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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, …
Characterization Of The Transport Of Oxaloacetate By Pea Leaf Mitochondria, David J. Oliver, Griffin H. Walker
Characterization Of The Transport Of Oxaloacetate By Pea Leaf Mitochondria, David J. Oliver, Griffin H. Walker
David J. Oliver
Mitochondria isolated from pea (Pisum sativum L.) leaves are able to transport the keto acid, oxaloacetate, from the reaction medium into he mitochondrial matrix at high rates. The rate of uptake by the mitochondria was measured as the rate of disappearance of oxaloacetate from the reaction medium as it was reduced by matrix malate dehydrogenase using NADH provided by glycine oxidation. The oxaloacetate transporter was identifed as being distinct from the dicarboxylate and the α-ketoglutarate transporters because of its inhibitor sensitivities and its inability to interact with other potential substrates. Phthalonate and phthalate were competitive inhibitors of oxaloacetate transport with …
Theoretical Study Of Silylene Insertion Into N-H, O-H, F-H, P-H, S-H, And Cl-H Bonds, Krishnan Raghavachari, Jayaraman Chandrasekhar, Mark S. Gordon, Ken Dykema
Theoretical Study Of Silylene Insertion Into N-H, O-H, F-H, P-H, S-H, And Cl-H Bonds, Krishnan Raghavachari, Jayaraman Chandrasekhar, Mark S. Gordon, Ken Dykema
Mark S. Gordon
The potential energy surfaces for the insertion reactions of silylene into NH3, Hp, HF, PH3, H2S, and HCl have been characterized in detail by using ab initio molecular orbital theory, including electron correlation and zero-point corrections. All the interactions involve the initial formation of a donor-acceptor complex followed by a proton shift via an unsymmetrical high-energy transition state. The binding energies of the complexes as well as the rearrangement barriers for the hydrogen migration of these complexes to give the normal valent compounds have been calculated in all cases. The complex between SiH2 and NH3 exists in a deep minimum …
Ab Initio Study Of The Insertions Of Methylene And Silylene Into Methane, Silane, And Hydrogen, Mark S. Gordon, David R. Gano
Ab Initio Study Of The Insertions Of Methylene And Silylene Into Methane, Silane, And Hydrogen, Mark S. Gordon, David R. Gano
Mark S. Gordon
The transition states for several insertion reactions have been determined at the 3-21G level of theory. While the insertions of CH2 and SiH2 into the CH and SiH bonds of methane and silane, respectively, all have nonzero SCF barriers, only the insertion of silylene into methane retains a nonzero barrier when third-order Moller-Plesset perturbation theory corrections are included with the 6-31G* basis set. The intrinsic reaction coordinates for the carbene and silylene insertions into methane are used to provide a pictorial view of these reactions and to relate the calculations to earlier studies. The insertion of silylene into H2 is …
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 …
Process For The Preparation Of Protein Isolates Of Improved Quality From Vegetable Protein Sources, Lawrence A. Johnson, Hwei-Mei Wen
Process For The Preparation Of Protein Isolates Of Improved Quality From Vegetable Protein Sources, Lawrence A. Johnson, Hwei-Mei Wen
Lawrence A. Johnson
Protein isolates are recovered from vegetable protein sources, such as sunflower meal, by extracting the meal with an alkali solution in the presence of an alkali metal borohydride, and then acid precipitating the resulting aqueous protein extract phase to produce a protein isolate. Typically, the alkali metal borohydride is employed in an amount of at least about 20 ppm, based on the combined weight of vegetable meal and alkali solution. Protein isolates produced by this process exhibit improved color, palatability and/or nutritional value, and comprise highly desirable additives for food products, animal foods, etc.
Ab Initio Studies Of Hxypo And Xypoh Molecules, Mark S. Gordon, Jerry A. Boatz, Michael W. Schmidt
Ab Initio Studies Of Hxypo And Xypoh Molecules, Mark S. Gordon, Jerry A. Boatz, Michael W. Schmidt
Mark S. Gordon
Molecular orbital calculations have been carried out on a sequence of HXYPOH molecules, with X and Y = H, CH3, NH2, OH, OCH3, and F. The molecular structures are predicted with the ST0-2G* basis set. For the prediction of energies of isomerization to XYPOH species, single-point 3-21G* and 6-31G* calculations were used. The molecular dissociation energies of HXYPO to HPO + XY and to XPO + HY were calculated by augmenting the latter two basis sets with MP2 and MP3 perturbation corrections.
Hydrogen Abstractions By Triplet Methylene And Silylene, Mark S. Gordon
Hydrogen Abstractions By Triplet Methylene And Silylene, Mark S. Gordon
Mark S. Gordon
While the most common reactions of singlet methylenes are insertions into Y -H or multiple bonds, 1-3 triplet methylenes tend to abstract hydrogens from Y -H bonds. 1·2 Singlet silylenes are also known to insert,4-6 while little is known about the corresponding triplets. Several theoretical papers have been devoted to analyses of the insertions of singlet CH/-12 and SiHP-15 into a variety of bonds and the abstractions of hydrogen from H216-20 and CH417 by triplet methylene. Ab initio calculations including correlation predict that carbenes insert into Y-H9•11 ·12·15 bonds with no barrier, in agreement with the prevailing experimental evidence;1·2 however, …
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.
Theoretical Studies Of Cyclic C2si2h4 Molecules, Thomas A. Holme, Mark S. Gordon, Satoshi Yabushita, Michael W. Schmidt
Theoretical Studies Of Cyclic C2si2h4 Molecules, Thomas A. Holme, Mark S. Gordon, Satoshi Yabushita, Michael W. Schmidt
Mark S. Gordon
Thirteen cyclic C2Si2H4 isomers, including disilatetrahedrane and the disilacyclobutadienes, have been studied by using ab initio quantum mechanics. At the MP3/6-31G* / /3-21G level of computation, the silyl-substituted silacyclopropenylidene is found to be the most stable. Disilatetrahedrane is quite high on the energy surface, and the two possible planar 1,2-disilacyclobutadienes do not represent minima on this surface. Planar 1,3-disilacyclobutadiene is a stable structure and exhibits significant diradical character.
Theoretical Studies Of Polyvinyl-Substituted Carbenium And Silylenium Ions, Thanh Truong, Mark S. Gordon, Philip Boudjouk
Theoretical Studies Of Polyvinyl-Substituted Carbenium And Silylenium Ions, Thanh Truong, Mark S. Gordon, Philip Boudjouk
Mark S. Gordon
Ab initio (ST0-2G and 3-21G) calculations have been performed to analyze the ability of one, two, and three vinyl groups to stabilize the CH3 + and SiH3 + ions. Vinyl groups appear to be quite effective at stabilizing the positive charge on the silylenium ion, and successive vinylization preferentially stabilizes the silicon relative to the carbon ion.
Theoretical Study Of Methylsilanone And Five Of Its Isomers, Mark S. Gordon, Clayton George
Theoretical Study Of Methylsilanone And Five Of Its Isomers, Mark S. Gordon, Clayton George
Mark S. Gordon
By use of 3-21G SCF geometries and relative energies from MP3/6-31G* wave functions, methylsilanone has been found to be the most stable of the six isomers investigated. The relative stabilities of methylsilanone and silylformaldehyde are rationalized by the metathesis reaction H 2Si0 + C2H4 .... H 2CO + H 2CSiH4. This reaction is used to suggest that the C=O bond is about 10 kcaljmol stronger than Si=O.
Structure, Bonding, And Internal Rotation In Phosphine Oxide (H3po), Hydroxyphosphine (H2poh), And Hydroxyfluorophosphine (Hfpoh), Michael W. Schmidt, Satoshi Yabushita, Mark S. Gordon
Structure, Bonding, And Internal Rotation In Phosphine Oxide (H3po), Hydroxyphosphine (H2poh), And Hydroxyfluorophosphine (Hfpoh), Michael W. Schmidt, Satoshi Yabushita, Mark S. Gordon
Mark S. Gordon
The fundamental nature of the PO bond is reexamined by using ab initio (3-21G* and 6-31G*) wave functions and energy-localized orbitals. The bond is best described as a dative single bond augmented by 71' back-donation from the oxygen lone pairs. The isomerization pathway from H3PO to H2POH is followed by using the intrinsic reaction coordinate and localized orbitals. The latter, more stable, isomer has two forms, cis and trans, which are nearly equal in energy. The internal rotation barriers in this molecule and in HFPOH are examined with a Fourier analysis and compared with their nitrogen analogues. The major differences …
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 …