The rhythm of the undulated forms of blood and oxygen in the early hepatocirrhosis was irregular. The main frequency peak of auto-power spectrum was found to move back to the rang 1.0~1.5 Hz and multi-peak was seen.
This paper analyses the noise refrain principle of current Input and Output Noise Models in detail,andfind the reason which causes the deviation is due to the Auto-power Spectrum,in which the noise can't beeliminated by averaging.
In the first session the fans vibration on-line monitoring system is realized with VC language, also compile auto power spectrum density function, cross power spectrum density function, autocorrelation function and cross correlation function etc spectral analysis function to carry through simple offline fault diagnosis.
Based on the analysis of shocking test of many compactive samples, the curve and formulas according the relation of the auto power spectrum peak of shock response, the compaction and the water content are given.
An approach for identifying the modal parameters of a civil engineering structure by means of the self power spectrum analysis of its output response under the random excitation of environments is presented.
In this paper the vibrational characteristics of the earth surface collided by a free falling hammer are first analysed. The dynamic model is established and the displacement,velocity and acceleration of the vibration system are obtained. The self power spectrum of the vibration system are disccused by using FFT.