• 대한원격탐사학회지
• /
• 제25권3호
• /
• pp.225-231
• /
• 2009

The characteristics of morphological shapes, wave heights, tidal ranges and sediment sizes are observed and compared between intertidal beach and mudflat. The Mohang sand beach, southwest coast of Korea, is located just next to the large mudflat and has tidal range over 5 meters. Wave measurements are conducted at each entrance of the beach and mudflat as well as at the outside waters representing the incident waves to these different coastal environments. The morphological characteristics are also examined including the sediment size and the slope of the bathymetry, For the observation of morphological shapes, camera monitoring technique is used to measure the spatial information of intertidal bathymetry. The water lines moving on the intertidal flat/beach durinq a flood indicate depth contours between low and high water lines. The water lines extracted from the consecutive images are rectified to get the ground coordinates of each depth contours and integrated to provide three dimensional information of intertidal topography. The wave data show that sand beach is in the condition of severer wave forcing but tidal range is almost identical in both environment. The slope of the mudflat is much milder than the sand beach with finer sediment.

• 한국수자원학회논문집
• /
• 제45권10호
• /
• pp.1023-1034
• /
• 2012

선형회귀분석기법은 오랫동안 수공학분야뿐만 아니라 경제학, 통계학 등 여러 분야에서 널리 이용되어 왔다. Fuzzy 회귀분석기법은 자료의 불확실성이 높을 때 이를 정량화하여 회귀분석 모형에 반영할 수 있다. 본 연구에서는 평창강 유역의 임의 지점에서 설계 홍수량을 산정하기 위해 fuzzy 회귀분석모형을 개발하였다. 평창강 유역과 같은 산지하천 유역은 관측소의 부재로 홍수유출해석에 필요한 자료의 습득이 어려운 경우가 많이 있다. 본 연구에서는 지리정보시스템을 이용하여 유역특성인자를 공간적으로 분석하고, 그 결과를 바탕으로 미계측 산지유역에서 설계홍수량을 산정할 수 있는 기법을 검토하였다. Fuzzy 회귀분석기법을 산지하천 유역의 특성을 가지고 있으며 IHP 시험유역 운영을 통하여 비교적 강우와 유량자료가 잘 수집되어 있는 평창강 유역에 적용하였다. 평창강 유역에 대해서 유역특성인자를 이용하여 fuzzy 설계홍수량 산정식을 개발하였고, 유역의 본류를 따라 위치하고 있는 9개의 지점에서 산정된 빈도홍수량과 비교하여 개발된 산정식의 적합성을 검토하였다. Fuzzy 회귀분석을 사용하여 지역회귀분석을 수행한다면 자료 관측에서 발생하는 빈도홍수량의 불확실성을 정량화하고, 불확실성의 전파를 파악할 수 있다.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2002년도 학술발표회 논문집(I)
• /
• pp.43-50
• /
• 2002

Accurate quantitative forecasting of rainfall for basins with a short response time is essential to predict streamflow and flash floods. Previously, neural networks were used to develop a Quantitative Precipitation Forecasting (QPF) model that highly improved forecasting skill at specific locations in Pennsylvania, using both Numerical Weather Prediction (NWP) output and rainfall and radiosonde data. The objective of this study was to improve an existing artificial neural network model and incorporate the evolving structure and frequency of intense weather systems in the mid-Atlantic region of the United States for improved flood forecasting. Besides using radiosonde and rainfall data, the model also used the satellite-derived characteristics of storm systems such as tropical cyclones, mesoscale convective complex systems and convective cloud clusters as input. The convective classification and tracking system (CCATS) was used to identify and quantify storm properties such as life time, area, eccentricity, and track. As in standard expert prediction systems, the fundamental structure of the neural network model was learned from the hydroclimatology of the relationships between weather system, rainfall production and streamflow response in the study area. The new Quantitative Flood Forecasting (QFF) model was applied to predict streamflow peaks with lead-times of 18 and 24 hours over a five year period in 4 watersheds on the leeward side of the Appalachian mountains in the mid-Atlantic region. Threat scores consistently above .6 and close to 0.8 ∼ 0.9 were obtained fur 18 hour lead-time forecasts, and skill scores of at least 4％ and up to 6％ were attained for the 24 hour lead-time forecasts. This work demonstrates that multisensor data cast into an expert information system such as neural networks, if built upon scientific understanding of regional hydrometeorology, can lead to significant gains in the forecast skill of extreme rainfall and associated floods. In particular, this study validates our hypothesis that accurate and extended flood forecast lead-times can be attained by taking into consideration the synoptic evolution of atmospheric conditions extracted from the analysis of large-area remotely sensed imagery While physically-based numerical weather prediction and river routing models cannot accurately depict complex natural non-linear processes, and thus have difficulty in simulating extreme events such as heavy rainfall and floods, data-driven approaches should be viewed as a strong alternative in operational hydrology. This is especially more pertinent at a time when the diversity of sensors in satellites and ground-based operational weather monitoring systems provide large volumes of data on a real-time basis.

• 대한원격탐사학회지
• /
• 제37권5_3호
• /
• pp.1435-1446
• /
• 2021

태풍으로 인한 풍수해는 매년 한반도에 많은 피해를 주고 있다. 재난 발생 시 피해가 최소화 되도록 신속한 의사 결정을 위해서는 예상되는 피해정보와 대피방안 등에 대한 사전 분석이 요구된다. 본 연구에서는 재난단계에 따라 필요한 정보를 제공할 수 있는 분석 모듈을 개발하고자 하였다. 태풍 대비단계에서 활용할 수 있도록 북상 중인 태풍경로와 유사한 과거태풍경로 및 과거피해정보를 확인할 수 있는 기능, 고립 위험 지역을 추출하는 기능, 저수지 붕괴 지역을 추출하는 기능을 개발하였다. 대응 및 복구 초기단계에서 활용할 수 있도록 현 침수심을 고려한 예상침수범위 추출 기능, 인구, 건물, 농지 등에 예상되는 피해정보 분석 기능, 대피정보를 제공하는 기능도 포함하였다. 또한 분석결과 표출을 위해 자동화된 웹 지도 작성 방법을 제시하였다. 분석기능은 파이썬 오픈소스 기반으로 개발하여 모듈화했으며, 웹 표출 기능은 자바스크립트 기반으로 구현하였다. 본 연구에서 개발된 도구들은 풍수해 대비 모니터링과 초기대응 단계에서 신속한 의사결정을 위해 효율적으로 활용될 수 있을 것이다.

• 상하수도학회지
• /
• 제28권6호
• /
• pp.647-655
• /
• 2014

To perform long-term sewer monitoring, It is important to understand the nature of the wastewater flow that occurs at the point on early stage of the monitor and to prevent in advance a problem which may caused. We can infer the flow properties and external factors by analyzing the scatter graph obtained from the measured data flow rate monitoring data since an field external factor affecting the sewage flow is reflected in the flow rate monitoring data. In this study, Selecting the three points having various external factors, and we Inferred the sewer flow characteristics from depth-velocity scatter graph and determined the analysis equation for the dry-weather flow rate data. At the'point 1' expected non-pressure flow, we were able to see the drawdown effect caused by the free fall in the manhole section. At the'point 2', existed weir and sediments, there was backwater effect caused by them, and each of size calculated from the scatter graph analysis were 400 mm and 130 mm. At the'Point 3', there is specific flow pattern that is coming from flood wave propagation generated by the pump station at upstream. In common, adequate equations to explain the dry weather flow data are flume equation and modified manning equation(SS method), and the equations had compatibility for explaining the data because all of $R^2$ values are over 0.95.

• 한국농공학회논문집
• /
• 제58권2호
• /
• pp.31-44
• /
• 2016

This study analyzed pore water pressure, earth pressure and settlement through field monitoring on the project site in which raising embankments are being built through backside extension, and compared the behaviors of seepage analysis, slope stability analysis and stress-strain during flood water levels and rapid drawdown under steady state and transient condition. The variation of pore water pressure showed an increase during the later period in both upstream and downstream slope, with downstream slope more largely increased than upstream slope overall. The variation of earth pressure increased according to the increase of embankment heights, while the change largely showed in the upstream slope, it was slowly increased in the downstream slope. The settlements largely increased until 23 m as embankment heights increased, and showed very little settlement overall. Under a steady state and transient conditions, the seepage quantity per day and leakage quantity per 100 m of embankment against total storage were shown to be stable for piping. The hydraulic gradient at the core before and after raising embankments was greater than the limit hydraulic gradient, showing instability for piping. The safety factor of upstream and downstream slopes were shown to be very large at a steady state, while the upstream slopes greatly decreased at a transit conditions, downstream slopes did not show any significant changes. The horizontal settlements, the maximum shear strain and stress are especially distributed at the connecting portion of the existing reservoir and the new extension of backside. Accordingly, the backside extension method should be designed and reinforced differently from the cases of other types reservoirs.

• 한국방재안전학회논문집
• /
• 제15권3호
• /
• pp.1-14
• /
• 2022

최근 기후변화와 하천 제방의 노후화로 인해 수재해 위험이 가중되고 있으나 기존의 재래적인 하천 제방의 점검은 많은 인력과 예산 소모로 많은 한계점들이 존재하다. 이에 따라 효과적인 홍수 대응을 위해 새로운 모니터링과 예/경보 시스템 구축이 필요한 상황이다. 본 연구는 인공위성(Sentinel-1)을 이용한 하천 제방 변위 산출, 수문학적 요인과의 관계 분석 항목들을 결합한 하천 제방 건강상태 모니터링 방법을 제안한다. 본 연구에서 산정한 변동성 지수를 계산하여 4등급으로 구분하였고, 토양 수분의 급증한 결과를 토대로 제방 붕괴 구간이 변동성이 급증한 취약지점 상태로 판단하였다. 향후에는 원격 기술과 분석 항목들을 결합한 포렌식 기법을 통해 기존 제방관리 시스템의 고도화가 가능할 것으로 기대한다.

• 농업과학연구
• /
• 제39권3호
• /
• pp.451-458
• /
• 2012

Irrigation facilities such as reservoir, sluice, and waterways are managed for preparing flood or drought. It is necessary to efficiently measure water level, flow rate, and related data in national-wide scattered irrigation facilities and to systematically manage data obtained from the facilities. This paper presents a management system for irrigation facilities in order to fast and exact measure their states. The management system consists of mobile device with QR-code function, sensors and gateways, a monitoring system and telecommunication networks. In order to present the benefits of the adoption of the management system against the legacy hand-writing way, this paper presents a economic analysis and its illustrative result.

• 산업기술연구
• /
• 제25권B호
• /
• pp.165-170
• /
• 2005

This paper presents a development of the Data Logger System to transmit the outcome of the waterlevel measuring instrument using the pressure sensor by means of the CDMA network. In or order to set up the real time monitoring the waterlevel measurement system, we have designed the waterlevel sensor, communication terminal and repeater, and data logger. Furthermore, its application for the GIS(Geographical Information System) with management sever system and software solutions have also been developed to minimize the property damages from the flood disaster which occurs every year in the river.

• The Korean Journal of Ecology
• /
• 제27권4호
• /
• pp.211-216
• /
• 2004

The complex ecological researches were made in the broad-leaved forest zone of Central Europe in nature reserves and national parks located on the banks of the river (hydrology, vegetation, soils, unconfined ground waters). The natural conditions of terrestrial ecosystems and natural sites were compared along the course of the rivers. The significant negative influence of low-dammed (low-confined hydrotechnic) construction and small reservoirs on vegetation and soils of floodplain was revealed. On the basis of analysis of mean annual water level and flow trends on the multi-years series (60-100 years) of the hydrometric stations on the rivers under consideration the significant influence of natural long-term variability of watering on vegetation dynamics in the floodplains was revealed.