• Journal of Food Hygiene and Safety
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• v.29 no.1
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• pp.67-72
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• 2014

This study investigated the antibacterial effects of GR ethanol extracts (GRE), sodium chlorate (SC) and a combination of GRE and SC (GS) on Brucella abortus (B. abortus). The antibacterial activities of GRE, SC and GS towards B. abortus were evaluated by incubating B. abortus with GRE, SC and GS. Following treatment with GRE, SC and GS, B. abortus survival and intracellular proliferation in macrophages were monitored. In the cellular cytotoxicity assay, GRE, SC and GS are not cytotoxic at concentrations less than $400{\mu}g/ml$, 15 mM and 0.6GS (1 of GS, GRE $1,000{\mu}g/ml$ + SC 30 mM), respectively. The viability of B. abortus was markedly decreased in a dose-dependent manner in all treatment groups. In addition, B. abortus intracellular proliferation within macrophages was significantly reduced in cells treated with GRE ($400{\mu}g/mL$), SC (15 mM) and 0.5GS (GRE $500{\mu}g/mL$ + SC 15 mM) after 48 hr-incubation (GRE, p < 0.01; SC and 0.5GS, p < 0.001). Especially, in the treatment of GS, the synergistic effect of GRE and SC treatment on B. abortus in macrophage was observed. In conclusion, GS is useful as an antibacterial candidate against B. abortus, and can be applied in the field of meat and milk hygiene.

• Investigative Magnetic Resonance Imaging
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• v.11 no.2
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• pp.87-94
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• 2007

Purpose: The purpose of this study was to evaluate the usefulness of fast inversion recovery (FIR) and magnetization-prepared three dimensional gradient echo sequence (3D GRE) T1-weighted sequences for neonatal brain imaging compared with spin echo (SE) sequence in a 3T MR unit. Materials and Methods: T1-weighted axial SE, FIR and 3D GRE sequences were evaluated from 3T brain MR imaging in 20 neonates. The signal-to-noise ratio (SNR) of different tissues was measured and contrast-to-noise ratios (CNR) were determined and compared in each of the sequences. Visual analysis was carried out by grading gray-white matter differentiation, myelination, and artifacts. The Wilcoxon signed ranked test was used for evaluation of the statistical significance of CNR differences between the sequences. Results: Among the three sequences, the 3D GRE had the best SNRs. CNRs obtained with FIR and 3D GRE were statistically superior to those obtained with SE; these CNRs were better on the 3D GRE compared to the FIR. Gray to white matter differentiation and myelination were better delineated on the FIR and 3D GRE than the SE. However, motion artifacts were more commonly observed on the 3D GRE and flow-related artifacts of vessels were frequently seen on the FIR. Conclusion: FIR and 3D GRE are valuable alternative T1-weighted sequences to conventional SE imaging of the neonatal brain at 3T providing superior image quality.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.6
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• pp.1038-1044
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• 2006

Tunneling technique does a role to network authentication or the preservation support of date at high-speed network In order to this, IPsec, SOCKS V5 or GRE tunneling protocol have been using. This paper embodies the offer base of communication service by changing routing route to special IP band for connection interception of harmful service md according to user's needs, by changing routing route to special service at high-speed network. So we measure and analysis action principle of GRE with GRE protocol, the result apply to a service of connection control and authentication base.

• Investigative Magnetic Resonance Imaging
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• v.14 no.1
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• pp.31-40
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• 2010

Purpose : To compare the relative values of various fast breath-hold imaging sequences for superparamagnetic iron-oxide (SPIO)-enhanced hepatic MRI for the assessment of solid focal lesions with a 3T MRI unit. Materials and Methods : 102 consecutive patients with one or more solid malignant hepatic lesions were evaluated by spoiled gradient echo (GRE) sequences with three different echo times (2.4 msec [GRE_2.4], 5.8 msec [GRE_5.8], and 10 msec [GRE_10]) for $T2^*$-weighted imaging in addition to T2-weighted turbo spin echo (TSE) sequence following intravenous SPIO injection. Image qualities of the hepatic contour, vascular landmarks and artifacts were rated by two independent readers using a four-point scale. For quantitative analysis, contrast-to-noise ratio (CNR) was measured in 170 solid focal lesions larger than 1 cm (107 hepatocellular carcinomas, nine cholangiocarcinomas and 54 metastases). Results : GRE_5.8 showed the highest mean points for hepatic contour, vascular anatomy and imaging artifact presence among all of the subjected sequences (p<0.001) and was comparable (p=0.414) with GRE_10 with regard to lesion conspicuity. The mean CNRs were significantly higher (p<0.001) in the following order: GRE_10 ($24.4{\pm}14.5$), GRE_5.8 ($14.8{\pm}9.4$), TSE ($9.7{\pm}6.3$), and GRE_2.4 ($7.9{\pm}6.4$). The mean CNRs of CCCs and metastases were higher than those of HCCs for all imaging sequences (p<0.05). Conclusion : Regarding overall performances, GRE using a moderate echo time of 5.8 msec can provide the most reliable data among the various fast breath-hold SPIO-enhanced hepatic MRI sequences at 3T unit despite the lower CNR of GRE_5.8 compared to that of GRE_10.

• Journal of Life Science
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• v.26 no.12
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• pp.1376-1382
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• 2016

Xylitol is widely used in the food and medical industry. It is produced by the reduction of xylose (lignocellulosic biomass) in the Saccharomyces cerevisiae strain, which is considered genetically safe. In this study, the expression system of the GRE3 (YHR104W) gene that encodes xylose reductase was constructed to efficiently produce xylitol in the S. cerevisiae strain, and the secretory production of xylose reductase was investigated. To select a suitable promoter for the expression of the GRE3 gene, pGMF-GRE3 and pAMF-GRE3 plasmid with GAL10 promoter and ADH1 promoter, respectively, were constructed. The mating factor ${\alpha}$ ($MF{\alpha}$) signal sequence was also connected to each promoter for secretory production. Each plasmid was transformed into S. cerevisiae $SEY2102{\Delta}trp1$, and $SEY2102{\Delta}trp1$/pGMF- GRE3 and $SEY2102{\Delta}trp1$/pAMF-GRE3 transformants were selected. In the $SEY2102{\Delta}trp1$/pGMF-GRE3 strain, the total activity of xylose reductase reached 0.34 unit/mg-protein when NADPH was used as a cofactor; this activity was 1.5 fold higher than that in $SEY2102{\Delta}trp1$/pAMF-GRE3 with ADH1 as the promoter. The secretion efficiency was 91% in both strains, indicating that most of the recombinant xylose reductase was efficiently secreted in the extracellular fraction. In a baffled flask culture of the $SEY2102{\Delta}trp1$/pGMF-GRE3 strain, 12.1 g/l of xylitol was produced from 20 g/l of xylose, and ~83% of the consumed xylose was reduced to xylitol.

• Proceedings of the Korean Society of Computer Information Conference
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• 2022.01a
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• pp.103-105
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• 2022

본 논문에서는 GRE 터널링을 사용한 원격지에서의 BGP 어나운싱 방법에 대해 서술한다. BGP 어나운스를 진행하기 위해서는 고가의 라우터 장비와, 고성능, 고가용성의 네트워크, 자율시스템 망 식별 번호 (AS Number)이 필요하지만 소형 네트워크 운영을 위해 위 요소들을 모두 구비하는 것은 어려운 점이 많기 때문에, BGP Announce를 지원하는 퍼블릭 클라우드와의 GRE 라우팅을 사용해서 저비용으로 안정적인 BGP Announce를 하는 방법과, 이에 필요한 소프트웨어적 구성에 대해서 기술한다.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.23 no.2
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• pp.13-26
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• 2010

Objectives : The present study was conducted to evaluate the anti-inflammatory effects of the Gamroeum water extracts (GRE) in vivo and in vitro. Methods : The effects of GRE on anti-inflammation were measured by production of NO, $PGE_2$ (Prostaglandin $E_2$), iNOS (inducible Nitric Oxide Synthase), COX-2, $NF{\kappa}B$ (Nuclear Factor kappa B), TNF-$\alpha$ (Tumor Necrosis Factor-alpha) and IL-$1{\beta}$ (Interleukin-$1{\beta}$), IL-6 in Raw 264.7 macrophage cells stimulated with LPS. Results : 1. In machrophage cells, LPS displayed significant stimulatory effects on the production of NO and $PGE_2$. However, GRE showed significant inhibitory effects on NO and $PGE_2$ release. The level of NO and $PGE_2$ was decreased by GRE in a concentration dependent manner as compared with LPS only group. 2. Immunoblot analysis verified that LPS stimulation significantly increased the iNOS and COX-2 protein level, but GRE suppressed the induction of iNOS and COX-2 protein at a concentration dependent manner. 3. GRE reduced the elevated production of TNF-$\alpha$, IL-$1{\beta}$ and IL-6 by LPS. Moreover, the inhibitory effects of GRE was occurred in a dose-dependent manner. 4. GRE significantly reduced the expression of NF-${\kappa}B$ protein in nuclear fraction. 5. GRE effectively inhibited the increases of hind paw skin thicknesses and inflammatory cell infiltrations induced by carrageenan treatment. It, therefore, considered that GRE will be favorably inhibited the acute edematous inflammations. Conclusions : These results indicated that GRE could have anti-inflammatory capacity by inhibiting the production of NO, $PGE_2$ and cytokines in vitro and by reducing the formation of carrageenan-induced paw edema in vivo. Moreover, inhibitory effects of GRE on the macrophage activation were attributable to the reduction of some of inflammatory factors by inhibiting iNOS and COX-2 through the suppression of NF-${\kappa}B$.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.279-280
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.186-189
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• 2001

In a precise control system, the Lu-Gre friction model has often been used to describe the nonlinear friction. For the XY table system with this friction model, we identified the friction parameters and designed nonlinear observer. The nonlinear friction effects could be removed within appropriate position tracking errors and control inputs through experiments. Also, we designed the nonmodel-based SMC system to compensate the nonlinear friction. Through experiments, it is shown that this method has the similar performance compared with the nonlinear observer system and is useful when friction parameters are hard to identify except the problem of input chattering.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.5
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• pp.508-513
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• 2009

Friction is an important factor for precise position tracking control of servo systems. Servo systems with highly nonlinear friction are sensitive to the variation of operating condition. To overcome this problem, we use the LuGre friction model which can consider dynamic characteristics of friction. The LuGre friction model is used as a feed-forward compensator to improve tracking performance of servo systems. The parameters of the LuGre friction model are identified through experiments. The experimental result shows that the tracking performance of servo systems with higherly nonlinear friction can be improved by using feed-forward friction compensation.