• 한국자기학회:학술대회 개요집
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• 한국자기학회 2008년도 Asian Magnetics Conference
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• pp.189.2-189.2
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• 2008

• 천문학회보
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• 제36권2호
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• pp.145.1-145.1
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• 2011

We present results of two-color VR photometry of the intermediate polar RXS J1803. The data were aquired using the Korean 1-m telescope located at Mt. Lemmon, USA. Different "high" and "low" luminosity states, similar to other intermediate polars, were discovered. No statistically significant variability of the color index with varying luminosity was detected. The orbital variability was found to be not statistically significant. Spin maxima timings were determined, as well as the photometric ephemeris for the time interval of our observations. The spin period variations, caused by interaction of the accretion structure with the rotating magnetic white dwarf, were also detected. These variations are of complicated character, and their study requires further observations. We determine the color transformation coefficients for our photometric systems, and improve on the secondary photometric standards.

• Journal of Magnetics
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• 제7권3호
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• pp.80-93
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• 2002

The role of magnetic anisotropy of the antiferromagnetic layer on the magnetization process of exchange coupled polycrystalline ferromagnetidantiferromagnetic bilayers is discussed. In order to elucidate the magnetic torque response of Ni-Fe/Mn-Ir bilayers, the single spin ensemble model is newly introduced, taking into account the two-dimensionally random distribution of the magnetic anisotropy axes of the antiferromagnetic grains. The mechanism of the reversible inducement of the exchange anisotropy along desirable directions by field cooling procedure is successfully explained with the new model. Unidirectional anisotropy constant, J$k$, of polycrystalline Ni-Fe/Mn-Ir and Co-Fe/Mn-Ir bilayers is investigated as functions of the chemical composition of both the ferromagnetic layer and the antiferromagnetic layer. The effects of microstructure and surface modification of the antiferromagnetic layer on JK are also discussed. As a notable result, an extra large value of J$k$, which exceeds 0.5 erg/cm$^2$, is obtained for $Co_{70}Fe_{30}Mn_{75}Ir_{25}$ bilayer with the ultra-thin (50${\AA}$∼100${\AA}$) Mn-Ir layer. The exchange anisotropy of $Co_{70}Fe_{30}$ 40 ${\AA}/Mn_{75}Ir_{25}$ 100 ${\AA}$ bilayer is stable for thermal annealing up to $400{^{\circ}C}$, which is sufficiently high for the application of spin valve magnetoresistive devices.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.335-336
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• 2009

저가격 고효율 실리콘 태양전지를 구현하기 위하여 핵심적으로 적용되는 공정인 SOD(Spin on Doping) 확산공정 최적화에 관하여 연구하였다. n-type 도핑 물질로는 인(P509)을 사용하였으며, Spinning 속도와 Spinning 시간을 각 3000 rpm, 30 초로 고정하고 급속 열처리로에서 확산 온도와 확산 시간을 $800\;^{\circ}C\;{\sim}\;950\;^{\circ}C$, 2 분에서 20 분까지 가변하며 확산공정을 실시하였다. 4-Point Probe 장비로 에미터 표면 저항을 측정한 결과 확산 온도 $850\;^{\circ}C$에서 5분간 열처리 하여 확산 공정을 하였을 때 저가의 고효율 실리콘 태양전지를 구현하는데 적용 하기위한 $30\;{\sim}\;50\;{\Omega}$-sq의 에미터 표면 저항을 만족 시키는 $36\;{\Omega}$-sq의 값을 얻을 수 있었다.

• 한국안광학회지
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• 제12권1호
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• pp.17-22
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• 2007

Ti-나프텐산염과 금속을 출발원료로 사용하고, 스핀코팅-열분해법을 이용하여 실리카 유리위에 박막을 제조하였다. 도포된 박막은 $500^{\circ}C$ 공기에서 10min동안 열처리하였다. 이를 5회 코팅한 박막은 마지막으로 공기에서 $600^{\circ}C$에서 30min으로 하였다. 박막의 특성을 분석하기 위하여 X-선 회절 분석, 전자현미경, UV스펙트럼을 이용하여 분석하였다. 밴드갭에서 가장 큰 장파장 쪽으로 이동은 Fe을 도핑한 $TiO_2$ 박막이었다.

• 한국항공우주학회지
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• 제35권1호
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• pp.79-86
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• 2007

회전 발사체용 마그너스 효과 풍동실험 측정장치를 개발하였다. 국방과학연구소 풍동실험실에서는 고속풍동실험에 앞서 지상기능시험과 마그너스 저속풍동실험을 수행하였으며 마그너스 모형은 분당 약 6,000~10,000 회전하였으며, 속도 100 m/sec에서 측정한 마그너스 효과는 무차원 회전특성인자에 대해 선형적인 변화특성을 보였다. 동일형상 모형에 대해 미국 AEDC-4T 풍동에서 기 수행하였던 마그너스 측정결과와의 비교검토를 수행하였다.

• 센서학회지
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• 제26권5호
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• pp.366-369
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• 2017

This work presents a detailed study of several parameters on the spray coating method for fabricating a flexible cantilever. Conventionally, spin coating method have been widely used in the microelectromechanical system (MEMS) fabrication process. However, the major drawback of this method is the difficulties in protecting various topography with photoresist film, particularly when the device is manufactured in high aspect ratio. It is also a challenging process to form a small pattern in the etched area. On the other hand, the commercial spray coating systems are not advantageous from an economic perspective and the technique is also providing less efficient. In order to solve these issues, we have developed a manual spray coating system which can be efficiently used by combining the accessories available in the laboratory. The developed spray coating system consists of a spin-coater, motorized stage, a spray gun with the capable of controlling centrifugal force, injection amount, injection angle, and spray range. The major advantage of the proposed spray coating system is its reasonable fabrication cost. Secondly, the system can be easily disassembled after finishing the coating experiment. Owing to the mentioned advantages, we sincerely believe that the proposed spray coating system can be effectively used in many related applications.

• 한국자기학회지
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• 제20권6호
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• pp.212-215
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• 2010

비정질 Ga 박막은 벌크에 비해 높은 초전도 임계온도와 임계자기장 값을 보이나 그 특성은 불안정하여 상온에 한번 노출되면 그 초전도 특성을 잃어버리게 된다. 이 논문에서는 Ga/Al 두층 박막을 제작하여 이러한 비정질 Ga 박막의 불안정한 초전도 특성을 개선할 뿐만 아니라 기존의 스핀검출에 응용되고 있는 Al 박막을 대체할 수 있는 가능성을 연구하였다. 극초진공 분자빔박막 증착장비(UHV-MBE)를 사용하여 Ga/Al 두층 박막을 제작하고, 표면의 적절한 플라즈마 산화 처리에 의한 Ga/Al/$Al_2O_3$/Fe의 터널 접합구조를 제작하여 Ga/Al 박막의 초전도 특성을 측정하였다. 한편, Ga/Al 박막의 표면 특성은 Auger 전자 분광기를 이용하여 분석하였다.

• BMB Reports
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• 제46권3호
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• pp.151-156
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• 2013

Phylogenetic and amino acid sequence analysis indicated that rice allene oxide synthase-1 (OsAOS1) is CYP74, and is clearly distinct from CYP74B, C and D subfamilies. Regio- and stereo-chemical analysis revealed the dual substrate specificity of OsAOS1 for (cis,trans)-configurational isomers of 13(S)- and 9(S)-hydroperoxyoctadecadienoic acid. GC-MS analysis showed that OsAOS1 converts 13(S)- and 9(S)-hydroperoxyoctadecadi(tri)enoic acid into their corresponding allene oxide. UV-Visible spectral analysis of native OsAOS1 revealed a Soret maximum at 393 nm, which shifted to 424 nm with several clean isobestic points upon binding of OsAOS1 to imidazole. The spectral shift induced by imidazole correlated with inhibition of OsAOS1 activity, implying that imidazole may coordinate to ferric heme iron, triggering a heme-iron transition from high spin state to low spin state. The implications and significance of a putative type II ligand-induced spin state transition in OsAOS1 are discussed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.1924-1926
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• 2005

Poly(methyl methacrylate) (PMMA) is one of the promising representive of polymer gate dielectric for its high resistivity and sutible dielectric constant. PMMA (Mw=96700) films were prepared on p-Si by spin coating method. PMMA were coated compactively and flatly as observes by AFM. MIS(Al/PMMA/p-Si) structure was made and capacitance-voltage (C-V) and current-voltage (I-V) measurements were done with PMMA films for repeated annealing cycles at $100^{\circ}C$. 1-V measured at various delay times $(0{\sim}20sec)$ showed little change and the absence of hysteresis in the I-V characteristics with delay times, which eliminate the possibility of deep traps in the PMMA films. The observed thermal stability, smooth surfaces, dielectric constant, I-V behavior implies PMMA formed by spin coating can be used as an efficient gate dielectric layer in OTFTs.