• Title/Summary/Keyword: Q&A System

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The Development of Evaluation Indicators for the Performance of Defense Core-Technology R&D Projects Using SMR/AHP (SMR/AHP 기법을 활용한 국방핵심기술 연구개발사업 성과평가지표 개발)

  • Lee, Hyung-Jun;Kim, Chan-Soo;Kim, Woo-Je
    • Journal of the Korea Institute of Military Science and Technology
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    • v.12 no.1
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    • pp.70-79
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    • 2009
  • Currently, the investment on Research and Development(R&D) for defense core technology is continuously increasing to maintain advanced country's R&D level. In accordance with this trend, the national defense R&D investment management system is being more strengthening, and importance of performance evaluation is being emphasized more and more. However, the existing indicators of performance evaluation for defense core technology R&D is limited in efficient management because of the qualitative evaluation items and subjective allocation of points. In this paper, we developed a novel indicator for defense core technology R&D performance evaluation through domestic and foreign related literature and inquiry, brainstorming, and analysis techniques by Stepwise Multiple linear Regression(SMR) and Analytic Hierarchy Process(AHP). And we verified effectiveness of proposed indicators of performance evaluation by comparing with the existing evaluation indicators. Our proposed indicators for performance evaluation will create superiority performance on defense R&D fields.

Piezoelectric Characteristics of PZT-PSN Ceramics Depending on WO3Addition (PZT-PSN 세라믹스의 WO3의 첨가량에 따른 압전 특성)

  • 배숙희;김성곤;김철수;이경화;이상렬
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.9
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    • pp.794-797
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    • 2002
  • Piezoelectric properties of PZT-PSN ceramics were investigated as a function of WO$_3$ addition from 0 wt% to 6.0 wt%. The dielectric and piezoelectric characteristics of PZT-PSN ceramics have been investigated at different calcination (80$0^{\circ}C$~90$0^{\circ}C$) and sintering (110$0^{\circ}C$~130$0^{\circ}C$) temperatures. The grain size was increased with the addition of WO$_3$and the sintering temperatures. Anisotropic properties of electromechanical coupling coefficient and piezoelectric coefficient are proven to be dependent on processing temperatures and amount of addition. At the specimen with 0.6 wt% WO$_3$ addition, using calcination temperature of 80$0^{\circ}C$ and sintering temperature of 110$0^{\circ}C$ , mechanical quality factor(Q$_{m}$) and electromechanical coupling coefficient(k$_{p}$) showed the excellent results of 1560 and 0.48, respectively Experimental results indicated that the PZT-PSN system ceramics with WO$_3$impurity could be effectively used for the microtransformer and actuator applications, etc.etc.

Data-Base of Statistical Parameters from PD generated in Solid Insulation (고체절연재료에서 발생하는 부분방전 특성량의 Data-Base 구축)

  • Kang, S.H.;Lee, H.G.;Park, Y.G.;Kim, W.S.;Lee, Y.H.;Park, J.N.;Lim, K.J.
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.1927-1929
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    • 2000
  • PD indicates the inception and progress of degradation of solid insulation system, so it has been used to determine degradation of insulation. PD provides means for detection and recognition of defects. However, there is still marked difficult to recognize defects by PD methods. In this paper, we investigated properties of PD in solid insulation by using statistical method with surface discharge, electrical tree and void discharge with source of discharge, we used statistical parameters of PD distributions specified such as $H_n(q)$, $H_{an}(\phi)$, $H_n(\phi)$, $H_a(\phi)$. The parameters induced from its specified distributions are average discharge, average repetition rate, Skewness, Kurtosis, asymmetry and correlation. From the parameters, we classified PD patterns and built up DB(data-base).

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Optimal Design of Slider for Stable Flying Characteristics using $4{\times}1$ Near-field Probe Array

  • Jung, Min-Su;Hong, Eo-Jin;Park, Kyoung-Su;Park, No-Cheol;Yang, Hyun-Seok;Park, Young-Pil;Lee, Sung-Q;Park, Kang-Ho
    • Transactions of the Society of Information Storage Systems
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    • v.2 no.1
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    • pp.65-70
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    • 2006
  • In the information storage development, the trend of the storage device is to increase the recording density. Among such an effort, near-field probe recording is spotlighted as a method of high increasing recording density. For the successfully embodiment of storage device, the actuating mechanism of near-field probe is essentially designed. In this paper, we suggest the slider similar with conventional HDD and design the slider using near-field probe for the purpose of applying the slider in order to control gap between probe and media. The most important object of slider design is to guarantee the flying ability and stability. For achievement of these design objects, we perform two step of optimal design process. The media is supposed to model as random displacement, which is only considered roughness of disk surface. The design slider is analyzed with dynamic state in assumed media. At this process, the optimal model is confirmed to stable flying stability.

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Effect of Non-indigenous Bacterial Introductions on Rhizosphere Microbial Community

  • Nogrado, Kathyleen;Ha, Gwang-Su;Yang, Hee-Jong;Lee, Ji-Hoon
    • Korean Journal of Environmental Agriculture
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    • v.40 no.3
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    • pp.194-202
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    • 2021
  • BACKGROUND: Towards achievement of sustainable agriculture, using microbial inoculants may present promising alternatives without adverse environmental effects; however, there are challenging issues that should be addressed in terms of effectiveness and ecology. Viability and stability of the bacterial inoculants would be one of the major issues in effectiveness of microbial pesticide uses, and the changes within the indigenous microbial communities by the inoculants would be an important factor influencing soil ecology. Here we investigated the stability of the introduced bacterial strains in the soils planted with barley and its effect on the diversity shifts of the rhizosphere soil bacteria. METHODS AND RESULTS: Two different types of bacterial strains of Bacillus thuringiensis and Shewanella oneidensis MR-1 were inoculated to the soils planted with barley. To monitor the stability of the inoculated bacterial strains, genes specific to the strains (XRE and mtrA) were quantified by qPCR. In addition, bacterial community analyses were performed using v3-v4 regions of 16S rRNA gene sequences from the barley rhizosphere soils, which were analyzed using Illumina MiSeq system and Mothur. Alpha- and beta-diversity analyses indicated that the inoculated rhizosphere soils were grouped apart from the uninoculated soil, and plant growth also may have affected the soil bacterial diversity. CONCLUSION: Regardless of the survival of the introduced non-native microbes, non-indigenous bacteria may influence the soil microbial community and diversity.

3D-QSAR, Docking and Molecular Dynamics Simulation Study of C-Glycosylflavones as GSK-3β Inhibitors

  • Ghosh, Suparna;Keretsu, Seketoulie;Cho, Seung Joo
    • Journal of Integrative Natural Science
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    • v.13 no.4
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    • pp.170-180
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    • 2020
  • Abnormal regulation, hyperphosphorylation, and aggregation of the tau protein are the hallmark of several types of dementia, including Alzheimer's Disease. Increased activity of Glycogen Synthase Kinase-3β (GSK-3β) in the Central Nervous System (CNS), increased the tau hyperphosphorylation and caused the neurofibrillary tangles (NFTs) formation in the brain cells. Over the last two decades, numerous adenosine triphosphate (ATP) competitive inhibitors have been discovered that show inhibitory activity against GSK-3β. But these compounds exhibited off-target effects which motivated researchers to find new GSK-3β inhibitors. In the present study, we have collected the dataset of 31 C-Glycosylflavones derivatives that showed inhibitory activity against GSK-3β. Among the dataset, the most active compound was docked with the GSK-3β and molecular dynamics (MD) simulation was performed for 50 ns. Based on the 50 ns MD pose of the most active compound, the other dataset compounds were sketched, minimized, and aligned. The 3D-QSAR based Comparative Molecular Field Analysis (CoMFA) model was developed, which showed a reasonable value of q2=0.664 and r2=0.920. The contour maps generated based on the CoMFA model elaborated on the favorable substitutions at the R2 position. This study could assist in the future development of new GSK-3β inhibitors.

The Inhibitory Effect of NLRP3 Deficiency in Hepatocellular Carcinoma SK-Hep1 Cells

  • Choi, Wonhyeok;Cho, Hyosun
    • Microbiology and Biotechnology Letters
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    • v.49 no.4
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    • pp.594-602
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    • 2021
  • The NLRP3 (nucleotide-binding domain, leucine-rich repeat family pyrin domain containing 3) inflammasome plays an important role in the initiation of inflammatory responses, through the recognition of pathogen-associated molecular patterns and tumor progression, including tumor growth and metastasis. In this study, we examined the effects of defective NLRP3 on the growth, migration, and invasiveness of hepatocellular carcinoma (HCC) SK-Hep1 cell. First, HCC SK-Hep1 cells were transfected with human NLRP3 targeting LentiCRISPRv2 vector using the CRISPR-Cas9 system, and NLRP3 deficiency was confirmed by RT-qPCR and western blotting. NLRP3 deficient SK-Hep1 cells showed delayed cell growth and decreased protein expression of PI3K, p-AKT, and pNF-κB when compared to NLRP3 complete SK-Hep1 cells. In addition, NLRP3 deficiency arrested the cell cycle at G1 phase through an increase in p21 and a reduction in CDK6. NLRP3 deficient SK-Hep1 cells also showed significantly delayed cell migration, invasion, and wound healing. The expression of epithelial-mesenchymal transition signaling molecules, such as N-cadherin and MMP-9, was found to be dramatically decreased in NLRP3 deficient SK-Hep1 cells compared to NLRP3 complete SK-Hep1 cells.

Analysis of QRS-wave Using Wavelet Transform of Electrocardiogram (웨이블릿 변환을 이용한 심전도의 QRS파 신호 분석)

  • Choi, Chang-Hyun;Kim, Yong-Joo;Kim, Tae-Hyeong;Ahn, Yong-Hee;Shin, Dong-Ryeol
    • Journal of Biosystems Engineering
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    • v.33 no.5
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    • pp.317-325
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    • 2008
  • The electrocardiogram (ECG) measurement system consists of I/O interface to input the ECG signals from two electrodes, FPGA (Field programmable gate arrays) module to process the signal conditioning, and real time module to control the system. The algorithms based on wavelet transform were developed to remove the noise of the ECG signals and to determine the QRS-waves. Triangular wave tests were conducted to determine the optimal factors of the wavelet filter by analyzing the SNRs (signal to noise ratios) and RMSEs (root mean square errors). The hybrid rule, soft method, and symlets of order 5 were selected as thresholding rule, thresholding method, and mother wavelet, respectively. The developed wavelet filter showed good performance to remove the noise of the triangular waves with 10.98 dB of SNR and 0.140 mV of RMSE. The ECG signals from a total of 6 subjects were measured at different measuring postures such as lying, sitting, and standing. The durations of QRS-waves, the amplitudes of R-waves, the intervals of RR-waves were analyzed by using the finite impulse response (FIR) filter and the developed wavelet filter. The wavelet filter showed good performance to determine the features of QRS-waves, but the FIR filter had some problems to detect the peaks of Q and S waves. The measuring postures affected accuracy and precision of the ECG signals. The noises of the ECG signals were increased due to the movement of the subject during measurement. The results showed that the wavelet filter was a useful tool to remove the noise of the ECG signals and to determine the features of the QRS-waves.

Synthesis of Glycosides by Transglycosylation of $\alpha$-Amylase from Soluble Starch in Water-Organic Two Phase System (전분을 기질로 한 이상계에서 Amylase의 당전이반응에 의한 배당체의 합성)

  • 박종이;이재동;이태호;장경립
    • Korean Journal of Microbiology
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    • v.35 no.1
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    • pp.1-6
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    • 1999
  • Benzylalcohol-$\alpha$-glucoside (BG) was synthesized from soluble starch by transglycosylation of $\alpha$-amylase. Transglycosylation in water-organic two phase system containing 1% soluble starch as a glycosyl donor, 90% benzylalcohol as a glycosyl acceplor, 10% citrate buffer solulion (0.1 M, pH 5.0), and 10 unit of $\alpha$-amylase (Aspergilllw oryzae) was showed highcst efficiency. About 4 mg BG was obtained from 10 mg starch in reaction for 80 hrs at $40^{\circ}C$. Initially benzylalcohol-$\alpha$-maltoside Q3M) was major product, but as the reaction proceeded, it was hydrolyzed to glucose and BG. Finally the product of transglycosylation by $\alpha$-amylase was only BG. The both products did not show reducing powcr and hydrolyzed by $\alpha$-glucosidase and $\alpha$-amylase, respectively. The molecular wcights of both were estimated to be 270 and 432 by ES1-Mass, respectively.

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Microbial Community Analysis in the Wastewater Treatment of Hypersaline-Wastewater (고농도 염분폐수의 정화능이 우수한 기능성 미생물 커뮤니티의 군집 분석)

  • Lee, Jae-Won;Kim, Byung-Hyuk;Park, Yong-Seok;Song, Young-Chae;Koh, Sung-Cheol
    • Microbiology and Biotechnology Letters
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    • v.42 no.4
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    • pp.377-385
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    • 2014
  • In this study, a wastewater treatment system for hypersaline wastewater utilizing the Hypersaline Wastewater Treatment Community (HWTC) has been developed. The hypersaline wastewater treatment efficiency and microbial community of the HWTC were investigated. The average removal efficiencies of chemical oxygen demand were 84% in an HRT of 2.5 days. Microbial community analysis, by denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rRNA gene fragments and 16S rRNA gene clone library, revealed community diversity. The 16S rRNA gene analysis of dominant microbial bacteria in 4% hypersaline wastewater confirmed the presence of Halomonas sp. and Paenibacillus sp. Phylogenetic analysis suggested that the taxonomic affiliation of the dominant species in the HWTC was ${\gamma}$-proteobacteria and firmicutes. These results indicate the possibility that an appropriate hypersaline wastewater treatment system can be designed using acclimated sludge with a halophilic community.