近似极限 meaning in Chinese

approximate limit

Firstly part of quadratic term of taylor series is chosen ; a low - dimension surface is used to approximate limit state surface ; and the modified reliability formula is derived
首次选取泰勒级数的部分二次项，用一个距原点最近点处拟合的超低维曲面近似极限状态面。
The method of multiple scales is used to determine the equations of modulation of amplitude and phase . the steady state response can be obtained by solving a couple of algebraic equations , which have been achieved by careful deduction under some conditions . and because of the complexity of the equations , programs are necessary to solve the equations mentioned above , and certain graphs are presented . based on chapter two , in chapter three , the method of multiple scales is introduced to the study of the multiple - dimensional nonlinear stochastic systems under random external excitation
在第二章基础上，第三章将多尺度法引入到相应的随机系统的研究中；严格推导了系统的约简方程，用矩方法求出稳态解应满足的方程，获得一些结果；并且数值模拟结果与理论推导的结果是一致的；并注意到，与其对应的确定性系统相比较，系统响应从周期解变为近似周期解，系统的相轨线从极限环变为扩大的近似极限环；随着激励带宽的增大，此扩大的近似极限环的宽度将增大。