• 환경영향평가
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• 제9권1호
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• pp.25-37
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• 2000

This paper presents a study of hydrological and hydraulic model applications in environmental impact statements which were submitted during recent years in Korea. In many cases (almost 70 %), the hydrological and hydraulic changes were neglected from the impact identification processes, even if the proposed actions would cause significant impacts on those environmental items. In most cases where the hydrological and hydraulic impacts were predicted, simple equations were used as an impact prediction tool. Computer models were used in very few cases(5%). Even in these few cases, models were improperly applied and thus the predicted impacts would not be reliable. The improper applications and the impact neglections are attributed to the fact that there are no available model application guidelines as well as no requirements by the review agency. The effects of mitigation measures were not analyzed in most cases. Again, these can be attributed to no formal guidelines available for impact predictions until now. A brief guideline is presented in this paper. This study suggested that the model application should be required and guided in detail by the review agency. It is also suggested that the hydrological and hydraulic items shoud be integrated with the water quality predictions in future, since the non-point source pollution runoff is based on the hydrologic phenomena and the water quality reactions on the hydraulic nature.

• 한국농공학회지
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• 제21권2호
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• pp.49-80
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• 1979

This report summarizes the findings of investigations and studies conducted through fieldtrips and an opinionnaire over a period of 11 months from July 1978 to May 1979 on various problems involved in hydraulic and hydrological phases of 12 large-scale comprehensive agricultural development project, Pyeongtaek-Kumgang, 1st stage and 2nd stage of Yongsangang, Kyungju, Gyehwado, Sapgyocheon, Imjin, Changryung, Miho, Namgang and Nakdonggang which are either completed or imdrocess of implentation for rural modernization in Korea.

• 한국농공학회논문집
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• 제65권1호
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• pp.41-49
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• 2023

To utilize the hydraulic and hydrological models when simulating floods in agricultural watersheds, it is necessary to consider agricultural reservoirs, farmland, and farmland drainage system, which are characteristics of agricultural watersheds. However, most of them are developed individually by different researchers, also, each model has a different simulation scope, so it is hard to use them integrally. As a result, there is a need to link each hydraulic and hydrological model. Therefore, this study established an integrated flood simulation system for the comprehensive flood simulation of agricultural reservoir watersheds. The system can be applied easily to various watersheds because historical weather data and the SSP (Shared Socio-economic Pathways) climate change scenario database of ninety weather stations were built-in. Individual hydraulic and hydrological models were coded and coupled through Python. The system consists of multiplicative random cascade model, Clark unit hydrograph model, frequency analysis model, HEC-5 (Hydrologic Engineering Center-5), HEC-RAS (Hydrologic Engineering Center-River Analysis System), and farmland drainage simulation model. In the case of external models with limitations in conceptualization, such as HEC-5 and HEC-RAS, the python interpreter approaches the operating system and gives commands to run the models. All models except two are built based on the logical concept.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2006년도 학술발표회 논문집
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• pp.758-763
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• 2006

Statistical concepts and methods are routinely utilized in a number of design and management problems in engineering hydrology. This is because most of hydrological processes have some degree of randomness and uncertainty. Thus, the concepts of risk and uncertainty are commonly utilized for designing and evaluating hydraulic structures such as spillways and dikes. Therefore, in this study, uncertainty analysis considering the variance of design floods is performed to evaluate the uncertainty of the hydrologic risk of flood related hydraulic structures using frequency analysis.

• 한국농림기상학회지
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• 제11권4호
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• pp.151-161
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• 2009

토양수리특성을 규명하는 것은 사면에서의 수문과정을 이해하는 과정에서 중요한 부분이다. 이 연구에서는 토양공극발달 및 수리학적 특성의 시간적인 변화특성에 대해서 조사하였다. 특히, 대공극 흐름이나 수리전도도와 관련된 특성들을 설마천 유역의 범륜사 사면과 광릉연구유역의 원두부 소사면에서 관측하였다. 연직 흐름의 측정을 위해 사용된 기기는 장력 침투계로 약 8개월동안 토양층 표면의 수리전도도를 측정하였다. 측정된 결과는 3월, 6월, 9월의 수리전도도가 상대적으로 크지만, 5월과 10월의 경우는 낮은 값을 보여준다. 이는 식생의 세근활동 등과 관련된 공극구조의 발달양상과 선행강우사상으로 인한 토양수분의 영향으로 설명될 수 있다. 침투과정에서 있어서 대공극은 산림 유역에서의 수리전도도에 미치는 영향은 대단히 크며, 수문학적 과정에 있어서도 매우 중요한 기작이다. 본 연구는 현장에서 측정된 토양 수리특성의 시간적 불균일성을 보여주는 사례로 사면에서의 침투과정이 동적인 과정임을 보여주고 있고, 관련된 다양한 토양 수리학적 특성들은 국내 산지사면에서 발생되는 수문기작을 이해하는데 중요한 기초 자료가 된다.

• 한국터널지하공간학회 논문집
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• 제13권2호
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• pp.97-114
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• 2011

산악터널이 건설되는 지역에 있는 우물이나 작은 하천들은 흔히 주민들의 일상생활용수원으로 사용되고 있다. 이때 터널이 굴착됨에 따라 우물의 수위 저하와 같은 문제들이 발생할 수 있다. 따라서 본 연구에서는 설계단계에서 터널 주위의 지하수에 대한 부정적인 영향을 경감시키기 위해 MODFOLOW와 같은 수치모델링 기법을 사용하여 터널내 지하수 유입량과 지하수위 저하 지역에 대한 평가를 실시하였다. 또한 수문학적인 방법에 의해서 터널주변 지역의 지하수의 용수량을 평가하였다.

• 물과 미래
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• 제18권3호
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• pp.265-270
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• 1985

The prediction of a design-flood hydrograph at a particular site on a river may be based on the derivation of discharge or stage hydrograph at an upstream section, togeater with a method to route this hydrograph along the rest of river. On the other hand, flood routing methods provide a useful tool for the analysis of flooding in all but the smaller catchment, and these methods are largely stored into hydrological method and hydraulic method. Although the Muskingum Method as a hydrological method ignores dynamic effects on the flood wave, Muskingum-Cunge Method based on hydraulic method is possible to improve the method so that it gives a good approximation to the solution of the linear convective-diffusion equation. This is made on the basis of the finite diffeience equation for the Muskingum Method. In the study, the outflows predicted by Muskingum-Cunge Method are campared with the observed outflows of the Pyung Chang River.

• Advances in environmental research
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• 제7권3호
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• pp.161-175
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• 2018

Krishna River is significantly affected due to Srisailam dam from past 30 years. The impact of this hydraulic structure drastically reduced the minimum flow regime on the downstream, which made the river nearing to decaying stage. In the present paper, Environmental Flow called minimum flow values released for the dam are estimated with the help of three hydrological methods viz., Range of variability Approach (RVA), Desktop Reserve Model (DRM), and Global Environmental Flow Calculator (GEFC). DRM method suggested considering the intermediate values obtained from among the three methods to preserve the ecosystem on the downstream of the river, which amounts to an average annual allocation of 9378 Million Cubic Meter (MCM) which is equal to 23.11% of mean annual flow (MAF). In this regard GEFC and RVA methods accounted for 22% and 31.04% of MAF respectively. The results indicate that current reservoir operation policy is causing a severe hydrological alteration in the high flow season especially in the month of July. The study concluded that in the case of non-availability of environmental information, hydrological indicators can be used to provide the basic assessment of environmental flow requirements. It is inferred from the results obtained from the study, that the new reservoir operations can fulfil human water needs without disturbing Environmental Flow Requirements.

• 한국토양비료학회지
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• 제47권5호
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• pp.340-344
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• 2014

Compost and gypsum can be used to ameliorate soil physicochemical properties in reclaimed tidal lands as an organic and inorganic amendment, respectively. To evaluate effects of compost and gypsum on soil water movement and retention as a soil physical property, we measured the soil's saturated hydraulic conductivity and field capacity after treating the soil collected in a reclaimed tidal land with compost and gypsum. Saturated hydraulic conductivity of soil increased when compost was applied at the conventional application rate of $30Mg\;ha^{-1}$. However, the further application of compost insignificantly (P > 0.05) increased saturated hydraulic conductivity. On the other hand, additional gypsum application significantly increased soil saturated hydraulic conductivity while it decreased soil field capacity, implying the possible effect of gypsum on flocculating soil colloidal particles. The results in this study suggested that compost and gypsum can be used to improve hydrological properties of reclaimed tidal lands through increasing soil water retention and movement, respectively.

• 한국습지학회지
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• 제18권2호
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• pp.148-153
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• 2016

하도 홍수추적과 관련하여 하천에서의 시 공간적 홍수파를 해석하는데 수리학적 방법과 수문학적 방법이 일반적으로 많이 이용되어 왔다. 수문학적 홍수추적 방법은 수리학적 방법에 비해 수행하기에는 비교적 간단하면서도 합리적인 정확성을 지닌다. 수문학적 홍수추적 방법 중 광범위하게 적용되어지고 있는 Muskingum 모형의 중요 변수인 저류상수는 유하시간과 매우 유사한 값을 가진다. 이러한 점에 착안하여 본 연구에서는 저류상수를 산정하기 위해 HEC-RAS를 이용한 유하시간을 산정하고, 하도거리, 하도경사, 유량 자료를 이용하여 유하시간에 대한 비선형 회귀곡선식을 개발하였다. 비선형 회귀곡선에 의해서 산정된 저류상수를 Muskingum 모형에 대입하여 구한 유출량은 HEC-RAS 1차원 부정류 모의를 적용하여 산정된 유출량과 비교하였다. 이와 함께 본 연구에서는 가중인자에 대한 영향 및 상하류 사이의 구간 분할에 대해서 검토하였는데, 그 결과 가중인자 값이 클수록 첨두홍수량이 올라가는 것으로 나타났으며, 구간 분할을 많이 할수록 RMSE가 감소하는 것으로 나타났다.