Results 11 to 20 of about 1,334,101 (280)
Fourier ptychography algorithm based on scaled Fourier transform
Electronics Letters, 2021 This letter discusses an alternative Fourier ptychography algorithm based on the scaled fast Fourier transform propagation. The advantage of this scheme is that it enables a zoom‐in capability of the object spectrum and complex pupil within the synthetic
Mojde Hasanzade +3 more
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On the Clifford-Fourier Transform [PDF]
International Mathematics Research Notices, 2011 For functions that take values in the Clifford algebra, we study the Clifford-Fourier transform on $R^m$ defined with a kernel function $K(x,y) := e^{\frac{i π}{2} Γ_{y}}e^{-i }$, replacing the kernel $e^{i }$ of the ordinary Fourier transform, where $Γ_{y} := - \sum_ ...
De Bie, Hendrik, Xu, Yuan
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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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Applications of Fourier transform infrared spectroscopy [PDF]
, 2012 Podeu consultar el llibre complet a: http://hdl.handle.net/2445/32166This article summarizes the basic principles of Fourier Transform Infrared Spectroscopy, with examples of methodologies and applications to different field ...
Ferrer i Felis, Núria
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Multiweighted-Type Fractional Fourier Transform: Unitarity
Fractal and Fractional, 2021 The definition of the discrete fractional Fourier transform (DFRFT) varies, and the multiweighted-type fractional Fourier transform (M-WFRFT) is its extended definition. It is not easy to prove its unitarity.
Tieyu Zhao, Yingying Chi
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Coefficient-of-Determination Fourier Transform
Computation, 2018 This algorithm is designed to perform numerical transforms to convert data from the temporal domain into the spectral domain. This algorithm obtains the spectral magnitude and phase by studying the Coefficient of Determination of a series of artificial ...
Matthew David Marko
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2022 IEEE/CVF Conference on Computer Vision and Pattern Recognition Workshops (CVPRW), 2022 Transformer architectures show spectacular performance on NLP tasks and have recently also been used for tasks such as image completion or image classification. Here we propose to use a sequential image representation, where each prefix of the complete sequence describes the whole image at reduced resolution. Using such Fourier Domain Encodings (FDEs),
Tim-Oliver Buchholz, Florian Jug
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Frequency chirped Fourier-Transform spectroscopy
Communications Physics, 2023 Fast and high-resolution Fourier transform spectrometers are indispensable for cutting-edge infrared spectroscopy. In this study, the authors employed a newly-designed fast-rotating retroreflective, broadband delay line demonstrating fast dual-comb ...
Sergej Markmann +8 more
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Fast Fourier transform revisited
Lietuvos Matematikos Rinkinys, 2015 Using FFT (fast Fourier transform), it is assumed, that some signal samples in a respective period N are updated by a sensor in real time. It is urgent for every new signal sample to have new frequency samples (f.s.).
Rimantas Pupeikis
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A Didactic and Visual Approach to the Fourier Transform
Revista Brasileira de Ensino de Física, 2023 This work provides a comprehensive derivation of the Fourier transform, with less emphasis on the mathematical rigor associated with the theory. Instead, its primary goal is to serve as a didactic resource that fosters an understanding of various ...
Daniel José Kmita +1 more
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