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61.
Cesàro (C,δ) means are studied for orthogonal expansions with respect to the weight function
on the unit sphere, and for the corresponding weight functions on the unit ball and the Jacobi weight on the simplex. A sharp
pointwise estimate is established for the (C,δ) kernel with δ>−1 and for the kernel of the projection operator, which allows us to derive the exact order for the norm of the Cesàro means
and the projection operator on these domains.
相似文献
62.
Qiaoling Wang 《Journal of Mathematical Analysis and Applications》2010,364(1):1-17
In this paper, we study the eigenvalues of the clamped plate problem:
63.
A fractional-order Qi four-wing chaotic system is present based on the Grunwald-Letnikov denition. The existence of topological horseshoe in a fractional chaotic system is analyzed by utilizing topological horseshoe theory. A Poincare section is properly chosen to obtain the Poincare map which is proved to be semi-conjugate to a 2-shift map, implying that the fractional-order Qi four-wing chaotic system exhibits chaos. 相似文献
64.
王玉玉 《数学年刊A辑(中文版)》2018,39(3):273-286
本文中,通过几何方法证明了σ相关同伦元素在球面稳定同伦群π_mS中是非平凡的,其中m=p~(n+1)q+2p~nq+(s+3)p~2q+(s+3)pq+(s+3)q-8,p≥7是奇素数,n3,0≤sp-3,且q=2(p-1).该σ相关同伦元素在Adams谱序列的E_2-项中由■_s+3■_ng0表示. 相似文献
65.
Xiaoli Chao Ranran Chen 《逼近论及其应用》2008,(3):292-302
We discuss a class of complete Kaihler manifolds which are asymptotically complex hyperbolic near infinity. The main result is vanishing theorems for the second L2 cohomology of such manifolds when it has positive spectrum. We also generalize the result to the weighted Poincare inequality case and establish a vanishing theorem provided that the weighted function p is of sub-quadratic growth of the distance function. We also obtain a vanishing theorem of harmonic maps on manifolds which satisfies the weighted Poincare inequality. 相似文献
66.
Poincaré线性连续统直觉概念的公式化(英文) 总被引:1,自引:1,他引:0
本文研究了Poincaré著名注记中“内束”观念的数学表述法问题,通过构建Poincaré连续统模型,得到了这一问题的一种解答。文中还论述了有关数理哲学及方法论问题;文末特别指出了须继续研究的数学问题。 相似文献
67.
Synthesis of Nanometer-sized Mesoporous Oxide Spheres 总被引:1,自引:0,他引:1
IntroductionMesoporous materials have been used as versatile catalysts, catalyst supports, host forclusters, and applied to normal phase chromatography, and they are potentially applicable for...sensor arrays, m1nlaturized electronic and magnetic device.[l--6]. More recently the meso-porous silicas with morphologies including thin films, monoliths and hexagonal prisms,toroidal, disk-like, spiral and hollow tubular shapes have been synthesized['--1'1. In addition,mesoporous silica spheres of de… 相似文献
68.
Pankaj Agarwal Leonidas Guibas An Nguyen Daniel Russel Li Zhang 《Computational Geometry》2004,28(2-3):137-SoCG2002
In this paper, we propose to study deformable necklaces—flexible chains of balls, called beads, in which only adjacent balls may intersect. Such objects can be used to model macro-molecules, muscles, ropes, and other linear objects in the physical world. We exploit this linearity to develop geometric structures associated with necklaces that are useful for collision detection in physical simulations. We show how these structures can be implemented efficiently and maintained under necklace deformation. In particular, we study a bounding volume hierarchy based on spheres which can be used for collision and self-collision detection of deforming and moving necklaces. As our theoretical and experimental results show, such a hierarchy is easy to compute and, more importantly, is also easy to maintain when the necklace deforms. Using this hierarchy, we achieve a collision detection upper bound of O(nlogn) in two dimensions and O(n2−2/d) in d-dimensions, d3. To our knowledge, this is the first subquadratic bound proved for a collision detection algorithm using predefined hierarchies. In addition, we show that the power diagram, with the help of some additional mechanisms, can be used to detect self-collisions of a necklace in a way that is complementary to the sphere hierarchy. 相似文献
69.
Marco Castrillón López Jerrold E. Marsden 《Annals of Global Analysis and Geometry》2008,34(3):263-285
Reduction for field theories with symmetry can be done either covariantly—that is, on spacetime—or dynamically—that is, after
spacetime is split into space and time. The purpose of this article is to show that these two reduction procedures are, in
an appropriate sense, equivalent for a class of field theories whose fields take values in a principal bundle. One can think
of this class of field theories as including examples such as a “sea of rigid bodies” with and appropriate interbody coupling
potential. 相似文献
70.
单位球面的三维紧致极小子流形 总被引:3,自引:0,他引:3
本文得到高维球面上三维紧致极小子流形的若干刚性定理.在一个整体拚挤条件下,数量曲率的拚挤常数被改进了,也对李奇曲率的拚挤问题进行了讨论. 相似文献