The identification of the inter-electrode gap size in the high frequency group pulse micro-electrochemical machining （HGPECM） is mainly discussed. The auto-regressive（AR） model of group pulse current flowing acros...The identification of the inter-electrode gap size in the high frequency group pulse micro-electrochemical machining （HGPECM） is mainly discussed. The auto-regressive（AR） model of group pulse current flowing across the cathode and the anode are created under different situations with different processing parameters and inter-electrode gap size. The AR model based on the current signals indicates that the order of the AR model is obviously different relating to the different processing conditions and the inter-electrode gap size; Moreover, it is different about the stability of the dynamic system, i.e. the white noise response of the Green＇s function of the dynamic system is diverse. In addition, power spectrum method is used in the analysis of the dynamic time series about the current signals with different inter-electrode gap size, the results show that there exists a strongest power spectrum peak, characteristic power spectrum（CPS）, to the current signals related to the different inter-electrode gap size in the range of 0～5 kHz. Therefore, the CPS of current signals can implement the identification of the inter-electrode gap.展开更多
功率谱分析是目前心率变异性分析的主要方法。文中对比周期图法简要介绍了自回归模型(Autoregressive models)功率谱估计的原理 ,并由此出发对心率变异信号进行功率谱分析。心率变异信号功率谱可划分为代表不同生理意义的特征谱段。医...功率谱分析是目前心率变异性分析的主要方法。文中对比周期图法简要介绍了自回归模型(Autoregressive models)功率谱估计的原理 ,并由此出发对心率变异信号进行功率谱分析。心率变异信号功率谱可划分为代表不同生理意义的特征谱段。医学上通常采用这些谱段中的所谓低频谱段与高频谱段的比值 L F/HF作为衡量心脏生理功能的一项有效指标。文中探讨了根据当前心率变异功率谱特征谱段划分方案得出的 L F/HF指标的有效性 ,提出了不同的特征谱段划分方案 ,并且从统计学的观点对由该方案得出的 LF/HF指标进行了论证 ,最后证明它的有效性及显著性均优于当前的划分方案得出的 L F/HF指标。展开更多
基金This project is supported by the 10th Five-year Plan Pre-research Project Foundation of China Weapon Industry Company, China(No.42001080701).
文摘The identification of the inter-electrode gap size in the high frequency group pulse micro-electrochemical machining （HGPECM） is mainly discussed. The auto-regressive（AR） model of group pulse current flowing across the cathode and the anode are created under different situations with different processing parameters and inter-electrode gap size. The AR model based on the current signals indicates that the order of the AR model is obviously different relating to the different processing conditions and the inter-electrode gap size; Moreover, it is different about the stability of the dynamic system, i.e. the white noise response of the Green＇s function of the dynamic system is diverse. In addition, power spectrum method is used in the analysis of the dynamic time series about the current signals with different inter-electrode gap size, the results show that there exists a strongest power spectrum peak, characteristic power spectrum（CPS）, to the current signals related to the different inter-electrode gap size in the range of 0～5 kHz. Therefore, the CPS of current signals can implement the identification of the inter-electrode gap.
文摘功率谱分析是目前心率变异性分析的主要方法。文中对比周期图法简要介绍了自回归模型(Autoregressive models)功率谱估计的原理 ,并由此出发对心率变异信号进行功率谱分析。心率变异信号功率谱可划分为代表不同生理意义的特征谱段。医学上通常采用这些谱段中的所谓低频谱段与高频谱段的比值 L F/HF作为衡量心脏生理功能的一项有效指标。文中探讨了根据当前心率变异功率谱特征谱段划分方案得出的 L F/HF指标的有效性 ,提出了不同的特征谱段划分方案 ,并且从统计学的观点对由该方案得出的 LF/HF指标进行了论证 ,最后证明它的有效性及显著性均优于当前的划分方案得出的 L F/HF指标。
