• Journal of the Korea Computer Graphics Society
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• v.22 no.2
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• pp.20-26
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• 2016

This paper proposes an automatic hexahedral mesh generation method, in which internal medial surfaces are established to partition a region using the face-offsetting method. In order to test the usability of the suggested method, aspect ratios and Jacobians of the generated mesh for two models are evaluated and compared with ones from existing methods. It is verified that the proposed medial surface generation and partitioning scheme based on the face-offsetting method can be effectively used in the automatic hexahedral mesh generation procedure.

• Journal of the Korea Convergence Society
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• v.6 no.5
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• pp.9-14
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• 2015

In this paper, we analysis the electromagnetic scattering of an arbitrary shape dielectric cube subjected to plane wave incidence in three dimensions. MoM(Method of Moments)in which a surface of a body is divided with small triangular patches and equivalence principle are used to fuse the PMCHW(Poggio, Miller, Chang, Harrington, and Wu) Integral Equations with respect to equivalent currents on a dielectric body. Triangular patch and loop-patch basis functions that is robust in wide frequency ranges are used for MoM formulations. Proposed method is very useful to analysis the induced current of arbitrary dielectric bodies and numerical results for a dielectric cube are presented.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2002.05a
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• pp.231-235
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• 2002

본 논문에서는 전문 안무가와 일반인들을 대상으로, 현대적 스타일의 독무와 임의적으로 움직이는 육면체를 제시할 때의 두뇌 활동 양상을 fMRI를 통하여 알아보았다. 피험자들은 총 8명으로 구성되었으며, 4명은 안무 전문가들, 4명은 동일한 연령대의 일반인들이었다. 피험자들은 시각 자극으로 제시되는 춤동작과 다양하게 변화하는 단순한 육면체의 움직임을 아무런 반응 없이 보는 과제를 수행하였다. 두 피험자 그룹 모두에서 육면체의 움직임보다 무용을 응시할 때 occipital cortex에서 더 큰 활성화를 보였고, 특히 좌측 STS와 angular gyrus사이의 경계선 영역, 그리고 좌측 fusiform gyrus에서는 안무가들이 무용을 볼 때 일반인들보다 더 높은 활성화를 나타내었다. STS/angular gyrus와 fusiform gyrus가 시각 자극의 의미 표상을 이해하는데 관련이 있고, angular gyrus가 사전적 의미 해석에 있어 중계적 역할을 하는 곳이며, fusiform gyrus는 사물을 지각하는데 있어서 보조 역할을 맡고 있다는 논의를 바탕으로, 무용가들은 그들이 지니고 있는 안무에 대한 전문적인 소견과 지식을 이용하여 몸의 움직임을 분석할 수 있고, 또 그것에서부터 어떠한 상징적인 의미까지 끌어내어 결과적으로 의미 추출의 과정에서 두뇌의 semantic network를 활성화시킨다고 볼 수 있다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.517-521
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• 2000

본 논문에서는 영상 처리 방법을 이용하여 주어진 객체의 실세계 좌표를 나타내는 특징점을 인식하는 한 방법을 제안한다. 제안된 방법에서는 육면체 형상의 객체를 대상으로 하며, 이러한 객체 영상의 주요한 특징점은 육면체를 결정짓는 꼭지점들로 이루어진다. 제안된 방법은 CCD 카메라로부터 영상을 획득하는 영상 획득 모듈, 획득된 영상에 대하여 관심 영역을 찾는 영상 분할 모듈, 분할된 관심 영역에 대하여 sobel operator등을 이용하여 경계 정보를 검출하는 영상 처리 모듈, 그리고 세선화, line fitting과정을 통하여 직선 벡터들을 검출한 후에 객체의 주요한 특징점을 인식하는 모듈로 구성된다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.6
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• pp.329-334
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• 2002

The $CaTio_3$powder with perovskite structure was synthesized by mixing anatase $TiO_2$and $Ca(OH)_2$powders as starting materials, and KOH or NaOH as mineralizer, followed by hydrothermal method. The change of crystal structure, particle shape and size of the synthesized $CaTiO_3$powder was investigated with kind and concentration of mineralizer. It was found that the spherical particles of 0.7 $\mu$m were obtained when using 1N KOH and the hexahedrons particles of 3$\mu$m were obtained for the case of using 10 N KOH. With increasing KOH concentration, the particle shape was changed from sphere to hexahedrons and its size also increased. When using 1 N NaOH, the powder was consisted of 0.5~1 $\mu$m particle in size, whereas hexahedrons of 1~4 $\mu$m and whiskers more than 10$\mu$m in size was obtained for the 10 N NaOH solution. With increasing NaOH concentration, the particle shape was varied from hexahedrons to whiskers, showing the similar result with the KOH case. It was confirmed from EDS analysis that Na element, which was detected in hexahedrones was not contained in the whiskers.

• Journal of Power System Engineering
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• v.16 no.1
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• pp.78-83
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• 2012

The authors suggest the algorithm for the static analysis of a three dimensional solid structure by using the finite element-transfer stiffness coefficient method (FE-TSCM) and the hexahedral element of the finite element method (FEM). MATLAB codes were made by both FE-TSCM and FEM for the static analysis of three dimensional solid structure. They were applied to the static analyses of a very thick plate structure and a three dimensional solid structure. In this paper, as we compare the results of FE-TSCM with those of FEM, we confirm that FE-TSCM introducing the hexahedral element for the static analysis of a three dimensional solid structure is very effective from the viewpoint of the computational accuracy, speed, and storage.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1637-1641
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• 2007

In this paper, we simulate a rotor pole cold forging process by a forging simulator with both tetrahedral and hexahedral element capabilities and compare the predictions obtained by the two approaches with the experiments. Hexahedral element capability runs manually while tetrahedral element capability runs automatically with help of an intelligent remeshing technique. It is shown that the tetrahedral element capability can give quite accurate solution if assisted by the intelligent remeshing technique even though the tetrahedral element itself is not theoretically and numerically clear.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.2864-2866
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• 2005

색역폭 사상은 디스플레이 장치간의 색재현성 차이를 보정하기 위한 기법이다. 본 논문에서는 사면체 보간에 의한 실시간 색역폭 사상을 제안하고자 한다. 기존의 제안된 육면체 보간 방식에 비해 이 논문에서 제안된 사면체 보간(tetrahedral interpolation) 방법은 색공간의 분할을 통해 분할된 각각의 사면체 색 공간에서 색역폭 사상이 수행됨으로서 왜곡이 감소되고 육면체 보간이 8개의 룩업테이블을 사용하는데 비해 4개의 룩업 테이블을 사용함으로서 실시간 처리속도의 향상과 하드웨어의 구현 시 비용절감을 기대할 수가 있다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.423-424
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• 2006

This paper proposes a hexahedral mesh generation scheme based on mapping approach and improves the drawback of sweeping algorithm. In order to improve the drawback, the algorithm in this paper generates hexahedral meshes by three dimensional element mapping first. Then hexahedral meshes are equivalent to geometry of the volume by mapping and smoothing. Sample meshes are constructed to demonstrate the mesh generating capability of the proposed algorithm.

• Journal of the Korean Solar Energy Society
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• v.31 no.1
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• pp.44-50
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• 2011

The solar radiation, inner temperature of the tilted box and the amount of condensed water were measured to find the most effective purified water production system. The inner temperature of the tilted box was related with solar radiation that was affected by sunshine and cloud. With analyzing those relationships of the solar radiation, inner box temperature, the angle of tilted boxes and amounts of water condensation optimal collecting system area could be calculated.