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The effective detection and tracking of low, small and slow targets is a current hot issue in the radar field. The paper is a sequel to radar weak target detection based on RFT and AMF fusion focus, and concentrates on the tracking of typical UAVs by pulse Doppler radar. The implementations of tracking algorithm mainly include: first, the preprocessing of the plots centroid processing and the multi-frame acceleration estimation has been applied. Then the labeled multi-Bernoulli (LMB) smoother is used for the multi-target tracking. Finally, the final trajectories of targets are output after trajectory continuity judgment and effective trajectory extraction. The LMB smoother can output the smoothed trajectories of targets, therefore, improving the estimation accuracy of distance and velocity. Trajectory continuity judgment and effective track extraction can effectively overcome the problems of breaking trajectory caused by velocity jitter and false trajectory caused by velocity ambiguity. The comprehensive score rate to process multiple test data is 96.67%, which verifies the effectiveness and robustness of the proposed tracking algorithm.

Large-size and high-quality single crystal diamond synthesized by microwave plasma chemical vapor deposition (MPCVD) have excellent physical and chemical properties, which makes them have great application prospects in jewelry, electronics, nuclear and ray detection and other industry fields. During CVD single crystal diamond growth, it is found that there is an obvious interface between the substrate and the epitaxial layer, as well as between the multiple growth layers which stop-continue to grow. The interface region was analyzed by polarization microscope, Raman spectra and photoluminescence spectra (PL). The bright image under polarization microscope and higher content of NV color centers compared with substrate and its epitaxial layers indicate that the interface area has high defect and impurity content. The results show that some measures should be taken to control the quality of high-quality single crystal diamond at the initial stage, and the preparation should be completed in one growth cycle as far as possible. [ABSTRACT FROM AUTHOR]

Based on the characteristics of the morphological filter and the TIN-based progressive filter, a high-quality LiDAR point cloud filtering algorithm combining Morphological grayscale reconstruction and TIN Models is proposed in this paper. Its main strategies are: 1 Implementing morphological grayscale reconstruction with a priority of Type I Error and non-minimum suppression. In this step, LiDAR point clouds are tagged as Reliable terrain points G, suspicious terrain points S and suspicious Non-terrain points NG; 2 Suspicious non-terrain points are further tagged based on the iterative order of Morphological grayscale reconstruction. In this step, small and constant height interval is used to filter the possible non-terrain points at different elevation; 3 Constructing the initial TIN from points G and further filtering points S and NG points, respectively, by adaptively adjusting the parameters of the ground point criterion at associated point layer. We did an experiment with 15 ISPRS test data sets and assessed the results with the standard criterion as found in the literature. The result shows that proposed filtering algorithm dramatically improved filtering quality, even for complex terrain. [ABSTRACT FROM AUTHOR]