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171.
172.
The transverse vibrations of an Euler-Bernoulli beam with axial tension P and axial white noise forcing are given by
173.
Fule Li Kaimei Huang 《高等学校计算数学学报(英文版)》2007,16(3):233-252
In this paper,the numerical approximation of a Timoshenko beam with bound- ary feedback is considered.We derived a linearized three-level difference scheme on uniform meshes by the method of reduction of order for a Timoshenko beam with boundary feedback.It is proved that the scheme is uniquely solvable,unconditionally stable and second order convergent in L_∞norm by using the discrete energy method. A numerical example is presented to verify the theoretical results. 相似文献
174.
Hua Ning LIU Wen Peng ZHANG 《数学学报(英文版)》2007,23(1):77-82
The main purpose of this paper is to use the generalized Bernoulli numbers, Gauss sums and the mean value theorems of Dirichlet L-functions to study the asymptotic property of one class of number-theoretic functions, and to give four interesting hybrid mean value formulae. 相似文献
175.
The fourth power mean of the general 2-dimensional Kloostermann sums mod <Emphasis Type="Italic">p</Emphasis> 下载免费PDF全文
The main purpose of this paper is using the analytic methods and the properties of Gauss sums to study the computational problem of one kind fourth power mean of the general 2-dimensional Kloostermann sums mod p, and give an exact computational formula for it. 相似文献
176.
司守奎 《高校应用数学学报(英文版)》1999,14(4)
In this paper,the boundary stabilization of the Timoshenko equation of a nonuniform beam,with clamped boundary condition at one end and with bending moment and shear force controls at the other end,is considered.It is proved that the system is exponentially stabilizable when the bending moment and shear force controls are simultaneously applied.The frequency domain method and the multiplier technique are used. 相似文献
177.
V. P. Derevenskii 《Mathematical Notes》1999,66(1):51-61
Sufficient conditions for the solvability in quadratures of systems of matrix linear ordinary differential equations of first
order with one-sided multiplication by variable matrix coefficients are given in this paper. These conditions are stated in
terms of the theory of Lie algebras. We consider matrix equations of higher orders that are equivalent to such systems. An
illustrative example is considered.
Translated fromMatematicheskie Zametki, Vol. 66, No. 1, pp. 63–75, July, 1999. 相似文献
178.
179.
Active control of bending waves in a periodic beam by the Timoshenko beam theory is concerned. A discussion about the possible wave solutions for periodic beams and their control by forces is presented. Wave propagation in a periodic beam is studied. The transfer matrix between two consecutive unit cells is obtained based on the continuity conditions. Wave amplitudes are derived by employing the Bloch-Floquet theorem and the transfer matrix. The influences of the propagating constant on the wave amplitudes are considered. It is shown that vibrations are still needed to be suppressed in the pass-band regions. Wave-suppression strategy described in this paper is employed to eliminate the propagating disturbance of an infinite periodic beam. A minimum wave-suppression strategy is compared with the classical wave-suppression strategy. 相似文献
180.
基于二维热弹性力学理论,研究均匀热荷载作用下层合简支梁的弹性力学解.首先导出均匀温度场中满足控制微分方程和两端简支边界条件的单层梁的弹性力学解,然后利用层间界面位移和应力必须连续的条件,递推得到底层梁与顶层梁间的位移和应力关系.最后根据层合梁上下表面的边界条件确定待定系数,带回递推公式得到整个层合梁的应力和位移分布.本文方法的计算结果有很好的收敛性.与有限元软件的结果对照说明了本文方法的精确性.最后,研究了不同的变温对层合简支梁的位移和应力的影响,结果显示每个层间界面在x方向的应力是不连续.随着温度的升高,梁的最大位移相应地增大.温度越高,位移沿厚度变化的速率越大. 相似文献