• 물과 미래
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• 제4권1호
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• pp.51-58
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• 1971

Hydrologic data serve as an input to the water resources system. An adequate analysis of hydrologic data is one of the most important steps in the planning of the water resources development program. The natural hydrologic processes, which produce the hydrologic data, are truely 'stochastic' in the sense that natural hydrologic phenomena change with time in accordance with the law of probability as well as with sequential relationship between their occurrences. Therefore, the stochastic approach to the analysis of hydrologic data has become more popular in recent years than the conventional deterministic or probabilistic approach. This paper reviews the mathematical models which can adequately simulate the stochastic behavior of the hydrologic characteristics of a hydrologic system. The actual application of these models in the analysis of hydrologic records(precipipitation and runoff records in particular) is also presented.

• 한국농공학회논문집
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• 제53권2호
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• pp.9-17
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• 2011

Based on the statistical annual report, there are 17,649 reservoirs are operating for the purpose of agricultural water supply in Korea. 58 % of entire agricultural reservoirs had been constructed before 1948 which indicate the termination of required service life and rest of those reservoirs have also exposed to the dam break risk by extreme flood event caused by current ongoing climate change. To prevent damages from dam failure accident of these risky small size dams, it is necessary to evaluate and manage the structural and hydrological safety of the reservoirs. In this study, a simplified evaluation method for hydrologic safety of dam is suggested by using Rational and Creager formula. Hydrologic safety of small scale dams has evaluated by calculating flood discharge capacity of the spillway and compares the results with design frequency of each reservoir. Applicability and stability of suggested simplified method have examined and reviewd by comparing the results from rainfall-runoff modeling with dam break simulation using HEC-HMS. Application results of developed methodology for three sample reservoirs show that simplified assessment method tends to calculate greater inflow to the reservoirs then HEC-HMS model which lead lowered hydrologic safety of reservoirs. Based on the results of application, it is expected that the developed methodology can be adapted as useful tool for small scale reservoir's hydrologic safety evaluation.

• 한국수자원학회논문집
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• 제45권6호
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• pp.597-606
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• 2012

DEM(Digital Elevation Model) 크기의 변화에 따라 특정 지역에 많은 규격의 수문 데이터가 존재할 수 있기 때문에, 어느 지역, 어느 기상 데이터에도 작동할 수 있는 수문 모형의 개발이 절실히 필요하게 되었다. 이와 같은 필요성을 설명하기 위해서 객체지향(object-oriented)적인 프로그래밍 기술을 적용한 GHISMO(Geographic and Hydrologic Information System Modeling Objects)라는 수문모형(hydrologic model)을 개발하였다. GHISMO의 가장 핵심적인 수문학적 접근방법은 저류-배출(storage-release)과 지표면 유효 강수량을 구하기 위하여 SCS curve number 방법을 사용한 것이다. 이 연구에서 수문모형의 모의실험 결과를 제공할 것이다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2012년도 학술발표회
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• pp.35-35
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• 2012

Most grid-based distributed hydrologic models are complex in terms of data requirements, parameter estimation and computational demand. To address these issues, a simple grid-based hydrologic model is developed in a geographic information system (GIS) environment using storage-release concept. The model is named GIS Storage Release Model (GIS-StoRM). The storage-release concept uses the travel time within each cell to compute howmuch water is stored or released to the watershed outlet at each time step. The travel time within each cell is computed by combining the kinematic wave equation with Manning's equation. The input to GIS-StoRM includes geospatial datasets such as radar rainfall data (NEXRAD), land use and digital elevation model (DEM). The structural framework for GIS-StoRM is developed by exploiting geographic features in GIS as hydrologic modeling objects, which store and process geospatial and temporal information for hydrologic modeling. Hydrologic modeling objects developed in this study handle time series, raster and vector data within GIS to: (i) exchange input-output between modeling objects, (ii) extract parameters from GIS data; and (iii) simulate hydrologic processes. Conceptual and structural framework of GIS StoRM including its application to Pleasant Creek watershed in Indiana will be presented.

• 한국물환경학회지
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• 제36권3호
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• pp.229-244
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• 2020

Hydrologic models, as a useful tool for understanding the hydrologic phenomena in the watershed, have become more complex with the increase of computer performance. The hydrologic model, with complex configurations and powerful performance, facilitates a broader understanding of the effects of climate and soil in hydrologic partitioning. However, the more complex the model is, the more effort and time is required to drive the model, and the more parameters it uses, the less accessible to the user and less applicable to the ungauged watershed. Rather, a parsimonious hydrologic model may be effective in hydrologic modeling of the ungauged watershed. Thus, a semi-distributed hydrologic partitioning model was developed with minimal composition and number of parameters to improve applicability. In this study, the validity and performance of the proposed model were confirmed by applying it to the Namgang Dam, Andong Dam, Hapcheon Dam, and Milyang Dam watersheds among the Nakdong River watersheds. From the results of the application, it was confirmed that despite the simple model structure, the hydrologic partitioning process of the watershed can be modeled relatively well through three vertical layers comprising the surface layer, the soil layer, and the aquifer. Additionally, discussions were conducted on antecedent soil moisture conditions widely applied to stormwater estimation using the soil moisture data simulated by the proposed model.

• 물과 미래
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• 제20권2호
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• pp.139-150
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• 1987

본 연구는 우리나라의 확율강우량도 작성을 위한 수문해석기법을 개발제시하는 것을 내용으로 하고 있다. 강우량계열의 적정분포형검정과정에서는 변수변환정규분포(Y-k법)등 11개의 연속확율분포형을 적용하였으며, 각 지속기간별 연최대강우량자료에 대한 수문해석을 실시하였다. 최적분포형 선정을 위한 적합도검정은 $-test와 Kolmogorov-Smirnov test에 의거하였으며 계급구간은 등간격으로 취하였다. 서울, 인천, 부산 및 광주지점의 강우지속기간 10분, 60분, 6시간 및 24시간에 대한 연최대 강우량에 각종 확율분포를 적용하고, 분포형의 적용상 특성과 강우량 자료집단의 특성을 고려하여 최적확율분포형을 설정하였다. 이와같은 해석기법으로 설정된 최적확율분포형은 종전의 방법으로 얻어진 적정분포형 보다도 자료면에서 확장된 자료집단일 뿐 아니라 확대검정된 합리적인 결과라고 생각된다.

• 대한토목학회논문집
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• 제12권1호
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• pp.159-166
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• 1992

Landsat 자료는 그 자체만으로도 가치가 있으며, 이를 양적인 정보로 분류하여 실사용자에게 전수하면 그 가치는 더욱 증대될 것이다. 이러한 관점에서 Landsat 자료로부터 수문 매개변수를 양적으로 산정하고, 이를 이용할 수문학자에게 전수될 수 있는 수문모델을 개발하는 것은 매우 가치가 있다 이 연구는 그러한 목적을 수행하기 위한 첫단계이다. 본 논문은 토지조건과 유출의 관계로 결정될 수 있는 수문모델의 결과와 그 모텔 에 적용할 수 있는 사진영상 및 수치영상의 해석절차를 포함한다. 결국 이 논문은 Landsat 영상이 매우 유용하고 경제적이며, 광역의 유역에서 수문모델에 대하여 충분히 정확한 정보를 제공한다는 것을 보인다.

• 한국물환경학회지
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• 제25권3호
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• pp.432-440
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• 2009

The effect of selecting hydrologic item for calculating objective function on calibration of stream flow was evaluated by Hydrologic Simulation Porgram-Fortran (HSPF) linked with Model Independent Parameter Optimizer (PEST). Daily and monthly stream flow and flow duration were used to calculate objective function. Automated calibration focused on monthly stream was proper to analyze seasonal or yearly water budget but not proper to predict daily stream flow or percent chance flow exceeded. Calibration result focused on flow duration is proper to predict precent chance flow exceeded but not proper to analyze water budget or predict peak flow. These results indicate that hydrologic item calculated for objective function on calibration procedure could influence calibration results and watershed modeler should select carefully hydrologic item for the purpose of model application. Current, the criteria of stream flow of Korean TMDL is generated based on percent chance flow exceeded, so flow duration should be included to calculate objective function on calibration procedure for the estimation of criteria of stream flow using hydrologic model.

• 한국관개배수논문집
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• 제17권2호
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• pp.28-34
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• 2010

This study re-exams hydrologic stability on spillway outlet capacity of agricultural reservoirs using hydrologic data with current rainfall condition instead of project hydrologic data applied at design on Backgok reservoir located in Chungbuk province. It is concluded that Backgok reservoir is not hydrologically stable and therefore structural measures including the extension of spillway and non structural measures should be taken. Continuous basic plan for river maintenance including additional bank reinforcement to bottom river shall be carried out. Due to high peak flood with more than 290% compared to 200 year frequency probability flood which was design standard of the past in view of the results of calculating PMF according to revised design standard for reservoirs, there could a problem for securing rationality in case of applying PMF with design flood. Therefore, hydrological stability, construction, and maintenance cost shall be synthetically studied and reasonal application shall be made if the decision is made on applying PMF with design flood.

• 물과 미래
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• 제23권4호
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• pp.421-434
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• 1990

Horton의 차수법칙을 이용한 지형학적 수문응답모델로서 하천유역 상호간의 수문학정 상사성 문제를 해석하였다. 지형학적 응답함수의 구성은 Nash 모델을 이용하였으며, 응답함수의 최적화는 불완전 감미함수와 Rosso가 유도한 회귀방정식을 이용하였다. 본 방법의 적용성을 검토하기 위해 평창강 유역, 위천유역 그리고 보청천 유역에 대한 실측치를 이용하였으며, 수문응답에 대한 재현성을 모멘트법과 비교하였다. 분석결과 응답모델과 무차원 순간단위도는 미계측 유역의 유출해석이나 유역의 상사상 해석에 대해 적용할 수 있다고 판단되었다.