• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1400_1401
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• 2009

In this paper describes the comparisons of the surface flashover characteristics according to the change of the insulation media by experimental GIS(Gas Insulated Switchgear) chamber in accordance with change of pressure(P) and electrode distance(d). The using insulation medias are $SF_6$, Dry-Air, I-Air(Imitation Air, $N_2$ : $O_2$ = 79[%] : 21[%]), $N_2:O_2$ mixture gas and pure $N_2$. In this study, in order to compare the properties $SF_6$ and order insulation gas, we investigated the properties of the various insulation media with a knife to knife electrode under ac high voltage application. The gas pressure was changed from 1 to 5[atm]. as a result, it was found that dielectric strength is $SF_6$ > I-Air > Dry-Air and the best environmental preservation gas is Dry-Air.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.5
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• pp.366-374
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• 2010

Introduction: This study evaluated the capability of silk fibroin (SF) and recombinant human bone morphogenetic protein-2 loaded SF (SF-BMP) as a bone defect replacement matrix when grafted in a calvarial bone defect of rats in vivo. Materials and Methods: A total 70 calvarial critical size defects (5.0 mm in diameter) made on 35 adult female Sprague-Dawley rats were used in this study. The defects were transplanted with (1) rhBMP-2 loaded silk fibroin graft (SF-BMP: 0.8+$10\;{\mu}g$), (2) Silk fibroin (SF: $10\;{\mu}g$), and (3) no graft material (Raw). The samples were evaluated with soft x-rays, alkaline phosphatase activity, calcium/phosphate quantification, histological and histomorphometric analysis at postoperative 4 and 8 weeks. Results: The SF-BMP group ($48.86{\pm}14.92%$) had a significantly higher mean percentage bone area than the SF group ($24.96{\pm}11.01%$) at postoperative 4 weeks.(P<0.05) In addition, the SF-BMP group ($40.01{\pm}12.43%$) had a higher % bone area at postoperative 8 weeks than the SF group ($33.26{\pm}5.15%$). The mean ratio of gray scale levels to the host bone showed that the SF-BMP group ($0.67{\pm}0.08$) had a higher mean ratio level than the SF group ($0.61{\pm}0.09$) at postoperative 8 weeks. These differences were not statistically significant.(P=0.168 and P=0.243, respectively) The ratio of the calcium and phosphate contents of the SF-BMP ($0.93{\pm}0.22$) group was lower than that of the SF ($1.90{\pm}1.42$) group at postoperative 4 weeks. However, the SF-BMP group ($0.75{\pm}0.31$) had a higher Ca/$PO_4$ ratio than the SF ($0.68{\pm}0.04$) at postoperative 8 weeks. These differences were not statistically significant.(P=0.126 and P=0.627, respectively) For the bone-specific alkaline phosphatase (ALP) activity, which is recognized as a reliable indicator of the osteoblast function, the SF-BMP ($23.71{\pm}8.60\;U/L$) groups had a significantly higher value than the SF group ($12.65{\pm}6.47\;U/L$) at postoperative 4 weeks.(P<0.05) At postoperative 8 weeks, the SF-BMP ($21.65{\pm}10.02\;U/L$) group had a lower bone-specific ALP activity than the SF group ($16.72{\pm}7.35\;U/L$). This difference was not statistically significant.(P=0.263) For the histological evaluation, the SF-BMP group revealed less inflammation, lower foreign body reactions and higher bone healing than the SF group at postoperative 4 and 8 weeks. The SF group revealed more foreign body reactions at postoperative 4 weeks. However, this immunogenic reaction decreased and the remnant of grafted material was observed at postoperative 8 weeks. For histomorphometric analysis, the SF-BMP group had a significantly longer bone length to total length ratio than those of the SF group at postoperative 4 and 8 weeks.(P<0.05) Conclusion: The rhBMP-2 loaded silk fibroin graft revealed fewer immunoreactions and inflammation as well as more new bone formation than the pure silk fibroin graft. Therefore, silk fibroin may be a candidate scaffold for tissue engineered bone regeneration.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.10
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• pp.1422-1428
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• 2000

This investigation was conducted to evaluate the shrimp flesh (SF) and shrimp by-product (SB) of the most abundant shrimp species (Metapenaeus affinis, Penaeus semisulcatus and Penaeus monodon) caught in Central Vietnam, with the emphasis on yield, gross and amino acid (AA) composition and effect of heat treatment. The results showed that the mean edible SF and SB (head and shells with tail) yields of the three shrimp species averaged 56.7 and 43.3%, respectively, of the total wet body weight, with the M. affinis generating the highest by-product yield (45.7%) and P. semisulcatus (40.6%) the lowest. Significant differences in dry matter (DM), crude protein (CP) and ash content were found between SF and SB. The DM content of SF (21.5%) was lower than of SB (24.9%) and the ash content (on a DM basis) of the SB in all shrimp species was more than three times that of the SF (p<0.05), whereas the CP content was almost twice as high in the SF as compared with the SB (p<0.05). The SB of the three species contained (on a DM basis) between 44.0 and 49.8% CP (p<0.05) and between 13.5 and 18.1% chitin (p<0.05). The Ca content of SB differed also between species (p<0.05). On average, the sum of AA in SB corresponded to 89.3% of the CP and essential AA accounted for about 50% of the total AA. The most abundant AA were arginine, aspartic and glutamic acids, which accounted for 33% of the total AA. Minor, but significant differences in some AA concentrations of SB between species were observed (p<0.05). With the exception of the DM and ether extract content, all other chemical constituents of entire shrimp, SF and SB were not significantly affected by heat treatment (p>0.05).

• The Science & Technology
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• v.35 no.3 s.394
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• pp.86-87
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• 2002

• Journal of the Korean Society of Food Culture
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• v.20 no.4
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• pp.468-475
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• 2005

To determine the effect of different fermentation level on the quality of Nabak Kimchi during storage, this study was carried by analysing the result of physico-chemical properties, microbiological characteristics and sensory evaluation of Nabak Kimchi stored up to 24 days. For the physico-chemical properties, pH, total acidity, reducing sugar, carbon dioxide contents, color values were investigated while for the microbiological characteristics, total microbial counts and lactic acid bacteria were studied. Nabak Kimchi products were fermented at six different level of temperature and time and stored in Kimchi refrigerator at $4^{\circ}C$ for 24 days. As the storage period increased, the pH values of LF15, SF25 and LF25 decreased rapidly after initial fermentation and the pH values of SF4, LF4 and SF15 increased slightly in the beginning and then decreased. total acidity increased as storage period proceeded. the amount of reducing sugar was 4.92mg/ml before fermentation and increased significantly and reached its maximum values then decreased. lightness and redness of Nabak Kimchi decreased as storage period became longer, but yellow of Nabak Kimchi increased during storage. Total microbial counts of SF25 and LF25 reached to the highest at the 6th day and total microbial counts of LF15 reached to the highest at the 12th day and then significantly decreased. However, total microbial counts of SF4, LF4 and SF15 continuously increased up to the 24th day. The number of lactic acid bacteria was similar to the phase of the change of total microbial counts.

• Membrane Journal
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• v.21 no.1
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• pp.22-29
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• 2011

During the maintenance, repair and replacement process of circuit breaker, $SF_6$ reacted with input air in arc discharge, which led to the production of by-product gases (eg, $N_2$, $O_2$, $CF_4$, $SO_2$, $H_2O$, HF, $SOF_2$, $CuF_2$, $WO_3$). Among these various by-product gases, $N_2$, $O_2$, $CF_4$ is major component. Therefore, the effective separation process is necessary to recycle the $SF_6$ gas from the mixture gas containing $N_2$, $O_2$, $CF_4$. In this study, the membrane separation process was applied to recycle the $SF_6$ gas from the mixture gas containing $N_2$, $O_2$, $CF_4$. The concentration of $SF_6$ gas in gas produced from the electric power industry is over than 90 vol%. Therefore, we made the simulated gas containing $N_2$, $O_2$, $CF_4$, $SF_6$ which the concentration of $SF_6$ gas is minimum 90 vol%. From the results of membrane separation process of $SF_6$ gas from $N_2$, $O_2$, $CF_4$ $SF_6$ mixture gases, PSF membrane shown the highest recovery efficiency 92.7%, in $25^{\circ}C$ and 150 cc/min of retentate flow rate. On the other hand, PC membrane shown the highest recovery efficiency 74.8%, in $45^{\circ}C$ and 150 cc/min of retentate flow rate. Also, the highest rejection rate of $N_2$, $O_2$, $CF_4$ is 80, 74 and 58.9% seperately in the same operation condition of highest recovery efficiency. From the results, we supposed the membrane separation process as the effective $SF_6$ separation and recycle process from the mixture gas containing $N_2$, $O_2$, $CF_4$, $SF_6$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1502-1507
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• 2012

The purpose of this study was to evaluate the antioxidant contents and activities of solvent fractions from methanolic extracts of cockscome flowers. The yield of methanolic extracts from cockscome flowers was 23.33%, whereas those of its solvent fractions (hexane, chloroform, ethyl acetate, butanol, and water) were 10.27, 20.00, 13.63, 17.55, and 38.54%, respectively. Total polyphenolic, flavonoid, tannin, and proanthocyanidin contents of methanolic extracts (ME) were 6.80 mg gallic acid equivalent (GAE)/g ME, 2.34 mg catechin equivalent (CE)/g ME, 6.23 mg tannic acid equivalent (TAE)/g ME, and $44.72{\mu}g$ CE/g ME, respectively. The highest total polyphenolic, flavonoid, and tannin contents of solvent fractions were 14.92 mg GAE/g solvent fraction (SF), 5.44 mg CE/g SF, and 13.38 mg TAE/g SF in the butanol fraction, respectively. The total proanthocyanidin contents were 42.47, 44.43, 50.03, 49.12, and $41.80{\mu}g$ CE/g SF, respectively. The DPPH and ABTS radical scavenging activities from cockscome flowers were 5.24 and 10.70 mg Trolox equivalent (TE)/g ME, respectively. The highest DPPH and ABTS radical scavenging activities of the solvent fractions were 12.53 and 21.09 mg TE/g SF in the butanol fraction, respectively. SOD-like activities of methanolic extracts from cockscome flowers were 7.96 units/mL, whereas those of its solvent fractions were 4.56, 6.15, 8.07, 12.36, and 5.21 units/mL, respectively. The results of this study show that notable antioxidant activities in cockscome flowers have significant health benefits.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.4
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• pp.305-310
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• 2008

Deep trench etching of silicon was investigated as a function of RF source power, DC bias voltage, $C_4F_8$ gas flow rate, and $O_2$ gas addition. On increasing the RF source power from 300 W to 700 W, the etch rate was increased from $3.52{\mu}m/min$ to $7.07{\mu}m/min$. The addition of $O_2$ gas improved the etch rate and the selectivity. The highest etch rate is achieved at the $O_2$ gas addition of 12 %, The selectivity to PR was 65.75 with $O_2$ gas addition of 24 %. At DC bias voltage of -40 V and $C_4F_8$ gas flow rate of 30 seem, We were able to achieve etch rate as high as $5.25{\mu}m/min$ with good etch profile.

• The Journal of the Korea Contents Association
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• v.14 no.6
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• pp.288-297
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• 2014

The purpose of this study was to investigate the quality of life related to swallowing through Swallowing-Quality Of Life(SWAL-QOL) and examine the impact of SWAL-QOL on overall quality of life measured by Short-Form Health Survey(SF-36) and Geriatric Quality of Life(GQOL). For this purpose, the SWAL-QOL, SF-36 and GQOL have been conducted on 140 old people who were all over 60 years of age and physically and mentally normal. The collected data have been analyzed using a Windows SPSS 21.0 program. The results show that the SWAL-QOL are significant differences according to age(F=7.76, p<.01) and aspiration(t=-4.44, p<.01) and aspiration is ouly factor affecting the SW AL-QOL in elderly people. There are significant correlations between SF-36, GQOL and SW AL-QOL and the pearson product moment correlation coefficient is .39(p<.01) and .33(p<.01) respectively. The SWAL-QOL can predict approximately 36% and 25% of quality of life measured by SF-36 and GQOL. Therefore, this result will be able to utilize as basic data to improvement of quality of life related swallowing and overall quality of life related to health in normal elderly people.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.166-173
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• 2020

The purpose of the present study was to validate the Need for Closure Scale-Short Form (NFCS-SF), which measures the need for cognitive closure. Participants completed questionnaires regarding need for cognitive closure, intolerance of uncertainty, depression, and anxiety. Of the 536 data collected between May and July 2017, data from a total of 495 participants were analyzed using SPSS 20.0 and M-Plus. The results of the study are as follows. First, a 15-item selection comprised three items from each facet scale via exploratory factor analysis. Second, the NFCS-SF demonstrated good internal consistency (Study 1, Cronbach's α=.85; Study 2, Cronbach's α=.84). Third, the results of the confirmatory factor analyses supported a 5-factor model (χ2(80)=178.34, p<.001; CFI=.87, TLI=.83, RMSEA=.07, SRMR=.08). Fourth, the NFCS-SF showed significant correlation with the measures of intolerance of uncertainty (r=.58, p<.01), depression (r=.16, p<.05), and anxiety (state anxiety, r=.31, p<.01; trait anxiety, r=.29, as well as the NFCS (r=.86, p<.01). Based on these findings, significance and limitations of the results as well as suggestions for further study are discussed.