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• Considering the randomness of the equivalent conicity of the wheelset system. • The analysis of wheelset system under non-smooth condition is more appropriate. • Considering the time delay displacement feedback control in the primary suspension. • Stochastic D(P)-bifurcation occur in the probabilistic sense in the wheelset system. • The hunting stability of the wheelset system during operation were analyzed. Considering not only the stochastic track irregularity and the possible effect of stochastic parameter excitation, but also the time delay of spring, that is, its response is in place, but the force generated is not in place, a stochastic delay wheelset system is established. The infinite dimensional system is reduced to the finite dimensional stochastic differential equation by using the center manifold, and further reduced to a one-dimensional diffusion process by using the stochastic averaging method. The stability of the wheelset system is obtained by analyzing the singular boundary theory and calculating the maximum Lyapunov exponent. The conditions and types of stochastic bifurcation in wheelset system are obtained by combining probability density function. The numerical simulation verifies the correctness of the theoretical analysis and shows that the time delay affects the critical hunting instability speed of wheelset. The stochastic term affects the lateral displacement of the stochastic delay wheelset system. [ABSTRACT FROM AUTHOR]

Globalization has deeply changed the rural socio-economic form and spatial pattern, and caused a comprehensive and profound transformation of rural industries. By establishing a theoretical analysis framework for industrial transformation, this paper firstly reveals the internal mechanism of industrial transformation to promote the diversified development and comprehensive vitalization of rural areas. Taking Tengtou, a developed coastal village in southeast China, as the study area, we try to analyze its developing stages and the process of industrial transformation since 1965, and provide implications for China's rural vitalization towards globalization. Driven by external forces of globalization, rural development elements interact with each other for restructuring and combine with the internal development needs of rural areas to jointly promote the transformation of rural industries, with a major transformation path of "factor flow-structure adjustment-function expansion". The sound leadership of rural cadres and the growth of the collective economy are important catalysts for Tengtou's industrial transformation. The restructuring of village-owned enterprises has endowed Tengtou with the vitality for industries development, the ability to participate in global market competition, and the development resilience for overcoming obstacles. The great practice of industrial transformation in Tengtou has important enlightenment for China or even the developing world's rural vitalization: strengthening the building of village level party organization and the leadership of cadres; innovating the governance model of village level to develop the collective economy; promoting the integrated development of the industries to support the rural vitalization; and protecting the ecological environment to promote the rural harmonious development. Developing the global rural with Chinese characteristics is still in preliminary stage, the valuable Tengtou spirit of "plowing to the end, innovating never ends" deserves to be continuously carried forward to promote the rural industry development and comprehensive rural vitalization via innovation. • "Factor flow-structure adjustment-function expansion" is the major transformation path. • Sound rural leadership and growth of collective economy are catalysts for industrial transformation. • Restructuring of village-owned enterprises invigorates industrial transformation. • Transforming from labor-intensive to capital and technology intensive to obtain larger share of international market. [ABSTRACT FROM AUTHOR]

[Display omitted] • The environmental level of La induced a systemic endocytosis in S. alfredii. • La-induced systemic endocytosis increased Cd and PSNP accumulation in S. alfredii. • La improved plant tolerance to enhance the phytoextraction of Cd and PSNPs. • La-improved plant tolerance was related to the increased uptake of nutrients. Phytoextraction based on hyperaccumulators is a sustainable bioremediation technology. However, hyperaccumulators can only accumulate a single type of pollutants and need long remediation times, inhibiting simultaneous phytoextraction of co-occurring inorganic and organic pollutants. Here, the study indicated that the environmental level of lanthanum, as an emerging pollutant, was absorbed by leaves and induced endocytosis from leaves to roots (systemic endocytosis) in Sedum alfredii. Cadmium and polystyrene nanoplastics were simultaneously absorbed by root cells through systemic endocytosis, increasing the accumulation of these pollutants in Sedum alfredii. One possible mechanism of improving phytoextraction of co-occurring cadmium and polystyrene nanoplastics is that the lanthanum-induced system endocytosis increased the nutrient absorption of Sedum alfredii , thus increasing the activity of antioxidant enzymes, enhancing photosynthesis, biomass, and plant tolerance. These findings provide a new empirical basis and strategy for the simultaneous phytoremediation of co-occurring inorganic and organic pollutants in environments. [ABSTRACT FROM AUTHOR]

Wheelset bearing is one of the crucial rotating elements in the train bogie. Detection of wheelset bearing defect comes with many challenges due to complex wheel/rail excitation and the horrible working condition. The parametric dictionary sparse representation provides a practical path to detect the weak fault of wheelset bearing. However, the parametric dictionary obtained by the classical correlation filtering algorithm (CFA) is hard to match the analyzed signal's underlying fault impact characteristic. A novel parametric dictionary design algorithm named fault impact matching algorithm (FIMA) combining Orthogonal matching pursuit (OMP) is proposed to address the problem in this paper. The core of the FIMA mainly comprises two stages: partial segmentation and global analysis. Two indexes, correlation function (CF) and kurtosis, are used to comprehensively evaluate the partial and global matching degree between the Laplace wavelet and the signal. The proposed method's effectiveness is verified by the fault simulation analysis and the practical wheelset bearing fault signals (outer and inner race fault). Some comparison studies demonstrate that the proposed method outperforms the CFA–OMP, the K-SVD–OMP and some time–frequency decomposition methods, such as EWT and VMD, in detecting the bearing weak defects. [ABSTRACT FROM AUTHOR]