• Journal of Korea Water Resources Association
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• v.35 no.1
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• pp.97-108
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• 2002

The use of land at the time of investigation of groundwater quality in the rapidly urbanized Bu-chon city is classified into 5 categories based on the change process of land use. The difference in groundwater quality according to the land use and its usage period is tested by non-parametric statistical procedures. The seven constituents of water quality with the highly frequent detection in the area for this study are used for the statistical test. The shallow groundwater quality within the areas of the same land use at the time of investigation varies significantly according to the period of land usage. The concentration of KMnO$_4$consumed and hardness is significantly higher in the old residential area (of more than 20 years old) than in the younger one (of less than 10 years old). The quality of the shallow groundwater is also significantly different among the three categories with the similar period of land usage (of more than 15 years old). The concentration of No$_3$-N, hardness and total solid is significantly higher in the residential area than in the agricultural one (namely, the area used as paddy fields 2 to 5 years ago). The median concentration of these constituents is 2.2 to 3.8 times higher in the residential area than in the agricultural one. The concentration of NO$_3$-N, KMnO$_4$, consumed and Cl is significantly higher in the industrial area than in the agricultural one. The median concentration of these constituents is 5.5 to 18 times higher in the industrial area than in the agricultural one. The concentration of KMnO$_4$consumed is significantly higher in the industrial area than in the residential area. The median concentration of these constituents is 12 times higher in the industrial area than in the residential one. The spatial distribution of shallow groundwater quality in the rapidly urbanized area is closely related to the period of land usage as well as the land use, which is presumed to be attributed to the difference in the concentration and leakage rate of the contaminants leaking from damaged sewer into shallow groundwater.

• Korean Journal of Remote Sensing
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• v.33 no.6_3
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• pp.1187-1196
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• 2017

Despite the continuing effort to estimate the value of function and services of ecosystem, most of the researches has used low and medium resolution satellite imagery such as MODIS or Landsat. It means that the researches to measure the ecosystem service value using VHR (Very High Resolution) satellite imagery have not been performed much, while the source of available VHR imagery is increasing. Thus, the aim of this study is to estimate and compare the result of ecosystem service value over Sejong city, S. Korea, which is one of the rapidly changed city, through the pixel-based and object-based classification analysis using VHR KOMPSAT-3 images, for more specific and precise information. In the result of the classification, forest and grassland were underestimated while agriculture and urban were overestimated in the pixel-based result compared to the object-based result. Furthermore, bare soil area was presented contrasting result that was increased in the pixel-based result, however, decreased in the object-based result. Using those results, ecosystem service values were estimated. The annual ecosystem service values in 2014 were $8.18 million USD(pixel-based) and $8.63 million USD(object-based), however, decreased to $7.80 million USD(pixel-based) and $8.62 million USD(object-based) in 2016. It is expected to use those results as a preliminary data when to make sustainable development plan and policy to improve the quality of life in the local level.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.2
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• pp.113-125
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• 2012

This research is aimed at evaluating the land surface characterization of KOMPSAT-3A middle infrared (MIR) data. Airborne Hyperspectral Scanner (AHS) data, which has MIR bands with high spatial resolution, were used to assess land surface temperature (LST) retrieval and classification accuracy of MIR bands. Firstly, LST values for daytime and nighttime, which were calculated with AHS thermal infrared (TIR) bands, were compared to digital number of AHS MIR bands. The determination coefficient of AHS band 68 (center wavelength $4.64{\mu}m$) was over 0.74, and was higher than other MIR bands. Secondly, The land cover maps were generated by unsupervised classification methods using the AHS MIR bands. Each class of land cover maps for daytime, such as water, trees, green grass, roads, roofs, was distinguished well. But some classes of land cover maps for nighttime, such as trees versus green grass, roads versus roofs, were not separated. The image classification using the difference images between daytime AHS MIR bands and nighttime AHS MIR bands were conducted to enhance the discrimination ability of land surface for AHS MIR imagery. The classification accuracy of the land cover map for zone 1 and zone 2 was 67.5%, 64.3%, respectively. It was improved by 10% compared to land cover map of daytime AHS MIR bands and night AHS MIR bands. Consequently, new algorithm based on land surface characteristics is required for temperature retrieval of high resolution MIR imagery, and the difference images between daytime and nighttime was considered to enhance the ability of land surface characterization using high resolution MIR data.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.1
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• pp.142-154
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• 2010

The purpose of this study is to analyze the effects of various spatial characteristics on the land surface temperature and to grasp the characteristics of thermal environment by types of urban area in Changwon, Gyeongsangnam-do. The spatial data were consisted LST, normalized difference built-up index(NDBI) and normalized difference vegetation index(NDVI) obtained from Landsat 5 TM and land use and land cover map classified from high resolution digital aerial photograph($10cm{\times}10cm$). The unit space for spatial analysis was built by $500m{\times}500m$ Vector GRID. According to the results of estimation of relationship between thermal environment and spatial characteristics, LST had the highest positive correlation with NDBI by 0.929 and had high positive correlation with impervious area ratio by 0.857. In order to analysis of thermal environment on land use, types of urban area were classified by 4 of residential focus area, industrial focus area, green focus area and mixed area. According to the results of analysis, mean LST of industrial focus area was showed the highest by $21.10^{\circ}C$. But mean LST of green focus area was analyzed the lowest by $18.85^{\circ}C$. In conclusion, the results of this study investigated the effects of spatial characteristics on urban thermal environment and can provide methods and basic informations about land use planning and development density restriction for reduction of urban heat.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.779-784
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• 2008

환경부에서 추진하고 있는 토지피복 중분류별 비점오염부하원단위를 산정하기 위한 사업 중 나지로 분류되는 채광지역의 비점오염부하를 측정하였다. 비점오염부하는 강원도 삼척시 도계읍의 도계 작업장(석탄)과 태백시 장성동의 태백 저탄소 등 2곳의 채광지역에서 2007년 9월부터 12월까지 2회의 강우유출사상을 대상으로 측정하였다. 2회 강우사상 동안 총강수량은 도계 작업장에서 149 mm이었으며 태백 저탄소에서 201 mm이었다. 유출량은 수위계와 유량계로 5분 단위로 측정하였으며, 수질시료는 자동채수기로 2시간 간격으로 채취하였다. 수질시료는 환경부의 공정시험법에 따라 SS, BOD, CODcr, T-N, T-P, 그리고 TOC 농도를 분석하였다. 그리고 일부의 시료에 대해서는 Zn, Cb, Cu, 그리고 Pb의 농도를 분석하였다. 도계 작업장의 유량가중평균농도는 갱내수의 수질에 많은 영향을 받는 것으로 나타났다. 도계작업장의 일평균유량가중평균농도는 SS $86.3{\sim}94.9\;mg/{\ell}$, BOD $3.8{\sim}7.6\;mg/{\ell}$, COD $26.9{\sim}51.6\;mg/{\ell}$, T-N $1.5{\sim}2.1\;mg/{\ell}$, T-P $0.2\;mg/{\ell}$ 그리고 TOC $1.8{\sim}2.3\;mg/{\ell}$로 나타났다. 태백 저탄소의 일평균유량가중평균농도는 SS $16.5{\sim}66.6\;mg/{\ell}$, BOD $7.4{\sim}9.8\;mg/{\ell}$, COD $41.1{\sim}66.7\;mg/{\ell}$, T-N $0.7{\sim}1.1\;mg/{\ell}$, T-P $0.2\;mg/{\ell}$ 그리고 TOC $1.7{\sim}2.6\;mg/{\ell}$로 나타났다. 중금속의 농도는 모든 시료에서 환경부의 배출허용기준농도보다 낮게 나타나거나 검출되지 않았다. 도계 작업장의 일오염부하는 SS $1,368.8{\sim}1,984.1\;kg/day$, BOD $56.6{\sim}128.9\;kg/day$, COD $385.7{\sim}933.7\;kg/day$, T-N $23.4{\sim}44.5\;kg/day$, T-P $2.1{\sim}4.8\;kg/day$ 그리고 TOC $24.3{\sim}39.3\;kg/day$이었다. 태백 저탄소의 일오염부하는 SS $8.2{\sim}162.1\;kg/day$, BOD $2.6{\sim}15.3\;kg/day$, COD $13.8{\sim}83.6\;kg/day$, T-N $0.2{\sim}3.1\;kg/day$, T-P $0.1{\sim}0.6\;kg/day$ 그리고 TOC $0.7{\sim}4.4\;kg/day$로 나타났다. 본 연구는 2회의 강우유출사상에 대하여 측정한 자료이므로 연평균농도나 연평균오염부하로 활용하기는 어렵다. 그러나 석탄광산지역의 비점오염부하를 이해하는데 활용할 수 있으며 또한 장기적인 연구자료로 활용하여 석탄광산지역의 비점오염원단위의 산정에 유용한 자료로 활용할 수 있다.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.4
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• pp.113-126
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• 2021

This study was conducted to analyze the forest status and deforestation area changes of the DMZ region in North Korea based on satellite images. Using growing and non-growing season's RapidEye satellite images, land cover of the North Korean DMZ was classified into stocking land(conifer, deciduous, mixed), deforested land(unstocked mountain, cultivated mountain, bare mountain), and non-forest areas. Deforestation rates in the Yeonan-baecheon, Beopdong-Pyeonggang, Heoyang-Geumgang and Tongcheon-Goseong district were calculated as 14.24%, 16.75%, 5.98%, and 16.63% respectively. Forest fire and land use change of forest were considered as the main causes of deforestation of DMZ. Changes in deforestation area were analyzed through Google Earth images. As a results, it was shown that the area of deforestation was on a decreasing trend. This study can be used as basic data for establishing inter-Korean border region's forest cooperation strategies by providing forest spatial information on the North Korea's DMZ.

• 한국공간정보시스템학회:학술대회논문집
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• 2005.11a
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• pp.17-22
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• 2005

Generally, pixel-based classification, utilize the similarity of distances between the pixel values in feature space, is applied to land use mapping using satellite remote sensing data. But this method is Improper to be applied to the very high resolution satellite data (VHRS) due to complexity of the spatial structure and the variety of pixel values. In this paper, we performed the hierarchical classification of VHRS imagery by data fusion, which integrated LiDAR height and intensity information. MLC and ISODATA methods were applied to IKONOS-2 imagery with and without LiDAR data prior to the hierarchical classification, and then results was evaluated. In conclusion, the hierarchical method with LiDAR data was the superior than others in VHRS imagery and both MLC and ISODATA classification with LiDAR data were better than without.

• Spatial Information Research
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• v.19 no.6
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• pp.43-54
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• 2011

This study proposes a rule-based image classification method for the time-series analysis of changes in the land surface of the Seongnam-Yongin area using satellite-image data from 2000 to 2009. In order to identify the change patterns during each period, 11 classes were employed in accordance with statistical/mathematic rules. A generalized algorithm was used so that the rules could be applied to the unsupervised-classification method that does not establish any training sites. The results showed that the urban area of the object increased by 145% due to housing-site development. The image data from 2009 had a classification accuracy of 98%. For method verification, the results were compared to land-cover changes through Post-classification comparison. The maximum utilization of the available data within multiple images and the optimized classification allowed for an improvement in the classification accuracy. The proposed rule-based image-classification method is expected to be widely employed for the time-series analysis of images to produce a thematic map for urban development and to monitor urban development and environmental change.

• Korean Journal of Remote Sensing
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• v.36 no.6_2
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• pp.1567-1577
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• 2020

Urban land cover classification is role in urban planning and management. So, it's important to improve classification accuracy on urban location. In this paper, machine learning model, Support Vector Machine (SVM) and Artificial Neural Network (ANN) are proposed for urban land cover classification based on high resolution satellite imagery (KOMPSAT-3A). Satellite image was trained based on 25 m rectangle grid to create training data, and training models used for classifying test area. During the validation process, we presented confusion matrix for each result with 250 Ground Truth Points (GTP). Of the four SVM kernels and the two activation functions ANN, the SVM Polynomial kernel model had the highest accuracy of 86%. In the process of comparing the SVM and ANN using GTP, the SVM model was more effective than the ANN model for KOMPSAT-3A classification. Among the four classes (building, road, vegetation, and bare-soil), building class showed the lowest classification accuracy due to the shadow caused by the high rise building.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.1
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• pp.158-167
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• 2006

The object of this study is to detect of land-cover change in western DMZ and vicinity. This was performed as a basic study to construct a decision support system for the conservation or a sustainable development of the DMZ and Vicinity near future. DMZ is an is 4km wide and 250km long and it's one of the most highly fortified boundaries in the world and also a unique thin green line. Environmentalists want to declare the DMZ as a natural reserve and a biodiversity zone, but nowadays through the strengthening of the inter-Korean economic cooperation, some developers are trying to construct a new-town or an industrial complex inside of the DMZ. This study investigates the current environmental conditions, especially deforestation of the western DMZ adopting remote sensing and GIS techniques. The Land-covers were identified through the linear spectvral mixture analysis(LSMA) which was used to handle the spectral mixture problem of low spatial resolution imagery of Landsat TM and ETM+ imagery. To analyze quantitative and spatial change of vegetation-cover in western DMZ, GIS overlay method was used. In LSMA, to develop high-quality fraction images, three endmembers of green vegetation(GV), soil, water were driven from pure features in the imagery. Through 15 years, from 1987 to 2002, forest of western DMZ and vicinity was devastated and changed to urban, farmland or barren land. Northern part of western DMZ and vicinity was more deforested than that of southern part. ($52.37km^2$ of North Korean forest and $39.04km^2$ of South Korean were change to other land-covers.) In case of North Korean part, forest changed to barren land and farmland and in South Korean part, forest changed to farmland and urban area. Especially, In North Korean part of DMZ and vicinity, $56.15km^2$ of farmland changed to barren land through 15 years, which showed the failure of the 'Darakbat' (terrace filed) project which is one of food increase projects in North Korea.