Discrete Fourier transform and permutations [PDF]
Bulletin of the Polish Academy of Sciences: Technical Sciences, 2019 It is well known that the magnitudes of the coefficients of the discrete Fourier transform (DFT) are invariant under certain operations on the input data. In this paper, the effects of rearranging the elements of an input data on its DFT are studied.
S. Hui, S.H. Żak
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Two-point boundary value problem for a partial differential equation in spaces of periodic functions
Математичні Студії, 2020 We investigate the two-point in time boundary value problem for the partial differential equations of the second-order with one spatial variable and constant coefficients. The problem is considered in in the spaces of functions which Fourier coefficients
V.S. Ilkiv +3 more
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Crystallite size distribution and dislocation structure determined by diffraction profile analysis: principles and practical application to cubic and hexagonal crystals [PDF]
, 2001 Two different methods of diffraction profile analysis are presented. In the first, the breadths and the first few Fourier coefficients of diffraction profiles are analysed by modified Williamson-Hall and Warren-Averbach procedures. A simple and pragmatic
Borbély, A. +3 more
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Transformations of Fourier coefficients [PDF]
Proceedings of the American Mathematical Society, 1952 Introduction. In 1923 M. Fekete [2]2 introduced the concept of factor sequences that left invariant the class of a Fourier series. That is, Fekete investigated the conditions to which a sequence of constants (X„) must be subjected in order that (X„a„, X„i„) be Fourier coefficients of a function of the same class, K, as that of the function determined ...
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Asymptotic behavior of entire functions of improved regular growth in the metric of $L^p[0, 2\pi]$
Karpatsʹkì Matematičnì Publìkacìï, 2013 We describe an asymptotic behavior of entire functions of improved regular growth with zeros on a finite system of rays in the metric of $L^p[0, 2\pi]$.
R.V. Khats’
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Karpatsʹkì Matematičnì Publìkacìï, 2020 Let $f$ be an entire function of order $\rho\in (0,+\infty)$ with zeros on a finite system of rays $\{z: \arg z=\psi_{j}\}$, $j\in\{1,\ldots,m\}$, $0\le ...
R.V. Khats'
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A method to derive Fourier–wavelet spectra for the characterization of global-scale waves in the mesosphere and lower thermosphere and its MATLAB and Python software (fourierwavelet v1.1) [PDF]
Geoscientific Model Development, 2023 This paper describes a simple method for characterizing global-scale waves in the mesosphere and lower thermosphere (MLT), such as tides and traveling planetary waves, using uniformly gridded two-dimensional longitude–time data.
Y. Yamazaki
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Hyperbolic Fourier coefficients of Poincaré series [PDF]
The Ramanujan Journal, 2016 38 pages, typos ...
O'Sullivan, Cormac, Taylor, Karen
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Some Fourier-Stieltjes Coefficients Revisited [PDF]
Proceedings of the American Mathematical Society, 1989 We give a new proof of a result of R. Salem: The Fourier-Stieltjes coefficients of certain strictly increasing singular functions do not vanish at infinity.
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Generalized Fourier coefficients of multiplicative functions
, 2017 We introduce and analyse a general class of not necessarily bounded multiplicative functions, examples of which include the function $n \mapsto \delta^{\omega (n)}$, where $\delta \neq 0$ and where $\omega$ counts the number of distinct prime factors of $
Matthiesen, Lilian
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