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Projecting the original data into a low-dimensional target space for feature extraction is a common method. Recently, presentation-based approaches have been widely concerned and many feature extraction algorithms based on this have been proposed. However, in the process of acquiring real data, the pollution of complex noise cannot always be avoided, which will greatly increase the difficulty of feature extraction and even lead to failed feature extraction results. Thus, a robust image feature extraction model based on Orthogonal Low-Rank Projection Learning (OLRPL) is proposed, in which the introduction of orthogonal matrix can encourage the preservation of the main components of the sample. Particularly, the row sparsity constraint introduced on the projection matrix can encourage the features to be more compact, discriminative and interpretable. In particular, the Weighted Truncated Schatten \emph{p}-norm (WTSN) is proposed to better solve the optimization problem of low-rank constraints. At the same time, the correntropy is applied in OLRPL to suppress the complex noise in the data and thus improve the robustness of the model. Finally, we specially design a robust classification loss function so that our model can be fitted the supervised scene effectively. Experiments on five general databases have proved that OLRPL has better effectiveness and robustness than existing advanced methods.

Cs2LiLaBr6:Ce (CLLB) scintillation detector has excellent energy resolution and high light output to gamma-rays, with excellent neutron/gamma-rays discrimination performance. Its applications are mainly limited to crystal growth with large size and high quality. In this paper, high performance CLLB was grown, encapsulated and tested. The vertical Bridgman method was employed to grow Cs2LiLaBr6:1%Ce crystals. By regulating the temperature, the maximum temperature gradient of the growth furnace was adjusted to the position of crystal precipitation. To avoid the non-uniform melting component area, the non-stoichiometric of raw materials increasing the excess of 100% LiBr were used. The crystals was developed successfully with 1 inch diameter, 5 cm length, and 4.32 g/mL density. Finally, the crystal was encapsulated and tested, with an energy resolution of 4.0% and relative (NaI) optical output of 1.14 to 0.662 MeV gamma-rays, and an absolute optical output of 47665 Photons/MeV to 0.511 MeV gamma-rays; The figure of merit (FOM) of the neutron/gamma-rays discrimination is 1.27 enabled by charge comparison method. The scintillation decay time of the two kinds of signals is measured respectively by the optical flux simulation method, with a fast component of about 0.19 μs and a slow component of 1.08 μs. Results show that the neutron signals has a higher fast component proportion to gamma-rays signals.