Results 221 to 230 of about 171,744 (267)

On narrow-band spectrum calculation by direct decimation

ICASSP '81. IEEE International Conference on Acoustics, Speech, and Signal Processing, 2005
The frequency spectrum of a long dsta sequence over a narrow band can be efficiently computed by decimating the sequence using FIR filters, and calculating an FFT on the shortened output. This method offers a low computation rate, a small storage requirement, good frequency resolution, and adjustable accuracy [1].
Maureen Quirk, Bede Liu
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One-dimensional band calculations

Journal of Physics A: Mathematical and General, 1980
Recent calculations on one-dimensional energy bands are improved remarkably by using a simple perturbation approach with D4 as the perturbation. The theoretical approach used is also relevant to the problem of including relativistic mass corrections in the Schrodinger equation.
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Methods for Calculating the Band Structure

2010
The concept of pseudopotential is presented. It is almost equivalent to the actual potential but without its strong singularity. The absence of singularity allows the solution to Schrodinger’s equation as a weighted sum of plane waves. Degenerate perturbation theory simplifies further the problem.
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Calculation of Constants for Band Spectra

Nature, 1937
IT has not infrequently proved difficult in the analysis of spectra to decide which of two or more sets of constants refer to the deepest-lying energy states: an example of this arose in my experience in the interpretation of Gale and Monk's work on the fluorine di-atom FF. Empirical methods of obtaining these numbers for ground states may therefore be
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Hückel-level Calculations on the Band Structure of Poly-AT

Nature, 1970
THE linear combination of molecular orbitals (LCMO) approximation (ref. 1 and unpublished results of R. L. F.) has been suggested as a feasible method for studying the electronic properties of random biopolymers2. In the course of some preliminary Huckel-level calculations on random polymers of adenine and thymine we found some interesting behaviour in
R L, Flurry, D, Breen
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Band-Structure Calculation Methods

1997
In this chapter we shall outline the conceptual methods usually employed to calculate the band structure of semiconductors. We start out from the adia-batic to the one-electron approximations, describe the correlation effects, and then move on to techniques for solving the Schrodinger equation—both from first principles and emperical arguments.
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Band calculation for Ce-compounds

Journal of Magnetism and Magnetic Materials, 1983
Abstract The results of self-consistent FLAPW calculations for Ce-compounds are presented. The crossover from dense Kondo to valence fluctuation in CeIn 3 under pressure is discussed. The small Fermi surfaces in CePd 3 explain the anomalous residual resistivity in this compound. The full potential effects in CeNi are examined.
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Band structure built from oligomer calculations

The Journal of Chemical Physics, 2008
A method to build accurate band structures of polymers from oligomer calculations has been developed. This method relies on systematic procedures for (i) assigning k values, (2) eliminating strongly localized molecular orbitals, and (iii) connecting bands across the entire Brillouin zone. Illustrative calculations are carried out at the HF/STO-3G level
Anna, Pomogaeva, Bernard, Kirtman, Feng Long, Gu, Yoriko, Aoki   +3 more
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Calculation of chromatographic band profiles with an implicit isotherm

Journal of Chromatography A, 1999
The numerical method for solving the mathematical model of chromatography process coupled with implicit isotherm has been proposed. The exemplary predictions of elution band profiles were performed for competitive adsorption data of 2-phenylethanol and 3-phenylpropanol on ODS-silica with methanol-water as the mobile phase.
K, Kaczmarski, D, Antos
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Band structure calculation of ZnSb

physica status solidi (b), 1978
AbstractAccurate band structures of ZnSb are obtained by the use of the empirical‐pseudopotential method. The top of the valence band is located at k = (0.93π/a, 0, 0) on the line Γ‐∑−X with symmetry ∑4 and the bottom of the conduction band is located at k = (0.47π/a, 0, 0) on the line Γ−∑−X with symmetry ∑1. The indirect energy gap is 0.60 eV.
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