Results 271 to 280 of about 472,688 (313)

Fourier Transforms in VLSI

IEEE Transactions on Computers, 1983
This paper surveys nine designs for VLSI circuits that compute N-element Fourier transforms. The largest of the designs requires O(N2 log N) units of silicon area; it can start a new Fourier transform every O(log N) time units. The smallest designs have about 1/Nth of this throughput, but they require only 1/Nth as much area.
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Fourier-transform rheology

Rheologica Acta, 1998
Oscillatory shear of polymeric liquids in the non-linear regime generates higher harmonic contributions in the shear stress response. These non-linear contributions are analyzed in Fourier space with respect to the different frequencies and intensities. Simulated and experimental Fourier rheology spectra for atactic poly(propylene) melts are shown.
Wilhelm, M., Maring, D., Spiess, H.
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On Fourier-Stieltjes Transforms

Canadian Journal of Mathematics, 1955
Let be the class of bounded non-decreasing functions defined on the real line which are normalized by the conditions ϕ(− ∞) = 0 , ϕ(t + 0) = ϕ(t).Let be the class of Fourier-Stieltjes transforms of elements of i.e. the elements of and are connected by the relationwhere ϕ ∊ and Φ ∊ .It is well known, and easy to verify that this mapping from to ...
Calderón, Alberto P., Devinatz, A.
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Accuracy of the Discrete Fourier Transform and the Fast Fourier Transform

SIAM Journal on Scientific Computing, 1996
Accuracy of the discrete Fourier transform (DFT) and the fast Fourier transform (FFT) depends on the accuracy of the twiddle factors entirely. For accurate twiddle factor tables, this paper recommends to compute the sine/cosine functions with high precision arithmetic along the algorithms in terms of faster converging approximations, such as rational ...
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Representation of the Fourier Transform by Fourier Series

Journal of Mathematical Imaging and Vision, 2006
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Randomization of the Fourier transform

Optics Letters, 2007
We have investigated the multiplicity and complexity in eigenvalues of the fractional Fourier transform and found that the ambiguity of the eigenvalues may indicate randomness. We have therefore proposed a method to randomize the Fourier transform. Such a random Fourier transform can be applied in the field of image encryption and decryption.
Zhengjun, Liu, Shutian, Liu
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On Eigenfunctions of the Fourier Transform

Journal of Mathematical Sciences, 2018
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Flavia Lanzara, Vladimir Maz'ya
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Resonator Fourier transform

Seventh International Symposium on Signal Processing and Its Applications, 2003. Proceedings., 2003
This paper proposes a new discrete Fourier transform algorithm using resonator H(z) = 1/(1 + z/sup -2 /). We call this algorithm the resonator Fourier transform (RFT). In the RFT, to calculate Fourier coefficients a/sub k/ and b/sub k/ of a frequency component f/sub k/, we sample an input signal x(t) by a sampling frequency f/sub s/ = 4f/sub k/ and ...
Yoshiaki Tadokoro, Kentaro Noguchi
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A Remark on Fourier Transforms

Mathematical Proceedings of the Cambridge Philosophical Society, 1936
1. Let f(x) be a complex function belonging to LP (−∞, ∞); i.e. let f(x) be measurable, and |f(x)|p integrable, over (−∞, ∞). The functionis called the Fourier transform of f(x), if the integral on the right exists, in some sense, for almost every value of y. It is well known that, if 1 ≤ p ≤ 2, the integral (1) converges in mean, with index p′ = p/(p –
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Fourier Transforms and Fourier Transforms N.M.R.

2023
Gwenola Burgot, Jean-Louis Burgot
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