• 한국정밀공학회지
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• 제28권9호
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• pp.1086-1093
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• 2011

To fabricate the aluminum alloys with good drawability, the textures evolution of the AA5182 sheets due to the change of lid parameter after rolling and subsequent annealing was studied. The measurement of the deformation textures was carried out for the sheets with high reduction ratio and the change of the recrystallization texture was investigated after heat-treatments of the rolled sheets in various I/d parameters. Rolling without lubrication and subsequent annealing led to the formation of favorable rot-$C_{ND}$ {001}<110> and ${\gamma}$-fiber ND//<111> textures in AA5182 sheets. From the results, the ${\gamma}$-fiber ND//<111> component well evolved during rolling at high lid parameter of 6.77. The initial shear deformation texture, especially, ${\gamma}$-fiber ND//<111> was not rotated during heat treatment in holding time of 180~7,200 seconds on AA5182 with I/d parameter of 6.77. Therefore, the AA5182 sheets were fabricated by controlling I/d parameter having well evolved ${\gamma}$-fiber ND//<111> which was advantageous in good drawability of the sheets.

• 한국자동차공학회논문집
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• 제13권6호
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• pp.128-134
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• 2005

In order to fabricate the aluminum alloys with good drawability, the textures evolution of the AA5182 sheets after rolling and annealing was studied. The measurement of the deformation textures was carried out for the sheets which were cold rolled with high reduction ratio by using the symmetric roll. In addition, the change of the recrystallization texture was investigated after heat-treatments of the rolled sheets with various heat treatment conditions. Rolling without lubrication and subsequent annealing led to the formation of favorable $rot-C_{ND}\;\{001\}<110>\;and\;{\gamma}-fiber ND//<111>$ textures in AA5182 sheets. From the results, the ${\gamma}$-fiber ND//<111> component well evolved during rolling at highest reduction ratio (over $90\%$, l/d parameter of 6.77). Among shear deformation textures, the ${\gamma}$-fiber ND//<111> was not rotated in holding time of $180\~7,200$ seconds at $350^{\circ}C$. The Monte-Carlo technique was used and could be representatively simulated these textures evolution during recrystallization.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 추계학술대회 논문요약집
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• pp.111-111
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• 2003

• 한국결정성장학회지
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• 제9권1호
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• pp.1-5
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• 1999

Molecular beam epitaxy법으로 $CaF_{2}$ (111) 기판위에 희토류 이온 ($(Nd^{3+},\;Er^{3+})$) 첨가 $CaF_{2}$ 박막을 성장하였다. 첨가농도와 박막두께에 따른 희토류 첨가 $CaF_{2}$ 박막의 표면구조와 결정성을 RHEED로 검토하였다. 반도체 관련 고집적회로구조에 있어서의 완층막으로서의 응용을 고려하여, 희토류첨가 $CaF_{2}$ 박막과 $CaF_{2}$ (111) 기판과의 격자부정합의 변이를 X-ray rocking Curve 분석에 의해 검토하였다.

• 한국광학회지
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• 제9권3호
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• pp.175-180
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• 1998

고체 레이저매질로 가장 널리 쓰이는 Nd:YAG 단결정을 Czochralski 방법으로 육성하였다. 자체 제작한 Czochralski 결정 육성로 및 자동 결정 적경제어 장치를 써서 유효 직경 50mm, 길이 100mm의 Nd3+ 이온농도가 0.9at%이고 <111>방향의 단결정을 육성하였다. 단결정 육성시 융액의 수직방향에 대한 온도구배가 중용한 변수인 것이 확인되었으며, 결정 직경은 자동 제어가 가능하도록 컴퓨터 프로그램을 제작하였다. 육성된 단결정을 절단, 가공, 연마, 코팅 과정을 거쳐서 레이저 발진용 Nd:YAG막대를 제작하고 흡수 스펙트럼, 형과 스펙트럼 분석을 통하여 정확한 Nd:YAG의 레이저 발진특성을 확인하였다. 자체 가공된 레이저 막대로부터 발진된 CW 레이저의 최대 출력은 70W이었고, 발진문턱값과 효율은 각각 1.3kW, 1.64%이었다.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1998년도 PROCEEDINGS OF THE 14TH KACG TECHNICAL MEETING AND THE 5TH KOREA-JAPAN EMGS (ELECTRONIC MATERIALS GROWTH SYMPOSIUM)
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• pp.71-74
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• 1998

$Er^{3+}$ doped $NdF_{3}$ single crystalline thin films with smooth, microcrack-free, and high-crystalline quality were grown on $CaF_{2}(111)$ substrate at $500^{\circ}C$by molecular beem epitaxy(MBE). The relation-ship between subcell and supercell showing the reconstructed $3^{1/2} \times 3^{1/2}$ structure was studied by reflection high-energy electron diffraction(RHEED) investigation. The film surface and the growth mode were examined in studied by RHEED patterns and atomic force microscope(AFM) images ex situ. The crystallinity of film and the lattice mismatch between $NdF_{3}Er}^{3+}(0002)$ film and $CaF_{2}(111)$ substrate depending in the $Er^{3+}$ concentration were investigated by X-ray rocking curve analysis.

• 한국세라믹학회지
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• 제31권3호
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• pp.249-256
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• 1994

By surface structure and X-ray topographic observation, growth mechanism of NAB single crystal grown by TSSG technique using a BaB4O7 flux was studied. Surface structure of grown crystals were investigated by optical microscope. Growth history and crystal defects included within grown crystal were investigated using X-ray topography. The {001} faces were grown by 2-D nucleation growth. As decreasing cooling rate, growth mechanism of {111} and {11} was changed from 2-D nucleation growth to the growth by screw dislocation. Only surface striations developed parallel to a-axis were observed on {010} faces. Growth sector of NAB crystals were divided into {001}, {111}, {010}, {021}, {11}. The inclusion which was usually trapped between {001} faces was investigated.

• 한국세라믹학회지
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• 제30권8호
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• pp.643-650
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• 1993

NdAl3(BO3)4 have been developed for miniature solid state laser material. Single crystals of NdAl3(BO3)4 were grown by TSSG technique using BaB4O7 flux. The effects of growth conditions such as cooling rate, seed orientation and rotation speed on crystal quality and the morphology were studied. At the cooling rate of 2.4$^{\circ}C$/day and the crystal rotation speed of 30~40rpm with the seed orientation in <201> or <100> directions, transparent and light violet colored crystals in size of 10$\times$15$\times$20㎣ with well developed {010}, {111}, {111}, {021}, {001}, {102}, {112}, {021} faces were obtained. By X-ray diffraction analysis, the space group was determined as C2/c, and the X-ray powder data was obtained.

• 월간양계
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• 제36권10호통권420호
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• pp.111-115
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• 2004

최근 급격한 산란 저하로 인한 피해를 상담하는 농가들이 많아진 것을 보니 N도 문지이지만 전염성 기관지염(IB)이 심상치 않은것 같다. 최근의 분무 백신은 ND도 중요하지만 IB에도 동시에 초점을 맞추고 있다는 어느 원장님을 얼마 전 만났다. 현재 발병하고 있는 IB에 대해 상당히 효과적인 대처를 하고 있다는 생각을 하게 된다. 국가적 난제인 ND도 중요하지만 IB에 대한 농가들의 경각심과 대책도 필요하다는 생각을 다시 해보면서 이에 따른 백신 분무와 관련한 몇 가지 이야기를 해보고자 한다.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1992년도 춘계연구발표회 논문개요집
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• pp.110-111
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• 1992