• Korean Journal of Ecology and Environment
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• v.42 no.1
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• pp.19-25
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• 2009

The effects of artificial floating island on the changes in phytoplankton and zooplankton community structure were investigated monthly from September 2006 to May 2007 in Shingu reservoir. The total cell number of phytoplankton under the artificial floating island was three times less than those of control (without artificial floating island). The dominant species of phytoplankton were Lyngbya sp. on September, Cryptomonas sp. from October to January, Aulacoseira granulata on February and Oscillatoria sp. from March to May at lake water. Cyanophyta was dominated from February to March at lake water but it was dominated from March at artificial floating island area. The total individual number, species number of zooplankton and species diversity of phytoplankton and zooplankton under the artificial floating island were higher than those of lake water.

• Korean Journal of Ecology and Environment
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• v.40 no.3
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• pp.395-402
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• 2007

Concentrative samplings of 35 times on standing crops of phytoplankton and physicochemical factors were conducted at five sites over Seongsu Bridge to Seongsan Bridge in lower parts of the Ban River from January to December 2006. Over the study, all physicochemical factors showed no large differences among the sampling sites except station 2 having high concentrations of BOD, TN, and TP. Heavy rain also cause these concentrations to decrease. The phytoplankton species and abundance (88 taxa and $1{\sim}41$,104 cells $mL^{-1}$) were varied according to the season, and sharply decreased during heavy rains. In particular, cyanobacteria dominated the phytoplankton community during dry seasons, while green algae and diatom dominated during the rainy seasons. However, after the termination of rain, high water temperatures over $20^{\circ}C$ and low N/P ratios $(9.4{\sim}18.9)$ evoked the cyanobacterial bloom. These results indicate that although the heavy rain (huge outflows of Paltang Dam) temporarily diluted the nutrient level and effected the cyanobacterial bloom in the lower parts of the Han River, cyanobacterial abundance was recovered by the high temperature and low N/P ratio as the rainfall discontinued.

• Journal of the Korean Society for information Management
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• v.41 no.1
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• pp.411-438
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• 2024

This study aims to identify and comprehensively view health information-related research trends using a bibliometric analysis. To this end, 1,193 papers from 2002 to 2023 related to "health information" were collected through the Korea Citation Index (KCI) database and analyzed in diverse aspects: research trends by period, academic fields, intellectual structure, and keyword changes. Results indicated that the number of papers related to health information continued to increase and has been decreasing since 2021. The main academic fields of health information-related research included "biomedical engineering," "preventive medicine/occupational environmental medicine," "law," "nursing," "library and information science," and "interdisciplinary research." Moreover, a co-word analysis was performed to understand the intellectual structure of research related to health information. As a result of applying the parallel nearest neighbor clustering (PNNC) algorithm to identify the structure and cluster of the derived network, four clusters and 17 subgroups belonging to them could be identified, centering on two conglomerates: "medical engineering perspective on health information" and "social science perspective on health information." An inflection point analysis was attempted to track the timing of change in the academic field and keywords, and common changes were observed between 2010 and 2011. Finally, a strategy diagram was derived through the average publication year and word frequency, and high-frequency keywords were presented by dividing them into "promising," "growth," and "mature." Unlike previous studies that mainly focused on content analysis, this study is meaningful in that it viewed the research area related to health information from an integrated perspective using various bibliometric methods.

• Journal of Astronomy and Space Sciences
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• v.23 no.2
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• pp.135-142
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• 2006

The extension of sunspot number series and auroral observations backward in time is of considerable interest for dynamo theory, solar activity and climate research. It was known that the Maunder minimum corresponded to a unusual cold so called little ice age in Europe and the appearance of sunspot had a close relation to the occurrence of aurora. Therefore we have examined ancient records of sunspots and aurorae with indirect solar proxies during this period and have studied for the features and peculiarities of solar activity with the relation of the climate variation.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.1
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• pp.47-58
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• 2000

Geographical distribution of salps was elucidated in the South Sea of Korea with focusing on the April and June, 1997 when swarm of salps occurred. We also discussed on its distributional pattern in relation to environment conditions and its impact on marine ecosystem with emphasizing on trophodynamics. Salps were abundantly distributed in the south-eastern area of Cheju Island where is closely associated with the Tsushima Warm Current. In April and June, 1997, surface water temperature was $2{\sim}5^{\circ}C$ higher than the average over 1961-1998, while surface water salinity was lower. Chlorophyll-a concentration, density of copepods and catches of mackerel sharply decreased in April and June, 1997. These results suggest that the swarm of salps was due to not only transportation by strong Tsushima Warm Current but also supply of abundant foods. Low densities of copepods may be related to the presence of swarm of salps because of food competition between them. The fact that the catches of mackerel were very low in April and May, 1997 suggests that the trophodynamics between salps and copepods also influence the fish resources.

• The Korean Journal of Ecology
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• v.26 no.4
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• pp.181-188
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• 2003

Frequencies of each size class, annual change of tuber state and above ground/belowground rate in sect. Pes-gallinaceua group of Corydalis (Fumariaceae) were studied to clarify spring ephemeral´s growth characteristics from 1999 to 2000 in Namhansansung area. Shoot grew from the tuber corresponding with soil thawing in the early growth season, and the deeper tuber was located in soil, the later shoot germinated. Shoot appeared in middle March and died early in May, and the period of total growth season was 45 days. Frequencies were 40% (in total dry weight) or 53% (in tuber´ dry weight) in the smallest size class, and 93% (in total dry weight) or 96% (in tuber´ dry weight) below medium size, therefore, almost all of plants were small. Specific gravity of tuber (SGT) gradually decreased from late growth season to the time that leaf unfolded in next year. At this time, the value of SGT was 0.14. Thereafter, SGT increased to 0.42 at withering time of aboveground part. During growth season, the SGT of flowering plants was lower than that of non-flowering plants. And SGT difference between flowering plants and non-flowering plants was significant at 1% level. In the late growth season, SGT decreased along the increase of tuber volume. The tuber volume roughly increased along the leaf area but there was no a conspicuous trend. Shoot/tuber rate had nothing to do with tuber volume. SGT decreased and leaf area increased along the tuber dry weight, and tendencies of increase or decrease were conspicuous. Therefore, the smaller the plants were, the larger organic matter accumulated in tuber during a growth season. Shoot/tuber rates were various along each plant.

• The Optical Journal
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• s.119
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• pp.35-37
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• 2009

지난 수년 간 국내 광학산업은 눈부신 발전을 했다. 디지털카메라, 핸드폰카메라, 정보저장기기, 복사기와 같은 전자제품 시장의 성장, 평판디스플레이의 도약, LED 조명의 출현, 매 순간이 숨 가쁜 변화와 팽창의 연속이었다. 작년에 시작된 미국발 금융위기가 전 세계 신용경색, 실물경제 침체로 이어지면서 국내 광학산업에 먹구름이 드리워지고 위기감이 고조되고 있다. 본 원고는 해외 광학회사, 연구기관들과 협력하면서 고찰한 내용에 필자의 의견을 덧붙인 것이다. 이제는 국내회사들이 지속적으로 성장하기 위해서 세계 시장을 대상으로 '그레이트 게임'을 할 시기이다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.133-134
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• 2002

제주해협에 접해 있는 한국남해연안역은 대체로 50m미만의 천해로써 제주해협에 비해 계절별로 하계에 저온ㆍ고염분수, 동계에 저온ㆍ저염분수가 출현해 해협내 연중 전선을 형성하는 해역으로서 특히, 한국 남해연안역에 위치해 있는 추자도 주변해역은 지형적 특성상 대마난류수, 한국 남해연안수와 중국대륙연안수, 황해저층냉수 등 이러한 이질수괴들이 시기와 계절별로 서로 상접하여 복잡한 해황을 형성하는 해역이다(Rho, 1985, 최, 1989, 김ㆍ노, 1994, Yoon, 1986, Rhoㆍ평야, 1983). (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.35-36
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• 2002

제주도 근해는 대마난류, 황해 난류, 황해 냉수, 한국 남ㆍ서해연안수, 중국대륙 연안수 등이 출현하여 이질 수괴들이 시기와 계절별로 복잡한 해황을 형성하여 오징어, 갈치, 고등어, 전갱이, 방어, 삼치 등을 어획하는 좋은 어장을 이루고 있다. 우리나라 연안 해역에서는 오징어를 걸이, 대낚시, 전기식설낚시, 연결식낚시, 로울러낚시, 자동조획기 등으로 어획하고 있으나, 이들은 원줄에 오징어 낚시가 수직식으로 연결되어 있다. (중략)

• Proceedings of the Korean Society of Crop Science Conference
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• 1995.10a
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• pp.54-55
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• 1995