Results 321 to 330 of about 518,651 (330)
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2018
The frequency-domain analysis of signals and systems is efficient, in practice, due to the availability of fast algorithms for the computation of the DFT. While the DFT is defined for any length, practically efficient algorithms are available only for fast computation of the N-point DFT with N an integral power of 2.
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The frequency-domain analysis of signals and systems is efficient, in practice, due to the availability of fast algorithms for the computation of the DFT. While the DFT is defined for any length, practically efficient algorithms are available only for fast computation of the N-point DFT with N an integral power of 2.
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2014
One of the important purposes of Fourier analysis is to obtain spectra of waveforms. For that purpose, DFTs are performed on numerical sequences made from waveforms using a computer or a similar fast operational device.
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One of the important purposes of Fourier analysis is to obtain spectra of waveforms. For that purpose, DFTs are performed on numerical sequences made from waveforms using a computer or a similar fast operational device.
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Adsorption of Celecoxib on B12N12 fullerene: Spectroscopic and DFT/TD-DFT study
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2018In this study, we evaluated the effect of the Celecoxib (CXB) adsorption on the electronic and optical properties of B12N12 fullerene by using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations with the M06-2X functional and the 6-311+G** basis set.
Alireza Soltani +5 more
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Diskrete Fouriertransformation (DFT)
2000Dieser Versuch ist der erste von vier Versuchen zum Thema Frequenzbereichsdarstellung mit der diskreten Fouriertransformation (DFT). Er fuhrt Sie in die Grundlagen einer der wichtigsten und verbreitetsten Anwendungen der digitalen Signalverarbeitung ein, die Kurzzeit-Spektral-analvse Wichtige mathematischen Zusammenhange werden in der ...
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A DFT + DMFT approach for nanosystems
Journal of Physics: Condensed Matter, 2010We propose a combined density-functional-theory-dynamical-mean-field-theory (DFT + DMFT) approach for reliable inclusion of electron-electron correlation effects in nanosystems. Compared with the widely used DFT + U approach, this method has several advantages, the most important of which is that it takes into account dynamical correlation effects. The
Turkowski, Volodymyr +3 more
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2018
The 2-D DFT is presented as two sets of 1-D DFTs. Examples of the 2-D DFT are given. The formal definitions of 2-D DFT and IDFT are presented. The computation of the 2-D DFT by the row–column method is described with examples. Finally, a comprehensive coverage of the properties of the 2-D DFT is presented with examples.
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The 2-D DFT is presented as two sets of 1-D DFTs. Examples of the 2-D DFT are given. The formal definitions of 2-D DFT and IDFT are presented. The computation of the 2-D DFT by the row–column method is described with examples. Finally, a comprehensive coverage of the properties of the 2-D DFT is presented with examples.
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DFT and HF–DFT calculations of quadrupole coupling constants in molecules
Chemical Physics, 2000Abstract The efficacy of several DFT and HF–DFT methods for the calculation of 14 N quadrupole coupling constants in molecules has been investigated. Valence triple-zeta quality Pople and Dunning correlation consistent type bases were used.
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Tensor Product DFT Codes vs Standard DFT Codes
IEEE Transactions on Computers, 2019We present a new class of linear error-correcting codes taking numerical data into codewords with numerical symbols. These codes can correct large random numerical errors added to codewords. The goal is for numerical data to be protected directly as numbers whether in storage or transmission.
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Modeling the Spectra of Heavy Elements in Condensed Phase Using WFT-in-DFT and DFT-in-DFT Embedding
2012Severo Pereira Gomes, Andre +4 more
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