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2010, Proceedings of the Korea Water Resources Association Conference
Journal of The Korean Society of Agricultural Engineers, 2019
In order to implement practical alternatives to proactively cope with the agricultural drought, the potential vulnerability of irrigation pumping stations to agricultural drought was quantitatively evaluated. Data for the 124 pumping stations which are correlatable to the three proxy variables, i.e. exposure, sensitivity, and adaptive capacity was collected by the Korea Rural Community Corporation, and then standardized considering distribution of each data set. Finally, the vulnerability index was calculated by multiplying the weights determined by the expert survey. The results showed that the vulnerability index ranged from 0.709 to 0.331 and the most vulnerable pumping stations such as Judam, Wongoo and Jinahn were mostly located in Gyeongbuk province likely because of the climatological characteristics with high temperature and low rainfall around this area. In addition, it was found that the adaptive capacity was a dominant factor comparing to exposure or sensitivity proxy variables in contributing to the vulnerability. It is therefore recommended that more practical alternatives should be employed to effectively reduce the vulnerability of an individual pumping station to agricultural drought. Furthermore, the corresponding data related to adaptive capacity should be systematically organized and managed at a field level to design reliable adaptation strategies.
Han'gug nong'gong haghoe nonmunjib, 2012
This paper presents the Multi Criteria Decision Making (MCDM) to evaluate water resources plan for agricultural reservoir. Preference Ranking Organization METHod for Enrichment Evaluations (PROMETHEE) and Analytic Hierarchy Process (AHP) were used to estimate weight and priority of alternatives to find out the most reasonable and efficient way of water resources assessment. The 6 criteria that both decision maker and beneficiary are satisfied have been identified to secure agricultural water resources and then the priority of 10 subcriteria was set. An enhanced PROMETHEE-AHP model was used to perform pairwise comparison and find out the priority of each alternative because the existing decision making model have uncertainty and ambiguity. Comparison analysis of decision making models was carried out to find a way of suitable decision making and validity of PROMETHEE-AHP model was suggested.
Proceedings of the Korea Water Resources Association Conference, 2017
Han'gug nong'gong haghoe nonmunjib, 2015
In this study, we analyzed the trends of water quality along the main stream in Nakdong river basin using the recent data and seasonal Mann-Kendall test. Monthly averaged values of DO, BOD, SS, COD, TN, and TP from 1989 to 2014 for 14 stations (including 2 TMDLs stations) were used in the study. The trend analysis results showed that BOD and TP at most stations has decreasing temporal trend except a few stations while COD and SS showed increasing trend at most stations. Temporal trends in TN at 8 stations were found to be statistically significant and 5 of them showed increasing temporal trend. Temporally averaged BOD, COD, TN and TP were generally increasing as going downstream and the worst water quality were found at Goryeong and Hyunpung station. Overall, water quality of Nakdong river especially in COD, SS, and TN getting worse in time at most stations and as going downstream.
Korean Society of Hazard Mitigation, 2017
This research aims to predict the water level using deep-learning algorithm. To achieve this goal, we applied the TensorFlow, a deep-learning open source library to predict the water level of Okcheon station in the Guem-river. For model training and prediction, two hourly water level data sets of the 3 water level stations (Sutong, Hotan, Songcheon) are prepared: from 2002 to 2013 (training); from 2014 to 2016 (prediction). Even if many of physical data are necessary to understand water cycle system, in particular, model rainfall-runoff process, we used only upstream observed water level information to predict downstream water level using multi-linear regression and Long Short-Term Memory(LSTM) models based on the TensorFlow. The results showed that the weights(or regression coefficients) of multi-linear regression model were very fluctuated due to training trials, then, the predicted high water level were too much underestimated than the observations. On the other hand, the LSTM model predicted the downstream water level very stably regardless of water level height for the study period because sequence length of the LSTM memorize antecedent water level information for model training and updating.
Journal of the Environmental Sciences, 2008
Journal of The Korean Society of Agricultural Engineers, 2007
Daegi, 2016
Eleven Tropical Cyclone (TC) intensity guidance models in the western North Pacific have been validated over 2008~2014 based on various analysis methods according to the lead time of forecast, year, month, intensity, rapid intensity change, track, and geographical area with an additional focus on TCs that influenced the Korean peninsula. From the evaluation using mean absolute error and correlation coefficients for maximum wind speed forecasts up to 72 h, we found that the Hurricane Weather Research and Forecasting model (HWRF) outperforms all others overall although the Global Forecast System (GFS), the Typhoon Ensemble Prediction System of Japan Meteorological Agency (TEPS), and the Korean version of Weather and Weather Research and Forecasting model (KWRF) also shows a good performance in some lead times of forecast. In particular, HWRF shows the highest performance in predicting the intensity of strong TCs above Category 3, which may be attributed to its highest spatial resolution (~3 km). The Navy Operational Global Prediction Model (NOGAPS) and GFS were the most improved model during 2008~2014. For initial intensity error, two Japanese models, Japan Meteorological Agency Global Spectral Model (JGSM) and TEPS, had the smallest error. In track forecast, the European Centre for Medium-Range Weather Forecasts (ECMWF) and recent GFS model outperformed others. The present results has significant implications for providing basic information for operational forecasters as well as developing ensemble or consensus prediction systems.
2019
The damage to farms due to wild animals such as wild boars and elks increases every year, but, in the current system, the catchers from government hunt animals by using guns at night as making an effort to detect wild animals personally by using flashlights. This is very time-inefficient and immediate follow-up action on being damaged is not possible. In this paper, we introduce a system which can detect and recognize the wild animals or the people with high accuracy using thermal imaging camera and infrared camera in company with deep learning technology, so that could kick out or catch the wild animals more quickly than current system.
Journal of Korea Water Resources Association, 2019
The purpose of this study is to analyze the Mekong River streamflow alteration due to climate change. The future climate change scenarios were produced by bias corrections of the data from East Asia RCP 4.5 and 8.5 scenarios, given by HadGEM3-RA. Then, SWAT model was used for discharge simulation of the Kratie, the main point of the Mekong River (watershed area: 646,000 km2 , 88% of the annual average flow rate of the Mekong River). As a result of the climate change analysis, the annual precipitation of the Kratie upper-watershed increase in both scenarios compared to the baseline yearly average precipitation. The monthly precipitation increase is relatively large from June to November. In particular, precipitation fluctuated greatly in the RCP 8.5 rather than RCP 4.5. Monthly average maximum and minimum temperature are predicted to be increased in both scenarios. As well as precipitation, the temperature increase in RCP 8.5 scenarios was found to be more significant than RCP 4.5. I...
Journal of Rainwater Catchment Systems, 2015
Groundwater resources at Dalad, Inner Mongolia were investigated by groundwater metering in 2013 as supplementary investigation during 2002-2006. Since Dalad is located in the middle reach area of the Yellow River basin and classified as arid or semi-arid area with less than 360mm precipitation and more than 2,200mm potential evaporation, the river water is not sufficiently supplied to the area and therefore, irrigation and industrial waters inevitably depend on groundwater resources. As a result of the investigation, groundwater levels at almost of all the observation wells have descended remarkably since 2005 and especially the decreases in the southern part of the objective area are severe by a range of 0.8-5.4m. The groundwater amount in the southern part in 2013 is roughly estimated to be 2.91×10 7 m 3 , which proves a distinct downward trend. According to the autoregressive-like forecasts, including the Holt-Winters method, the unconfined groundwater in the southern part would be unavailable in the middle of 2030's. The groundwater amount of the objective area is also decreasing severely and the increase in irrigation and industrial waters must be its potential reasons, except the decrease in the precipitation during 2005-2013. The change of the groundwater usage and flows might decrease the discharge of the Yellow River through the groundwater seepage and it is not only a water resources problem in this area, but also in the basin scale. Therefore, the groundwater management in this area is a pressing issue and should be done by local government or some water-utilization association against both irrigation water and industry water users. The water resources are inherently including uncertainty, so continuing observation is essential to maintain the water resources at Dalad.
Journal of Wetlands Research, 2013
In this study we estimated the carrying capacity of the southern intertidal zone of Kanghwa Island to evaluate the habitat quality for Curlews(Far Eastern Curlew Numenius madagascariensis and Eurasian Curlew Numenius arquata). Biomass of the macroinvertebrate(Macrophthalmus japonicus) was estimated by based on the spatial distribution of the sediment grain size using GIS tools. According to our analysis the southern intertidal zone of Kanghwa Island was able to support 11,767 individuals for 153 days in the Spring 2012 and 16,275 individuals for 122 days in the Autumn 2012. The proportion of mean population to the carrying capacity in the Spring and Autumn was 9.4% and 5.9%, respectively. These values are 2.8-6.3% smaller than those of the previous study held in 1993-94. For the conservation of the study area, more research and management is needed. And in further studies, diverse characteristics of the intertidal habitat should be considered in spatial analysis to have a precise estimate of the carrying capacity.
Atmosphere, 2015
A dynamical seasonal prediction system for boreal winter utilizing cryospheric information was developed. Using the Community Atmospheric Model, version3, (CAM3) as a modeling system, newly developed snow depth initialization method and sea ice concentration treatment were implemented to the seasonal prediction system. Daily snow depth analysis field was scaled in order to prevent climate drift problem before initializing model's snow fields and distributed to the model snow-depth layers. To maximize predictability gain from land surface, we applied one-month-long training procedure to the prediction system, which adjusts soil moisture and soil temperature to the imposed snow depth. The sea ice concentration over the Arctic region for prediction period was prescribed with an anomaly-persistent method that considers seasonality of sea ice. Ensemble hindcast experiments starting at 1st of November for the period 1999~2000 were performed and the predictability gain from the imposed cryospheric informations were tested. Large potential predictability gain from the snow information was obtained over large part of high-latitude and of mid-latitude land as a result of strengthened land-atmosphere interaction in the modeling system. Large-scale atmospheric circulation responses associated with the sea ice concentration anomalies were main contributor to the predictability gain.
As a step toward accurate prediction of droplet impingement and ice accretion on aircraft, an Eulerian-based droplet impingement and ice accretion code for air flows around an airfoil containing water droplets is developed. A CFD solver based on the finite volume method was also developed to solve the clean airflow. The finite-volume-based approach for simulating droplet impingement on an airfoil was employed owing to its compatibility with the CFD solver and robustness. For ice accretion module, a simple model based on the control volume is combined with the droplet impingement module that provides the collection efficiency. To validate the present code, it is compared with NASA Glenn IRT (Icing Research Tunnel) experimental data and other well-known icing codes such as LEWICE and FENSAP-ICE. It is shown that the collection efficiency and shape of ice accretion are in good agreement with previous experimental and simulation results.
Journal of the Korea Organic Resource Recycling Association, 2015
Integration of crop-livestock farming has been a problem-solving mode for abatement of environmental pollution and recovery of resources in recent years. The objectives of this study were 1) to suggest the customized integration of crop-livestock farming model reflecting the regional characteristics through in-depth analysis of case study and 2) to analyze the livestock nutrients flow in terms of three primary elements as nitrogen(N), phosphorous(P), and potassium(K). The personal interview and survey were carried out in 2012 for a total of 161 farms from four different regions(NS, NW, JJ, YC) in South Korea. The mass balance analysis was used to suggest and evaluate the models for two sites(JJ and YC). The results showed that NS and NW sites produced relatively more livestock manure than the sites of YC and JJ because of the regional differences in livestock numbers and urbanization. The models were suggested for the site JJ and site YC, and 'two track model(energy and resource recovery)' and 'dispersal type model' were assigned respectively. For the nutrient flows, the releasing P and K with new models had increased up to 7%, while N release had decreased down to 15% in both YC and JJ sites compared to the present treatment system. Estimated value showed that there was oversupply of N (719 ton/yr) and P 2 O 5 (1,269 ton/yr) in YC and deficiency of N (671 ton/yr) and excessive P 2 O 5 (32 ton/yr) in JJ respectively. Therefore, P runoff has to be considered an eutrophication occurs in rural small stream when an integration of crop-livestock farm system is applied into both sites.
The Journal of the Korea Contents Association, 2011
A wetting and drying(WAD) scheme was introduced in KU-RLMS which is a two-dimensional depth-averaged unsteady model, and applicability tests for wetting and drying were performed in this study. WAD scheme in the model uses a mathematically less elegant but numerically easier method to test for dry or wet cells at each time step, then to apply blocking conditions for fluxes at cells' interfaces. WAD scheme introduced in the model was verified against an analytical solution in a frictionless parabolic basin. It was found that there occurs a little phase difference between analytical and numerical solution and little decrease of amplitude of numerical result. I used three test channels having a linear sloping bottom topography, a stepwise bottom topography, and a stepwise, a bumpy and bowl-shaped bottom topography. It could be found that numerical simulation results in test channels have similar shapes of Balzano and Oey[15].
2008
요 지 지난 수십 년 동안 아시아태평양 지역 각국은 수자원 접근성 및 인프라의 확충을 포함한 물관리의 다 , 양한 측면에서 현저히 발전하였다고 평가되고 있다 그러나 급속한 인구 증가 및 경제 성장 도시화 기존 수 . , , 자원의 고갈 등은 아태 지역의 물 수요가 여전히 충족시키지 못하는 원인이다 또한 기후변화로 인한 환경적 . 변화를 고려하여 모든 수자원정책의 입안 및 계획이 이루어져야 한다 경제적 성장률은 전반적으로 높았지만 . 빈곤 문제는 역시 도시나 농촌을 구분할 것 없이 만성적인 문제로 남아 있으며 아태 지역 개도국 인구의 , 가 영양실조 상태이며 년까지 그 수를 반감하자는 밀레니엄 개발목표 16% , 2015 (Millenium Development 달성은 아직 갈 길이 멀다 또한 아태 지역은 물 관련 재해에 대해 전 세계에서 가장 취약한 Goals, MDGs) . 지역이며 그로 인한 지속가능한 발전이 지체되고 있다 년부터 년까지 물 관련 재해로 인한 전 세계 . 196
Journal of KIISE, 2019
Recently, there has been an increase in P2P lending users, a product that supports investments through lending among individuals using online platforms. However, since P2P lending's investors have to take financial risks, the investors may fail to investment due to the close of investment while they considering whether to invest or not. This paper predicts how long an investment product will take from a certain point to the close in order to provide deadline information for P2P loan investment products. To predicts the investment deadline, we have transforms into Timeseries data and Step data based on investment information on actual P2P products. The regression, classification, and time series prediction model were generated using machine learning algorithm. The results of the performance evaluation showed that in the Timeseries data-based model, the Multi-layer Perceptron regression model and the classification model showed the highest performance at 0.725 and 0.703 respectively. The Step data-based model was also the highest with the Multi-layer Perceptron regression model and the classification model at 0.782 and 0.651 respectively.
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