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Expanded polystyrene (EPS) composite soil is composed of two solid constituents (cemented soil and EPS beads), which together with the inter-constituent interfaces form a unique mesoscopic structure. The macroscopic behavior of EPS composite soil has been widely investigated so far, but the focus has seldom been put on the meso-scale mechanisms behind the macroscopic deformation features and strength mobilization processes. In this study, systematic experiments and refined numerical simulations are utilized to examine the meso-scale mechanical responses of EPS composite soil under triaxial compression to reveal the associated mechanisms. Here, meso-scale is a scale smaller than a sample scale but larger than an EPS bead scale. First, the mechanical behavior of cemented soil, EPS material and their interface is obtained in experiments; their constitutive models are formulated, and the model parameters are calibrated based on experimental results. Then, experiments and refined numerical simulations of triaxial compression on EPS composite soil are performed. It is found that the rich macroscopic mechanical behavior of EPS composite soil has a mechanical source (contrast in mechanical behavior between EPS and cemented soil) and a geometric source (non-uniform distribution of EPS beads). The mechanical source leads to highly non-uniform stress and strain distributions within an EPS composite soil. The geometric source causes strain localization in zones with local concentration of EPS beads, leading to three macroscopic deformation modes, i.e., overall shear localization, local lateral expansion, and overall uniform expansion. In strength mobilization, cemented soil matrix first mobilizes its strength because it takes most of the load and contributes much to deformation at the early stage of triaxial compression. EPS beads are later progressively involved in the overall load bearing and deformation of the EPS composite soil sample. EPS beads make more contribution to stress than to strain due to its soft nature. • Constitutive descriptions of constituents of EPS composite soil are developed. • EPS composite soil behavior has both mechanical and geometric sources. • Cemented soil matrix first mobilizes its strength because it takes most of the load. • EPS beads are later progressively involved in load bearing and deformation. [ABSTRACT FROM AUTHOR]

Intelligent electric vehicles (EV) can transmit their location, driving status and other information to Intelligent Transportation Systems (ITS) through the Internet of vehicles (IoV) communication. Among them, the optimization of EV charging planning has great significance in finding a suitable charging station (CS) for users. However, the constraints of State-of-Charge (SOC) and driving direction are incomplete in current planning models. Meanwhile, the existing scheduling policy based on Deep Reinforcement Learning (DRL) suffers from slow convergence due to the fixed average change rate of the reward function. This paper establishes a comprehensive EV charging planning model (CCPM) and presents an efficient multi-vehicle scheduling algorithm (EMVSA). Firstly, CCPM calculates the travel time under the SOC constraints to ensure that CS is reachable and takes into account the direction constraint by minimizing the distance of the selected CS to the user's destination. Secondly, a novel reward shaping method, which gradually increases the average change rate of the reward function, is presented and proved theoretically to accelerate the convergence of EMVSA. On the real city road network data, experimental results show that CCPM can guarantee the reasonability of CS selection and direction, and that the convergence speed of EMVSA is significantly increased to get the optimal scheduling result. • An EV charging planning model considering state of charge and driving direction constraints is introduced. • A novel reward shaping method is presented to accelerate the convergence of the scheduling algorithm. • On the real city road network data, the model and the algorithm are verified by experiments. [ABSTRACT FROM AUTHOR]

Few satisfactory animal models of laryngopharyngeal reflux (LPR) is available. Interleukin-8 (IL-8) and vascular endothelial growth factor (VEGF) may be associated with the pathogenesis of LPR injuries and laryngeal carcinomas. To establish an animal model of LPR and to explore the related pathological changes and cytokine expression in the vocal cord tissue. Twenty rabbits were divided into experimental and control groups. Dilatation of the upper and lower esophageal sphincter were carried out in the experimental group. The pH of the pharynx, pathological, and ultrastructural changes of the laryngeal tissue, and expression of IL-8 and VEGF were compared between the experimental group and controls. pH monitoring results and the dilated intercellular space of the vocal cord mucosa showed that the experimental group developed laryngopharyngeal reflux. There were significant differences in the immunohistochemical staining scores of both IL-8 (P = 0.015) and VEGF (P = 0.007) between the experimental and control groups in the vocal cord tissue. We successfully established a model of LPR, showing histopathological and ultrastructural changes consistent with the disease. The expression of IL-8 and VEGF may increase during the pathogenesis of LPR. [ABSTRACT FROM AUTHOR]

Abstract Mineral resources are still the rigid demand of China's development and their sustainability assessment is central to regional development. This paper introduces an improved Analytic Hierarchy Process-based Normal cloud model which incorporated randomness and fuzziness and presents an index system applicable to empirical analysis on 31 provinces of China. The weight system of evaluation indicators is determined by an improved analytic hierarchy process (IAHP) approach with good accessibility and attainability. Regional disparities of resources sustainability are demonstrated by spatial distributions of mineral resources sustainability with the help of GIS technology. The sustainability level is determined by the combination of resources, environment and society dimensions. The results indicate that the areas with high sustainability do not necessarily happen in resource-rich regions. The most important implications are the relatively lower sustainability of the developed areas and the higher sustainability in western provinces. The scores for indicators reveal that compared with western and central areas, the coastal provinces are less sustainable in environmental carrying capacity, but with higher sustainable social supporting capacity. Robustness test notes that the results are sensitive to the adjustment of weight system due to the preference of decision makers. Finally, differentiated regional strategies for improving overall sustainability are proposed. Graphical abstract Image Highlights • Normal cloud model is applied to assess sustainability of mineral resources (SMR). • An assessment system of SMR is developed for Chinese province. • The weights are obtained by improved analytic hierarchy process and an expert survey. • Resource-rich areas have high levels of SMR but with some exceptions. • Regional SMR is sensitive to the preference of decision makers. [ABSTRACT FROM AUTHOR]

Abandoned coal mine reutilization plays a critical role in the sustainable development of the mining industry. Scientific decisions on reuse modes are a prerequisite and crucial issue to efficiently explore the idle resources of abandoned mines. This paper classified the reuse modes into 6 types with 19 sub-patterns and generalized the influence conditions into 3 categories with 17 sub-indexes, including mine conditions, natural and geological conditions, and supplementary conditions based on literature review and data sources. A logical deduction method named "condition-mode" was proposed from the constraint conditions and their degree of constraint to select the preliminary reutilization patterns of abandoned mines. Finally, a practical example of the Beijing west mining area was introduced to demonstrate the applicability and feasibility of the proposed method. The results indicate that this method can be employed to select some potential reuse patterns for abandoned underground coal mines. The most important implications are that the significance of more detailed analyses and techno-economic appraisals on multiple schemes from these decision results, which suggests a stepwise integration approach to generate a more promising subset of inference results. The research can provide a reference for the reuse of underground coal mines that have been closed or will be closed. • The reuse ways of abandoned coal mine are grouped into 6 modes with 19 sub-patterns. • The constraints of each pattern are analyzed and summarized into 3 categories. • Abandoned coal mines reutilization is an integration of solid, space, and wasteland. • A logical inference method from constraints to reuse modes is proposed. • The preliminarily screened reuse modes narrow the scope for further discussion. [ABSTRACT FROM AUTHOR]

Highlights • The failure effect of dynamic source is more sensitive to source location. • The dynamic disturbance is deeply influenced by source location. • Burst effect of dynamic source can also be reduced duo to rock intensity weakening. • The occurrence of rock burst also depends on static stress field around the coal face. Abstract Rock burst, a serious seismic hazard in underground coal mining, is usually induced by the coupling effect of static stress and mining-induced dynamic loading. This paper chosen an underground longwall face (LW10302) in Baodian Coal Mine as the numerical simulation model, selecting measured tremor wave which located about 150 m above the goafing of LW10301 as dynamic source, and the failure effect of dynamic loading on coal seam entry and its influential factors can be simulated systematically by FLAC3D. By changing source energy, source location, coal-rock property, the simulation results show that failure effect of dynamic source is more sensitive to source location, followed closely by source energy, and then the rock property. That is, dynamic disturbance is deeply influenced by source location, which is decreased in exponential attenuation with the increasing of transmission distance, while it also increases largely with the source energy increasing. Meanwhile, Burst effect of dynamic source can also be reduced duo to rock integrity reduction and intensity weakening, which the corresponding dynamic loading can be decreased to even less than 40%, but the influence degree may be reduced in the condition of shorter transmission distance. Moreover, the occurrence of rock burst also depends on static stress field around the coal face. Thus, the corresponding measures should be carried out simultaneously to reduce the disturbance effect of dynamic source and static stress concentration. The conclusions can provide theoretical reference to rock burst controlling in underground mining. [ABSTRACT FROM AUTHOR]