Sheng wu yi xue gong cheng xue za zhi = Journal of biomedical engineering = Shengwu yixue gongchengxue zazhi
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Sheng Wu Yi Xue Gong Cheng Xue Za Zhi · Oct 2006
[The application of adaptive algorithm and wavelet transform in the filtering of ECG signal].
Electrocardiographic (ECG) signal are a kind of basic physiological signals of human body, and are very important in clinical diagnosis. But the ECG signals from body surface are often interfered by noises such as 50 Hz noise, baseline displacemant, electromyography (EMG) noise and edv. ⋯ To eliminate the ECG signals noises mentioned above,this paper adopts LMS adaptive algorithm and wavelet transform theory to design three kinds of digital adaptive filters-adaptive noise cancellation filter, wavelet transform filter and adaptive signal dividing filter to filter the corresponding noises. The results show that the three kinds of noises existing in the ECG signal have been efficiently eliminated.
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Sheng Wu Yi Xue Gong Cheng Xue Za Zhi · Aug 2006
[Speaker identification based on Mel frequency cepstrum coefficient and complexity measure].
In present, the most basically used parameters for speaker identification are linear predictive coding (LPC) parameter, Mel frequency cepstrum coefficient(MFCC), etc. First in this paper only MFCC was used as the parameter and then Lempel-Ziv Complexity was combined with MFCC as parameters. The text-dependent recognition rate of 50 speakers increased from 42% to 80% and the text-independent recognition rate of 50 speakers increased from 60% to 72%. This test shows that Lempel-Ziv complexity, as a new parameter, can be applied to speaker identification.
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Sheng Wu Yi Xue Gong Cheng Xue Za Zhi · Apr 2006
[R-wave detection of ECG signal by using wavelet transform].
The detection of R-wave of ECG is essential to the analysis of the heart rate variability (HRV). In this paper, an R-wave detection method using wavelet transform(WT) is presented in line with the principle of discrete wavelet transform(DWT) and multi-resolution technique (MRT). ⋯ The results show that R-wave could be detected accurately and localized precisely by this method, even when the patient was seriously sick or the signal was disturbed by noise. Consequently the method has a quite high locating precision (its error is not more than two sampled points and about 85 percent of the points of R-wave in ECG signal are localized precisely) and the correct detection rate of R-wave is 99.8% by using wavelet transform, so this method is quite feasible.
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Sheng Wu Yi Xue Gong Cheng Xue Za Zhi · Apr 2006
[A digital subtraction angiography system based on LUT algorithms].
Look-up table (LUT) algorithms have been widely used in digital signal processing, but the article on the application of LUT algorithms in digital subtraction angiography was rarely reported. In this article, the effect of different LUT algorithms on digital subtraction angiography images is introduced. The result reveals that different LUT algorithms can bring about different effects of image. Based on analysis and comparison, we deem it possible to acquire improved images of DSA by use of some LUT algorithms with image processing.
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Sheng Wu Yi Xue Gong Cheng Xue Za Zhi · Dec 2005
[Numerical simulation of the relationship between blood pressure and blood stream of arteries].
The quantitative relationship between blood pressure and blood stream of arteries, which is delineated by hemodynamics, is rather complex to understand and analyze mathematically. An equivalent simulated mathematical model was utilized to numerically describe this sort of relationship. ⋯ Some important conclusions about quantitative relationship of the layered flowage were drawn through the simulation results. The research results presented in this paper have important reference value in respect of quantitative research of circulation physiology and clinical diagnosis and analysis of some illness within circulation system.