1,907 research outputs found

    Electronic scene generator expansion system

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    The design, fabrication, and installation of additions and modifications to the electronic scene generator located at the NASA Manned Spacecraft Center, Houston, Texas, are described. The equipment delivered was incorporated into the electronic scene generator to enhance its capabilities by providing: (1) additional source computer interfaces; (2) additional edges thereby allowing more detailed scenes; (3) the ability to share edges to effect economies in complex scenes; (4) the ability to use edges without the constraints of a configuration catalog; and (5) the simplified implementation of new environments and environment modifications

    Heavy Quarkonia from Classical SU(3) Yang-Mills Configurations

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    A generalized Cho-Faddeev-Niemi ansatz for SU(3) Yang-Mills is investigated. The corresponding classical field equations are solved for its simplest parametrization. From these solutions it is possible to define a confining central non-relativistic potential used to study heavy quarkonia. The associated spectra reproduces the experimental spectra with an error of less than 3% for charmonium and 1% for bottomonium. Moreover, the recently discovered new charmonium states can be accomodate in the spectra, keeping the same level of precision. The leptonic width show good agreement with the recent measurements. The charmonium and bottomonium E1 electromagnetic transitions widths are computed and compared with the experimental values.Comment: 3 pages. Talk at QNP06, 5th-10th June, Madrid, Spai

    A Swarm intelligence approach for biometrics verification and identification

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    In this paper we investigate a swarm intelligence classification approach for both biometrics verification and identification problems. We model the problem by representing biometric templates as ants, grouped in colonies representing the clients of a biometrics authentication system. The biometric template classification process is modeled as the aggregation of ants to colonies. When test input data is captured -- a new ant in our representation -- it will be influenced by the deposited phermonones related to the population of the colonies. We experiment with the Aggregation Pheromone density based Classifier (APC), and our results show that APC outperforms ``traditional'' techniques -- like 1-nearest-neighbour and Support Vector Machines -- and we also show that performance of APC are comparable to several state of the art face verification algorithms. The results here presented let us conclude that swarm intelligence approaches represent a very promising direction for further investigations for biometrics verification and identification

    Correlated Photon-Pair Emission from a Charged Single Quantum Dot

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    The optical creation and recombination of charged biexciton and trion complexes in an (In,Ga)As/GaAs quantum dot is investigated by micro-photoluminescence spectroscopy. Photon cross-correlation measurements demonstrate the temporally correlated decay of charged biexciton and trion states. Our calculations provide strong evidence for radiative decay from the excited trion state which allows for a deeper insight into the spin configurations and their dynamics in these systems.Comment: 5 pages, 3 figures, submitted for publicatio
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