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An approach based on orthogonal locality preserving projection (OLPP) and support vector data description (SVDD) is proposed for the performance degradation assessment of rolling bearings. Firstly, the extracted features are selected according to the correlation with root mean square of vibration signals. Secondly, dimension reduction is performed on the selected features with OLPP and principal components are obtained. In the following, the performance degradation indicator (PDI) is constructed with the principal components fused by SVDD. Finally, the proposed approach is verified with the lifecycle data of two rolling bearings. The results show that the PDI has good monotonicity and is sensitive to the initial fault. Besides, the noise in the PDI could be efficiently suppressed.

In this paper, an adaptive patch-based filter for Synthetic aperture Radar (SAR) Interferometric phase in the Fourier transform complex domain is proposed. The proposed filter fully utilizes the properties of locally planar terrain phase noise model so that the noise can be suppressed according to the local level of noise. Moreover, the denoising performance of the proposed filter is further improved by an adaptive selection strategy for patch size. The experimental results show that the proposed method delivers state-of-the-art denoising performance in terms of objective criteria.

In this letter, an approach based on spectral diversity and conventional Interferometric Synthetic Aperture Radar (InSAR) for Digital Elevation Model (DEM) reconstruction is proposed. Conventional InSAR technique often fails to correctly reconstruct the DEM due to the presence of discontinuities and/or interferometric noise. With the assistance of the spectral diversity method, the ill-posed phase-unwrapping can be regularized. Thus the capabilities of the conventional InSAR technique for DEM reconstruction can be notably improved. Comparing to the multi-channel InSAR technique, the proposed method requires less SAR images. Comparing to the multifrequency technique, the performance of the proposed method depends on the perpendicular or effective baseline and the ratio of the radar's carry frequency to the bandwidth between the central frequencies of the two sub-looks; while the multifrequency technique depends more on the range bandwidth. Thus, the proposed method is more flexible than the multifrequency technique. The effectiveness of the proposed algorithm is validated by experimental results using real data.

As to these bearings, whose outside diameter is large (d≥120), price is high, and life is long, the number of samples chosen is small in order to save sample quantity and test cost, not according to the standard. There are a lot of users to choose the bearings less than 8 pcs to test the life for comparing the different bearings quality. According to the trait of rolling bearing submitting to Weibull distribution and test data, this paper adopts no information prior distribution based on Bayes method, and presents point estimation of shape parameter and reliability, interval estimation of shape parameter, reliability, reliability life and mean life. This paper provides an available method for quantitative assessment of bearing reliability in terms of small sampling.