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Scalable integrated two-dimensional Fourier-transform spectrometry [PDF]
Nature CommunicationsIntegrated spectrometers offer the advantages of small sizes and high portability, enabling new applications in industrial development and scientific research.
Hongnan Xu +3 more
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Discrete two dimensional Fourier transform in polar coordinates part II: numerical computation and approximation of the continuous transform [PDF]
PeerJ Computer Science, 2020 The theory of the continuous two-dimensional (2D) Fourier Transform in polar coordinates has been recently developed but no discrete counterpart exists to date.
Xueyang Yao, Natalie Baddour
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A New Discretization Scheme for the Non-Isotropic Stockwell Transform
Mathematics, 2023 To avoid the undesired angular expansion of the sampling grid in the discrete non-isotropic Stockwell transform, in this communication we propose a scale-dependent discretization scheme that controls both the radial and angular expansions in unison ...
Hari M. Srivastava +2 more
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Nonseparable two-dimensional fractional Fourier transform [PDF]
Applied Optics, 1998 Previous generalizations of the fractional Fourier transform to two dimensions assumed separable kernels. We present a nonseparable definition for the two-dimensional fractional Fourier transform that includes the separable definition as a special case. Its digital and optical implementations are presented.
Sahin, A., Kutay, M. A., Ozaktas, H. M.
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Sliding signal processing in telecommunication networks based on two-dimensional discrete Fourier transform [PDF]
ITM Web of Conferences, 2019 A method of vertical sliding processing of two-dimensional discrete signals in the spatial frequency domain is proposed — a method of fast vertically sliding two-dimensional discrete Fourier transform.
Ponomarev Vladimir +3 more
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Mathematics, 2023 In this paper, we present a novel integral transform known as the one-dimensional quaternion quadratic-phase Fourier transform (1D-QQPFT). We first define the one-dimensional quaternion quadratic-phase Fourier transform (1D-QQPFT) of integrable (and ...
Mohammad Younus Bhat +3 more
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Abstract P-23: Structural Studies of DNA-Dps Co-Crystals Formation [PDF]
International Journal of Biomedicine, 2019 Background: One of the universal mechanisms for the response of E.coli to stress is the increase of the synthesis of specific histone-like proteins that bind the DNA: Dps.
Andrey Moiseenko +7 more
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IEEE Access, 2021 The waveguide invariant is classically considered as constant in shallow water and can be utilized to estimate the source range. When the environment is variable, the error between the estimated range and the true range fluctuates and becomes unstable ...
Yuan Yao +3 more
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Arbitrary Sampling Fourier Transform and Its Applications in Magnetic Field Forward Modeling
Applied Sciences, 2022 Numerical simulation and inversion imaging are essential in geophysics exploration. Fourier transform plays a vital role in geophysical numerical simulation and inversion imaging, especially in solving partial differential equations.
Shikun Dai +4 more
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Visible–infrared two-dimensional Fourier-transform spectroscopy [PDF]
Optics Letters, 2002 We report on a new class of optical multidimensional Fourier-transform spectroscopy associated with a visible excitation-infrared emission configuration, in which the emitted field results from second-order optical nonlinearities. This configuration is demonstrated on a phase-matched sample of known nonlinear response by coherent measurement of the mid-
Belabas, Nadia, Joffre, Manuel
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