Aiming at the nonstationary characteristic of the dynamic loads and the relation between the responses and the frequency response functions , by use of the responses only , some novel theories are conducted to develop force identification and impact location approaches in this dissertation 本文就动态载荷的非平稳特性对有关前沿理论作了系统研究,着眼于结构响应输出与频率响应函数间的关系,建立了一类单独利用响应数据进行动载荷及其位置识别的新颖理论体系与方法。
The signal process function of the software include these function : digital filter , windowing , auto - correlation function and cross - correlation function , mean and variance , probability density function and probability distribution function statistic ; auto - power spectrum , cross - power spectrum , frequency response function , coherence function , cepstrum analysis based on fft ( fast fourier transfer ) ; joint time - frequency analysis based on stft ( short - time fourier transfer ) 软件的处理功能包括:数字滤波、时域加窗、自相关与互相关处理、均值和方差计算、概率密度和概率分布函数计算;在快速傅立叶变换( fft )基础上计算自功率谱、互功率谱、频率响应函数、相干函数、倒频谱分析;基于短时傅立叶变换( stft )的联合时频分析等。
The method is as follows , at first , to calculate the frequency response function of structure corresponding every blasting syntony ponderance , then to calculate the response of structure under this syntony ponderance by using frequency response function , at last , the response of the whole system can be worked out by superposition 计算方法是先计算每一爆破谐分量对应于结构的频响函数,然后用频响函数计算出结构在此谐分量下的响应,最后用叠加法得到整个系统的响应。
In the process of solving , poles are obtained from recurrent formula , modal vector are obtained from superposition formula not residuary . decoupled equation is derived when vibration source is part correlation , severely coupling appears in the process of input and output then frequency response function cannot directly get according to method mentioned above , decoupling is first problem 当输入完全相关时,频响函数无解,可绕过频响函数,直接运用线性系统的迭加原理来求响应,极点由递归公式得出,模态矢量由叠加公式求出,而不是由留数求得的相应的公式。