Trefftz间接法解自由面渗流问题

渗流问题是岩体水力学研究的重点之一，较常规的有限元法和传统的边界元法而言，Trefftz型边界元法具有程序简单、计算量小及无须奇异积分等特点。本文给出定常和非定常自由面渗流问题的Trefftz解法，计算结果表明，该法收敛性好，结果比较精确。  

Existence and stability of traveling waves in periodic media governed by a bistable nonlinearity

We prove the existence of multidimensional traveling wave solutions of the bistable reaction-diffusion equation with periodic coefficients under the condition that these coefficients are close to constants. In the case of one space dimension, we prove their asymptotic stability.  

Discriminating on dynamical stability of biped walking

In paper, a biped with 7 rigids and 12 degrees of freedom is taken as a research mould. The discriminating conditions on dynamical walking stability are derived and discussed in detail. The discriminating condition could be used to check biped motive planning and to modify it.  

VIBRATION OF CANTILEVERS WITH ROUGH SURFACES

We study the effect of surface roughness on the resonance frequency of micro-cantilever sensors. The analysis demonstrates that surface roughness can enhance, decrease or even annul the effect of surface stress on the resonance frequency, depending on the surface inclination angle and the Poisson ratio of the coating film on the cantilever.