Results 221 to 230 of about 282,556 (263)
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ICASSP-88., International Conference on Acoustics, Speech, and Signal Processing, 2003
A novel approach to the definition of the roots of unity in the RNS (residue number system) is presented. The definition is based on a suitable polar representation of the complex residues. The resulting RNS Fourier transform provides an algorithm for performing circular convolutions characterized by flexibility in terms of length, computational cost ...
Pietro Burrascano +4 more
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A novel approach to the definition of the roots of unity in the RNS (residue number system) is presented. The definition is based on a suitable polar representation of the complex residues. The resulting RNS Fourier transform provides an algorithm for performing circular convolutions characterized by flexibility in terms of length, computational cost ...
Pietro Burrascano +4 more
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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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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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Accuracy of the Discrete Fourier Transform and the Fast Fourier Transform
SIAM Journal on Scientific Computing, 1996Accuracy 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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Randomization of the Fourier transform
Optics Letters, 2007We 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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Representation of the Fourier Transform by Fourier Series
Journal of Mathematical Imaging and Vision, 2006zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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On Eigenfunctions of the Fourier Transform
Journal of Mathematical Sciences, 2018zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Flavia Lanzara, Vladimir Maz'ya
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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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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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2018
In the previous chapter, we observed a peculiar relation between the smoothness and the rapidity of vanishing at infinity of a function f, as well as its Fourier transform \(\hat {f}\). Based upon this observation, we introduce an important function space \(\mathfrak {S}\), which is invariant under the Fourier transforms. We then proceed to \(\mathfrak
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In the previous chapter, we observed a peculiar relation between the smoothness and the rapidity of vanishing at infinity of a function f, as well as its Fourier transform \(\hat {f}\). Based upon this observation, we introduce an important function space \(\mathfrak {S}\), which is invariant under the Fourier transforms. We then proceed to \(\mathfrak
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A Remark on Fourier Transforms
Mathematical Proceedings of the Cambridge Philosophical Society, 19361. 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.
2023Gwenola Burgot, Jean-Louis Burgot
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