• Korean Journal of Materials Research
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• v.9 no.8
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• pp.825-830
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• 1999

Characteristics of SiOF films deposited by a FTES/$O_2$-plasma enhanced chemical vapor deposition method have been investigated using Fourier transform infrared spectroscopy, X-ray photoelectro spectroscopy, and ellipsometry. Electrical properties such as dielectric constant, dielectric breakdown and leakage current density are investigated using C-V and I-V measurements with MIS(Au/SiOF/p-Si) capacitor structure. Stepcoverage of the films have been also characterized using scanning electron microscopy and ellipsometry. A high quality SiOF film was formed on that the flow rates of FTES and $O_2$were 300sccm, respectively. The dielectric constant of the deposited SiOF film was about 3.1. This value is lower than that of the oxide films obtained using other method. The dielectric breakdown field and leakage current are more than 10MV/cm and about $8[\times}10^{9}A/\textrm{cm}^2$, respectively. The deposited SiOF film with thickness as $2500{\AA}$ on the $0.3{\mu}{\textrm}{m}$ metal pattern shows a high step-coverage without a void.

• Fire Science and Engineering
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• v.19 no.1 s.57
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• pp.93-98
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• 2005

The purpose of this paper is to judge the damage cause of instrument transformer(MOF; Metering Out Fit) installed in 22.9kV power receiving system. In the three-dimensional analysis of the restored MOF, the damage pattern progressed from inside to outside, there was no damaged part in the upside. The resistance of the carbonized middle part is roughly $100\kappa\Omega$ and the exothermic temperature at inside is presumed as about $300\~800^{\circ}C$ in the result of metallurgical structure analysis. The structure and the composition rate on metal surface by SEM is similar. In the result of FT-IR analysis, we can observe the absorbtion peak at $1500cm^{-1}\;and\;1730 cm^{-1}$ is small. The high exothermic peak showed at the center part of the coil in the result of DTA.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.2
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• pp.131-140
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• 2000

Heavy metals (Fe, Mn, Cr, Co, Cu, Ni, Zn, Pb) were determined in ninety-one surface sediments collected from Kwangyang Bay, south coast of Korea. The data show that the Fe, Cr, Ni, and Zn distribution in the bay can be described by metal vs. grain size relationship. However, the distribution pattern of Mn, Co, Cu and Pb were found to be changed because they are anthropogenically enriched to sediment. Correlation matrix and R-mode factor analyses revealed that two important factors controlling the distribution of metals in the bay are grain size and anthropogenic input.

• Molecular & Cellular Toxicology
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• v.3 no.2
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• pp.132-136
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• 2007

Zinc is essential metal and plays a role in a wide variety of physiological and biochemical processes. Prostate gland contains high level of zinc, generally 3-10 folds higher than other organs. Prostatic zinc uptake is resulted from the existence of zinc transporter (ZnT) protein families in membrane. In this study, we investigated the difference of zinc uptake efficiency of zinc-aspartate complex (Zn-Asp) into various organs compared with $ZnSO_4$. We observed that Plasma zinc concentration in both $ZnSO_4$ and Zn-Asp administrated group was increased progressively following administration, and reached a peak level at 2 hr. The increasing pattern of zinc concentration was similar to each groups, however the zinc concentration of Zn-Asp administrated group was higher than that of $ZnSO_4$ administrated group. We found that prostatic zinc level of Zn-Asp administrated group was higher than $ZnSO_4$ administrated group, and was increased approximately $\sim$2.7 fold and $\sim$4.2 fold at 4 and 8 hr after administration. From these observations, we suggest than Zn-Asp has high uptake efficiency of zinc into the prostate gland. Therefore, Zn-Asp is potentially useful treatment of many prostatic diseases.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.436-437
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• 2012

Double patterning technology (DPT) has been suggested as a promising candidates of the next generation lithography technology in FLASH and DRAM manufacturing in sub-40nm technology node. DPT enables to overcome the physical limitation of optical lithography, and it is expected to be continued as long as e-beam lithography takes place in manufacturing. Several different processes for DPT are currently available in practice, and they are litho-litho-etch (LLE), litho-etch-litho-etch (LELE), litho-freeze-litho-etch (LFLE), and self-aligned double patterning (SADP) [1]. The self-aligned approach is regarded as more suitable for mass production, but it requires precise control of sidewall space etch profile for the exact definition of hard mask layer. In this paper, we propose etch end point detection (EPD) in spacer etching to precisely control sidewall profile in SADP. Conventional etch EPD notify the end point after or on-set of a layer being etched is removed, but the EPD in spacer etch should land-off exactly after surface removal while the spacer is still remained. Precise control of real-time in-situ EPD may help to control the size of spacer to realize desired pattern geometry. To demonstrate the capability of spacer-etch EPD, we fabricated metal line structure on silicon dioxide layer and spacer deposition layer with silicon nitride. While blanket etch of the spacer layer takes place in inductively coupled plasma-reactive ion etching (ICP-RIE), in-situ monitoring of plasma chemistry is performed using optical emission spectroscopy (OES), and the acquired data is stored in a local computer. Through offline analysis of the acquired OES data with respect to etch gas and by-product chemistry, a representative EPD time traces signal is derived. We found that the SE-EPD is useful for precise control of spacer etching in DPT, and we are continuously developing real-time SE-EPD methodology employing cumulative sum (CUSUM) control chart [2].

• Korean Journal of Materials Research
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• v.22 no.5
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• pp.249-252
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• 2012

Fe doped $TiO_2$ nanoparticles were prepared under high temperature and pressure conditions by mixture of metal nitrate solution and $TiO_2$ sol. Fe doped $TiO_2$ particles were reacted in the temperature range of 170 to $200^{\circ}C$ for 6 h. The microstructure and phase of the synthesized Fe doped $TiO_2$ nanoparticles were studied by SEM (FE-SEM), TEM, and XRD. Thermal properties of the synthesized Fe doped $TiO_2$ nanoparticles were studied by TG-DTA analysis. TEM and X-ray diffraction pattern shows that the synthesized Fe doped $TiO_2$ nanoparticles were crystalline. The average size and distribution of the synthesized Fe doped $TiO_2$ nanoparticles were about 10 nm and narrow, respectively. The average size of the synthesized Fe doped $TiO_2$ nanoparticles increased as the reaction temperature increased. The overall reduction in weight of Fe doped $TiO_2$ nanoparticles was about 16% up to ${\sim}700^{\circ}C$; water of crystallization was dehydrated at $271^{\circ}C$. The transition of Fe doped $TiO_2$ nanoparticle phase from anatase to rutile occurred at almost $561^{\circ}C$. The amount of rutile phase of the synthesized Fe doped $TiO_2$ nanoparticles increased with decreasing Fe concentration. The effects of synthesis parameters, such as the concentration of the starting solution and the reaction temperature, are discussed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.6
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• pp.447-452
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• 2005

This study was performed to investigate the differences among the 44 varieties of Japonica rice by using the electronic nose. The volatile patterns of milled rice and its cooked rice were generated by twelve metal oxide sensors (MOS). The MSO responses were evaluated by principal component analysis and cluster analysis. Milled rice was classified into three groups; Group I included most of varieties, Group II was Daejinbyeo, Chucheongbyeo, and Group III was Mangumbyeo, Nampyeongbyeo, Shindongjinbyeo. But the discrimination of cooked rice was not identified. Also the result of correlation analysis appeared that the volatile of milled rice was not significantly related to that of cooked rice. Electronic nose system was considered as not depend on our study results sufficient to predict the volatile pattern of cooked rice.

• Journal of Sensor Science and Technology
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• v.8 no.6
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• pp.461-468
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• 1999

In this paper, we have implemented a gas recognition system for classification and identification of explosive gases such as methane, propane, and butane using a sensor array and an artificial neural network. Such explosive gases which can be usually detected in the oil factory and LPG pipeline are very dangerous for a human being. We analyzed the characteristics of a multi-dimensional sensor signals obtained from the nine sensors using the principal component analysis(PCA) technique. Also, we implemented a gas pattern recognizer using a multi-layer neural network with error back propagation learning algorithm, which can classify and identify the sorts of gases and concentrations for each gas. The simulation and experimental results show that the proposed gas recognition system is effective to identify the explosive gases. And also, we used DSP board(TMS320C31) to implement the proposed gas recognition system using the neural network for real time processing.

• Economic and Environmental Geology
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• v.36 no.4
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• pp.275-284
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• 2003

We collected the samples of stream sediments from primary channels in order to establish natural background of major and minor elements for geologic units in the Gurye area. Stream sediments samples having no possibility of contamination effect and representing drainage basins composed of uniform geology, were collected from April to May in 1999, the chemical analysis of which was carried out. The tolerable level was used to investigate the enrichment degree of harmful elements. The contents of Ni and Cr exceeded the tolerance level in some sections. The tolerance level excess of those elements was regarded as the effect of the metamorphic rock which constituted the bed rock of the area. In order to identify the comprehensive enrichment pattern, the tolerable level was used in calculating the enrichment index. The enrichment index of harmful heavy metals showed that Granite gneiss area is 0.39, Porphyroblastic granite gneiss area 0.32, Biotite gneiss area 0.42, Migmatitic gneiss area 0.41, Tuff area 0.30, Andesite area 0.46, Conglomerate area 0.42, and Granite area 0.26. Those results showed that natural background of Gurye area had not been exposed to harmful heavy metal elements.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.1
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• pp.94-99
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• 2017

Nowadays, digital dentistry is generally applied to prosthodontics with fabrication of inlays or any other fixed prostheses by utilizing CAD/CAM (computer-aided design/computer-aided manufacturing) technology and intraoral scanner. However, in fabricating removable prosthesis, there are some limitations for digital technology to substitute conventional casting method. Therefore, approaching removable prostheses fabrication with CAD/CAM technology would be a meaningful trial. In this case report, Kennedy class III mandibular edentulous patient who was in need of increasing the vertical dimension of occlusion was treated with removable partial denture using CAD and rapid prototyping technique. Surveying and designing the metal framework of the partial denture was performed with CAD, and sacrificial plastic pattern was fabricated with rapid prototyping technique. During the follow up period of nine months, the removable partial denture has provided satisfactory results in esthetics and function.