• 한국습지학회지
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• 제11권2호
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• pp.89-98
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• 2009

본 연구는 하천종단면에 정보엔트로피이론을 적용하여 평균하천경사, 하천경사 및 하천종단고도 결정방법을 제시하였다. 최대화된 엔트로피는 제약조건하에서 일정한 하천종단면의 확률분포를 만들며, 이와 같은 관계를 이용하여 평균하천경사, 하천경사 및 하천종단고도 산정식을 유도하였다. 충북 지방하천 정비기본계획에서 얻은 달천유역의 실측된 지형학적 인자를 사용하여 매개변수를 최소자승법으로 결정하였다. 유도된 평균하천경사와 하천종단고도식을 실제유역에 적용하였으며, 실측치와 잘 일치함을 나타낸다. 본 연구의 결과로부터 평균하천경사와 하천종단고도의 결정에 직접 적용할수 있을 것으로 판단된다.

• 한국조경학회지
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• 제30권3호
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• pp.73-85
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• 2002

The purpose of this study was to develop prediction models for plant species abundance by stream restoration. Generally the stream plant is affected by stream gemophology. So in this study, the relationship between the vegetation abundance and stream gemophology was developed by multiple regression analysis. The stream characteristics utilized in this study were longitudinal slope, transectional slope, micro-landforms through the longitudinal direction, riparian width and geometric mean diameter and biggest diameter of bed material, and cumulated coarse and fine sand weight portion. The Pyungchang River with mountainous watershed and the Kyungan stream and the Bokha stream in the agricultural region were selected and vegetation species abundance and stream characteristics were documented from the site at 2~3km intervals from the upper stream to the lower. The Models for predicting the vegetation abundance were developed by multiple regression analysis using SPSS statistics package. The linear relationship between the dependant(species abundance) and independant(stream characteristics) variables was tested by a graphical method. Longitudinal and transectional slope had a nonlinear relationship with species abundance. In the next step, the independance between the independant variables was tested and the correlation between independant and dependant variables was tested by the Pearson bivariate correlation test. The selected independant variables were transectional slope, riparian width, and cumulated fine sand weight portion. From the multiple regression analysis, the $R^2$for the Pyungchang river, Kyungan stream, Bokga stream were 0.651, 0.512 and 0.240 respectively. The natural stream configuration in the Pyungchang river had the best result and the lower $R^2$for Kyunan and Bokha stream were due to human impact which disturbed the natural ecosystem. The lowest $R^2$for the Bokha stream was due to the shifting sandy bed. If the stream bed is fugitive, the prediction model may not be valid. Using the multiple regression models, the vegetation abundance could be predicted with stream characteristics such as, transection slope, riaparian width, cumulated fine sand weigth portion, after stream restoration.

• 대한토목학회논문집
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• 제26권3B호
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• pp.241-251
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• 2006

우리나라의 효율적인 하천유역관리를 위해서는 유역 및 하천과 관련된 지형적 수문학적 특성인자들의 신속하고 정확한 추출이 요구된다. 최근, 원격탐사기법과 GIS기법이 도입으로 이것이 가능하게 되었으며 이 기법들을 이용하여 여러 활용 가능한 자료들을 구축하고 있는 실정이다. 본 연구에서는 북한강유역을 대상으로 GIS기법에 의해 1:5,000 NGIS자료로부터 추출하여 DEM과 하천망을 생성하였다. 이를 이용하여 하천특성인자와 유역특성인자들을 추출함으로써 단위유역별 지형학적 특성을 파악하였다. 또한 대상유역을 상류, 중류, 하류 지점으로 구분하여 지형학적 인자를 추출하고 그 특성을 분석하였으며 선형 및 비선형 회귀곡선을 이용하여 그 인자들 간의 상관관계를 분석함으로써 전체유역 뿐만 아니라 상류, 중류, 하류 유역에 특별히 영향을 끼치는 하천특성인자 및 유역특성인자를 구별해 낼 수 있었다. 그 결과 하천특성인자는 전체유역, 상류, 중류, 하류 유역 모두에 크게 영향을 끼치는 인자임을 알 수 있었고, 유역특성인자 중 전체유역, 상류, 중류, 하류 유역에 공통적으로 영향을 끼치는 인자는 유역면적에 대한 총하천연장과 하천총수 임을 알 수 있었다.

• 한국환경복원기술학회지
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• 제4권4호
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• pp.1-11
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• 2001

This study was carried out to analyze the characteristics of forest environmental and stream morphological factors by using the quantification theory(I) for evaluation of the watershed stability. Present annual mean sediment yield of erosion control dams were investigated in 167 sites of erosion control dam constructed during 1986 to 1999 in Gyeongbuk. The results obtained from this study were summarized as follows; According to the coefficients of partial correlation, each factor affecting to sediment was shown in order of gravel contents, number of first streams order, number of total streams, length of total streams, forest type, length of main stream, parent rock, stand age, soil texture, stream order, slope gradient, soil depth and aspect. Descriptions of class I were as follow; Igneous rock of parent rock, hardwood stands of forest type, less than 20 year of stand age, less than 30cm of soil depth, sandy clay loam of soil texture, more than 41% of gravel contents, south~east of aspect, 2,501~3,500m of length of main stream, 21~25 of number of total streams, 5,501~10,000m of length of total streams, 3 or more than 4 of stream order, more than 16 of number of first stream orders and more than $31^{\circ}$ of slope gradient. Descriptions of class II were as follow; Metamorphic rock of parent rock, coniferous stands of forest type, more than 25 year of stand age, 31~40cm of soil depth, silt loam of soil texture, 11~20% of gravel contents, north~west of aspect, 2,501~3,500m of length of main stream, 16~20 of number of total streams, 3,501~5,500m of length of total streams, 3 of stream order, 11~15 of number of first stream orders and more than $31^{\circ}$ of slope gradient. Descriptions of class III were as follow; Sedimentary rock of parent rock, mixed stands of forest type, more than 25 year of stand age, more than 51cm of soil depth, silty clay loam of soil texture, less than 10% of gravel contents, south~west of aspect, less than 500m of length of main stream, less than 5 of number of total streams, less than 1,000m of length of total streams, less than 1 of stream order, less than 2 of number of first stream orders and less than $25^{\circ}$ of slope gradient. The prediction method of suitable site for erosion control dam divided into class I, II, and III for the convenience of use. The score of class I evaluated as a very unstable area was more than 8.4494. A score of class II was 8.4493 to 6.0452, it was evaluated as a moderate stable area, and class III was less than 6.0541, it was evaluated as a very stable area.

• Ecology and Resilient Infrastructure
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• 제2권2호
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• pp.118-127
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• 2015

하천은 구간에 따라 하도의 지형학적인 특성이 다양하기 때문에 수리 및 하도 특성 평가를 위해서는 하천의 유형을 분류할 필요가 있다. 또한 하도 특성에 대한 정량적 평가체계는 하천 유형의 특성이 반영되어야 한다. 따라서, 본 연구에서는 하천분류체계의 한국 하천에 대한 적용성을 검토하기 위하여 Rosgen의 하천분류체계와 Yamamoto의 하천분류체계를 비교, 분석하였고, 남강을 사례로 그 적용성을 검토하였다. 하천 지형학적인 측면에서 우리나라의 지방 및 국가하천의 평균하상경사와 종적 연속성을 고려하기 위해서는 하천 지형학적인 측면에서 Yamamoto의 하천분류체계가 적용성이 높은 것으로 판단된다. 또한, 하상재료의 측면에서 Rosgen 분류체계가 Yamamoto의 분류체계보다는 하상경사와의 상관성이 낮게 나타났다. 반면에 Yamamoto의 분류체계는 하상경사에 따른 토사분급 (수리분급)을 반영할 수 있는 것으로 확인되었다. 남강에 대하여 얻어진 결과에 의하면, Rosgen의 분류체계로서는 하상경사와 하상재료의 관계로서 하천유형을 분류할 수 없으나, Yamamoto 분류체계는 그 상관성을 입증할 수 있었다. 다만, 자연하천에 대하여 추가적인 적용성 검토가 필요하다. 하도 특성 평가체계에 적용할 수 있는 3개의 하천유형을 결정하여 제시하였다.

• 한국환경과학회지
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• 제21권6호
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• pp.725-738
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• 2012

Recently, a variety of GIS-based tools enabling to generate topographic parameters for hydrologic and hydraulic researches have been developed. However, most of GIS-based tools are usually insufficient to estimate and visualize river channel slopes especially along the river network, which can be possibly utilized for many hydraulic equations such as Manning's formula. Many existing GIS-based tools have simply averaged cell-based slopes for the other advanced level of hydrologic units as likely as the mean watershed slope, thus that the river channel slope from the simple approach resulted in the inaccurate channel slope particularly for the mountain region where the slope varies significantly along the downstream direction. The paper aims to provide several more advanced GIS-based methodologies to assess the river channel slopes along the given river network. The developed algorithms were integrated with a newly developed tool named RiverSlope, which adapted theoretical formulas of river hydraulics to calculate channel slopes. For the study area, Han stream in the Jeju island was selected, where the channel slopes have a tendency to rapidly change the upstream near the Halla mountain and sustain the mild slope adjacent to watershed outlet heading for the ocean. The paper compared the simple slope method from the Arc Hydro, with other more complicated methods. The results are discussed to decide better approaches based on the given conditions.

• Wind and Structures
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• 제12권3호
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• pp.219-237
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• 2009

This study examines the accuracy of large-eddy simulation (LES) to simulate the flow around a large irregular sloping complex terrain. Typically, real built up environments are surrounded by complex terrain geometries with many features. The complex terrain surrounding The Hong Kong University of Science and Technology campus was modelled and the flow over an uphill slope was simulated. The simulated results, including mean velocity profiles and turbulence intensities, were compared with the flow characteristics measured in a wind tunnel model test. Given the size of the domain and the corresponding constraints on the resolution of the simulation, the mean velocity components within the boundary layer flow, especially in the stream-wise direction were found to be reasonably well replicated by the LES. The turbulence intensity values were found to differ from the wind tunnel results in the building recirculation zones, mostly due to the constraints placed on spatial and temporal resolutions. Based on the validated mean velocity profile results, the flow-structure interactions around these buildings and the surrounding terrain were examined.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2006년도 학술발표회 논문집
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• pp.613-617
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• 2006

개별 하천에 존재하는 하상재료는 상류의 지질특성과 유수에 의한 작용력의 특성을 반영하고 있으며 유수에 의한 작용력은 하상경사와 유량규모에 지배적인 영향을 받는다. 산본 황일(山本 晃一)(1994)에 의하면 자연하천에서 동일한 경사를 가지는 하도 구간은 하상재료, 소류력, 저수로 폭, 수심 등이 대체로 동일한 값을 나타내고 있으며, 하도 특성을 지배하는 주요인자로 각 하천의 평균연최대유량, 하상재료의 대표입경, 하상경사 등을 설정하고 있다. 하상재료는 하도의 물리적, 생태적 특성을 지배하는 대표적인 인자로 의미가 있으나 국내에서는 이와 관련된 연구가 미비한 실정이다. 본 연구에서는 국내 하천의 하도 특성을 분석하는 기초연구로서 대표하천에 대한 하상재료를 채취하여 분석하였으며 이를 분급도와 하상경사와의 관계로 도시하여 하상재료 분포 특성을 분석하였으며 이를 일본 하천의 하상재료 특성과 비교하였다. 분석결과에 의하면 분급도, 무차원 소류력, 하상경사와의 관계 분석을 통해서 자갈과 모래하천은 그 특성이 뚜렷이 구분됨을 확인할 수 있었으며, 하상경사와 대표입경의 관계도 모래와 자갈을 구분하여 접근하여야 함을 확인하였다.

• 한국환경생태학회지
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• 제29권2호
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• pp.184-191
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• 2015

This study aimed to analyze characteristics of the seasonal habitat use of reintroduced Long-tailed Gorals (n=7) in Woraksan (mountain) National Park. We collected 10,721 goral coordinates in Woraksan (mountain) National Park via transmitters, and analyzed habitat use (e.g., aspect, distance from stream and road) from November 2006 to January 2013. Aspect use was southwest (22.6 %), and seasonal aspect use had a southwestern slope (in the spring, summer, and autumn). A northwestern aspect was detected in winter, but slope of $30^{\circ}{\sim}35^{\circ}$ (19.0 %) was used regardless of the season and mean elevation use was 500 m. Moreover, seasonal use was higher in the summer and lower in the winter and spring. The distance from the stream was mainly 50 m in 17.2 %, except in the winter (distance of 300 m), and it was within 50 m in the spring, summer, and autumn. The distance from the road was 100 m in 25.7 %, and seasonal use was within 100 m except for the winter. Thus, we examined significant differences in the habitat use of reintroduced gorals in Woraksan (mountain), and provide elementary data for habitat stabilization of Woraksan (mountain) National Park where goral restoration has advanced.

• 한국환경생태학회지
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• 제22권2호
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• pp.184-191
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• 2008

어류개체군에 대한 탁수의 영향을 파악하고자, 2004년부터 2005년까지 탁수하천(대기, 자운천)과 비탁수하천(봉산천, 계방천)에 분포하는 금강모치 개체군의 체장-체중 관계와 비만도지수의 변화를 알아보았다. 탁수하천과 비탁수하천간의 금강모치 평균전장을 비교해본 결과, 유의한 차이가 없는 것으로 나타났다. 남한강에서 체장-체중 관계에 따른 회귀계수 b값은 봉산천에서 3.21, 그리고 대기천에서 3.07로 나타났다. 이에 반하여, 북한강에 위치한 탁수하천의 회귀계수 b값은 비탁수하천의 값보다 약간 높았다. 그 값은 계방천에서 3.20, 자운천에서 3.23으로 각각 나타났다. 우리의 연구 결과는 금강모치 개체군 단계에서 만성 탁수의 영향이 적음을 보여준다.