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101.
102.
双三次Bezier曲面片的光滑拼接 总被引:5,自引:3,他引:2
本文根据曲面的总曲率和平均曲率推导出双三次Bezier曲面片拼接的C^2连续条件。 相似文献
103.
Akhil Ranjan 《Proceedings Mathematical Sciences》2000,110(1):27-34
In this paper we give a proof of Lichnerowicz conjecture for compact simply connected manifolds which is intrinsic in the
sense that it avoids thenice embeddings into eigenspaces of the Laplacian. Even if one wants to use these embeddings, this paper gives a more streamlined proof.
As a byproduct, we get a simple criterion for a polynomial to be a Jacobi polynomial. 相似文献
104.
Valery Marenich 《Transactions of the American Mathematical Society》2000,352(10):4451-4468
We prove that a convergence in the Gromov-Hausdorff distance of manifolds with minimal radial curvature bounded from below by 1 to the standard sphere is equivalent to a volume convergence.
105.
In this paper, an adaptive nonmonotone line search method for unconstrained minimization problems is proposed. At every iteration,
the new algorithm selects only one of the two directions: a Newton-type direction and a negative curvature direction, to perform
the line search. The nonmonotone technique is included in the backtracking line search when the Newton-type direction is the
search direction. Furthermore, if the negative curvature direction is the search direction, we increase the steplength under
certain conditions. The global convergence to a stationary point with second-order optimality conditions is established. Some
numerical results which show the efficiency of the new algorithm are reported.
相似文献
106.
Given a positive function F on S^n which satisfies a convexity condition, we introduce the r-th anisotropic mean curvature Mr for hypersurfaces in R^n+1 which is a generalization of the usual r-th mean curvature Hr. We get integral formulas of Minkowski type for compact hypersurfaces in R^n+1. We give some new characterizations of the Wulff shape by the use of our integral formulas of Minkowski type, in case F=1 which reduces to some well-known results. 相似文献
107.
We prove the existence of a geometric characteristic submanifold for non-positively curved manifolds of any dimension greater
than or equal to three. In dimension three, our result is a geometric version of the topological characteristic submanifold
theorem due to Jaco, Shalen and Johannson.
Received: May 20, 1996 相似文献
108.
The purpose of this note is to exhibit some simple and basic constructions for smooth compact transformation groups, and some of their most immediate applications to geometry. 相似文献
109.
Maria Fernanda Elbert 《Proceedings of the American Mathematical Society》2000,128(5):1443-1450
We generalize Efimov's Theorem for graphs in Euclidean space using the scalar curvature, with an additional hypothesis on the second fundamental form. 相似文献
110.
Based on the linear viscoelastic differential constitutive law and cable structural model, the coupled longitudinal-transverse
waves that propagate along a viscoelastic cable with small curvature is investigated. A mathematical model is presented that
describes the three-dimensional nonlinear response of a viscoelastic cable. An asymptotic form of this model is obtained for
the linear response of cables having small equilibrium curvature. The spectral relation governing the propagating waves is
derived using transform methods. The spectral relation is employed in deriving a Green's function that is then used to construct
solutions for in-plane response under distributed harmonic excitation. Analysis of forced response reveals the existence of
two types of periodic waves that propagate through the cable, one characterizing extension-comprehensive deformation and the
other characteristic transverse deformation.
Project supported by the National Natural Science Foundation of China (No. 59635140). 相似文献