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    Lens distortion correction by analysing the shape of patterns in Hough transform space : a thesis presented in partial fulfilment of the requirements for the degree of Master of Engineering in Electronics and Computer Engineering at Massey University, Manawatu, New Zealand

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    Many low cost, wide angle lenses suffer from lens distortion, resulting from a radial variation in the lens magnification. As a result, straight lines, particularly those in the periphery, appear curved. The Hough transform is a commonly used linear feature detection technique within an image. In Hough transform space, straight lines and curved lines have different shapes of peaks. This thesis proposes a lens distortion correction method named SLDC based on analysing the shape of patterns in the Hough transform space. It works by reconstructing the distorted line from significant points on the smile-shaped Hough pattern. It then optimises the distortion parameter by mapping the reconstructed curved line into a straight line and minimising the RMSE. From both simulation and correcting real world images, the SLDC provides encouraging results

    Hadronic decays of charmonia from BESII

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    Recent results on charmonia decays at BESII/BEPC are reported, including the observation of psi'-->K_S K_L, psi'--> Vector + Tensor and psi'--> Vector + Pseudoscalar for the measurement of the relative phase between the strong and electromagnetic decays of psi' and a test of the pQCD ``12% rule'' between psi' and J/psi decays; the test of the color-octet mechanism via chi_cJ --> p \bar{p} and chi_cJ-->\Lambda \bar{\Lambda}; the first observation of chi_c0--> f_0(980)f_0(980); and a study of the psi' and chi_cJ decays with K_S K_S in the final states.Comment: Invited talk in MESON 200

    Hadron Spectroscopy from BES and CLEOc

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    Recent results from BES and CLEOc experiments on hadron spectroscopy and charmonium decays using J/psi, psi' and psi'' data samples collected in e+e- annihilation are reviewed, including the observation of X(1835) in J/psi --> gamma pi+ pi- eta', study of the scalar particles in J/psi radiative and hadronic decays, as well as in chi_c0 hadronic decays, and the study of the ``\rho\pi puzzle'' in J/psi, psi', and psi'' decays. We also make a few comments on partial wave analysis, and the study of the \rho \pi puzzle.Comment: Invite talk at Hadron'05, Rio de Janero, Aug. 200
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