Biomedical subjects

Huanqing Feng

Publications and source records attributed to Huanqing Feng.

3 recordsLinked to original sources

PubMed2003

[Application of complexity sequence in sleep staging based on sleep EEG data].

In this paper an approach of time-window complexity sequence is applied to sleep EEG analysis. This approach can reduce the loss of state information due to the nonstationarity of EEG signal and the unevenness of state space, and can overcome certain limitations of the complexity itself to some extent. It will help to extract the state features of EEG in different sleep stages. In addition, we preprocess EEG by adopting ICA and wavelet transform (WT). The results show that some physiological artifact in EEG can be eliminated effectively by these methods, and the sleep staging based on sleep EEG data will be more exact.

Algorithms↗

PubMed2002

[Vector propagation algorithm based ECG simulation of bundle branch block].

The simulation of excitation propagation's process in human heart is one of the main aspects of ECG forward problem. The simulation results not only are the criterion of the simulation model's precision and reliability, but also have great value in researches and diagnoses. We performed the simulation of QRST waves of complete left bundle branch block (LBBB) and right bundle branch block (RBBB) in virtue of a vector propagation algorithm (VPA), which is accurate, efficient and applicable to anisotropic computer heart models. The simulation results accord with the actual QRST wave in clinical practice.

Algorithms↗

PubMed2002

[Improvement on simulation algorithm of excitation propagation in heart modeling].

It is important to simulate the excitation propagation process of cardiac bio-electricity in the research of ECG forward problem. Traditional methods describe them with wave simulation algorithm such as LFX simulation algorithm and vector propagation algorithm etc, these methods have some problems to certain extent, due to the presence of discreteness of space and time and asymmetry of the myocardium. This paper discussed the simulation algorithm in 2-dimension space under the circumstance of layered and non-layered structure of myocardium. By calculating the theoretic values of simulating time based on Huygen's principle, we found that there were errors in LFX algorithm and no errors in vector propagation algorithm under the circumstance of non-layered structure of the myocardium, no mater what myocardium is isotropic or anisotropic. However, there exist errors from both algorithms when the myocardium has the layered structure. An improved algorithm is proposed and the simulations have been performed to examine the efficacy of the new algorithm, and the errors are reduced obviously. By increasing the number of myocardial blocks in the model, we also analyzed its influence on the error of simulation algorithm.

Algorithms↗