Understanding granular flows past an obstacle is very important to most possibly avoid damage to human properties and infrastructures. The present paper investigates the influence of an obstacle on dry and fluid-saturated granular flows to gain insights into physics behind them. To this end, we extend the existing depth-integrated theory by considering additional effects from the pore fluid pressure and the granular dilatancy. We revisit a largescale experiment to validate the extended theory. The good agreement between numerical results and experimental data reveals that the granular dilatancy plays a crucial role in the mobility and peak depth. Furthermore, we investigate the influence of obstacles on dynamics of dry granular flows by comparing numerical results with experimental data. It is shown that shock waves, dead zones and vacuum (grain-free zone) well observed in the experiments can be captured. Additionally, a fluid-saturated granular flow past the same obstacle is numerically simulated to interpret the role of the interstitial fluid, especially the pore fluid pressure, in the fluid-granular mixture causing distinct dynamic behaviours from those of a dry granular flow. It is also found that the granular dilatancy has a significant influence on the pore fluid pressure which can mitigate the granular friction. This is consistent with many experimental observations. Additionally, it is demonstrated that the pore fluid pressure is prone to elevate the flow depth in front of a cuboid dam (but not in front of a forward-facing tetrahedral wedge), which in turn mitigates the granular friction. The findings are helpful to understand complex behaviours encountered in geophysical flows and industrial processes.

Personification is widely acknowledged for its central role in the understanding of a nation. However, empirical evidence of its pervasiveness in authentic language data is lacking. In a self-built corpus of news report, this study coded, categorized, and analyzed the metaphoric and metonymic use of two country names: China and Australia. The distribution of the use of country names shows a continuum ranging from the literal, through metonymy, to metaphor. A clear majority of the figurative use of national names in the corpus lies in the category of metonymy, and the fuzzy area between metonymy and metaphor. In contrast, metaphors only take up a minor proportion, and most of them are based on metonymic link. By examining the mundane and seemingly literate use of country names, this study exemplifies that consistent patterns of conventional metonymy and metaphor are able to incur significant cognitive impact. Thus, this study calls for more attention on metonymy and metonymy-metaphor interaction in empirical studies on metaphor.

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