Contraction Flow by Certain Curvature of Convex Hypersurfaces

In the following mixed tensors on the hypersurface M Rn+1 under consideration willbe denoted by T={ Tijkl} ,the induced metric by g={ gij} and the second fundamentalform by A={ hij} .We always sum overrepeated indices from1 to n and use brackets forthe inner product on M:〈Tijk,Sijk〉 =gisgjαgkβTijk Ssαβ,　 | T| 2 =〈Tijk,Tijk〉.Setrkl =gkαhαl,Sm(λ1 ,… ,λn) = i1<… 相似文献   

Almost Spherical Convex Hypersurfaces in R4

It is shown that if a ratio of two mean curvature functions of a closed convex hypersurface in the four-dimensional Euclidean space is sufficiently close to a constant, then the hypersurface lies between two concentric round spheres of sufficiently close radii.     

Inverse Anisotropic Curvature Flow from Convex Hypersurfaces

In this paper, we study the inverse anisotropic curvature flow from strictly convex hypersurfaces. We show the long-time existence and the convergence to the Wulff shape after rescaling, under certain conditions on the general speed functions.     

由曲率函数和外力场之差支配的凸超曲面的发展

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Comparison Theorems on Convex Hypersurfaces in Hadamard Manifolds

In a Hadamard manifold with sectional curvaturebounded from below by –k ₂ ², we give sharp upper estimates for the difference circumradius minus inradiusof a compact k ₂-convex domain, and we getalso estimates for the quotient (Total d-mean curvature)/Area of a convex domain.     

Focal Loci of Algebraic Hypersurfaces: A General Theory

The focal locus is traditionally defined for a differentiable submanifold of R ⁿ. However, since it depends essentially only on the notion of orthogonality, a focal locus can be also associated to an algebraic subvariety of the space , once we have chosen an orthogonal structure on this space. In this paper, we establish somebasic results in the theory of focal loci of algebraichypersurfaces in . Our main results concern the irreducibility of the ramification divisor of the end-point map and the dimension of the singular locus of this divisor, the birationality of the focal map and the degree of the focal locus of an algebraic hypersurface.     

Curvature Flow of Complete Convex Hypersurfaces in Hyperbolic Space

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Starshaped Locally Convex Hypersurfaces with Prescribed Curvature and Boundary

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Shape Preserving Interpolation to Convex Data

1.IntroductionA fundamental problem in computer graphics is the drawing of a smooth curve through aset of data points(xi,fi) (i=0 ,1 ,… ,n) .In many applications,particularly in scientificvisualisation,the y- values are depenenton the x- values and it is…     

Convex Hypersurfaces with Prescribed Curvature and Boundary in Riemannian Manifolds

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Shape Preserving Interpolation to Convex Data by Rational Functions with Quadratic Numerator and Linear Denominator

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