• Journal of The Korean Society of Agricultural Engineers
• /
• v.59 no.4
• /
• pp.1-15
• /
• 2017

Eutrophication of surface waters is of concern worldwide, because it can result in many undesirable water-quality and ecological problems, such as hypoxic 'dead' zones and harmful algal blooms, both associated with considerable economic costs. In this study, we used LSM (Land Surface Model) to simulate nitrogen in five major rivers in the Southern Korean Peninsula. The main objective of this research was to enhance nitrogen data for input of LM3V model in South Korea. Input data for nitrogen fluxes were categorized into three sections including agriculture fertilizer, livestock manure, atmosphere deposition, biological fixation, and sewage pollutants were used as the nitrogen input. For using LM3V model, the nitrogen input data were regenerated by considering states of agriculture and industry in South Korea at a $1/8^{\circ}$ resolution. Then, we simulated stream/river flows and N loads throughout the entire drainage networks in South Korea at a $1/8^{\circ}$ resolution. By using the same parameters for the entire country ($100,210km^2$), composed of 5 river basins with varying climate and land use, the model simulates spatial (11 sites) and temporal (1999~2010) patterns of flows and nitrate-N loads are resonable by comparing observed flow and nitrate-N loads. The r (Pearson's linear correlation) for water temperature, flow and nitrate-N at river were 080~0.93, 0.62~0.92 and 0.5~0.9 respectively. Based on enhanced N input data and model results, we find that LM3V model as land surface model can be applied in South Korea with interaction of atmosphere and land conditions.

• Journal of Korean Society of Disaster and Security
• /
• v.12 no.4
• /
• pp.53-61
• /
• 2019

Occurrences of debris flow are a serious danger to roads and residential located in mountainous areas and cause a lot of property loss. In this study, two basins were selected and spatial data were constructed to simulate the occurred debris flow from mountainous areas. The first basin was to use the Terrestrial LiDAR to scan the debris flow occurrence section and to build terrain data. For the second basin, use drones the sediment in the basin was photographed and DSM (Digital surface model) was generated. And to analyze the effect of the occurrence of debris flow on downstream side, FLO-2D, two-dimensional commercial model, was used to simulate the flow region of the debris flow. And it was compared with the sedimentation area of terrestrial LiDAR and drone measurement data.

• Journal of Korean Society on Water Environment
• /
• v.34 no.3
• /
• pp.308-315
• /
• 2018

SWMM-LID was calibrated with flow monitoring data in LHI to evaluate runoff after LID application. The flow rate in the B basin was estimated to be 0.94 and 6.15 for O/S and $D_v$, respectively. In the A and C basins, the difference between the observed and simulated data was greater than in the B basin. As a result of runoff reduction efficiency by the application of LID facilities, the change of infiltration increased from 34.6 % to 45.8 % in the entire watershed, and the runoff decreased from 58.8 % to 46.3 %. In the runoff reduction of each LID facility, rain garden E showed the highest effect with 99.9 % and bioretention B showed the lowest effect with 27.5 %. In order to evaluate the efficiency of each LID facility, a comparison is made between the pore volume (V) of the LID and the catchment area (A). The runoff showed a runoff reduction effect of about 70 % above the 0.1 volume/area (V/A) value. As a result of examining the runoff reduction with LID facilities by the LID module of SWMM, a reasonable design is possible by reflecting the appropriate LID volume to drainage area.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.11 no.4
• /
• pp.349-354
• /
• 2017

In this study, we proposed a design guideline of height-adjustable wash basin which is an assistive product for personal hygiene for persons with disability. We performed biomechanical assessments using both of conventional and prototype height adjustable wash basin. Total five elderly subjects (all male, age $68.6{\pm}4.3yrs.$, height $169.8{\pm}5.7cm$, weight $70{\pm}7.7kg$) participated for the assessment test. Each joint angles were measured by using a 3D motion capture system when subjects use wash basins, and the lumbar moment of each subjects was estimated based on a human body model. From the assessment results, a design guideline which has the range of the height from 652[mm] to 1162[mm] was proposed. Then additional assessment tests with five healthy subjects ($25.8{\pm}1.8yrs.$, $175.5{\pm}5.8cm$, $74{\pm}15.7kg$) were performed in order to verify effectiveness of the design guideline. The results showed a height-adjustable wash basin applied the proposed design guideline was effective to reduce the lumbar moment.

• Spatial Information Research
• /
• v.17 no.3
• /
• pp.389-395
• /
• 2009

In spite of many numerical analysis of debris flow, a little information has been found out. In this paper the watershed is divided to apply rainfall runoff and to estimate debris flow integrating flow and soil article. We use the contour data to extract spatially distributed topographical information like stream channels and networks of sub-basins. A Quasi Digital Elevation Model (Q-DEM) is developed, integrated, and adopted to estimate runoff based on marked one. As a results, it has been found out that the debris flow was close to observed flow hydrograph. Because debris flow is finished in 30 second, it is important that we have to prepare its prior countermeasure to minimize the damage of debris flow. The GIS-linked model will provide effective information to plan river works for debris flow.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2002.10a
• /
• pp.100-107
• /
• 2002

This study investigates the seasonal variation and spatial distribution characteristics of pollutant load, as executing the quantity valuation of pollutant load inflowing into Yeong-Il bay from on-land including the Hyeong-san river. Annual total pollutant generating rate from Yeong-Il bay region are 202ton to BOD, 620ton to SS, 42ton to T-N, 16ton to T-P respectively, if expressly point out, pollutant generating rate from the Hyeong-san river is the greatest, which BOD ratio is 78.2%, SS 88.5%, T-N 62.5%, T-P 73.1%. As calculating Tank model with input value of daily precipitation and evaporation of 2001 year in drainage basin of the Hyeong-san river, Estimated result of the annual total river discharge effluencing from this river is $830{\times}106m^3$. As result to estimating annual total effluence rate outflowing at the rivers from each drainage basins, annual total inflow pollutant rate are BOD 10,633ton, SS 19,302ton, T-N 15,369ton, T-P 305ton. The III basin which is population congestion region of the Pohang-city drain away a good many pollutant load than the V basin including the Neang-Chun with wide drainage area. Especially, a great many T-N than T-P inflow into Yeong-Il bay. The accumulation of pollutant load effluenced from on-land will happen on at the inner coast region of Yeong-Il bay, finally we would make a prediction that the water quality will take a bad turn.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2022.05a
• /
• pp.466-466
• /
• 2022

2018년 물관리 일원화를 위한 정부조직법 개정으로 기존 국토교통부의 「수자원의 조사·계획 및 관리에 관한 법률」 등의 사무가 환경부로 이관되었다. 과거 부처별로 나누어진 물 관리 체계에 따라 부처간 업무중복, 과잉투자 등 수량과 수질에 대한 분리된 관리체계의 한계점으로 유역 상류에 설치된 댐의 경우 저류된 댐 용수의 수질악화의 문제가 발생하였다. 또한, 물관리 일원화 이후, 「제2차 물환경관리 기본계획」에서는 2025년까지 주요 상수원 수질을 좋음(I)등급 달성을 목표로 제시하였고, 이와 연계하여 평가지표 등에 설정한 댐 수질목표를 2025년까지 매우좋음(Ia) 등급 달성을 위해서는 댐 상류 주요 오염원에 대한 과학적 분석이 필요하며 이에 대한 관리대책 마련이 시급한 상황이다. 본 연구의 공간적 범위인 사연댐은 울산공업지구의 공업용수 확보를 위해 1965년 준공되어 울산 일원에 100,000m³/일 이상의 공업용수를 공급하는 수원시설이며, 대곡댐은 기존 울산지역에 공업용수로 사용하던 사연댐의 물을 생활용수로 전환하고, 대곡·사역댐의 연계운영을 통해 연간 66백만의 생활용수를 공급하기 위한 수원시설이다. 수질 목표기준의 경우 대곡댐은 좋음(Ib), 사연댐은 매우좋음(Ia)로 설정되어 있으나, 2015~2019년까지의 TOC, T-P의 평균 달성률을 살펴보면 대곡댐은 TOC 45.8%, T-P 27.1%의 목표수질 달성률을 나타내었고, 사연댐은 TOC 및 T-P 모두 0%로 목표수질을 달성하지 못한 것으로 조사되었다. 본 연구에서는 대곡·사연댐 상류 유역을 대상으로 유역의 특성 및 오염원 발생 특성을 파악하고, 이에 따른 물환경관리 종합대책을 수립하기 위하여 1) 유역 물환경 기초자료 조사와, 2) 모니터링을 통한 댐유역 오염 원인분석을 수행하였다. 그 결과를 바탕으로 소유역별 오염부하량을 분석하고 개선대책(안)을 도출하였다. 이 때, 개선대책의 효과를 분석하기 위해서 유역 모형(HSPF)과 호소수질(AEM3D) 모형을 활용하여 수질모델 구축 및 보정을 수행하였고, 개선 대책(안)에 대한 목표수질 달성여부를 파악하였다. 최종적으로 대곡·사연댐 유역의 호소수질 변화를 파악하고 댐 유역 특성을 고려한 맞춤형 물환경관리 종합대책을 제시하였다.

• Economic and Environmental Geology
• /
• v.39 no.2 s.177
• /
• pp.129-149
• /
• 2006

Previously published stratigraphic, sedimentologic, paleontologic, paleomagnetic and geophysical data are reviewed to make an understanding on the tectonic evolution of the Cretaceous Gyeongsang (Kyongsang) basin, southeast Korea. A stratigraphic framework and a tectonic model on the formation and deformation of the Gyeongsang Basin are newly proposed on the basis of integration these data with magmatism and mineralization ages in the basin. A newly proposed stratigraphic framework indicates that strata in the basin can be subdivided into five distinct stratigraphic units that represent pre-rifting, syn-rifting, inversion I, II, and III stages. The Gyeongsang Basin was formed initially as a pre-rifting stage due to north-south extension in the Late Jurassic prior to a syn-riftins stage that resulted from east-west extension during the Early Cretaceous. In the Late Cretaceous, the basin was deformed by three-staged sequential deformation of north-south, northwest-southeast, and east-west compressions. The tectonic history of the basin has been largely controlled by the change of motion of the Izanagi Plate from north to northwest during the Cretaceous. In the early Cretaceous, the Izanagi Plate began to subduct northward beneath the Eurasian Plate and caused the left-lateral strike-slip fault systems in the southern part of the peninsula. The left-lateral wrenching of these fault systems was causally linked to development of pull-apart basins, such as the Gyeongsang Basin in the southeastern part of the peninsula. However, northwestward movement of the Izanagi Plate during the Late Cretaceous probably led to the extensive volcanism as well as sequential deformations in the basin. The stratigraphic and tectonic model, which is newly proposed as a result of this study, may be expected to enhancing the efficiency for exploration and exploitation of useful mineral resources in the basin as well as establishing geologic history in the Cretaceous Gyeongsang Basin. Together with the spatial and temporal correlation of the Cretaceous basins in adjacent areas, this stratigraphic and tectonic model provides a new geologic paradigm to delineate the sophisticated tectonic history of East Asia turing the Cretaceous.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.17 no.3
• /
• pp.104-115
• /
• 2014

A levee is defined as an man-made structure protecting the areas from temporary flooding. This paper suggests a methodology for establishing the levee GIS database using the airborne topographic LiDAR(Light Detection and Ranging) data taken in the Nakdong river basins and the WAMIS(WAter Management Information System) information. First, the National Levee Database(NLD) established by the USACE(United States Army Corps Engineers) and the levee information tables established by the WAMIS are compared and analyzed. For extracting the levee information from the LiDAR data, the DSM(Digital Surface Model) is generated from the LiDAR point clouds by using the interpolation method. Then, the slope map is generated by calculating the maximum rates of elevation difference between each pixel of the DSM and its neighboring pixels. The slope classification method is employed to extract the levee component polygons such as the levee crown polygons and the levee slope polygons from the slope map. Then, the levee information database is established by integrating the attributes extracted from the identified levee crown and slope polygons with the information provided by the WAMIS. Finally, this paper discusses the advantages and limitations of the levee GIS database established by only using the LiDAR data and suggests a future work for improving the quality of the database.

• Journal of Korea Water Resources Association
• /
• v.51 no.7
• /
• pp.617-627
• /
• 2018

In this study, CMIP5 GCMs rainfall data (2011~2099) based on RCP scenarios were used to analyze the extreme drought evaluation for the future period. For prospective drought assessment, historical observations were used based on the Automated Surface Observing System (ASOS) data (1976~2010) of the Korea Meteorological Administration. Through the analysis of various indicators, such as average annual rainfall, rainy days, drought spell, and average drought severity was carried out for the drought evaluation of the five major river basins (Han river, Nakdong river, Geum river, Sumjin river, and Youngsan river) over the Korean peninsula. The GCMs that predicted the most severe future droughts are CMCC-CMS, IPSL-CM5A-LR and IPSL-CM5A-MR. Moderate future droughts were predicted from HadGEM2-CC, CMCC-CM and HadGEM2-ES. GCMs with relatively weak future drought forecasts were selected as CESM1-CAM5, MIROC-ESM-CHEM and CanESM2. The results of this study might be used as a fundamental data to choose a reasonable climate change scenario in future extreme drought evaluation.