• Proceedings of the PSK Conference
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• 2003.10b
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• pp.192.2-192.2
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• 2003

Apigenin-7-O-${\beta}$-D-glucoside, chrysoeriol, and luteolin were isolated from the aqueous ethanolic extract of Zostera marina L. leaves as the scavengers of reactive oxygen species (ROS) with the SC$\_$50/ values of 0.18 mM, 0.68 mM, and 0.18 mM against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 0.04 mM, 0.03 mM, and 0.01 mM against superoxide radicals in the xanthine/xanthine oxidase system, respectively. The luteolin suppressed the expression of matrix metalloproteinase-1 (MMP-1) up to 44% at 4.0 ${\mu}$M. (omitted)

• The Korean Journal of Malacology
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• v.22 no.2
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• pp.97-108
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• 2006

Genomic DNA samples isolated from geographical purple Washington clam (Saxidomus purpuratus) were obtained from two different regions in Korean Peninsula: Gunsan (Gunsan population; GSP), and Haeju (Haeju population; HJP), a collection area in the vicinity of the West Sea. The seven arbitrarily primers, OPA-07, OPA-09, OPA-18, OPA-20, OPC-03, OPC-06 and OPC-09 were shown to generate the total loci, loci observed per primer, shared loci by each population, specific, and polymorphic loci which could be clearly scored. We also generated the unique shared loci to each population and shared loci by the two populations in purple Washington clam. The size of the DNA fragments also varied wildly, from 50 to 2,400 bp. Here, 304 total loci were identified in the GSP purple Washington clam population, and 282 in the HJP: 91 polymorphic loci (29.9%) in the GSP and 47 (16.7) in the HJP. 198 shared loci, with an average of 28.3 per primer, were observed in the GSP population. The decamer primer OPA-07 generated the shared loci by the two populations, approximately 1,000 bp, between the two Saxidomus populations. The oligonucleotide primer OPC-03 also generated the shared loci by the two populations, approximately 500 bp and 1,000 bp, in GSP population from Gunsan and HJP population from Haeju. The other primer, OPC-06 generated the shared loci by two Gomphina populations (approximately 400 bp). The dendrogram, generated by seven reliable primers, indicates three genetic clusters. The dendrogram obtained by the seven primers indicates three genetic clusters: cluster 1 (GUNSAN 01-GUNSAN 02), cluster 2 (GUNSAN 03-GUNSAN 11), and cluster 3 (HAEJU 12-HAEJU 22). The genetic distance between the two geographical populations ranged from 0.043 to 0.506. Especially, the longest genetic distance displaying significant molecular differences, 0.506, was found to exist between individuals GUNSAN no. 11 of Gunsan and HAEJU no. 17 of Haeju.

• Journal of the Mineralogical Society of Korea
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• v.24 no.4
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• pp.313-320
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• 2011

Mica-type phyllosilicate particles in the shales of the Manhang formation at the Taeback area in the Kangwon Province were studied using electron probe microanalysis (EPMA) and transmission electron microscopy (TEM). The average chemical formula of the mica-type phyllosilicate mineral analysed by EPMA is $K_{1.35}(Fe_{0.18}Mg_{0.03}Al_{3.86})(Si_{6.55}Al_{1.45})O_{20}(OH)_4$. Low K contents compared to the ideal chemistry of muscovite indicate the presence of illite in the mica-type phyllosilicate particle. X-ray diffraction study showed that pyrophyllite commonly coexists with muscovite in the shales from the Manhang Formation. TEM observations showed both the interlayer and intralayer mixing of $9.3-{\AA}$ pyrophyllite and $10-{\AA}$ muscovite layers. The low K content of the mica-type phyllosilicates apparently come from the close mixing of pyrophyllite and muscovite.

• Journal of the Ergonomics Society of Korea
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• v.18 no.2
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• pp.25-34
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• 1999

The objective of this study is to evaluate the emotional change of a driver according to the change of temperature, humidity, $CO_2$ gas concentration and $C_4H_{10}$ gas concentration in the automobile by electroencephalogram(EEG) spectrum analysis. The experiment was performed in an automobile simulated shielding room with healthy volunteers(age : 18-31, male : 14, female : 7). The subject's emotion at every different condition was indexed 11-point scale(+5 : most pleasant, -5 : least pleasant). The emotion index at each condition resulted in as follows; in temperature $1.00(23.5^{\circ}C)$, $-2.33(30.5^{\circ}C)$, in humidity 1.50(45%), -1.50(65%), in $CO_2$ gas concentration 0.67(500ppm), -0.57(6,000ppm), in $C_4H_{10}$ gas concentration -0.25(0ppm), -2.75(1,200ppm). From EEG spectrum analysis, the average mean power frequency(MPF) value at each different condition was shown as follows; in temperature $5.48(23.5^{\circ}C)$, $4.06(30.5^{\circ}C)$, in humidity 11.03(45%), 3.03(65%), in $CO_2$ gas concentration 7.16(500ppm), 6.38(6,000ppm), in $C_4H_{10}$ gas concentration 10.21(0ppm), 2.87(1,200ppm). When the environment became unpleasant to the subject, all of the obtained MPF values were decreased. It was found that there is close agreement between subjective evaluation by subject's scaling and objective evaluation by EEG spectrum analysis at different environment. These results indicated that the EEG spectrum analysis is a proper method to assess emotional response of a driver in the changing automobile environment.

• Korean Journal of Food Science and Technology
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• v.48 no.2
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• pp.128-132
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• 2016

In this study, polyethylene glycol (PEG) was used to improve DNA amplification efficiency during whole genome amplification (WGA). Amplification efficiency was determined by adding PEG with different molecular weights to the WGA reaction. The greatest increase in amplification efficiency was obtained with PEG 4,000 used at 1.5% concentration. Foodborne pathogenic DNA was amplified by WGA and quantitatively analyzed by real-time polymerase chain reaction. DNA of Salmonella serotype Typhimurium, Listeria monocytogenes, and Vibrio parahaemolyticus was amplified 7,777.01, 9,981.22, and 1,239.03 fold, respectively, by WGA. On adding PEG in the WGA reaction (i.e., enhanced WGA [eWGA]), 18-40-fold more DNA amplification was achieved. Thus, these analyses showed that foodborne pathogens, which are usually present at very low concentration in foods, can be detected by real-time PCR and WGA.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3614-3621
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• 2009

In this paper, A CMOS low-voltage current mode integrator is designed. The designed current-mode integrator is based on linear cascode circuit that is newly proposed in this paper. When it is compared with gain(43.7dB) and unity gain frequency(15.2MHz) of the typical current-mirror type current-mode integrator, the proposed linear cascode current-mode integrator achieves high current gain(47.8dB) and unity gain frequency(27.8MHz). And a 5th Chebyshev current-mode filter with 7.03MHz cutoff frequency is designed. The designed all circuits are simulated by HSPICE using 1.8V-$0.18{\mu}m$ CMOS technology.

• Korean Journal of Organic Agriculture
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• v.26 no.3
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• pp.477-488
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• 2018

This study examined the total phenolic and flavonoid compounds, and the antioxi dant activity of major cultivars of Prunus mume in Korea. The total phenolic content ranged from 64.13 to $93.43mg{\cdot}100g^{-1}$, with the content in 'Osuku' being higher than that in the other cultivars; a difference in the content among cultivars was observed. The total flavonoid content was $6.16{\sim}18.57mg{\cdot}100g^{-1}$, showing a significant difference, with the highest content being noted in 'Gojirou'. The DPPH radical scavenging activity was measured and was relatively high for Nanko, Kamakami, Natsuka, Dana, and Osuku cultivars. When ABTS radical scavenging activity was measured, all the cultivars showed a scavenging activity over 80%, with the scavenging activity of 'Osuku' being the highest. With respect to nitrite scavenging ability, all cultivars exhibited a high scavenging activity of over 50%, with the highest activity observed for 'Nanko' (76.03%), 'Gojirou' (70.56%), and 'Yourou' (70.32%). Based on the study results, it is considered that Prunus mume can be a useful resource because of various substances with functional physiological activities.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.11
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• pp.1299-1308
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• 2007

In this paper, we propose the calibration method of monopulse slope to minimize the variation of angle estimate in frequency agile noncoherent monopulse system. We analyze the monopulse slope characteristics of antenna and RF receiver including the phase and gain imbalances of each receiving channel and present the calibration method to minimize the phase and gain imbalances of RF receiver channels including antenna. In addition, we present the calibration method using channel switching to minimize the gain imbalance of IF receiver channels. The measured average monopulse slope within the frequency bandwidth is -0.96, the maximum variation of angle estimate is similar to theoretical value, $0.15^{\circ}$ at ${\pm}2^{\circ}$ azimuth and $0.03^{\circ}$ at $0^{\circ}$ azimuth.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1105-1110
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• 2011

After pure titanium Ingot(G2) with 400mm in diameter was manufactured, the analysis of its ingredients showed that the oxygen content was 0.073wt% and the iron content was 0.03wt%, which made ASTM Gr.2 standardization satisfactory. The processed titanium ingot produced 42mm wire rod, and hot rolling of 18th phase produced 9mm wire rod. The hardness analysis of 15.8mm wire rod, which was processed in hot rolling of 10th phase from the surface to the center, resulted in almost constant value with Hv150~200. The last 9mm wire rod had a different yield strength and elongation percentage depending on the temperature as it was led in to a hot roller. However, tensile strength revealed an approximate value and made ASTM B863 standardization satisfactory.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.5
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• pp.679-683
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• 2003

Strawberries were fermented for their effective value added product. In alcohol fermentation of strawberries, alcohol content was maximum value (9.22% ) under the condition of 16.32$^{\circ}$Brix of initial sugar concentration, 53.03 hr of fermentation time and 28.8$^{\circ}C$ of fermentation temperature. Acetic acid content revealed minimum value (0.49%) under the condition of 13.18$^{\circ}$Brix of initial sugar concentration, 50.99 hr of fermentation time and 24.96$^{\circ}C$ of fermentation temperature. Residual sugar content revealed minimum value (3.97$^{\circ}$Brix) under the condition of 15.00$^{\circ}$Brix, 52.00 hr and 26.0$0^{\circ}C$. The optimum conditions for each alcohol fermentation were 14$^{\circ}$Brix, 50 hr and 28$^{\circ}C$.