• 한국광학회:학술대회논문집
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• 한국광학회 2003년도 제14회 정기총회 및 03년 동계학술발표회
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• pp.224-225
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• 2003

Since group velocity (GV) mismatch significantly limits the efficiency of nonlinear interactions such as second harmonic generation (SHG), several techniques have been developed to compensate GV mismatch. The simplest way to avoid the GV mismatch problem is to reduce the device length. However, it results in a poor trade-off between the SHG spectral bandwidth and the conversion efficiency. (omitted)

• 한국식품영양과학회지
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• 제27권1호
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• pp.157-162
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• 1998

The antimutagenic activity of three kinds of extract such as fresh juice, ethanol extract and water extract of Artemisia iwayomogi against 3 - amino - 1, 4 - dimethyl - 5H - pyrido [4,3-b] indol (Trp-P-1) and N - methyl - N' - nitro - N -nitrosoguanidine(MNNG) was demonstrated with the Salmonella typhimurium assay. The number of revertants per plate decreased significantly when these extracts(0.5ug/plate) added to the assay system system using S. typhimurium TA 100. These extracts also showed prominant cytotoxic activity against four different kinds of human cancer cell as human lung cancer cell (A549), breast cancer cell(MCF7), fibrosacoma cell(HT1080) and gastric cancer cell(KATOIII), respectively.

• 전기화학회지
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• 제5권4호
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• pp.212-215
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• 2002

A superoxide dismutase (SOD)-based superoxide ion $(O_2^-)$ sensor was fabricated by immobilizing SOD on a self-assembled monolayer (SAM) of 3-mercaptopropionic acid (MPA) which was prepared on a gold electrode. The SAM of MPA was found to function as an effective promoter for the electrode reaction of SOD. The amperometric response to $(O_2^-)$ was monitored at 300mV and -100mV vs. Ag/ Agel in 5mM phosphate buffer solution containing $KO_2$. The sensor was proved to have a high sensitivity, selectivity and short response time (<5 s) and negligible interference.

• Progress in Superconductivity
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• 제14권2호
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• pp.82-86
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• 2012

A sensitive eight-channel high-Tc Superconducting Interference Device (SQUID) detection system for magnetic contaminant in a lithium ion battery anode was developed. Finding ultra-small metallic foreign matter is an important issue for a manufacturer because metallic contaminants carry the risk of an internal short. When contamination occurs, the manufacturer of the product suffers a great loss from recalling the tainted product. Metallic particles with outer dimensions smaller than 100 microns cannot be detected using a conventional X-ray imaging system. Therefore, a highly sensitive detection system for small foreign matter is required. We have already developed a detection system based on a single-channel SQUID gradiometer and horizontal magnetization. For practical use, the detection width of the system should be increased to at least 65 mm by employing multiple sensors. In this paper, we present an 8-ch high-Tc SQUID roll-to-roll system for inspecting a lithium-ion battery anode with a width of 65 mm. A special microscopic type of a cryostat was developed upon which eight SQUID gradiometers were mounted. As a result, small iron particles of 35 microns on a real lithium-ion battery anode with a width of 70 mm were successfully detected. This system is practical for the detection of contaminants in a lithium ion battery anode sheet.

• Fisheries and Aquatic Sciences
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• 제13권2호
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• pp.190-194
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• 2010

In recent years, several southern coastal fish farms in Korea have experienced 2-30% mortality in striped beakperch suffering from bacterial infections during the spring. In this study, we identified a bacterium isolated from diseased striped beakperch as Pseudomonas anguilliseptica via a biochemical test and 16S rDNA sequence analysis. To evaluate the susceptibility of striped beakperch to P. anguilliseptica, $4.39\times10^7$ or $4.39\times10^5$ CFU/fish of bacteria were injected intraperitoneally at $18\pm1^{\circ}C$ into fish weighing 5.5 g. Cumulative mortalities reached 100% and 45% in the $4.39\times10^7$ and $4.39\times10^5$ CFU/fish infected groups, respectively. Experimentally infected fish showed cell-associated inflammation as well as bacteria in the kidneys and spleen. This study is the first report of striped beakperch mortality caused by P. anguilliseptica, which has pathogenicity in striped beakperch.

• 생명과학회지
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• 제30권1호
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• pp.40-44
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• 2020

한인진의 용매별 분획물에 관한 항염증, 항균효과를 조사하기 위하여 용매별로 추출하여 그 수율을 조사하여 본 결과, H₂O 층에서는 64.20%로 가장 높은 수율을 나타내었으며, Hexane층(16.05%), Chloroform, Ethyl acetate 층(각각 11.11%)의 순으로 조사되었다. 항산화 활성을 알아보기 위한 DPPH와 ABTs 소거활성을 분석한 결과 Ethyl acetate층에서 각각 12.32 ppm, 7.058 ppm로 가장 높은 소거능을 나타내었고 페놀화합물 및 플라보노이드 함량 분석결과 역시 Ethyl acetate 674.13 mg GA/g, Ethyl acetate 232.5 mg GA/g으로 가장 높게 나타났다. 항균 테스트 결과 황색포도상구균인 Staphylococcus aureus 에서 한인진의 Hexane 층은 모든 농도에서 13-18 mm의 Inhibition zone을 보이며 메탄올 추출물에서 16-10 mm 나타냈고, Chloroform층에서도 1,000 ppm에서 15 mm로 나타났다. 염증세포인 RAW 264.7 세포에서 염증억제효과 및 독성을 확인 한 결과 물층을 제외하고 나머지 분획층에서는 염증유발 물질인 LPS를 처리한 군보다 2-9배 이상 효과를 보이는 것으로 확인되었다. 특히 Ethyl acetate층에서 대조군 보다 9배 이상의 높은 항염증효과를 보였으나 세포독성은 나타나지 않는 것으로 확인되었다.

• 생명과학회지
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• 제16권5호
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• pp.746-749
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• 2006

구절초 전초의 chloroform 분획물로부터 2종의 flavonoid화합물을 분리하여 NMR을 통해서 구조를 확인한 결과, luteolin (1)과 acacetin (2)으로 구조 동정되었다. 이들의 화합물 중에서 luteolin (1)은 구절초에서 처음으로 분리하였다. 분리된 화합물은 sulforhodamine B (SRB) assay법에 따라 인체암세포주인, HCT116 (결장암) , UO-31 (신장암), PC-3 (전립선암) 와 A549 (폐암)등에 대한 in vitro에서의 세포독성을 실험하였다. 그 결과, acacetin (2)이 HCT116 $(IC_{50}\;2.44\;{\mu}g/ml)$과 UO-31 $(IC_{50}\;2.89\;{\mu}g/ml)$에서 유의할만한 세포독성을 나타내었다.

• Journal of Ecology and Environment
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• 제33권2호
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• pp.141-147
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• 2010

This study compared the antimicrobial activity and chemical composition of two plants used as "Injin" (Korean herbal medicine), namely, Injinho (Artemisia capillaris Thunberg) and Haninjin (Artemisia iwayomogi Kitamura). The ethyl acetate and ether fractions of crude methanol extracts from A. capillaris and A. iwayomogi were tested against three grampositive bacteria (Bacillus cereus, Bacillus subtilis, Staphylococcus aureus), two gram-negative bacteria (Escherichia coli, Pseudomonas fluorescens), and a yeast (Saccharomyceus cerevisiae). The antimicrobial activity of the ethyl acetate and ether fraction of both plants was strong, but that of A. iwayomogi extracts was higher than that of A. capillaris extract for the microbes tested. The minimum inhibitory concentration of the ether and ethyl acetate fraction of A. iwayomogi was highest for P. fluorescens and lowest for S. aureus and E. coli. We analyzed the chemical composition of the ethyl acetate fraction of A. capillaris and A. iwayomogi using gas chromatography-mass spectrometry. The main components of A. capillaris and A. iwayomogi were escoparone (86.82%) and scopoletin (20.47%), respectively.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권1호
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• pp.44-51
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• 2019

Designing sophisticate ship structures that satisfy several design criteria simultaneously with minimum weight and cost is an important engineering issue. For a ship structure composed of a shell and stiffeners, this issue is more serious because their mutual effect has to be addressed. In this study, a two-stage optimization method is proposed for the conceptual design of stiffeners in a ship's prow. In the first stage, a topology optimization method is used to determine a potential stiffener distribution based on the optimal results, whereupon stiffeners are constructed according to stiffener generative theory and the material distribution. In the second stage, size optimization is conducted to optimize the plate and stiffener sections simultaneously based on a parametric model. A final analysis model of the ship-prow structure is presented to assess the validity of this method. The analysis results show that the two-stage optimization method is effective for stiffener conceptual design, which provides a reference for designing actual stiffeners for ship hulls.

• 원예과학기술지
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• 제16권2호
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• pp.247-250
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• 1998

국화의 생육단계별 적정 양액농도를 구명하기 위해 국화의 생육단계를 영양생장기 2단계와 생식생장기 1단계, 즉 3단계로 나누어 양액농도를 처리한 결과, 영양 생장기에서는 1배액에서 초장이 가장 길었고, 광합성과 증산량도 가장 높았다. 그러나 엽내 엽록소 농도는 양액의 농도가 높을수록 컸다. 화아형성이후, 생육 (초장, 엽면적, 경경)과 각 기관별 생체중, 건물중에서도 1배액처리구가 좋았으며, 특히 화아형성이후 수돗물 관수에 의해서도 1배액과 비슷하거나 오히려 더 좋게 나타났다. 그리고 수돗물 관주처리에서 개화소요일수가 짧았다. 이와 같은 결과는 양액의 관주 농도가 높을수록 배지내 염류집적으로 식물체가 스트레스를 받은 것으로 사료된다. 국화의 생육단계별로, 초기 활착기까지는 1/2배액으로 한 후 생육이 왕성한 영양생장기에는 1배액으로, 화아형성 이후에는 양액의 농도를 줄이는 것이 국화 양액재배시 비료염의 절약, 개화소요일수 단축, 배지내 비료염 축적의 감소, 지하수 오염의 감소 등 경제적이고 환경친화적인 방법이라고 사료된다.