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To solve the challenge of visual tracking in complex environment, a multi-criteria confidence evaluation strategy is proposed in this paper. Three kinds of criteria are introduced to comprehensively evaluate and analyze the confidence of those tracking results obtained by adaptive spatially-regularized correlation filters (ASRCF). The evaluation result is further utilized to establish the sample management and template updating mechanism, which aims to obtain the best template in the tracking process. The obtained template is used to update both scale filters and position filters in ASRCF. Experimental results on OTB100 and TC128 verify that the proposed method is more robustness compared with other similar algorithms.

To improve the decreased recognition performance for truck license plate in complex mine environment, which is caused by such factors as polluted, damaged, a robust license plate recognition method is proposed. Firstly, several candidate locations of license plate in the truck image are obtained by utilizing features of both edge and color. Furthermore, the parameter of license plate area intersection ratio is defined to find the precise localization among those above candidates. Then, a character segmentation scheme based on the gray projection method and morphological operator is used to remove those interference factors, such as frame, rivet and stain and uneven illumination. Finally, to increase the robustness of characters recognition by CNN, a self-built license plate character dataset is constructed, which contains various polluted samples obtained by manual simulation. As shown by the experimental results, the proposed method has higher accuracy in license plate location, and obtains an improvement on character recognition accuracy by 4% compared to other existed methods.

The surface of a Cr2O3 (0001) film epitaxially grown on Cr undergoes an unusual reentrant sequence of structural phase transitions. In order to understand the underlying microscopic mechanisms, the structural and magnetic properties of the Cr2O3 (0001) surface are here studied using first-principles electronic structure calculations. Two competing surface Cr sites are identified. The energetics of the surface is described by a configurational Hamiltonian with parameters determined using total energy calculations for several surface supercells. Effects of epitaxial strain and magnetic ordering on configurational interaction are also included. The thermodynamics of the system is studied using Monte Carlo simulations. At zero strain the surface undergoes an ordering phase transition at 165 K. Tensile epitaxial strain together with antiferromagnetic ordering drive the system toward strong configurational frustration, suggesting the mechanism for the disordering phase transition at lower temperatures., Comment: 12 pages, 9 figures, to be published in Phys. Rev. B

The electronic structure and magnetism of chromia (corundum-type Cr2O3) are studied using full-potential first-principles calculations. The electronic correlations are included within the LSDA+U method. The energies of different magnetic configurations are very well fitted by the Heisenberg Hamiltonian with strong exchange interaction with two nearest neighbors and additional weak interaction up to the fifth neighbor shell. These energies are insensitive to the position of the oxygen states, indicating that magnetism in Cr2O3 is dominated by direct exchange. The Neel temperature is calculated using the pair-cluster approximation for localized quantum spins of magnitude 3/2. Very good agreement with experiment is found for all properties including the equilibrium volume, spectral density, local magnetic moment, band gap, and the Neel temperature for the values of U and J that are close to those obtained within the constrained occupation method. The band gap is of the Mott-Hubbard type., Comment: 6 pages, 2 eps figures

Iridium adsorption on gamma-Al2O3 (001) surface has been studied using the ab initio calculation method and the electronic structures of the bare and the Ir adsorbed gamma-Al2O3 (001) surfaces have been analyzed. By modeling different adsorption sites, one can conclude that the energetically most favorable sites for the Ir are the top sites of the O atoms at the gamma-Al2O3 (001) surface terminated with octahedral Al. Charge redistribution around the Ir atom adsorbed on the surface improves file activity of the Ir atom as a catalyst. (C) 2008 Elsevier B.V. All rights reserved.

The electrochemical thermodynamic and kinetic characteristics of rechargeable batteries are critically influenced by the ordering of mobile ions in electrodes or solid electrolytes. However, because of the experimental difficulty of capturing the lighter migration ion coupled with the theoretical limitation of searching for ordered phases in a constrained cell, predicting stable ordered phases involving cell transformations or at extremely dilute concentrations remains challenging. Here, a group-subgroup transformation method based on lattice transformation and Wyckoff-position splitting is employed to predict the ordered ground states. We reproduce the previously reported Li0.75CoO2, Li0.8333CoO2, and Li0.8571CoO2 phases and report a new Li0.875CoO2 ground state. Taking the advantage of Wyckoff-position splitting in reducing the number of configurations, we identify the stablest Li0.0625C6 dilute phase in Li-ion intercalated graphite. We also resolve the Li/La/vacancy ordering in Li3xLa2/3−xTiO3 (0 < x < 0.167), which explains the observed Li-ion diffusion anisotropy. These findings provide important insight towards understanding the rechargeable battery chemistry.