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101.
逆极限的不变测度和一致正熵性质 总被引:2,自引:0,他引:2
In this paper, the interconnection of some ergodic properties between a continuous selfmap and its inverse limit is studied. It has been proved that (1) their invariant Borel probability measures are identical up to homeomorphism and (2) they preserve uniform positive entropy property simuitaneously. As applications, it is also proved that the upper semi-continu-ous properties of their entropy maps are restricted each other, and the entropy map of the asymptotically h-expansive continuous map is upper semi-contlnuous, at the same time a continuous map having u, p.e. is topological weakmixing. 相似文献
102.
Piotr Kicinski 《Proceedings of the American Mathematical Society》1999,127(3):783-789
It is shown that polarization formulas have explicit matrix representations. This enables us to prove that polarization formulas of -positive maps between -algebras are coordinatewise positive.
103.
Naoya Sumi 《Proceedings of the American Mathematical Society》1999,127(3):915-924
We show that on the 2-torus there exists a open set of regular maps such that every map belonging to is topologically mixing but is not Anosov. It was shown by Mañé that this property fails for the class of toral diffeomorphisms, but that the property does hold for the class of diffeomorphisms on the 3-torus . Recently Bonatti and Diaz proved that the second result of Mañé is also true for the class of diffeomorphisms on the -torus ().
104.
Given a continuous P0-function F : Rn Rn, we describe a method of constructing trajectories associated with the P0-equation F(x) = 0. Various well known equation-based reformulations of the nonlinear complementarity problem and the box variational inequality problem corresponding to a continuous P0-function lead to P0-equations. In particular, reformulations via (a) the Fischer function for the NCP, (b) the min function for the NCP, (c) the fixed point map for a BVI, and (d) the normal map for a BVI give raise to P0-equations when the underlying function is P0. To generate the trajectories, we perturb the given P0-function F to a P-function F(x, ); unique solutions of F(x, ) = 0 as varies over an interval in (0, ) then define the trajectory. We prove general results on the existence and limiting behavior of such trajectories. As special cases we study the interior point trajectory, trajectories based on the fixed point map of a BVI, trajectories based on the normal map of a BVI, and a trajectory based on the aggregate function of a vertical nonlinear complementarity problem. 相似文献
105.
Bernard Coupet Hervé Gaussier Alexandre Sukhov 《Proceedings of the American Mathematical Society》1999,127(11):3191-3200
We study rigidity and regularity properties of CR maps between smooth convex hypersurfaces of finite type in
106.
区间上平顶单峰扩张自映射的周期轨道 总被引:2,自引:0,他引:2
设t(0<t<1)是一个常数,n≥3是奇数,m≥0及k≥1是整数,P0(x)=x-1,Pi(x)=(x2i-1-1)Pi-1(x)(i≥1),rmn(t)及rk(t)分别是方程Pm(x)(x2mn-2x2m(n-2)-1)-t(x2mn-1)(x2m+1)=0及Pk-1(x)-t(x2k-1+1)=0在(1,+∞)上的唯一实根,f是闭区间I=[0,1]上的峰顶区间长度为t的平顶单峰扩张自映射.本文证明了,若f的扩张常数λ≥rmn(t)(或>rk(t)),,则f有2mn(或2k)周期点.此外,本文还指出,当1<λ<rmn(t)(或≤rk(t)时,在I上存在着具有扩张常数λ及峰顶区间长度t却无2mn(或2k)周期点的平顶单峰扩张自映射 相似文献
107.
本文对高阶奇性常微分方程的非退化边值问题建立了非共轭性存在定理和上、下解型存在定理. 相似文献
108.
本文通过建立复Grassmann流形G2,n中调和曲面的Gauss丛的基本公式,在适当的拓扑条件下给出了G2,n中可兼共形调和曲面的构造定理.推广和改进了Burstall和Wood的低亏格曲面的结果. 相似文献
109.
Affine-Invariant Distances, Envelopes and Symmetry Sets 总被引:3,自引:0,他引:3
Affine invariant symmetry sets of planar curves are introduced and studied in this paper. Two different approaches are investigated. The first one is based on affine invariant distances, and defines the symmetry set as the closure of the locus of points on (at least) two affine normals and affine-equidistant from the corresponding points on the curve. The second approach is based on affine bitangent conics. In this case the symmetry set is defined as the closure of the locus of centers of conics with (at least) 3-point contact with the curve at two or more distinct points on the curve. This is equivalent to conic and curve having, at those points, the same affine tangent, or the same Euclidean tangent and curvature. Although the two analogous definitions for the classical Euclidean symmetry set are equivalent, this is not the case for the affine group. We present a number of properties of both affine symmetry sets, showing their similarities with and differences from the Euclidean case. We conclude the paper with a discussion of possible extensions to higher dimensions and other transformation groups, as well as to invariant Voronoi diagrams. 相似文献
110.
CompletelyPositiveDefiniteMapsOverTopological-algebrasXuTianzhou(DepartmentofAppliedMathematics,BeijingInstituteofTechnofogy,... 相似文献