• 제목/요약/키워드: minimal surfaces

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INVOLUTIONS ON SURFACES OF GENERAL TYPE WITH pg = 0 I. THE COMPOSED CASE

  • Shin, YongJoo
    • 대한수학회논문집
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    • 제28권3호
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    • pp.425-432
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    • 2013
  • Let S be a minimal surface of general type with $p_g(S)=q(S)=0$ having an involution ${\sigma}$ over the field of complex numbers. It is well known that if the bicanonical map ${\varphi}$ of S is composed with ${\sigma}$, then the minimal resolution W of the quotient $S/{\sigma}$ is rational or birational to an Enriques surface. In this paper we prove that the surface W of S with $K^2_S=5,6,7,8$ having an involution ${\sigma}$ with which the bicanonical map ${\varphi}$ of S is composed is rational. This result applies in part to surfaces S with $K^2_S=5$ for which ${\varphi}$ has degree 4 and is composed with an involution ${\sigma}$. Also we list the examples available in the literature for the given $K^2_S$ and the degree of ${\varphi}$.

삼중 주기적 최소곡면을 이용한 조직공학을 위한 생체모사 스캐폴드의 컴퓨터응용 설계 및 제작 (Computer-aided Design and Fabrication of Bio-mimetic Scaffold for Tissue Engineering Using the Triply Periodic Minimal Surface)

  • 유동진
    • 한국정밀공학회지
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    • 제28권7호
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    • pp.834-850
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    • 2011
  • In this paper, a novel tissue engineering scaffold design method based on triply periodic minimal surface (TPMS) is proposed. After generating the hexahedral elements for a 3D anatomical shape using the distance field algorithm, the unit cell libraries composed of triply periodic minimal surfaces are mapped into the subdivided hexahedral elements using the shape function widely used in the finite element method. In addition, a heterogeneous implicit solid representation method is introduced to design a 3D (Three-dimensional) bio-mimetic scaffold for tissue engineering from a sequence of computed tomography (CT) medical image data. CT image of a human spine bone is used as the case study for designing a 3D bio-mimetic scaffold model from CT image data.

COMPLETE MAXIMAL SPACE-LIKE HYPERSURFACES IN AN ANTI-DE SITTER SPACE

  • Choi, Soon-Meen;Ki, U-Hang;Kim, He-Jin
    • 대한수학회보
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    • 제31권1호
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    • pp.85-92
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    • 1994
  • It is well known that there exist no closed minimal surfaces in a 3-dimensional Euclidean space R$^{3}$. Myers [4] generalized the result to the case of the higher dimension and proved that there are no closed minimal hypersurfaces in an open hemisphere. The complete and non-compact version concerning Myers' theorem is recently considered by Cheng [1] and the following theorem is proved.

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Lower Bounds on Boundary Slope Diameters for Montesinos Knots

  • Ichihara, Kazuhiro;Mizushima, Shigeru
    • Kyungpook Mathematical Journal
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    • 제49권2호
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    • pp.321-348
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    • 2009
  • In this paper, we give two lower bounds on the diameter of the boundary slope set of a Montesinos knot. One is described in terms of the minimal crossing numbers of the knots, and the other is related to the Euler characteristics of essential surfaces with the maximal/minimal boundary slopes.

CONSTANT CURVATURES AND SURFACES OF REVOLUTION IN L3

  • Kang, Ju-Yeon;Kim, Seon-Bu
    • 호남수학학술지
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    • 제38권1호
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    • pp.151-167
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    • 2016
  • In Minkowskian 3-spacetime $L^3$ we find timelike or spacelike surface of revolution for the given Gauss curvature K = -1, 0, 1 and mean curvature H = 0. In fact, we set up the surface of revolution with the time axis for z-axis to be able to draw those surfaces on standard pictures in Minkowskian 3-spacetime $L^3$.

SPHERICAL SUBMANIFOLDS WITH FINITE TYPE SPHERICAL GAUSS MAP

  • Chen, Bang-Yen;Lue, Huei-Shyong
    • 대한수학회지
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    • 제44권2호
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    • pp.407-442
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    • 2007
  • The study of Euclidean submanifolds with finite type "classical" Gauss map was initiated by B.-Y. Chen and P. Piccinni in [11]. On the other hand, it was believed that for spherical sub manifolds the concept of spherical Gauss map is more relevant than the classical one (see [20]). Thus the purpose of this article is to initiate the study of spherical submanifolds with finite type spherical Gauss map. We obtain several fundamental results in this respect. In particular, spherical submanifolds with 1-type spherical Gauss map are classified. From which we conclude that all isoparametric hypersurfaces of $S^{n+1}$ have 1-type spherical Gauss map. Among others, we also prove that Veronese surface and equilateral minimal torus are the only minimal spherical surfaces with 2-type spherical Gauss map.

INVARIANTS OF DEFORMATIONS OF QUOTIENT SURFACE SINGULARITIES

  • Han, Byoungcheon;Jeon, Jaekwan;Shin, Dongsoo
    • 대한수학회지
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    • 제56권5호
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    • pp.1173-1246
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    • 2019
  • We find all P-resolutions of quotient surface singularities (especially, tetrahedral, octahedral, and icosahedral singularities) together with their dual graphs, which reproduces (a corrected version of) Jan Steven's list [Manuscripta Math. 1993] of the numbers of P-resolutions of each singularities. We then compute the dimensions and Milnor numbers of the corresponding irreducible components of the reduced base spaces of versal deformations of each singularities. Furthermore we realize Milnor fibers as complements of certain divisors (depending only on the singularities) in rational surfaces via the semi-stable minimal model program for 3-folds. Then we compare Milnor fibers with minimal symplectic fillings, where the latter are classified by Bhupal and Ono [Nagoya Math. J. 2012]. As an application, we show that there are 6 pairs of entries in the list of Bhupal and Ono [Nagoya Math. J. 2012] such that two entries in each pairs represent diffeomorphic minimal symplectic fillings.

SYMMETRY AND UNIQUENESS OF EMBEDDED MINIMAL HYPERSURFACES IN ℝn+1

  • Park, Sung-Ho
    • 대한수학회보
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    • 제58권1호
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    • pp.21-30
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    • 2021
  • In this paper, we prove some rigidity results about embedded minimal hypersurface M ⊂ ℝn+1 with compact ∂M that has one end which is regular at infinity. We first show that if M ⊂ ℝn+1 meets a hyperplane in a constant angle ≥ ��/2, then M is part of an n-dimensional catenoid. We show that if M meets a sphere in a constant angle and ∂M lies in a hemisphere determined by the hyperplane through the center of the sphere and perpendicular to the limit normal vector nM of the end, then M is part of either a hyperplane or an n-dimensional catenoid. We also show that if M is tangent to a C2 convex hypersurface S, which is symmetric about a hyperplane P and nM is parallel to P, then M is also symmetric about P. In special, if S is rotationally symmetric about the xn+1-axis and nM = en+1, then M is also rotationally symmetric about the xn+1-axis.