• Electronics and Telecommunications Trends
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• v.31 no.1
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• pp.134-145
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• 2016

최근 3D 프린팅이 제조업의 혁신을 이끌 새로운 키워드로 주목을 받으면서 하드웨어인 3D 프린터를 비롯해 각종 프린팅 재료, 프린팅 대상을 만들 수 있는 3D 저작 및 편집 소프트웨어에 이르기까지 관련 분야에 대한 관심과 지원이 빠르게 확산되는 추세다. 특히, 개인의 아이디어를 3D 프린터로 직접 출력할 수 있다는 점이 강조되면서 개인용 3D 콘텐츠 제작을 위해 필요한 저작/편집도구의 수요가 급격히 증가하고 있다. 더불어 3D 프린팅 출력 대상이 개인화되고 사용자의 기호에 따른 맞춤형으로 변하면서, 3D 콘텐츠 제작에 필수적인 소프트웨어 개발 업체의 영향력이 하드웨어 제조사보다 더욱 커지고 있다. 3D 프린팅 관련 세계적 기술 및 수요 변화에 발맞춰 본고에서는 3D 프린팅용 콘텐츠를 제작할 수 있는 3D 저작/편집도구 및 연구동향을 살펴보고, 다양한 응용을 목적으로 ETRI에서 개발 중인 3D 프린팅용 편집기술을 소개하고자 한다.

• Journal of the Korean Chemical Society
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• v.22 no.3
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• pp.158-163
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• 1978

The four 1,1-disubstituted 2-vinylcyclopropanes, 1,1-diphenyl-2-vinylcyclopropane (1a), 1,1-dicyano-2-vinylcyclopropane(1b), ethyl 1-cyano-2-vinylcyclopropanecarboxylate(1c), and diethyl 2-vinylcyclopropane-1,1-dicarboxylate(1d) rearranged below $300{\circ}C$ to the corresponding 4,4-disubstituted cyclopentenes, 4,4-diphenylcyclopentene(2a), 3-cyclopentene-1,1-dicarboxylate(2d). Diphenpyl derivative 1a rearranged almost quantitatively to 4,4-diphenylcyclopentene(2a) at the temperature of $250{\circ}C$. Although dicyano derivative 1b in solution underwent the thermal rearrangement at rather low temperature of $170{\circ}C$, the other vinylcyclopropanes, 1c and 1d, in solution rearranged thermally above $220{\circ}C$. In the thermal reaction of 1b, 1c, and 1d considerable amounts of polymers 3 were also produced. Also detected product was the ring-opened diene, ethyl 2-cyano-2,4-hexadienoate(4), in case of the pyrolysis of 1c. The observed facile rearrangement of disubstituted vinylcyclopropanes was explained by the radical stabilization effect of substituents on the diradical intermediates 5.

• Journal of the Korean Ceramic Society
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• v.32 no.9
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• pp.1003-1008
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• 1995

CVD-Si3N4/CVD-SiC/pack-SiC/pyro-carbon/(3-D C/C composite) multilayer coating was performed to improve the oxdiation resistance and erosion resistance properteis of the 3-D carbon/carbon composite, and the plasma test was performed to measure the oxidation resistance and erosion resistance properties. The thicknesses of each film layer were about 10${\mu}{\textrm}{m}$ for pack-SiC, 5${\mu}{\textrm}{m}$ for CVD-SiC and 40${\mu}{\textrm}{m}$ for CVD-Si3N4. When the multilayer coated specimen was exposed to the plasma flame with temperature of 500$0^{\circ}C$ for 20 seconds, it showed the weight loss five times less than that of the only pyro-carbon coated specimen.

• Journal of the Korean Chemical Society
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• v.34 no.6
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• pp.517-526
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• 1990

The crystal structures of two alditol acetates, D-glucitol hexaacetate and xylitol pentaacetate, have been determined by diffraction methods with Mo-K$\alpha$radiation, using direct methods for phase determinations. The crystal data are: for D-glucitol hexaacetate, P2$_1$, with a = 10.275 (2), b = 8.363 (1), c = 12.560 (5) $\AA;\beta$ = 95.97 $(2)^{\circ}$, Z = 2; for xylitol pentaacetate, P2$_1$/C with a = 18.126 (1), b = 11.422 (2), c = 8.649 (1) $\AA$, $\beta = 95.03 (1)^{\circ}$, Z = 4. Both molecules have extended zigzag carbon chain conformations which differ from previous studies of the structures of D-glucitol and xylitol and also differ from NMR studies on alditol acetates. The bond lengths and angles are normal, with mean values over both structures of C($sp^3)-C(sp^3): 1.514 (10),\; C(sp^3)-O: 1.444 (6),\; C(sp^2)-O: 1.347 (9),\; C(sp^2)=O: 1.197 (6),\; C(sp^2)-C(sp^3): 1.479(9){\AA},\; C(sp^3)-C(sp^3)-C(sp^3): 114.6 (17),\; O-C(sp^3)-C(sp^3): 109.4 (23),\; C(sp^2)-O-C(sp^3): 117.4 (6),\; O=C(sp^2)-O: 122.6 (6),\; C(sp^3)-C(sp^2)-O: 111.8 (7),\; C(sp^3)-C(sp^2)=O: 125.5 (4)^{\circ}$. The atoms of acetate groups are in coplanar. There are no particularly short intermolecular contacts and the molecules are held together by van der Waals force only.

• Journal of KIISE:Software and Applications
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• v.33 no.9
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• pp.741-750
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• 2006

In this paper, we propose a method for reconstructing a 3D object (or a set of objects) from a 2D drawing provided by a designer. The input 2D drawing consists of a set of contours that may partially overlap each other or be self-overlapping. Accordingly, the resulting 3D object(s) may occlude each other or be self-occluding. The proposed method is composed of three major steps: 2D contour analysis, 3D skeleton computation, and 3D object construction. Our main contribution is to compute the 3D skeleton from the self-intersecting 2D counterpart. We formulate the 3D skeleton construction problem as a sequence of optimization problems, to shape the skeleton and place it in the 3D space while satisfying C1-continuity and intersection-free conditions. Our method is mainly for a silhouette-based sketching interface for the design of 3D objects including self-intersecting objects.

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.61.2-61.2
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• 2007

• Proceedings of the Korean Society of Crop Science Conference
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• 1989.02a
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• pp.50-51
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• 1989

• 대한핵의학회:학술대회논문집
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• 1990.04a
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• pp.193.1-193.1
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• 1990

• 대한핵의학회:학술대회논문집
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• 1989.06a
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• pp.137.2-137.2
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• 1989

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.611-612
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• 2006