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A simplified 3D FE model based on McCormick's model is developed to numerically predict the spatiotemporal behaviors of the PLC effect in Ti-12Mo alloy tensile tests at 350 degrees C with strain rates from the order of $10^{-4}$ s$^{-1}$ to $10^{-2}$ s$^{-1}$. The material parameter identification procedure is firstly presented in details, and the simulated results are highly consistent with experimental ones, especially in terms of stress drop magnitudes and PLC band widths. The distribution of simulated stress drop magnitudes at a constant tensile velocity (0.01 mm/s) follows a normal distribution and its peak value is in the range of 26-28 MPa. Furthermore, the simulated band width slightly fluctuates with the increase of true strain and its average value is about 1.5 mm. Besides, the staircase behavior of strain-time curves and the hopping propagation of the PLC band are observed in Ti-12Mo alloy tensile process, which are related to the strain localization and stress drop magnitudes.

It is challenging to align multi-exposed images due to large illumination variations, especially in presence of saturated regions. In this paper, a novel image alignment algorithm is proposed to cope with the multi-exposed images with saturated regions. Specifically, the multi-exposed images are first normalized by using intensity mapping functions (IMFs) in consideration of saturated pixels. Then, the normalized images are coded by using the local binary pattern (LBP). Finally, the coded images are aligned by formulating an optimization problem by using a differentiable Hamming distance. Experimental results show that the proposed algorithm outperforms state-of-the-art alignment methods for multi-exposed images in terms of alignment accuracy and robustness to exposure values.