• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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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)

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.1
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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.

• Journal of the Korean Electrochemical Society
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• v.5 no.4
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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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• v.14 no.2
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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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• v.13 no.2
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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.

• Journal of Life Science
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• v.30 no.1
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• pp.40-44
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• 2020

This study investigated the anti-bacterial and anti-inflammatory activities of Artemisia iwayomogi Kitamura for medical and food additive applications. A 70% methanol extract of A. iwayomogi Kitam. was fractionated with a series of solvents in order of increasing polarity; these fractionated extracts showed high 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) scavenging activity in the ethyl acetate fractions and high 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity in both the ethyl acetate and chloroform fractions. Levels of total phenolics and flavonoids were highest in the ethyl acetate fraction extracts. Eight bacteria were then treated with the A. iwayomogi Kitam. extract fractions and most showed similar or lower levels of anti-bacterial activity when compared to the control group, except for Staphylococcus aureus. In addition, the anti-oxidant activities of the ethyl acetate fractions of the A. iwayomogi Kitam. extract were higher than those of the other fractions. To confirm the anti-inflammatory activity of the extract fractions, we applied them to RAW 264.7 cells using LPS, and the results indicate that an ethyl acetate fraction at 250 ㎍/ml concentration inhibits nitric oxide production. This study demonstrates that an ethyl acetate fraction of A. iwayomogi Kitam. extract inhibits bacterial and inflammatory activities and could be useful as a potential source of bioactive compounds.

• Journal of Life Science
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• v.16 no.5
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• pp.746-749
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• 2006

Two known flavonoids, luteolin (1) and acacetin (2) were isolated from a $CHCI_3$ soluble fraction of the whole plants of Chrysanthemum zawadskii Herbich var. latilobum Kitamura, and their structures were determined by NMR analysis. The luteolin (1) was isolated from this plant for the first time. These compounds were examined for their in vitro cytotoxic activities against four human cancer cell lines including HCT116 (colon), UO-31 (renal), PC-3 (prostate) and A549 (lung) by sulforhodamine B(SRB) assay. Acacetin (2) showed significant cytotoxic activity against HCT116 and UO-31 cells with an $IC_{50}$ of 2.44 and $2.89\;{\mu}g/ml$, respectively.

• Journal of Ecology and Environment
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• v.33 no.2
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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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• v.11 no.1
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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.

• Horticultural Science & Technology
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• v.16 no.2
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• pp.247-250
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• 1998

This study was carried out to investigate the effects of changes of ionic strength according to growth stage on growth and flowering of Dendranthema grandiflorum (Ramat.) Kitamura 'Seiun' grown hydroponically in perlite. The stage I, II, and III covered early vegetative growth (27-40 days after planting), latter vegetative growth (41-54 days), and reproductive growth (55-80 days), respectively. The 2 strength (1S and 2S) of nutrient solution were treated in stage I, whereas 3 strengths (1S, 1-2S, and 2S) were treated in stage II. Then, total 9 treatments in stage III were designated by 3 treatments (tap water, 1S, and 2S) for each 3 strengths in stage II. Each nutrient solution was applied 8 times per day. At vegetative growth stage (54 days after planting), stem length was highest when irrigated 8 times a day with 1S nutrient solution. Both photosynthesis and transpiration rate were higher in 1S than those in other treatments (1-2S, 2S), whereas leaf chlorophyll content was highest in 2S treatment. Ion content of plant treated with 2S was higher than other treatments. Growth (plant height, leaf area, stem length), fresh weight, and dry weight of each plant organ after flower bud formation were better in tap water treatment (1-1-0) than other 1S treatments (1-1-1, 1-1-2). Regarding the number of days to flowering, tap water treatment was the most effective. Thus, after flower bud formation supplying tap water or lower concentration of nutrient solution than those used during the vegetative growth stage was economical in saving chemical fertilizers, shortening the number of days to flowering, reducing salt accumulation in media, saving efforts of leaching, and reducing ground water contamination.