Results 121 to 130 of about 10,005 (308)

Programs for high-speed Fourier, Mellin and Fourier-Bessel transforms

, 1979
Several FORTRAN program modules for performing one-dimensional and two-dimensional discrete Fourier transforms, Mellin, and Fourier-Bessel transforms are described along with programs that realize the algebra of high speed Fourier transforms on a ...
Ikhabisimov, D. K., Kolosov, B. I., Usikov, D. A., Debabov, A. S.   +3 more
core  

Using an aliasing operator and a single discrete Fourier transform to down-sample the Fresnel transform [PDF]

, 2012
In Digital Holography there are applications where computing a few samples of a wavefield is sufficient to retrieve an image of the region of interest.
María Albertina Castro Ibarra, MIGUEL OCTAVIO ARIAS ESTRADA   +1 more
core  

Solid Harmonic Wavelet Bispectrum for Image Analysis

Advanced Science, EarlyView.
The Solid Harmonic Wavelet Bispectrum (SHWB), a rotation‐ and translation‐invariant descriptor that captures higher‐order (phase) correlations in signals, is introduced. Combining wavelet scattering, bispectral analysis, and group theory, SHWB achieves interpretable, data‐efficient representations and demonstrates competitive performance across texture,
Alex Brown, Mathilda Avirett‐Mackenzie, Carolin Villforth, Georgios Exarchakis   +3 more
wiley   +1 more source

John von Neumann’s Space-Frequency Orthogonal Transforms

Mathematics
Among the invertible orthogonal transforms employed to perform the analysis and synthesis of 2D signals (especially images), the ones defined by means of John von Neumann’s cardinal sinus are extremely interesting.
Dan Stefanoiu, Janetta Culita
doaj   +1 more source

Microscale Mapping of Fiber Strain and Damage in Composite Wrinkled Laminates Using Computed Tomography Assisted Wide‐Angle X‐Ray Scattering

Advanced Science, EarlyView.
This study combines full‐field tomography with diffraction mapping to quantify radial (ε002$\varepsilon _{002}$) and axial (ε100$\varepsilon _{100}$) lattice strain in wrinkled carbon‐fiber specimens for the first time. Radial microstrain gradients (−14.5 µεMPa$\varepsilon \mathrm{MPa}$−1) are found to signal damage‐prone zones ahead of failure, which ...
Hoang Minh Luong, James Trevarthen, Igor Dolbnya, Wadwan Singhapong, Nicholas Pilato, Richard Butler, Jiraphant Srisuriyachot, Alexander J. G. Lunt   +7 more
wiley   +1 more source

A Novel Method for the Computation of the Deterministic Maximum Likelihood Estimator of Multiple Real Sinusoids

IEEE Access
In this manuscript a novel computationally efficient method for implementing the Deter- ministic Maximum Likelihood estimator of multiple superimposed real sinusoids is derived.
Pasquale Di Viesti, Jesus Selva, Giorgio M. Vitetta   +2 more
doaj   +1 more source

Comparison of Orthogonal Transforms for OFDM Communication System

Classical orthogonal frequency division (OFDM) employs fast Fourier transform (FFT) for elimination of inter-symbol interference (ISI) and expansion of time support of the transmitted signals.
Āboltiņš, Artūrs
core  

Diffraktion von Punktmengen mit struktureller Unordnung

, 2010
Matzutt KM. Diffraction of point sets with structural disorder. Bielefeld (Germany): Bielefeld University; 2010.Die vorliegende Arbeit behandelt Diffraktionseigenschaften gewisser zufälliger Strukturen.
Matzutt, Kai Miguel
core  

Single‐Atom Pt Anchoring on Self‐Doped ZrO2@G‐C3N4 Nanostructure Enables Efficient Photocatalytic Seawater Hydrogen Evolution

Advanced Science, EarlyView.
Grain‐like Zr3+‐ZrO2 and Pt single atoms are integrated into an S‐scheme Zr3+‐ZrO2@g‐C3N4 heterostructure to enable efficient visible‐light‐driven seawater hydrogen production. The combined effect of Pt single‐atom sites and the S‐scheme charge‐transfer pathway accelerates carrier separation, preserves strong redox ability, and markedly enhances ...
Hezheng Sun, Yifan Guo, Xin Yu, Yajie Tian, Feng Gao, Bin Wang, Yanting Tang, Dani S. Assi, Vellaisamy A. L. Roy   +8 more
wiley   +1 more source

The Discrete fractional fourier transform

, 2016
Cataloged from PDF version of article.
openaire   +2 more sources