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Technique For Video Compression By Projection Onto Convex Sets, P. Santago, Sarah A. Rajala
Technique For Video Compression By Projection Onto Convex Sets, P. Santago, Sarah A. Rajala
Sarah A. Rajala
This paper describes a video compression technique which utilizes the alternating projection theorem for convex sets. The image to be transmitted is determined to be in certain convex sets and parameters defining these sets are sent. The receiver can then use the method of successive projections to locate an image which is in the intersection of the sets. If the intersection is small then the image determined should be close to the desired image. The coder can be made more robust by easily adding additional convex sets or using it in conjunction with other coding schemes such as motion compensation.
Fast Method For Calculating The Self-Consistent Electronic Structure Of Random Alloys, Duane D. Johnson, F. J. Pinski, G. M. Stocks
Fast Method For Calculating The Self-Consistent Electronic Structure Of Random Alloys, Duane D. Johnson, F. J. Pinski, G. M. Stocks
Duane D. Johnson
We describe a computationally efficient method for performing self-consistent-field calculations of the electronic structure of random solid-solution alloys within the multiple-scattering coherent-potential-approximation formalism (KKR-CPA). We utilize a cluster method for solving the KKR-CPA equations and integrate along a contour in the complex-energy plane to reconstruct the single-site electronic densities.
The Electronic Properties Of Ar And Xe Under Pressure, Richard Alan Lesar
The Electronic Properties Of Ar And Xe Under Pressure, Richard Alan Lesar
Richard Alan Lesar
A simple model for calculating ground- and excited-state properties of molecular and rare-gas crystals is presented. The electrons are considered to be tightly bound to their molecular or atomic sites and the effects of the crystal potential, calculated with local-density funcationals, are treated as a perturbation of the molecules or atoms. Results for Ar to 500 kbar show that the ground-state atoms compress as the pressure is increased and that there is a gradual increase in excition energies. Preliminary results on ground-state Xe to 1.5 Mbar show that, to about 1 Mbar, the electronic distributions of the Xe atoms compress, …
Electron-Gas Plus Damped-Dispersion Model For Intermolecular Forces. The Rare-Gas And H,-He, H,-Ne, And H,-Ar Potentials, Richard Alan Lesar
Electron-Gas Plus Damped-Dispersion Model For Intermolecular Forces. The Rare-Gas And H,-He, H,-Ne, And H,-Ar Potentials, Richard Alan Lesar
Richard Alan Lesar
The modified Gordon-Kim (MGK) electron-gas model for the calculation of the short-range repulsive interactions between closed-shell atoms and molecules is used with a damped-dispersion term of a form suggested by Hepburn et al. to calculate the intermolecular potentials between the rare-gas atoms and H,-He, H2-Ne, and H,-Ar. The damping function for the dispersion energies is found by comparison with the experimental Ar-Ar potential and is then used without change for all other interactions. Except for interactions involving Ne atoms, the results for the atom-atom interactions are uniformly quite good, with an average deviation from experiment in the position of the …
An Evaluation Of The Directed Flow Graph Methodology, Wesley E. Snyder, Sarah A. Rajala
An Evaluation Of The Directed Flow Graph Methodology, Wesley E. Snyder, Sarah A. Rajala
Sarah A. Rajala
The purpose of this project was to evaluate the applicability of the Directed Graph Methodology (DGM) to the design and analysis of special purpose image and signal processing hardware. To this end, a special purpose image processing system was designed and described using DGM. The design, suitable for VLSI, implements an innovative region labeling technique. The utility of DGM was evaluated using this design.
Improved Electron‐Gas Model Calculations Of Solid N2 To 10 Gpa, Richard Alan Lesar
Improved Electron‐Gas Model Calculations Of Solid N2 To 10 Gpa, Richard Alan Lesar
Richard Alan Lesar
Recently, LeSar and Gordon [J. Chem. Phys. 7 8, 4991 (1983)] reported calculations of the crystal structures of solid N2 and CO2 to 10 GPa using electron‐gas short‐range energies and pairwise dispersion energies that included only the anisotropicC 6/r 6 term. While the calculated zero temperature pressure‐volume curve was in excellent agreement with the experimental results, the structure that was calculated to be most stable at high pressure (the β‐O2structure with space group R3̄m) is not consistent with experimental spectroscopic results. Here we report calculations on solid N2 using a pairwise damped‐dispersion energy that includes terms up to C 1 …