No abstract

Detailed surface topography is important when analyzing the stability of slopes. Recent advances in new technologies such as interferometric synthetic aperture radar and light detection and ranging have allowed us to obtain high-precision profiles of distant landscapes and objects including detailed slope information for three-dimensional (3D) slope stability analysis. However, techniques of reconstructing 3D numerical models from scanned data of slope geometry have not been well investigated or tested. This paper proposes a comprehensive approach that integrates laser scanning and finite element method for slope stability analysis, particularly failure prediction under precipitation scenarios. The methodology is applied to a slope in the Wenchuan earthquake-stricken mountainous region that failed in 2013, triggered by severe rainfall. The modelling results show that the surface sampling resolution can affect the prediction accuracy of the potential failure zones. When constructing the slope model, the selected surface grid should be fine enough to capture the important topographic features of the slope while minimizing computation demand. This paper confirms that the proposed method can be successfully used to identify the potential failure zones of the investigated slope under severe rainfall conditions.

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The circulation of silver between the Americas, Europe and China has provided a critical impetus for modern globalization since the 16th century. Even though substantial documentary information about this process has been collected and processed, there is still an ongoing debate about its underlying mechanism and the nature of the economic model. This article argues that the scientific analyses of the silver bullion and coins of Ming–Qing China and the Americas can offer a new source of information about this issue. This pilot study shows that the Ag concentration in Ming and Qing silver bullion is higher than that of the Americas, by around 3% and 8%, respectively. In particular, Qing silver bullion made in different reigns shows a remarkably consistent Ag content. Such a difference in the fineness could further contribute to the colossal arbitrage noted by scholars for decades, resulting in high volumes of global trading fundamentally driven by the higher price of silver in China. While quantifying its exact economic and political impacts still appears a distant prospect, as the current database is rather sketchy and many intermediate processes remain unclear, integrating scientific analyses into historical research illustrates several new patterns which helps to rethink the global silver circulation in the early modern period.