• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.343-349
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• 2019

Gul jeotgals (GJs) were prepared using solar salt aged for 3 years. One sample was fermented using starters, such as Bacillus subtilis JS2 and Tetragenococcus halophilus BS2-36 (each $10^6CFU/g$), and another sample was fermented without starters for 49 days at $10^{\circ}C$. Initial counts of bacilli and lactic acid bacteria (LAB) in non-starter GJ were found to be $3.20{\times}10^2$ and $7.67{\times}10^1CFU/g$ on day 0, and increased to $1.37{\times}10^3$ and $1.64{\times}10^6CFU/g$ on day 49. Those of starter GJ were found to be $2.10{\times}10^5$ and $3.30{\times}10^7CFU/g$ on day 49, indicating the growth of starters. The pH values of GJ were $5.93{\pm}0.01$ (non-starter) and $5.92{\pm}0.01$ (starter) on day 0 and decreased to $5.78{\pm}0.01$ (non-starter) and $5.75{\pm}0.01$ (starter) on day 49. Amino-type nitrogen (ANN) production increased continuously during fermentation, and $407.19{\pm}15.85$ (non-starter) and $398.04{\pm}13.73$ (starter) mg% on day 49. Clone libraries of 16S rRNA genes were constructed from total DNA extracted from non-starter GJ on days 7, 21, and 42. Nucleotide sequences of Escherichia coli transformants harboring recombinant pGEM-T easy plasmid containing 16S rRNA gene inserts from different bacterial species were analyzed using BLAST. Uncultured bacterium was the most dominant group and Gram - bacteria such as Acidovorax sp., Afipia sp., and Variovorax sp. were the second dominant group. Bacillus amyloliquefaciens (day 7), Bacillus velezensis (day 21 and 42), and Bacillus subtilis (day 42) were observed, but no lactic acid bacteria were detected. Acidovorax and Variovorax species might play some role in GJ fermentation. Further studies on these bacteria are necessary.

• Korean Educational Research Journal
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• v.43 no.1
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• pp.1-27
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• 2022

As the COVID-19 virus became prevalent worldwide, non-face-to-face contact was implemented in various ways, and the education system also began to draw much attention due to rapid non-face-to-face contact. The purpose of this study is to analyze the direction of non-face-to-face education in line with the continuously changing educational environment to date. In this study, data were visualized using Textom and Ucinet6 analysis tool programs to collect social network big data with various opinions. As a result of the study, keywords related to "COVID-19" were dominant, and keywords with high frequency such as "article" and "news" existed. As a result of the analysis, various issues related to non-face-to-face education, such as network failures and security issues, were identified. After the analysis, the direction of the non-face-to-face education system was studied according to the growth of the education market and changes in the educational environment. In addition, there is a need to strengthen security and feedback on teaching methods in non-face-to-face education analyzed using big data.

• Structural Engineering and Mechanics
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• v.67 no.5
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• pp.545-553
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• 2018

Mode II delamination propagation is an important damage mode in laminated composites and this paper aims to investigate the behavior of this damage in laminated composite materials using acoustic emission (AE) technique. Three different lay-ups of glass/epoxy composites were subjected to mode II delamination propagation and generated AE signals were recorded. In order to investigate the propagation of delamination behavior of these specimens, AE signals were analyzed using Wavelet Packet Transforms (WPT) and Fast Fourier Transform (FFT). In addition, conventional AE analyses were used to enhance understanding of the propagation of delamination damage. The results indicate that different fracture mechanisms were the main cause of the AE signals. The dominant mechanisms in all the specimens were matrix cracking, fiber/matrix debonding and fiber breakage, with varying percentage of the damage mechanisms for each lay-up. Scanning Electron Microscopy (SEM) observations were in accordance to the AE results.

• Transactions of Materials Processing
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• v.21 no.6
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• pp.372-377
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• 2012

In this study, the plastic flow behaviors of extra deep drawing quality (EDDQ) steel subjected to non-proportional strain paths were investigated. Two-step uniaxial tension tests, in which the first step was performed in the rolling direction (RD) and the subsequent test in different directions in $15^{\circ}$ increments from the RD, were conducted. The experiments clearly showed that stress overshooting and strain hardening stagnation were the dominant features, which were captured reasonably well using a recently proposed distortional hardening model.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.50
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• pp.91-103
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• 1999

This paper deals with effectiveness of Object-Oriented Modeling and Design(OOMD) through GroupSystems V which is a typical groupware or group decision support system(GDSS) to aid group work. Objective and subjective evaluations between traditional non-GDSS face-to-face group and GDSS-supported group have been performed in terms of modeling accuracy and subjective ratings, respectively. Experimental results indicate that the GDSS group shows much better performance than the traditional group in the realm of OOMD. In particular, when a modeling task is not simple or not structured, the former outperforms the latter. Based on the questionaire, the GDSS group feel more equal status and have less dominant voices than do the non-GDSS group. These facts show that GDSS can be used effectively for OOMD under Korean cultures.

• Journal of Integrative Natural Science
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• v.1 no.2
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• pp.115-121
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• 2008

This study was performed to examine the effect of ${\gamma}$-irradiation on the volatile organic compounds of Cuscutae Semen (Cuscuta chinensis L.). The volatile organic compounds of non-irradiated and 10 kGy ${\gamma}$-irradiated Cuscutae Semen were isolated using SDE apparatus and analyzed by GC/MS. Limonene, ethanol, (E)-2-decenal, hexadecanol, nonanoic acid and nonanal were detected as dominant compounds. Before irradiation, the total concentration of volatile organic compounds of Cuscutae Semen was approximately 189.90 mg/kg. After irradiation at 10 kGy, total concentrations increased to 299.46 mg/kg, but, the profile of volatile compounds including the essential oils of Cuscutae Semen was not differ from non- and irradiated sample. Therefore it was improved the extraction yield of useful compounds such as limonene, menthol, piperitone and isomenthone by irradiation.

• Geomechanics and Engineering
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• v.9 no.1
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• pp.83-100
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• 2015

Water and energy supplies are the key factors affecting the economic development and environmental improvement of Turkey. Given their important role and the fact that a large part of Turkey is in seismically active zones dams should be accurately analyzed since failure could have a serious impact on the local population environment and on a wider level could affect the economy. In this paper, a procedure is proposed for the static, slope stability, seepage and dynamic analysis of an earth dam and the Pamukcay embankment dam. The acceleration time history and maximum horizontal peak ground accelerations of the $Bing\ddot{o}l$ (2003) earthquake data was used based on Maximum Design Earthquake (MDE) data. Numerical analysis showed that, the Pamukcay dam is likely to experience moderate deformations during the design earthquake but will remain stable after the earthquake is applied. The result also indicated that, non-linear analysis capable of capturing dominant non-linear mechanism can be used to assess the stability of embankment dams.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.316-321
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• 2000

This study carried out to eluciate the cancer chemoprevention of Korean native fermented food, baechu kimchi using Comet assay (in other words, single cell microgel electrophoresis). For this purpose, baechu kimchi was fractionated by water, n-hexane, chloroform and ethyl acetate. 5 strains of dominant fermented bacteria were isolated from baechu kimchi. The water fraction, n-hexane fraction, chloroform fraction, ethyl acetate fraction and water insoluble fractions showed no antigenotoxicitie in non-tumoral normal 3T3 cells. Among 5 bacteria isolates from baechu kimchi, two isolates bacteria 1 and 2 strongly inhibited genotoxicity of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in non-tumoral normal 3T3 cells (p<0.05). Bacteria 3, 4 and 5 were also not antigenotoxic.

• Journal of Industrial Technology
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• v.21 no.B
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• pp.11-20
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• 2001

This laboratory study examined the impact of free chlorine residual and pipe material on the formation of biofilm in drinking water distribution pipe surfaces. Result of heterotrophic plate counts(HPC) of the biofilm in the tap water-supplied reactor averaged $2.17{\times}10^5CFU/cm^2$ on PVC and $2.43{\times}10^5CFU/cm^2$ on STS 316, respectively. HPCs on the surface exposed to the tap water containing 0.2mg/L of free chlorinne residual averaged $4.24{\times}10^4CFU/cm^2$ on PVC and $6.54{\times}10^4CFU/cm^2$ on STS 316, respectively. Average of HPC/Total direct counts in the tap water-supplied reactor ranged from 1.08%(PVC) to 1.26%(STS 316) and from 0.38%(PVC) to 0.65%(STS 316) in the reactor supplemented with disinfectant, respectively. No correlation was observed between disinfectant addition and biofilm density. With regard to the biofilm formation, little difference existed between PVC and STS 316. Yellow and red pigmented bacteria were the dominant expressions in bulk fluid, whereas non-pigmented bacteria were found dominant in the biofilm. Pink/red pigmented bacteria were found to be facultative anaerobic, while yellow pigmented bacteria and non-pigmented bacteria were found to be obligate aerobic.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1939-1944
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• 2015

MicroRNA-27a (miR-27a) is deemed to be an oncogene that plays an important role in development of various cancers, and single nucleotide polymorphism (SNP) of miR-27a can influence the maturation or aberrant expression of hsa-miR27a, resulting in increased risk of cancer and poor prognosis for non-small cell lung cancer (NSCLC). This study aimed to assess the effects of rs895819 within miR-27a on susceptibility and prognosis of NSCLC patients in 560 clinical confirmed cases and 568 healthy check-up individuals. Adjusted odds/hazard ratios (ORs/HRs) and 95% confidential intervals (CIs) were calculated to evaluate the association between rs895819 and the risk and prognosis of NSCLC. The results showed that allele A and genotype GG of rs895819 were significantly associated with an increased risk of NSCLC (38.9% vs 30.8%, adjusted OR=1.26, 95%CI=1.23-1.29 for allele G vs A; 18.1% vs 11.7%, adjusted OR=1.67, 95%CI=1.59-1.75 for genotype GG vs AA). Moreover, positive associations were also observed in dominant and recessive models (53.7% vs 49.9%, adjusted OR=1.17, 95%CI=1.13-1.20 for GG/AG vs AA; 18.1% vs 11.7%, adjusted=1.65, 95%CI=1.58-1.73). However, no significant association was found between rs895819 and the prognosis of NSCLC in genotype, dominant and recessive models. These results suggested that miR-27a might be involved in NSCLC carcinogenesis, but not in progression of NSCLC. The allele G, genotype GG and allele G carrier (GG/AG vs AA) of rs895819 might be genetic susceptible factors for NSCLC. Further multi-central, large sample size and well-designed prospective studies as well as functional studies are warranted to verify our findings.