• Bulletin of the Korean Chemical Society
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• 제24권5호
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• pp.566-568
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• 2003

The phosphor $CaTiO_3:Pr^{3+}$ attracts much attention as a low-voltage red phosphor because of its good chromaticity and intrinsic conductivity. The addition of Ga into this CaTiO₃:Pr led the luminance intensity to greatly enhance without the change of the wavelength for the electronic transition and the peak shape of it. The increase of the recombination rate of electron-hole pairs through the Ga ion doping, which was expected to play a role of a hole-trap center, is proposed to be one of the reasons for the enhancement of the cathodoluminescence intensity.

• 대한한의학방제학회지
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• 제20권2호
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• pp.13-28
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• 2012

Objectives : The present study aimed to investigate the pharmacological activity of water and ethanol (EtOH) extracts from Socheongnyong-tang (SCNT) on inflammation and its related disease. Methods : The cells were treated with nontoxic concentrations of water and EtOH extract from SCNT in BEAS-2B, HaCaT, RAW 264.7 and 3T3-L1 cells. These cells were stimulated by tumor necrosis facter (TNF)-${\alpha}$, TNF-${\alpha}$/interferon (IFN)-${\gamma}$, and lipopolysaccharide (LPS), respectively. 3T3-L1 cells were differentiated by insulin. After incubation, supernatant were collected and biological indicator measured by enzyme-linked immunosorbent assay. Results : Our results indicate that the water and EtOH extract of SCNT significantly inhibited the production of regulated on activation normal T-cell expression and secreted (RANTES) by treatment of TNF-${\alpha}$ in BEAS-2B cell, and significantly reduced the production of RANTES and macrophage-derived chemokine increased by treatment of TNF-${\alpha}$/IFN-${\gamma}$ in HaCaT cell. Moreover, those extracts significantly decreased the activity of nitric oxide and prostaglandin $E_2$ in LPS-induced RAW 264.7, and significantly inhibited the increased activity of glycerol-3-phosphate dehydrogenase and expression of leptin induced by differentiation in 3T3-L1 cell. Conclusions : These results indicate that both water and EtOH extract of SCNT has powerful effects on inflammation and its related disease. Therefore, SCNT can be developed as a potential pharmacological agent related various diseases. Although the significant effects were observed in both SCNT water and EtOH extract, the EtOH extract was more effective on most experiments than its water extract. Taken together, these findings indicate that the SCNT EtOH extract may have more potential pharmacological agent.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 춘계학술발표회
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• pp.889-890
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• 2005

• ETRI Journal
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• 제26권2호
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• pp.181-184
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• 2004

For communication between heterogeneous conference systems, it is important to build a conference control protocol independent from signaling protocols. We simulate an XML-based conference control that is under consideration as a standard mechanism. We describe the framework and operations for easy implementation in heterogeneous conference systems. The simulation results show that the proposed control protocol provides a consistent service for an increasing number of conferences and participants in small to mid-size centralized conferencing.

• ETRI Journal
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• 제25권6호
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• pp.510-516
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• 2003

In this paper, we describe the development of a platform-based SoC of a 32-bit smart card. The smart card uses a 32-bit microprocessor for high performance and two cryptographic processors for high security. It supports both contact and contactless interfaces, which comply with ISO/IEC 7816 and 14496 Type B. It has a Java Card OS to support multiple applications. We modeled smart card readers with a foreign language interface for efficient verification of the smart card SoC. The SoC was implemented using 0.25 ${\mu}m$ technology. To reduce the power consumption of the smart card SoC, we applied power optimization techniques, including clock gating. Experimental results show that the power consumption of the RSA and ECC cryptographic processors can be reduced by 32% and 62%, respectively, without increasing the area.

• ETRI Journal
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• 제27권3호
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• pp.304-311
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• 2005

We report on the fabrication of an AlGaAs/InGaAs/GaAs pseudomorphic high electron mobility transistor (PHEMT) using a dielectric-defined process. This process was utilized to fabricate $0.12\;{\mu}m\;{\times}\;100 {\mu}m$ T-gate PHEMTs. A two-step etch process was performed to define the gate footprint in the $SiN_x$. The $SiN_x$ was etched either by dry etching alone or using a combination of wet and dry etching. The gate recessing was done in three steps: a wet etching for removal of the damaged surface layer, a dry etching for the narrow recess, and wet etching. A structure for the top of the T-gate consisting of a wide head part and a narrow lower layer part has been employed, taking advantage of the large cross-sectional area of the gate and its mechanically stable structure. From s-parameter data of up to 50 GHz, an extrapolated cut-off frequency of as high as 104 GHz was obtained. When comparing sample C (combination of wet and dry etching for the $SiN_x$) with sample A (dry etching for the $SiN_x$), we observed an 62.5% increase of the cut-off frequency. This is believed to be due to considerable decreases of the gate-source and gate-drain capacitances. This improvement in RF performance can be understood in terms of the decrease in parasitic capacitances, which is due to the use of the dielectric and the gate recess etching method.

• ETRI Journal
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• 제24권4호
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• pp.290-298
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• 2002

We present, for the first time, a prototype active-matrix field emission display (AMFED) in which an amorphous silicon thin-film transistor (a-Si TFT) and a molybdenum-tip field emitter array (Mo-tip FEA) were monolithically integrated on a glass substrate for a novel active-matrix cathode (AMC) plate. The fabricated AMFED showed good display images with a low-voltage scan and data signals irrespective of a high voltage for field emissions. We introduced a light shield layer of metal into our AMC to reduce the photo leakage and back channel currents of the a-Si TFT. We designed the light shield to act as a focusing grid to focus emitted electron beams from the AMC onto the corresponding anode pixel. The thin film depositions in the a-Si TFTs were performed at a high temperature of above 360°C to guarantee the vacuum packaging of the AMC and anode plates. We also developed a novel wet etching process for $n^+-doped$ a-Si etching with high etch selectivity to intrinsic a-Si and used it in the fabrication of an inverted stagger TFT with a very thin active layer. The developed a-Si TFTs performed well enough to be used as control devices for AMCs. The gate bias of the a-Si TFTs well controlled the field emission currents of the AMC plates. The AMFED with these AMC plates showed low-voltage matrix addressing, good stability and reliability of field emission, and good light emissions from the anode plate with phosphors.

• 한국진공학회지
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• 제14권4호
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• pp.195-200
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• 2005

For the longevity of OLEDs, passivation of OLEDs is an important process step since organic materials used in OLEDs are very vulnerable to moisture. In this work, the passivation effect of the plasma polymerized para-xylene (PP$\rho$X) layers was studied. The PPpX layers deposited by PECVD were formed on top of the cathode with various plasma powers of 50 - 90 W. Passivation effect of PP$\rho$X was significantly dependent upon the deposition plasma power of the PP$\rho$X film. The lifetime of OLEDs with the 70 W deposited PP$\rho$X passivation layer was about 5 times longer than that of the control device.

• Bulletin of the Korean Chemical Society
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• 제28권3호
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• pp.391-396
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• 2007

The three-dimensional structure of an inorganic crystal, CaMoO4 (space group I 41/a, a = 5.198(69) A and c = 11.458(41) A), was determined by electron crystallography utilizing a high voltage electron microscope. An initial structure of CaMoO4 was determined with 3-D electron diffraction patterns. This structure was refined by crystallographic image processing of high resolution TEM images. X-ray crystallography of the same material was performed to evaluate the accuracy of the TEM structure determination. The cell parameters of CaMoO4 determined by electron crystallography coincide with the X-ray crystallography result to within 0.033-0.040 A, while the atomic coordinates were determined to within 0.072 A.

• 대한조선학회논문집
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• 제48권3호
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• pp.215-221
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• 2011

To improve the naval ship acquisition process, systems engineering, modeling and simulation, etc. have been introduced, and there has been ongoing research on acquisition systems for effective support of it. However, due to characteristics of the naval ship acquisition process, development process mainly carried out at a shipyard such as basic design, detailed design, construction and test is difficult to integrate with the acquisition systems of IPT(Integrated Project Team). In addition, research aimed to improve this is rather lacking. In this paper, the naval ship product structure concept proposed in previous research was applied to the basic design system at shipyard, and basic research for expanding the coverage of naval ship acquisition systems to the basic design phase is performed. A data structure of modeling system appropriate to the basic design phase was proposed through research findings and the prototype system based on it was implemented.