• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.08a
• /
• pp.169-169
• /
• 2012

The high-temperature superconductor YBa2Cu3O7-x (YBCO) have attached attentions because of a high superconducting transition temperature, low surface resistance, high superconducting critical current density (Jc), and superior superconducting capability under magnetic field. Moreover, the Jc of YBCO superconductors can be enhanced by adding impurities to the YBCO films for vortex-pinning. Understanding and controlling pinning centers are key factors to realize high Jc superconductors. We synthesized vertically-aligned ZnO nanorods on SrTiO3 (STO) substrates by catalyst-free metal-organic chemical vapor deposition (MOCVD), and subsequently, deposited YBCO films on the ZnO nanorods/STO templates using pulsed laser deposition (PLD). The various techniques were used to analyze the structural and interfacial properties of the YBCO/ZnO nanorods/STO hybrid structures. SEM, TEM, and XRD measurements demonstrated that YBCO films on ZnO nanorods/STO were well crystallized with the (001) orientation. EXAFS measurements from YBCO/ZnO nanorods/STO at Cu K edge demonstrated that the local structural properties around Cu atoms in YBCO were quite similar to those of YBCO/STO.

• 한국생물공학회:학술대회논문집
• /
• 2000.11a
• /
• pp.623-625
• /
• 2000

Bacteriocin-producing lactic acid bacteria was isolated from Kimchi using MRS as selective media and Lactobacillus delbruekii subsp. delbruekii as an indicator strain. Strain JC-3 was tentatively identified as Lactococcus latis subsp. lactis through the API test and the bacteriocin produced by JC-3 showed the inhibitory activity against Grampositive pathogens and other lactic acid bacteria. The antimicrobial substance was inactivated by Protamax, Aroase AP-10, Neutrase, R-AMANO and was confirmed to be heating at $100^{\circ}C$. However, it was lost at high pH values showed the highest bacteriocin activity at a culture temperature of $30^{\circ}C$. The bacteriocin was partially purified by ammonium sulfate precipitation, Sep-pak $C_{18}$ cartridge. The apparent molecular mass of the bacteriocin was about 8 Kda, which was determined through the direct detection of bactericidal activity using SDS -PAGE.

• Progress in Superconductivity and Cryogenics
• /
• v.18 no.1
• /
• pp.1-5
• /
• 2016

Field and temperature dependence of the critical current density, Jc, were measured for both un-doped and carbon doped $MgB_2/Nb/Monel$ wires manufactured by Hyper Tech Research, Inc. In particular, carbon incorporation into the $MgB_2$ structure using malic acid additive and a chemical solution method can be advantageous because of the highly uniform mixing between the carbon and boron powders. At 4.2 K and 10 T, Jc was estimated to be $25,000-25,300Acm^{-2}$ for the wire sintered at $600^{\circ}C$ for 4 hours. The irreversibility field, $B_{irr}$, of the malic acid doped wire was approximately 21.0 - 21.8 T, as obtained from a linear extrapolation of the J-B characteristic. Interestingly enough, the Jc of the malic acid doped sample exceeds $10^5Acm^{-2}$ at 6 T and 4.2 K, which is comparable to that of commercial Nb-Ti wires.

• Journal of Microbiology
• /
• v.44 no.2
• /
• pp.171-176
• /
• 2006

A strictly aerobic, non-motile, ovoid-shaped Alphaproteobacteria, designated strain $JC2049^T$ was isolated from a tidal flat sediment sample. The results of 16S rRNA gene sequence analysis indicated that this isolate belonged to the genus Thalassobius, with a sequence similarity of 96.9-97.3% to other valid Thalassobius spp. The cells required 1-7% NaCl for growth (optimum 2%) and accumulated $poly-\beta-hydroxybutyrate$. Nitrite was reduced to nitrogen, but nitrate was not reduced to nitrite. No genetic potential for aerobic anoxygenic photosynthesis was detected. The primary isoprenoid quinone (Ubiquinone-10), predominant cellular fatty acids $(C_{18:1}{\omega}7c,\;11\;methyl\;C_{18:1}\omega7c\;and\;C_{16:0})$ and DNA G+C content (61 mol %) were all consistent with the assignment of this isolate to the genus Thalassobius. Several phenotypic characteristics clearly distinguished our isolate from other Thalassobius species. The degree of genomic relatedness between strain $JC2049^T$ and other Thalassobius species was in a range of 20-43 %. The polyphasic data presented in this study indicates that our isolate should be classified as a novel species within the genus Thalassobius. The name Thalassobius aestuarii sp. novo is therefore proposed for this isolate; the type strain is $JC2049^T(=IMSNU\;14011^T=KCTC\;12049^T=DSM\;15283^T)$.

• Journal of Microbiology
• /
• v.35 no.1
• /
• pp.30-39
• /
• 1997

Acinetobacter sp. strain JC1 DSM 3803, a carboxydobacterium, was found to grow methylotrophically at the expense of methanol and methlamine, but not of methane, formaldehyde, formate, dimethylamine, or trimethylamine, as the sole source of carbon and energy. The doubling times of the bacterium growing on methanol (0.5%, v/v) and methylamine (0.5%, w/v) at 3$0^{\circ}C$ and pH 6.8 were 4.8 h and 5.7 h, respectively. Cells grown on methanol, however, failed to show typical methanol dehydrogenase and oxidase activities. The cell was found to contain no c-type cytochromes. Cells grown on methanol exhibited higher catalase activity than those grown on pyruvate or glucose. The catalase present in the cells also exhibited peroxidase activity. The catalase activity, growth on methanol of the cell, and oxygen consumption by methanol-grown maldehyde dehydrogenase, formaldehyde reductase, glucose-6-phosphate dehydrogenase, and 6-phosphogluconate dehydrogenase activities were detected from cells grown on methanol.

• Progress in Superconductivity and Cryogenics
• /
• v.22 no.4
• /
• pp.20-23
• /
• 2020

Among many variables in processing the high performance MgB2 bulk superconductors, simple and important approach is to optimize the size dependence of the Mg & B raw powders. The present study is dedicated towards the variation in superconducting properties of MgB2 depending upon the various combination of Mg & B powders with the two different particle sizes respectively. From morphological investigation of the MgB2 samples, narrow and long pores are observed when the larger Mg powders are used, whereas it is rather like the oval shapes with the smaller Mg powders. Also, it can be seen that the connectivity of the MgB2 samples is much enhanced with the smaller size of the B powders. Jc-H properties of the MgB2 samples also indicate that the highest Jc can be obtained when using the smaller size of the B powder with the combination of the smaller Mg powders than that of the larger Mg powders. If the cases with the larger B powers, it is more favorable to select the larger Mg powders with the better Jc-H properties considering shorter diffusion length of Mg and more homogeneous mixture between the Mg & B powders.

• International Journal of Computer Science & Network Security
• /
• v.22 no.5
• /
• pp.143-148
• /
• 2022

Brain tumor classification is an important process that allows doctors to plan treatment for patients based on the stages of the tumor. To improve classification performance, various CNN-based architectures are used for brain tumor classification. Existing methods for brain tumor segmentation suffer from overfitting and poor efficiency when dealing with large datasets. The enhanced CNN architecture proposed in this study is based on U-Net for brain tumor segmentation, RefineNet for pattern analysis, and SegNet architecture for brain tumor classification. The brain tumor benchmark dataset was used to evaluate the enhanced CNN model's efficiency. Based on the local and context information of the MRI image, the U-Net provides good segmentation. SegNet selects the most important features for classification while also reducing the trainable parameters. In the classification of brain tumors, the enhanced CNN method outperforms the existing methods. The enhanced CNN model has an accuracy of 96.85 percent, while the existing CNN with transfer learning has an accuracy of 94.82 percent.

• The Korean Journal of Pesticide Science
• /
• v.12 no.1
• /
• pp.88-96
• /
• 2008

To obtain protoplasts of Colletotrichum acutatum JC24, conidia were inoculated onto cellophane membrane placed on PDA and incubated at $25^{\circ}C$ for 20 hrs under the dark condition. Cellophane membranes, where mycelia were incubated, were soaked into 2% lysing enzyme solution prepared with 0.02 M phosphate buffer (pH 7.0) including 1.2 M sorbitiol. After treatment in 2% enzyme solution for 2 - 3 hrs, it could be possible to harvest $2-3\;{\times}\;10^6$ protoplasts/mL. The effect of several fungicides on reversion ratio was determined by using the protoplasts obtained from C. acutatum JC24. Any protoplasts could not be reversed to mycelia on reversion PDA amended with $10\;{\mu}\;g\;mL^{-1}$ of propineb. With tebuconazole, inhibition ratio of protoplast reversion was 100 and 0.9% at 0.5 and $0.1\;{\mu}\;g\;mL^{-1}$, respectively, while inhibitory effect on mycelial growth was 85.1 and 75.7%. The inhibitory tendency of carbendazim on protoplast reversion was as same as mycelial growth. In the case of strobilurins, trifloxystrobin and kresoxim-methyl, they only could inhibit protoplast reversion of C. acutatum JC24, when salicylhydroxamic acid (SHAM) was amended into reversion PDA with strobilurins.

• Journal of Bio-Environment Control
• /
• v.9 no.1
• /
• pp.47-59
• /
• 2000

In order to investigate the physical and chemical properties of artificial culture media, the specimens were substituted with 5~20％ clay, 10~30％(w) quick lime, 5~l5％(w) burnt plaster and 10％(w) sawdust. Fly ash-clay bodies were sintered at 1,050~1,20$0^{\circ}C$ and then their properties were determined. It was found that 90FA10JC(fly ash ＋clay(90：10, ％(w)) specimen sintered at 1,15$0^{\circ}C$ for 10 min. had good physical and chemical properties. When this composition was supplement with 10％(w) sawdust, bulk density water absorption, apparent porosity, compressive strength and pH after 240 hrs curing time were 1.14, 54.4％, 39.5％, 54 kgf.cm$^{-2}$ and 7.1 respectively. The physical properties of fly ash-quick lime-burnt plaster system specimens were superior to FAJC systems. However, this composition we not suitable as a artificial culture media because of its high pH. In this study, it was shown that 90FA10JC10SD(90FA10JC ＋10％(w) sawdust) system exhibited the best physical properties.

• Journal of Digital Convergence
• /
• v.15 no.7
• /
• pp.239-246
• /
• 2017

We study convergent influence on Job Satisfaction(JS) and its association with Self Efficacy(SE), Job Characteristics(JC) and Occupational Stress(OS) among Hospital Administrative Staff(HAS). The survey was administered to 221 staff from 11 general hospitals located in Jeonbuk area from Nov. 1st, 2016 to Jan. 31st, 2017. The structured self-administered questionaries were used. JS was positively correlated with SE and three sub-domains of JC, and it was negatively correlated with seven sub-domains of OS. With the analysis of covariance structure, OS was more influential on JS than SE and JC. The study found the higher SE and JC, and the lower OC tend to increase JS. The results indicate that the efforts, to increase SE and JC, and to decrease OS, are required to increase the JS of HAS. The results are expected to be useful for organization personnel management to increase the JS of HAS. In the following study, the analysis about convergent additional factors of influence on JS will be needed.