By using the method of small parameter expansions the present boundary-value problem is solved. Thus the formula in the secondapproximation for the stress field is obtained.
本文运用小参数展开法求解了这一大变形问题，获得应力场的二级近似公式。
2
The secondapproximation of the solution is of the same accuracy as theory of thin shells, and the first approximation is also sufficiently precise for engineering computation.
二次近似解达到薄壳理论所具有的精度，一次近似解也具有足够精度。
3
According to the dual theory, the dual programming was used to map the original problem exactly and the secondapproximation of the dual problem was set up by Taylor's expansion.