Abstract:A method is presented in this paper which uses an incomplete set of complex modal parameters identified from the experimental date to modify the structural dynamic model. The method, not requiring iteration and being programed easily,is suitable for the complex structures with general viscous damping in improving the analytical mass, damping and stiffness matrix madel of a structure with a set of minimum changes in the analytical matrics, so as to force the eigensolutions to agree with the test measurement. An example is given to demonstrate the validity of this proposed method.

Abstract:The feasibility of treating relative excitation as sigle-point excitation is demonstrated by comparing the modal analvsis results of two types of gearhobbing machine. Two kinds of excitation tests are carried out on either cf the two machines and the close values of modal parameters are given by the HP5423A Structure Dynamics Analyzer, The transfer function of relative excitation developed in this paper is examined by synthesizing the modal parameters.

Abstract:本文讨论了多相固体的本构等效理论和应用分析方法,提出多相体的等效变形梯度、等效应变、等效第一类P-K应力和等效应力的表面位移和表面力的定义式,使能考虑相间结合缺陷引起的位移间断情况。文章论证了所述等效理论具有的形变功率等值性和线弹性条件下的应变能等值性。作为例子,文章介绍了空心微珠复合材料考虑相间结合缺陷的等效杨氏模量计算式。

Abstract:Based on references [1, 2, 3], we designed a set of device of the self-excited oscillation cavitating jet. Its cavitation mechanism and the result of jet impact block are analysed. With erosive volume as the object, the effect of the self-excited oscillation cavitating jet is compared with that of conventional continuous jet under the same condition. It is found cxperimeetally that the position of suction air and the air quantities and the geometrical parameters of the device have great effect on the erosive effects of the self-excited oscillation cavitating jet. In certain range of stand off distance, it's not obvious that the erosive effects of the self-excited oscillation cavitating jet changed with stand off distance for pulse cavitating jet and cavitation bubblies and droplet impinging on the target. Compared with continuous jet, the erosive vo-l ume and area of the self-excited oscillation cavitating jet is more than one time larger than the continuous jet.

Abstract:Some properties of feasible direction in the convx case are generalized to, the corresponding properties in generalized covex case and their applications for multiobjective mathematical programming are discussed in this paper.

Abstract:We show in this paper, a necessary and sufficient condition on hereditary K-Helly hypergraphs and conformal hypergraphs and their equivalence.

Abstract:The paper presents a Monte-carlo method for reliability evaluation of large scale composite generation transmission systems. The method, which possesses coputational rapidity and sufficient accuracy,is based on combining the dispersed sampling techique with the analysis approach and the optimization model of power not supplied. Because the amount of calculation increases only linearly with, the number of elements, it is specially sui- table for large scale systems. The Monte-carlo sampling draws more near the real situation than determinate state enumeration in simulating occurrence of power system outages. Also, the method can be easily generalized to involve multi-states of elements, multi-levels and stochastic distribution of loads. The results of IEEE-RTS, as example, are given and compared with ones obtained by using the other two methods.