• 제목/요약/키워드: Vanishing

검색결과 375건 처리시간 0.024초

LOCALLY PRODUCT INDEFINITE KAEHLERIAN METRICS WITH VANISHING CONFORMAL CURVATURE TENSOR FIELD

  • Kwon, Jung-Hwan;Sohn, Won-Ho
    • 대한수학회보
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    • 제29권1호
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    • pp.25-29
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    • 1992
  • The purpose of this paper is to study indefinite Kaehlerian metrics with vanishing conformal curvature tensor field. In the first section, a brief summary of the complex version of indefinite Kaehlerian manifolds is recalled and we introduce the conformal curvature tensor field on an indefinite Kaehlerian manifold. In section 2, we obtain the theorem for indefinite Kaehlerian metrics with vanishing conformal curvature tensor field.

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도로영상에서 허프변환과 무한원점을 이용한 카메라 위치 및 자세 추정 알고리즘 (The estimation of camera's position and orientation using Hough Transform and Vanishing Point in the road Image)

  • 채정수;최성구;노도환
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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    • pp.511-513
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    • 2004
  • Camera Calibration should certain)y be achieved to take an accurate measurement using image system. Calibration is to prove the relation between an measurement object and camera and to estimate twelve internal and external parameters. In this paper, we suggest that an algorithm should estimate the external parameters from the road image and use a vanishing point's character from parallel straight lines in a space. also, we use Hough Transform to estimate an accurate vanishing point. Hough Transform has one of the advantages which is an application for each road environment. we assume a variety of environments to prove the usability of a suggested algorithm and show simulation results with a computer.

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DNN과 HoG Feature를 이용한 도로 소실점 검출 방법 (Method for Road Vanishing Point Detection Using DNN and Hog Feature)

  • 윤대은;최형일
    • 한국콘텐츠학회논문지
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    • 제19권1호
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    • pp.125-131
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    • 2019
  • 소실점이란 실제 공간의 평행한 선들이 영상 내에 투영되면서 한곳에 모이는 점으로, 도로 공간에서의 소실점은 매우 중요한 공간정보이다. 도로 공간에서의 소실점을 이용해 추출된 차선의 위치를 개선하거나, 깊이지도 영상을 생성할 수 있다. 본 논문에서는 자동차의 시점을 기준으로 도로를 촬영한 영상을 Deep Neural Network(DNN)과 Histogram of Oriented Gradient(HoG) Feature를 이용한 소실점 검출 방법을 제안한다. 제안하는 알고리즘에서는 영상을 블록별로 나눠서 주요 에지 방향을 추출하는 HoG Feature 추출 단계와 DNN 학습 단계, 그리고 Test 단계로 나뉜다. 학습단계에서는 자동차 시점으로 기준으로 도로 영상 2300장으로 학습을 진행한다. 그리고 Test 단계에서는 Normalized Euclidean Distance(NormDist) 방법을 사용하여 제안하는 알고리즘의 효율성을 측정한다.

수학자 테일러의 선 원근법과 화가 커비의 해설서 (Mathematician Taylor's Linear Perspective Theory and Painter Kirby's Handbook)

  • 조은정
    • 미술이론과 현장
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    • 제7호
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    • pp.165-188
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    • 2009
  • In the development of linear perspective, Brook Taylor's theory has achieved a special position. With his method described in Linear Perspective(1715) and New Principles of Linear Perspective(1719), the subject of linear perspective became a generalized and abstract theory rather than a practical method for painters. He is known to be the first who used the term 'vanishing point'. Although a similar concept has been used form the early stage of Renaissance linear perspective, he developed a new method of British perspective technique of measure points based on the concept of 'vanishing points'. In the 15th and 16th century linear perspective, pictorial space is considered as independent space detached from the outer world. Albertian method of linear perspective is to construct a pavement on the picture in accordance with the centric point where the centric ray of the visual pyramid strikes the picture plane. Comparison to this traditional method, Taylor established the concent of a vanishing point (and a vanishing line), namely, the point (and the line) where a line (and a plane) through the eye point parallel to the considered line (and the plane) meets the picture plane. In the traditional situation like in Albertian method, the picture plane was assumed to be vertical and the center of the picture usually corresponded with the vanishing point. On the other hand, Taylor emphasized the role of vanishing points, and as a result, his method entered the domain of projective geometry rather than Euclidean geometry. For Taylor's theory was highly abstract and difficult to apply for the practitioners, there appeared many perspective treatises based on his theory in England since 1740s. Joshua Kirby's Dr. Brook Taylor's Method of Perspective Made Easy, Both in Theory and Practice(1754) was one of the most popular treatises among these posterior writings. As a well-known painter of the 18th century English society and perspective professor of the St. Martin's Lane Academy, Kirby tried to bridge the gap between the practice of the artists and the mathematical theory of Taylor. Trying to ease the common readers into Taylor's method, Kirby somehow abbreviated and even omitted several crucial parts of Taylor's ideas, especially concerning to the inverse problems of perspective projection. Taylor's theory and Kirby's handbook reveal us that the development of linear perspective in European society entered a transitional phase in the 18th century. In the European tradition, linear perspective means a representational system to indicated the three-dimensional nature of space and the image of objects on the two-dimensional surface, using the central projection method. However, Taylor and following scholars converted linear perspective as a complete mathematical and abstract theory. Such a development was also due to concern and interest of contemporary artists toward new visions of infinite space and kaleidoscopic phenomena of visual perception.

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VANISHING THEOREM ON SINGULAR MODULI SPACES

  • Cho, Yong-Seung;Hong, Yoon-Hi
    • 대한수학회지
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    • 제33권4호
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    • pp.1069-1099
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    • 1996
  • Let X be a smooth, simply connected and oriented closed fourmanifold such that the dimension $b_{2}^{+}(X)$ of a maximal positive subspace for the intersection form is greater than or equal to 3.

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