• 한국환경복원기술학회지
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• 제15권5호
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• pp.129-144
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• 2012

This study was conducted to understand the community characteristics of benthic macroinvertebrates according to Growth Environment at 6 Palustrine Wetlands in a rural area. As growth environment factors, size, water depth, water inlet and water outlet, land-use and water environment was analyzed. Two years' quantitative collection of benthic macroinvertebrate was carried out, and it executed community analysis and ESB index calculation and also carried out twinspan, MDS and correlation analysis. As a result, the collected benthic macroinvertebrate was 1254 individuals with 3 Phylums, 6 Classes, 14 Orders, 35 Families, 52 Genera and 61 Species. Odonata and Coenagreionidae had the highest species and individuals. Dominance Index was 0.252~0.698, Diversity Index was 1.661~2.902, Evenness Index was 0.414~0.724, and Species Richness Index was 1.990~6.224. As a result of community analysis, when correlation analysis was executed, Dominance Index had the opposite tendency with Diversity Index and Evenness Index, which had the same tendency with the previous studies. When ESB Index was calculated, Grade 2 (polluted) had the highest species with 48 species (78.7%). It is determined from the Environmental quality evaluation and saprobity evaluation result according to ESB index that there is a need to revise environmental evaluation system more specifically. As a result of MDS analysis, the subject spots A and D had the highest similarity, and the subject spot E and D had a relatively high similarity. The life environment that is the closest related with species diversity is estimated by the land-use. As for number of Individual, it seems to have the closest relation with inlet, which is to be determined as a characteristics of Palustrine Wetland. Through such investigation, this study is expected to be utilized for various types of habitats including ecological pond and to be utilized for the increase of species diversity in rural areas.

• 한국수자원학회논문집
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• 제47권2호
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• pp.183-194
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• 2014

최근 수자원 취약성에 대한 논의 및 지속 가능한 개발개념에 적합한 지수 개발이 활발히 이루어지고 있다. 이러한 지수를 바탕으로 현재 또는 미래의 수자원 취약성을 판단하고 진단하고 있다. 본 연구는 자료의 확보가 가능한World Bank, 취약성-탄력성지수(Vulnerability Resilience Indicator, VRI), 환경지속 가능성지수(Environmental Sustainability Index, ESI)에서 사용된 수자원 평가 관련 지표들을 활용하여 우리나라를 포함한 전 세계 152개 국가의 수자원 취약성 순위를 도출했다. 이러한 지표를 바탕으로 수자원 취약성의 정량적 평가를 위해 TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) 기법을 적용하여 국가 별 수자원 취약성을 지수화하고 취약성 순위를 도출하였다. 연구결과 우리나라는 152개국 중 88위로 나타났고, 대륙 별 비교 시 오세아니아가 취약성이 낮았고, 아프리카는 취약성이 심각한 것으로 나타났다. 주요 국가 비교 시, 미국, 일본, 우리나라, 중국 순으로 취약성의 정도가 심각했다. 따라서 본 연구는 국가 별 수자원 취약성 순위를 통해 우리나라의 상황을 파악하고 국가의 수자원 계획 수립 및 대책을 제시할 수 있는 자료로 활용될 수 있을 것이다.

• 농촌계획
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• 제19권3호
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• pp.107-116
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• 2013

In this study, it provides the diagnostic index for the rural landscape formation. For the development of diagnostic index, this study first analyzed documents and papers on the landscape formation. Landscape types are also classified by their function and then landscape index was developed by AHP method. Classification system was categorized as three steps: 2 items for 1st step, 10 items for 2nd step, and 20 items(criteria) for 3rd step. In the survey of weighting values with AHP method, the analysis result for the first step showed that rural village landscape is more important than landscape around the village by approximately 20%. In the second step, residence is rated as the most important, followed by village tree planting, and then farmland around the rural villages, greenery, and water environment. In the third step, the feng shui is rated as the most important, followed by tree planting, village forest, culture, and history. While vehicle maintenance, village alleys and pedestrian facilities are rated lower. In index of the around the village, weighting value for index of the farm land and skyline has the highest value. While species richness, water quality and water resources were rated relatively low. In the future, the rural landscapes diagnosis index will be applied to measure the level of the rural villages landscapes and it is expected to propose political support for the landscapes formation.

• 한국조경학회지
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• 제27권5호
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• pp.138-149
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• 2000

The purpose of this study is to evaluate Suwon stream naturalness Index(S.N.I). and tofind out stats, problems and opportunities of the Suwon stream by assessment standard. Assessment standard is mainly based on physical structure of stream environment. the purpose evaluating sectors and elements are physical form and structure restoration of stream. To find out assessment standard of stream naturalness index, conceptual frame of assessment standard has been established, for which four sections, for example, longitudinal section, lateral section, stream bottom structure and water environment, have been selected. Overall stream naturalness index of the Suwon stream has been distributed at 3rd to 4th grade, and 3.3 of assessment index and mode were 3rd grade respectively. stream naturalness index of each section was as follows: Longitudinal section accounted for 3.7in average to be 4th grade, lateral section did 3.8 to be 4th grade, and water environment did 2.4 to be 2nd grade. Analysis of assessment outcome of stream naturalness index has checked status, problems and opportunities of corresponding stream. Assessment of stream naturalness index of the study provides useful information for restoration of close-to-nature stream, and furthermore has its meaning in checking problems and opportunities of Suwon stream.

• 대한원격탐사학회지
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• 제31권4호
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• pp.293-302
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• 2015

Water body extraction is significant for flood disaster monitoring using satellite imagery. Conventional methods have focused on finding an index, which highlights water body and suppresses non-water body such as vegetation or soil area. The Normalized Difference Water Index (NDWI) is typically used to extract water body from satellite images. The drawback of NDWI, however, is that some man-made objects in built-up areas have NDWI values similar to water body. The objective of this paper is to propose a new method that could extract correctly water body with built-up areas in before and after images of flood. We first create a two-element feature vector consisting of NDWI and a Near InfRared band (NIR) and then select a training site on water body area. After computing the mean vector and the covariance matrix of the training site, we classify each pixel into water body based on Mahalanobis distance. We also register before and after images of flood using outlier removal and triangulation-based local transformation. We finally create a change map by combining the before-flooding water body and after-flooding water body. The experimental results show that the overall accuracy and Kappa coefficient of the proposed method were 97.25% and 94.14%, respectively, while those of the NDWI method were 89.5% and 69.6%, respectively.

• 한국물환경학회지
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• 제22권5호
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• pp.748-756
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• 2006

Accurate and timely information on status and trends in the environment is necessary to shape sound water quality management policy and to implement water quality improvement programs efficiently. One of the most effective ways to communicate information on water quality trends to policy-makers, scientists, and the general public is with comprehensive water quality indices. The derivation and structure of a water quality index (WQI) for the classification of surface water quality is discussed. The WQI generally developed through the selection, transformation and weighting of determinants with rating curves based on legal standards and quality directives or guidelines. The representative pollutants should be included in the index, and the relationship between the quantity of these pollutants in the water and the resulting quality of the water should be based on scientific results. The WQI be simply and meaningfully formulated that nonscientifically trained users can easily become familiar with the framework of the system and use the output data to evaluate their own pollution problems.

• 한국수자원학회논문집
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• 제49권6호
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• pp.509-518
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• 2016

본 연구는 1985년부터 2015년까지 지속기간에 따른 청미천 유역의 가뭄을 분석하였다. 가뭄의 정량적 평가를 위해 기상학적 가뭄지수와 수문학적 가뭄지수를 사용하였다. 기상학적 가뭄지수로는 강수량을 변수로 하는 SPI(Standarized Precipitation Index)와 강수량과 증발산량을 변수로 하는 SPEI(Standarized Precipitation Evapotranspiration Index)를 사용하였다. SWAT 모형의 모의를 통해 도출된 결과를 바탕으로 농업학적 가뭄지수인 PDSI(Palmer Drought Severity Index)와 수문학적 가뭄지수인 SDI(Streamflow Drought Index)를 적용하였다. 산정 결과, 극한 및 평균 가뭄의 평균에서 2015년과 2014년이 가장 가뭄에 취약함이 확인되었다. 빈도분석에 따른 가뭄의 변동성은 서로 다른 형태를 보였다. 또한 상관분석에서 극한 가뭄 및 평균 가뭄은 PDSI를 제외한 SPI, SPEI, SDI 가뭄지수간에는 높은 상관관계가 확인되었다. 하지만 각 가뭄지수는 서로 다른 극한가뭄의 시기 및 강도를 보였다. 따라서 가뭄분석시 다양한 특성을 지닌 가뭄지수를 활용하는 것이 필요하다.

• 대한원격탐사학회지
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• 제36권4호
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• pp.627-635
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• 2020

With the increasing severity of climate change, intense torrential rains are occurring more frequently globally. Flooding due to torrential rain not only causes substantial damage directly, but also via secondary events such as landslides. Therefore, accurate and prompt flood detection is required. Because it is difficult to directly access flooded areas, previous studies have largely used satellite images. Traditionally, water indices such asthe normalized difference water index (NDWI) and modified normalized difference water index (MNDWI) which are based on different optical bands acquired by satellites, are used to detect floods. In addition, as flooding likelihood is greatly influenced by the weather, synthetic aperture radar (SAR) images have also been used, because these are less influenced by weather conditions. In this study, we compared flood areas calculated from SAR images and water indices derived from Landsat-8 images, where the images were acquired at similar times. The flooded area was calculated from Landsat-8 and Sentinel-1 images taken between the end of May and August 2019 at Lijiazhou Island, China, which is located in the Changjiang (Yangtze) River basin and experiences annual floods. As a result, the flooded area calculated using the MNDWI was approximately 21% larger on average than that calculated using the NDWI. In a comparison of flood areas calculated using water indices and SAR intensity images, the flood areas calculated using SAR images tended to be smaller, regardless of the order in which the images were acquired. Because the images were acquired by the two satellites on different dates, we could not directly compare the accuracy of the water-index and SAR data. Nevertheless, this study demonstrates that floods can be detected using both optical and SAR satellite data.

• 한국수자원학회논문집
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• 제39권3호
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• pp.199-214
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• 2006

가뭄기간의 효율적인 저수지 운영은 가뭄계획에서 중요한 요소이다. 본 연구에서는 가뭄기간에 저수지의 용수공급능력을 모니터링 할 수 있는 새로운 가뭄지수로서 물공급능력지수(Water Supply Capacity Index, WSCI)를 개발하였다. WSCI는 극심한 기상조건하에서 각 저수지가 수요량에 대해 어느 정도 기간 용수를 공급할 수 있는가를 평가할 수 있는 정량적 지표이다. WSCI는 가뭄기간의 저수지 운영을 위한 의사결정에 대한 유용한 정보를 제공하고, 저수지에서 용수를 공급받는 지역의 가뭄단계 설정에 활용될 수 있다. 표준화된 WSCI와 기존에 널리 이용되고 있는 PDSI, SPI, SWSI와 비교 분석함으로써 WSCI의 유용성을 확인하였다.

• Journal of Information Processing Systems
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• 제16권4호
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• pp.784-794
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• 2020

In order to effectively evaluate the urban water security, the study investigates a novel system to assess factors that impact urban water security and builds an urban water poverty evaluation index system. Based on the contribution rates of Resource, Access, Capacity, Use, and Environment, the study adopts the Water Poverty Index (WPI) model to evaluate the water poverty levels of 14 cities in Gansu during 2011-2018 and uses the least variance method to evaluate water poverty space drive types. The case study results show that the water poverty space drive types of 14 cites fall into four categories. The first category is the dual factor dominant type driven by environment and resources, which includes Lanzhou, Qingyang, Jiuquan, and Jiayuguan. The second category is the three-factor dominant type driven by Access, Use, and Capability, which includes Longnan, Linxia, and Gannan. The third category is the four-factor dominant type driven by Resource, Access, Capability, and Environment, which includes Jinchang, Pingliang, Wuwei, Baiyin, and Zhangye. The fourth category is the five-factor dominant type, which includes Tianshui and Dingxi. The driven types impacting the urban water security factors reflected by the WPI and its model are clear and accurate. The divisions of the urban water security level supply a reliable theoretical and numerical basis for an urban water security early warning mechanism.