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AbstractThis study combined the Latent Dirichlet Allocation topic model to explore the potential topics of new energy vehicle (NEV) policies and their impacts on the corporate social responsibility (CSR) of new energy vehicle enterprises. The results reveal that financial subsidies, infrastructure development, and environmental protection are the most popular topics. And these three popular topics have significant positive impacts on the CSR of new energy vehicle enterprises, with infrastructure construction having the most significant impact. Additionally, the intensity of the positive impact on large‐scale enterprises is more significant compared with small‐scale enterprises, and the impact on state‐owned enterprises is more remarkable than on private enterprises. Moreover, these three popular topics have more significant impacts on CSR in China's eastern region. Finally, we conclude this study by discussing the theoretical and practical implications of these findings.

Abstract. Gravel cushions are widely used to absorb the impact energy of falling rocks
in open-pit mines. A particularly important application is to enhance the
energy-absorbing capacity of rockfall sheds. In this paper, we study how
varying the thickness and particle size of a gravel cushion influences its
energy-consumption and buffering effects. We performed a series of laboratory
drop tests by dropping blocks from a fixed height onto cushions of different
thicknesses and particle sizes. The results indicate that, for a given impact
energy, the cushion thickness has a strong influence on the measured
coefficient of restitution (COR) and therefore impact pressure. Additional
tests were performed to study how the radius of the block and the height it
is dropped from affect the measured COR. This showed that as the movement
height of the block is increased the COR also increases, and blocks with
larger radii exhibit a larger variability in measured COR. Finally, we
investigated the influence of rockfall block radius, r, movement height,
H, cushion thickness, h, and particle size, d, on the COR and the
damage depth, L, of the cushion. The test results reveal that the cushion
thickness is the primary design parameter, controlling not only COR, but also
the stability of the cushion material. The results provide a theoretical and
practical basis for the design of gravel cushions for rockfall protection.

Abstract. Slope failure, which causes destructive damage and
fatalities, is extremely common in mountainous areas. Therefore, the
stability and potential failure of slopes must be analysed accurately. For
most fractured rock slopes, the complexity and random distribution of
structural fractures make the aforementioned analyses considerably
challenging for engineers and geologists worldwide. This study aims to solve
this problem by proposing a comprehensive approach that combines the
discrete fracture network (DFN) modelling technique, the synthetic rock mass
(SRM) approach, and statistical analysis. Specifically, a real fractured
rock slope in Laohuding Quarry in Jixian County, China, is studied to show this
comprehensive approach. DFN simulation is performed to generate
non-persistent fractures in the cross section of the slope. Subsequently, the
SRM approach is applied to simulate the slope model using 2D particle flow
code software (PFC2D). A stability analysis is carried out based on the
improved gravity increase method, emphasizing the effect of stress
concentration throughout the formation of the critical slip surface. The
collapse, rotation, and fragmentation of blocks and the accumulation
distances are evaluated in the potential failure process of the rock slope.
A total of 100 slope models generated with different DFN models are used to repeat the
aforementioned analyses as a result of a high degree of variability in DFN
simulation. The critical slip surface, factor of safety, and accumulation
distance are selected by statistical analysis for safety assurance in slope
analysis and support.