Deep web provides tremendous structured data with high quality. In order to retrieve deep web data, one important task is to classify the domains of deep web automatically. In this paper, an approach based on domain feature text (DFT) is presented to classify the deep web. In the phase of DFT selection, a semantic abstract method based on ontology knowledge and a quantitative criteria for DFT s...

A review of the literature about calculating the adsorption properties of arsenic onto mineral models using density functional theory (DFT) is presented. Furthermore, this work presents DFT results that show the effect of model charge, hydration, oxidation state, and DFT method on the structures and adsorption energies for As and As onto Fe-(oxyhydr)oxide cluster models. Calculated interatomic ...

A method is presented for computing an orthonormal set of eigenvectors for the discrete Fourier transform (DFT). The technique is based on a detailed analysis of the eigenstructure of a special matrix which commutes with the DFT. It is also shown how fractional powers of the DFT can be efficiently computed, and possible applications to multiplexing and transform coding are suggested. T

In this study the molecular geometries, experimental vibrational and electronic absorption spectra and quantum chemical calculations of free dimethyl phenylphosphonite, (C8H11PO2), (with synonym, dimethoxyphenylphosphine or phenyldimethoxyphosphine) (Abbreviated as DMPP) and its [Cd(DMPP)].Cl2.H2O metal halide complex have been investigated by using elemental analysis, FT-IR, micro-Raman and UV...

First-principles density functional theory (DFT) is used to study the solid-state modifications of carbon dioxide up to pressures of 60 GPa. All known molecular CO2 structures are investigated in this pressure range, as well as three non-molecular modifications. To account for long-range van der Waals interactions, the dispersion corrected DFT method developed by Grimme and co-workers (DFT-D3) ...

Large scale Density Functional Theory (DFT) based electronic structure calculations are highly time consuming and scale poorly with system size. While semi-empirical approximations to DFT result in a reduction in computational time versus ab initio DFT, creating such approximations involves significant manual intervention and is highly inefficient for high-throughput electronic structure screen...

Fractional Fourier transform (FRFT) is a generalization of Fourier transform, and it indicates a rotation of signal in the time-frequency plane[l). The FRFT has been widely successfully used in the many areas[l][2]. Because of the importance of FRFT, discrete fractional Fourier transform (DFRFT) becomes an important issue in recent years[3][4] [5][6]. In the development of DFRFT, the DFRFT has ...

Quinolines are the essence of many natural products, drugs and were found in synthetic compounds. Quinoline derivatives containing a quinoline ring used variety biological pharmaceutical activities, e.g. anticancer, antibacterial, antifungal, antiplasmodial, antihistamine, antimalarial antituberculosis. In this study, 2-Chloro-7-Methylquinoline-3-Carbaldehyde (ClMQC) molecule, which is derivati...

In this paper, an approach is proposed to improve the numerical precision at the sound field simulation by the finite-difference time-domain (FDTD) method. The FDTD method is a numerical solution for the wave equation, proposed by R. Courant. Although it has achieved to simulate wave propagation by numerical solution for the wave equation, it causes numerical dispersions due to their approximat...

Density Functional Theory (DFT) calculations with computational effort which increases linearly with the number of atoms (linear-scaling DFT) have been successfully developed for insulators, taking advantage of the exponential decay of the one-particle density matrix. For metallic systems, the density matrix is also expected to decay exponentially at finite electronic temperature and linear-sca...