A squeeze approach for electrocardiogram ST-segment detection based on R-wave and T-wave / 生物医学工程学杂志

ST-segment is the main clinical appearance in myocardial ischemia detection based on electrocardiogram (ECG) signals. However, it is highly sensitive to interferences (baseline wandering, postural changes, electrode interference, etc.), which cause the feature points of ECG ST-segment to be difficult to detect accurately. Currently, the common detection methods of ST-segment are: R+x and J+x, but they are affected badly by T-wave morphological variability and J point location. For these reasons, firstly we proposed a convenient and accurate approach for T-wave onset in this paper. It did not need to locate T-wave peak and was robust to baseline wandering and T-wave morphology. Secondly, we proposed a squeeze approach for ST-segment detection based on R-wave peak and T-wave onset. After the Long-Term ST database (LTST) verification, the proposed method has shown a good timeliness and robustness, and the accuracy of ST-segment detection has reached above 92%.

A method for measuring waveform parameters of electrocardiogram based on heartbeats extraction / 生物医学工程学杂志

Usually all heartbeats contribute to the calculation of electrocardiogram (ECG) waveform parameters, such as amplitude and interval, in which those low signal-to-noise-ratio (SNR) heartbeats actually produce a negative effect. In this paper is presented an approach for measuring ECG waveform parameters using template-based methods. Compared with Karhunen-Loeve (KL) template, average template has an advantage over KL template both on speediness and accuracy. Experimental results proved that this approach improved the statistical precision of ECG waveform parameters. In conclusion, this method makes the result of ECG auto analysis more accurate and reliable.

Study on Regulation of ECG Cycle Fluctuation / 航天医学与医学工程

Objective To investigate the regulation of fluctuation of beat to beat cardiac cycle.Methods A cardio-electric cycle consists of cardio-electric activity called P-T interval and cardio-electric resting TP segment,P-R interval and Q-T interval constitute P-T interval.The cardiac cycles fluctuate along with the time span fluctuation of sub waves and segments.This paper firstly extracted sub waves and segments based on signal processing methods,then discussed the contribution ratio of all waves and segments toward cardiac cycle fluctuation according to statistics.Results Experimental results indicated that the cardiac cycle fluctuation was mainly consistent with the change of TP segment.The P-T interval varied consistently with P-R interval foremost.Conclusion It is revealed that rule of cardiac cycle fluctuation is very useful for further research to figure out the cardiac function and mechanism.

Human Identification Based on ECG with Wavelet Decomposition and Data Fusion Method / 航天医学与医学工程

Objective A new method is researched based on ECG for human identification.Methods Three features of wave feature,wavelet feature,fusion feature were selected as the feature vectors for 35 normal subject ECGs,and correlation coefficient discriminate analysis was used for human identification. Results The other 40 sessions from 35 subjects were used for verifying the accuracy of each feature.They were 82.5%、87.5% and 95% respectively for wave feature,wavelet feature and fusion feature. ECG wavelet feature outperformed ECG wave feature. While ECG fusion feature performed better than either feature. Conclusion The verification experiment demonstrates that the technology of human identification based on ECG is feasible. ECG can be combined with other biometric features such as fingerprint for developing the multi-biometric identification system. The method proposed in this paper is simple,real-time and exact for human identification.