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The realization of intelligent mine ventilation is the main technical means to build intelligent mines. Aiming at the problems of inaccurate adjustment of the ventilation system, low level of intelligence, and early warning information to be reflected in the emergency and disaster relief command center, a construction scheme of mine intelligent ventilation system was proposed. The scheme consists of underground monitoring equipment and a ground control center. It aims to establish a 3D ventilation simulation and intelligent identification platform for hidden dangers, and realize real-time dynamic analysis of mine ventilation data, 3D visualization, and safety early warning and auxiliary decision-making. Five key technologies of ventilation monitoring database, 3D ventilation simulation, AI video intelligent recognition, early warning and auxiliary decision-making, and system linkage control were studied in detail, and their technical characteristics and implementation plans were elaborated. Based on computer software development technology, 3D simulation technology and artificial intelligence technology, the mine intelligent ventilation system is designed and developed.

Chronic non-specific neck pain (CNNP) poses a substantial health and economic burden in China. This study introduces a gamified motion-sensing health application framework to address the limitations of existing health applications. The gamified cervical spine somatic exercise application employs motion capture technology alongside the smartphone's built-in sensors to simulate accurate somatic interactions. Controlled experiments and data analyses demonstrated that the application significantly outperformed traditional text and video interventions in relieving participants' neck pain by increasing their average daily activity and compliance with the cervical spine exercise routine. The neck pain level of the participants is quantified by the Neck Disability Index (NDI). The results from the controlled experiments demonstrate that this gamified approach significantly decreases the Neck Disability Index (NDI) score from 1.54 to 1.24, highlighting its ability to alleviate neck pain and increase user compliance. [ABSTRACT FROM AUTHOR]

In order to effectively regulating the deformation behavior of aluminum alloy sheet in electromagnetic forming processes of track coil, the influences of the relative position of the sheet metal and the coil assembly on the electromagnetic force, current density, deformation velocity and forming height were revealed by experimental-simulation and theoretical calculation. An engineering calculation model of the magnetic induction intensity in central plane of the coil was derived. With the increase of the offset in sheet assembly, the maximum height difference of the deformation zone of the electromagnetic forming specimen gradually decreases, and the specimen changes from "low inside and high outside" to "high outside and low inside". The peak electromagnetic force density moves from the inside of the sheet metal to the center. When the offset amount is as 2.5~3.0 mm, there is a minimum value for the height difference between the two sides. When the offset is as 3.0 mm, the lateral deformation speed of the sheet metal tends to be 0, and the electromagnetic force is axisymmetrically distributed along the center of the sheet. Based on the engineering model of the magnetic induction intensity of the track coils, the relationship among the position of the symmetrical center region f magnetic inductance and the half length of the straight section of the coil, the turn spacing, the enter distance the sheet assembly clearance was deduced, and the optimal offset is as 2.2~3.9 mm. This results are consistent with the simulation experimental ones and confirm the reliability of the model. [ABSTRACT FROM AUTHOR]

Potassium niobate (KNbO3, KNO) has been intensively investigated for photovoltaic performance because of its non-toxicity and excellent nonlinear optical properties. The corresponding photovoltaic current density, however, remains very low due to a wide bandgap. Chemical doping and strain engineering strategies have been employed to tailor the band structure to enhance photovoltaic current density. Nevertheless, the original current density is still at a level of several tens of nA/cm2, significantly limiting device applications. In this work, we report a lattice-gradient KNO film on (100) single-crystal 0.7 wt. % Nb doped SrTiO3 (NSTO) substrate processed by annealing, generating a polarization-gradient that allows us to generate a large current density via a built-in field. The film exhibits a remarkable short-circuit current density (Jsc) of 58.63 µA/cm2 under the 375 nm irradiation of 500 mW/cm2 light intensity, where the corresponding responsivity (117.26 µA/W) is ∼3.82 times higher than those of reported KNO-based materials. It was revealed that the annealing process driven interfacial structure evolution from disorder to atomic-scale smoothness, accompanied by the transformation of the polarization shielding mechanism. After this process, an intriguing lattice-gradient throughout the film was established to have a uniform polarization direction, possibly accounting for the improved photovoltaic current density of KNO film. These findings may trigger interest in developing KNO as a potential key material for lead-free optoelectronic or photodetector devices. [ABSTRACT FROM AUTHOR]

The article reports that the COVID-19 pandemic become an enduring reality that all countries must learn to live with. Topics include examines that the transformation of the international political and economic system in the post-pandemic era has led to increasing uncertainty, which further complicates the evolution of underlying structural factors such as power distribution and prevailing norms.