• Title/Summary/Keyword: representation sphere

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Fundamental Condition for the Realization of Maximal Contrast and Brightness in Liquid Crystal Display Devices: I. Monochromatic Case (액정표지소자에서 화면의 명암대비와 밝기를 극대화하는 기본조건: I. 단색광의 경우)

  • 노봉규;김규석;김진승
    • Korean Journal of Optics and Photonics
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    • v.5 no.3
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    • pp.404-410
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    • 1994
  • The contrast and the brightness of a liquid crystal display panel are expressed in terms of the characteristic parameters of the rotational transformation on the Poincare sphere of the liquid crystal (LC) cell, which is the geometric representation of the electro-optic polarization transmission characteristics of the cell. From these, we show that the contrast and the brightness of the displayed images can be maximized when the rotation angle becomes $180^{\circ}$ for the rotational transformation corresponding to the change of the state of the LC cell from non-select to select state. state.

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A STUDY OF INCOMPRESSIBLE VISCOUS FLOW ANALYSIS BY VORTEX-IN-CELL METHOD (보오텍스 인 셀 방법을 이용한 점성유동해석 연구)

  • Lee, J.H.;Kim, Y.C.;Lee, K.J.;Suh, J.C.
    • 한국전산유체공학회:학술대회논문집
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    • 2011.05a
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    • pp.78-85
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    • 2011
  • The Vortex-In-Cell(VIC) method combined with panel method is applied to the analysis of incompressible unsteady viscous flow. The dynamics of resulting flow is governed by the vorticity transport equation in Lagrangian form with vortex particle representation of the flow field. A regular grid which is independent to the shape of a body is used for numerical evaluation based on immersed boundary technique. With an introduction of this approach, the development and validation of the VIC method is presented with some computational results for incompressible viscous flow around two or three dimensional bodies such as wing section, sphere, finite wing and marine propeller.

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New Geometric modeling method: reconstruction of surface using Reverse Engineering techniques

  • Jihan Seo
    • Proceedings of the Safety Management and Science Conference
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    • 1999.11a
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    • pp.565-574
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    • 1999
  • In reverse engineering area, it is rapidly developing reconstruction of surfaces from scanning or digitizing data, but geometric models of existing objects unavailable many industries. This paper describes new methodology of reverse engineering area, good strategies and important algorithms in reverse engineering area. Furthermore, proposing reconstruction of surface technique is presented. A method find base geometry and blending surface between them. Each based geometry is divided by triangular patch which are compared their normal vector for face grouping. Each group is categorized analytical surface such as a part of the cylinder, the sphere, the cone, and the plane that mean each based geometry surface. And then, each based geometry surface is implemented infinitive surface. Infinitive average surface's intersections are trimmed boundary representation model reconstruction. This method has several benefits such as the time efficiency and automatic functional modeling system in reverse engineering. Especially, it can be applied 3D scanner and 3D copier.

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The Study on Reconstruction of Composite Surfaces by Reverse Engineering Techniques (Reverse Engineering 기술을 적용한 복합면의 재구성 정보 추출을 위한 연구)

  • Seo, Ji-Han;Lee, Hong-Chul;Shone, Young-Tea;Park, Se-Hyung
    • IE interfaces
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    • v.12 no.2
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    • pp.205-209
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    • 1999
  • In reverse engineering area, the reconstruction of surfaces from scanned or digitized data is being developed, but geometric model of existing objects is not available in industries. This paper presents the new approach to the reconstruction of surface technique. A proposed methodology finds base geometry and blends surface between them. Each based geometry is divided by tri-angular patches which are compared with their normal vector for face grouping. Each group is categorized analytical surface such as a part of cylinder, sphere and cone, and plane shapes to represent the based geometry surface. And then, each based geometry surface is implemented to the infinitive surface. Infinitive surface's intersections are trimmed by boundary representation model reconstruction. This method has several benefits such as time efficiency and automatic functional modeling system in reverse engineering. Especially, it can be directly applied 3D fax and 3D copier.

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Characterization of a Tunable Flattened-Pass-band Fiber Comb Filter

  • Lee, Yong Wook;Jung, Jaehoon
    • Current Optics and Photonics
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    • v.3 no.2
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    • pp.111-118
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    • 2019
  • The optical characteristics of a tunable flattened-pass-band fiber comb filter, based on the polarization-diversified loop configuration, are investigated using the $Poincar{\acute{e}}$-sphere representation. In the design process, the spectral flatness is checked quantitatively, and the tunability of the pass band is demonstrated experimentally. Theoretical calculations show that the filter also exhibits desirable dispersion and polarization properties. The orientation angles of rotatable wave plates for the wavelength tunability of the filter are obtained. Furthermore, we elaborate on the multiple angle loci produced by degeneracies through the combination of optical elements within the loop of the filter.

Matching for the Elbow Cylinder Shape in the Point Cloud Using the PCA (주성분 분석을 통한 포인트 클라우드 굽은 실린더 형태 매칭)

  • Jin, YoungHoon
    • Journal of KIISE
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    • v.44 no.4
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    • pp.392-398
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    • 2017
  • The point-cloud representation of an object is performed by scanning a space through a laser scanner that is extracting a set of points, and the points are then integrated into the same coordinate system through a registration. The set of the completed registration-integrated point clouds is classified into meaningful regions, shapes, and noises through a mathematical analysis. In this paper, the aim is the matching of a curved area like a cylinder shape in 3D point-cloud data. The matching procedure is the attainment of the center and radius data through the extraction of the cylinder-shape candidates from the sphere that is fitted through the RANdom Sample Consensus (RANSAC) in the point cloud, and completion requires the matching of the curved region with the Catmull-Rom spline from the extracted center-point data using the Principal Component Analysis (PCA). Not only is the proposed method expected to derive a fast estimation result via linear and curved cylinder estimations after a center-axis estimation without constraint and segmentation, but it should also increase the work efficiency of reverse engineering.

A Study on the Construction of Modern Architectural Form and the Characteristics of Deconstructional Fashion (현대 건축의 형태구성과 해체주의 패션의 특성에 관한 연구)

  • 김혜정;임영자
    • Journal of the Korean Society of Costume
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    • v.40
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    • pp.137-147
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    • 1998
  • Fahion as the form construction of decon-structivistic architecture was analyzed by dividing it into the intrinsic aspect and the formal aspect through an introduction of three characteristic architectural principles into fashion. Intrinsic deconstructivistic fashion as the construction of architectural form has the mixurte of genders both in a form of transvestic and in a form of genderless look as dualism, and can be characterized by pluralistic nationlism with the emergence of the Third World alienated from the international society, and so forth. Difference and the prefixes of dis-and de- are schizophrenic mystic illusionism, chance effect and the differance of space and time and is supporting Jacques Derrida's chiasmus that is the perspective of collage in painting and the multiple observation of collage in painting and the multiple observation point as the play of borrowing the surrealistic technique. The formal construction of deconstructivistic fashion the construction of architectural form has intertextuality material, hybridization of items and the blending of modes and another sphere. Trace as icon deconstrucion attains historical analysis. Dis and de in fashion are showing the retrogre-ssion of gravity through decomposition, decon-tinuity and disjunction emerge nonstructural silho-uette, juxtaposition, inversion and replace- ment of underwear and outer garments. Their decentring expression emerged as construction through mixture and repetition as well as overlapping of planes or spaces. And their disjuctive representation appeared in the form of mutual juxtaposition and substitution with the double-side of formal construction in functional terms.

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Improved Rendering on Spherical Coordinate System using Convex Hull (컨벡스 헐을 이용한 개선된 구 좌표계 기반 렌더링 방법)

  • Kim, Nam-Jung;Hong, Hyun-Ki
    • Journal of Korea Game Society
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    • v.10 no.1
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    • pp.157-165
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    • 2010
  • This paper presents a novel real-time rendering algorithm based on spherical coordinate system of the object using convex hull. While OpenGL rendering pipeline touches all vertices of an object, the proposed method takes account the only visible vertices by examining the visible triangles of the object. In order to determine the visible areas of the object in its spherical coordinate representation, the proposed method uses 3D geometric relation of 6 plane equations of the camera frustum and the bounding sphere of the object. In addition, we compute the convex hull of the object and its maximum side factors for hidden surface removal. Simulation results showed that the quality of result image is almost same compared to original image and rendering performance is greatly improved.

Gender, Crime, (Woman) Detective: Sexual Politics of Early British and American Detective Fiction (젠더, 범죄, (여성)탐정 -초기 영미 추리소설의 성정치학)

  • Gye, Joengmeen
    • Journal of English Language & Literature
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    • v.56 no.5
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    • pp.931-946
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    • 2010
  • This paper examines the role of gender ideology in early British and American detective fiction focusing on the female detectives. Since a detective's attributes honor and idealize such traditionally masculine qualities as independence, intelligence, heroism, and bravery, the woman detective fiction has potentiality to operate against the established gender norms. The narratives about women in pursuit of justice and order through their criminal investigation can allow women to possess the masculine rationality and power. The subversive possibility inherent in the woman detective fiction is, however, contained by the representation of the female detectives and the negotiation through narratives. A female detective is represented either as unfeminine and thus unattractive and unlikeable or as desperate for survival. Her threatening potentiality is easily dismissed as that of an inadequate woman or a desperate one. The compromise in narratives is effected by the following three ways: first, a female detective is assigned to investigate crimes as an assistant to the male detectives; second, staying within the domestic sphere, she solves crimes by using her expert knowledge of the domestic service; and third, her detective narrative ends with the conventional marriage plot. Confining the female detectives within the conventional feminine roles and domains, the woman detective fiction supports and reestablishes the dominant gender ideology.

Public Art and Urban Reimagineering : An Evaluation of Busan Biennale 2006 (공공예술과 도시 재이미지화 : 2006 부산 비엔날레 평가)

  • Choi, Byung-Doo
    • Journal of the Korean association of regional geographers
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    • v.13 no.5
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    • pp.543-562
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    • 2007
  • Busan Biennale, began from 2000, has been argued that it would improve 'intrinsic introspection related to localism' against 'a lifestyle forced by capitalism in a global dimension', by promoting urban esthetic imagination in the public sphere of the city and reflecting it upon exhibited artworks. But Busan Biennale seems to reflect partly an attempt for new place marketing or urban reimagineering as a part of postmodern culture, even thought it has been planned to be an authentic stage or public-place art for citizens. This paper is to examine Busan Biennale 2006, held from Sep.16 to Nov.25 in Busan main theme of which is 'everywhere', constituted with three major projects: the Contemporary Art Exhibition, Sea Art Festival, and the Busan Sculpture Project. Ths paper considers first some implications of the transformation of modem to postmodern city, focusing on spatial representation of the city and public place art, and then tries to evaluate whether Busan Biennale is really embedded in the local authenticity and esthetic imagination for citizen or not. As concluding remarks, this paper suggests that Busan Biennale would be continuously developed, when it is oriented more towards local public-place art for citizens with their active participations rather than towards urban reimagineering strategy to make and promote an image of Busan as a global city.

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