Detection of deep and hidden mineralization using the surface geochemical data is a challenging subject in the mineral exploration. In this work, a novel scenario based on the spectrum–area fractal analysis (SAFA) and the principal component analysis (PCA) has been applied to distinguish and delineate the blind and deep Mo anomaly in the Dalli Cu–Au porphyry mineralization area. The Dalli miner...

Radial sampling of the NMR time domain has recently been introduced to speed up data collection significantly. Here, we show that radially sampled data can be processed directly using Fourier transforms in polar coordinates. We present a comprehensive theoretical analysis of the discrete polar Fourier transform, and derive the consequences of its application to radially sampled data using linea...

BACKGROUND AND PURPOSE Cerebral embolism has been implicated in the development of cognitive and neurological deficits following bypass surgery. This study proposes methodology for estimating cerebral air embolus volume using transcranial Doppler sonography. METHODS Transcranial Doppler audio signals of air bubbles in the middle cerebral artery obtained from in vivo experiments were subjected...

Fourier transform infrared (FTIR) spectroscopy was used to study protein-cofactor interactions in photosystem II. The FTIR spectrum of each cofactor was measured as a difference spectrum upon its light-induced reaction. The spectrum included the bands of the protein moiety coupled to the cofactor, which were identified using selective isotopic labeling of amino acids. Analysis of these FTIR ban...

This paper presents an effort to provide a more efficient speech signal representation, which aims to be incorporated into an automatic speech recognition system. Modified cepstral coefficients, derived from a multiresolution auditory spectrum are proposed. The multiresolution spectrum was obtained using sliding single point discrete Fourier transformations. It is shown that the obtained spectr...

This paper presents an effort to provide a more efficient speech signal representation, which aims to be incorporated into an automatic speech recognition system. Modified cepstral coefficients, derived from a multiresolution auditory spectrum are proposed. The multiresolution spectrum was obtained using sliding single point discrete Fourier transformations. It is shown that the obtained spectr...

A method to rapidly estimate the Fourier power spectrum of a point distribution is presented. This method relies on a Taylor expansion of the trigonometric functions. It yields the Fourier modes from a number of FFTs, which is controlled by the order N of the expansion and by the dimension D of the system. In three dimensions, for the practical value N = 3, the number of FFTs required is 20. We...

The current status of the application of the fast Fourier transform (FFT) for the auditory evoked response was summarised under for items of importance to the auditory brain stem response (ABR) as follows. (1) Digital filter: The most common way to use FFT, which facilitates quick isolation of fast and slow components from data of the same ABR wave. In addition, the proper setting of digital fi...

The rotational signatures of methyl pyruvate as an impurity have been accidentally found and its rotational spectrum was assigned while recording the microwave spectrum of a 98% Sigma-Aldrich sample of methyl (S)-(-)-lactate with the pulsed jet Fourier transform microwave technique.