This study is aimed at the development of a runoff forecasting model to solve the uncertainties occurring in the process of rainfall-runoff modeling and improve the modeling accuracy of the stream runoff forecasting. The study area is the downstream of Naeseung-chun. Therefore, time-dependent data was obtained from the Wolpo water level gauging station. 11 and 2 out of total 13 flood events were selected for the training and testing set of model. The model performance was improved as the measuring time interval(Tm) was smaller than the sampling time interval(Ts). The Neuro-Fuzzy(NF) and TANK models can give more accurate runoff forecasts up to 4 hours ahead than the Feed Forward Multilayer Neural Network(FFNN) model in standard above the Determination coefficient(R2) 0.7.

Revetment Mattress/Filter is the porous structure filled fillers in meshed structure so that it can use the fillers of various sizes and form various pores. The porous structure of the Mattress/Filter increases drainage so that it decreases the energy and velocity of flow therefore the tractive force is decreased and the erosion of revetment is mitigated. The filler of Mattress/Filter uses gravels, waste concretes and slags so that the surface is rough and the roughness coefficient increases and the increase of the roughness coefficient decreases flow velocity and tractive force. On the other hand Mattress/Filter and vegetation are combined so that the increase of roughness coefficient and flow velocity still more progress therefore the effect of decrease of tractive force is increased after a few months have passed since the Mattress/Filter is constructed so that the vegetation is developed and be stabilized. The vegetation channel of Mattress/Filter is set up and the inspection comes into operation by varing flowrate and vegetation spacing to examine these characters of the Mattress/Filter. The coefficent of flow velocity U/U*' is decreased exponentially as vegetation desity aH' or λ is increased and the coefficient of friction f is increased as vegetation desity aH' is increased but decreased as the coefficent of flow velocity U/U*' is increased. The effective tractive force F0 is decreased exponentially as the vegetation desity aH' is increased. From the inspection the results are obtained that the porous and vegetation structure of the revetment Mattress/Filter system increases the coefficient of friction of revetment so that flow velocity and effective are decreased therefore greatly contributes the stability of the revetment.

Aquatic plants grow in water with photosynthesis and purify water quality as taking organic and inorganic matter in water. Polluted water in stagnant stream channel where nutritive salts load is great can be purified by activities of aquatic plants. Aquatic plants should be fixed to bed easily to plant and sustainable environment is needed. So in this study, Mattress/Filter system is suggested to plant aquatic plant in stagnant stream channel. In the result of study, coverage of Phragmites australis, Zizania latifolia and Typha angustifolia which planted in mattress was 78%, 62% and 82% and numbers of species in each mattress system were 7, 11, 3. The evenness index of each mattress system was 0.86, 0.91 and 0.79 and diversity index of each mattress system was 1.67, 2.18 and 0.87. Removal rates of phosphorus at Phragmites australis, Zizania latifolia and Typha angustifolia which planted in mattress were 68.7%, 62.7%, 55.3% and removal rates of nitrogen of them were 79.8%, 74.7%, 64.9%. The removal rate of nitrogen was greater than phosphorus at all system and both removal rates were greater at Phragmites australis than at Zizania latifolia and at Typha angustifolia the rate was the least. Removal rates of PO4-3, NH4-N, NO3-N at Phragmites australis were 57.4%, 52.8%, 47.8% and at Zizania latifolia were 82.6%, 77.2%, 67.5% and at Typha angustifolia were 80.6%, 73.7%, 64.3%. It seems that removal effect is great by the planted mattress system.

도시화에 따라 인구집중과 광역화로 인하여 자연환경이 크게 변화하였으며, 특히 인간의 활동은 새로운 유출양상을 가져오는 원인이 되었다. 본 연구에서는 도시의 개발에 따른 도시화 전후의 지형인자가 변화함으로써 야기되는 유출변화 특성을 해석하였다. 도시화유역에서의 유출에 ILLUDAS 모형을 이용하였으며, 다음과 같은 결론을 얻었다. 도시화 전후의 첨두발생시간을 살펴보면, 약 15∼35 분 정도 단축되었으며, 도시화 후의 첨두홍수량은 최대 60 % 정도 증가

본 연구에서는 터널구간에서 예상되는 지하수의 유동에 관한 현상을 규명하기 위하여 지하수 유동시스템의 거동을 3차원으로 해석하였으며, 터널구간의 설계와 시공기법을 선정하는데 해석견과를 활용토록 하고, 건설기간 중에 지하수 유동과 관련한 시공상의 장애를 사전에 파악하여 대책을 수립하는데 필요한 정보로 활용할 수 있도록 하였다. 대상터널은 편도 2차선인 2개의 평행터널인 법기터널 구간으로써 시추조사 및 투수시험을 실시하여 MODFLOW 모델의 매개변수를 추정

본 연구의 목적은 홍수유출해석을 위한 확정론적 유출모형의 개발에 있으며, 유출과정은 비 선형으로 취급하여 단순화시킨 개념적 모형을 유역유출모형으로 제시하였다. 개념적 모형의 구조는 지표유출을 일으키는 지표면과 지표하유출을 일으키는 토양층으로 구분하고 이들 각 구조를 지표와 지표하로 나누어 유출과정을 개념화하였으며, 지표흐름의 지체효과는 부탱크를 도입하여 나타내었다. 지표하 구조에서 중간 및 지표하 흐름의 성분들은 수치 filter를 이용하여 분리하였다.

본 연구는 미 계측유역이나 자료가 결핍된 유역에서 지리정보시스템을 이용하여 지형학적 순간단위도(GIS-GIUH)를 해석하는데 목적이 있으며, IHP 위천대표시험유역의 6개지점(동곡, 고로, 미성, 병천, 효령, 무성)에 대하여 강우-유출해석을 실시하였다. 지형학적 순간단위도의 분석에는 본 연구에서 제안한 GIS-GIUH 모형과 Rosso-GIUH 모형을 이용하여 계산된 결과를 실측유출수문곡선과 비교하였다. 분석결과 GIS-GIUH 모형이 Rosso-GI

하상보호용 사석은 초기 거동조건의 범위를 넘어 한계조건에 도달하면 흐름에 의해서 각각의 자갈 또는 석재가 분리되면서 점진적으로 파괴된다. 이와 반대로 하상보호용 매트리스의 경우는 비록 초기 거동조건의 범위를 넘어 한계조건에 도달할지라도 매트리스 철망에 의해 각각의 자갈 또는 석재의 분리가 억제가 됨을 알 수 있었다. 비록 변형된 하상보호용 매트리스일지라도 새로운 형태의 평형을 얻을 수 있으며, 더 이상의 변형과 나쁜 조건에서도 저항할 수 있음을 확인하였