Rocky desertification poverty (RDP) refers to rural poverty triggered or exacerbated by rocky desertification, which deprives farmers of opportunities for improving their financial conditions through agricultural production. As China implements strategies including building a moderately prosperous society, targeted poverty alleviation, and rural revitalization, issues concerning RDP have become the work foci for the Chinese government and research hotspots for Chinese academic circles. This paper provides a thorough review of the history, progress, challenges and prospects based on decades of RDP studies in Southwest China. First, we review the origin, definitions and historical development trends of RDP. Over nearly four decades, research on RDP can be framed as four stages: start-up, poverty alleviation and ecological reconstruction, rocky desertification comprehensive control and green development. We find that RDP research progress appears to be directly related to the Chinese government's policy support and decision-making in mitigating RDP. Second, previous findings are reviewed and summarised regarding four research aspects: relationship exploration between rocky desertification and rural poverty, mechanisms of rocky desertification for exacerbating poverty, strategies for eliminating RDP and anti-poverty benefit evaluations of rocky desertification control efforts. Third, the remaining challenges are identified and summarised, including the challenges of conducting theoretical research on RDP and consolidating achievements in eliminating RDP. We find that while many achievements have been made in the study of RDP in recent decades, the completeness and systematism of the theoretical system remain weak, and the guidance for empirical research is still insufficient. Finally, this research is fundamental in achieving rural revitalization in rocky desertification ar-

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Aiming at the problem of analyzing for the dynamic performances of the spindle bearings running at an extreme ultra-high-speed in high-speed electric spindles, a model is built by taking the inertia effects and EHL at the extreme ultra-high-speed into account. Based on the system simulation about a bearing on the movements of every ball, the contact areas states and the lubrication states between balls and both ring raceways, the thermal state inside the bearing and so on, the internal state performances such as the movements and the inertia forces of all the balls, the contact forces and the lubrication films and the temperatures in the contact areas between balls and both ring raceways are analyzed in some different working conditions and configurations. The simulation results showed that the main factors affecting the state performances of a bearing running at an extreme ultra-high-speed are the inertia effects of the balls and the overheating in the contact areas between the balls and both ring raceways, which indicates that it can be improved by adopting the ball material with smaller mass density and the structure with a smaller ball diameter and more ball elements.

A new arc-consistent viscous-spring artificial boundary (ACVAB) was proposed by changing a traditional flat artificial boundary based on the theory of viscous-spring artificial boundaries. Through examples, the concept underpinning the establishment and specific setting of the boundary in the finite element software were described. Through comparison with other commonly used artificial boundaries in an example for near-field wave analysis using the two-dimensional (2D) half-space model, the reliability of the ACVAB was verified. Furthermore, the ACVAB was used in the numerical analysis of the effects of an earthquake on underground structures. The results were compared with the shaking table test results on underground structures. On this basis, the applicability of the ACVAB to a numerical model of seismic response of underground structures was evaluated. The results show that the boundary is superior to common viscous-spring boundaries in terms of accuracy and stability, and therefore, it can be used to evaluate radiation damping effects of seismic response of underground structures and is easier to use.