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George Maroulis

We report a study of the performance of density functional theory (DFT) methods in the prediction of electric properties for the ozone molecule. We have used a large, flexible basis set for the calculation of the dipole moment and the dipole (hyper)polarizability with the B1LYP, B3LYP, B3P86, B3PW91, G96PW91 and MPW91PW91 methods. The results are compared to high-level, conventional ab initiomethods. We rely on a rigorous approach in order to evaluate the proximity and similarity of theoretical descriptions obtained via DFT and conventional ab initiomethods. We find that compared to the most accurate ab initio, DFT methods predict reliable dipole polarizabilities and second dipole hyperpolarizabilities for ozone. Agreement is less good for the dipole moment and the first dipole hyperpolarizability. Overall, the performance of the DFT is similar to that of the accurate ab initiomethods.

Bruce A. Wade, Krishnendu Ghosh and Peter J. Tonellato

MetaGene is a software environment for gene analysis developed at the Bioinformatics Research Center, Medical College of Wisconsin. In this work, a new neural network optimization module is developed to enhance the prediction of gene features developed by MetaGene. The input of the neural network consists of gene feature predictions from several gene analysis engines used by MetaGene. When compared, these predictions are often in conflict. The output from the neural net is a synthesis of these individual predictions taking into account the degree of conflict detected. This optimized prediction provides a more accurate answer when compared to the default prediction of MetaGene or any single prediction engine’s solution.

CBSP: A Predictor of Sequences of Correlated Branches

A Way to Reduce Aliasing in Branch Prediction Tables

T. Haquin, C. Rochange and P. Sainrat

All current processors are using branch prediction in order to better exploit the pipeline. Branch prediction is based on limited size tables and thus several branches are sharing the same entry which is made of a simple 2-bit counter. This is called aliasing. Aliased branch predictors are subject to destructive interferences and removing them by the addition of a tag identifying precisely a branch to a 2-bit counter is prohibitive. An entry of our prediction table is made of several counters which predict a sequence of consecutive correlated branches and not only one. Thus, a tag can be added to an entry at a lower cost since the tag is shared by several branches. Each time a sequence is retrieved in the prediction table, it provides several predictions. An annex tagless predictor is solicited when a sequence is not found in the sequence table. Collisions are avoided in the sequence table but, to achieve a misprediction rate as low as the one of the current uptodate predictors, several tables should be used, each table being indexed through a different branch history length. Among the predictions provided by the sequences, a priority mechanism selects the most accurate i.e. the one provided by the table with the longest history. Finally, having tagged entries allows us to implement an intelligent system that dynamically adapts the branch history lengths according to the applications.

Patrizia Calaminici, Roberto Flores–Moreno and Andreas M. Köster

Density functional calculations of neutral and anionic tantalum trimer monoxide are presented. The calculations were performed employing scalar quasi–relativistic effective core potentials. Different isomers of Ta3O and Ta3O- were studied in order to determinethe ground state structures. For both systems a planar C2vstructure with an edge-boundoxygen atom was found as ground state. Equilibrium structure parameters, harmonic frequencies, adiabatic electron affinity and Kohn-Sham orbital diagrams are reported. The calculated values are in good agreement with the available experimental data obtained from negative ion photoelectron spectroscopy. The correlation diagram between the neutral and anionic Ta3O shows that, in agreement with the experimental prediction, the extra electron in the anionic system occupies a nonbonding orbital.

Wen, Bradean, Russell, Pourmohammadi, Harris and Ingham

applications to the prediction of internal  ows: A review. Computers & Fluids 15 , 151– 184. Nield, D. A. and Bejan, A. (1999). Convection in Porous Media , 2nd edn. Springer-Verlag, New York. Patankar, S. V. (1980). Numerical Heat Transfer and Fluid Flow . Hemisphere, Washington DC. Patankar, S. V. and