The displacement mode parameters and strain mode parameters are combined withneural networks techniques on the studies of damage detection of structures.

Most of structural damage identification is based on the results of displacement mode. The limitation of the results makes the identifying effects not well.

The chaotic motions of axial compressed nonlinear elastic beam subjected to transverse load were studied. Considering material and geometric nonlinearity, nonlinear partial differential equation of the system was derived. Under ideal displacement conditions,one order differential equations were devived and solved.

And furthermore, by studying the physicalmeanings of the matrix corresponding to the modes of vibration and force, and considering the physical of eigenfrequency itself, a new criterion is found to distinguish equal eigenfrequency and close eigenfrequency.

The theory and method of direct identification of displacement and strain modes for vibration modal test with strain guages are described. The concept of strain mobility, strain displacement relationships and derivation of formulae of transfer functions in terms of strains are considered.

The displacement mode of development is generated in a relatively short distance, and the fully developed displacement train concentrates sample components even from an elongated spot.

Compared with the displacement mode shape, the variations of strain mode shapes at each point are quite different.

The modal parameters considered are modal frequency, displacement mode shape (DMS) and strain mode shape (SMS).

We study a time-independent displacement mode which is an exact solution of Vlasov-Poisson equation for spherical stellar systems and we show that it corresponds to an aspherical mode.

The research with the ABx system indicated that these mixed mode interaction systems could be successfully employed in the displacement mode using DEAE-dextran as the displacer.

The theory and method of direct identification of displacement and strain modes for vibration modal test with strain guages are described. The concept of strain mobility, strain displacement relationships and derivation of formulae of transfer functions in terms of strains are considered. The system modal

In this paper the problem was discussed in which the flextural rigidity and density of the Euler-Bernoulli Beam were solved from some of the displacement modes or the strain modes and the corresponding frequencies of a cantilever or a pinned-pinned beam. The necessary and sufficient conditions for the unique ex istence of a solution to the problem have been set up. An algorithm was proposed and numerical calculations were carried out. Examples and analysis both showed that much better results could be attained...

In this paper the problem was discussed in which the flextural rigidity and density of the Euler-Bernoulli Beam were solved from some of the displacement modes or the strain modes and the corresponding frequencies of a cantilever or a pinned-pinned beam. The necessary and sufficient conditions for the unique ex istence of a solution to the problem have been set up. An algorithm was proposed and numerical calculations were carried out. Examples and analysis both showed that much better results could be attained if the strain modes instead of the displacement modes were employed in the calculations. Although the investigations were made only on the cantilever and the pinned-pinned beam, the ideas in this paper worked equally well in the study of the mode inverse problem of beams subject to other boundary restraints.

This paper presents the odd function with four terms which can be used to make the curve fitting of the stress-strain for various materials precisely.Furthermore,the displacement modes of elastic beams and the unknown coefficients are introduced to form the elasto-plastic displacement field.According to the principle of minimum potential energy,the unknown coefficients as well as the close solution can be determined.Several examples are taken to be investigated by using this method.Good agreement is obtained...

This paper presents the odd function with four terms which can be used to make the curve fitting of the stress-strain for various materials precisely.Furthermore,the displacement modes of elastic beams and the unknown coefficients are introduced to form the elasto-plastic displacement field.According to the principle of minimum potential energy,the unknown coefficients as well as the close solution can be determined.Several examples are taken to be investigated by using this method.Good agreement is obtained from the theoritical and experimental results.