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• Erosion rates decreased significantly, minimizing in 2018. • Severe and very high types of erosion treatment were highly effective. • Severe erosion with large slopes should be the next focus of treatment. • Topography and climate are the most influential factors in soil erosion. • A generalizable methodology for soil erosion research and watershed management. Decreasing soil erosion is essential for maintaining agricultural productivity, conserving water resources, sustaining ecosystem health, mitigating climate change, and ensuring sustainable regional development. We investigated the Loess Plateau, where soil erosion is typical and severe, to characterize the evolution of soil erosion and its driving mechanisms. Specifically, we calculated the effects of rainfall erosivity, soil erodibility, slope length and gradient, vegetation cover and management, and soil and water conservation measures, and then calculated the soil erosion modulus from 1990 to 2020 using the RUSLE model. Next, we applied the landscape pattern index to analyze soil erosion and explored its evolutionary characteristics of soil erosion. We also analyzed the importance differences in the influencing factors on the Loess Plateau using a random forest model and explored the spatial and temporal heterogeneity of the influencing factors at the county scale utilizing geographically and temporally weighted regression models. The results showed that (1) from 1990 to 2020, soil erosion in the study area, generally, initially increased and then decreased, and the soil erosion modulus decreased to its minimum in 2018, (27.37 t·hm−2·a-1). The severe erosion type was effectively managed, and the occupied area was reduced by 33,742 km2. (2) The distributions of two types of soil erosion, slight and severe, were more aggregated, and the complexity of the patches of very high and severe erosion was significantly reduced. (3) Climate, slope, and human activities are important factors affecting soil erosion, among which the slope has the greatest influence on the region. (4) Severe erosion areas with a more significant slope and drier climate should be the focus of future erosion control. Our study can provide a reference for soil erosion management on the Loess Plateau as well as globally. [ABSTRACT FROM AUTHOR]

Accelerating the upgrading of traditional energy industries has become a key area of concern for global green and sustainable development. Notably, few existing studies have focused on the spatial-temporal variability of energy industry advancedization and its resource-environment decoupling effect. This paper was the first to measure China's energy industry advancedization index based on the perspective of industry chain elements and value chain structure, analyzed the spatial-temporal evolution and elemental characteristics, and explored the resource-environment decoupling effect and nonlinear impact. The results showed that energy industry advancedization in China displayed a slow-growth trend from 2008 to 2020, and the spatial unevenness of energy industry capital and workforce advancedization gradually deepened. The decoupling effect of resource endowment dependence in the evolution of energy industry advancedization was better than that of environmental pollution, the spatial decoupling process was better in the eastern and central regions than in the western and northeastern regions, and the decoupling pressure of resources and environment in some regions was still significant. The trend of the nonlinear effect of energy industry advancedization on resource endowment dependence and environmental pollution showed an inverted "N" and "N" shape, respectively, and the nonlinear effect had obvious stage characteristics and regional heterogeneity. • An advancedization index is measured based on the energy industry value chain. • Low levels of energy industry advancedization are mostly energy-enriched areas. • The regional unevenness of the energy industry elements advancedization is deepening. • The pressure of resource-environment decoupling in the energy industry still exists. • Energy industry upgrading effects on resource-environment are nonlinear. [ABSTRACT FROM AUTHOR]

• Three types of learning styles—stable, adaptive and changeful are discovered in a reinforced driving task. • The evolutionary index is introduced to distinguish learning styles and depict the learning curve. • The β band EEG signal at parietal region is significantly activated in the whole learning process. Overtaking maneuvers occur when vehicle drivers pursue higher driving speeds or comfort scenarios through back-to-back lane-changing behaviors, which require active participation of mental resources and certain self-learning practices. However, few studies have investigated how brain activities change during overtaking. Moreover, the learning process, which indicates the heterogeneity of drivers from a process-based perspective, has been neglected. In this work, we studied varied overtaking and learning styles using electroencephalogram (EEG) signals collected from drivers during a simulated driving task with a possible learning process. The average speed, standard deviation of speed, steering wheel angle and lateral movement distance of overtaking behaviors are analyzed in these reinforced tasks to evaluate overtaking performance. Four types of overtaking styles (i.e., low-speed type, low-speed & strong-oscillation type, high-speed & strong-steering type, and high-speed & close-distance type) and three types of learning styles (i.e., stable, adaptive and changeful) are discovered, not only from eventual overtaking behaviors but also from behavioral changes in a certain learning process. EEG features, such as the power spectral density (PSD) in the θ, α, β and γ bands, are extracted to characterize driver mental states and to correlate with heterogeneous learning styles. The obtained results show that fatigue and fatigue confrontation are more likely with a stable learning style, and the mental workload is reduced with an adaptive learning style, whereas no significant changes in brain activity are apparent with a changeful learning style. Understanding and recognizing heterogeneous overtaking and learning styles with varying EEG patterns will be extremely useful in the future for deep integration of advanced driving assistance systems (ADASs) and brain computer interface (BCI) systems. [ABSTRACT FROM AUTHOR]

As urbanization increases, the city continues to interfere with an already-fragile oasis eco-environment in arid areas. This paper proposes a synthesised evaluation index system regarding the urbanization level from the perspectives of demographic, economic, spatial, and social urbanization. The eco-environment was characterised in terms of its level, endowment, pressure and response. Moreover, a coupling coordination degree model was established with respect to the coordination degree of urbanization and the eco-environment based on panel data of three county-level cities and 14 counties in the Kashgar metropolitan area from 1999 to 2016. The findings show the following: (i) Economic urbanization and the eco-environmental response contributed the most to the urbanization and eco-environmental systems of the Kashgar metropolitan area. (ii) The coordination effects of the urbanization and eco-environmental system in most counties and cities of the Kashgar metropolitan area were classified as the balanced development II 2 subcategory of intermediate uncoordinated development. This overall spatial pattern shows that county-level cities had significantly higher levels of urbanization and eco-environments than did counties. (iii) The double exponential curve between urbanization and the eco-environment was an inverted U-shaped curve. Urbanization had a stress effect on the eco-environment, whereas the eco-environment had a binding effect on urbanization. This study provides a reference for researching the evolutionary relationship between urbanization and the eco-environment in arid areas and provides decisional support for the more harmonious development of humans and nature in the Kashgar metropolitan area. [ABSTRACT FROM AUTHOR]

As novel cross sections, aerodynamic behaviors and vortex-induced vibration (VIV) inducement of split box girders, especially split three-box girders, are not fully understood. Analysis of vortex-excited force (VEF) evolutionary characteristics in the VIV process may reveal valuable information. Based on displacement and pressure measurement wind tunnel tests on a large-scale section model, the evolutionary characteristics of typical VEF indexes were expounded. VIV was divided into four stages: pre-VIV, ascent, extreme point, and descent. At the extreme point, high-order harmonics were found, which indicates that VEF has obvious nonlinearities. Mean and RMS values of global VEF appear to be controlled by upstream and downstream boxes. An increase in RMS values is the main cause of VIV. VEF spanwise correlation is mainly dominated by structural vibration at the extreme point, while spanwise distance is dominant in other stages. Local aerodynamic forces on the surfaces include upstream box surface (excluding partial lower surfaces of the wind fairing), upstream and downstream curved surfaces in upstream gap, upper surface of downstream box, and the wake are the main contributors to global VEF and the main cause of VIV. This work provides a comprehensive understanding of aerodynamic behaviors and VIV inducement of split three-box girder bridges. • Aerodynamic behavior of split three-box girder bridges were expounded. • Vortex-excited force show obvious nonlinearity. • An increase in RMS values is the main cause of vortex-induced vibration. • The gaps and the wake are the main causes of vortex-induced vibration. • Vibration rather than distance dominates at the maximum of vortex-induced vibration. [ABSTRACT FROM AUTHOR]

As an important research tool in the field of economic physics, complex networks have been widely used in various fields. In recent years, research on heterogeneous networks has become a new hotspot. For mergers and acquisitions, each deal consists of two aspects, namely, concerned parties and the deal event. There are heterogeneous features among the subjects, which could form a heterogeneous network, so the potential reasons for the existence of mergers and acquisitions involving multiple parties still need to be explored. With the continuous development of China's market economy and the continuous increase in the number of listed companies, mergers and acquisitions have become an important means for listed companies to optimize their allocation of resources and improve their industrial structures. The increasing size and quantity of mergers and acquisitions have made the relations among concerned parties closer. Therefore, a complex network relationship tends to form between merger and acquisition deals. To this end, this paper collected 2006–2015 merger and acquisition research data from Chinese listed companies and built a single mode derivative M&A network where two parties are involved in the same M&A event. Then, the evolutionary trend, community relations and M&A preference of the parties involved were explored by quantitative and qualitative analyses. The main research results include the following. (1) Mergers and acquisitions revealed a trend of dramatic increase, with a sharp increase in 2015. (2) Communities were apparently separated in the M&A network, with few contacts between each other. Most of the deals of the parties involved in mergers and acquisitions of the listed companies were sporadic, and there were frequent mergers and acquisitions between a small number of M&A subjects. But now the M&A market has changed and the so-called "two-eight" principle has been gradually broken down. More companies will also have frequent M&A transactions. (3) Parties involved in mergers and acquisitions were characterized by assortativity, which still exists although it has gradually weakened in the last five years, indicating that the parties involved in mergers mostly choose the target company of the merger according to their needs. The research results of this paper provide a method for further research on the M&A derivative network of the listed companies and the expansion of complex network applications as well as new ideas for the study of M&A networks. • Using complex network to build two parties are involved in the same M&A event network. • Communities of M&A were apparently separated with few contacts between each other. • There were frequent M&A between a small number subjects. • M&A participant assortativity has gradually weakened in the last five years. [ABSTRACT FROM AUTHOR]