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WaveShrink plays pivotal role in analysis of complex bio signals. Wavelet analysis and WaveShrink are the established techniques of statistical research which have to be blended with the analysis of bio signals to provide a high degree of correlation between the desired signal and the observed signal. The multifaceted shrinkage function will obtain lurid responses to the signal perturbed to a very...
Methodologies of deriving phase information from pulsatile intracranial pressure (ICP) signal and characterizing its phase coordination with electrocardiogram (ECG) signal were discussed. The application of ICP phase characterization methods to data from several clinical contexts showed that 1) Unstable periods of ICP were associated with a decreased ICP phase coordination with ECG; 2) Surgical treatment...
While biosignal analysis has been a mainstay in many medical applications for a number of decades, notably in cardiology, problems remain in the analysis of high volume data and in comparison among time series. Effective comparisons can determine if the state of a particular patient has changed significantly. These comparisons are useful in both long-term and short-term monitoring. Methods will vary...
Studies suggest that obstructive sleep apnea syndrome (OSAS) is causally related to abnormal cardiovascular autonomic control in adults, but this has not been established in pediatric OSAS. The goal of this study was to quantify autonomic system dysfunction, as manifested by cardiovascular response abnormalities, in children with OSAS. During wakefulness, we continuously measured the ECG, arterial...
A software approach has been developed for detecting electrocautery noise in the electrocardiogram (ECG) using a wavelet decomposition of the signal. With this approach, a clinical monitoring expert system can be forewarned of potential artefacts in trend values derived from the ECG, allowing it to proceed with caution when making decisions based on these trends. In 15 operations spanning 38.5 hours...
Recently we have studied the effects of extremely low frequency pulsed electromagnetic fields (ELF-PEMF) on the human biosignals. Electrocardiogram (ECG) and electroencephalogram (EEG) of seventeen healthy volunteers before and after the electromagnetic (EMF) exposure were recorded and analyzed. The root mean square (RMS) values of the recoded data were considered as comparison criteria. EEG results...
We investigate a new model for the cardiac system. It embodies the main features of cardiac activity with great flexibility. It can be tuned to suit different cell types, and scaled up or down to represent either a single cell, an aggregate, or whole tissue. We demonstrate its use in the generation of a clinically realistic electrocardiogram (ECG) and other dynamical behaviours such as spiral waves...
This paper proposes to use the pulse transit time variability (PTTV) as an indicator of the variability in hemodynamics and studies its correlation with other cardiovascular variabilities, especially the blood pressure variability (BPV), which receives increasing attentions as an independent indicator of autonomic regulation and abnormalities in cardiovascular system. Continuous blood pressure (BP),...
This study investigates the possibility of using the normalized time-domain features of electrocardiogram (ECG) for improving the capability of human identification. For this purpose, we measured lead-1 rest ECG (normal heart rate) and physically active one (fast heart rate) from the pre-selected group. The characteristic points on the ECG waveform, P, QRS, T are extracted in terms of its time location...
In this paper, we proposed a heartbeat classification algorithm based on linear discriminant analysis and artificial neural network. For the input of classifier, we extracted 275 input features from the first derivative signal of ECG signal and RR interval information and it was reduced to be 6 by LDA. To evaluate the performance of the proposed algorithm, we compared the result of the proposed algorithm...
Electrocardiographic (ECG) analysis plays an important role in safety assessment during new drug development and in clinical diagnosis. The pre-processing of ECG analysis consists of low-frequency baseline wander (BW) correction and high-frequency artifact noise reduction from the raw ECG. We present approaches for BW correction and de-noising based on discrete wavelet transformation (DWT). We estimate...
Spectral analysis was carried out on the R-wave attenuation (RWA) trend and heart rate variability (HRV) series, derived from the polysomnographic electrocardiogram (ECG) of the subjects with and without Cheyne Stokes breathing. Nocturnal polysomnography was performed on 16 normal subjects and 7 subjects with Cheyne Stokes breathing (CSB) patients. The polysomnographic ECG data was divided into fifteen...
The impact of colour and light conditions on our emotional and physical health and wellbeing is gaining greater importance in our urban societies. While large resources are allocated for well designed buildings with the right choice of colour and lighting conditions, there are little scientific evidence that supports these choices. The aim of this research was to determine the impact of different...
A kind of remote monitoring system on heart sound is constructed, which can tele-monitor ECG and PCG. The system integrates embedded Internet technology and wireless technology. As it can send ECG and PCG by Internet, it realizes real-time recording and monitoring of physiology parameter of patients at low cost and both at home and in hospital, and it also can be used for analysis for computer or...
In the nearest future a lot of post-operative treatment and health monitoring is going to be performed in people's homes instead of in hospital. The increasing number of elderly people in the developed countries and the need for more advanced medical treatment and equipment in conjunction with economical demands will force the development of more cost-effective solutions. The equipment used must be...
In this paper, we propose a measuring device implementation to measure ECG, 50 KHz BIA for getting BIA/respiration, and 10~50 Hz GSR for measuring electrical characteristics of skin. To this end, BIA signal is separated by line filter and high impedance element and the interference between signals could be minimized by switching in time domain to separate ECG and GSR signals having the similar frequency...
Noise always influences on the result of signal-detection, therefore it is a hot topic to detect signal under the low signal-to-noise ratio (SNR) in current detection field. However, it is an intractable problem of signal-detection to extract weak signal under a high noisy environment. Adaptation filter provides a simple and useful way to detect signal. Through measuring and studying, it is possible...
An algorithm using wavelets and Kalman filtering method has been developed for QRS detection. The algorithm takes following steps: i) We use a RLS adaptive algorithm to establish a model of the electrocardiogram. Thus the algorithm can change its own model according to the change of the electrocardiogram, ii) Based on the model established in stage i), we combined the wavelet and Kalman algorithm,...
The present study proposes a new stress evaluation technique using the photoplethysmogram (PTG). Heart rate variability (HRV) is often used to evaluate mental stress. HRV can be measured from an electrocardiogram (ECG). The frequency variability of HRV and mental stress response are related. PTG also indicates changes in emotional response. PTG can easily be measured without body surface electrodes...
The goal of our research is try to explain the electrophysiological mechanisms of alternation in T-wave of ECG in ultrahigh static magnetic field (SMF). The magneto-hydrodynamics model study shows that ultrahigh SMF can induce reduction in the volume flow rate of the blood in human aorta more than 10%, thus may lead to anoxia condition of acute ischemia. Using an ionic-based theoretical model of the...
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