• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.1
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• pp.25-43
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• 2016

This research was completed to provide fundamental data regarding the guidelines to installing and managing utility facilities & structures in wetland protected area to advance the functions and sustainable use of ecology services by preserving the ecology within wetland protected area. There were 5 on-site researching areas that were used as the main subject with these areas chosen and considered from 21 inland wetlands that have been designated and are being managed from the Ministry of Environment and by their designated dates as a wetland protected area. The utility facilities in these wetland areas were categorized by their types and a detailed on-site investigation was proceeded with investigation items chosen whereas these facilities are working by their roles from their location, size, used materials, types, information contents and etc., The results showed that regarding informational structures, several locations of information boards were distanced from the main exploring routes which did not consider the visitor's eye level which had their readability dropped and by sunlight, time lapse and water penetration, many information boards were damaged or corrupted so that it was hard to confirm the information noticed or understanding an image. Insufficient observation and educational structures were installed that considered the ecological characteristics of wild animals and their living conditions. Regarding convenience facilities, there were parking lots that were installed on the fore-land and to decrease non-point solution sources, some parking lots needed to be located in protected lowlands while some facilities' shape and colors did not harmonize with their natural surroundings, creating a sense of awareness, which will need some more consideration. As for safety facilities, they were very insufficient compared to other facilities. This means that additional safety structures are needed so that related personnel can be aware of where a visitor is located when an accident occurs. Protectional facilities strongly needed new structures and a management system to cut off entrances and do surveillance so that visitors do not go into areas outside of the managed areas and bring damages to restricted locations. Research labs needed to expand the use of automatic weather systems and water gauge equipments to build fundamental data regarding floodgates that are intimated to the forming of wetlands. Sensor cameras and other types of monitoring systems are needed to monitor the majority types of animals living in the wetlands as well.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.3
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• pp.193-210
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• 2013

This study aims to assess the slope stability variation of Jeollabuk-do drainage areas by RCM model outputs based on A1B climate change scenario and infinite slope stability model based on the specific catchment area concept. For this objective, we downscaled RCM data in time and space: from watershed scale to rain gauge scale in space and from monthly data to daily data in time and also developed the GIS-based infinite slope stability model based on the concept of specific catchment area to calculate spatially-distributed wetness index. For model parameterization, topographic, geologic, forestry digital map were used and model parameters were set up in format of grid cells($90m{\times}90m$). Finally, we applied the future daily rainfall data to the infinite slope stability model and then assess slope stability variation under the climate change scenario. This research consists of two papers: the first paper focuses on the methodologies of climate change scenario preparation and infinite slope stability model development.

• Journal of Korea Water Resources Association
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• v.47 no.2
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• pp.119-133
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• 2014

The study adopted extended Kalman filter technique in an effort to predict Z-R relationship parameter as a stable value in real-time. Toward this end, a parameter estimation model was established based on extended Kalman filter in consideration of non-linearity of Z-R relationship. A state-space model was established based on a study that was conducted by Adamowski and Muir (1989). Two parameters of Z-R relationship were set as state variables of the state-space model. As a result, a stable model where a divergence of Kalman gain and state variables are not generated was established. It is noteworthy that overestimated or underestimated parameters based on a conventional method were filtered and removed. As application of inappropriate parameters might cause physically unrealistic rain rate estimation, it can be more effective in terms of quantitative precipitation estimation. As a result of estimation on radar rainfall based on parameters predicted with the extended Kalman filter, the mean field bias correction factor turned out to be around 1.0 indicating that there was a minor difference from the gauge rain rate without the mean field bias correction. In addition, it turned out that it was possible to conduct more accurate estimation on radar rainfall compared to the conventional method.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1854-1858
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• 2007

수자원 분야에서 가장 기본적이면서 중요한 과업 중의 하나는 고품질의 유량측정 자료를 확보하여 신뢰성 있는 수위-유량관계곡선식을 개발하는 것이다. 이는 수공구조물 설계, 친수 하천공간 조성, 친환경적인 하천의 설계, 하천 관리수량 산정, 홍수 예 경보 운영 등에 기본적인 자료를 제공하게 된다. 신뢰성 있는 곡선식은 계측장비의 개량과 유량관측 기준의 강화 등을 통하여 축적된 양질의 유량측정 자료로부터 개발될 수 있으며, 또한 수위관측소 지점의 하도특성과 통제구조물의 특성 등을 고려하는 것도 곡선식의 신뢰도를 높일 수 있다. 본 연구는 통제단면의 가장 낮은 부분의 수위로 정의되는 흐름이 0인 수위인 GZF(Gauge Height of Zero Flow) 평가에 관한 연구이다. 이와 같은 연구를 수행하기 위해서 GZF의 변화에 따라 곡선식의 신뢰도를 분석할 수 있는 시스템을 개발하였으며, 이 시스템은 사용자들이 쉽게 이용할 수 있는 엑셀 VBA(Visual Basic for Applications)를 이용하여 개발하였다. GZF 평가 시스템은 입력자료 구축 모듈, 수위관측소 지점의 하도 단면 입력 모듈, GZF 설정 모듈, GZF 평가 모듈의 4개 모듈로 구성되었다. 입력자료 구축 모듈은 기 개발된 곡선식의 GZF 적정성을 파악할 수 있도록 자료를 구축하는 모듈이며, 하도 단면 입력 모듈은 수위관측소 지점의 하상의 변화 유무와 구간분리, 기간분리 등의 필요성을 파악할 수 있도록 구성하였다. GZF 설정 모듈은 GZF의 변화가 곡선식의 신뢰도를 파악할 수 있도록 구성되었다. 마지막으로 GZF 평가 모듈은 기 개발된 곡선식의 GZF와 금회 개발될 곡선식의 GZF를 비교 분석할 수 있도록 구성되었다. 본 연구의 성과는 향후 수위-유량관계곡선식을 개발할 때 GZF 산정의 오류를 감소시켜 앞으로 개발될 곡선식의 신뢰도 향상에 기여를 할 것으로 판단된다.소를 파악해야한다. 7. 부아 유대에 대한 위협요소 확인을 위한 도구개발과 그들에 대한 효과적인 간호전략이 필요 된다. 8. 가족에 있어서 모든 부모행위가 하나의 독립변수로서 연구되어야 하고 부아유대 증진에 관한 연구가 시도되어야겠다. 오늘날 부모들은 임신기간동안 많은 정보에 접하기를 원한다. 산전, 산후의 교육과 지식은 긍정적인 부아 관계를 증진시키고, 이것은 아동의 발달에 크게 기여할 수 있다. 긍정적으로 이러한 관계는 가족단위를 강하게 통합시키게 되므로 건강관리자(Health care workers)들은 애착에 대해 높은 관심을 갖어야 하겠다.2유수지는 BTL사업을 통해 주변공단으로부터의 오폐수를 원천적으로 차단하도록 하였으며 2유수지를 매립하여 지하는 강우시 유출수 저류가 가능한 화물차주차장으로 활용하고 지상은 녹지공간으로 조성하여 공단근로자 및 지역주민을 위한 휴식공간으로 활용될 수 있도록 제안하였다. 본 연구는 남동유수지 환경 개선 사업 실행을 위한 정책 연구로 연구결과를 인천시가 적극 수용하기로 결정함에 따라 인천시의 환경 현안 문제인 남동유수지의 수질개선을 통해 시민의 휴식 및 여가선용 공간으로 활용하기 위한 사업의 기초자료로 활용되며 이미 설계검토가 시작되었다. 본 연구결과는 유수지 및 저수지의 환경개선 사업의 선두적인 성공사례로 국내 타 지역의 유사한 사업에 있어 벤치마킹을 할 수 있는 훌륭한 사례가 될 것이다.요 생산이 증가하자 군신의 변별(辨別)과 사치를 이유로 강력하게 규제하여 백자의 확대와 발전에 걸림돌이 되었다. 둘째, 동기(銅器)의 대체품으로 자기를 만들어 충당해야할 강제성 당위성 상실로 인한 자기수요 감소를 초래하였을 것으로 사료된다. 셋째, 경기도 광주에서 백자관요가 운영되었으므로 지방인 상주지역에도 더 이상 백자를 조달받을 필요가 없이, 일반 지방관아와 서민들의 일상용기 생산으로 전락하여 소규모화 되었을 것이라고 사료

• Spatial Information Research
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• v.20 no.3
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• pp.39-50
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• 2012

The objective of this study is the quantitative analysis of climate change effects by performing several statistical analyses with hydrometeorological data sets for past 30 years in Geum river watershed. Temperature, precipitation, relative humidity data sets were collected from eight observation stations for 37 years(1973~2009) in Geum river watershed. River level data was collected from Gongju and Gyuam gauge stations for 36 years(1973~2008) considering rating curve credibility problems and future long-term runoff modeling. Annual and seasonal year-to-year variation of hydrometeorological components were analyzed by calculating the average, standard deviation, skewness, and coefficient of variation. The results show precipitation has the strongest variability. Run test, Turning point test, and Anderson Exact test were performed to check if there is randomness in the data sets. Temperature and precipitation data have randomness and relative humidity and river level data have regularity. Groundwater level data has both aspects(randomness and regularity). Linear regression and Mann-Kendal test were performed for trend test. Temperature is increasing yearly and seasonally and precipitation is increasing in summer. Relative humidity is obviously decreasing. The results of this study can be used for the evaluation of the effects of climate change on water resources and the establishment of future water resources management technique development plan.

• Journal of Korea Water Resources Association
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• v.36 no.2
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• pp.285-300
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• 2003

An event-based, kinematic, infiltration-excess, and distributed rainfall-runoff model using weather radar and Geographic Information System(GIS) was developed to acknowledge and account lot the spatial variability and uncertainty of several parameters relevant to storm surface runoff and surface flow The developed model is compatible with raster GIS and spatially and temporally varied rainfall data. To calibrate the model, Monte Carlo simulation and a likelihood measure are utilized; allowing for a range of possible system responses from the calibrated model. Using rain gauge adjusted radar-rainfall estimates, the developed model was applied and evaluated to a limited number of historical events for the Ralston Creek and Goldsmith Gulch basins within the Denver Urban Drainage and Flood Control District (UDFCD) that contain mixed land use classifications. While based on a limited number of Monte Carlo simulations and considered flood events, Nash and Sutcliffe efficiency score ranges of -0.19∼0.95 / -0.75∼0.81 were obtained from the calibrated models for the Ralston Creek and Goldsmith Gulch basins, based on a comparison of observed and simulated hydrographs. For the Ralston Creek and Goldsmith Gulch basins, Nash and Sutcliffe efficiency scores of 0.88/0.10, 0.14/0.71, and 0.99/0.95 for runoff volume, peak discharge, and time to peak, respectively, were obtained from the model.

• Journal of Wetlands Research
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• v.17 no.4
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• pp.370-379
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• 2015

In recent, the natural disaster like localized heavy rainfall due to the climate change is increasing. Therefore, it is important issue that the precise observation of rainfall and accurate spatial distribution of the rainfall for fast recovery of damaged region. Thus, researches on the use of the radar rainfall data have been performed. But there is a limitation in the estimation of spatial distribution of rainfall using rain gauge. Accordingly, this study uses the Kriging method which is a spatial interpolation method, to measure the rainfall field in Namgang river dam basin. The purpose of this study is to apply KED(Kriging with External Drift) with OK(Ordinary Kriging) and CK(Co-Kriging), generally used in Korea, to estimate rainfall field and compare each method for evaluate the applicability of each method. As a result of the quantitative assessment, the OK method using the raingauge only has 0.978 of correlation coefficient, 0.915 of slope best-fit line, and 0.957 of $R^2$ and shows an excellent result that MAE, RMSE, MSSE, and MRE are the closest to zero. Then KED and CK are in order of their good results. But the quantitative assessment alone has limitations in the evaluation of the methods for the precise estimation of the spatial distribution of rainfall. Thus, it is considered that there is a need to application of more sophisticated methods which can quantify the spatial distribution and this can be used to compare the similarity of rainfall field.

• Journal of Korea Water Resources Association
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• v.45 no.7
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• pp.729-741
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• 2012

Among the methods of precipitation data acquisition, a rain gauge station has a distinctive advantage of direct measurement of rainfall itself, but multiple stations should be installed in order to obtain areal precipitation data required for hydrological analysis. On the other hand, a rainfall radar may provide areal distribution of rainfall in real time though it is an indirect measurement of radar echoes on rain drops. Rainfall radars have been shown useful especially for forecasting short-term localized torrential storms that may cause catastrophic flash floods. CAPPI (Constant Altitude Plan Position Indicator), which is one of the several types of radar rainfall image data, has been provided on the Internet in real time by Korea Meteorological Administration (KMA). It is one of the most widely available rainfall data in Korea with fairly high level of confidence as it is produced with bias adjustment and quality control procedures by KMA. The objective of this study is to develop an improved way to extract quantitative rainfall data applicable to even very small watersheds from CAPPI using CIVCOM, which is a new image processing method based on a vector-based scheme proposed in this study rather than raster-based schemes proposed by other researchers. This study shows usefulness of CIVCOM through comparison of rainfall data produced by image processing methods including traditional raster-based schemes and a newly proposed vector-based one.

• The Journal of Engineering Geology
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• v.6 no.3
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• pp.155-163
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• 1996

The current ASTM C227-90 is a prescription on the mortar-bar method. This recornrnends that mortar-bars should be made using a mixing ratio by weight of 675 grams aggregate to 300 grams cement, and their initial lengths should be measured in $24{\pm}2$ hours. This method emphasizes that the prepare sample mortar-bars and calculate expansion rates of them. This method requires constant G values (effective gauge lengths) of denominator in the calculation formula, which are fixed either at 10 inches or 250mm. This study, based on experimental approaches, reexamines the suggestions made by those two prescriptions above and important results are summarized in the following. 1. Not only alkali-aggregate reaction but also interaction of interstitial and gel water are responsible for expansion of mortar-bars. This requires partial modification of the current ASTM C227-90. 2. A mixing ratio by volume rather than by weight of aggregate to cement is recommendable for measuring the amount of expansion resulting from alkali-aggregate reaction and from interstitial water. 3. The method of when to measure initial lengths and how to calculate expansion rate suggested by ASThI C227-90 and Cl90-93a should partly be modified for more accurate results.

• Journal of Korea Water Resources Association
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• v.50 no.3
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• pp.155-167
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• 2017

Accurate QPE (Quantitative Precipitation Estimation) and the quality of the rainfall data for hydrological analysis are very important factors. Especially, the quality has a great influence on flood runoff result. It needs to know characteristics of the uncertainties in radar QPE for the reliable flood analysis. The purpose of this study is to present a probabilistic approach which defines the range of possible values or probabilistic distributions rather than a single value to consider the uncertainties in radar QPE and evaluate its applicability by applying it to radar rainfall. This study generated radar rainfall ensemble for the storms by the typhoon 'Sanba' on Namgang dam basin, Korea. It was shown that the rainfall ensemble is able to simulate well the pattern of the rain-gauge rainfall as well as to correct well the overall bias of the radar rainfall. The suggested ensemble technique represented well the uncertainties of radar QPE. As a result, the rainfall ensemble model by a probabilistic approach can provide various rainfall scenarios which is a useful information for a decision making such as flood forecasting and warning.