This work investigates to improve the robustness of the speaker identification systems based on a modified version of Principal Component Analysis (PCA) and Continuous Wavelet Transform (CWT). Therefore, this work proposes a robust feature extraction method based on MPCA instead of Mel Frequency Cepstral Coefficient (MFCC) that is used in the literature, which is based on converting the common ...

Laser plasma interferograms are currently analyzed by extraction of the phase-shift map with fast Fourier transform (FFT) techniques [Appl. Opt. 18, 3101 (1985)]. This methodology works well when interferograms are only marginally affected by noise and reduction of fringe visibility, but it can fail to produce accurate phase-shift maps when low-quality images are dealt with. We present a novel ...

Removal of noise is an essential step in the preprocessing of microarray images for obtaining betterquality gene expression measurements. Wavelet-based methods for denoising of images are very successful. However, for cDNA microarray images, existing methods are not as efficient because they fail to take into account linear dependencies that exist between wavelet coefficients of the red and gre...

BACKGROUND A tension pneumothorax requires immediate decompression using a needle thoracostomy. According to advanced trauma life support guidelines this procedure is performed in the second intercostal space (ICS) in the midclavicular line (MCL), using a 4.5-cm (2-inch) catheter (5-cm needle). Previous studies have shown a failure rate of up to 40% using this technique. Case reports have sugge...

A number of pixel-based image fusion algorithms (using averaging, contrast pyramids, the discrete wavelet transform and the dualtree complex wavelet transform (DT-CWT) to perform fusion) are reviewed and compared with a novel region-based image fusion method which facilitates increased flexibility with the definition of a variety of fusion rules. The DT-CWT method could dissolve an image into s...

This paper describes a method for extracting rapidly varying, superimposed amplitude-modulated and frequency-modulated signal components. The method is based upon the continuous wavelet transform (CWT) and uses a new wavelet that is a modification to the well-known Morlet wavelet to allow analysis at high resolution. In order to interpret the CWT of a signal correctly, an approximate analytic e...

We apply the continuous wavelet transform ~CWT! and a CWT spectral technique to the analysis of the time-resolved fluctuation-driven particle flux in the H-1 heliac. The results confirm that in some cases the outward radial flux reverses its direction. In addition, time-resolved frequency spectra of fluctuation signals obtained by CWT show that the dominant frequency component as a function of ...

The Last Glacial Maximum (LGM) exhibits different large-scale atmospheric conditions compared to present-day climate due to altered boundary conditions. The regional atmospheric circulation and associated precipitation patterns over Europe are characterized for the first timewith a weather typing approach (circulation weather types, CWT) for LGM paleoclimate simulations. The CWT approach is app...

The problem of diffraction of an electromagnetic wave by a thick hologram grating can be solved by the famous Kogelnik's coupled-wave theory (CWT) to a very high degree of accuracy. We confirm this finding by comparing the CWT and the exact result for a typical example and propose an explanation in terms of perturbation theory. To this end we formulate the problem of diffraction as a matrix pro...

The purpose of this study was to characterize time-frequency behavior using the Continuous Wavelet Transform (CWT) and Fast Fourier Transform (FFT) to analyze ventricular and arterial pressure signals from anesthetized mongrel dogs. Both ventricular and arterial pressure pulsations were recorded using catheter-tip manometers and the CWT was applied to these signals to obtain module coefficients...