• Journal of Microbiology and Biotechnology
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• 제15권6호
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• pp.1330-1336
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• 2005

Polyhydroxyalkanoic acid (PHA) inclusion bodies were analyzed in situ by $^{13}C$-nuclear magnetic resonance ($^{13}C$-NMR) spectroscopy. The PHA inclusion bodies studied were composed of poly(3-hydroxybutyrate) or poly(3hydroxybutyrate-co-4-hydroxybutyrate), which was accumulated in Hydrogenophaga pseudoflava, and medium-chain-length PHA (MCL-PHA), which was accumulated in Pseudomonas fluorescens BM07 from octanoic acid or 11-phenoxyundecanoic acid (11-POU). The quantification of the $^{13}C$-NMR signals was conducted against a standard compound, sodium 2,2-dimethyl-2-silapentane-5-sulfonate (DSS). The chemical shift values for the in vivo NMR spectral peaks agreed well with those for the corresponding purified PHA polymers. The intracellular degradation of the PHA inclusions by intracellular PHA depolymerase(s) was monitored by in vivo NMR spectroscopy and analyzed in terms of first-order reaction kinetics. The H. pseudoflava cells were washed for the degradation experiment, transferred to a degradation medium without a carbon source, but containing 1.0 g/l ammonium sulfate, and cultivated at $35^{\circ}C$ for 72 h. The in vivo NMR spectra were obtained at $70^{\circ}C$ for the short-chain-length PHA cells whereas the spectra for the aliphatic and aromatic MCL-PHA cells were obtained at $50^{\circ}C\;and\;80^{\circ}C$, respectively. For the H. pseudoflava cells, the in vivo NMR kinetics analysis of the PHA degradation resulted in a first-order degradation rate constant of 0.075/h ($r^{2}$=0.94) for the initial 24 h of degradation, which was close to the 0.050/h determined when using a gas chromatographic analysis of chloroform extracts of sulfuric acid/methanol reaction mixtures of dried whole cells. Accordingly, it is suggested that in vivo $^{13}C$-NMR spectroscopy is an important tool for studying intracellular PHA degradation in terms of kinetics.

• 설비공학논문집
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• 제29권8호
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• pp.429-436
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• 2017

There are three main methods to store heat energy; sensible heat storage, latent heat storage, and thermochemical heat storage. Thermochemical heat storage has the highest storage density among the three methods, so this study focused on the thermochemical heat storage method. Experiments were conducted in this study with Zeolite 13x as thermochemical material in a large-scale reactor with 8 kg of Zeolite 13x. Experiments analyzed storage density of Zeolite 13x with respect to four different heating temperatures ($50^{\circ}C$, $100^{\circ}C$, $150^{\circ}C$, $200^{\circ}C$) in heat storage process. As a result, they showed 40~50 percent of storage efficiency in the experiment. Experiments also revealed that reactions between Zeolite 13x and water vapor were reversible and stable, but efficiency of the system was low, compared with sensible heat storage systems or latent heat storage systems.

• 한국컴퓨터정보학회논문지
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• 제26권12호
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• pp.123-132
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• 2021

봇 넷의 악의적인 행위는 인터넷 서비스 제공자뿐만 아니라 기업, 정부, 그리고 심지어 가정의 일반 사용자에 이르기까지 엄청난 경제적 손실을 끼치고 있다. 본 논문에서는 CTU-13 봇 넷 트래픽 데이터 셋을 사용하여 딥러닝 모델 Convolutional Neural Network(CNN)을 적용한 봇 넷 트래픽 검출에 대한 가능성을 확인하고자한다. 특히 알려진 봇 넷과 알려지지 않은 봇 넷 트래픽에 대해 C&C 서버를 검출하기 위한 봇과 C&C 서버 사이 트래픽, 봇을 검출하기 위한 C&C 통신 이외에 봇이 발생하는 트래픽, 그리고 정상 트래픽을 분류하는 멀티클래스 분류(multi-class classification)를 시도하였다. 성능검증을 위한 지표는 정확도, 정밀도, 재현율, 그리고 F1 점수를 제시하였다. 한편 확장성과 운영을 고려하여 봇 넷 타입 별로 모듈을 적재할 수 있는 스택구조의 봇 넷 검출 시스템을 제안함으로써 실제 네트워크의 적용 가능성을 제시하였다.

• 대한화학회지
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• 제51권4호
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• pp.356-360
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• 2007

sodium ethoxide의 존재하에서 3,5-diaryl-cyclohex-2-en-1-one와 methyl vinyl ketone로부터 5,7-Diaryl- 3,4,6-trihydronaphthalen-2-ones가 합성되었다. 이 생성물은 IR, UV-Visible, 1H-NMR, 13C-NMR 그리고 mass spectral techniques로 구조를 규명하였다. 1H과 13C signals의 피크들은 HSQC spectrum을 찍어 정확히 규명하였다.

• Bulletin of the Korean Chemical Society
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• 제29권1호
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• pp.81-84
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• 2008

In the present study, we report 1H and 13C NMR data of 19 methoxyflavonol derivatives with different substitution patterns on A- and B-ring. In addition, the influence of the methoxy substituents in A- and B-ring on the 1H and 13C NMR chemical shifts is discussed: the 1H and 13C chemical shifts of and the number of methoxyl groups provided information allowing elimination of many structural isomers from consideration and in certain instances greatly simplified structural elucidation.

• 한국결정학회지
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• 제12권3호
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• pp.141-144
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• 2001

Na[Ga(N₃)₄]와 PPh₃의 반응으로부터 이온성 화합물 [Ph₃P(OH)]/sup +/[N₃]/sup -/ (1)이 분리되었다. 화합물1의 구조가 분광학적 방법(¹H-NMR, /sup 13/C{¹H-NMR, IR) 및 X-ray 회절법으로 규명되었다. 화합물1의 결정학 자료 : 사방정계 공간군 P2₁2₁2₁, a = 10.491(4)Å, b=11.603(5)Å, c=13.149(5)Å, Z=4, R(wR₂)=0.0547(0.0978).

• 약학회지
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• 제40권3호
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• pp.293-299
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• 1996

The $^1H$- and $^{13}C$-NMR signals of (20R)-panaxadiol and (20R)-panaxatriol were completely assigned by the extensive application of modern 2D-NMR techniques, $^1H-^1H$ COSY, HMQC and HMBC.

• 한국자기공명학회논문지
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• 제19권1호
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• pp.18-22
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• 2015

The structural geometry of $[N(CH_3)_4]_2CdCl_4$ in a hexagonal phase is studied by $^1H$ MAS NMR, $^{13}C$ CP/MAS NMR, and $^{14}N$ NMR. The changes in the chemical shifts for $^{13}C$ and $^{14}N$ in the hexagonal phase are explained by the structural geometry. In addition, the temperature dependencies of the spin-lattice relaxation time in the rotating frame $T_{1{\rho}}$ for $^1H$ MAS NMR and $^{13}C$ CP/MAS NMR are measured.

• 대한전기학회논문지
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• 제41권5호
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• pp.517-524
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• 1992

In this study, 0.10Pb(SbS11/2TSnS11/2T)OS13T-(0.90-x)PbZrOS13T (0.25 x 0.40) ceramics were fabricated by the atmospheric method. The sintering temperature and time were 1250[$^{\circ}C$] and 2[2hr], respectively. The structureal, dielectric and piezoelectric properties with composition of PbTiOS13T were studied. As the results of XRD ans SEM, the crystal structure of a specimen was rhombohedral, lattice constant and average grain size were decreased with increasing the contents of PbTiOS13T. Relative dielectric constant and Curie temperature were increased with increasing the contents of PbTiOS13T, 0.10PSS-0.40PT-0.50PZ specimen had the highest values of 904 and 265[$^{\circ}C$], respectively. In increasing of PbTiOS13T contents form 25[mol%] to 40[mol%], piezoelectric charge constant and electromechanical coupling factors were increased form 114[pC/N] to 142[pC/N], 17[%] to 24[%] and mechanical quality factor were decreased with increasing the contents of PbTiOS13T. In the 0.10PSS-0.40PT-0.50PZ specimens, those values were 14.2[kV/cm] and 9.43[x10S0-6TC/cmS02T], resectively.

• 통합자연과학논문집
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• 제13권4호
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• pp.128-131
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• 2020

We studied the structure of symmetric group of rubik's cube with oriented face. In conclusion, we have shown that the symmetric group of rubik's cube with oriented face is isomorphic to C46 / 2 × (C37 ≀ S8) × (C210 ≀ S12).