Wyniki wyszukiwania - BazTech

1

A pilot study on the effect of music-heart beat feedback system on human heart activity

Nomura S., Yoshimura K., Kurosawa Y.

Journal of Medical Informatics & Technologies

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2013

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Vol. 22

251--256

EN

We developed a music-heart beat feedback system to test the efficacy of the entrainment between music and human heart beat. As a result of regulating the music tempo as 10% faster (namely FAST condition) or slower (SLOW) than heart beat in a real time series, the subjects’ heart rate was successfully modulated as significantly higher in the FAST condition and lower in the SLOW condition. The timeliness regulation of this feedback system may play a key role to bring forth the music-heart beat entrainment.

2

Analysis of extracted cardiotocographic signal features to improve automated prediction of fetal outcome

Jeżewski M., Czabański R., Wróbel J., Horoba K.

Biocybernetics and Biomedical Engineering

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2010

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Vol. 30, no. 4

29-47

EN

Cardiotocographic monitoring based on automated analysis of the fetal heart rate (FHR) signal is widely used for fetal assessment. However, the conclusion generation system is still needed to improve the abnormal fetal outcome prediction. Classification of the signals according to the predicted fetal outcome by means of neural networks is presented in this paper. Multi-layer perceptron neural networks were learned through seventeen time-domain signal features extracted during computerized analysis of 749 traces from 103 patients. The analysis included estimation of the FHR baseline, detection of acceleration and deceleration patterns as well as measurement of the instantaneous FHR variability. All the traces were retrospectively verified by the real fetal outcome defined by newborn delivery data. Influence of numerical and categorical representation of the input signal features, different data sets during learning, and gestational age as additional information, were investigated. We achieved the best sensitivity and specificity for the neural networks fed with numerical input variables together with additional information on the gestational age in the categorical form.

3

The fetal heart rate estimation based on continuous ultrasonic Doppler data

Kret T., Kałużyński K.

Biocybernetics and Biomedical Engineering

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2006

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Vol. 26, no. 3

49-56

EN

Two methods to compute the fetal heart rate based on the analysis of Doppler signals obtained using continuous wave ultrasound were studied. The first uses bandpass filtering, directional signal separation and computation of the autocorrelation coefficient of the envelope of a single directional Doppler signal. The other uses discrete wavelet decomposition and reconstruction of a single directional signal with Daubechies db 10 wavelet family, with subsequent computation of the autocorrelation coefficient of the envelope of the reconstructed signal details for various scales. The results indicate that the discrete wavelet decomposition method is a suitable tool for fetal heart rate determination. It results in a more consistent fetal heart rate trace than the bandpass filtering approach.

4

Online analysis of the ultrasonic Doppler signals of the fetal motor activity in the LabVIEW environment

Kret T., Kałużyński K.

Biocybernetics and Biomedical Engineering

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2004

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Vol. 24, no. 2

41-49

EN

Fetal motor activity and the fetal heart rate are important indicators of fetal well-being. The motor activity consist of pseudobreathing movements, trunk and limb movements. These movements can be detected using the ultrasonic Doppler method. The software developed using the LabVIEW environment processes in real time Doppler signals acquired via the PC sound card. Displacements of the structures, velocities and accelerations of these displacements as well as histograms of the velocities and accelerations are computed. Spectral analysis of the chest displacement signal allows determining the rhythm of pseudobreatching movements. The autocorrelation function is used to compute the fetal heart rate. The software was tested on simulated signals and real fetal Doppler signals.