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51.
不可压超弹性材料中的空穴分叉   总被引:7,自引:5,他引:2  
研究了一种不可压Valanis-Landel材料超弹性球体在表面死载荷作用下的球形空穴的分叉问题。给出了空穴分叉问题的解析解,讨论了空穴生成时的应力间断和应力集中问题。通过能量比较判断了解的稳定性,并分析了球体中预存微孔的增长情况。  相似文献   
52.
IntroductionHorgan[1] reviewedthecavitatedbifurcationproblemforhyper_elasticmaterials,includinginhomogeneousandanisotropicmaterialsaswellashomogeneousandisotropicmaterials .Forincompressiblematerials,HorganandPence[2 ,3 ] examinedtheeffectofmaterialinhomogeneityontheformationandgrowthofvoidandobtainedananalyticsolutionofthecavitatedbifurcationproblemforasolidspherecomposedoftwoneo_Hookeanmaterials.Thebifurcationmayoccurnotonlytotherightbutalsototheleftforthecomposedsphere .Thestabilitiesofth…  相似文献   
53.
用燕尾突变理论来讨论交通流预测   总被引:4,自引:0,他引:4  
唐铁桥  黄海军 《数学研究》2005,38(1):112-116
交通流本身是一个动态过程,运用尖点突变理论来分析交通流的预测时只考虑了流量和密度,而忽视了时间因素,这本身就不是很合理的.基于这个基础之上,采用燕尾突变理论来讨论交通流预测时将时间因素考虑进去,并给出一个算例表明了此方法预测的效果更符合现实。  相似文献   
54.
This paper reviews a variety of issues related to speculative bubbles, especially those involving nonlinear dynamics. Models of irrational bubbles, rational bubbles, and bubbles arising from heterogeneous agents with varying degrees of knowledge or rationality are examined. The latter are shown to be prone to nonlinear dynamics with catastrophic discontinuities, chaos, and other forms of complex phenomena. Empirical evidence regarding the existence of bubbles in various markets is reviewed, eventually examining strong evidence in closed-end country mutual funds markets.  相似文献   
55.
A spectral decomposition of the Frobenius–Perron operator is constructed for one-dimensional maps with intermittent chaos, using the method of coherent states. A technique using the spectral density function is applied to the the well-known cusp map, which generates weak type-II intermittency. Higher-order corrections are obtained to the leading 1/t long-time behavior of the xx autocorrelation.  相似文献   
56.
In this paper, the theory of dynamical systems is employed to investigate loop waves and cusp waves of the Fujimoto-Watanabe equation. These waves contain solitary loop waves, periodic loop waves, peakons and periodic cusp waves. Under fixed parameter conditions, their exact explicit parametric expressions are given.  相似文献   
57.
The singular behavior of functions is generally characterized by their Hölder exponent. However, we show that this exponent poorly characterizes oscillating singularities. We thus introduce a second exponent that accounts for the oscillations of a singular behavior and we give a characterization of this exponent using the wavelet transform. We then elaborate on a grand-canonical multifractal formalism that describes statistically the fluctuations of both the Hölder and the oscillation exponents. We prove that this formalism allows us to recover the generalized singularity spectrum of a large class of fractal functions involving oscillating singularities.  相似文献   
58.
We argue with Kryachko's criticism [Int J Quantum Chem 2005, 103, 818] of the original proof of the second Hohenberg‐Kohn theorem. The Kato cusp condition can be used to refute a “to‐be‐refuted” statement as an alternative to the original proof by Hohenberg and Kohn applicable for Coulombic systems. Since alternative ways to prove falseness of the “to‐be‐refuted” statement in a reduction ad absurdum proof do not exclude each other, Kryachko's criticism is not justified. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007  相似文献   
59.
This article proposes a model for chemical reactivity that involves singularities (“catastrophes”) in the timing of bond‐making and bond‐breaking events. The common stapler is a good mechanical analogy: As hand‐pressure is increased on the machine, the staple hardly changes its configuration until the staple suddenly bends. This is viewed as a singularity or catastrophe, defined classically as an abrupt change resulting from a smooth increase or decrease in external conditions (pressure in the case of a stapler, distance in the case of reactivity). Although experimental observations are provided to support the singularity effect, the model remains a heterodox notion at the present time.  相似文献   
60.
In this paper, we employed the bifurcation method and qualitative theory of dynamical systems to study the peakons and periodic cusp waves of the generalization of the Camassa‐Holm equation, which may be viewed as an extension of peaked waves of the same equation. Through the bifurcation phase portraits of traveling wave system, we obtained the explicit peakons and periodic cusp wave solutions. Further, we exploited the numerical simulation to confirmthe qualitative analysis, and indeed, the simulation results are in accord with the qualitative analysis. Compared with the previous works, several new nonlinear wave solutions are obtained. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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