• 방재와보험
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• s.144
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• pp.18-23
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• 2012

• The Science & Technology
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• s.513
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• pp.18-22
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• 2012

• 방재와보험
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• s.157
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• pp.18-22
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• 2015

• Women's Health Nursing
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• v.30 no.1
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• pp.18-25
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• 2024

• Proceedings of the KIEE Conference
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• 2002.11a
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• pp.94-96
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• 2002

The $0.97MgTiO_3-0.03SrTiO_3$ ceramics with $B_2O_3$(10wt%) were prepared by the conventional mixed oxide method. The structural properties were investigated with sintering temperature by XRD and SEM. According to the X-ray diffraction patterns of the $0.97MgTiO_3-0.03SrTiO_3$ ceramics with $B_2O_3$(10wt%), the ilmenite $MgTiO_3$ and perovskite $SrTiO_3$ structures were coexisted and secondary phase $MgTi_2O_5$ were appeared. Increasing the sintering temperature. the grain size was increased. In the case of $0.97MgTiO_3-0.03SrTiO_3$ ceramics with $B_2O_3$(10wt%), dielectric constant, quality factor and temperature coefficient of resonant frequency were $13.52{\sim}18.13,\;32750{\sim}51736GHz$, $-15.78{\sim}25.64ppm/^{\circ}C$, respectively.

• 정보화사회
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• s.169
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• pp.28-31
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• 2004

우리나라 정보통신은 불과 20여년만에 국가경쟁력을 선도하는 성장엔진으로 자리매김하였다. 최근 발표된 2004년 IMD의 국가경쟁력 평가 결과 우리나라 20대 강점 분야 중 IT관련 사항이 4개“나 포함되어 있으며, 아울러 IT산업은 연평균 GDP 성장률 8.3%를 상회하는 18.8%(‘98-’03)의 고도성장을 이루었고, 우리나라 전체 수출의 30%(‘03: 1,938억불 중 576억불)를 IT수출이 차지하는 등 경제발전을 주도하는 국가 주력산업으로 부상하였다.

• Journal for History of Mathematics
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• v.10 no.2
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• pp.11-23
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• 1997

Category theory gives a convenient language for the study of mathematical structures besides its own study. In this paper, we investigate how the abstract structure theory emerged in 1930s affects the study in Topology and eventually becomes a rudiment for the category theory. Moreover, various extensions and universal mapping problems were put in their proper perspective as reflections by the category theory and by its duality principle, coreflections become an interesting subject in Topology, both of which give rise to a new discipline of the categorical topology.

• Journal of Microbiology and Biotechnology
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• v.23 no.7
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• pp.905-912
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• 2013

A novel species, Metschnikowia cibodasensis, is proposed to accommodate eight strains (ID03-$0093^T$, ID03-0094, ID03-0095, ID03-0096, ID03-0097, ID03-0098, ID03-0099, and ID03-0109) isolated from flowers of Saurauia pendula, Berberis nepalensis, and Brunfelsia americana in Cibodas Botanical Garden, West Java, Indonesia. The type strain of M. cibodasensis is ID03-$0093^T$ (= NBRC $101693^T$ =UICC $Y-335^T$ = BTCC-$Y25^T$). The common features of M. cibodasensis are a spherical to ellipsoidopedunculate shaped ascus, which contains one or two needle-shaped ascospores, and lyse at maturity. Asci generally develop directly from vegetative cells but sometimes from chlamydospores. The neighbor-joining tree based on the D1/D2 domain of nuclear large subunit (nLSU) ribosomal DNA sequences strongly supports that M. cibodasensis (eight strains) and its closest teleomorphic species, M. reukaufii, are different species by a 100% bootstrap value. The type strain of M. cibodasensis, ID03-$0093^T$, differed from M. reukaufii NBRC $1679^T$ by six nt (five substitutions and one deletion) in their D1/D2 region of nLSU rDNA, and by 18 nt (five deletions, four insertions, and nine substitutions) in their internal transcribed spacer regions of rDNA, respectively. Four strains representative of M. cibodasensis (ID03-$0093^T$, ID03-0095, ID03-0096, and ID03-0099) showed a mol% G+C content of $44.05{\pm}0.25%$, whereas that of M. reukaufii NBRC $1679^T$ was 41.3%. The low value of DNA-DNA homology (5-16%) in four strains of M. cibodasensis and M. reukaufii NBRC $1679^T$ strongly supported that these strains represent a distinct species.

• Food Science of Animal Resources
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• v.21 no.1
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• pp.64-70
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• 2001

The extraction procedure and HPLC condition were modified to analyze the residues of oxytetracycline, sulfamethoxazole and chloramphenicol in pork, simultaneously. The antibacterial agents in pork were extracted with 0.02M EDTA-Mcilivine buffer:ethanol:acetonitrile (5:3:2). After the removal of fat with n-hexane, the extracts were evaporated and purified with Sep-pak $C_{18}$ cartridge column using 0.01M oxalic acid 0.1% (v/v) triethylamine (TEA) in acetonitrile. The peak of antibacterial agents was detected with $\mu$ Bondapak C18 column, UV detector (280nm) and 0.01M oxalic acid: methanol: acetonitrile (7.5:2.0:0.5). Detection limits for three antibacterial standards were 0.03 ppm. Calibration curves were linear between 0.03 and 2.0 ppm (R$^2$>0.999). When spiked the level of 1.0 ppm of oxytetracycline, sulfamethoxazole and chloramphenicol into meats, the recoveries from meats were 77.3%, 79.7% and 59.3%, respectively. These results showed that the modified extraction method provided good analytical resolution and the recoveries of the above antibacterial agents in meats.

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.292-294
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• 1993

Three derivatives of poly(ethylenimine) (PEI) are prepared by Ni(II)-template condensation with glyoxal(GO): PEI[Ni(II)-GO]$_{0.08}$ (1), PEI[Ni(II)-GO]$_{0.03}$ (2), and lau$_{0.18}$PEI[Ni(II)-GO]$_{0.03}$ (3). The contents of Ni(II)-macrocyclic center of 1-3 are 8%, 3%, or 3%, respectively, of the monomer residues, and 18% of monomer residues for 3 are laurylated. The pH profiles for k$_{cal}$ and k$_m$ for the deacylation of 4-carboxy-2-nitrophenyl acetate are measured. The relative magnitude of the parameters for 1-3 and different shapes of the pH profiles for 1-3 are explained in terms of the electrostatic and the hydrophobic effects exerted by the metal centers and lauryl groups. For the artificial metalloenzymes built on PEI, therefore, the ionization of functional groups and the affinity toward counter-anions can be controlled by adjusting charge density and the content of hydrophobic groups.