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61.
Large strain fixed-end torsion of circular solid rubber bars is studied semi-analytically. The analyses are based on various
non-Gaussian network models for rubber elasticity, some of which were proposed very recently. Results are presented in terms
of predicted torque vs. twist curves and axial force vs. twist curves. In some cases, the predicted stress distributions are
also given. The sensitivity of the second-order axial force to the employed models is considered. The predicted results are
compared with experimental results found in the literature. 相似文献
62.
63.
The purpose of this research is to investigate the simple torsion problem for a solid circular cylinder composed of isotropic
hyperelastic incompressible materials with limiting chain extensibility. Three popular models that account for hardening at
large deformations are examined. These models involve a strain-energy density which depends only on the first invariant of
the Cauchy–Green tensor. In the limit as a polymeric chain extensibility tends to infinity, all of these models reduce to
the classical neo-Hookean form. The main mechanical quantities of interest in the torsion problem are obtained in closed form.
In this way, it is shown that the torsional response of all three materials is similar. While the predictions of the models
agree qualitatively with experimental data, the quantitative agreement is poor as is the case for the neo-Hookean material.
In fact, by using a global universal relation, it is shown that the experimental data cannot be predicted quantitatively by
any strain-energy density which depends solely on the first invariant. It is shown that a modification of the strain energies
to include a term linear in the second invariant can be used to remedy this defect. Whether the modified strain-energies,
which reflect material hardening, are a feasible alternative to the classic Mooney–Rivlin model remains an open question which
can be resolved only by large strain experiments.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
64.
65.
本文利用Luthar-Passi方法,研究了五次交错群A_5与六阶二面体群D_6直积的整群环的挠单位,得到了该群的Zassenhaus猜想成立. 相似文献
66.
Various classes of simple torsion modules are classified over the quantum spatial ageing algebra (this is a Noetherian algebra of Gelfand-Kirillov dimension 4). Explicit constructions of these modules are given and for each module its annihilator is found. 相似文献
67.
68.
圆环在均布扭力矩作用下的变形特殊且容易发生跳跃,不考虑稳定性而得到的一些结论将可能不存在。本文利用最小势能原理导出圆截面圆环在均布扭力矩作用下的平衡路径,并根据系统稳定性的能量判据,对圆环的平衡稳定性、变形与运动过程进行分析,最后得到稳定平衡状态下圆环横截面上的内力最大值。 相似文献
69.
Gaurav Thakur 《Journal of Functional Analysis》2011,260(8):2283-2299
We study some problems related to the effect of bounded, additive sample noise in the bandlimited interpolation given by the Whittaker-Shannon-Kotelnikov (WSK) sampling formula. We establish a generalized form of the WSK series that allows us to consider the bandlimited interpolation of any bounded sequence at the zeros of a sine-type function. The main result of the paper is that if the samples in this series consist of independent, uniformly distributed random variables, then the resulting bandlimited interpolation almost surely has a bounded global average. In this context, we also explore the related notion of a bandlimited function with bounded mean oscillation. We prove some properties of such functions, and in particular, we show that they are either bounded or have unbounded samples at any positive sampling rate. We also discuss a few concrete examples of functions that demonstrate these properties. 相似文献
70.
A simple and commonly used method to approximate the total claim distribution of a (possibly weakly dependent) insurance collective is the normal approximation. In this article, we investigate the error made when the normal approximation is plugged in a fairly general distribution-invariant risk measure. We focus on the rate of convergence of the error relative to the number of clients, we specify the relative error’s asymptotic distribution, and we illustrate our results by means of a numerical example. Regarding the risk measure, we take into account distortion risk measures as well as distribution-invariant coherent risk measures. 相似文献