• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.371-371
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• 2010

탄소나노튜브(CNT)는 기계적인 특성이 뛰어나며, 화학적으로 안정하고, 전기적으로 도체 및 반도체성을 가지고 있을 뿐만이 아니라 직경이 최소 1nm 수준으로 종횡비 및 비표면적이 매우 큰 특성을 가지고 있다. CNT는 투명전극, 유연성 디스플레이, 전자종이 분야 등 투명 전극 응용 분야에서 ITO 대체 신소재로 각광을 받고 있다. 본 발표에서는 SWCNT 전도막의 특성을 향상시키기 위해 PET 기판에 다양한 전처리 방법을 적용하여 SWCNT의 부착력 및 접착력, 투명전극의 면저항, 투과도 및 균일도 향상을 통해 SWCNT 투명전극 특성향상 연구를 진행했다. 접촉각과 표면에너지 제어를 통한 박막특성과의 상관관계 분석, 전처리 방법에 따른 표면에너지 및 제타포텐셜 변화와 박막특성과의 관계를 규명, Roughness 조절을 통한 기판의 면저항과 투과도 향상, 플라즈마 및 polymer 처리를 통해 물리적, 화학적 기판 전처리에 따른 SWCNT 투명전극 특성 향상을 목적으로 실험을 진행했다. 플라즈마 처리 후 polymer 처리된 박막에서는 친,소수 작용기 양의 변화에 따른 상관관계를 보이지 않았지만, 플리즈마 처리 후 친,소수 작용기 양과 Roughness 변화정도에 대해서는 면저항과 투과도의 변화를 보였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.170-170
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• 2017

본 연구의 목표는 극한 지역의 대비 시스템을 구축하기 위하여 인공 신경망(Artificial Neural Networks)을 이용하여 보다 관측하기 쉬운 기상 인자들로부터 적설량을 실시간 측정 가능성을 제시하는 것이다. 본 연구에서 사용한 데이터베이스는 기상청의 기상자료개방포털에서 사람이 직접 측정한 종관기상관측의 자료다. 이 중에서 일최대 기온, 일최저 기온, 일평균 기온, 강수량을 사용하여 오차를 줄여나가는 최적화방법으로 인공 신경망 시스템을 설계하였다. 설계된 시스템으로 500회 시뮬레이션한 연구 결과는 상관계수가 적설량 측정에 대한 인공 신경망의 크기(노드의 개수)와 관계없이 평균적으로 0.8627인 것을 보여준다. 추가적으로 보조 입력 값인 고도를 사용한 결과, 성능은 좋아졌지만 상관계수의 차이는 평균 0.0044로 미세했다. 또한 Cross-Validation을 통해 기존의 보간법인 Kriging기법과 비교하여 미 관측 지역에서 인공 신경망(ANNs) 사용이 Kriging기법 보다 우수하다는 것을 2차원 Regression's map을 통해 나타냈다. 마지막으로 오차가 크게 발생했을 경우 보안할 수 있는 확률적인 방안을 제시하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6958-6965
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• 2014

This study examined the occurring pattern of potential risky species and the related abiotic factors for port-specific environmental management considering the control of ballast water-induced foreign species at Incheon seaport. From a total of 62 species observed during the study, 13 red-tide and 7 toxic phytoplankton, normally occurring species in Korean waters, occurred from the seasonal investigation at the inner and outer sites of the Incheon seaport from 2007 to 2009. The number of potential risky phytoplankton was relatively high at the outer site of the port during summer and winter. Red-tide species, such as Skeletonema spp., Thalassiosira nordenskioldii, and Paralia sulcata, dominated the total standing crops at the inner site (avg. 72.4%) and outer site (avg. 77.6%) in spring and summer, being positively correlated with the concentrations of total suspended solids (TSS) and pH (p<0.05). In summer, the red-tide species (Skeletonema spp.) and toxic species (Alexandrium catenella, A. tamarense, Dinophysis acuminata and Pseudo-nitzschia spp.) co-dominated (avg. 74.2%) at the inner site, while Skeletonema spp. and P. sulcata predominated (avg. 67.2%) at the outer site. During the study periods, the toxic species were significantly and positively correlated with the chemical oxygen demand (COD), dissolved inorganic nitrogen, silicate and phosphate (p < 0.05). The chlorophyll-a (chl-a) concentration of phytoplankton at the outer site ranged from 1.49 to $5.46{\mu}g/L$ on average, which was 3-5 times higher than that at the inner site in spring, summer and autumn, whereas there was no difference in the concentration between inner (avg. $0.94{\mu}g/L$) and outer (avg. $0.95{\mu}g/L$) sites in winter. In summary, diverse red-tide species dominated and a relatively high chl-a concentration existed at the outer site, whereas a relatively high number of toxic species and low chl-a concentration was observed at the inner site in summer. The potential risky species can outbreak in association with the concentration of nutrients, COD and TSS, suggesting that distinctive management of potential risky species is needed considering the environmental characteristics of Incheon seaport.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.3
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• pp.301-309
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• 2012

This study was performed to compare the properties affecting the palatability of 33 commercial brands of rice. Five rice varieties were identified including Chucheongbyeo, Hitomebore, Ilpumbyeo, Nampyeongbyeo, Seachucheongbyeo, were compared in terms of physicochemical characteristics, texture, head riceratio, and palatability through Toyo values. We also analyzed the relationship between grain characteristics and palatability. Amylose content of 5 rice varieties ranged from 17.04-17.98%. Nampyeongbyeo had the lowest and Seachucheongbyeo had the highest content of amylose among rice varieties. The protein content of 5 varieties ranged from 6.72-7.55%. Nampyeongbyeo showed the highest content. The moisture content varied from 13.08-14.83%. Chucheongbyeo has the highest moisture content. The head rice ratio of Ilpumbyeo, Chucheongbyeo, and Seachucheongbyeo were over the 90%, which was lower than that of Japan. Chucheongbyeo had the lowest hardness value and the highest adhesiveness value as measured by texture analyzer. The palatability value was highest in Chucheongbyeo, and the lowest in both Nampyeongbyeo and Ilpumbyeo. The palatability value was negatively correlated with protein content, but positively correlated with texture, moisture content, and head rice ratio. Based on this results, the rice varieties with high palatability had lower contents of amylose and protein, but higher moisture content and head rice ratio. Chucheongbyeo seemed to be the valuable variety with the highest palatability among them.

• Korean Journal of Environment and Ecology
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• v.24 no.6
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• pp.657-679
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• 2010

Mushroom fruiting was investigated in pine and oak dominated forest stands in Songni National Park located in central Korea for six years from 2003 to 2008, in order to understand the relationship between mushroom diversity and the environmental factors, precipitation, temperature, soil moisture and vegetation. The most frequent fruiting families were those of ectomycorrhizal mushrooms, Tricholomataceae, Amanitaceae, Russulaceae, Cortinariaceae, and Boletaceae. The frequency of mushroom fruiting varied from 94 to 167 species per year, with July and August having the highest(13~90 species). Mushroom fruiting was positively correlated to precipitation(r=0.897), using Palmer Drought Severity Index for the long term period and Standard Precipitation Index for short term period. Soil moisture content also affected mushroom fruiting, with Lactarius chrysorrheus and Russula virescens fruiting only at soil moisture content higher than 20%. Positive correlation between mushroom fruiting and temperature was also noted(r=0.77), with optimum rates at $21{\sim}25^{\circ}C$. Tricholoma flayayirens, Amanita gymnopus, Lactarius piperatus, Inocybe asteropora and Xerocomus chrysenteron were able to fruit at temperatures higher than $25^{\circ}C$. However, Laccaria amethystea, Amanita virosa and Russula mariae fruited at relatively wide temperature range. The influence of vegetation on mushroom fruiting was likewise noted, with 38 species, including Suillus bovinus and Boletopsis leucomelas being specific to pine dominated stands, while 42 species, including Polyporus arcularius and Hericium erinaceum were specific to oak dominated stands. On the other hand, around 50 species, including Laccaria laccata and Lycoperdon parlatum, were able to fruit in both types of vegetation. In conclusion, mushroom fruiting greatly varies with changes in precipitation, soil moisture, temperature and vegetation.

• Journal of Life Science
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• v.20 no.11
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• pp.1640-1647
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• 2010

Seaweeds have been recognized as a health food, having anti-obesity, anti-constipation and anticoagulation activities, and the use of seaweeds in the food, medicine, and cosmetic industries have recently significantly increased. In this study, methanol extracts were prepared from 35 different seaweeds (17 phaeophyta, 11 rhodophyta and 7 chlorophyta), and thrombin time (TT), prothrombin time (PT) and activated partial thromboplastin time (aPTT) were determined in order to develop safe and novel anticoagulation agents from natural products. In TT experiments, Ecklonia cava, Ecklonia stolonifera, Eisenia bicyclis (Kjellman) Setchell, Ishige foliacea, I. okamurai, Sargassum confusum and S. yamade showed strong thrombin inhibition activity among the 35 different seaweeds. In PT experiments, the inhibitions of prothrombin were identified in the selected seaweeds from TT experiment, with the exception of S. yamade. In aPTT experiments, the seaweeds with blood coagulation inhibition factors were E. cava, E. stolonifera, E. bicyclis (Kjellman) Setchell, I. foliacea, I. okamurai, S. confusum and Hixikia fusiforme Okamura. Further anticoagulation assay with the selected 8 seaweeds suggested that S. confusum is most effective in antithrombosis, and E. stolonifera, E. bicyclis (Kjellman) Setchell, and I. foliacea have high potential as antithrombosis agents. Based on components-activity correlation analysis, flavonoids are considered as active anticoagulation components of seaweeds These results suggest that edible seaweeds, especially S. confusum, have potential as safe and novel anticoagulants, and S. yamade and H. fusiforme Okamura could be used as a thrombin-specific and coagulation factor-specific inhibitors.

• Korean Journal of Environmental Biology
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• v.42 no.1
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• pp.15-27
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• 2024

The goal of this study was to provide basic data necessary for managing fish in the Seomgang River by confirming diversity of fish species in the Seomgang River and determining the degree of change in fish species through a comparison with earlier related work. Growth rate, obesity level, and temporal and spatial reproductive capacities were analyzed to determine growth characteristics of dominant species. Fish fauna and structure of the fish community were surveyed at three different time points from October of 2020 to August of 2021 at eight sites. In addition, growth characteristics of Zacco platypus from June of 2021 to July of 2022 at four sites were determined. A total of 3,999 individuals, 43 species, and ten families of fish were identified. Among these species, 19 (44.19%) were Korean endemic species and four (9.30%) were endangered species. The dominant species was Z. platypus. Pungtungia herzi was identified as a subdominant species. An analysis of length-weight relationships and condition factor (k) of Z. platypus confirmed a good state of growth. As a result of a frequency analysis of the total length, the life cycle of the Z. platypus population living in the Seomgang River was found to be stable. According to gonadosomatic index (GSI) analysis, the spawning season of Z. platypus was estimated to occur after May, consistent with the literature.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.252-256
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• 2005

Removal of heavy metal ions from aqueous solution by brown sea weeds (Hizikia fusiformis, Laminaria, and Undaria pinnatifida) was 80-96% for lead, cadmium, chromium and copper ions. Fifty percent of the adsorption was completed in 4 min. The uptake of lead and cadmium ions followed Langmuir adsorption. In the adsorption experiments using single and multi metal ions 80-95% of metal ions were removed, and the removal efficiency was the best for lead ion.

• Proceedings of the Korea Concrete Institute Conference
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• 1991.04a
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• pp.1-14
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• 1991

환경문제로 인한 Nox의 규제로 보일러의 연소 온도가 저하되어 미연소탄과 조립분이 증가되었다. 이러한 플라이 애쉬의 미연소탄과 양호하지 못한 입자형상들은 콘크리트용 혼화재로서 플라이 애쉬의 품질을 현저하게 저하시키고 있다. 이 저 품질의 플라이 애쉬를 44$\mu$체를 사용하여 체 분급의 방법을 도입하므로서 어느 정도 양질의 플라이 애쉬로 개선될수 있었다. 분급한 9종의 플라이 애쉬를 시험한 결과 입자형상이 구형으로 개선되었으며, 물리.화학적 특성이 다소 개선되었고 압축강도가 증가되었다. 그리고 분말도와 포졸란 활성지수, 44$\mu$체 잔량과 포졸란 활성지수는 좋은 상관관계를 보여주었다. 또한 분급에 의한 분말도 관리가 포졸란 활성에 영향을 주는 인자임을 알 수 있었다.

• Journal of Korean Medical classics
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• v.18 no.4 s.31
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• pp.134-144
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• 2005

통과대해역병재${\ulcorner}$동의수세보원(東醫壽世保元)${\lrcorner}$중적상관내용여현대의학적비교연구(中的相關內容與現代醫學的比較硏究), 가류추출여하결론(可類推出如下結論): ${\ulcorner}$내경(內經)${\lrcorner}$중출현적해역병, 재척부혹맥적진단법급자침적류오인식상(在尺部或脈的診斷法及刺針的謬誤認識上), 언급도해역병. 저시인위파열(這是因爲把熱), 혈소(血少), 비토허(脾土虛), 상화작위료기근원적연고(相火作爲了其根源的緣故). 해역병적증상시‘한불한(寒不寒), 열불열(熱不熱), 약불약(弱不弱), 장불장(壯不壯)’급(及)‘소삭, 행산, 불능거(不能去)’ 재(在)${\ulcorner}$동의수세보원(東醫壽世保元)${\lrcorner}$중칭위‘기병가유(其病可愈)’, 이종현대의학적각도진행연구결과(而從現代醫學的角度進行硏究結果), 인위유류사여말초신경적병증(認爲有類似與末稍神經的病證). 종현대의학적원인래간(從現代醫學的原因來看), 유어단백질(由於蛋白質)-능량적영양결핍화유생소급미량원소적부족(能量的營養缺乏和維生素及微量原素的不足), 출현말초신경병증(出現末稍神經病證). 재(在)${\ulcorner}$동의수세보원(東醫壽世保元)${\lrcorner}$적약물중(的藥物中), 야유능량화유생소급미량원소등성분(也有能量和維生素及微量原素等成分), 소이인위대태양인적처방(所以認爲對太陽人的處方), 종영양학각도진행분석연구시유가치적(從營養學角度進行分析硏究是有價値的).