S-transform is a new time-frequency analysis method, which is deduced from short-time Fourier transform and continue Wavelet transform. It has much better performance than traditional time-frequency method. Therefore, in this paper, the basic principle of is briefly introduced and the relationships between is analyzed by theoretical derivation. According to the simulation experiments, the time-...

High-resolution Fourier transform nuclear magnetic resonance was used to observe the natural abundance (13)C spectrum of a 0.02 M solution of bovine pancreatic ribonuclease A. Peaks assignable to only three carbons were easily observed after 10 hr of signal averaging. A number of tentative assignments were made. As expected, the (13)C spectrum was appreciably richer in detail than the correspon...

We describe a Fourier Volume Rendering (FVR) algorithm for datasets that are irregularly sampled and require anisotropic (e.g., elliptical) kernels for reconstruction. We sample the continuous frequency spectrum of such datasets by computing the continuous Fourier transform of the spatial interpolation kernel which is a radially symmetric Gaussian basis function (RBF) that may be anisotropicall...

The classical method of numerically computing Fourier transforms of digitized functions in one or in -dimensions is the so-called discrete Fourier transform (DFT) efficiently implemented as fast Fourier transform (FFT) algorithms. In many cases, the DFT is not an adequate approximation to the continuous Fourier transform, and because the DFT is periodical, spectrum aliasing may occur. The metho...

continuous four hours eeg (electroencephalogram) recordings and its power spectrum analysis using fast fourier transform (fft) in urethane anesthetized male charles foster rats were performed in two groups: open brain injury and p-cpa (para-chlorophenylalanine) pretreated before brain injury, respectively, and compared with the eeg power spectrum of control rats. the eeg power spectrum analysis...

The direct Fast Fourier Transform method is very attractive for its simplicity and speed in generating multidimensional random fields. This thesis describes an efficient FFT method for generating multivariate multidimensional random fields based on the alternative spectral representation. Generation of a multivariate random field is simplified by the use of the spectral factorization function. ...

The Spectrum Sliding Analysis (SSA) is a dynamic spectrum analysis in which the next analysis interval differs from the previous one by including the next signal sample and excluding the first one from the previous analysis interval. Such a spectrum analysis is necessary for time-frequency localization of analyzed signals with given peculiarities. Using the well-known Fast Fourier Transform (FF...

in this paper we report an eco-friendly route for the synthesis of sliver nanoparticles using agaricus bisporus (white button mushroom) extract. the synthesized silver nanoparticles were confirmed and characterized by uv-visible spectrum of the aqueous solution containing silver ions showed a peak at 420 nm corresponding to the surface plasmon absorbance of silver nanoparticles. transmission el...

This paper concerns the issue of wavelet analysis of signals by continuous and discrete wavelet transforms (CWT – Continous Wavelet Transform, DWT – Discrete Wavelet Transform). The main goal of our work was to develop a program which, through the CWT and the DWT analyses, would obtain graph of time-scale changes and would transform it into the spectrum, that is a graph of frequency changes. In...