganism compost, mixed oil-cake, and amino acid fertilizer) were treated according to the nitrogen content, and an indoor incubation experiment was conducted for 128 days. The results of this analysis were applied to determine the nitrogen mineralization pattern of these organic resources. METHODS AND RESULTS: During the constant temperature incubation period, the nitrogen net mineralization rate of the organic resources was the highest in the amino acid fertilizer with the highest nitrogen content, and the lowest in the rice straw with the lowest nitrogen content. A positive correlation (0.96) was observed between the potential nitrogen mineralization rate and total nitrogen content. The mineralization rate constant, k, was negatively correlated with the organic matter (-0.96) and carbon content (-0.97). The nitrogen mineralization rate during the first cropping season, as estimated by the model, was 6.6%, 11.6%, 30.9%, 70.7%, and 81.0% for the rice straw, the cow manure sawdust compost, the microorganism compost, the mixed oil-cake, and the amino acid fertilizer, respectively. CONCLUSION: The nitrogen mineralization rate varies depending on the type of organic resources or the nitrogen content; thus, it can be used as an index for determining the nitrogen supply characteristics of the organic resource. Organic resources such as compost with low nitrogen content or those undergoing fermentation contain organic nitrogen. Organic nitrogen is stabilized during the composting process. Therefore, as the nitrogen mineralization rate of these resources is lower than that of non-fermented organic resources, it is desirable to use the fermented organic materials only to improve soil physical properties rather than to supply nutrients for the required amount of fertilizer.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.4
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• pp.76-91
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• 2016

The purpose of this study is to analyze the effects of spatial characteristics, such as land cover and topography, on heat wave days from the city of Milyang, which has recently drawn attention for its heat wave problems. The number of heat wave days was calculated utilizing RCP-based South Korea climate data from 2000 to 2010. Land cover types were reclassified into urban area, agricultural area, forest area, water, and grassland using 2000, 2005, and 2010 land cover data constructed by the Ministry of Environment. Topographical features were analyzed by topographic position index (TPI) using a digital elevation model (DEM) with 30 m spatial resolution. The results show that the number of heat wave days was 31.4 days in 2000, which was the highest, followed by 26.9 days in 2008, 24.2 days in 2001, and 24.0 days in 2010. The heat wave distribution was relatively higher in agricultural areas, valleys, and rural areas. The topography of Milyang contains more mountainous slope (51.6%) than flat (19.7%), while large-scale valleys (12.2%) are distributed across some of the western region. Correlation analysis between heat wave and spatial characteristics showed that the correlation between forest area land cover and number of heat wave days was negative (-0.109), indicating that heat wave can be mitigated. Topographically, flat areas and heat wave showed a positive correlation (0.305). These results provide important insights for urban planning and environmental management for understanding the impact of land development and topographic change on heat wave.

• Journal of the Korean GEO-environmental Society
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• v.16 no.1
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• pp.45-53
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• 2015

This study has obtained Soil Water Retention Curve (SWRC) of the unsaturated soil from the volumetric pressure plate extractor test and the triaxial compression tests was also conducted. By using the rainfall data measured in the site the seepage analysis of unsteady flow was performed with the program of SEEP/W in Geostudio 2007 and stability of the slope was analyzed with SLOPE/W program. Results of analyses show that shear strength of the unsaturated soil increases with the increase of matric suction. And it was also found that the net volumetric stress and the apparent cohesion increased with the matric suction. The seepage analysis of rainfall represents that the increasing rate of negative pore pressure at the zone of large negative pore pressure is appeared to be high even though lower rainfall intensity, but this tendency declines with ground depth. The stability analysis of slope was carried out for the actual plane of failure with the data representing the field condition. The factor of safety thus calculated was about unity (1.0) or just below, which means that the adopted method of analysis is in good agreement with the field condition.

• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.259-266
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• 2015

Observed trends in climate change, globalization and an aging population have an effect on public health conditions in Korea, prompting a reevaluation of current environmental regulations. In this study, we evaluated the performance of the total coliform (TC) standard, which is the only microbiological standard in the current regulation regime for hot spring water, by estimating correlation with the presence/absence of Legionella, a non-fecal opportunistic pathogen with heat-tolerance. Microbiological data in 7 studies that surveyed Legionella in hot spring waters were subjected to meta-analyses with the odds ratio (OR) as the effect size. The presence/absence of Legionella was significantly correlated to TC levels [OR = 3.1(1.5–6.4, 95% CI), p = 0.002]. Due to there being no direct explanation as to the reason for the occurrence of TC, mesophilic fecal bacteria, being coupled with Legionella presence, the mechanism of the correlation between the two kinds of bacteria was further investigated. Legionella presence was more prevalent with a high heterotrophic plate count [HPC; 4.0(2.2–7.2); p < 0.001] and water temperature [4.3(1.4–13.6), p = 0.011] when the temperature range was <40℃. However, it was reverse-correlated with water temperature when the temperature was >50℃ [0.2(0.1–0.4), p < 0.001]. Therefore, bacterial standing crops in hot spring waters appear to be determined by water temperature in general, and this forces TC and Legionella levels be correlated. In accordance with this relationship, HPC rather than TC reflect the levels of non-fecal contamination better. Therefore, employing HPC as the sole microbiological standard, or adding HPC into the current standard of hot spring water assessment, is suggested as a proactive measure to prevent health issues arising from contamination.

• Journal of the Korean GEO-environmental Society
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• v.10 no.4
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• pp.15-24
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• 2009

Korea is known to have seasonal frost during winter and the effect of low temperatures and water may cause a weakening of pavements. For that reason, frost protection layers have been constructed in pavements to avoid damage caused by frost action. The practies established in USA and Japan have been adopted as anti-frost design methods in Korea. However, the characteristics of Korean soils are different. Additionally, there is no formulation of a reasonable equation for frost penetration depth and the criterion to identify potentially frost-susceptible soils in present pavement design manuals in Korea. Therefore, adequate pavement design procedures in seasonal frost areas, as well as construction and maintenance practices are required. In this paper, frost penetration depths along national roads in Korea were measured and analyzed over several years. The frost penetration depth was analyzed with respect to the provinces of Korea and sunny/ shaded areas. Additionally, measurement results were compared to the formula of the US Army Corps of Engineers and Ifukube in Japan.

• Journal of Environmental Policy
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• v.12 no.4
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• pp.119-132
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• 2013

Hosta longipes is one of the most popular ornamental perennials in use in Korea today, and is mainly used as a groundcover plant in urban shaded places. In this study, the pytoremediation effect of Hosta longipes was tested using four concentrations (Control, 100, 250 and $500mg{\cdot}kg^{-1}$) of Cd, Pb and Zn in soil. The plants were planted in $300mm{\times}200mm{\times}250mm$ drainless-containers, which were filled with a artificial amended soil for 7 months. The results showed that the contents of heavy metals cadmium and lead in the shoot of Hosta longipes increased with increasing heavy metal concentration levels exception of zinc. The amount of zinc, cadmium, and lead accumulated in roots were increased with heavy metal concentration levels up in soil. The shoot/root ratios(TF; translocation factor) values were found to be more than 80% of total Zn, Cd, and Pb take up by Hosta longipes. These results indicated that root is the major part for accumulation of heavy metal. The removal contents of zinc, cadmium, and lead increased significantly with the increasing heavy metal concentration in the soil, which was planted with Hosta longipes. The heavy metal concentration accumulation in plant/soil ratios (BF; bioaccumulation factor) values for three metals were found to be more than 30% in cadmium and lead, but lower in zinc treatments. The different responses of Hosta longipes suggest that in heavy metal contaminated soils the plant adsorbs available metals depending on the concentration soils in which they are present. Therefore, this species can be an efficient phytoremediator for soils contaminated with cadmium and lead in urban shaded places.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1430-1434
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• 2005

금강 유역과 같이 복잡한 하천유역 시스템의 관리를 위해서는 시스템 요소들을 통합적으로 분석할 수 있는 효과적인 의사결정지원 도구가 필요하다. K-MODSIM 모형은 단기 물관리, 장기 운영계획, 가뭄 대비계획 및 물관련 분쟁 해결을 위해 보다 개선된 유역관리 전략을 수립하기 위한 컴퓨터 기반 도구로 개발되었으며, 본 연구에서는 K-MODSIM 모형에 저수지 운영률을 반영하여 유역의 용수배분을 평가하였다. 유역 저수지군 운영 환경 및 제약조건을 반영한 네트워크를 구성한 후, 두 단계의 모형 검정을 수행하였다. 먼저 물리적 검정을 통해서 전체 대상 수계의 상하류 물수지를 검토하고, 다음 단계인 운영 측면의 검정에서 물리적으로 나타나는 상황이 댐 운영이나 제약 조건 등에 부합하는지의 여부를 검토하였다. 대청댐과 용담댐의 통합 운영을 위한 최적 운영률의 개발은 동적계획법 소프트웨어인 CSUDP를 이용하여 수행하였으며, 여기서 사유한 접근법은 음해 추계학적 동적계획법이다. 이 접근방법은 유입량 시계열을 추계학적으로 모의발생시키고, CSUDP 모형은 모의발생시킨 유입량 시계열에 대한 최적운영률을 찾기 위해 사용하며, CSUDP의 최적화 결과에 대한 통계적인 분석을 통해 월단위 운영률을 도출하였다. K-MODSIM 모형에 저수지 운영률을 반영하여 유역의 용수배분을 평가하였다. 유역 저수지군 운영 환경 및 제약조건을 반영한 네트워크를 구성하고, 대청댐과 용담댐의 통합 운영을 위한 최적연계 운영를을 개발하여 다음과 같은 운영 시나리오들을 개발하고 평가하였다. $\cdot$ 금강수계에 대한 용당댐의 영향 평가 $\cdot$ 댐 연계운영시 수요량 변화에 따른 영향 평가 $\cdot$ 하도추적을 고려한 일별모형의 검증 개발된 운영률과 하도추적방법을 K-MODSIM 모형에서 검증하기 위해서 vb.net 스크립트 파일을 개발하여 적용하였다.L이하로 이를 유등천 상류부에 공급할 경우 유등천의 수질은 BOD 6.7mg/L, TN 9.80mg/L, TP 0.90mg/L를 나타낼 것으로 예측된다. 고도처리시설의 도입 후 금강 합류점에서 갑천의 예측 BOD는 7.4mg/L로 현재 9.0mg/L에 비하여 개선되지만 이는 금강수계 오염총량 관리계획의 시$\cdot$도 경계지점 목표수질인 5.9mg/L를 만족시키지 못하므로, 이를 만족시키기 위해서는 방류수 BOD 7.2mg/L이하로 처리해야 할 것으로 판단된다.which support only concepts or image features.방하는 것이 선계기준에 적합한 것으로 나타났다. 밸브 개폐에 따른 수압 변화를 모의한 결과 밸브 개폐도를 적절히 유지하여 필요수량의 확보 및 누수방지대책에 활용할 수 있을 것으로 판단된다.8R(mm)(r^2=0.84)$로 지수적으로 증가하는 경향을 나타내었다. 유거수량은 토성별로 양토를 1.0으로 기준할 때 사양토가 0.86으로 가장 작았고, 식양토 1.09, 식토 1.15로 평가되어 침투수에 비해 토성별 차이가 크게 나타났다. 이는 토성이 세립질일 수록 유거수의 저항이 작기 때문으로 생각된다. 경사에 따라서는 경사도가 증가할수록 증가하였으며 $10\% 경사일 때를 기준으로 $Ro(mm)=Ro_{10}{\times}0.797{\times}e^{-0.021s(\%)}$로 나타났다.천성 승모판 폐쇄 부전등을 초래하는 심각한 선천성 심질환이다. 그러나 진단 즉시 직접 좌관상동맥-대동맥 이식술로 수술적 교정을 해줌으로써 좋은 성적을 기대할 수 있음을 보여주었다.특히 교사들이 중요하게 인식하는 해방적 행동에 대한 목표를 강조하여 적용할 필요가 있음을 시사하고 있다.교하여 유의한 차이가 관찰되지 않았다. 또한 HSP 환자군에서도 $IL1RN^{*}2$ allele 빈도와

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.3
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• pp.27-35
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• 2018

In the mandatory application of the CPTED, only negative parts of urban parks and vegetation were reflected. Therefore, this study tries to present the positive effects of urban parks and vegetation. The purpose of this study is to demonstrate the effects of urban parks and vegetation on crime occurrence and to suggest the planning implications of this to CPTED based on theory related to crime, environmental psychology, and crime occurrence analysis. This study used the crime occurrence data of Seoul, NDVI, population, distance from urban park, floating population, and the like. This study collected data from the Statistics Korea, the local government, and Landsat 8 satellite images provided by the USGS and created data of environmental variables and social variables by district using ArcGIS and statistical program. Literature analysis, correlation analysis, regression analysis, and geographically weighted regression were used to determine the relationship between crime occurrence and environmental variables, and to discuss its implication. It was found that crime occurrence has a relationship with the total population (${\beta}=.663$), the number of amusement facilities (${\beta}=.447$) and the area of a police station jurisdiction (${\beta}=.395$). This confirms that a crime rate is low when the floating population is large (${\beta}=-.241$) and vegetation vitality is high (NDVI, ${\beta}=-.281$). Vegetation vitality (NDVI) is effective in lowering violence through psychological stabilization, strengthening territoriality and improving regional image. The implications for the allocation of urban park and vegetation, program and management plan of urban park and vegetation to reduce crime occurrence have therefore been presented.