• Journal of the Korean Chemical Society
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• v.36 no.3
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• pp.366-375
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• 1992

The aminolysis of carbamates are studied MO theoretically using AM1 method. The results indicated that the reactivity is determined by bond-making and-breaking and steric effects; as a result the $B_{AC}2$ mechanism is favored due to favorable contribution of bond formation in agreement with experimental results. We found that although thermal 2＋2 reaction is forbidden, it becomes allowed when the total electrons involved are six in a four-center reaction and proceeds by a consecutive onestep mechanism. Comparison of activation barriers show that greater energy is required in breaking a sigma bond compared with the energy required for breaking a $\pi$ bond, by 17 kcal/mol and the six membered ring structure is favored about 5 kcal/mol sterically.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.12
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• pp.2865-2874
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• 2013

Recently, most of movies top-ranked in the box office are screening in Stereoscopic 3D, and the world's leading electronics companies such as Samsung and LG are getting the hots for 3DTV sales. However, each person has different binocular disparity and different viewing distance, and thus he or she feels the severe visual fatigue and headaches if he or she is watching 3D content with the same binocular disparity, which is very different from things he or she feels in the real world. To solve this problem, this paper proposes and implement a 3D rendering system that correct the disparity of 3D content by reflecting binocular distance and viewing distance. Then, the computational complexity is analyzed. Optical-flow and Warping algorithms turn out to consume 732 seconds and 5.7 seconds per frame, respectively. Therefore, a dedicated chip-set for both blocks is strongly required for real-time HD 3D display.

• Elastomers and Composites
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• v.35 no.3
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• pp.205-214
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• 2000

The polyurethane resin was prepared by the reaction of tolylenediisocyanate(TDI) and polypropyleneglycol(PPG). Physical properties of the resin were investigated experimentally. Charging catalyst before TDI-dropping induced the rapid increase of viscosity. On the other hand, charging catalyst after TDI-dropping resulted in mild stability without immoderate generation of heat on reaction. The use of phosphoric acid as catalyst led to low viscosity by restraining side-reaction such as forming of branch-chain, buret reaction and allopanate reaction, but it showed low cross-link density and slow drying. The curing speed was more influenced by structures of molecules rather than NCO/OH ratio. Including PPG 400 over 30 wt % showed excellent adhesive strength due to increase of crosslink density.

• The Journal of the Convergence on Culture Technology
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• v.7 no.2
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• pp.389-394
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• 2021

In this work, we study the properties of molecular structure and boundary orbital functions of the DPHMP-AlH and propiophenone and butyrophenone, which are forms of alkoxy-amine-aluminum derivatives. Furthermore, we investigate the effect on the selective reduction of the final products (R), (S)-phenylpropanol and (R), (S)-phenylbutanol by calculating the stereoscopic and thermodynamic parameters of the transition state. Considering the three-dimensional molecular structural stability, the transition status of (S) types DPHMP-AlH and alkylphenone was found to be more stable, resulting in the selective reductions of DPHM-AlH and alkylphenone from this result: (S)-(1)-phenylpropanol and (S)-(1)-phenylbutanol was confirmed that the formation was advantageous.

• Korean Journal of Veterinary Research
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• v.32 no.2
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• pp.207-210
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• 1992

Oral infection of colostrum-deprived, neonatal piglets with porcine enterovirus serotype 3 can result in hepatic lesions with a short incubation period. In the thin section of the affected liver, crystalline arrays of virus particles characteristic of picornavirus were identified in the sinusoid endothelial cells and Kupffer cells. There were also cytoplasmic aggregates of electron- dense, virus-like particles in the hepatocytes. These findings suggest that porcine enterovirus serotype 3 has hepatotropism as well as neurotropism.

• Journal of Educational Research in Mathematics
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• v.13 no.4
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• pp.495-506
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• 2003

In this study, 1 investigated some properties on the special hyper-dimensional figures made by the principle of the performance of equivalent forms representation. I supposed 2 definitions on the making n-dimensional figure : a cone type(hypercube) and a pillar type(simplex). We can explain that there exists only 6 4-dimensional regular polytopes as there exists only 5 regular polygons. And there are many hyper-dimensional figures, they all have sufficient condition to show the general Euler' Characteristics. And especially, we could certificate that the simplest cone type and pillar types are fitted to Pascal's Triangle and Hasse's Diagram, each other.

• Journal of Broadcast Engineering
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• v.14 no.1
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• pp.85-88
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• 2009

Recently "DMB Video-Associated Stereoscopic Data Services" standard has been published by TTA. The standard enables DMB broadcasters to provide 3D or stereoscopic interactive data services based on MPEG-4 BIFS (Binary Format for Scenes). The purpose is to entice viewers to utilize DMB interactive data services more often by providing realistic and protrusive image objects overlaid on top of the main video in the background. This paper provides the background, technical analysis, and in-depth considerations for the standard. Also the results of standard verification are provided including the results of interoperability test with the existing terrestrial DMB receivers.

• Journal of Industrial Convergence
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• v.17 no.4
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• pp.69-75
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• 2019

In this study, we developed a world map learning system for elementary education that uses Google Cloud platform STT, Dialog Flow, and fan holograms to recognize the voices of learners and to show and explain three-dimensional images of suitable results as holograms. As a result of the experiments and interviews, it is expected to be helpful for improving the learning effect by inducing students' interest and immersion and is expected to be effectively used for collaborative learning and education for students with disabilities.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2012.11a
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• pp.44-45
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• 2012

좌우 해상도가 차이나는 융합형 3DTV의 화질을 개선하기 위한 기법으로써 두 영상간의 양안시차 정보를 활용하는 조건부 대체 알고리즘이 제안된 바 있다. 본 논문에서는 양안시차 벡터의 정밀도가 조건부 대체 알고리즘에 미치는 영향을 살펴보기 위해 양안시차 벡터 추정에 사용되는 좌영상의 해상도에 따른 알고리즘의 성능을 비교한 실험결과를 제시하였다. 높은 해상도의 좌영상을 사용하여 양안시차 벡터의 정밀도가 높아질수록 확장된 우영상의 객관적 화질 및 합성된 3D영상의 자연스러운 입체감이 향상됨을 확인하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.34-34
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• 2018

레이저를 통한 플라스틱 일체형 회로형성 기술은 레이저 직접 성형 (Laser Direct Structuring, LDS) 기술과 도금기술을 이용하여 기판 표면에 전도성 회로 패턴을 형성하고 소자를 집적하여 부품을 제작하는 기술이다. 종래에는 PCB 기반의 평면기판을 기반으로 하여 제작된 소자와 부품이 전자제품의 주를 이루었으나, 최근 소자의 집적화와 제품 디자인의 유연화(flexible)로 굽힘(bendable) 형태의 스마트 시계와 같은 웨어러블(wearable) 전자 제품이 출시되었으며, 레이저를 통한 플라스틱 일체형 회로형성 기술은 미래 사회의 주를 이룰 웨어러블 형태의 제품의 상용화를 가능하게 할 뿐만 아니라 회로 집적이 가능하여 제품 혁신을 주도할 기술로 주목 받고 있다. 본 연구에서는 LDS 부품의 미세 회로 구현을 위한 공정 기술 개발에 있어서 고생산성 무전해 동도금액 및 부품 실장을 위한 표면처리 기술 개발에 대한 결과를 보고한다. 미세 회로 패터닝 기술의 상용화를 위해서는 도금액의 안정성뿐만 아니라 고속 공정기술이 필요하다, 현재 국내 무전해 동 도금의 석출 속도는 시간 당 $4{\sim}5{\mu}m$ 내외이기 때문에, 생산성을 향상시키기 위해서는 시간 당 $10{\mu}m$ 정도의 고속 무전해 동 도금 공정 개발 필요하다.