• 한국잔디학회:학술대회논문집
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• 한국잔디학회 2005년도 학술대회지
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• pp.26-27
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• 2005

• 한국동물학회:학술대회논문집
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• 한국동물학회 2003년도 한국생물과학협회 학술발표대회
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• pp.33-33
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• 2003

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• 자원ㆍ환경경제연구
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• 제14권4호
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• pp.867-891
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• 2005

댐건설 관련 합리적 의사결정을 위해서는 댐건설로 인해 발생하는 편익과 비용을 적절히 평가하여 비교하는 것이 필요하다. 댐건설 관련 많은 비시장적 편익과 비용이 현재로서는 의사결정에 적절히 반영되지 못하고 있는데, 본고는 비시장적 편익 가운데서도 댐이 건설될 경우 생성되는 인공호수가 제공하는 휴양가치를 분석한다. 방문객수가 많은 10개 댐호수에서 963명의 방문객을 조사하여 각 방문객이 이용 가능한 댐호수 가운데 한 군데를 선택하는 행위를 분석하였고, 이들의 선택행위를 혼합로짓모형(mixed logit model) 흑은 확률파라미터 로짓모형(random parameters logit model)을 추정하여 분석하였다. 모형추정을 통해 호수의 저수량, 낚시행위의 가능 여부, 유람선 이용 가능 여부, 수변 음식점이 이용 가능한지의 여부 등 댐호수의 특성별 경제적 가치와 호수별 전체 휴양가치의 분포를 도출하였다.

• Journal of Species Research
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• 제6권2호
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• pp.163-170
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• 2017

As a part of the research program 'Survey of freshwater organisms and specimen collection', freshwater samples were collected from Lakes Soyang and Chungju in 2016. Hundreds of bacterial strains were isolated from the samples and were identified based on 16S rRNA gene sequences. Among the bacterial isolates, strains showing higher than 98.7% sequence similarity with validly published bacterial species not reported in Korea were selected as unrecorded bacterial species. Based on 16S rRNA gene sequence similarity, 17 strains were identified as unrecorded bacterial species in Korea. The 17 bacterial strains were phylogenetically diverse and belonged to four phyla, seven classes, 13 orders, 14 families, and 16 genera. At generic level, the unreported species were affiliated with Caulobacter, Paracoccus, and Mesorhizobium of the class Alphaproteobacteria, Deefgea, Undibacterium, Chitinimonas, Inhella, and Sphaerotilus of the class Betaproteobacteria, Vibrio and Cellvibrio of the class Gammaproteobacteria, Sanguibacter and Clavibacter of the phylum Actinobacteria, Lactococcus of the phylum Firmicutes, Deinococcus of the class Deinococci, and Chryseobacterium and Flavobacterium of the phylum Bacteroidetes. The unreported species were further characterized by examining Gram reaction, colony and cell morphology, biochemical properties, and phylogenetic position. The detailed description of the 17 unreported species are also provided.

• 한국유체기계학회 논문집
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• 제17권3호
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• pp.52-58
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• 2014

The development of efficient systems for water quality improvement for water sources such as lakes, dams and reservoirs has become a necessity to provide not only a cleaner and safer water to the urban society, but also to provide a cleaner and safer environment for the aquatic organisms living in lakes, dams and reservoirs. This study concentrates on the outlet design and internal flow analysis of an axial flow pump used in a floating type water treatment system completely powered by renewable energy source. The treatment system is designed to raise water from depths of about 3~5m up to the water surface where it is naturally mixed with air as it is released back to the reservoir. The outlet of a typical axial flow pump is modified to suit the floating type water mixer. The performance of the axial flow pump is studied by investigating the internal flow of the system. Results show that the change in outlet shape does not alter the performance of the original pump at the maximum efficiency point as long as the cross sectional area of inlet is the same as the outlet. The axial pump for floating type water treatment system has good cavitation performance in the whole flow passage.

• 대한토목학회논문집
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• 제13권2호
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• pp.287-293
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• 1993

본 연구에서는 하천이나 호수의 저변부에 퇴적되어 있는 저질토로 인한 산소요구량 (SOD)을 효율적으로 산정할 수 있는 실험방법과 추정방법을 제안하였다. 이 방법을 청주시 인근 석남천 상류지점에 적용한 결과 저질토의 산소요구로 인하여 수체내 용존산소의 농도는 용존산소의 농도에 대하여 1 차 반응의 형태로 감소하였다. 본 연구에서 제안한 방법으로 추정한 SOD는 2.48 - 5.33 g $O_2/(m^2{\cdot}day)$의 범위로서 통상 오염된 하천에서의 SOD의 범위(1.5 - 10.0 g $O_2/(m^2{\cdot}day)$ 이내 이었고, 실험방법 및 추정방법 또한 비교적 단순하고 용이하여 현장에서 활용할 수 있음이 규명되었다.

• 대한화학회지
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• 제42권1호
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• pp.51-56
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• 1998

남조류 독성물질인 Microcystins은 자연계에 매우 미량 존재하기 때문에 이를 분리 및 정제하기가 쉽지 않다. 본 연구에서는 자연계에 존재하는 남조류 동결건조시료로부터 Microcystin RR과 LR을 분리 및 정제하는 새로운 방법을 개발하였다. 약 7.5g의 실리카겔을 정지상으로 사용하고 혼합용액인 ethyl acetate: iso-propanol:water(30: 45: 25)을 이동상으로 사용하는 open column system으로 시료를 전개한후 용액을 3mL간격으로 받아냈다. 받아낸 용액중의 Microcystin RR과 LR은 TLC와 HPLC(high performance Liquid Chromatography)를 이용하여 확인한 후 농축, 정제하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.173-176
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• 2008

Lake studies play an important role in water management, ecology, and other environmental issues. Typically, monitoring lake levels is the first step on the lake studies. However, for the Prairie Pothole Region (PPR) of North America having millions of small lakes and potholes, on-site measurement for lake levels is almost impossible with the conventional gage stations. Therefore, we employed Geographic Information System (GIS) and remote sensing approach with the Shuttle Radar Topography Mission data to extract lake levels. Several image processing techniques were used to extract lake levels for January, 2000 as a one-time snapshot which will be useful in historic lake level reconstruction. This study is associated with other remote sensing datasets such as Landsat imagery and Digital Orthophoto Quadrangle (DOQ). In this research, firstly, image processing techniques like FFT filtering, Lee-sigma, masking with Canny Edge Detector, and contouring were tested for lake level estimation. The semi-automated contouring technique was developed to accomplish the bulk processing for large amount of lakes in this region. Also, effectiveness of each method for bulk processing was evaluated.

• 환경영향평가
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• 제18권6호
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• pp.393-399
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• 2009

The water of rivers and lakes are affecting by point and nonpoint source pollutions. The point source pollution can be controlled by establishing the treatment plants. However, nonpoint source pollution by various human activities is not easy to be controlled because it is difficult to determine the exits of the water flow and have many exit points. Due to contribution of nonpoint source pollution, the achievement ratio of water quality in rivers and lakes is not high. TMDL is the outstanding water quality control policy because all of the pollutant loadings from the watershed area are counting on the input loads. Our aqua-ecosystem has self-purification process by biological, physical and ecological processes. The self-purification process can remove the pollutant load from background concentrations. Usually forest area is main source of background concentrations. In Korea, about 70% of the national boundary area consists of mountains. This study is conducting as part of long-term monitoring to determine the Event Mean Concentration during a storm. The monitoring was performed on a broad-leaved tree area.

• 한국물환경학회지
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• 제29권1호
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• pp.7-18
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• 2013

We compared the structure of fish community and condition of major fish species in Lake Chungpyung and Lake Paldang, which are relatively shallow, meso-eutrophic, cascading dam reservoirs on the North Han River. Two lakes have wide littoral zone in the lakeside providing similarly good habitat for fishes, whereas fishery and water recreational activities such as motorboating, water skiing are allowed in Lake Chungpyung but are prohibited in Lake Paldang. The average lengths of large size fishes in Lake Chungpyung are shorter than those of same species in Lake Paldang, resulting in the slight distortion of generation distribution of those species in Lake Chungpyung, possibly owing to the active fishery such as fixed shore net fishing, gill net fishing and angling. Meanwhile the condition of fishes represented by the length-weight relationship of fish species did not show the significant differences between two lakes and showed normal condition. To evaluate the impact of physical disturbance such as loud noise and turbulent wave from water recreational activities to fishes precisely, further studies including physiological responses to stress an spawing activity should be needed.