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Hadamard Transform Ion Mobility Spectrometry
Analytical Chemistry, 2006A detection scheme that makes use of the Hadamard transform has been employed with an atmospheric-pressure ion mobility spectrometer fitted with an electrospray ionization source. The Hadamard transform was implemented through the use of a linear-feedback shift register to produce a pseudorandom sequence of 1023 points.
Andrew W, Szumlas +2 more
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Hadamard transform imager and imaging spectrometer
Applied Optics, 1976An imager and a spectrometric imager, which achieve multiplexing by the use of binary optical encoding masks, have been built and tested. The masks are based on orthogonal, pseudorandom digital codes derived from Hadamard matrices. The spatial (and/or spectral) data are therefore obtained in the form of a Hadamard transform of the spatial (and/or ...
R D, Swift +4 more
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Denoising analysis of Hadamard transform spectrometry
Optics Letters, 2014We discuss denoising in Hadamard transform spectrometry (HTS) in terms of sensor noise, photon noise, and the sparsity of the source. An analysis based on spectra classification is proposed to estimate the signal-to-noise ratio (SNR) of both HTS and slit-based spectrometry.
Jiang, Yue +3 more
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1975
This chapter is devoted to the study of the Walsh-Hadamard transform (WHT), which is perhaps the most well-known of the nonsinusoidal orthogonal transforms. The WHT has gained prominence in various digital signal processing applications, since it can essentially be computed using additions and subtractions only. Consequently its hardware implementation
Nasir Ahmed, Kamisetty Ramamohan Rao
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This chapter is devoted to the study of the Walsh-Hadamard transform (WHT), which is perhaps the most well-known of the nonsinusoidal orthogonal transforms. The WHT has gained prominence in various digital signal processing applications, since it can essentially be computed using additions and subtractions only. Consequently its hardware implementation
Nasir Ahmed, Kamisetty Ramamohan Rao
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Decomposition of the Hadamard matrices and fast Hadamard transform
1997It is well known, that the classical algorithm of the Walsh-Hadamard fast transform needs only n log2n additions moreover n is a power of two. A problem of decomposition of Hadamard matrices of arbitrary order n, n - 0(mod4) by orthogonal (-1, +1)-vectors of size k is investigated in this paper.
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Modified Hadamard transform microchip electrophoresis
ELECTROPHORESIS, 2005AbstractSensitivity is a crucial point in the development applications for medicine or environmental samples in which the analytes are present in the nanomolar range. Besides further technical development of detection systems, the multiplex sample injection technique can be applied for enhancing the signal‐to‐noise ratio.
Renato, Guchardi, Maria A, Schwarz
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Hadamard Transform Spectroscopy
1980Fourier Transform Interferometry has become a useful tool in infrared spectroscopy. These instruments require very exacting optics and mechanical alignments which require micrometer accuracy in mirror alignments and the measurement of mirror displacement.
C. S. Bartholomew +2 more
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An improved blind watermarking method facing dual color images based on Hadamard transform
Soft Computing - A Fusion of Foundations, Methodologies and Applications, 2023Siyu Chen +3 more
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A New Fast Algorithm for Discrete Fractional Hadamard Transform
IEEE Transactions on Circuits and Systems Part 1: Regular Papers, 2019This paper proposes a new fast algorithm for calculating the discrete fractional Hadamard transform for data vectors whose size $N$ is a power of two. A direct method for the calculation of the discrete fractional Hadamard transform requires $O(N^{2})$
A. Cariow +3 more
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The Fast Fourier Transform and the Hadamard Transform
1997The discrete Fourier transform of a set of data, say x 0, x 1,…, x N -1 is given by the transform coefficients X 0, X 1,…, X N -1 by the relation $$ \left( \begin{gathered} \;\;{X_0} \hfill \\ \;\;{X_1} \hfill \\ \;\;{X_2} \hfill \\ \;\;\;\; \vdots \hfill \\ {X_{{N - 1}}} \hfill \\ \end{gathered} \right) = \left( \begin{gathered} 1\quad \quad 1 ...
R. K. Rao Yarlagadda, John E. Hershey
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