• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.331-332
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• 2007

In this work, the TiO2 pigment influence in HDPE dielectric strength was analyzed. Chemical and structural characterizations were made to identify changes during the processing and your influence in the electrical properties, formulations containing 0, 0.5, 1, 2.5, 4 and 6 of titanium dioxide were processed by extrusion and injection molding with stabilization-antioxidants, ultraviolet stabilizers and plasticizers. The electrical strength tests were analyzed by the statistical distribution of Weibull, and the maximum likelihood method. The high concentrations present lower values to electrical strength. The parameter could be using to insulator panicles dispersion. The TiO2 concentration variation shows that these incorporations implicate strength values increase has a maximum (5,35MV/cm). High pigment concentration induces a little falls in property values. Observing the parameter, minimum experiment electric field (Ebmin) and electric strength value, found that the best electric perform formulation was the formulation with 2.5% TiO2 weight.

• Journal of IKEEE
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• v.27 no.4
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• pp.630-635
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• 2023

SiC is replacing the position of silicon in the power semiconductor field due to its superior resistance to adverse conditions such as high temperature and high voltage compared to silicon, which occupies the majority of existing industrial fields. In this paper, the gate of 4H-SiC Planar MOSFET, one of the power semiconductor devices, was formed with aluminium to make the contrast and parameter values consistent with polycrystalline Si gate, and the threshold voltage, breakdown voltage, and IV characteristics were studied by varying the channel doping concentration of SiC MOSFET.

• Journal of the Korean Vacuum Society
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• v.17 no.2
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• pp.160-164
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• 2008

The Characterization of $MgB_2$ Thin Film by Slow Positron Annihilation Spectroscopy Enhance signal-to-noise ratio, slow positron coincidence Doppler Broadening method has been applied to study of characteristics of $MgB_2$ superconductor film, which were performed at 30 K and 50 K sample temperature near Tc of it. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. The S-parameter values were increased then decreased while the positron implantation energies were increasing, that indicated the diffusion into the samples. The S-parameters of the anisotropic 1 ${\mu}m$ $MgB_2$ thin film which were implanted by positrons at 10 keV are 0.567 at 30 K and 0.570 at 50 K. It is believed that the positrons annihilate with normal-electrons instead of super-electrons in the $MgB_2$ superconductor.

• Korean Journal of Environment and Ecology
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• v.21 no.1
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• pp.22-29
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• 2007

Investigation of carabid beetles as on ecological indicator species for wetland characterization and monitoring was conducted in three types of wetlands such as emergent wetland, forested wetland, and estuary, During the investigation period, twenty-eight species belonging to twenty-two genera and three families(Carabidae, Harpalidae, Brachinidae) were identified. The diversity of carabid beetles at riverine wetland such as Woopo (H'=1.18) and Hwapo-neup (H'=1.08) were higher than in the forested wetland (H'=1.03) and estuarine (H'=0.91). Species compositions in each wetland were significantly different(${\chi}^2=1716.8$, P<0.01). Riverine wetlands differed significantly from the forested wetland. Indicator species for the wetland chose with indicator species analysis were reacted sensitively on the parameter such as soil composition, moisture of soil, and environmental change. Thus, it was consequently suggested that these indicator species may be applied for wetland characterization and monitoring of the wetland ecosystem.

• Journal of the Korean Electrochemical Society
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• v.8 no.3
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• pp.130-134
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• 2005

To the best knowledge, the formation and characterization of InSb nanowires have not been reported yet in spite of its good characteristics as a III-V compound semiconductor. The nanowire arrays were potentiostatically electrodeposited in a mixing solution of indium chloride, antimony chloride, citric acid, and potassium citrate according to our previous work on the electrodeposition of the stoichiometric InSb films. The electrical properties of nanowire arrays were measured by semiconductor parameter analyzer, and the microstructural analysis of the nanowires was conducted by employing XRD. Our experimental results indicate that the InSb nanowires have a highly preferred orientation of (220) direction and also exhibit electrical characteristics of n-type semiconductors which we, however, similar to semi-metals mainly due to their narrow band-gap and high electron mobility.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.41 no.5
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• pp.65-70
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• 2004

In this paper, we present a new methodology to analyze the characteristic of artery by using 4 channels photoplethysmograpy. The proposed parameter is a time difference of pulse transit time(PTT) between Pulse waves at finger site and at toe site. To verify the usefulness of the developed system volume pulse waves on 4 sites were measured simultaneously for total 51 normal subjects (male 26 and female 25) aged from 9 to 83 years old. And then correlations between the analysis parameters and age were evaluated by using linear regression analysis method. As the result of experiments, the change of parameter was found according to ages. The result of regression analysis about relationships between the parameter and ages for n=51, the coefficient of correlation of non-normalized data has 0.79770 in left side and 0.80599 in right side and the coefficient of correlation of normalized data by height has 0.81345 in left side and 0.81605 in right side.

• Journal of the Korean Vacuum Society
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• v.18 no.6
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• pp.447-452
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• 2009

Enhance signal-to-noise ratio, Coincidence Doppler Broadening positron method has been applied to study of characteristics of BaSrFBr:Eu film sample. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. The films were exposed by 0, 3, 5, and 7.5 MeV proton beams ranging from 0 to $10^{13}$ ptls. The S-parameter values were increased as increasing the exposed time and the energies, that indicated the defects generate more.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.4
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• pp.169-174
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• 2011

Nanoscale-biodegradable behaviors of synthesized biphasic calcium phosphates (BCP) powders were characterized using X-ray diffraction (XRD), lattice parameter, and field emission microscopy (FE-SEM). The calcined BCP powders in vitro tested in Hank's balanced salt solution (pH = 7.4, $36.5^{\circ}C$) for 3 weeks. The calculated unit cell parameters for BCP have shown lattice distortion and expansion as irregular changes in the a and c-axis after in vitro.

• Journal of the Korean Vacuum Society
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• v.19 no.6
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• pp.489-494
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• 2010

Enhance signal-to-noise ratio, slow positron coincidence Doppler Broadening method has been applied to study of characteristics of $Nb_3Ge$ superconductor film, which were performed from 20 K to 300 K sample temperature near Tc of it. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. The S-parameter values between 0.598 and 0.594 were decreased while the temperature were decreasing, that indicated the voids into the samples. The temperature dependence came from specific positron trapping rate into the vacancy-type defects. It is believed that the positrons annihilate with normal-electrons instead of super-electrons in the Nb3Ge superconductor.

• Journal of applied mathematics & informatics
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• v.25 no.1_2
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• pp.541-550
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• 2007

This paper presents characterizations of the power distribution with the parameter $\beta=1$ by the independence of the lower record values. We prove $X\;{\in}\;POW({\alpha},\;1)$ for ${\alpha}\;>\;0$, if and only if $\frac{X_{L(n)}}{X_{L(m)}}$ and $X_{L(m)}$ for $1\;{\leq}\;m\;<\;n$ are independent. And we prove that $X\;{\in}\;POW({\alpha},\;1)$ for ${\alpha}\;>\;0$, if and only if $\frac{X_{L(m)}-X_{L(m+1)}}{X_{L(m)}}$ and $X_{L(m)$ for $m\;{\geq}\;1$ are independent or $\frac{X_{L(m)}-X_{L(m+1)}}{X_{L(m+1)}}$ and $X_{L(m)}$ for $m\;{\geq}\;1$ are independent.