Using the eigen value、eigen vector and similarity transformation of direction cosine matrix,we have calculated the quaternion of finite rotation(α,β,γ,θ),and then used FORTRAN77 language to make a computing software,by which we have found the special effect of rotation axis r =(α,β,γ) and rotation angleθin the application of humen 3D - rotation.

In finite element analysis,the connecting element is treated as an element,its characteristics and some concrete problems in structure discretization and structure finite element analysis are elaborated.

The method for computing finite rotations is different from that of the translation displacements.

Basing on rotation vector method,Euler angles method and finite rotations method,the coning motion and its influence were discussed.

In describing the finite rotation in thin-shell structures,rotation vectors are adopted in the present work,which correspond to the orthogonal tensor that indicates normal rotations of the shell mid-surface.

Based on the explanation of the property and summation rule of finite rotation,the corresponding formulae of the variation of the axis of rotation is deduced.

By taking full advantage of the kinematic model of a rigid line and the finite rotation matrix, the simplification assumptions such as small displacement, small normal or shearing strain, small rotation, as well as small loading step etc can be abandoned.

Investigation of computing low frequency sound transfer function in small-enclosed room based on finite element method;

A smart structure embedded with SMA and PZT as united actuators is solved by finite element method.

And with the two models,the influences of gradient exponent on stress intensity factors,strain energy density factors and its initiating angles are analyzed using the finite element method.