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141.
We report the inverse Meyer–Neldel (MN) rule in the thermally activated crystallization of a hybrid composite of phenol formaldehyde using two experimental approaches. In the first experiment, the annealing time dependence of the pre-exponential factor K 0 and the activation energy of crystallization E c were studied. In the second experiment, the annealing temperature dependence of the same parameters was investigated. We observed the inverse Meyer–Neldel rule between the pre-exponential factor K 0 and the activation energy of crystallization E c in both cases. 相似文献
142.
通过分层立方网络HCNn (n≥3)的容错性分析,从理论上探讨了分层立方网络基于比较模型的条件诊断度,并证明其条件诊断度为tc(HCNn)=3n?2,大约是传统诊断度(t(HCNn)=n+1)的3倍. 相似文献
143.
S. Oliffson Kamphorst 《Journal of statistical physics》1986,45(3-4):369-393
A proof of the existence of a mixed ferromagnetic (or antiferromagnetic)-spin-glass fixed point for an Ising spin-glass model on the diamond hierarchical lattice is given. 相似文献
144.
Huan-You Wang Hui Xu Tie-Tie Huang Chao-Sheng Deng 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,62(1):39-43
The density function perturbation theory (DFPT) is employed to study
the linear thermal expansion and heat capacity at constant pressure
(with the quasiharmonic approximation) for wurtzite GaN. The
calculated results of linear thermal expansion coefficient and heat
capacity at constant pressure are compared with the available
experimental data in a wide temperature range. Generally these
properties calculated agree well with experimental data except at
high temperature, thus it suggests the thermal expansion and heat
capacity can be well calculated from this first-principle approach. 相似文献
145.
对格上Erceg式p.q.(p.)度量的注记 总被引:4,自引:0,他引:4
本文的主要结果是大幅度地简化了Erceg引入的不分明度量的无点化定义,建立了相应的点式刻画. 相似文献
146.
A new method and corresponding numerical procedure are introduced to estimate scaling exponents of power-law degree distribution and hierarchical clustering func tion for complex networks. This method can overcome the biased and inaccurate faults of graphical linear fitting methods commonly used in current network research. Furthermore, it is verified to have higher goodness-of-fit than graphical methods by comparing the KS (Kolmogorov-Smirnov) test statistics for 10 CNN (Connecting Nearest-Neighbor)networks. 相似文献
147.
In this paper we prove that the equational class generated by bounded BCK‐algebras is the variety generated by the class of finite simple bounded BCK‐algebras. To obtain these results we prove that every simple algebra in the equational class generated by bounded BCK‐algebras is also a relatively simple bounded BCK‐algebra. Moreover, we show that every simple bounded BCK‐algebra can be embedded into a simple integral commutative bounded residuated lattice. We extend our main results to some richer subreducts of the class of integral commutative bounded residuated lattices and to the involutive case. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
148.
The efficiency of hierarchical matrices is based on the approximate evaluation of usual matrix operations. The introduced approximation error may, however, lead to a loss of important matrix properties. In this article we present a technique which preserves the positive definiteness of a matrix independently of the approximation quality. The importance of this technique is illustrated by an elliptic mixed boundary value problem with tiny Dirichlet part. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
149.
Jean B. Lasserre 《Proceedings of the American Mathematical Society》1998,126(1):189-194
We consider a linear sytem in a Banach lattice and provide a simple theorem of the alternative (or Farkas lemma) without the usual closure condition.
150.
Summary A tool for analyzing spatio-temporal complex physical phenomena was recently proposed by the authors, Aubry et al. [5]. This
tool consists in decomposing a spatially and temporally evolving signal into orthogonal temporal modes (temporal “structures”)
and orthogonal spatial modes (spatial “structures”) which are coupled. This allows the introduction of a temporal configuration
space and a spatial one which are related to each other by an isomorphism. In this paper, we show how such a tool can be used
to analyze space-time bifurcations, that is, qualitative changes in both space and time as a parameter varies. The Hopf bifurcation
and various spatio-temporal symmetry related bifurcations, such as bifurcations to traveling waves, are studied in detail.
In particular, it is shown that symmetry-breaking bifurcations can be detected by analyzing the temporal and spatial eigenspaces
of the decomposition which then lose their degeneracy, namely their invariance under the symmetry. Furthermore, we show how
an extension of the theory to “quasi-symmetries” permits the treatment of nondegenerate signals and leads to an exponentially
decreasing law of the energy spectrum. Examples extracted from numerically obtained solutions of the Kuramoto-Sivashinsky
equation, a coupled map lattice, and fully developed turbulence are given to illustrate the theory. 相似文献