in exploration seismology quality factor is widely used as a seismic attribute to identify anomalies related to attenuation, especially those caused by hydrocarbon. previous studies have indicated that seismic energy loss known as attenuation is greater for high frequency components of seismic data compared to the low frequency components. here the continuous wavelet transform is used to study ...

.................................................................................................................................. iii ACKNOWLEDGEMENTS ............................................................................................................ v TABLE OF CONTENTS ............................................................................................................... vi L...

The noninvasive peripheral oxygen saturation (SpO2) and the pulse rate can be extracted from photoplethysmography (PPG) signals. However, the accuracy of the extraction is directly affected by the quality of the signal obtained and the peak of the signal identified; therefore, a hybrid wavelet-based method is proposed in this study. Firstly, we suppressed the partial motion artifacts and correc...

The non-invasive pulse-oximeter is a crucial parameter in continuous monitoring systems. It plays a vital role from admission of the patient to surgeries with general anaesthesia. The paper proposes the application of wavelet transform to delineate the raw plethysmograph signals obtained from basic portable and mobile-powered electronic hardware. The paper primarily focuses on finding peaks and...

The nonlinear dynamical system which models the axon impulse activity is studied through the analysis of the wavelet coefficients. A system with a high pulse source is analyzed in dependence of the amplitude. It is shown that there exists a critical value of the amplitude, and a catastrophe above it. This value is easily detected by the large values of the wavelet coefficients.

In this paper, we first investigate the power spectral densities (PSD) of bipolar modulated Direct Sequence Ultra Wide Band (DS-UWB) signals using various pulse shapes under the FCC UWB emission mask. Considered pulse shapes are the first five derivatives of the Gauss pulse (p1, p2, p3, p4 and p5), the first four orthogonal modified Hermite waveforms, and Daubechies wavelets (db-q). It is obser...

Common-mode voltage (CMV) generated by the inverter causes motor bearing failures in multiphase drives.On the other hand, presence of undesired z-component currents in six-phase induction machine (SPIM) leads to extra current losses and have to be considered in pulse width modulation (PWM) techniques. In this paper, it is shown that the presence of z-component currents and CMV in six phase driv...

By using the wavelet transform, we develop a hierarchical planar curve descriptor that decomposes a curve into components of different scales so that the coarsest scale components carry the global approximation information while the finer scale components contain the local detailed information. We show that the wavelet descriptor has many desirable properties such as multiresolution representat...