• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.217-220
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• 2001

The possibility of cerium dioxide $(CeO_2)$ thin films as insulators of metal erroelectric insulator semiconductor (MFIS) structures have been studied. The etching $CeO_2$ thin films have been perfonned in an inductively coupled $Cl_{2}/CF_{4}/Ar$ plasma. The high etch rate of the $CeO_2$ thin film was $250\AA /m$ at a 10 % addition of $Cl_2$ into the $Ar(80)/CF_{4}(20)$. The surface reaction of the etched $CeO_2$ thin films was investigated using X-ray photoelectron spectroscopy (XPS) analysis. There are Ce-Cl and Ce-F bonding by chemical reaction between Cl, F and Ce. These products can be removed by the physical bombardment of incident Ar ions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.217-220
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• 2001

The possibility of cerium dioxide (CeO$_{7}$ ) thin films as insulators of metal erroelectric insulator semiconductor (MFIS) structures have been studied. The etching CeO$_2$ thin films have been performed in an inductively coupled C1$_2$/CF$_4$/Ar plasma. The high etch rate of the CeO$_2$ thin film was 250 ${\AA}$/m at a 10% addition of Cl$_2$ into the Ar(80)/CF$_4$(20). The surface reaction of the etched CeO$_2$ thin films was investigated using X-ray photoelectron spectroscopy (XPS) analysis. There are Ce-Cl and Ce-F bonding by chemical reaction between Cl, F and Ce. These products can be removed by the physical bombardment of incident Ar ions.

• Honam Mathematical Journal
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• v.45 no.3
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• pp.397-409
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• 2023

Let R be an associative ring with identity and M be a left R-module. In this paper, we define modules that have the property (δ-CE) ((δ-CEE)), these are modules that have a δ-supplement (ample δ-supplements) in every cofinite extension which are generalized version of modules that have the properties (CE) and (CEE) introduced in [6] and so a generalization of Zöschinger's modules with the properties (E) and (EE) given in [23]. We investigate various properties of these modules along with examples. In particular we prove these: (1) a module M has the property (δ-CEE) if and only if every submodule of M has the property (δ-CE); (2) direct summands of a module that has the property (δ-CE) also have the property (δ-CE); (3) each factor module of a module that has the property (δ-CE) also has the property (δ-CE) under a special condition; (4) every module with composition series has the property (δ-CE); (5) over a δ-V -ring a module M has the property (δ-CE) if and only if M is cofinitely injective; (6) a ring R is δ-semiperfect if and only if every left R-module has the property (δ-CE).

• Progress in Superconductivity and Cryogenics
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• v.10 no.1
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• pp.1-5
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• 2008

The effect of $BaCeO_3$ doping on the critical current density of YBCO film by TFA-MOD method was studied. $BaCeO_3$ doping was made by two method; one is direct addition of $BaCeO_3$ nano-sized powder prepared by citrate process followed by grinding with planetary ball mill for 10 hours. Another is addition of Ba-Ce precursor solution prepared with Ba-acetate and Ce acetate dissolved in TFA to the YBCO-TFA precursor solution. The film was made by standard dip coating and heat treatment process with conversion temperature of $790^{\circ}C$ in 1000 ppm oxygen containing moisturized Ar gas atmosphere. The direct addition of $BaCeO_3$ powder resulted in YBCO film with good epitaxial growth and no evidence of second phase formation. The addition through precursor solution resulted in the increase of critical current density upto 30 at% doping and uniform dispersion of $BaCeO_3$ fine inclusion was confirmed by SEM-EDX.

• Journal of the Optical Society of Korea
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• v.16 no.1
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• pp.76-79
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• 2012

$Tb_3Al_5O_{12}:Ce$ (TAG:Ce) thin films were successfully deposited by a pulsed laser ablation method on a quartz substrate, and low-temperature post-annealing effects on luminescent properties were investigated in detail. TAG:Ce thin films were analyzed by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy. The as-deposited films were amorphous, and post-annealing above $700^{\circ}C$ was required for crystallization. The post-annealed TAG:Ce thin films showed strong and broad emission bands around 542 nm and excitations at 451 nm, which all corresponded to transitions between the 4f ground level to the $5d^1$ excited levels of Ce ion.

• Journal of the Korean Ceramic Society
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• v.28 no.7
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• pp.541-548
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• 1991

Sinterability and stability of TZP ceramics co-stabilized by 12 mol% CeO2 and divalent or trivalent oxides less than 1 mol% were investigated. Divalent and trivalent oxides increased stability of tetragonal ZrO2. 100% tetragonal ZrO2 phase was obtained by doping 12 mol% CeO2 and 0.2 mol% CaO and MgO respectively when sintering was carried out at 1500$^{\circ}C$ for 2 hours. Divalent and trivalent oxides improved sinterability and inhibit grain growth of ZrO2. And it was found that CaO was the most effective sintering aid and grain growth inhibitor for ZrO2 in this study. Incorporation of divalent and trivalent oxides into 12Ce-TZP increased the strength of 12Ce-TZP and particulary 12Ce, 0.4Ca-TZP exhibited a flexural strength of about twofold greater than 12Ce-TZP.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.4
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• pp.825-830
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• 2009

The purpose of this research was to investigate the effects of Calendula officinalis extract (CE) on the activation of murine lymphocytes and macrophages. CE was administered p.o. once a day for 7 days at the concentration of 500 mg/kg. The administration of CE increased the viability of thymocytes, but decreased the viability of splenocytes. Also, CE increased the viability of thymocytes and splenocytes at the concentration of $5{\mu}g$/ml in vitro. The administration of CE did not affect the population of thymic $CD4^+$/$CD8^+$ cells and splenic $CD4^+$/$CD8^+$ cells. Furthermore, the administration of CE enhanced the phagocytic activity of peritoneal macrophages, but decreased the phagocytic activity in vitro. CE decreased the production of nitric oxide from peritoneal macrophages in vivo and in vitro system. These results suggest that CE enhance of cell viability by a direct influence on thymocytes and phagocytic activity by an indirect influence on peritoneal macrophages.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.10
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• pp.865-870
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• 2003

The MFIS (Metal-Ferroelectric-Insulator-Semiconductor) capacitors were fabricated using a metalorganic decomposition method. Thin layers of CeO$_2$ were deposited as a buffer layer on Si substrate and BLT thin films were used as a ferroelectric layer. The electrical and structural properties of the MFIS structure were investigated. X -ray diffraction was used to determine the phase of the BLT thin films and the quality of the CeO$_2$ layer. The morphology of films and the interface structures of the BLT and the CeO$_2$ layers were investigated by scanning electron microscopy. The width of the memory window in the C-V curves for the MFIS structure is 2.82 V. The experimental results show that the BLT-based MFIS structure is suitable for non-volatile memory FETs with large memory window.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.04a
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• pp.516-517
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• 2013

Whole body vibration is very important for operators in construction equipment (CE) industry. There is ISO 2631 regulation to protect operators of CE. Recently WBV is one of critical performance parameters of CE to give operators much better comfortable working environment. And there are many kinds of numerically simplified human body model for the motor industry. We applied one human body model in ISO 5982 for the CE development at early stage. And we've checked the validity of this model to consider WBV by the operator comfort point of view.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.177-179
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• 2002

본 연구는 Ag와 Ce이 함유된 유리를 용융법에 의해 제조하였으며, 355nm Nd:YAG 펄스 레이저를 조사하였을 때의 광학적 특성과 열처리과정에서 발생하는 결정화의 변화과정에 대해 평가하였다. Ce이 함유된 유리는 환원 분위기에서 제조되었으며, Optical Absorption을 통하여 Ce$^{3+}$ 이온이 존재하는 유리의 흡수대역을 관찰하고자 하였다. Photo Luminescence(PL) 측정을 통해 Ce$^{3+}$ 이 존재하고 있음을 확인하였으며, Ce$^{3+}$ 이온의 5d$\longrightarrow$4f 전이를 관찰하였다. 이와같이 Ce$^{3+}$ 가 함유된 유리는 레이저를 조사하였을 경우 PL의 강도가 저하됨을 확인하였다. 열처리과정에서 발생하는 결정화현상을 고찰하기 위해 열분석을 실시하였으며, 레이저조사된 유리에서 최대결정화온도가 감소함을 관찰하였다.