Results 11 to 20 of about 66,276 (316)
Total retardance measurements based on the complex Fourier coefficients for the rotating polarizer analyzer system [PDF]
Heliyon, 2023 We propose a demodulation algorithm based on the calculus of the complex Fourier coefficients; we used a dual rotating polarizer-analyzer polarimeter to show the feasibility of our proposal.
Geliztle A. Parra-Escamilla +3 more
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Random rearrangements of Fourier coefficients [PDF]
The Annals of Mathematics, 1976 In [2] and [3] Hardy and Littlewood gave (1) necessary and sufficient conditions that numbers on, -0 should be, for every variation of their arguments and arrangement, the Fourier coefficients of a function in LP (2 < p < c), and (2) necessary and sufficient conditions that such numbers should be, for some variation of their arguments and arrangement ...
Daniel M. Oberlin
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On the behavior of Fourier coefficients [PDF]
Proceedings of the American Mathematical Society, 1954 We write (3) 0(t) = f(x + t) f(x t), A(t) = f(x + t) f(x t) -1, where I is a finite number. It is known' that if &(t)-*O as t-0O, then the sequence { nBn(x) } is summable (C, r), r> 1, to the value 1/r, but not necessarily summable (C, 1). It is also known2 that with the same hypothesis the sequence {nBn(x) } is summable by the first logarithmic mean ...
R. Mohanty, M. Nanda
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Fourier coefficients for Laguerre–Sobolev type orthogonal polynomials [PDF]
Arab Journal of Mathematical Sciences, 2023 Purpose – In this paper, the authors take the first step in the study of constructive methods by using Sobolev polynomials. Design/methodology/approach – To do that, the authors use the connection formulas between Sobolev polynomials and classical ...
Alejandro Molano
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Journal of Optimization, Differential Equations and Their Applications, 2023 For the problem of optimal control of a parabolic-hyperbolic process with nonlocal point boundary conditions, an explicit form of the solution is obtained in the form of formal series according to the system of eigenfunctions, which are generated by the ...
Volodymyr O. Kapustyan +3 more
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Alternative Method to Estimate the Fourier Expansions and Its Rate of Change
Mathematics, 2022 This paper presents a methodology to obtain the Fourier coefficients (FCs) and the derivative Fourier coefficients (DFCs) from an input signal. Based on the Taylor series that approximates the input signal into a trigonometric signal model through the ...
Johnny Rodríguez-Maldonado +2 more
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Coefficients of multiple Fourier-Haar series and variational modulus of continuity
Қарағанды университетінің хабаршысы. Математика сериясы, 2023 In this paper, we introduce the concept of a variational modulus of continuity for functions of several variables, give an estimate for the sum of the coefficients of a multiple Fourier-Haar series in terms of the variational modulus of continuity, and ...
T.B. Akhazhanov +3 more
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Scientific Reports, 2022 Chirps are familiar in nature, have a built-in resistance to noise and interference, and are connected to a wide range of highly oscillatory processes.
Omar T. Bafakeeh +9 more
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On the Combination of Harmonics and Polynoms in Econometric Modeling of RUB/AZN Exchange Rate
Статистика и экономика, 2022 Conducting a combinational polynomial and spectral analysis of time series formed on the basis of daily observations of changes in the RUB/AZN exchange rate with pronounced fluctuations for the period 11.05.2017- 02.11.2018 based on computer econometric ...
L. M. Mamedova
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ANALYTIC FUNCTIONS OF INFINITE ORDER IN HALF-PLANE
Проблемы анализа, 2022 J. B. Meles (1979) considered entire functions with zeros restricted to a finite number of rays. In particular, it was proved that if 𝑓 is an entire function of infinite order with zeros restricted to a finite number of rays, then its lower order ...
K. G. Malyutin +2 more
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