• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.3
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• pp.349-358
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• 1997

meta-Nitroaniline(mNA) crystals were grown from the supercooled melt for the first time. A seed was introduced into the purified mNA melt of 100 ml 0.1 K above the melting temperature ($T_m$ : $112.0^{\circ}C$) and crystal was grown at constant supercooling of 0.1 K. The melt was stirred . mechanically and the crystal was also rotated while the growth proceeds. mNA crystals of size up to $20{\times}15{\times}15 \textrm {mm}^3 and of very high perfection could be grown for the period of one day. The bottom half of the crystal faces are well-faceted and covered by {111} and {021} faces, while the faces of the top half are not well defined. The overall crystal morphology was characterized by the unidirectional growth along one of the polar axes. The absolute direction of preferred growth was determined to be [001] by the pyroelectric measurements. The perfection of the crystal was characterized by synchrotron X-ray topography and optical characterization was made by measuring second harmonic conversion efficiency.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.3
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• pp.406-417
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• 1997

A numerical study was conducted on the optimum magnetic field intensity and asymmetric factor for uniform axial oxygen concentration in 8 inch silicon single crystal growing process by magnetic Czochralski method. For constant shape of cusp field, a change of coil and crucible position were compared. In case of symmetric cusp field, magnetic field intensity variation shows concave downward with crystal growing for uniform, axial oxygen concentration. A numerical results show similar value of standard deviation of average oxygen concentration for uniform oxygen concentration between coil and crucible position change. In case of asymmetric cusp field. asymmetric factor is increased with crystal growing to have uniform oxygen concentration.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.1
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• pp.44-49
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• 1995

Abstract The surface of 6H - SiC bulk crystal grown by sublimation process was investigated by optical microscope observation. Since, in the 6H crystal growing, the crystal had the habitual step growth attitude such that the lateral growth rate along the random a - axis orientation was higher than that along the c - axis of the growth direction, then many steps were developed. There were, also, many micropipes on the surface in the form of as-like large voids. However, they were differenciated with pores and cross- sectional shape of them were close to the circle. In this study, many micropipes, planar defects and the growth steps appeared on the grown crystal surface were investigated.

• Journal of Broadcast Engineering
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• v.14 no.3
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• pp.342-356
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• 2009

This paper presents a vote decision-based deinterlacing scheme for false directional error correction(VDD) to convert interlaced signal into non-interlaced signal using only one fields. The VDD using the vote decision goes through four steps process. The first step extracts regions having doubt of false edge using MM-ELA method. In these regions, the edge direction is decided by the majority vote using upper adjacent pixels's information through the second step. But, we still have undecided directions, which will be decided by the majority vote and the directional average decision at the third step. This step preserves the edge directions and minimizes visual degradation. Finally, the last step interpolates undecided pixels using DOI method which can consider the fine edge direction. Although the VDD with hierarchical structure has a high complexity, it can extract delicate edge compared to other pixel-by-pixel or window-by-window deinterlacing algorithms. Simulation results show that it has significantly improved both the subjective and objective qualities of the reconstructed images.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.365-365
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• 2012

스퍼터된 a축 성장된 산화아연 박막의 전기적 및 구조적 특성의 DC 파워에 대한 영향을 c 축 성장된 산화아연 박막과의 비교를 통해 분석하였다. 1~103 ${\Omega}{\cdot}cm$의 낮은 비저항을 갖는 파워를 갖는 조건과 106~108 ${\Omega}{\cdot}cm$의 높은 비저항을 갖는 파워를 갖는 조건에 대한 분석을 진행하였다. 각 조건에 따른 XRD 분석을 통해 낮은 비저항을 갖는 파워를 갖는 조건의 경우 (100) 성장 방향을 강하게 나타내었으나, 높은 비저항을 갖는 파워를 갖는 조건의 경우 약한 (002) 성장 방향을 나타내었다. EDS를 이용한 분석시 낮은 비저항을 갖는 파워의 경우 상대적 으로 oxygen rich 특성을 나타내었다. 이번 연구를 통해 비저항 등 다양한 조건에 따라 결정 성장 방향이 다름을 확인하였으며, 이에 대한 분석을 통해 산화아연 박막의 성장된 조건에 따 라 다양한 전자소자에의 응용 및 분석이 필요함을 확인하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06b
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• pp.66-68
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• 2012

적의 주타격 방향은 적 지휘관의 주요 결정사항 중에 하나이다. 이런 적의 주타격 방향에 영향을 미치는 요소들을 분석하여 예측할 수 있다면 전쟁에서 좀 더 유리한 여건을 조성할 수 있을 것이다. 그러나 현재 군에서는 과학적 분석방법이 아닌 분석관 및 지휘관의 경험에 의한 적 주타격 방향 분석이 주를 이루고 있다. 따라서 본 논문에서는 데이터 마이닝의 대표적 방법인 의사결정트리의 C4.5 알고리즘을 사용하여 북한군의 지휘관 결심지도를 분석하였다. 또한 도출된 분류 규칙을 통해 적 주타격 방향 영향요소를 식별하고 영향요소들 간의 관계 및 정도의 수준을 예측하였다. 분석결과 현재 군에서 사용하고 있는 정보와 유사하고 의미 있는 정보를 도출할 수 있었다.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.10a
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• pp.1776-1777
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• 2015

본 연구에서는 3D 객체의 수직 방향(upright orientation)과 오버행(overhang) 면적을 고려하는 3D 프린팅 방향 최적화 방법을 제안한다. 모든 메시 법선들을 세 그룹으로 분류함으로써 객체의 수직방향을 계산한 후, 객체의 무게 중심과 3D convex hull을 사용하여 세 개의 후보 방향을 결정한다. 각 후보 방향에 대하여 오버행 메시 면적을 계산하고 최소 면적을 갖는 후보를 최종 프린팅 방향으로 결정한다. 후보 방향들을 적용하여 회전시킨 모델을 Cura에서 로드하여 프린팅 시간을 가측정한 결과, 제안 방법에 의해 최적화된 방향이 가장 짧은 시간이 소모되는 것으로 나타났다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.1
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• pp.84-88
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• 1999

The behavior of oxygen precipitation was investigated in radial direction using Si wafers with different vacancy-related defects generation area. The behavior of oxygen precipitation in radial direction is strongly dependent on the size of vacancy rich area which is related with crystal growth condition. Oxygen precipitation rate is more enhanced in vacancy rich area than that of interstitial rich area. And anomalous oxygen precipitation is generated in the marginal bands of vacancy and interstial area. In V/I boundary, however, oxygen precipitation is suppressed to nearly perfect.

• Korean Journal of Crystallography
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• v.4 no.2
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• pp.49-53
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• 1993

A converuent crystal orientation method for oscillation shot ograchy using de Jong Boumancamera is presented The method involves the measuremint of the deviations of resection spots of Oth layer from the equator These deviations are added or subtracted to give the horizontal and vertical arc corrections.

• Journal of Korea Game Society
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• v.11 no.6
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• pp.61-70
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• 2011

In this paper, we propose a defense NPC control model in the soccer game by applying the Decision Tree learning algorithm. The proposed model extracts the direction patterns and the action patterns generated by many soccer game users, and applies these patterns to the Decision Tree learning algorithm. Then, the proposed model decides the direction and the action according to the learned Decision Tree. Experimental results show that the proposed model takes some time to learn the Decision Tree while the proposed model takes 0.001-0.003 milliseconds to decide the direction and the action based on the learned Decision Tree. Therefore, the proposed model can control NPC in the soccer game system in real time. Also, the proposed model achieves higher accuracy than a previous model (Letia98); because the proposed model can utilize current state information, its analyzed information, and previous state information.