### ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

## 4pSAb5. Sensitivity analysis of structural eigenfrequency to plate design
parameters by using neural network.

**Z. Q. Yu
**

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L. H. Yam
**

**
T. P. Leung
**

**
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*Dept. of Mech. & Marine Eng., Hong Kong Polytech. Univ., Hung Hom,
Kowloon, Hong Kong
*

*
*
The dynamic characteristics of plate structure can be improved by
arranging the natural frequencies of the system in specified ranges. The
sensitivities of structural dynamic response to design parameters can provide
the essential gradient information for deriving efficient optimization
procedures. They are used to form an approximate problem for solving the
original structural optimization problem, while the sensitivity of geometric
parameters to frequency can provide the essential gradient information for
deriving efficient design procedures. In this paper, first the training set of
neural network is generated by the finite-element method; second, the original
design of a cantilever rectangular plate with multifrequency constraints is
obtained by using the neural network; third, the sensitivities of the plate
eigenvalue to design parameters (i.e., (cursive beta) f/(cursive beta)R[sub i])
around the point of original geometric design are obtained by using the trained
neural network. Finally, the sensitivities of design parameters to eigenvalue
(i.e., (cursive beta)R/(cursive beta)f[sub i]) are also obtained by using the
trained neural network. The influence of frequency on geometric parameters, as
well as the influence of geometric parameters on frequency, is also discussed.