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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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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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Critical reviews in environmental science and technology, 2020 Fourier transform infrared (FTIR) spectroscopy has been extensively used in microplastic (MP) pollution research since 2004. The aim of this review is to discuss and highlight the recent advances in FTIR (spectroscopy and chemical imaging) techniques ...
S. Veerasingam +10 more
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Peak Fitting Applied to Fourier Transform Infrared and Raman Spectroscopic Analysis of Proteins
Applied Sciences, 2020 FTIR and Raman spectroscopy are often used to investigate the secondary structure of proteins. Focus is then often laid on the different features that can be distinguished in the Amide I band (1600–1700 cm−1) and, to a lesser extent, the Amide II band ...
A. Sadat, I. Joye
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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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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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Clifford algebras, Fourier transforms and quantum mechanics [PDF]
, 2012 In this review, an overview is given of several recent generalizations of the Fourier transform, related to either the Lie algebra sl_2 or the Lie superalgebra osp(1|2).
De Bie, Hendrik
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, 2020 With rapidly increased interests in biomass, diverse chemical and biological processes have been applied for biomass utilization. Fourier transform infrared (FTIR) analysis has been used for characterizing different types of biomass and their products ...
Jingshun Zhuang +4 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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Low Complexity Keystone Transform and Radon Fourier Transform Utilizing Chirp-Z Transform
IEEE Access, 2020 Keystone Transform (KT) and Radon Fourier Transform (RFT) are two popular methods proposed to overcome range migration in radars. A major concern in these methods is the computational complexity for real time operations.
Onur Culha, Yalcin Tanik
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