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991.
It has been proved that if a rectangle is dissected into three congruent pieces,then those pieces must themselves be rectangles. In the present paper this result is generalized to the case of parallelogram. 相似文献
992.
Wei-Yue Ding 《manuscripta mathematica》1994,85(1):283-297
By introducing the “relative energy”, we develop a new method for finding harmonic maps from noncompact complete Riemannian manifolds with prescribed asympototic behaviour at infinity. This method is an extension of the well known direct method of energy-minimization for compact domains. As an application of our method, we show that the Dirichlet problem at infinity with Hölder continuous boundary data for harmonic maps from a Cartan-Hadarmard manifold with bounded negative curvature into a compact manifold, has a locally minimizing solution which is smooth near infinity. 相似文献
993.
Yu Ding Ruggero Micheletto Hiroaki Hanada Toshihiko Nagamura Satoshi Okazaki Koji Otsuka 《Optical Review》2002,9(6):277-281
This work describes a groundbreaking process that provides a direct highly localized measurement of the atomic mass on surfaces at room temperature. Employing an original system that joins a scanning tunneling microscopy (STM) device and a time of flight (TOF) mass analyzer, we could previously ionize surface atoms by the combination of an optical laser pulse and an electric pulse at the STM tip. Desorbed ions from a localized area were accelerated and detected by a TOF chamber. We will demonstrate in this paper that high localization and mass discrimination can be obtained even without the aid of an electric pulse from the tip. We reduced the angle of incidence of the laser beam to zero (laser beam parallel to the sample surface). In this condition we were able to demonstrate for the first time ionic desorption at a confinement level of the order of 5-10nm, an order of magnitude better than previous configurations.This paper was originally presented at the 11th Optical Near Field Workshop, which was held on June 28, 2002 at Tokyo Institute of Technology, Yokohama, organized by the Optical Near Field Group of the Optical Society of Japan, an affiliate of the Japan Society of Applied Physics. 相似文献
994.
Using the theory of random closed sets, we extend the statistical framework introduced by Schreiber(11) for inference based on set-valued observations from the case of finite sample spaces to compact metric spaces with continuous distributions. 相似文献
995.
996.
M. L. Li S. J. Zhu S. D. Xiao X. L. Che Y. N. U Y. J. Chen H. B. Ding L. H. Zhu G. S. Li S. X. Wen X. G. Wu 《The European Physical Journal A - Hadrons and Nuclei》2006,28(1):1-4
High-spin states of 137La have been investigated with the reaction 130Te(11B, 4n) at a beam energy of 50MeV. The level scheme of 137La has been expanded with spin up to 33/2ℏ. Several new bands have been found in this nucleus. A band crossing in the band
based on the 17/2- level has been observed at a rotational frequency of ℏω ∼ 0.48MeV. From systematic comparison, this band crossing probably
originates from the alignment of protons. One of the bands with strong M1 transitions is proposed as a collective oblate band ( γ ∼ -60°). 相似文献
997.
The 1-Lipschitz mapping between the unit spheres of two Hilbert spaces can be extended to a real linear isometry of the whole space 总被引:18,自引:0,他引:18
定光桂 《中国科学A辑(英文版)》2002,45(4):479-483
LetE andF be Hilbert spaces with unit spheresS
1(E) andS
1(F). Suppose thatV
0 S1(E) →S
1(F) is a Lipschitz mapping with Lipschitz constantk=1 such that −V
0[S
1(E)] ⊂V
0[S
1(E)]. Then V0 can be extended to a real linear isometric mappingV fromE intoF. In particular, every isometric mapping fromS
1(E) ontoS
1(F) can be extended to a real linear isometric mapping fromE ontoF. 相似文献
998.
On strictly separating vectors and reflexivity 总被引:5,自引:0,他引:5
Lifeng Ding 《Integral Equations and Operator Theory》1994,19(4):373-380
It is shown that the set of strongly disjoint pairs of strictly separating vectors for an operator space is open, and an operator subspace having a strongly disjoint pair of strictly separating vectors is reflexive. Some applications are discussed. 相似文献
999.
本文讨论的两个时偶问题涉及来一个泊松过程与一个更新过程穿越时间和更新数的联合分布.利用向量马氏过程方法得到了这些联合分布的变换,给出了一个与分布均值有关量的数值结果. 相似文献
1000.
在FC-空间中证明了一新的非空交定理.作为应用,一不动点定理,一极大元定理,一重合点定理和一些极小极大不等式被证明.这些定理推广了近期文献中的结果. 相似文献