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101.
Y. Ootao R. Kawamura Y. Tanigawa T. Nakamura 《Archive of Applied Mechanics (Ingenieur Archiv)》1998,68(10):662-676
Summary A neural network model is applied to optimization problems of material compositions for a functionally graded material plate
with arbitrarily distributed and continuously varied material properties in the thickness direction. Unsteady temperature
distribution is evaluated by taking into account the bounds of the number of the layers. Thermal stress components for an
infinite functionally graded material plate are formulated under traction-free mechanical conditions. As a numerical example,
a plate composed of zirconium oxide and titanium alloy is considered. In the optimization problem of minimizing the thermal
stress distribution, the numerical calculations are carried out making use of the neural network. The optimum material composition
is determined by taking into account the effect of temperature-dependence of material properties. The results obtained by
neural network and ordinary nonlinear programming method are compared.
Received 3 March 1998; accepted for publication 22 May 1998 相似文献
102.
Based on von Karman plate theory, the issue about nonlinear vibration for circular sandwich plates under circumjacent load with the loosely clamped boundary condition was researched. Nonlinear differential eigenvalue equations and boundary conditions of the problem were formulated by variational method and then their exact static solution can be got. The solution was derived by modified iteration method, so the analytic relations between amplitude and nonlinear oscillating frequency for circular sandwich plates were obtained. When circumjacent load makes the lowest natural frequency zero, critical load is obtained. 相似文献
103.
Based on the deformation hypothesis of Timoshenko's plates and the Boltzmann's superposition principles for linear viscoelastic materials, the nonlinear equations governing the dynamical behavior of Timoshenko's viscoelastic thick plates with damage are presented. The Galerkin method is applied to simplify the set of equations. The numerical methods in nonlinear dynamics are used to solve the simplified systems. It could be seen that there are plenty of dynamical properties for dynamical systems formed by this kind of viscoelastic thick plate with damage under a transverse harmonic load. The influences of load, geometry and material parameters on the dynamical behavior of the nonlinear system are investigated in detail. At the same time, the effect of damage on the dynamical behavior of plate is also discussed. 相似文献
104.
A general nonlinear theory for the dynamics of elastic anisotropic plates undergoing moderate-rotation vibrations is presented. The theory fully accounts for geometric nonlinearities (moderate rotations and displacements) by using local stress and strain measures and an exact coordinate transformation, which result in nonlinear curvatures and strain-displacement expressions that contain the von Karman strains as a special case. The theory accounts for transverse shear deformations by using a third-order theory and for extensionality and changes in the configuration due to in-plane and transverse deformations. Five third-order nonlinear partial-differential equations of motion describing the extension-extension-bending-shear-shear vibrations of plates are obtained by an asymptotic analysis, which reveals that laminated plates display linear elastic and nonlinear geometric couplings among all motions. 相似文献
105.
回顾了实心弹性薄板优化研究的发展历程。给出了由无限密和无限细的肋骨加强的环板在常肋骨密度时的解析解;采用精确刚度阵的有限元法计算了具有有限根肋骨加强的板的柔顺性,它低于光滑优化解的柔顺性。这些结果进一步说明近期文献中出现的枕头形的光滑解并不是几何受约束实心弹性薄板优化问题的全局最优解。 相似文献
106.
饱和地基上含刚核弹性圆板的竖向振动分析 总被引:8,自引:0,他引:8
基于作者提出的饱和土弹性波动方程,研究了饱和地基上含刚核弹性圆板在竖向集中谐和力作用下的振动特性。首先应用Hankel积分变换求解该饱和土波动方程,然后按混合边值条件建立起一组描述含刚核弹性圆板振动的对偶积分方程,并将其化为第二类Fredholm积分方程进行数值求解。文末给出了含刚核弹性圆板在饱和地基上振动的阻抗函数随无量纲频率a0的变化曲线,并考察了土的渗透系数,弹性板含刚域的大小以及板的柔度等参数对阻抗函数的影响,得出了一些有意义的结论。 相似文献
107.
108.
板壳塑性屈曲中的佯谬及其研究进展 总被引:6,自引:0,他引:6
本文详细论述了板壳塑性屈曲中的佯谬及其研究进展。并对现有的各种观点作了分析讨论。 相似文献
109.
110.