• Journal of Biomedical Engineering Research
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• v.25 no.3
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• pp.227-233
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• 2004

In this paper, it is proposed that the four channel electrode arrangement at a frontal lobe and the noise reduction method using a JADE for the EEG biofeedback system. The proposed electrode arrangement is based on the retina-cornea dipole model. Using JADE and signals which are acquired by the proposed arrangement, four independent components are separated. To estimate a pure EEG component among four components, it is measured that a ratio of alpha wave to the whole signal and then the component that has a maximum value is considered as a pure EEG which the noise is eliminated. As a result of experiments, the proposed methods are effective in reduction of noises during acquisition of the EEG.

• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.507-513
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• 2000

A bacteriocin-producing organism, Enterococcus sp. T7, was isolated from human fecal samples. Bacteriocin T7, named tentatively as the bacteriocin, was produced by Enterococcus sp. T7 and it inhibited some strains of Lactobacillus. Staphylococcus, Enterococcus, and Streptococcus, but not all the lactococci and gram-negative bacteria tested. Bacteriocin T7 inhibited the growth of Listeria monocytogenes Scott A, but the degree of inhibition was less than those for other sensitive gram-positive vacteria. Bacteriocin T7 in MRS broth started to produce at the middle of the exponential growth phase and the inhibitory activity reached its maximum level during the stationary growth phase. Bacteriocin T7 was stable against heat treatments, pH variations (pH 2-10), and exposure to organic solvents. The molecular weight of bacteriocin T7 was estimated to be 6.500 Da by SDS-PAGe. All these facts, including physico-chemical stabilities, small molecular size, and inhibition of Kisteria monocytogenes, indicate that bacteriocin T7 is likely to be a member of the class IIa bacteriocins.

• Journal of Biomedical Engineering Research
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• v.28 no.3
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• pp.417-422
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• 2007

In this study, we investigated spatio-temporal eye-hand coordination by the "Global effect paradigm", a target-distracter configuration Global effect is observed a variety of visual tasks, for example, during rapid automatic tracking, scanning for target detail, and the comparison of target configurations. Global effect used to investigate eye-hand coordination with a task that presents a target close to a distracter. Eight young subjects participated in the experiments. The experiments consist of using a distracter less eccentric than the targe1 and using a distracter more eccentric than target. Each experiment consist of tasks which are making reference, pointing the target with watching visual stimulation(saccade) and pointing the target. The subject's task was to move towards the target as quickly as possible. We measured the eye movement by using EOG and the hand movement by using NDI Optotrak system. This study shows that eye and hand movement exists for global effect paradigm in spatio-temporal coordination.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.778-782
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• 2007

This study assessed the effects of the antimicrobial substances sulforaphane, grapefruit seed extracts (GSE), and reuterin on the expression of Salmonella HilA and InvF virulence gene using a LacZY assay (${\beta}$-galactosidase assay) with hilA:lacZY and invF:lacZY fusion strains of Salmonella typhimurium SL1344. Salmonella was grown for 8 hr at $37^{\circ}C$ in the presence of diluted antimicrobial substances ($2\;{\mu}g/mL$ sulforaphane, $20\{\mu}g/mL$ GSE, and 0.26 mM reuterin) at concentrations that did not inhibit the cellular growth of Salmonella. Sulforaphane inhibited the expression of HilA and InvF by 50-90 and 20-80%, respectively. GSE also inhibited the expression of both genes, but to a lesser degree. Among the 3 antimicrobial substances, reuterin showed the least inhibition, which was abolished after 3-4 hr. None of the antimicrobial substances inhibited the ${\beta}$-galactosidase enzyme activity of S. typhimurium. The assay used in this study represents a very sensitive method for screening bioactive substances that inhibit the expression of virulence genes in Salmonella.

• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.457-462
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• 2003

The complete nucleotide sequence of a plasmid, pMG1, isolated from Bifidobacterium longum MG1 has been determined. This plasmid, composed of 3,862 base pairs with 65.1% of G+C content. harbors two major open reading frames (ORF) encoding putative proteins of 29 kDa (ORF I) and 71 kDa (ORF II). ORF I showed relatively high amino acid sequence homology with replication proteins of other plasmids from Gr Im-positive and -negative bacteria. Upstream of ORF I, four sets of tandem repeat sequences resembling the iteron structure of related plasmids were found. S1 endonuclease treatment and Southern blot analysis revealed that pMG1 accumulates single-stranded DNA (ssDNA) intermediate, which indicate i the rolling circle replication (RCR) mechanism of this plasmid. Homology search indicated that ORF II encodes plasmid mobilization protein, and the presence of highly conserved oriT sequence in the upstream of this gene supported this assumption. RT-PCR showed that only ORF I is expressed in vivo. Based on these results, pMG 1 was exploited to construct a shuttle vector, pBES2. It was successfully transformed into Bifidobacterium and maintained stably.

• Journal of Microbiology and Biotechnology
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• v.28 no.5
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• pp.688-696
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• 2018

Ginseng and probiotics have anti-obesity effects in mice fed a high-fat diet (HFD). Absorption of ginsenoside and colonization of probiotics occur in the intestine. In this study, a mixture of fermented ginseng and two probiotics, Bifidobacterium longum BORI and Lactobacillus paracasei CH88, was administered to HFD-fed mice for 9 weeks. The mixture significantly suppressed weight gain (p < 0.05, n = 8) and lipid deposition in the liver and adipose tissues as well as increased the mice's food intake. The adipocyte size of the adipose tissue was significantly decreased in the mixture-fed group, especially when 0.5% fermented ginseng and $5{\times}10^8/ml$ of the two probiotics were used (p < 0.05, n = 10). The expression of TNF-${\alpha}$ in adipose tissue was efficiently downregulated in the mixture-fed group (p < 0.05, n = 4). The supplement also improved the mice's fasting blood glucose levels (p < 0.05, n = 8) and total cholesterol feces excretion (p < 0.05, n = 8). The mixture of fermented ginseng and B. longum BORI and L. paracasei CH88 could have an anti-obesity effect and suppress lipid deposit in the liver and adipose tissues.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.4
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• pp.16-23
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• 2009

Driving simulators are useful tools not only to test the components of future cars but also to evaluate the telematics service and HMI (Human-Machine Interface). However driving simulators cannot be implemented to test and evaluate the telematics service system because the GPS (Global Positioning System) which contains basic functional support for the telematics module do not work in the VR (virtual reality) environment. This paper presents a method to implement telematics service to a driving simulator by developing the GPS simulator which is able to emulate GPS satellite signals consist of NMEA-0183 protocol and RS232C communication standards. It is expected that the driving simulator with the GPS simulator can be used to study HMI and human-factor evaluations of the commercial telematics system to realize the HiLES (Human-in-the-Loop Evaluation System).

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.8
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• pp.136-143
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• 2007

A improved current controller with reference modification part that has both fast transient response in transient state and high accuracy in steady state is proposed. In this scheme, a improved reference modification part is used to synchronous frame PI controller for the fast transient state. The transient response of current controller is seriously deteriorated in high back e.m.f.(electromotive force) due to the lack of DC link control voltage. This paper is proposed that the improved reference modification part is compared with voltage limit and reference voltage.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.8
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• pp.151-159
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• 2007

This paper proposes a improved decoupling current control algorithms using a compensator to enhance the robustness to the stator inductance error. And the compensator composed from a d-axis current error for sensing change of the real stator inductance can match the estated stator inductance to the real stator inductance. A great advantage of this algorithms is more robust than feedforward decoupling current control or dynamic decoupling control. So it looks suitable to the practical applications where the exact parameters are unknown. Though simulation and experimental results with 1[kW] prototype PMSM and TMS320F2812 board for motor control, we show that the proposed controller achieves the desired performance.

• Journal of Microbiology and Biotechnology
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• v.10 no.2
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• pp.143-146
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• 2000

This study was conducted to compare the cellular fatty acid composition and genotypic analysis of Bifidobacterium longum MK-G7 originated from Koreans with other commercial type strains of bifidobacteria. The cellular fatty acid of Bif. longum MK-G7 was shown to be composed of $C_{160FAME},C_{181\;c18DMA},C_{18.1\;CIS9\; FAME},C_{14.0FAME},C_{19\;0cye9,10 DMA},Feature7(C_{17.2 FAME), and Feature 10(C_{181\; Cll/t9/t6 FAME}$. Bif. longum MK-G7 showed 99.9% homology and the highest relatedness with Bif. longum ATCC 15707 type strain. Both Bif. longum MK-G7 and Bif. longum ATCC 15707 showed 153 bp products on RAPD (randomly amplified polymorphic DNA) analysis, however, they showed quite different band patterns on PFGE (pulsed-field gel electrophoresis) analysis. Consequently, our present study showed that Bif. longum MK-G7 was different from any commercial type strains of Bif. longum tested.