• Korean Journal of Environmental Biology
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• v.19 no.4
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• pp.239-247
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• 2001

The Herbal Vegetation on Running Waterside in the Main Stream of Genmho River, Daegu and Gyeongsanbuk-do, Korea was investigated by the methodology from June to August of 1994 and analyzed distribution characteristics of vegetation that was related Water Environment. The vegetation is divided into 6 communities of Persicaria sieboldi-Persicaria hydropiper community, Persicaria thunbergii community, Impatiens textori community, Zizania latifoloa community, Phragmites communis community and Echinochloa crus-galli var. oryzicola community. A BOD and COD that indicate degree of contamination in water were showed 0.9 ppm and 1.6 ppm at upstream and 15.9 ppm and 24.8 ppm at downstream, respectively. The distribution patterns of vegetation have dominated by Impatiens textoricommunity in the upstream, by Persicaria sieboldi-Persicaria hydropiper community from upstream to mid-upstream, by Persicaria thunbergii community from upstream to midstream, by Zizania latifoloa community from nidstream to mid-downstream and by Phragmites communis community and Echinochloa crus-galli var. oryzicola community from mid-downstream to downstream. Especially, I suggested that Persicaria sieboldi-Persicaria hydropiper community and Persicaria thunbergii community will use as biotic indicator in water environment.

• Journal of the Korean Geotechnical Society
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• v.27 no.6
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• pp.49-61
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• 2011

This paper presents the applicability of rheological models for describing fine-laden debris flows and analyzes the flow characteristics as a function of grain size. Two types of soil samples were used: (1) clayey soils - Mediterranean Sea clays and (2) silty soils - iron ore tailings from Newfoundland, Canada. Clayey soil samples show a typical shear thinning behavior but silty soil samples exhibit the transition from shear thinning to the Bingham fluid as shear rate is increased. It may be due to the fact that the determination of yield stress and plastic viscosity is strongly dependent upon interstructrual interaction and strength evolution between soil particles. So grain size effect produces different flow curves. For modeling debris flows that are mainly composed of fine-grained sediments (<0.075 mm), we need the yield stress and plastic viscosity to mimic the flow patterns like shape of deposition, thickness, length of debris flow, and so on. These values correlate with the liquidity index. Thus one can estimate the debris flow mobility if one can measure the physical properties.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.150-150
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• 2015

최근 하천의 수위조절 기능을 수행하는 보 건설이 증대되고 있다. 보는 원활한 용수공급을 위해 필수적인 구조물이지만, 하천 횡단 구조물의 특성상 유사퇴적에 의한 통수단면적 감소, 홍수위험도 증가, 수질악화 등의 문제를 내포하고 있다. 이를 해결하기 위해 유사시 유사배출이 가능하고 수문개도를 통한 통수단면적 조절로 홍수위험도를 감소시킬 수 있는 가동보를 고정보와 병용해서 적용하는 추세이다. 가동보는 수문 운영 방식에 따라 하류의 흐름상태가 다양하게 나타나며, 흐름 상태에 따라 하도 및 구조물에 미치는 영향도 달라진다. 그러나 기존 가동보 및 보 하류 구조물의 설계 시 일반적으로 수문 운영조건을 고려하지 않고, 홍수위 조건을 최악조건으로 고려하는 한계가 있다. 본 연구에서는 3차원 수치모델(FLOW-3D)을 활용하여 가동보의 운영에 따라 발생하는 다양한 흐름조건이 보 하류에 미치는 영향을 검토하고자 한다. 수치모델의 검증을 위해 기존 수행된 수리실험과의 비교를 수행하였고, 홍수위 조건(수문 전문개도) 및 관리수위 조건(수문 일부개도)에서 수치모의를 수행하였다. 보 상류, 직하류, 도수종점에서 발생하는 단면최대유속, 바닥전단 응력, Froude 수 등의 수리특성을 분석하였고, 상하류간 수심차와 수문개도높이의 비와 접근유속과 보 직하류에서 유출되는 유속의 비로 무차원화하여 관계를 분석하였다. 또한 홍수위 조건과 관리수위 조건에서 발생하는 수리특성을 비교함으로써, 보 하류부 구조물 설계 시 반영할 최악조건을 예측하고, 수문운영이 하류부에 미칠 수 있는 영향을 가시적으로 확인할 수 있었다. 향후 상류의 유량조건 및 상하류 수위차에 따른 가동보의 운영조건이 보 하류의 안정성 지표산정에 활용될 수 있기 위해 보다 심도있는 연구 수행이 필요하다.

• Clinical and Experimental Reproductive Medicine
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• v.35 no.4
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• pp.303-308
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• 2008

Purpose: The purpose of this study is to determine the effect of preoperative semen parameters on both seminal improvement and pregnancy rates following varicocelectomy. Methods: This survey was done in 278 patients who underwent microsurgical inguinal varicocelectomy from January 2001 until October 2006. By the total motile sperm counts (TMSC) before operation, the patients were stratified into three groups. Group A (mild oligoasthenospermia) was defined as above 20 million, group B (moderate oligoasthenospermia) was defined as between 5 and 20 million, and group C (severe oligoasthenospermia) was defined as below 5 million. Improvement rates of TMSC and pregnancy rates following varicocelectomy of each groups were compared. Results: The average TMSC of all the patients was 25.75 million before operation and after operation, it was 80.24 million, showing an average increase of 54.49 million (211.6%). To take a look at mean absolute increase (mean relative increase proportion), group A showed 67.90 million (131.2%), group B 62.20 million (482.5%) and group C 26.33 million (1841.2%). The patients with varicocele whose semen parameter is in bad condition show relatively a low mean absolute increase but high mean relative increase proportion. There was no significant difference in natural pregnancy rate among each groups (p=0.119, p=0.059). Conclusions: Even in the varicocele patient whose semen parameter was in bad condition before surgical operation. varicocelectomy could be chosen as the first treatment to male infertility.

• Journal of Internet Computing and Services
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• v.21 no.1
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• pp.201-210
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• 2020

This paper proposes a framework for the battle damage assessment (BDA) of electronic warfare linked to cyber warfare. Thanks to the rapid development of information and communication technology, the importance of cyber warfare and electronic warfare in cyberspace is increasing. Therefore, the BDA for cyber warfare and its associated electronic warfare in cyberspace is an important factor that affects the success or failure of military operations. In this paper, we propose a method to calculate measure of performance and measure of effectiveness by classifying the electronic warfare system into large / medium / small classes according to the type of electronic warfare. By setting up a hypothetical scenario, we show the effectiveness of the proposed framework.

• Asian Journal of Turfgrass Science
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• v.19 no.1
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• pp.47-55
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• 2005

This study was conducted to carry out with the structure of ground-beetles(Coleoptera: Carabidae) community surveyed depending on altitude in Mt. Gabjangsan, Sangju, from August 2004 to October 2004. The 1,439 individuals in 15 species of 4 families were found in the survey. In the monthly taxa diversity, September of 697 individuals and 12 species was higher than August of 102 individuals and 8 species and October of 640 individuals and 5 families. The diversity index and evenness index were the lowest, but richness index was the highest in 800m altitude. The richness index was the highest in 400m altitude and evenness index was the highest in loom altitude. Synuchus cycloderus is a dominant species in 300-800m altitude and Synuchus nitidus is a dominant species in loom altitude. In these results, indicator insects for the evaluation of golf courses environment in mountain area construction were selected as S. cycloderus and S. nitidus.

• The Journal of the Korea Contents Association
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• v.12 no.7
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• pp.138-146
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• 2012

This paper is about a the evaluation method for universal design on AHP method. Evaluation of Universal Design to develop indicators of the seven principles of universal design and the tripod of Design(in Japan) Review of the PPP, and previous studies were chosen with reference to a indicators. Selected variables were analyzed using the AHP technique, Universal Design 7 elements were derived weights. Factor of the most important on universal design is 'Perceptible Information'(0.263), and 'Tolerance for Error'(0.207), 'Simple and Intuitive Use'(0.154), 'Low Physical Effort'(0.143) was in order. 'Size & Space for Approach and Use'(0.108) is then shown to be important, while the 'Equitable Use'(0.087), 'Flexibility in Use'(0.038) was rated relatively low importance. Based on the results reflected a weighted evaluation of universal design checklist is proposed. Process to obtain the weights can be applied to a variety of situations.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.355-355
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• 2022

기후변화에 의한 이상가뭄 발생 등을 대비하기 위한 비상용수 또는 대체수자원으로서의 지하수 개발수요가 증가하는 추세에 따라 기저유량 확보 및 수질 개선 방안을 수립하는 것은 지속가능한 수자원 이용·관리 측면에 있어서 매우 중요하다. 지하수 및 기저유량 확보 및 수질 개선을 위해서는 지표-지하수 통합 관리가 필요하며 이를 기반으로 지하수 및 기저유량 변동에 대한 인과관계 파악 및 구체적인 조사가 필요하다. 따라서 본 연구에서는 지표-지하수에 대한 계절적·시공간적 변동성을 잘 모의할 수 있는 통합 모델을 기반으로 지하수위 변동을 포함한 물수지 분석과 장·단기 유출해석이 정량적으로 분석하고자 하였으며, 평창군 대화면, 만대지구, 신둔천 유역을 대상으로 간벌, BMP, LID를 비롯한 다양한 시나리오에 따른 기저유량 및 수질변화 그리고 오염특성 파악을 수행하였다. 본 연구에서는 지표-지하수 통합 모델링을 위하여 SWAT-MODFLOW 모형을 활용하였으며, 간벌 시나리오의 경우 모형 Source code를 수정하여 간벌의 효과를 모의할 수 있도록 수정하였다. 또한 BMP와 LID의 경우 각 HRU별로 저감시설에 대한 효율 및 매개변수 조정을 통해 효율을 모의하였다. 모형의 입력자료 구축을 위하여 지표 모형의 경우 DEM, 토지이용도, 토양도를 활용하였으며, 지하수 모형의 경우 지하수기초조사자료에 수록된 수리전도도, 비산출율, 비보유율 조사결과를 활용하여 입력자료를 구축하였다. 그 결과 간벌시나리오의 경우 건기시 최소 6.7% 이상의 하천유량, 22.56% 이상의 기저유량, 그리고 0.3 m 이상의 지하수위 확보가 가능한 것으로 나타났다. BMP의 경우 유역면적의 약 7%에 BMP가 설치된 것으로 나타났으며, 이에 따른 하천 말단 SS저감효율은 6.7%로 나타났으나 유량에서는 큰 차이를 나타내지 못하였다. 마지막으로 LID시나리오의 경우 적용 소유역의 강우시 평균유량이 약 29% 감소하였으며 건기시 평균 기저유량이 약 44%이상, 평균 BFI는 약 0.13 증가한 것으로 나타났다.

• Journal of the Korean Regional Science Association
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• v.40 no.2
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• pp.57-73
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• 2024

The purpose of this study is to establish the central hierarchy and urban spatial structure of Daejeon in 2040 using differentiated analysis indicators. In order to establish a central hierarchy in the future urban space of Daejeon City, three indicators were derived: population density, use of buildings (commercial, office, residential, etc.) and traffic volume data(KTDB). The results of analyzing the center hierarchy using indicators are as follows. First, the primary centers responsible for urban (core) functions are set in three areas, including Dunsan downtown, the original downtown (Daejeon Station area, designated as a special urban convergence zone), and Doan New Town, and the secondary centers corresponding to sub-city centers (regional bases). was set at 9, 10 tertiary centers corresponding to regional centers (living area centers), and a center hierarchy was established with 5 new specialized bases. Second, new secondary and tertiary centers emerged that were different from the center hierarchy in the 2030 Daejeon Urban Basic Plan. The three indicators used in this study yielded meaningful results in establishing urban spatial structure and central hierarchy that can secure urban competitiveness.

• The Journal of Engineering Geology
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• v.22 no.3
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• pp.283-291
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• 2012

Various studies regarding the prediction of landslides are underway internationally. Research into disaster prevention with regard to debris flows is a particular focus of research because this type of landslide can cause enormous damage over a short period. The objective of this study is to determine the hazard susceptibility of debris flow via predictions of surface water concentrations based on the concept that a debris flow is similar to a surface water flow, as it is influenced by mountain topography. This study considered urban areas affected by large debris flows or landslides. Digital mapping (including the slope and upslope contributing areas) and the wetness index were used to determine the relevant topographic factors and the hydrology of the area. We determined the hazard susceptibility of debris flow by predicting the surface water concentration based on the topography of the surrounding mountainous terrain. Results obtained using the distinct element method were used to derive a correlation equation between the weight and the impact force of the debris flow. We consider that in using a correlation equation, this method could assist in the effective installation of debris-flow-prevention structures.