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901.
F.T. Yuan S.K. Chen W.M. Liao C.W. Hsu S.N. Hsiao W.C. Chang 《Journal of magnetism and magnetic materials》2006
The Au/FePt samples were prepared by depositing a gold cap layer at room temperature onto a fully ordered FePt layer, followed by an annealing at 800 °C for the purpose of interlayer diffusion. After the deposition of the gold layer and the high-temperature annealing, the gold atoms do not dissolve into the FePt Ll0 lattice. Compared with the continuous FePt film, the TEM photos of the bilayer Au(60 nm)/FePt(60 nm) show a granular structure with FePt particles embedded in Au matrix. The coercivity of Au(60 nm)/FePt(60 nm) sample is 23.5 kOe, which is 85% larger than that of the FePt film without Au top layer. The enhancement in coercivity can be attributed to the formation of isolated structure of FePt ordered phase. 相似文献
902.
Xia Chen 《Journal of Theoretical Probability》2006,19(3):721-739
We establish moderate and small deviations for the ranges of integer valued random walks. Our theorems apply to the limsup
and the liminf laws of the iterated logarithm.
We establish moderate and small deviations for the ranges of integer valued random walks. Our theorems apply to the limsup
and the liminf laws of the iterated logarithm. 相似文献
903.
904.
Rhyd Lewis 《Journal of Heuristics》2007,13(4):387-401
In this paper we present, to our knowledge, the first application of a metaheuristic technique to the very popular and NP-complete
puzzle known as ‘sudoku’. We see that this stochastic search-based algorithm, which uses simulated annealing, is able to complete
logic-solvable puzzle-instances that feature daily in many of the UK’s national newspapers. We also introduce a new method
for producing sudoku problem instances (that are not necessarily logic-solvable) and use this together with the proposed SA
algorithm to try and discover for what types of instances this algorithm is best suited. Consequently we notice the presence
of an ‘easy-hard-easy’ style phase-transition similar to other problems encountered in operational research. 相似文献
905.
This paper deals with the asymptotic analysis of the three-dimensional problem for a linearly elastic cantilever having an
open cross-section which is the union of rectangles with sides of order ε and ε
2, as ε goes to zero. Under suitable assumptions on the given loads and for homogeneous and isotropic material, we show that the
three-dimensional problem Γ-converges to the classical one-dimensional Vlassov model for thin-walled beams.
相似文献
906.
Denis V. Osin 《Archiv der Mathematik》2007,88(5):403-412
The aim of this paper is to show that free Burnside groups of sufficiently large odd exponent are non-amenable in a certain
strong sense. More precisely their left regular representations are isolated from the trivial representation uniformly on
finite generating sets. It follows that free Burnside groups are of uniform exponential growth. This answers a question of
de la Harpe.
This work has been partially supported by the NSF grant DMS-0605093 and by the RFBR Grant # 05-01-00892.
Received: 25 April 2006 相似文献
907.
Suppose F is a field of characteristic p?5, and that B is a p-block of the symmetric group Sn of defect 3. We prove that the Ext1-quiver of B is bipartite, with the bipartition being described in a simple way using the leg-lengths of p-hooks of partitions. 相似文献
908.
Qin-long Wang Yi-rong Liu 《应用数学学报(英文版)》2007,23(3):451-466
In this paper, we study the appearance of limit cycles from the equator and isochronicity of infinity in polynomial vector fields with no singular points at infinity. We give a recursive formula to compute the singular point quantities of a class of cubic polynomial systems, which is used to calculate the first seven singular point quantities. Further, we prove that such a cubic vector field can have maximal seven limit cycles in the neighborhood of infinity. We actually and construct a system that has seven limit cycles. The positions of these limit cycles can be given exactly without constructing the Poincare cycle fields. The technique employed in this work is essentially different from the previously widely used ones. Finally, the isochronous center conditions at infinity are given. 相似文献
909.
910.