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Objective As the development and utilization of urban underground space advances towards the three-dimensional and multi-dimensional direction, there are more and more over-crossing and under-crossing urban rail transit projects. Among them, the close under-crossing construction of new stations with large cross-section has a significant impact on the surrounding environment. Therefore, it is urgent to carry out an in-depth study on the ground settlement and deformation law of existing stations during the new station construction process closely under-crossing existing stations by Pile-Beam-Arch (PBA) method. Method Based on the actual engineering case of Beijing Metro Line 6 Pinguoyuan Station, which closely under-crosses the existing station with same name on Metro Line 1, the law of ground settlement and deformation of the existing station is analyzed by adopting numerical simulation method in the study. By comparing the actual monitoring data, the actual situation of ground settlement and deformation of the existing station during the construction process is further verified, and the numerical simulation results are compared and analyzed with the measured data. Result & Conclusion The most unfavorable stages for ground settlement and existing structure deformation are the guide hole excavation stage and the second lining arch stage of PBA method. After the completion of second lining arch construction, both the ground settlement and the deformation of the existing structure show rebound phenomenon. In addition, the stiffness of the existing station has a significant inhibiting effect on the ground settlement above, which is manifested in the fact that the ground settlement value of the overlapping section is smaller than that of the non-overlapping section. The deformation of the existing station structure caused by new station constructed with PBA method is mainly the rigid body displacement, while it caused track structure deformation is mainly the overturning deformation, which is locally manifested as rigid body displacement.

Objective A new station constructed with PBA method closely undercrossing existing station will influence the deformation of the latter′s structure. The influence law needs to be studied. Method Based on the project of Pingguoyuan Station on Beijing Metro Line 6 closely undercrossing the existing station, a finite element model is established by the GTS NX finite element analysis software, and its computing accuracy is verified through comparison with the actual monitored results. According to the calculation results of the finite element model, the impact of PBA (pile beam arch) method construction on the existing station is studied, and the influence of the existing station on land subsidence is analyzed. Result & Conclusion In the process of PBA construction, the construction stages that greatly affect the track structure and the building structure of the existing station are the guiding hole excavation and the second lining arch stages. The closer the construction is to the existing station, the smaller the land subsidence. When the monitoring sections are at the same location, the larger the existing station structure section, the smaller the land subsidence. With the same section size of the existing station, the closer to the excavation centerline of the new station, the greater the land subsidence value. The influence range of the existing station is related to the sectional size of the existing station structure.

As mineral resources become increasingly scarce, the search for potential ore deposits presents a significant challenge in geological exploration. Subjective factors often constrain traditional knowledge-driven approaches, while purely data-driven methods may overlook the geological significance of data relationships, potentially compromising the accuracy and reliability of predictions. To address these issues, this study proposes a novel mineral prediction model that integrates fuzzy comprehensive evaluation with both knowledge-driven and data-driven approaches (FCEKDD), resulting in an optimized comprehensive mineral prediction model based on multi-source geoscience data. This model establishes comprehensive exploration indicators based on expert knowledge and quantitatively assesses these indicators through fuzzy evaluation methods to evaluate mineralization potential, thereby delineating exploration targets within the study area. Ultimately, a three-layer predictive framework is constructed using the C-A fractal method. Experimental results indicate that 57.1% of known mineral points are within the primary prediction zone, thus demonstrating the model's high predictive accuracy. Comparisons with a random forest model reveal that the FCEKDD model has advantages in addressing geoscience data uncertainty and interpreting geological phenomena. This research validates the reliability and applicability of the proposed model in mineral exploration mapping, providing an effective solution for future mineral resource exploration. [ABSTRACT FROM AUTHOR]

Artificial ears with intelligence, which can sensitively detect sound—a variant of pressure—and generate consciousness and logical decision‐making abilities, hold great promise to transform life. However, despite the emerging flexible sensors for sound detection, most success is limited to very simple phonemes, such as a couple of letters or words, probably due to the lack of device sensitivity and capability. Herein, the construction of ultrasensitive artificial eardrums enabling intelligent song recognition is reported. This strategy employs novel geometric engineering of sensing units in the soft microstructure array (to significantly reduce effective modulus) along with complex song recognition exploration leveraging machine learning algorithms. Unprecedented pressure sensitivity (6.9 × 103 kPa−1) is demonstrated in a sensor with a hollow pyramid architecture with porous slants. The integrated device exhibits unparalleled (exceeding by 1–2 orders of magnitude compared with reported benchmark samples) sound detection sensitivity, and can accurately identify 100% (for training set) and 97.7% (for test set) of a database of the segments from 77 songs varying in language, style, and singer. Overall, the results highlight the outstanding performance of the hollow‐microstructure‐based sensor, indicating its potential applications in human–machine interaction and wearable acoustical technologies. [ABSTRACT FROM AUTHOR]

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The modeling of blind people's behavior is an important topic in pedestrian evacuation dynamics. In order to study movement characteristics of blind people in evacuation process and the effect of indoor obstacles on the evacuation efficiency of blind people, an extended cellular automata model is proposed to simulate blind people evacuation by considering the influence of obstacles. The control variable method is adopted to study the effect of indoor obstacles on the blind evacuation efficiency rule. The numerical simulation is applied to analyze the evacuation process of blind people under different setting (e.g. the location, size and other factors) of obstacles and different evacuation scenarios. The shunt effect of obstacles is discussed and the layout strategy of obstacles is optimized. The results show that the longitudinal obstacles in front of the exit can effectively play the diversion role of obstacles when the obstacle is at a certain distance from the exit, which will improve the evacuation efficiency of the blind. Furthermore, a horizontal obstacle of appropriate length can constrain the trajectory of the blind people and improve the efficiency of evacuation, but when the horizontal obstacle is too long, it will induce extra jam on both sides of the obstacle and hinder the evacuation of the blind. The finding can provide the theoretical basis for the blind people's organization, management and the optimization of evacuation strategies during an emergency. [ABSTRACT FROM AUTHOR]

The overtaking behavior of individuals under anxious panic is a major causative factor of crowded trampling accidents. In order to simulate the overtaking behavior of individuals experiencing anxiety and panic in a single-exit room within a normal pedestrian flow, an improved social force model is proposed to simulate crowd movement at local medium and high density through introducing the bypass overtaking mechanism, the side overtaking mechanism, and the side avoidance mechanism generated by association. The numerical simulation verifies the model's validity. The effect of the size and number of overtaking individuals on the pedestrian flow are explored. The results show that the new model can simultaneously reproduce a variety of overtaking behaviors and their associated behaviors in line with reality. The larger size of the overtaking individuals are, the easier it is to produce overtaking behaviors and the more difficult it is to overtake. With the increase of the number of overtaking individuals, the evacuation time becomes longer, but there is no linear relationship between them. When the initial pedestrian density is 0. 37 ped / m 2 , with time evolution, the appearance frequency of local density greater than 0. 8 ped / m 2 suddenly increases, and the comfort and safety of pedestrian movement decreases. The results of this paper can enrich the social force simulation model of pedestrian flow and provide a theoretical guidance for the evacuation of pedestrian flow with a few overtaking individuals in the room. • A novel social force model is used to describe individuals' overtaking behavior. • The overtaking mechanism and the side avoidance mechanism are introduced. • The effect of the size and number of overtaking individuals are explored. • The larger size of pedestrians are, the easier it is to produce overtaking behavior. [ABSTRACT FROM AUTHOR]

Recycled SiO2 micropowder solid waste (SiO2<85 mass%) was heat treated at 400,500,600,700,800,900, and 1 000 °C for 5 h, respectively, and then the heat treated powders were analyzed. The results show that the samples are gradually sintered as the heat treatment temperature increases. Below 800 °C, the original structure of granular and spherical SiO2 aggregates remains. However, at 500 °C or below, the aggregates strength is low. Above 800 °C, SiO2 micropowder agglomerates seriously and cristobalite is precipitated. When the heat treatment temperature is in the range of 600-800 °C, the spherical SiO2 micropowder with a certain strength and the bulk density of 0.73-0.95 g · cm-3 and a core-shell structure can be prepared, which can be used as a lightweight raw material for low temperature insulation castables and as a filler for other industries. [ABSTRACT FROM AUTHOR]