Results 21 to 30 of about 115,549 (311)
q-Fourier Transform and its Inversion-Problem [PDF]
Milan Journal of Mathematics, 2012 Tsallis' q-Fourier transform is not generally one-to-one. It is shown here that, if we eliminate the requirement that $q$ be fixed, and let it instead "float", a simple extension of the $F_q-$definition, this procedure restores the one-to-one character.
Plastino, Ángel Luis +1 more
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Mixed problem for the singular partial differential equation of parabolic type
Karpatsʹkì Matematičnì Publìkacìï, 2018 The scheme for solving of a mixed problem is proposed for a differential equation \[a(x)\frac{\partial T}{\partial \tau}= \frac{\partial}{\partial x} \left(c(x)\frac{\partial T}{\partial x}\right) -g(x)\, T\] with coefficients $a(x)$, $g(x)$ that are the
O.V. Makhnei
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Finite element modeling of integral viscoelastic properties of textile composites [PDF]
E3S Web of Conferences, 2023 The problem of modeling the effective integral viscoelastic properties of unidirectional composite materials is considered. To calculate the integral properties of viscoelasticity, the Fourier transform and the inverse Fourier transform are used, as well
Dimitrienko Yu. +5 more
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Whole space case for solution formula of Korteweg type fluid motion in R3 [PDF]
E3S Web of ConferencesIn this paper we consider the solution formula of linearized diffusive capillary model of Korteweg type without surface tension in three-dimensional Euclidean space ℝ3 using Fourier transform.
Bagus Suhada Dede +5 more
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The problem of trigonometric Fourier series multipliers of classes in λp,q spaces
Қарағанды университетінің хабаршысы. Математика сериясы, 2020 In this article, we consider weighted spaces of numerical sequences λp,q, which are defined as sets of sequences a = {ak}∞k=1, for which the norm ||a||λp,q := (∞Σk=1|ak|qkq/p −1)1/q < ∞ is finite. In the case of non-increasing sequences, the norm of the
A. Bakhyt, N.T. Tleukhanova
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On an Extremal Problem in Fourier Series [PDF]
Canadian Mathematical Bulletin, 1960 Let f(x) be a bounded odd function, - π < x < π, |f(X)| ≤ 1, with non-negative Fourier coefficients bk, k = 1,2, ….Otto Szász [l] proved anew the existence of a bounded set of numbers {βn}, n = 1,2,…, such thatwhere βn is the smallest constant satisfying the above inequality and added that 2/π ≤ βn ≤ 4/π. He pointed out [1, p.
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Mathematics, 2022 In this research, we investigate an optimal control problem governed by elliptic PDEs with Dirichlet boundary conditions on complex connected domains, which can be utilized to model the cooling process of concrete dam pouring.
Mengya Su, Liuqing Xie, Zhiyue Zhang
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A signal theory approach to support vector classification: the sinc kernel [PDF]
, 2009 Fourier-based regularisation is considered for the support vector machine classification problem over absolutely integrable loss functions. By invoking the modest assumption that the decision function belongs to a Paley–Wiener space, it is shown that the
Nelso, James D.B. +3 more
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Journal of Mathematics, 2023 In this paper, we work on the Cauchy problem of the three-dimensional micropolar fluid equations. For small initial data, in the variable-exponent Fourier–Besov spaces, we achieve the global well-posedness result.
Muhammad Zainul Abidin +3 more
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Some inverse problems of Fourier optics
Contemporary Mathematics. Fundamental Directions, 2023 We consider a general formulation of the problem of signal reconstruction from incomplete a priori information about it and measurements of the intensity of its Fourier transform. Some special cases are studied when a priori information is the even or odd part of the signal, as well as the real or imaginary part of the signal.
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