Comparison of Wavelet Transform Modulus Maxima and Multifractal Detrended Fluctuation Analysis of Heart Rate in Patients with Systolic Dysfunction of Left Ventricle

Gałąska, Rafał; Makowiec, Danuta; Dudkowska, A; Koprowski, Andrzej; Chlebus, Krzysztof; Wdowczyk-Szulc, Joanna; Rynkiewicz, Andrzej

doi:10.1111/j.1542-474x.2008.00215.x

Cited by 43 publications

(41 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The third method is based on the wavelet transformations (WTs), and has been shown to be a very useful tool for the analysis of a wide variety of nonstationary series. The WTs have been used in many disciplines, ranging from mathematics (Narasimha and Bhattacharyya 2010 and references therein), to environmental science (Heidari Nasab et al 2004;Souza Echer et al 2008), medicine (van Milligen et al 1995;Galaska et al 2008) and geophysics (Grinsted et al 2004;Maraun and Kurths 2004;Ge 2008); for a review see Sahimi (2003).…”

Section: Introductionmentioning

confidence: 99%

Analysis of Cross Correlations Between Well Logs of Hydrocarbon Reservoirs

et al. 2011

View full text Add to dashboard Cite

We carry out a series of cross-correlation analysis of raw well-log data, in order to study the possible connection between natural gamma ray (GR) logs and other types of well logs, such as neutron porosity (NPHI), sonic transient time (denoted usually by DT), and bulk density (RHOB) of oil and gas reservoirs. Three distinct, but complementary, methods are used to analyze the cross correlations, namely, the multifractal detrended cross-correlation analysis (MF-DXA), the so-called Q cc (m) test in conjunction with the statistical test-the χ 2 (m) distribution-and the cross-wavelet transform (XWT) and wavelet coherency. The Q cc (m) test and MF-DXA are used to identify and quantify the strength of long-range cross correlations between the porosities derived based on the NPHI, DT, and RHOB logs on the one hand, and the GR log that is indicative of the presence of clay minerals in reservoir rocks, on the other hand. The Q cc (m) test describes qualitatively the presence of such cross correlations between the porosity and GR logs. Analysis by the MF-DXA method also indicates that the various porosity logs, the GR log, and the cross correlations between them are multifractal, hence confirming the long-range nature of the correlations. The results are confirmed further by the XWT, and indicate that the porosities estimated based on the NPHI logs are only weakly, if at all, affected by the natural GR radioactivity of reservoir rock and are, therefore, most reliable. The effect of length scale on the correlations and cross correlations 123 446 H. Dashtian et al. was studied in detail. It is shown that such correlations exist at all length scales, and that they are of multifractal type that must be characterized by a spectrum of exponents.

show abstract

Section: Introductionmentioning

confidence: 99%

Analysis of Cross Correlations Between Well Logs of Hydrocarbon Reservoirs

et al. 2011

View full text Add to dashboard Cite

show abstract

“…cardiac transplantation vs. ventricular tachycardia), evidencing the ANS influences on the cardiac rhythm control. On the other hand, Galaska et al [15] found that the generalized Hurst exponents had a significantly larger range of exponents and the global Hurst exponent was significantly lower in healthy subjects in comparison to patients with systolic dysfunction of left ventricle, when they used MF-DFA algorithm.…”

Section: Discussionmentioning

confidence: 99%

“…The width of f(α) is defined by the index ∆α = α max − α min , which has been used in several studies to evaluate the multifractality degree of f(α) in heart rate dynamics corresponding to healthy and pathologic subjects [9], [10], [14], [15]. Also, the value of the singularity exponent α m for which f(α) is maximum was considered as an index.…”

Section: B Multifractal Analysismentioning

confidence: 99%

Multifractal characterization of the autonomous nervous system during prolonged coronary artery occlusion

Magrans

Gomis

Caminal

et al. 2009

2009 Annual International Conference of the IEEE Engineering in Medicine and Biology Society

View full text Add to dashboard Cite

Abstract-We assess the autonomic nervous system response during prolonged percutaneous transluminal coronary angioplasty (PTCA) by heart rate variability analysis using multifractal indices. These indices are also used to evaluate the effects of the PTCA at different arteries. The indices augmented significantly during transient ischemia and reperfusion periods indicating an increase of multifractal degree and a decrease of the long-range dependence on heartbeat fluctuations. This indicates that significant multifractal complex reactions of autonomic control of the heart rate occurred during coronary artery occlusions.

show abstract

“…Finally for "DBC-mes" measure, the results are better than the three other ones, the spectrum width dα is equal to that of the theoretical spectrum ( Figure 7). This result is interesting, because the spectrum width can be used like a discriminative value between two populations [6,17]. Therefore, it is important to have an exact approximation.…”

Section: D Casementioning

confidence: 99%