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231.
Julie Clutterbuck Oliver C. Schnürer Felix Schulze 《Calculus of Variations and Partial Differential Equations》2007,29(3):281-293
We prove stability of rotationally symmetric translating solutions to mean curvature flow. For initial data that converge
spatially at infinity to such a soliton, we obtain convergence for large times to that soliton without imposing any decay
rates.
The authors are members of SFB 647/B3 “Raum – Zeit – Materie: Singularity Structure, Long-time Behaviour and Dynamics of Solutions
of Non-linear Evolution Equations”. 相似文献
232.
Yasunari Nagai 《manuscripta mathematica》2003,110(3):273-282
We give a characterization of irreducible symplectic fourfolds which are given as Hilbert scheme of points on a K3 surface.
Received: 26 June 2002 / Revised version: 9 September 2002 Published online: 14 February 2003
Mathematics Subject Classification (2000): Primary 14J32, Secondary 32Q20 相似文献
233.
Serge Tabachnikov 《Geometriae Dedicata》2007,129(1):83-87
We prove a recent theorem by C. Culter every polygonal outer billiard in the affine plane has a periodic trajectory.
相似文献
234.
Most of the few known examples of compact Riemannian manifolds with positive sectional curvature are the total space of a
Riemannian submersion. In this article we show that this is true for all known examples, if we enlarge the category to orbifold
fibrations. For this purpose we study all almost free isometric circle actions on positively curved Eschenburg spaces, which
give rise to principle orbifold bundle structures, and we examine in detail their geometric properties. In particular, we
obtain a new family of 6-dimensional orbifolds with positive sectional curvature whose singular locus consists of just two
points.
相似文献
235.
The paper proves the existence of solutions to the magneto-hydrodynamics equations driven by random exterior forcing terms
both in the velocity and in the magnetic field. The existence and uniqueness of an invariant measure is also obtained via
coupling methods. 相似文献
236.
237.
238.
Background
Repeated execution of a tactile task enhances task performance. In the present study we sought to improve tactile performance with unattended activation-based learning processes (i.e., focused stimulation of dermal receptors evoking neural coactivation (CA)). Previous studies show that the application of CA to a single finger reduced the stationary two-point discrimination threshold and significantly increased tactile acuity. These changes were accompanied by an expansion of the cortical finger representation in primary somatosensory cortex (SI). Here we investigated the effect of different types of multifinger CA on the tactile performance of each finger of the right hand. 相似文献239.
Friedrich Leisch 《Computational Statistics》2007,22(4):555-555
240.
Transfer matrix approach of vibration isolation analysis of periodic composite structure 总被引:1,自引:0,他引:1
Wang Yong Huang Qibai Zhou Minggang Xu Zhisheng 《Archive of Applied Mechanics (Ingenieur Archiv)》2007,77(7):461-471
The transmission properties of elastic waves propagating in a three-dimensional composite structure embedded periodically
with spherical inclusions are analyzed by the transfer matrix method in this paper. Firstly, the periodic composite structures
are divided into many layers, the transfer matrix of monolayer structure is deduced by the wave equations, and the transfer
matrix of the entire structure is obtained in the case of boundary conditions of displacement and stress continuity between
layers. Then, the effective impedance of the structure is analyzed to calculate its reflectivity and transmissivity of vibration
isolation. Finally, numerical simulation is carried out; the experiment results validate the accuracy and feasibility of the
method adopted in the paper and some useful conclusions are obtained.
Project (No. 50075029) supported by the National Natural Science Foundation of China. 相似文献