• 한국초전도ㆍ저온공학회논문지
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• 제20권2호
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• pp.16-19
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• 2018

Comprehensive utilization of zinc smelting iron slag not only solves environmental problems but also creates huge economic benefits. This study was conducted on the enrichment and recovery of ${\alpha}-Fe_2O_3$ from zinc smelting iron slag by superconducting HGMS technology. Several variables such as slurry flow velocity, slag concentration, magnetic field intensity and the amount of dispersing agent were tested in magnetic separation. In the experiments, obtained optimal magnetic separation parameters were 1.60 T of magnetic flux intensity, 600 mL/min of slurry flow velocity of, 15 g/L of slag concentration of, 0.10 g/L of dispersing agent. Under this condition, the content of ${\alpha}-Fe_2O_3$ was increased from 86.22% to 94.39% that can approach the Chinese national standard requirements (A level) of iron oxide red. It was concluded that using superconducting HGMS technology was an effective method for the purification of ${\alpha}-Fe_2O_3$ from zinc smelting iron slag.

• Ecology and Resilient Infrastructure
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• 제6권1호
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• pp.1-11
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• 2019

본 연구는 생태 물길 복원 조성에 따른 어류 군집종에 미치는 영향을 파악하기 위하여 물리 서식처 분석을 수행하였다. 대상 어종은 피라미, 쉬리, 참갈겨니, 돌고기, 줄납자루, 밀어, 묵납자루, 꾸구리, 가는돌고기로 선정하였으며, 총 9개 어종으로 달천 내 서식하는 어류 중 95%를 차지한다. 흐름 분석은 2차원 모형인 River2D 모형을 사용하였으며, 서식처 분석은 서식처 적합도 곡선을 이용하는 서식처 적합도 모형을 사용하였다. 생태 물길 복원은 하도 내 위치한 돌보 철거 및 여울-소 구조 조성과 하상고 및 하폭의 변화를 통하여 조성하였다. 그 결과 생태 물길 복원 조성을 통하여 최적의 환경 생태 유량 조건 ($Q=7.0m^3/s$)에서 총 9종 군집종의 가중가용면적을 약 16% 향상시키는 것으로 나타났다. 이를 통하여 생태 물길 복원 조성이 하천 내 서식하는 다양한 군집종에 대하여 매우 유용한 방법임을 확인할 수 있다.

• Journal of Ecology and Environment
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• 제39권1호
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• pp.43-49
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• 2016

Fishways are constructed to provide longitudinal connectivity of streams or rivers where their flow has been altered by in-stream structures such as dams or weirs. Nature-like fishways have an additional function of providing fish habitats. In the study, we estimated the role of a nature-like fishway (length: 700 m, slope: 1/100) for fish habitat by using two dominant species in the Sangju Weir, Nakdong River, to calculate the optimal ecological flow rate using Physical HABitat SIMulation (PHABSIM). To identify the dominant species that used the fishway, we conducted trap monitoring from August to November 2012 at the fishway exit. The dominant species were Zacco platypus and Opsariichthys uncirostric amurensis with a relative abundance of 62.1% and 35.9%, respectively. Optimal habitat suitability indices (HSIs) for Z. platypus and O. u. amurensis were calculated as 0.6-0.8 m/s (water velocity) and 0.2-0.4 m (water depth), and 0.5-0.7 m/s (water velocity) and 0.1-0.3 m (water depth), respectively. The optimal ecological flow rates (OEFs) for Z. platypus and O. u. amurensis were 1.6 and 1.7 cubic meter per second (CMS), respectively. The results of the study can be used in a management plan to increase the habitat function of nature-like fishways in the Sangju Weir. This methodology can be utilized as an appropriate tool that can determine the habitat function of all nature-like fishways.

• 한국환경과학회지
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• 제11권4호
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• pp.309-317
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• 2002

In this study, water protection reservoir is selected as the target which is located at the estuary of Taehwa river to analyze and examine the effects of hydraulic structure on river environment. This study examined the water quality variation characteristics among many effects of hydraulic structure on river environment before and after removal of the sediment protection reservoir when low flow is yielded. This study aims at the definition of factors which cause the change of ecological environment of river due to the effects of the sediment protection reservoir, and the proposal of the direction of environmental friendly river space development through the comparison of stream variation conditions(depth, velocity, and etc.) and riverbed variation characteristics with ecological depth condition of Taehwa-river's channel for each representative species of fish and examination those. Firstly, from the examination result of water quality when low flow is yielded before and after removal of the sediment protection reservoir for problems about water quality of river due to flow amount decrease in river, it is found that DO decreases about 0.78~0.86ppm at the lower stream of Myeongchon-gyo, and BOD decreases about 0.06~0.24ppm from right upper stream to the direction of estuary when the sediment protection reservoir is removed. It is known from the above that there is some improvement of water quality from the lower stream of Taehwa-gyo to the estuary in case of removal the sediment protection reservoir. Nextly, it is thought that the effects on ecosystem due to water depth and draw down in channel is not serious on the basis of the examination of water quality analysis result according to removal of sediment protection reservoir and hydraulic depths for reservation of ecosystem, these are 10~40cm for breeding season, 10~50cm for fry period, and 10~100cm for adult period of the representative species of fish in Korea.

• 환경생물
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• 제26권3호
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• pp.203-213
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• 2008

Benthic macro invertebrate communities were collected at six different sampling sites in the Musucheon stream in Korea from July 2006 to July 2007, and ecological exergy values were calculated based on five different functional feeding groups (collector-gatherer, collector-filterer, predator, scrapper, and shredder) of benthic macro invertebrates. Each sampling site was categorized to three stream types (perennial, intermittent and drought) based on the water flow condition. Exergy values were low at all study sites right after a heavy rain and relatively higher in the perennial stream type than in the intermittent or the drought stream type. Self-Organizing Map (SOM), unsupervised artificial neural network, was implemented to pattern spatial and temporal dynamics of ecological exergy of the study sites. SOM classified samples into four clusters. The classification reflected the effects of floods and droughts on benthic macroinvertebrate communities, and was mainly related with the stream types of the sampling sites. Exergy values of each functional feeding group also responded differently according to the different stream types. Finally, the results showed that exergy is an effective ecological indicator, and patterning changes of exergy using SOM is an effective way to evaluate target ecosystems.

• 한국해양환경ㆍ에너지학회지
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• 제20권1호
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• pp.12-17
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• 2017

해양생태계 복원 대상지 수요조사 결과를 대상지역으로 연안복원사업의 생태적 목표 및 성공 판단기준 항목을 설정하였다. 생태적 목표와 성공 판단기준 설정을 통하여 연안복원 사업이 기술공학적 목표와 친수공간 조성이라는 사회적 목표에 따라 단순이 반복되는 일회성 사업으로 그치는 현상을 억제할 수 있다. 또한, 전국 연안이 자연생태계에 의존하여 자연설계(Self-design)되고 스스로 조성(Self-organization)될 수 있는 생태공학적 접근법이라는 점에서 연안 생태계의 지속적인 이용이 가능하게 될 것이다. 생태적 목표는 연안 생태계의 유형별로 생물종 다양성, 물흐름 조절, 정화능력 개선, 침식 방지와 서식처 제공으로 설정하였다. 성공기준 항목은 갯벌 조사지침의 조사항목 중에서 생태적 목표별로 대상 생물의 출현종수와 군집특성, 그리고 수리, 수질, 지질 환경의 해당 항목으로 설정하였다.

• 한국조경학회지
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• 제32권2호
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• pp.102-119
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• 2004

This study investigates the relation between the location of a habitat and the ecological connections according to the habitat type in the riparian zone at the Bokha stream. Stream habitat is classified into nine types for the aquatic insects and fish. For vegetation and birds, habitat is classified into five types of medium-scale streams, including both physical and chemical streams are analyzed accordingly. The major results of this study are as follows: 1) A pool connected to the main stream has a certain water depth (about 80 cm) and is disturbed at least 5 to 6 times a year. Although the pool has a somewhat bad water quality, it provides a habitat for various types of young fish. 2) A meander riffle is about 15 cm deep, the flow velocity in the region is about 75 cm/s. This region does not have large structures to which aquatic insects can attach, so it cannot be used as a spawning ground. 3) A rock type pool is about 60 cm deep, the flow velocity in the meander riffle is about 25 cm/s. In this region, many aquatic insects attached to large structures appear. Due to various riparian vegetation, the rock type pool is used as a habitat for aquatic insects. 4) A pool which is only connected to the main stream during floods has a bad water quality. Despite of its relatively small size, it has a high population density of aquatic insects. faculty.

• 대한토목학회논문집
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• 제39권1호
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• pp.33-44
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• 2019

최근 기후변화 현실화로 강우 발생 시기와 패턴이 변화하면서 유역에 따라 유황이 변화하고 있는 실정이다. 이로 인한 하천 유황의 장기적 변화는 수중생태계의 구조와 기능에 커다란 변화를 야기한다. 하지만 국내에서는 기후변화와의 연계성은 물론, 유량변화와 생태학적 특성을 포함한 수생태계 관점에서의 분석은 대부분 이루어지지 않고 있다. 따라서 본 연구에서는 기후변화로 인한 현재-미래의 유황 변화가 만경강 하도와 홍수터 영역에서 감돌고기의 서식환경에 미치는 영향을 정량적으로 평가하였다. 그 결과, 현재보다 미래에 홍수와 가뭄 등 극한 수문 조건이 심화됨을 확인하였고, 특히 크기, 빈도, 지속시간, 시기와 변화율 등을 비교 분석함으로써 유황 특성의 변화를 명확히 파악하였다. 그리고 유황 특성과 물리서식처 해석을 연계함으로써 기후변화로 인해 미래 생태환경 변동에 대한 위험성이 크게 증대될 것이라는 결과 제시가 가능하였다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.106-106
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• 2015

The information of flow regimes continues to be norm in water resource and watershed management, in that stream flow regime is a crucial factor influencing water quality, geomorphology, and the community structure of stream biota. The objectives of this study were to estimate Korean stream flows from landscape variables, classify stream flow gages using hydraulic characteristics, and then apply these methods to ungaged biological monitoring sites for effective ecological assessment. Here I used a linear modeling approach (MLR, PCA, and PCR) to describe and predict seasonal flow statistics from landscape variables. MLR models were successfully built for a range of exceedance discharges and time frames (annual, January, May, July, and October), and these models explained a high degree of the observed variation with r squares ranging from 0.555 (Q95 in January) to 0.899 (Q05 in July). In validation testing, predicted and observed exceedance discharges were all significantly correlated (p<0.01) and for most models no significant difference was found between predicted and observed values (Paired samples T-test; p>0.05). I classified Korean stream flow regimes with respect to hydraulic and hydrologic regime into four categories: flashier and higher-powered (F-HP), flashier and lower-powered (F-LP), more stable and higher-powered (S-HP), and more stable and lower-powered (S-LP). These four categories of Korean streams were related to with the characteristics of environmental variables, such as catchment size, site slope, stream order, and land use patterns. I then applied the models at 684 ungaged biological sampling sites used in the National Aquatic Ecological Monitoring Program in order to classify them with respect to basic hydrologic characteristics and similarity to the government's array of hydrologic gauging stations. Flashier-lower powered sites appeared to be relatively over-represented and more stable-higher powered sites under-represented in the bioassessment data sets.

• 대한토목학회논문집
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• 제26권2B호
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• pp.153-160
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• 2006

본 연구에서는 한강 수계의 주요 지천별 어류 서식환경을 고려한 필요유량을 산정하기 위하여 어류서식처 환경평가방법의 한가지인 유지유량 증분 방법론(IFIM)을 적용하였으며 어류의 미시서식처 조건을 만족하는 적정 필요유량을 산정하기 위하여 물리적 서식처모의 시스템(PHABSIM)를 이용하였고, 어류의 거시서식처 조건을 만족하는 적정 필요유량을 산정하기 위해서 QUAL2E 모형에 의한 수질모의를 시도하였다. 물리적 서식처모의 시스템을 한강수계에 적용하기 위하여 구간별 대표 어종의 성장단계별 서식처 적합도기준(Habitat Suitability Criteria)을 현장조사에 의한 어류채집을 통하여 수심 및 유속에 대하여 각각 작성하였다. 유지유량 증분 방법론을 한강수계에 적용하는 과정에서 산정결과에 대한 토의와 함께 적용상의 문제점에 대하여 분석하였다. 본 연구결과는 향후 한강수계의 하천유지유량을 결정하는데 중요한 지표로 활용될 수 있을 것으로 판단된다.