• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.1306-1310
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• 2009

The roughness coefficients were estimated by the Manning's equation for the measured stage and flow velocity of Bocheong stream basin in Kum river. The relationships between the estimated roughness coefficients and the geomorphologic factors were formulated by the linear, logarithmic, exponential and power type function, thereafter correlation equations were presented. The correlation analysis was performed between the measured stream length and the basin area of Bocheong stream basin by the linear, logarithmic, exponential and power type function, and correlation equation for the stream length was given. The roughness coefficient has strong correlationship with stream slope, but low correlation coefficients with stream length and basin area. For the correlationship with the roughness coefficients and the stream slope, the logarithmic type function has the smallest correlation coefficient, on the other hand, the exponential type function has the largest correlation coefficient. For the relationship between the stream length and the basin area, the correlation coefficient of the logarithmic type function shows the smallest value, linear type function shows the largest value.

• 한국환경생태학회지
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• 제28권3호
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• pp.302-313
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• 2014

모래형 하천과 자갈형 하천의 어류군집 특성을 비교하기 위해 4개의 하천을 선정하여 계절별 조사를 실시하였으며, 출현한 어종 중 한국고유종은 Acheilognathus gracilis 외 24종으로 확인되었다. 홍천강과 무주남대천의 우점종은 Zacco koreanus로 각각 39.9%, 28.4%를 차지하였으며, 양화천은 Rhodeus notatus가 13.6%, 갑천은 Z. platypus가 26.0%로 우점하였다. 군집분석 결과 우점도지수는 0.27~0.63, 다양도지수는 1.92~2.67, 균등도지수는 0.6~0.79, 풍부도지수는 3.09~3.53의 범위로 나타났으며, 우점도지수는 홍천강에서 가장 높고, 다양도, 균등도, 풍부도지수는 양화천에서 가장 높게 나타났다. 내성도 길드 분석 결과 하상구조물이 다양한 홍천강과 무주남대천은 민감종이 각각 50.1%와 46.4%로 비교적 높은 비율을 차지하였고, 모래 하상이 높은 양화천과 갑천은 민감종이 각각 0.5%와 5.3%의 희소한 비율을 차지하였다. 하천별 출현한 어류의 종별 개체수와 하상구조를 이용하여 유사도를 분석한 결과 자갈형 하천인 홍천강과 무주남대천이 종과 개체수는 50.4%, 하상구조는 95.2%로 가장 유사하였다. IBI 분석결과 홍천강과 무주남대천이 'A등급', 양화천과 갑천이 'B등급'으로 나타났고, 주성분 분석결과 자갈형 하천과 모래형 하천의 2개의 그룹으로 구분되었다.

• 한국농공학회지
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• 제40권6호
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• pp.57-69
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• 1998

The creation of favorable water space, in our living circumferential space, is very important factor to offer rural scenery to neighbor residents. We are to introduce stream landscape arrangement technique considering favorable water environment against conventional methods. In this study, the modeling district is Seungdu small stream of Ansung river system in Pyung-Teak city, Kyonggi province, and we carried out stream landscape simulation. The arranging plans of landscape are classified ti three types. The first one is conservation type of ecological environment that can express natural characteristics of stream inherence, raise variety of living things and construct coexisting environment between human beings and the other living things. The secong one is favorable water approach type. The basic object of this type is space construction for easy approach to waterside and increase of comfortable feelings of spectators. The third one is water utilization/flood control management type. In planning of environmentally favorable landscape arrangement, this type is the most important but is likely to be ignored. This type is an arranging plan of stream landscape considering safety. Also, we developed Streams Landscape Simulation System(SLSS). This program can be used for comparison of original landscape image with simulated one. To apply SLSS on the interested stream, landscape simulation that is based on hydraulic characteristics, runoff, flow direction, detailed conditions of basin and ecosystem of stream have to be executed. In this point, developing a stereographical technique of image processing and exact study of applying plan have to be executed continually.

• Ecology and Resilient Infrastructure
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• 제2권3호
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• pp.247-254
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• 2015

Changes in land-use type can affect soil and water properties in stream ecosystems. This study examined the effects of different land-use types on biogeochemical properties and microbial activities of a stream. We collected water and sediment samples in a stream at three different sites surrounded by varying land-use types; a forest, a radish field and a rice paddy. Nitrogen contents, such as nitrate, nitrite and total nitrogen in the stream water body, showed significant differences among the sampling sites. The highest nitrogen values were recorded at the site surrounded by cropland, as fertilizer runoff impacted the stream. Soil organic matter content in the sediment showed significant differences among sites, with the highest content exhibited at the forest mouth site. These differences might be due to the organic matter in surrounding terrestrial ecosystems. Microbial activities determined by extracellular enzyme activities showed similar values throughout all sites in the water body; however, the activities in the sediments exhibited the highest values near the forest site and mirrored the soil organic matter content values. From these results, we conclude that different land-use types are important factors affecting water and sediment properties in stream ecosystems.

• 한국환경복원기술학회지
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• 제15권5호
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• pp.103-114
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• 2012

The purpose of this research is classifying stream into different types depending on various factor from the perspective of stream corridor restoration and using it as basic data, which are used to consider efficient management and planning for the healthy stream according to the characteristic by types. In this study, 130 points of location of the Nakdong river basin which consist of various geographic factors have been chosen and hierarchical cluster analysis has been carried out in these points by using biological and physiochemical factors whose health can be considered to be predicted and evaluated. As a result of cluster analysis, there were three divided types. Type A whose biology and water quality are considered the best was the highest in forest area percentage so that it was classified into natural stream. Type B was classified into a rural region stream with a mixture of urban and agricultural region. Type C, with the most damaged water quality and biology health had the most urban region surface area and was named as urban region stream. Moreover, an overall restoration strategy according to characteristic by stream types was set. By the results of correlation analysis on factors, water quality showed a high correlation with biological properties and was affected by surrounding land usage. In evaluation of streams, it proves the need to consider not only other habitat's geographical and biological factors but also the water quality and land usage factors. There needs to be further research on stream ecosystem functionality factors and structural aspects by using a more objective and total evaluation result in selecting additional index and various other specific classification methods by stream types and its restoration strategies.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.687-690
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• 2008

Currently, Stream flow analysis has been accomplished by one or two dimensional equations and was applied by simple momentum equations and fixed energy conservations which contain many reach uppermost limit. In this study, FLOW-3D using CFD(Computational Fluid Dynamics) was applied to stream flow analysis which can solve three dimensional RANS(Reynolds Averaged Navier-Stokes Equation) control equation to find out physical behavior and the effect of hydraulic structures. Numerical simulation accomplished those results was compared by using turbulence models such as $k-\varepsilon$, RNG(Renomalized Group Theory) $k-\varepsilon$ and LES(Large Eddy Simulation). Numerical analysis results have been illustrated by the turbulence energy effects, velocity of flow, water level pressure and eddy flows around the side overflow type structures at Jangwall bridge in urban stream.

• 한국지형학회지
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• 제25권2호
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• pp.1-14
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• 2018

The main objective of this paper is to classify properties of the locational environment for each debris type by calculating likelihood ratio based on the correlation between the distributions for each type of debris landform. A total of 8 thematic maps, like as elevation, slope, aspect, curvature, topographic wetness index (TWI), soil drainage, geology, and landcover including with GIS spatial information generally used in this type of debris landform analysis. The results of this study showed that the block stream had a high likelihood ratio compared to talus in areas with relatively high elevation; and concerning slope, the block stream had a high likelihood ratio in a relatively low region than talus. Concerning aspect, a clear correlation could not be analyzed for each debristype, and concerning curvature, the block stream displayed a developed slope on the more concave valley than the talus. Analysis concerning TWI, the block stream displayed a higher likelihood ratio in wider sections than talus, and concerning soil drainage, the talus and block stream both displayed a high likelihood ratio in regions with well-drained soil. The talus displayed a high likelihood ratio in the order of metamorphic rocks, sedimentary rocks, and granite, while the block stream displayed a high likelihood ratio in the order of volcanic rocks, granite, and sedimentary rocks. In addition, concerning landcover, the likelihood ratio had the most concentrated distributed compared to natural bare land only concerning talus. Based on the likelihood ratio result, it can be used as basic data for extracting the possible areas of distribution for each debris type through the GIS spatial integration method.

• 한국산림과학회지
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• 제108권2호
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• pp.224-232
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• 2019

산지계류에서 다양한 계상공작물의 설치에 따른 어류의 상부 및 하부로의 이동상태를 조사하여 분석한 결과를 요약하면 다음과 같다. 콘크리트 박스공과 같은 개방형 구조물의 경우 강우의 영향으로 유량이 늘어나는 시기에는 낙차의 높이가 줄어드는 효과가 발생하여 버들치와 같은 유영성 어류들은 상부에서 하류로의 이동과 하부에서 상부로 소상하는데 비교적 양호하였다. 또한, 1 m 미만의 돌낙차공, 돌바닥막이 등 횡단 계상구조물은 상부에서 방사한 버들치의 개체가 하부에서 재 포획되어 구조물 상부에서 하부로의 이동은 가능하였으나, 유량이 많은 장마 직후에도 하부에서 상부로의 소상은 어려운 것으로 나타났다. 특히, 3 m 이상의 사방댐 등 횡단 사방공작물도 댐의 하단부에 물빼기 구멍의 수가 적거나 어류를 위한 소통 공간이 없는 경우는 유량이 많아도 버들치의 이동에 제한을 받고 있는 것으로 나타났다. 버들치는 활발하게 행동은 하지만 계상구조물의 유형 및 구조적인 특성에 따라 이동에 제한을 받고 있다. 산지 계류에서 구조물을 설치할 때에는 구조물의 종류, 높이 및 어류서식 상태와 평소 계류에 물이 있는 지를 고려하여 어류가 소통할 수 있도록 가능한 높이를 낮추거나 개방형의 구조물을 적절하게 설치할 필요성이 있다.

• 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.

• 한국컴퓨터정보학회논문지
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• 제27권10호
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• pp.95-103
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• 2022

5G 이동통신 서비스가 점차 확대되어감에 따라 P2P 또는 D2D 응용에서 유튜부 비디오 스트리밍과 같은 트래픽 지향의 스트림 제어가 중요한 기술로 떠오르고 있다. 특히 D2D 통신에서 사용자들이 가장 많이 전송하는 데이터 스트림의 타입은 비디오 스트림이며, 이것은 대용량의 전송 스트림의 특징을 가지고 있다. D2D 통신환경에서 이런 종류의 스트림은 트래픽 혼잡의 원인을 제공할 뿐만 아니라 또한 DUE들 간의 서비스 품질을 저하시킨다. 본 논문에서는 비디오 스트림과 같은 동적 미디어 스트림의 끊김현상을 최소화하고 스트리밍 서비스 품질을 최적화하기 위해 TOSS 기법을 제안한다. 제안된 기법은 5G gNB 환경하의 3.5GHz와 28GHz의 대역폭상에서 미디어 스트림의 특성과 트래픽 타입을 분석하여 미디어 스트림을 스케줄링한다. 우리는 시뮬레이션을 통하여 제안된 기법의 성능을 알아보며, 시뮬레이션 결과는 제안된 기법이 다른 비교 기법들에 비해서 성능이 보다 우수함을 보인다.