• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1988.05a
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• pp.7-9
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• 1988

This paper considers problems which must be overcome to produce long lengths of superconductor wire from the 90K Tc superconducting ceramic material, $Y_1Ba_2Cu_3Ox$. Attention is focused on the powder-in-tube process where the superconducting powder is placed in a tube which is then formed into wire. Two major problems are considered, control of the oxygen level and improvement of Jc in the final wire. The results show that Jc of the wire were $400A/cm^2$ at liquid nitrogen temp.

• Progress in Superconductivity
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• v.10 no.1
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• pp.17-22
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• 2008

We have examined the effect of ball-milling on the superconducting properties of $MgB_2$ doped with C. The ball-milling of pre-reacted $MgB_2$ powder was carried out in dry or wet state using C or diethylenetriamine ($C_{4}H_{13}N_3$) as additives. The diethylenetriamine, whose chemical formula contains no oxygen, was chosen to avoid an excess oxidation during doping. The superconducting transition temperature (Tc) of the ball-milled or doped $MgB_2$ powders was only slightly smaller than that of undoped $MgB_2$. The critical current density (Jc) of the highly ball-milled $MgB_2$ was higher than that of C-doped $MgB_2$. The addition of diethylenetriamine was detrimental to Jc, although Tc was almost unchanged.

• Journal of the Korean institute of surface engineering
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• v.24 no.2
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• pp.67-72
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• 1991

The feasibility of preparing superconducting $Y_1Ba_2Cu_3O_y$ films on metallic substrate was exmined in an attempt to fabricate a tape conductor. Deposition methods employed were sputtering, laser ablation, and plasma flash evaporation. Although zero resistance temperature (Tc) is achieved above 90 K, critical current density values (Jc) obtained so far is still low as compared with those reported in the films grown on single crystal substrates. This may be caused by the misalignment of the crystal structure of the films on metal substrates. A further improvement if Jc for highly-oriented polycrystalling films is being investigated at the present time.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.5
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• pp.464-467
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• 2005

BiSrCaCuO superconducting ceramic thick films were fabricated by chemical process. The x ray diffraction pattern of the BiSrCaCuO thick films contained 110 K phase. The critical temperature of BiSrCaCuO thick films were Tc=95 K-97 K. The critical temperature and critical density of BiSrCaCuO thick film grown at $750 {\circ}C$ were Tc = 95 K and $Jc= 7{\times}10^{6} A/cm^{2}$ We obtained high-Jc as-grown BiSrCaCuO on an MgO substrate by low fressure CVD.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.333.1-333.1
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• 2002

Streptomyces tendae JC412 secreted two forms of protease(ST -1 and ST -2) when grown in OSY medium (oatmeal 1.5%. soybean meal 2%. dried yeast 1 %) supplemented with glucose(0.5%) and KH2PO4(0.05%). Initial pH of the culture medium was adjusted to 10.0 with NaOH and incubated at $27^{\circ}C$ on a rotary shaking incubator (180rpm). High- molecular-weight protease ST-1 was heat labile. whereas low molecular protease ST-2(22.000 Da) was reported to be heat stable. (omitted)

• International Journal of Computer Science & Network Security
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• v.23 no.6
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• pp.99-106
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• 2023

Now a days, large volumes of data is accumulating in every field due to increase in capacity of storage devices. These large volumes of data can be applied with data mining for finding useful patterns which can be used for business growth, improving services, improving health conditions etc. Data from different sources can be combined before applying data mining. The data thus gathered can be misused for identity theft, fake credit/debit card transactions, etc. To overcome this, data mining techniques which provide privacy are required. There are several privacy preserving data mining techniques available in literature like randomization, perturbation, anonymization etc. This paper proposes an Enhanced Hybrid Privacy Preserving Data Mining(EHPPDM) technique. The proposed technique provides more privacy of data than existing techniques while providing better classification accuracy. The experimental results show that classification accuracies have increased using EHPPDM technique.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2001.06a
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• pp.2-5
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• 2001

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.291.2-291
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• 1995

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.260.1-260
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• 2000

No Abstract, See Full Text

• Progress in Superconductivity
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• v.7 no.1
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• pp.87-91
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• 2005

[ $YBa_{2}Cu_{3}O_{7-x}$ ] thin films were fabricated on $LaAlO_3$(100) substrate by TFA-MOD process. Yttrium-excess (0, 2.5, 5, 10, 15, 20 $at\%$) coating solution was prepared by adding extra amount of yttrium into a stoichiometric(Y:Ba:Cu=1:2:3) TFA precursor solution. Results are presented concerning the influence of excess yttrium additions on the microstructure development and superconducting properties of $YBa_{2}Cu_{3}O_{7-x}$ film. Large sized CuO particles was observed by SEM EDS investigation. The addition of excess yttrium affected little on $T_c$ of $YBa_{2}Cu_{3}O_{7-x}$ film. $J_c$ of YBCO film was enhanced with excess yttrium addition. Jc maximum of $2.21\;MA/cm^2$ (77 K, self field) appeared with the $15\;at\%$ addition of excess yttrium. With further yttrium addition up to $20\;at\%$, Jc decreased down to $0.9\;MA/cm^2$.