• Korean Journal of Materials Research
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• v.11 no.1
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• pp.44-47
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• 2001

Effects of $Er_2O_3$ addition on the dielectric properties of non-reducible $BaTi_3$-based X7R dielectrics with Ni electrode have been studied in reducing atmosphere. X7R with moderate temperature-dependence was developed after addition of $Er_2O_3$ with $MnO_2-MgO$; room-temperature dielectric constant and dissipation factor were >2900 and < 1.0%, respectively. The addition of $Er_2O_3$ greater than 3.0 mol% improved the temperature dependence of dielectric properties, but a significant decrease of the dielectric constant at room-temperature was observed. The TCC curves rebated clockwise with increasing MnO$_2$ content at a given additive system, 1.5 mol% $Er_2O_3$ and 2.0 mol% MgO.

• Journal of the Korean Ceramic Society
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• v.18 no.2
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• pp.119-125
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• 1981

The thermostable resistor was made by using P.T.C.R-N.T.C.R. ceramics. In this study $BaTiO_3$ type P.T.C.R. ceramics and $SnO_2-Sb_2O_3$ type N.T.C.R. ceramics were cocrystallized in one body and electrical resistance was stable under the temperature variation between $25^{\circ}C$-40$0^{\circ}C$. The ceramics showed the most stable electrical resistance for the mal variation when the composition was 0.6P.T.C.R. $BaTiO_3$,$ 0.4SnO_2$ and 0.01 $Sb_2O_3$.

• Journal of Sensor Science and Technology
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• v.28 no.4
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• pp.225-230
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• 2019

$Au@TiO_2$ core-shell decorated rGO nanocomposite (NC) was prepared using a simple solvothermal method followed by heat treatment for gas sensor application. The crystal structure and morphology of the composites were characterized by X-ray powder diffraction and transmission electron microscopy, respectively. The $NO_2$ sensing response of the $Au@TiO_2/rGO$ NC was tested at operating temperatures from $250^{\circ}C$ to $500^{\circ}C$, and was compared with those of the bare rGO and $Au@TiO_2$ core-shell NPs. The $Au@TiO_2/rGO$ NC-based sensor showed a far higher response than the rGO or $Au@TiO_2$ core-shell based sensors, with the maximum response detected when the operating temperature was $400^{\circ}C$. This improved response was due to the high rGO gas absorption capability for $NO_2$ gas and the catalytic effect of $Au@TiO_2$ core-shell NPs in oxidizing $NO_2$ to $NO_3$.

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.253.2-253.2
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• 2008

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.6
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• pp.345-365
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• 2002

In diesem Aufsatz wired versucht, eine Mikrostruktur $f\"{u}r$ ein elektronisehes Detusch-Koreanisehes $W\"{o}rterbueh$ zu entwerfen. Bei gedruekten $W\"{o}rterb\"{u}ehern$ sind die lexikographischen Daten und die $W\"{o}rterbuch­strukturen$ mehr oder weniger standardisiert, dagegen bei elektronischen $W\"{o}rterb\"{u}ehern$ strikt formalisiert. Im Laufe der letzten 50 Jahre sind zwar viele gedruekte, jedoch kaum auf Elektronik basierte zweisprachige $W\"{o}rterb\"{u}cher\;f\"{u}r$ Deutseh-Koreanisch ersehienen. Elektronische $W\"{o}rterb\"{u}cher$ haben mehre Vorteile und sind in diesem Informationszeitalter als Hilfsmittel $f\"{u}r$ den Fremdspraeherwerb unabdingbar. Die Festlegung der logischen Struktur des $W\"{o}rterbuehs\;ist\;f\"{u}r\;die\;W\"{o}rterbucharbeit\;unerl\"{a}{\ss}lich$ und $f\"{u}r$ die Herstellung elektronischer $W\"{o}rterb\"{u}cher$ von Bedeutung, wird jedoch in der koreanischen Praxis oft $vemachl\"{a}{\ss}igt$. Daher weisen die meisten koranischen $W\"{o}rterb\"{u}cher$ keine konsistente Form in der Struktur von $W\"{o}rterbuehdefinitionen$ auf. Aus diesen $Gr\"{u}nden$ schlage ich eine formale logisehe Struktur $f\"{u}r$ ein elektronisches Deutsch-Koreanisches $W\"{o}rterbuch$ vor. $Zun\"{a}chst$ werden grundlegende lexikalische Begriffe $eingef\"{u}hrt,\;anschlie{\ss}end$ wird auf die Analyse der lexikalischen $Eintr\"{a}ge\;f\"{u}r$ ein Deutsch-Koreanisches $W\"{o}rterbuch$ eingegangen. In diesem Beitrag wird keine fertige Miktostruktur $pr\"{a}sentiert$, sondern eine Anregung zur weiteren Diskussion zu einer Mikrostruktur gegeben. Als logisehe Struktur $f\"{u}r$ das elektronische Deutsch-Koreanische $W\"{o}rterbuch$ wird eine glattalphabetische Makrostruktur aufgenommen, die Mikrostruktur als semiintegriert. Die lexikographische Arbeit ist $zeitaufw\"{a}ndig$ und braucht viele $Fachkr\"{a}fte$. Deshalb ist die Festlegung einer konsistenten und objektiven Mikrostruktur eine Voraussetzung der $W\"{o}rterbuchherstellung$. Sie regt auch dazu an, die lexikalischen Informationen im Artikel genauer zu analysieren. Erst dadurch wird ein effektives elektronisches $W\"{o}rterbuch\;m\"{o}glich$, das eine Weiterbenutzung der klassifizierten Informationen $unterst\"{u}tzt$.

• Korean Journal of Materials Research
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• v.14 no.11
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• pp.821-827
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• 2004

Titanium oxide thin films were prepared on Si(100) substrates by R.F. magnetron reactive sputtering at $30\sim200watt$ R.F power range, and annealed at $600^{\circ}C\sim800^{\circ}C$ for 1 hour. The properties of $TiO_2$ thin films were analyzed using x-ray, ${\alpha}-step$, ellipsometer, scanning electron microscopy, and FT-IR spectrometer. Upon in-situ depositions, the initial phase of $TiO_2$ thin film showed non-crystalline phase at R.F. power $30\sim100$ watt. The crosssection of $TiO_2$ thin films were sbserved to be the columnar structure. With the increasing R.F power and annealing temperature, the grain size, crystallinity, refractive index, and void size of titanium oxides showed a tended to increase. The FT-IR transmittance spectra of titanium oxide thin films have the obsorption band of Ti-O bond, Si-O bond, Si-O-Ti bond and O-H bond. With the increase of R.F. power and annealing temperature, these films have the stronger bond structures. It is considered that such a phenomena is due to phase transition and good crystallinity

• Journal of Nutrition and Health
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• v.24 no.4
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• pp.308-313
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• 1991

This study attempted to measure subcutaneous fat thickness by the use of ultrasonic wave in age and sex matched Korean subjects, and to observe correlation between fat thick-ness and physical indices. In male, fat thickness of suprailiac area showed the highest value of $9.40{\sim}9.51mm$ and then subscapular was $6.60{\sim}6.84mm$, femoral was $6.48{\sim}7.04mm$ and triceps regions was $3.48{\sim}3.69mm$. In female, femoral subcutaneous fat thickness was the higher. $11.85{\sim}12.15mm$and then suprailiac was $8.79{\sim}9.87mm$ subscapular was $6.20{\sim}6.91mm$ and triceps fat thickness was $4.80{\sim}4.93mm$. In male, fat thickness of triceps and relative body weight(RBW). body mass index(BMI), triceps or $R\ddot{o}hrer$ index were positively correlated. Correlations between suprailiac and weight, relative body weight(RBW). body mass index(BMT), $R\ddot{o}hrer$ index or subscapular were positively significant. In female. there were positive correlations between fat thickness of femoral and RBW, BMI, or $R\ddot{o}hrer$ index. And there were no positive correlations in other parts of the body.

• Journal of the Korean Society for information Management
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• v.6 no.1
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• pp.15-36
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• 1989

The r a p i d i n c r e a s e o f microcomputer technology has r e s u l t e d i n t h e broad a p p l i c a t i o n t o various f i e l d s . The purpose of t h l s paper 1s to design a computerized r e t r i e v a l system f o r nuclear information m a t e r i a l s using a microcomputer.

• Journal of the Korean Ceramic Society
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• v.37 no.4
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• pp.359-367
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• 2000

Particulate composites of Al2O3/SiC, Al2O3/ZrO2 and Al2O3/ZrO2/SiC have been fabricated to investigate their R-curve behaviors and toughening mechanisms. Al2O3 containing 30 vol% SiC particles of 3${\mu}{\textrm}{m}$ showed rising R-curve behavior owing to the strong crack bridging by SiC particles. The fracture toughness reached 9.1 MPa {{{{ SQRT {m} }} at the crack length of 1000${\mu}{\textrm}{m}$. On the other hand, ZrO2-toughened Al2O3 had a high flat R-curve since it rose steeply in the short crack region due to the well known transformation toughening. For Al2O3/ZrO2/SiC composites, the R-curve behavior was similar to that of Al2O3/SiC but with slightly higher toughness. The SiC particles in this composite decreased the amount of transformable tetragonal phase to reduce the effect of transformation toughening by 50%. It was also found that the fracture toughness of this composite with two different toughening mechanisms was markedly lower than that estimated by the simple addition of two contributions.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.4
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• pp.45-49
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• 2014

In this study, we grew non-polar ZnO nanostructure on (1-102) R-plane sapphire substrates. As for growth method of ZnO, we used hydrothermal synthesis which is known to have the advantages of low cost and easy process. For growth of non-polar, the deposited AZO seed buffer layer with of 80 nm on R-plane sapphire by radio frequency magnetron sputter was annealed by RTA(rapid thermal annealing) in the argon atmosphere. After that, we grew ZnO nanostructure on AZO seed layer by the added hexamethylenetramine (HMT) solution and sodium citrate at $90^{\circ}C$. With two types of additives into solution, we investigated the structures and shapes of ZnO nanorods. Also, we investigate the possibility of formation of 2D non-polar ZnO layer by changing the ratio of two additives. As a result, we could get the non-polar A-plane ZnO layer with well optimized additives' concentrations.