• Journal of Korea Water Resources Association
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• v.31 no.6
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• pp.675-684
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• 1998

This paper presents the empirical formulas for determining the design-width for medium rivers in the Han river basin. The design flood, the watershed ares, and the channel slope of 216 medium rivers in the Han river basin are collected. the design width formulas are then determined by 1) the least squares (LS) method, 2)the least median squares (LMS) method, and 3) the reweighted least squares method based on the LMS (RLS). The six types of formulas are considered to determine the acceptable type for medium streams in the Han river basin. The root mean squared errors (RMSE), the absolute mean (AME) errors, and the mean errors (ME) are computed to test the formulas derived by three regression methods. It si found that the equation related stream width to the watershed area and the channel slope is acceptable for determining the design width for medium streams in the Han river basin. It is expected that the equations proposed by this study be used an index for determining the design-width for medium streams in the Han river basin.

• Journal of Korea Water Resources Association
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• v.38 no.10 s.159
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• pp.895-906
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• 2005

The diversity of observed hydrologic data and the development of geographic information system leads significant progress for developing distributed runoff models in the world. One of the typical examples is TOPMODEL, but the spatial coverage of its application Is limited on small headwater basins. The purpose of this study attempts to overcome its limitation and consequently develops a semi-distributed TOPMODEL. The developed model is composed of two components: a watershed runoff component for a lumped representation of hydrologic runoff process on the catchment scale and a kinematic wave type hydraulic channel routing component lot routing the catchment outflows. The application basin is the $2,703km^2$ upper Soyang dam site and several daily and hourly events are selected for model calibrations and verifications. The model parameters are estimated on 1990 daily event. The model performance on correlation coefficient between observed and computed flows are above 0.90 for the verification events. It is concluded that the developed model in this study can be used for flood analysis in large drainage basins.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.6
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• pp.19-30
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• 2013

This study is to evaluate the use of dual-polarization radar data for storm runoff modeling in Namgang dam (2,293 $km^2$) watershed using KIMSTORM (Grid-based KIneMatic wave STOrm Runoff Model). The Bisl dual-polarization radar data for 3 typhoons (Khanun, Bolaven, Sanba) and 1 heavy rain event in 2012 were obtained from Han River Flood Control Office. Even the radar data were overall less than the ground data in areal average, the spatio-temporal pattern between the two data was good showing the coefficient of determination ($R^2$) and bias with 0.97 and 0.84 respectively. For the case of heavy rain, the radar data caught the rain passing through the ground stations. The KIMSTORM was set to $500{\times}500$ m resolution and a total of 21,372 cells (156 rows${\times}$137 columns) for the watershed. Using 28 ground rainfall data, the model was calibrated using discharge data at 5 stations with $R^2$, Nash and Sutcliffe Model Efficiency (ME) and Volume Conservation Index (VCI) with 0.85, 0.78 and 1.09 respectively. The calibration results by radar rainfall showed $R^2$, ME and VCI were 0.85, 0.79, and 1.04 respectively. The VCI by radar data was enhanced by 5 %.

• Korean Journal of Community Nutrition
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• v.7 no.2
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• pp.219-231
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• 2002

The purpose of this study was to collect basic data on the prevention of and education about diabetes mellitus for the nutritional management of a diabetes mellitus risk group. The study which took place in Kangbukgu, Seoul, involved a diabetes mellitus risk group (DMR $\geq$ 110 mg/dL, 61), of males and females, aged 36 to 68 years, and a group of healthy people as a control group ( < 110 mg/dL, 183), using luting blood sugar (FBS) levels. The proportion of people in the abnormal range was higher in the DMR than that of control group for total cholesterol, high-density lipoproteins-cholesterol (HDL-C), total protein, glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT) and creatinine. Particularly with respect to serum protein the proportion in the DMR in abnormal range (p < 0.05) was significantly higher than that of the control group. The proportion in the DMR with a family history of disease was significantly higher than that of the control group (p < 0.01). Using body mass index (BMI), waist-hip ratio (WHR) and relative body weight (RBW), the obesity indices in the DMR was higher than that of the control group. Comparing the DMR and the control group with respect to dietary habits, it seems that the DMR had more undesirable dietary habits than the control group. When the intake of each nutrient for the DMR and the control group was compared to the Korean recommended dietary allowances (RDA), the proportion of excess intake and deficient intake in the DMR was higher than that of the control group. The DMR showed a greater undesirable dietary intake pattern as compared to that of the control group, based on the RDA. With respect to the dietary diversity score (DDS) and the mean adequacy ratio (MAR) for quality estimation of the overall flood intake, the DMR showed a feater undesirable pattern than the control group. According to the above results, the DMR tended to have more undesirable eating habits when compared to the control group. Therefore, to provide a more efficient nutritional education program for the DMR we must conduct lurker studies on eating habits, so as to provide systematic nutritional management based on theme differences between the DMR and the control group.

• Journal of the Korean Geotechnical Society
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• v.34 no.6
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• pp.25-36
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• 2018

Soil liquefaction is one of the types of major seismic damage. Soil liquefaction is a phenomenon that can cause enormous human and economic damages, and it must be examined before designing geotechnical structures. In this study, we proposed a practical method of developing a multi-hazard fragility surface for liquefaction of levee considering earthquake magnitude and water level. Limit state for liquefaction of levee was defined by liquefaction potential index (LPI), which is frequently used to assess the liquefaction susceptibility of soils. In order to consider the uncertainty of soil properties, Monte Carlo Simulation based probabilistic analysis was performed. Based on the analysis results, a 3D fragility surface representing the probability of failure by soil liquefaction as a function of the ground motion and water level has been established. The prepared multi-hazard fragility surface can be used to evaluate the safety of levees against liquefaction and to assess the risk in earthquake and flood prone areas.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.12
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• pp.1-9
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• 2008

This paper is about l00[W] discrete LED floodlight lighting system, light color and color temperature to be controlled using the 3[W] RGBA LED, is developed the product with optical, heat dissipation, circuit, luminaire and system design. The result, color temperature is changed corresponding to black body locus from 2,000[K] to 10,000[K] and The Color Rendering Index(C.R.I) is achieved from 71 to 91 by high C.RI. Driving voltage is $90{\sim}250[Vac]$, circuit efficiency is 87[%], P.F is more than 93. moreover the LED lens is designed to achieve narrow, middle, wide beam angle, heat dissipation design is executed to minimize variation of luminous output by the surroundings temperature and to ensure reliability.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.613-613
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• 2015

최근 전 지구적인 온난화로 인한 이상기후에 따라 강수량이 증가하고, 특정지역에만 국한되어 집중적으로 비가 내리는 국지성 집중호우의 발생 빈도가 증가하여 이로 인한 극한 홍수나 강우로 인한 산사태 등의 재해가 반복적으로 발생하고 있다. 홍수는 재산 및 인명에 이르기까지 막대한 피해를 야기한다는 점에서 이를 대비하기 위한 방안이 필수적이므로 국가적인 차원에서 홍수피해를 경감시키기 위한 여러 가지 구조적 또는 비구조적 대책들을 제시하고 있지만, 정확한 기상 변화의 예측이 어렵고 다양한 유발 원인들로부터 비롯된 홍수에 모두 대응할 수 있는 통합 대책 마련이 어려운 실정이다. 즉, 사전예방보다는 피해 복구에만 중점을 두고 있기 때문에 홍수 발생 유역의 지역적인 홍수피해 특성을 반영하지 못할 뿐만 아니라 어느 지역이 상대적으로 홍수피해의 위험성이 높은 지역인지도 파악하기 어렵다. 따라서, 본 연구에서는 도시홍수피해 유형인 내수침수피해와 외수침수피해의 유형에 따라 사례들을 조사하고 관련문헌들로부터 도시 홍수 취약성 평가를 위한 대표적 인자들을 도출하였다. 도출된 인자들을 각각 IPCC의 취약성 평가 프레임에 따라 기후노출, 민감도 그리고 적응능력으로 구분하고 도시 상습침수지역인 도림천 유역을 시범 지역으로 하여 도시홍수 취약성 평가를 위한 지수를 개발하고자 한다. 본 연구를 통하여 향후 도시홍수피해의 잠재적 위험성이 높을 것으로 판단되는 유역에 대한 활용방안을 제시하고 유역의 특성 및 중요도에 따른 치수사업의 우선순위를 결정하는 등 유역의 특성을 반영한 구체적 적응정책의 방향성을 세우는데 기초자료로 제공될 수 있으며, 도시홍수로 인한 인명 및 재산의 피해를 최소화 하는 것에 목적이 있다.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.37-37
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• 2015

본 연구는 남강댐 유역($2,293km^2$)을 대상으로 이중편파 레이더 강우자료와 격자기반 분포형 강우-유출 모형인 KIMSTORM(KIneMatic wave STOrm Runoff Model)을 이용하여 홍수추적을 수행하고, 침수실적자료와 비교하여 레이더 강우자료의 효용성을 검토하였다. 2012년 4개의 강우 이벤트(집중호우, 카눈, 볼라벤, 산바)에 대하여 한강홍수통제소로부터 보정된 비슬산 레이더 강우자료를 제공받아 사용하였다. 레이더 강우와 지점 강우를 비교하기 위해 면적평균강우량을 산정하여 분석한 결과, 유출량산정 지점별 면적평균 강우량은 대체적으로 레이더가 지점 강우보다 더 낮은 값으로 예측되었지만, 강우의 패턴은 상당히 일치하는 것으로 나타났으며, 평균 $R^2$는 0.97로 매우 우수하게 분석되었다. 이후 분포형 홍수추적을 위해 KIMSTORM을 이용하였으며, 격자크기 $500{\times}500m$ 해상도의 156행${\times}$137열의 총 21,372개의 셀로 모형을 구축하였다. 분포형 모형의 보정을 위해 지상강우를 적용하여 모형을 보정하고, 보정된 매개변수를 레이더강우에 그대로 적용하여 적용성을 평가하였다. 모형의 보정 결과, $R^2$(coefficient of determination), ME(model efficiency), VCI (volume conservation index)의 평균이 지점강우를 이용한 경우 각각 0.85, 0.78, 1.09%, 레이더 강우를 이용한 경우 각각 0.85, 0.78, 0.96으로 모의유량이 관측유량을 잘 재현하였다. 이후 태풍 산바에 의한 하천범람 침수실적자료의 침수지역(신연, 문대, 신기지구)과 레이더에 의한 침수지역 유출분석 결과를 비교하였다. 침수지역 호우 및 유출의 공간분포를 분석한 결과 레이더 강우가 침수지역 상류유역의 호우와 유출상황을 자세하게 재현하였으며, 침수지역의 침수기간 전 후를 분석한 결과 지점강우 보다 레이더 강우가 실제 첨두유량에 가깝게 우수하게 모의되었다.

• Journal of Korean Society of Disaster and Security
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• v.15 no.3
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• pp.1-14
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• 2022

Recently, the risk of water disasters are increasing due to climate change and the aging of river levees. Existing conventional river embankment inspections have many limitations due to the consumption of a lot of manpower and budget. Thus, it is necessary to establish a new monitoring and forecast/warning method for effective flood response. This study proposes the river levee health monitoring system by analyzing the relationship between river levee deformation and hydrological factors using Sentinel-1. The variance index calculated in this study was classified into 4 grades. And the levees collapse section was judged to be a high vulnerable point in which the variance rapidly increased based on the result of the rapid increase in soil moisture. In the future, it is expected that it will be possible to advance levee maintenance technology and improve national disaster management through the advancement of the existing levee management system and automated monitoring through the forensic method that combines remote technology.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.145-145
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• 2022

Availability of abundant water resources data in developing countries is a great concern that has hindered the adoption of deep learning techniques (DL) for disaster prevention and mitigation. On the contrary, over the last two decades, a sizeable amount of DL publication in disaster management emanated from developed countries with efficient data management systems. To understand the current state of DL adoption for solving water-related disaster management in developing countries, an extensive bibliometric review coupled with a theory-based analysis of related research documents is conducted from 2003 - 2022 using Web of Science, Scopus, VOSviewer software and PRISMA model. Results show that four major disasters - pluvial / fluvial flooding, land subsidence, drought and snow avalanche are the most prevalent. Also, recurrent flash floods and landslides caused by irregular rainfall pattern, abundant freshwater and mountainous terrains made India the only developing country with an impressive DL adoption rate of 50% publication count, thereby setting the pace for other developing countries. Further analysis indicates that economically-disadvantaged countries will experience a delay in DL implementation based on their Human Development Index (HDI) because DL implementation is capital-intensive. COVID-19 among other factors is identified as a driver of DL. Although, the Long Short Term Model (LSTM) model is the most frequently used, but optimal model performance is not limited to a certain model. Each DL model performs based on defined modelling objectives. Furthermore, effect of input data size shows no clear relationship with model performance while final model deployment in solving disaster problems in real-life scenarios is lacking. Therefore, data augmentation and transfer learning are recommended to solve data management problems. Intensive research, training, innovation, deployment using cheap web-based servers, APIs and nature-based solutions are encouraged to enhance disaster preparedness.