边界元与有限元的耦合法分析弹性地基梁与框架结构的协同工作

本文首先利用功的互等定理导出了弹性地基梁的四组基本解,建立了求解弹性地基梁的边界方程,进而由边界元及有限元的耦合理论对弹性地基梁及上部框架结构的协同工作进行了一系列的探讨。     

Inelastic dynamic response of R.C. beam column joints by using B.E.M.

A BEM formulation to obtain the inelastic response of R.C. Beam-Column joints subjected to sinusoidal loading along the boundary is presented. The equations of motion are written along with kinematical and constitutive equations. The dynamic reciprocal theorem is presented and the temporal dependence is removed by assuming steady state response.     

International Conference on Magentic Recording Media (M.R.M. '89)

The following topics are dealt with: materials for fabricating recording media; characteristics, design and performance of media; head-medium interactions; magnetooptic materials and recording; theory and fundamentals     

Magnetic behavior of MM′4B4-borides (M = Y.R.E.; M′ = Os,Ir; NdCo4B4-type structure)

Magnetic measurements on new ternary metal borides RE {Os, IR} ₄B₄ were performed within the temperature range: 80–300 K. Curie Weiss behavior is indicated by plots x_g versus T. Values for $\text{μ}{}_{\mathrm{<mtext>eff</mtext>}}\text{formula}$ unit compare well for RE elements in trivalent state. Ce in CeOs₄B₄ is found to be tetravalent.     

Monitoring the E.D.M. process by radio signals

Experimental studies are described to show that high-frequency radio observations provide a simple way to monitor the E.D.M. process and to distinguish between the effective spark and arc discharges. The paper also describes how radio frequency emitted during machining could be used to optimize the E.D.M. process.

It was found that radiation from the region of the gap between the electrode (tool) and the workpiece are significantly different when the following conditions occur: open voltage, sparking (effective machining), arcing and short circuit. However, a reliable technique was developed to monitor the rate of metal removal and machining efficiency during the E.D.M. process