Dispersive Fourier transformation (DFT) maps the broadband spectrum of an ultrashort optical pulse into a time stretched waveform with its intensity profile mirroring the spectrum using chromatic dispersion. Owing to its capability of continuous pulse-by-pulse spectroscopic measurement and manipulation, DFT has become an emerging technique for ultrafast signal generation and processing, and hig...

in the present work, dft calculations are employed to obtain the optimized structures of 4-acyl pyrazolone tautomers (19 tautomers) using b3lyp/6-311++g** calculations. inaddition, molecular parameters, ir frequencies and relative energies are extracted for alltautomers. the existence of aromatic ring, keto tautomer (versus enol tautomer), n-h bond(versus c-h bond) and c=n double bond (versus n...

density functional (dft) calculations at m05-2x/aug-cc-pvdz level were used to analyze the interactions between dimethyl sulfoxide (dmso) dimers. the structures obtained have been analyzed with the atoms in molecules (aims) and natural bond orbital (nbo) methodologies. four minima were located on the potential energy surface of the dimers. three types of interactions are observed, ch•••o, ch•••...

in the present work, the electronic properties of titanium were studied in three phases of α, β and ω using the density function theory (dft). the full potential augmented plane wave plus local orbital (flapw+lo) method was applied using the generalized gradient approximation. the calculated total energies showed that omega phase was more stable than the two other phases. the largest electrical...

In this paper an estimator for speech enhancement based on Laplacian Mixture Model has been proposed. The proposed method, estimates the complex DFT coefficients of clean speech from noisy speech using the MMSE  estimator, when the clean speech DFT coefficients are supposed mixture of Laplacians and the DFT coefficients of  noise are assumed zero-mean Gaussian distribution. Furthermore, the MMS...

BACKGROUND The ideal programming of the implantable cardioverter defibrillator (ICD) shock energy should be at least 10J above the defibrillation threshold (DFT), requiring alternative techniques when the DFT is elevated. OBJECTIVE To assess the clinical behavior of ICD patients with DFT>25J and the efficacy of the chosen therapy. METHODS Patients who had undergone ICD implantation between ...

Density functional theory (DFT) embedding provides a formally exact framework for interfacing correlated wave-function theory (WFT) methods with lower-level descriptions of electronic structure. Here, we report techniques to improve the accuracy and stability of WFT-in-DFT embedding calculations. In particular, we develop spin-dependent embedding potentials in both restricted and unrestricted o...

BACKGROUND AND AIMS Childhood obesity has been associated with high refined sugar intake. The relationship between sucrose intake and development of dental caries has been established. The aim of this study was to determine the association between age-specific body mass index (BMI-for-age) and dental caries in children. MATERIALS AND METHODS In this cross-sectional study a total of 1003 child...

We give a detailed study of the discrete Fourier transform (DFT) of r-even arithmetic functions, which form a subspace of the space of r-periodic arithmetic functions. We consider the DFT of sequences of r-even functions, their mean values and Dirichlet series. Our results generalize properties of the Ramanujan sum. We show that some known properties of r-even functions and of the Ramanujan sum...

A. Table of contents by sections: 1. Abstract (you’re reading this now) 2. Summary of the DFT (How do I do the homework?) 3. Review of continuous-time Fourier series 4. Bandlimited signals and finite Fourier series 5. Sampling theorem for periodic signals 6. Review of quirks of discrete-time frequency 7. Orthogonality and its significance 8. Discrete Fourier Transform (DFT) 9. Use of DFT to com...