• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.356-356
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• 2020

주거시설 확장 및 도심 내 인프라 구축을 위한 지속적인 산지 개발과 기후변동성 확대로 발생하는 게릴라 국지성 집중호우 등으로 인해 토석류의 발생가능성은 지속적으로 확대되고 있다.(kim et al., 2008) 그러나, 현재 국내의 토석류 방재시설에 대한 설치는 아직 미흡한 실정이며 아직 경사지 재해 발생 위험지역에는 방재시설 설치가 필요하다. 지자체의 제한된 예산으로는 필요한 모든 지역에 설치가 불가하기 때문에 순차적으로 효율적인 설치가 이루어질 필요가 있다. 이에 본 연구에서는 도심지 내 소규모 산지에 대한 효율적인 설치방안을 모색하기 위해서 방재시설 설치 이후 토석류의 거동을 수치모의를 통해 방재시설 설치의 효율성을 분석하였다. 도심지 내 위치한 토석류 발생이력이 있는 소규모 산지의 토석류의 특성을 조사한 결과, 주요 발생원인은 국지성 집중호우로 인한 지반 약화로 인해 급경사를 이루고 있는 암반층 상단에 분포한 퇴적층의 붕괴가 주요 원인으로 나타났다(Kang et al, 2014) 조사결과에 근거하여 해당 유역에 대한 토석류 발생의 유입조건을 산정하였으며 유입조건에 대해 토석류 거동 예측 2차원 해석 소프트웨어인 FLO-2D를 사용하였다. 수치모의를 수행하여 방재시설이 미설치된 상태에서 발생한 토석류의 거동을 실제 발생한 토석류와 비교하였다. 또한, 수치모의에서 방재시설의 구현이 제한되므로 4가지 방재시설(교란사면용 토석류 방지시설, 울타리형 토석류 방지시설, 토사유출 저감용 지오셀, 토석류 방재장치)에 대해 경계조건의 변경을 통해 간접적으로 구현해 결과를 분석하였다. 방재시설은 종류 및 설치위치에 따라 토석류에 대한 피해저감효과가 상이하게 나타났다. 토석류 방재장치를 토석류 발생위치 전방 50 m 지점에 토석류 방재장치를 설치한 경우, 토석류의 유속이 20% 감소하여 피해범위는 36% 감소하였으며, 전방 200 m 지점에 설치한 경우, 피해범위가 14% 감소하였다. 검토한 4가지의 토석류 방재시설 중 토석류 방재장치가 가장 효율적인 결과를 나타냈다. 향후에는 피해범위에 대한 조건 외에 시공 및 유지관리 등에 대한 경제성검토를 한다면 종합적으로 방재시설 효율성을 검토할 수 있을 것으로 본다.

• Korean Journal of Ecology and Environment
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• v.40 no.3
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• pp.481-488
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• 2007

This study covers the relationship between land use and water quality items. The kinds of land used in this study were almost agricultural areas with paddy fields and mountains. We set up zones at intervals of 200 m along 48 watersheds all over the country. The analysis showed high relationship between the water quality and the land use specially on the areas in the 400 m radius from the stream so that the areas needed to have strict managements. In the cases of residential area and upland, the positive correlation had a tendency to be lower when they were farther away from the stream. It depended on the increase of rainfall during July and August which affected on the water quality of reservoirs. The correlation analysis of paddy fields resulted in negative relationship, which indicated that paddy fields did not have negative effect on the quality of the stream. Through adequate irrigation and Management, paddy fields may be led to have positive effect on the quality of the reservoirs. In the case of forest, it also resulted in negative correlation so it was concerned as a positive factor which helped to improve water quality. Furthermore more than 00% of the land used in this study is comprised of forest so that it would have a positive effect on the reservoir management.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.1
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• pp.68-79
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• 2008

Because local cities are different from large cities, they need to reflect their own characteristics of housing market. Thus in order to obtain useful implications for the establishing sound housing market in Jinju City, this paper investigated the characteristics of spatial distribution and determinant factors that affect apartment price in Jinju City. GIS representation of the apartments showed that most of old and small apartments were built in 'land readjustment project' areas executed in 1970s. On the contrary, new and large scale apartment complexes were built quite recently and distributed in the western and southern parts of the city. Next, in order to examine the factors which affect apartment price, this paper subtracted firstly several variables from the related studies. However in order to avoid multi-colinearity, variables were summarized by means of factor analysis. Then, setting apartment price as a dependant variable, 12 hedonic price models were established with 33 independent variables. As results, building age, floor area, accessibility to university and hospital, accessibility to arterial road, and stair-type building were turned out to be significant. These results will be used in making the supply and allocation plan of urban facilities and housing. Finally as conclusions this paper emphasized the need of periodic analysis of local housing market and establishing detailed housing information systems.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.2
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• pp.120-131
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• 2009

This study measured the centripetal force and effective scope of the population spread from urban center and subcenters in order to diagnose the urban spatial structure of the formation of a multicentric city structure in Busan. The study analyzed the variability of the determination coefficient value (R square) with a negative exponential function derived from the population density model by extending the circular region into 5-km units. The aim of this study was to measure changes in the effective scope of the population centripetal force of the urban center and subcenter in 5-year intervals from 1995 to 2005 using census data. The explanatory adequacy of the population density function was examined with the bias of the function to calculate the distance error between the real location of the urban center and the optimal location, according to the population density function. To summarize the results, the value for the area of Jungangdong showed a continuous reduction, whereas Seomyeon (Bujeondong) maintained explanatory adequacy without a large change. As a whole, Busan was in the process of continuous diversification, in spite of its reduced population. Therefore, it appears necessary to strengthen the function of the urban center and subcenter and to supply adequate dwelling zones close to downtown to form a more efficient urban spatial structure. The results of the present study will be utilized as basic data for the formulation of a political approach to the efficient reorganization of spatial structure by correlating concrete spatial information with the population variability of Busan's urban center and subcenter.

• The Korean Journal of Ecology
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• v.27 no.3
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• pp.185-192
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• 2004

Vegetation established through the natural process, such as Quercus mongolica, Pinus densiflora, Q. variabilis, Q. acutissima, Carpinus laxiflora, Q. aliena and Q. serrata communities and artificially introduced vegetation, which are composed of Larix leptolepis and P. rigida plantations, are established in the mountainous land of the Mt. Songnisan National Park. On the other hand, the developed lands, which are consisted of agricultural folds, residential areas, commercial areas related to tourism, etc. appear in the lowland around streams. Based on the spatial distribution of vegetation, the southern district, which is attributed to Naesongni-myun by administrative system, showed higher natural degree and vegetation diversity. However, most of the other districts, which are attributed to Cheongcheon- and Chilseong-myuns, are covered with the Korean red pine forest, a product of artificial influence, and plantation also occupied higher percentage. Thereby both vegetation diversity and natural degree are lowering. A result of ordination by DCA showed that sands tended to be arranged by depending on the topographic condition. Species diversity of plant communities was higher in broad-leaved stands rather than in coniferous ones and in stands of the early stage than in ones of the late stage. The result of analysis on vegetation dynamics implied that vegetation of this region would be dominated by Carpinus laxiflora, Quercus mongolica and Pinus densiflora communities in the future. However, considered occurrence the of disturbance and response of vegetation on that, this estimation may different somewhat from an actual situation. Conservation strategies of the Mt. Songnisan National Park were discussed in viewpoints of landscape ecology, and conservation of major plant communities and biodiversity.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.34-39
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• 2006

The land use pattern, water quality and vegetation were investigated in the six tributaries, including Hanggeumcheon and Satancheon of the Namhan hydrosphere, Iksancheon, Jeonjucheon and Gosancheon of the Mankyung hydrosphere as well as Jongeupcheon of the Dongjin hydrosphere. Forest and farmland area were extensive in Hanggeumcheon, Satancheon and Gosancheon. Farmland and livestock area were wide in Iksancheon. Jeonjucheon were occupied with broad urban. Industrial and urban area were extensive in Jongeupcheon. The loading amounts of biochemical oxygen demand (BOD), total nitrogen (T-N), total phosphorus (T-P) of Iksancheon and chemical oxygen demand (COD) of Jeonjucheon were determined to be very high, respectively. The quality of water in Hanggeumcheon, Satancheon and Gosancheon were determined to be good quality. The species diversity was lower in the down stream than in the upper stream except for the Gosancheon. Life form of plane were mostly perennial plane in the upper stream and annual plants in the down stream of rivers. It was estimated that there is high level of disturbance in the down stream of rivers. The quality of water was significantly correlated with farmland and forest area. In conclusion, human impact, such as farmland and housing lot exerted an influence on the disturbance of down stream and the water quality of rivers.

• Journal of the Korean Regional Science Association
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• v.35 no.4
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• pp.61-73
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• 2019

Urban development and densification have led to the Urban Heat Island Effect, in which the temperature of urban space is higher than the surrounding areas, and the intensity is increasing with climate change. In addition, when the city's air temperature rises in summer, low-income, elderly population, and socially vulnerable people who have health problems lack the ability to cope with the elevated heat environment. Therefore, this study aimed to identify the urban heat island area of Seoul through Hotspot analysis, which is a spatial statistics technique, and explored physical environments, demographic and socioeconomic characteristics of urban heat island effect areas using logistic regression models. This study performed urban heat island hotspot analysis using the average air temperatures of the 423 administrative dongs in Seoul. Analysis results identified that the urban heat islands were concentrated in Jung-gu, Jongno-gu, Yongsan-gu, and Yeongdeungpo-gu. Logistic regression analysis results indicated that urban heat island areas of Seoul were affected by residential floor area ratio, commercial facility floor area ratio, overall floor area ratio, impervious surface ratio, and normalized difference vegetation index(NDVI). In addition, as a result of analyzing the vulnerable area of thermal environment considering the demographic and socioeconomic characteristics of the heat island area, urban heat island areas of Seoul were significantly associated with the proportion of low-income elderly living alone. The result of this study provided useful insights for urban thermal environmental design and policy development that could improve the thermal environment for the socially disadvantaged urban population.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.5
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• pp.9-18
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• 2013

Urban parks are public spaces that provide various services for any urban resident to use and enjoy. Parks should be fairly distributed so that the urban parks can be equally used amongst different regions, generations and classes. Researches on spatial distribution of urban parks have been continuously conducted from the past based on the principles of fairness with variety, and it was evident that their techniques have become more elaborate and sophisticated. Yet, there have been limitations in the analysis of residents who are the main users of the urban parks. The research done so far was unable to apply the real number of the residents and it was carried out by only classifying and analyzing the population by the same scale(grid in the same sizes), postal(zip) code and administrative district. The actual population that resides within the usable range of urban parks was not used. This study analyzes and evaluates the spatial distribution that the residents can use on foot, by utilizing the service areas and the residents' registration data by addresses. In this study, to analyze the square measure of the service areas of neighborhood parks in Daegu Metropolitan City and the number of residents within and outside of the service area, network analysis techniques were employed and the residents' registration data were utilized. Major findings were that the Square measure of service areas of neighborhood parks turned out to be 31.23% of the square measure of the residential areas and also, that only 43.03% of the population of the Daegu Metropolitan area lives within the service areas of the neighborhood parks.

• Journal of Cadastre & Land InformatiX
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• v.47 no.2
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• pp.19-37
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• 2017

Visible Infrared Imaging Radiometer Suite Day-Night Band (VIIRS-DNB) data provides a much higher capability for observing and quantifying nighttime light (NTL) brightness in comparison with Defense Meteorological Satellite-Operational Linescan System (DMSP-OLS) data. In South Korea, there is little research on the detection of NTL brightness change using VIIRS-DNB data. This study analyzed the spatial distribution and change of NTL brightness between 2013 and 2016 using VIIRS-DNB data, and detected its spatial relation with possible influencing factors using regression models. The intra-year seasonality of NTL brightness in 2016 was also studied by analyzing the deviation and change clusters, as well as the influencing factors. Results are as follows: 1) The higher value of NTL brightness in 2013 and 2016 is concentrated in Seoul and its surrounding cities, which positively correlated with population density and residential areas, economic land use, and other factors; 2) There is a decreasing trend of NTL brightness from 2013 to 2016, which is obvious in Seoul, with the change of population density and area of industrial buildings as the main influencing factors; 3) Areas in Seoul, and some surrounding areas have high deviation of the intra-year NTL brightness, and 71% of the total areas have their highest NTL brightness in January, February, October, November and December; and 4) Change of NTL brightness between summer and winter demonstrated a significantly positive relation with snow cover area change, and a slightly and significantly negative relation with albedo change.

• Economic and Environmental Geology
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• v.38 no.3 s.172
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• pp.221-236
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• 2005

In order to investigate the contamination levels and dispersion patterns of heavy metals such as Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn by urbanization, soils beneath roadside-trees and leaves of Ginkgo biloba were collected from Seoul area during October to November in 2001. All tree leaves were grouped into washed and unwashed ones. The pH of most soil ranges from 6 to 9 indicating a weak acidic and alkaline. The element couples of Cd-Co, Cr-Ni and Zn-Cu-Pb have good correlation in soils, and contamination sources of Cd-Co, Cr-Ni and Zn-Cu-Pb could be similar. High correlation coefficients among Pb, Cu and Zn in G. biloba indicates that these elements show the similar behavior during the metabolism processes. From the results of pollution index calculation for soils, industrialized and heavy traffic area were severly polluted by heavy metals such as Cd, Cu, Pb and Zn. By the discriminant analysis, industrialized and heavy traffic areas are enriched in the order of Ni> Cr> Pb. Cadmium is useful to discriminate between industrialized and heavy traffic areas, Co and Pb are highly enhanced in heavy traffic area.