• 한국수자원학회논문집
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• 제40권2호
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• pp.125-134
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• 2007

본 연구의 목적은 치수안정성을 고려하여 새롭게 개발된 식생 호안 공법들의 적용성을 검토하는 것이다. 호안의 적용성은 치수 안전성과 환경성의 두 가지 측면을 통하여 검토되었다. 치수 안정성은 파주시에 위치한 동문천에서의 현장 실험과 수로 실험을 통하여 검토하였으며, 환경성은 동문천 시험 시공 지점에 대한 2년간의 식생 모니터링 결과를 분석하여 검토하였다. 연구 결과 개발된 식생 호안 모두 적절한 치수 안전성과 우수한 녹화능력이 있는 것으로 나타났다. 실험 결과 분석을 통하여 평균 유속과 평균 소류력에 대하여 개별 호안의 최대 적용 범위를 제시하였다.

• 자원리싸이클링
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• 제25권1호
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• pp.24-30
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• 2016

노트북 실장인쇄회로기판(Printed Circuit Board Assembly, PCBA)으로부터 탄탈럼을 회수하기 위한 선별실험을 실시하였다. 우선 노트북 실장인쇄회로기판에 실장된 전자부품(Electronic Components, ECs)을 자체개발한 실험장치를 이용하여 기판으로부터 분리하였다. 분리된 전자부품을 체분리하여 -6.35+2.80 mm구간에서 전체 탄탈럼 캐퍼시터의 약 93.2 wt.%를 회수할 수 있었다. 회수된 탄탈럼 캐퍼시터를 해머밀로 분쇄 후, 자력선별기를 통해 자력세기 300 가우스에서 분쇄물 중의 전극을 제거하였다. 전극이 제거된 자력선별 산물을 대상으로 넬슨 선별기(Knelson concentrator)를 이용한 선별 실험 결과 Bowl의 회전수 200 rpm, 유동층수 유량 7 L/min에서 76.9%의 최대 선별효율을 보였으며, 이때 품위 및 회수율은 각각 약 81.1%, 약 78.8%를 나타내었다.

• Water Engineering Research
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• 제2권2호
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• pp.75-87
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• 2001

A new moving boundary technique for leap-frog finite difference numerical mode is proposed for the resonable simulation of coastal inundation over discontinuous topography. The new scheme improves the moving boundary technique developed by Imamura(1996). The present scheme is tested using the analytical solution of Thacker(1981) for the case of free oscillation with moving boundary in a parabolic bowl. Finally, a numerical simulation is conducted for the flooding over a tidal barrier constructed on a simple concave geometry. A general feature of inundation over a discontinuous topography is well described by the numerical model.

• Environmental Analysis Health and Toxicology
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• 제30권sup호
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• pp.2.1-2.11
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• 2015

Objectives This study presents a methodology that enables a quantitative assessment of green chemistry technologies. Methods The study carries out a quantitative evaluation of a particular case of material reutilization by calculating the level of "greenness" i.e., the level of compliance with the principles of green chemistry that was achieved by implementing a green chemistry technology. Results The results indicate that the greenness level was enhanced by 42% compared to the pre-improvement level, thus demonstrating the economic feasibility of green chemistry. Conclusions The assessment technique established in this study will serve as a useful reference for setting the direction of industry-level and government-level technological R&D and for evaluating newly developed technologies, which can greatly contribute toward gaining a competitive advantage in the global market.

• 한국환경복원기술학회지
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• 제21권1호
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• pp.55-71
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• 2018

To improve the ecological function of urban areas, the guideline for applying the Biotope Area Ratio to the Environmental Impact Assessment (EIA) was developed in 2005 and modified in the July, 2017. This study investigates whether the guideline has been actually practiced in the real world by searching reports including 648 cases of the Strategic Environmental Impact Assessment (SEIA) and 471 cases of the EIA. The results show that the 38% of SEIA and the 43% of EIA include sections about Biotope Area Ratio, and the 15% of SEIA and the 25 % of EIA are satisfied the threshold of the Biotope Area Ratio suggested by the guideline. The statistical analysis results show that this low level of practice was not improved through the modification of the guideline in 2017. This is because the guideline is forcibleness, its explanation is unclear, and stockholders' understanding of it lacks. In addition, lack of tracking management on SEIA and EIA also contributes to the low level of practice of the guideline. To promote the practice, the efforts to legislate and publicize the guideline are required.

• 한국환경과학회지
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• 제19권2호
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• pp.149-155
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• 2010

Rainfalls would increase the discharges or stages of tributary channels in natural watersheds, which in turn augment the magnitude of main stream stages. Rising of water surface elevation in main streams can affect and damage the human activities because of the possibilities of the breakdown or overflow of the embankment. Therefore it is necessary to establish the structural or non-structural alternatives for the sake of prevention or treatment of those disasters. Many mathematical models to analyze the flood flows in natural watercourses have been proposed as the non-structural alternatives so far. In this study one of the such models, FLDWAV developed by NWS(National weather Service), is applied to the downstream reach of Nakdong river. Model calibration is performed on various Manning's roughness coefficients at the gauging stations. The simulation results are compared well with hydrological estimations of flood discharges considering the effects of multipurpose dams upstream of control points.

• 한국항해항만학회지
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• 제36권9호
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• pp.741-751
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• 2012

This article analyzes the interdependency between nonrenewable marine sand resources and renewable fishery resources by the developed dynamic bioeconomic model. The developed bioeconomic model is applied to a case study of efficient sustainable management for marine sand mining, which adversely affects a valuable blue crab fishery and its habitat in Korea. The socially-efficient extraction plan for marine sand and the time-variant environmental external costs to society in terms of diminished harvest rate of blue crab are determined. To take into account long-term effects from destroyed fishery habitat, a Beverton-Holt age structure model is integrated into the bioeconomic model. The illustrative results reveal that the efficient sand extraction plan is dynamically constrained by the stock size of the blue crab fishery over time. Thus, the dynamic environmental external cost is more realistic resource policy option than the classical fixed external cost for determining socially optimal extraction plans. Additionally, the economic value of bottom habitat, which supports the on- and off-site commercial blue crab fishery is estimated. The empirical results are interpreted with emphasis on guidelines for management policy for marine sand mining.

• 한국수자원학회논문집
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• 제38권9호
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• pp.779-790
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• 2005

지속가능한 발전의 개념은 국제적으로 개발과 환경의 보전의 논쟁의 중심이 되고 있으며, 수자원 개발과 관리는 이들 논쟁에서 가장 중요한 부분을 차지하고 있다. 지속가능한 발전의 많은 개념이 제시되고 있지만 수자원 분야에서는 그 실행이 미비한 실정이다. 본 연구에서는 지속가능한 수자원개발과 관리에 대한 개념을 정립하고 이를 평가할 수 있는 지표에 대해 알아보았다. 또한 국내실정에 맞는 지표를 개발해 국내 수자원의 지속가능성을 평가하였으며, 국외에서 개발된 지표를 통해 국내 수자원 현황을 평가하였다.

• 한국수자원학회논문집
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• 제34권6호
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• pp.627-640
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• 2001

일반적으로 합성단위도법은 강우-유출기록이 없는 유역의 설계홍수량 산정을 위해 제안되었다. 그러나 국내에서는 아직까지 자료의 부족 등으로 외국에서 개발된 각종 유출모의 모형이 주로 이용되고 있다. 따라서 그 동안 축적된 국내의 강우-유출 자료를 이용하여 국내의 수문특성엥 적합한 유출모형의 개발이 절실한 상황이다. 이를 위해 본 연구에서는 설마천 유역의 2개 지점과 IHP 대표유역인 평강창, 보청천, 위천의 17개 지점에 대해 그 동안 축 (중략) 특성 관련 연구결과를 종합하여 새로운 합성단위도법을 개발하였다. 개발된 합성단위도는 유역특성인자와 단위도치식 치(첨두시간, 첨두유량)와의 다중회귀분석을 통해 유역면적-유로연장-유로경사의 3가지 변수로 구성되는 효 (중략) 전국을 있었다. 따라서 우리나라에서는 아직까지 수계별로 합성단위도를 분리하여 제시하기는 무리라고 보여지 (중략)

• Water Engineering Research
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• 제1권1호
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• pp.39-48
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• 2000

This work was completed in partial fulfillment of an on-going research ot descover the effective management of urban nonpoint sources. The current data was obtained from the area of Shingal, Kyunni-do. The investigation was are predominant soures of storm-runoff load and drainage. As a result of the investigation, the road was found to be most seriously contaminated and a significant potential source deteriorating the quality of streams and lakes in the vicinity of the town. Thus, in could be concluded that an effective and systematic cleaning technique must be developed as soon as possible and be frequently applied to the road.