• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2007.11a
• /
• pp.36-36
• /
• 2007

$R_2O_3$(R=Bi, B)-RO(R=Ba, Zn)를 주성분으로 하는 Pb-free유리프리트에 높은 굴절률을 가지고 있는 $TiO_2$ filler를 첨가하여 PDP용 백색유전체를 제조하였다. $TiO_2$ type, 함량에 따른 백색유전체로의 반사율 및 유전 특성을 조사하였다. 백색유전체를 소성한 결과 rutile과 anatase를 중량비로 75:25로 혼합하여 $520^{\circ}C$에서 소성한 경우 밀도 및 수축율의 변화를 거의 나타나지 않았다. 그러나 $TiO_2$함량이 15wt.%를 혼합하여 첨가했을 경우 반사율은 높고 접합특성 또한 우수하였다. 또한, 유전상수는 $TiO_2$첨가량이 증가함에 따라 증가하는 경향을 나타내었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1999.11a
• /
• pp.370-373
• /
• 1999

The purpose of this study is to research and develop PAn composite electrode for EDLC. EDLC cell of PAn composite electrode with 1M LiClO$_4$/PC brings out good capacitor performance below 4.0V. The radius of semicircle of PAn composite electrode adding 15wt% SP270 was absolutely small. The total resistance of EDLC cell mainly depended on internal resistance of the electrode. The discharge capacitance of PAn composite with 15wt% SP270 in 1st and 200th cycles was 42 and 42 F/g at current density of 1mA/cm$^2$. The capacitance of PAn composite with 15wt%. SP270 capacitor was larger than that of PAn capacitor without SP270. The coulombic efficiency of EDLC at discharge process of 1 and 200 cycles were 94 and 100% respectively. PAn composite EDLC with 15wt% SP270 content showed good capacitance and stability with cycling.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2000.07a
• /
• pp.691-695
• /
• 2000

This paper present the result of the investigation, the electric properties of insulators due to non-soluble contamination. In general, the humidity and the amount of soluble salts such as NaCl, MgCl$_2$are the most dominant factor. Though the non-soluble do not distribute on conductivity of contaminant layer, that has the hygroscopic property. For this study, we make a mini-fog chamber with transparent acryl and the kaoline was used for non-soluble contaminant. The kaoline was applied with sprayer to get the specific ESDD and NSDD value, then the specimen was dried and installed horizontally. And to measure the leakage current a DAS system was developed with LabView. With the result, we could know the influence of non-soluble content and the relationship between NSDD and ESDD.

• Journal of Sericultural and Entomological Science
• /
• v.41 no.3
• /
• pp.180-184
• /
• 1999

The insecticidal compound priduced by Streptomyces SS-4993 strain was indicated to be a relatively stable small compound by pancreatin treatment. The active compound was adsorbed on HP20 and eluted with 70% acetone. Then, the eluate was extracted with ethyl acetate. The content of the extract was determined by thin layer chromatography (Silica gel 60 F254, hexane-ethyl ether-acetic acid,80 : 20 :1). Three active bands (Rf 0.08, 0.07, 0.88) were identified by dermal application using Bombyx mori larvae. Electrophoretic analysis revealed that the injection of strain SS-4993 culture broth into B. mori larvae induce the reduction of the hemolymph proteins level. Especially, the level of apolipophorin-I was decreased drastically.

• Journal of Welding and Joining
• /
• v.20 no.1
• /
• pp.91-96
• /
• 2002

Three different kinds of substrate used in this study : bare Cu, electroless Ni/Cu substrate with a Nilayer thickness of $5\mu\textrm{m}$, immersion Au/electroless Ni/Cu substrate with the Au and Ni layer of $0.15\mu\textrm{m}$ and $5\mu\textrm{m}$ thickness, respectively. The wettability and interfacial tension between various substrate and Sn-3.5Ag solder were examined as a function of soldering temperature, types of flux. The wettability of Sn-3.5Ag solder increased with soldering temperature and solid content of flux. The wettability of Sn-3.5Ag solder was affected by the substrate metal finish used, i.e., nickel, gold and copper. Intermetallic compound formation between liquid solder and substrate reduced the interfacial energy and decreased wettability.

• Journal of the Mineralogical Society of Korea
• /
• v.3 no.1
• /
• pp.34-43
• /
• 1990

Crystal-chemical study of hexagonal 7$\AA$ phyllomanganate minerals reveals that they have hexagonal layer structures with variable c dimensions which depend on the nature of interlayer cations and content of water molecules between edge-sharing [MnO6] octahedral layers. Approximately one out of nine octahedral sites is statistically vacant, leading to the general unit cell formula R2xMn4+1-xO2.nH2O, where R=Ca, Mn2+, Mg, K, Na;x=0.09-0.14 ; n-0.37-0.84. Z=1. The minerals of this formula fall under the name of rancieite group. It includes Ca-diminant (rancieite), Mn2+-dominant (takanelite), Na-dominant (birnessite), and Mg-dominant members. Minerals of the rancieite group occur predominantly in two different hydration states, i.e., n shows the values around 0.35 and 0.75. It is suggested that minerals of higher hydration state be called as species(i.e., rancieite, etc.) and those of lower hydration state be called as dehydrated varieties(i.e., dehydrated rancieite,etc.).

• Journal of the Korean Society for Heat Treatment
• /
• v.8 no.2
• /
• pp.127-136
• /
• 1995

The simultaneous addition of Al and Cr to the surface of Ni-and Fe-base alloy provides enhanced resistance to oxidation and corrosion in high temperatures. However, because of the large differences in thermodynamic stabilities of the volatile halides of Al and Cr, the codeposition of Al and Cr by halideactivated pack cementation is only possible for very specific, limited combinations of conditions. In this study, the experiments on the combinations of various metallic source powders and activators were conducted in order to obtain codeposition layers of Al and Cr on Ni with adequate composition by pack cementation. When Cr-Al masteralloy was used as a source powder, it was not easy to control Al and Cr content sensitively in the coating layers. On the other hand, when pure Cr and Al powder was used, ${\beta}$-NiAl layer containing about 20wt % Cr was obtained.

• Nuclear Engineering and Technology
• /
• v.51 no.3
• /
• pp.647-653
• /
• 2019

A comprehensive study of photon interaction features has been made for some alloys containing Pd and Ag content to evaluate its possible use as alternative gamma radiations shielding material. The mass attenuation coefficient (${\mu}/{\rho}$) of the present alloys was measured at various photon energies between 81 keV - 1333 keV utilizing HPGe detector. The measured ${\mu}/{\rho}$ values were compared to those of theoretical and computational (MCNPX code) results. The results exhibited that the ${\mu}/{\rho}$ values of the studied alloys are in same line with results of WinXCOM software and MCNPX code results at all energies. Moreover, Pd75/Ag25 alloy sample has the maximum radiation protection efficiency (about 53% at 81 keV) and lowest half value layer, which shows that Pd75/Ag25 has superior gamma radiation shielding performance among the compared other alloys.

• Nuclear Engineering and Technology
• /
• v.51 no.3
• /
• pp.853-859
• /
• 2019

A comprehensive study of photon interaction features has been made for some alloys containing Pd and Ag content to evaluate its possible use as alternative gamma radiations shielding material. The mass attenuation coefficient (${\mu}/{\rho}$) of the present alloys was measured at various photon energies between 81 keV-1333 keV utilizing HPGe detector. The measured ${\mu}/{\rho}$ values were compared to those of theoretical and computational (MCNPX code) results. The results exhibited that the ${\mu}/{\rho}$ values of the studied alloys are in the same line with results of WinXCOM software and MCNPX code results at all energies. Moreover, Pd75/Ag25 alloy sample has the maximum radiation protection efficiency (about 53% at 81 keV) and lowest half value layer, which shows that Pd75/Ag25 has superior gamma radiation shielding performance among the other compared alloys.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2019.06a
• /
• pp.84-85
• /
• 2019

MPEG-NNR (Compression of Neural Network for Multimedia Content Description and Analysis) aims to define a compressed and interoperable representation of trained neural networks. In this paper, we present a low-rank approximation to compress a CNN used for image compression, which is one of MPEG-NNR use cases. In the presented method, the low-rank approximation decomposes one 2D kernel matrix of weights into two 1D kernel matrix values in each convolution layer to reduce the data amount of weights. The evaluation results show that the model size of the original CNN is reduced to half as well as the inference runtime is reduced up to about 30% with negligible loss in PSNR.