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1.
A method for deriving one-dimensional wave propagation equations in thin inhomogeneous anisotropic bars based on the mathematical homogenization theory for periodic media is used to obtain equations governing the longitudinal and transverse vibrations of a homogeneous circular bar. The equations are derived up to O(ε8) terms and take into account variable body forces and surface loads. Here, ε is the ratio of the bar’s typical thickness to the typical wavelength. 相似文献
2.
Aernout C. D. van Enter 《Journal of statistical physics》1987,47(5-6):905-910
Some recent results on one-dimensional spin-glass models with polynomially decreasing interactions are described. 相似文献
3.
使用Monte Carlo模拟的方法得出了随机粗糙表面,在Kirchhoff近似的基础上,利用数值分析的方法分析了一维随机粗糙表面的散射特征,得出了一维随机粗糙表面散射分布曲线,我们还考虑了遮蔽效应的影响,并且讨论了Kirchhoff近似的有效性。 相似文献
4.
We consider a splitting finite-difference scheme for an initial-boundary value problem for a two-dimensional nonlinear evolutionary
equation. The problem is split into nonlinear and linear parts. The linear part is also split into locally one-dimensional
equations. We prove the convergence and stability of the scheme in L
2 and C norms.
Printed in Lietuvos Matematikos Rinkinys, Vol. 45, No. 3, pp. 413–434, July–September, 2005. 相似文献
5.
Yukio Iida Masahiro Shibutani Katsuhiko Kobayashi Kazuhiko Ohnuma Yoichi Miyake Toru Noda 《Optical Review》2006,13(2):87-92
The double-pass method is thought to obtain the point spread function (PSF) in human eyes based on two techniques: the symmetric
double-pass method using the same pupil size and the asymmetric double-pass method using a different pupil size. The symmetric
double-pass method provides autocorrelation of the retinal PSF and, thus, the modulation transfer function. The asymmetric
double-pass method provides low-frequency partial-phase information and the partial phase-retrieval algorithm is applied to
obtain the complete-phase information, and to estimate the PSF. The partial phase-retrieval algorithm is based on the iteration
method proposed by Fineup and Kowalczyk and requires a lengthy computation. In this study, we propose a new high-speed phase-retrieval
algorithm based on the property that the real and imaginary parts of optical transfer functions (OTFs) continuously change
in value. 相似文献
6.
Tatsien LI 《数学年刊B辑(英文版)》2007,28(3):265-282
In this paper, the authors consider the inverse piston problem for the system of one-dimensional isentropic flow and obtain that, under suitable conditions, the piston velocity can be uniquely determined by the initial state of the gas on the right side of the piston and the position of the forward shock. 相似文献
7.
以一维二次同余码(QCC)作为扩时模式,以光正交码(OOC)和QCC码作为频域跳频模式,通过时域和频域的组合,构造了适用于光码分多址(OCDMA)系统的QCC/QCC和QCC/OOC 2种跳频扩时码,并对码的容量及其相关性进行了分析。与一维QCC码相比,QCC/QCC跳频扩时码的容量扩大了p 1倍(p为码重),相关性得到改善,并且码字异相自相关限λa=1,互相关限λc=2;QCC/OOC跳频扩时码具有更大的码容量和更好的相关性,码字异相自相关限λa=0,所有码字按一定规律可分成p 1组(p为码重),每组内码字的互相关限λa=1,不同组间码字的互相关限λa=2。所得结果为光码分多址系统中跳频扩时码的构造提供了一种新的方法。 相似文献
8.
9.
Transition between layered and filamentary types of anisotropy in layered superconducting structures
D. A. Kuptsov 《Annalen der Physik》1992,504(4):296-301
A model of layered superconducting structure consisting of alternating anisotropic superconducting layers S1 and S2 with different transition temperatures is considered. It is shown that due to competition between two origins of anisotropy - effective-mass anisotropy of individual layers and proximity-induced anisotropy the effective anisotropy of the whole system signficiantly varies temperature. The components of the effective-mass tensor mc (along the anisotropy axis) and ma (perpendicular to the anisotropy axis) strongly depend upon temperature. This may lead to transition between layered (mc > ma) and quasi one-dimensional (mc < ma) types of anisotropy as well as to biaxial-type anisotropy which is also temperature dependent. The field distribution in a tilted vortex in a biaxial superconductor is calculated. The change in the properties of the vortex lattice with temperature in such systems is also investigated. The properties of YBa2Cu3Ox/PrBa2Cu3Oy multilayers are discussed in this connection. 相似文献
10.
研究一维半导体在外电磁场中的光吸收、涉及电子带间的直接跃迁与间接跃迁,考虑了电子-空穴相互作用的激子光吸收,导出一维半导体的光吸收系数公式。 相似文献