A theoretical relation is presented between the seismological Fourier amplitude spectrumand the mean squared value of the elastic response, which is defined by Gaussian distribution. Byshifting a general process to its mean value, spectrum of the mean squared value of the displacementis computed from the Fourier amplitude spectrum and the real part of the relative displacementtransfer function ...

This paper presents the Fourier and wavelet characterization of vibratio...

An adaptive enhancement procedure is presented which emphasizes continuant spectral features such as formant frequencies, by imposing frequency and amplitude continuity constraints on a short-time Fourier representation of the speech signal. At each point in the time-frequency field, the direction of maximum energy correlation is determined by the angle of a linear window at which the energy de...

The relation between Fourier spectra and spectra obtained from wavelet analysis is established. Small scale asymptotic analysis shows that the wavelet spectrum is meaningful only when the analysing wavelet has enough vanishing moments. We relate these results to regularity theorems in Besov spaces. For the analysis of innnitly regular signals, a new wavelet, with innnit number of cancellations ...

in this research calcium fluoride nanoparticles and its different amount of cerium ion dopant (5%and 10%) were prepared. the mentioned nanoparticle were studied by fourier transform infrared spectroscopy (ftir) , x-ray diffraction (xrd), absorption and photoluminescence spectra (pl) and scanning electron microscopy (sem). the xrd patterns indicate a typical cubic fluorite structure and no other...

The interpretation of Fourier spectra in the time domain is critically examined. Power density spectra defined and calculated in the time domain are compared with Fourier spectra in the frequency domain for three different types of variability: periodic signals, Markov processes and random shots. The power density spectra for a sample of neutron stars and black hole binaries are analyzed in bot...

in this research project, the nitrito nitro isomerization of [co (nh3)5no2]f2 complex has been studied. isomerization of this complex in the solid state follows a first order kinetics. the rate of isomerization at different temperatures was determined using a fourier transform lnfrared spectrophotometer. ? and ? are calculated at 298 k. the infrared, visible and ultraviolet spectra of this comp...