• 한국측량학회지
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• 제17권4호
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• pp.393-401
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• 1999

비점오염원은 하천수질에 심각한 위협을 주고 있기 때문에, 이것을 해결하기 위한 비점 오염 모델이 개발되었다. 이 비점 오염 모델들은 정확한 예상을 하기 위해 정밀한 공간적 자료를 요구한다. 따라서 공간자료를 효과적으로 처리 및 분석할 수 있는 기법인 지형공간 정보체계를 이용하는 것이 효과적이라 할 수 있다. 지형공간정보체계는 비점오염 모델의 매개변수인 경사, 경사 형태, 경사 길이, SCS 곡선 지수 등을 제공한다. 따라서 이 연구는 미국 농무성과 미네소타주 연구소에서 개발된 AGNPS 모델에 지형공간정보체계를 적용하는 방법에 대하여 검토하고 지형공간정보체계를 이용한 AGNPS모델에서 요구하는 아스키 형태의 입력자료로 구축하는 인터페이스를 개발하였다.

• Environmental Engineering Research
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• 제20권3호
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• pp.290-297
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• 2015

This paper presents the evaluation of the impact of climate change on water resources and yield capacity of Asa and Kampe reservoirs. Trend analysis of mean temperature, runoff, rainfall and evapotranspiration was carried out using Mann Kendall and Sen's slope, while runoff was modeled as a function of temperature, rainfall and evapotranspiration using Artificial Neural Networks (ANN). Rainfall and runoff exhibited positive trends at the two dam sites and their upstream while forecasted ten-year runoff displayed increasing positive trend which indicates high reservoir inflow. The reservoir yield capacity estimated with the ANN forecasted runoff was higher by about 38% and 17% compared to that obtained with historical runoff at Asa and Kampe respectively. This is an indication that there is tendency for water resources of the reservoir to increase and thus more water will be available for water supply and irrigation to ensure food security.

• 산업기술연구
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• 제26권B호
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• pp.43-51
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• 2006

Through the result of calculating the deviation between the value calculated from two-dimensional number formula, one-dimensional number interpretation, and curving part water surface type calculation method, we could confirmed that the deviation is reduced more than 50% when we use curving part water surface type calculation method. Also it was confirmed that there occurs the reduction rate of maximum 59% as the result of comparing with one-dimensional number interpretation since the reduction rate of safe room height was 20%, in 500 CMS of flood water quantity when we planted the construction of levee by curving part water surface type calculation method. And therefore, we have confirmed that the curving water surface type calculation method can be used as a simple formula in rivers with water quantity less than 500 CMS that flows in and out in Jess than 90 degree angle.

• 한국안전학회지
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• 제32권2호
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• pp.112-116
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• 2017

Present study investigated the influence of time step size, turbulent eddy viscosity, and the number of layer on rapid and unsteady propagation of dam break flow. When the time step size had a value such that it resulted in Cr of 0.89, a significant numerical oscillation was observed in the vicinity of the wave front. Higher turbulent viscosity ensured smooth and mild slope of velocity and water stage compared with the flow behavior by no viscosity. The vertical velocity at the lower layer positioned near the bottom showed lower velocity compared with other layers.

• 방사선산업학회지
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• 제2권3호
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• pp.155-161
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• 2008

A hydraulic scale model was constructed to investigate the characteristics of flows and pollutant transport in laboratory. The distorted hydraulic scale model by assuming Froude similarity was adopted to represent hydrodynamics and dispersion in a river system. The scale model was composed of water reservoir, slope control part, booster pump, distributing plate and main channel. A constructed scale model will be used to present the overall concentration profiles of tracer and a research will be performed to convert the measured values using a hydraulic scale model to real field scale.

• 한국농공학회논문집
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• 제48권1호
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• pp.27-38
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• 2006

In this study, we developed a program to estimate discharge efficiently considering major hydraulic characteristic including water level, river bed, water slope and roughness coefficient in a natural river. Stream discharge was measured at Gongju gauge station located in the down stream of the Daechung Dam during normal and dry seasons from 2003 to 2004. The developed model was compared with the results from the existing rating curve at T/M gage stations, and was used for runoff analyses. Evaluating the developed river discharge estimation program, it was applied during 1983-2004 that base flow separation method and RRFS (Rainfall Runoff Forecasting System) which is based on SSARR (Streamflow Synthesis And Resevoir Regulation). The result presents the stage-discharge curve creator range at the Gong-ju is overestimated by approximately $10-20\%$, especially at the low stage. It is attributed to the hydraulic characteristics at the study. The discharge simulated by the RRFS and base flow separation, which is calibrated using the measurement at the early spring and late fall season during relatively d]v season, shows the least errors. The coefficient of roughness at Gongju station varied with the high and low water level.

• 한국환경복원기술학회지
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• 제17권1호
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• pp.163-172
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• 2014

To investigate the possibility of developing the seeding measure for river bank slope revegetation, germination experiment and early growth observation were conducted using 3 native species growing naturally around river banks such as Pennisetum alopecuroides, Phragmites communis, and Miscanthus sinensis. The applied seeding methods were 3 such as scattering seeds, tillage after scattering seeds, and covering up seed with soil after scattering seeds. According to seeding methods, germination experiment and early growth observation were carried out on nursery bed soil in greenhouse. As results of this study, all the 3 native plant species' germination ratio and growth in length on nursery bed soil were highest on the seeding method of covering up seed with soil. Also it was verified by Duncan's multiple range test that the germination ratio and growth in length on the seeding method of covering up seed with soil is distinguished from those on other two seeding methods. According to this results, the best possible seeding measure to be developed should be mechanical seed spraying with soil.

• Journal of Forest and Environmental Science
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• 제35권1호
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• pp.61-68
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• 2019

The purpose of this study is to evaluate the natural habitat of Hotaria unmunsana Doi, which was first discovered at Mt. Unmun also represents a landscape indicator species for Daegu and Gyeongbuk provinces, and Luciola lateralis Motschulsky, which is the object of experiential activation at festivals in some cities in the region. The spatial range of this study is limited by Daegu City and Gyeongbuk province, and is used to predict the preference of firefly for altitude, slope, direction, shaded relief, riparian buffer zone, river environment, and farmland to analyze the area that best matches the habitat of fireflies. As a result, fireflies are highly influenced by altitude and there may be no large-scale habitats in some areas through the Nakdong and the Baekdu mountain ranges, which occur at high altitude. In most of the cities, we found major habitats around the streams and wetlands. By region, the sites were widely distributed around the cities focused on Nakdong River, and many habitats emerged around the Nakdong River tributary and gentle slopes. In order to preserve and spread the habitat of fireflies, the physical environment as well as their relationship with food chains and symbiotic organisms should be established, and excessive use of pesticides and herbicides in agricultural areas should be avoided.

• 대한원격탐사학회지
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• 제35권1호
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• pp.15-28
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• 2019

By applying the method of SAR interferometry to X-band synthetic aperture radar (SAR) image of COSMO-SkyMed, detailed motion patterns of five glaciers in the Parlung Zangbo River basin, Tibetan Plateau, in January 2010 have been derived. The results indicate that flow patterns are generally constrained by the valley geometry and terrain complexity. The maximum of $123.9ma^{-1}$ is observed on glacier No.1 and the minimum of $39.4ma^{-1}$ is found on glacier No.3. The mean values of five glaciers are between 22.9 and $98.2ma^{-1}$. Glaciers No.1, No.2, No.4 and No.5 exhibit high velocities in their upper sections with big slope and low velocities in the lower sections. A moraine lake accelerates the speed of mass exchange leading to a fast flow at the terminal of glacier No.3. These glaciers generally move along the direction of decreased elevation and present a macroscopic illustration of the motion from the northwest to the southeast. The accuracy of DEM and registration conditions of DEM-simulated terrain phases has certain effects on calculations of glacier flow direction and velocity. The error field is relatively fragmented in areas inconsistent with the main flow line of the glaciers, and the shape and uniformity of glacier are directly related to the continuous distribution of flow velocity errors.

• 한국지형학회지
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• 제26권1호
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• pp.1-14
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• 2019

Large landslide is a type of mass movement that causes drastic landform changesin a short period, and it causes huge human and property damage over a large area. The purpose of this study is to categorize the types and characteristics of large landslides around the Kokomeren River basin, Kyrgyzstan and to discuss the geomorphic development after the large landslides. The topographic analysis about a total of 20 landslides documented collapsed volumes of 0.01 to 1.10 km³, height drops of 180 to 1,770 m, and runout distances of 1,200 to 5,400 m. Rock avalanche and rockslide are identified as major types of large-scale landslides in the study area. Rock avalanches can be divided into P-type, J-type, and S-type based on the features of slope failure and kinematic characteristics of rock debris. Landslide synchronistic landforms such as trimlines, transverse ridges, longitudinal ridges, levees, and hummocks are well developed in the rock avalanche. The pieces of evidence of landslide dam, landslide-dammed lake, and remnant outburst flood deposits are observed in the upstream and downstream where the rockslides occurred. The Ak-Kiol landslide dam is the best example of a geomorphic development due to lake spillover and the large landslides were likely to be triggered by huge paleo-seismic events.