Correlation Dimension in Fault Diagnosis of 600 MW Steam Turbine Generator

GP algorithm of correlation dimension computation is ameliorated which overcomes the shortage of traditional one. Improved process of GP algorithm takes the influence of temporal correlative pairs of points on correlation dimension into account and promotes the computational efficiency prominently. Iterative SVD method is applied to remove the influence of noise on the result of correlation dimension. The faults of steam flow turbulence and oil film disturbance which occur in 600MW Steam Turbine Generator are analyzed and whose correlation dimensions are computed. More distinct quantitative index than FFT is gained to distinguish two faults and it‘s of little importance to apply correlation dimension to study the influence of various factors on steam flow turbulence fault for nonexistence of convergent floor in correlation integral curve, which presents a new way to learn the operational function of large capacity steam turbine generator and carry out comprehensive condition monitoring.     

脑瘤占位的数字谱分析及其压缩谱阵

本文报告了利用脑电信号的数字分析技术诊断脑瘤占位所作的研究。分析结果以压缩谱阵以及按δ、θ、α、β频率范围作的统计功率百分比数值给出,临床上据此对脑瘤占位作出定侧定位判断。所作的九例分析与手术以及其它诊断结果相符合。对实际应用中的伪差问题也作了初步分析讨论。     

复倒频谱分析与相位展开的研究

复倒频谱不仅有解卷积分离和提取目标信号的作用,而且它保有相位信息,可作逆过程分析复原源信号,用于声源振源的识别和机械故障诊断.本文从理论上论述了复倒频谱的建立和相位展开,并在计算机,采用自适应积分方法,以堆栈形式极大限度地减少DFT的运算次数,通过应用实例回波检测的结果证明了复倒频谱分析的有效性.