• 제목/요약/키워드: Affine space

검색결과 73건 처리시간 0.02초

GENERALIZED AFFINE DEVELOPMENTS

  • Park, Joon-Sik
    • 충청수학회지
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    • 제28권1호
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    • pp.65-72
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    • 2015
  • The (affine) development of a smooth curve in a smooth manifold M with respect to an arbitrarily given affine connection in the bundle of affine frames over M is well known (cf. S.Kobayashi and K.Nomizu, Foundations of Differential Geometry, Vol.1). In this paper, we get the generalized affine development of a smooth curve $x_t$ ($t{\in}[0,1]$) in M into the affine tangent space at $x_0$ (${\in}M$) with respect to a given generalized affine connection in the bundle of affine frames over M.

FOCK SPACE REPRESENTATIONS OF QUANTUM AFFINE ALGEBRAS AND GENERALIZED LASCOUX-LECLERC-THIBON ALGORITHM

  • Kang, Seok-Jin;Kwon, Jae-Hoon
    • 대한수학회지
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    • 제45권4호
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    • pp.1135-1202
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    • 2008
  • We construct the Fock space representations of classical quantum affine algebras using combinatorics of Young walls. We also show that the crystal graphs of the Fock space representations can be realized as the crystal consisting of proper Young walls. Finally, we give a generalized version of Lascoux-Leclerc-Thibon algorithm for computing the global bases of the basic representations of classical quantum affine algebras.

INVARIANT OPEN SETS UNDER COCOMPACT AFFINE ACTIONS

  • Park, Kyeong-Su
    • 대한수학회보
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    • 제36권1호
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    • pp.203-207
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    • 1999
  • In this paper, we find a condition of an open subset of the affine space which admits a cocompact affine action. To do it, the asymptotic flag of an open convex subset is introduced and some applications to affine manifolds are presented.

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The Evaluations of Sensor Models for Push-broom Satellite Sensor

  • Lee, Suk-Kun;Chang, Hoon
    • Korean Journal of Geomatics
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    • 제4권1호
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    • pp.31-37
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    • 2004
  • The aim of this research is comparing the existing approximation models (e.g. Affine Transformation and Direct Linear Transformation) with Rational Function Model as a substitute of rigorous sensor model of linear array scanner, especially push-broom sensor. To do so, this research investigates the mathematical model of each approximation method. This is followed by the assessments of accuracy of transformation from object space to image space by using simulated data generated by collinearity equations which incorporate or depict the physical aspects of linear array sensor.

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SECOND COHOMOLOGY OF aff(1) ACTING ON n-ARY DIFFERENTIAL OPERATORS

  • Basdouri, Imed;Derbali, Ammar;Saidi, Soumaya
    • 대한수학회보
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    • 제56권1호
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    • pp.13-22
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    • 2019
  • We compute the second cohomology of the affine Lie algebra aff(1) on the dimensional real space with coefficients in the space ${\mathcal{D}}^n_{{\underline{\lambda}},{\mu}}$ of n-ary linear differential operators acting on weighted densities where ${\underline{\lambda}}=({\lambda}_1,{\ldots},{\lambda}_n)$. We explicitly give 2-cocycles spanning these cohomology.

스케일 스페이스 특징점을 이용한 영상 워터마킹 (Image Watermarking Based on Feature Points of Scale-Space Representation)

  • 서진수;유창동
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2005년도 추계종합학술대회
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    • pp.367-370
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    • 2005
  • This paper proposes a novel method for content-based watermarking based on feature points of an image. At each feature point, watermark is embedded after affine normalization according to the local characteristic scale and orientation. The characteristic scale is the scale at which the normalized scale-space representation of an image attains a maximum value, and the characteristic orientation is the angle of the principal axis of an image. By binding watermarking with the local characteristics of an image, resilience against affine transformations can be obtained. Experimental results show that the proposed method is robust against various image processing steps including affine transformations, cropping, filtering, and JPEG compression.

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어파인 불변성 사면체 분할법의 가시화 (절편 법을 이용한 사면체 구조의 가시화) (Visualization of Affine Invariant Tetrahedrization (Slice-Based Method for Visualizing the Structure of Tetrahedrization))

  • 이건
    • 한국정보처리학회논문지
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    • 제3권7호
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    • pp.1894-1905
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    • 1996
  • Dirichlet tessellation 과 쌍대관계에 있는 Delaunay triangulation은 어파인 불변성을 가지지 못한다. 즉, 삼각형 분할을 이루는데 있어서 각 꼭지점들을 나타내는 좌표축의 선택에 영향을 받는다. 같은 이유로 Delaunay triangulation (사면체 분할법) 도 어파인 불변성을 가지지 못한다. 본 논문에서는 공간상 점들로 사면체 분할하는데 있어서 변환, 확대 축소, 일그러뜨림, 회전에도 여향을 받지 않는 새로운 유형의 사면체 분할 방법을 제시하였다. 어파인 사면체 분할을 논의 할 때 기존의 어파인 불변성 평면적 삼각형 분할을 삼차원 분할을 삼차원적 사면체 분할로 연장시키는 방법을 사용 하였다. 삼차원 공간상의 두 점간의 거리를 새롭게 정의 하였다. 사면체 구조의 가시 화를 통하여 Delaunay 사면체 분할과 어파인 불변성 사면체 분하라 결과를 구별시 킬 수 있었다.

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DEFORMATION SPACES OF CONVEX REAL-PROJECTIVE STRUCTURES AND HYPERBOLIC AFFINE STRUCTURES

  • Darvishzadeh, Mehdi-Reza;William M.Goldman
    • 대한수학회지
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    • 제33권3호
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    • pp.625-639
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    • 1996
  • A convex $RP^n$-structure on a smooth anifold M is a representation of M as a quotient of a convex domain $\Omega \subset RP^n$ by a discrete group $\Gamma$ of collineations of $RP^n$ acting properly on $\Omega$. When M is a closed surface of genus g > 1, then the equivalence classes of such structures form a moduli space $B(M)$ homeomorphic to an open cell of dimension 16(g-1) (Goldman [2]). This cell contains the Teichmuller space $T(M)$ of M and it is of interest to know what of the rich geometric structure extends to $B(M)$. In [3], a symplectic structure on $B(M)$ is defined, which extends the symplectic structure on $T(M)$ defined by the Weil-Petersson Kahler form.

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