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Based on the slip line field theory, the slip line field model of roadway floor is established.Taking 1021 roadway of Huipodi coal mine in Shanxi Province as the engineering background, the mechanism of asymmetric floor heave of roadway is studied, and the reasonable prevention and control technology of floor heave is put forward.The results show that: There are uniform stress field and non-uniform stress field in the stress field of roadway floor slip line.From the two sides to the center line of the roadway, the floor stress decreases gradually; The velocity of the active zone of the floor slip line is vertical downward.The transition zone rotates and compresses the passive zone due to the extrusion of the active zone.The passive zone moves upward, resulting in floor heave.Due to the stress concentration of isolated pillar in Huipodi coal mine, the abutment pressure on both sides of the roadway is asymmetric.The abutment pressure near the coal pillar forms a slip line field on the floor, and the direction of the velocity field points to the side of the roadway far away from the pillar.Therefore, the floor heave of 1021 roadway is asymmetric, and the floor heave height at the side far away from the pillar is larger.According to the characteristics of sliding floor heave in 1021 roadway, asymmetric support with parallel arrangement of single anchor cable is adopted to prevent floor heave of roadway, and the application effect is good.

Mechanosensitive channels sense mechanical forces in cell membranes and underlie many biological sensing processes.sup.1-3. However, how exactly they sense mechanical force remains under investigation.sup.4. The bacterial mechanosensitive channel of small conductance, MscS, is one of the most extensively studied mechanosensitive channels.sup.4-8, but how it is regulated by membrane tension remains unclear, even though the structures are known for its open and closed states.sup.9-11. Here we used cryo-electron microscopy to determine the structure of MscS in different membrane environments, including one that mimics a membrane under tension. We present the structures of MscS in the subconducting and desensitized states, and demonstrate that the conformation of MscS in a lipid bilayer in the open state is dynamic. Several associated lipids have distinct roles in MscS mechanosensation. Pore lipids are necessary to prevent ion conduction in the closed state. Gatekeeper lipids stabilize the closed conformation and dissociate with membrane tension, allowing the channel to open. Pocket lipids in a solvent-exposed pocket between subunits are pulled out under sustained tension, allowing the channel to transition to the subconducting state and then to the desensitized state. Our results provide a mechanistic underpinning and expand on the 'force-from-lipids' model for MscS mechanosensation.sup.4,11. The authors report the structural characterization of the mechanically activated channel MscS in different membrane environments and show how the mechanosensation of MscS can be visualized., Author(s): Yixiao Zhang [sup.1] , Csaba Daday [sup.2] , Ruo-Xu Gu [sup.2] , Charles D. Cox [sup.3] [sup.4] , Boris Martinac [sup.3] [sup.4] , Bert L. de Groot [sup.2] , [...]

Based on the excellent piezoelectric properties of 0.7Pb(Mg1/3Nb2/3)O3–0.3PbTiO3 (PMN–PT) single crystals, a hole-doped manganite film/PMN–PT heterostructure has been constructed to achieve electric-field and light co-control of physical properties. Here, we report the resistivity switching behavior of Eu0.7Sr0.3MnO3/PMN–PT(111) multiferroic heterostructures under different in-plane reading currents, temperatures, light stimuli and electric fields, and discuss the underlying coupling mechanisms of resistivity change. The transition from the electric-field induced lattice strain effect to polarization current effect can be controlled effectively by decreasing the in-plane reading current at room temperature. With the decrease of temperature, the interfacial charge effect dominates over the lattice strain effect due to the reduced charge carrier density. In addition, light stimulus can lead to the delocalization of eg carriers, and thus enhance the lattice strain effect and suppress the interfacial charge effect. This work helps to understand essential physics of magnetoelectric coupling and also provides a potential method to realize energy-efficient multi-field control of manganite thin films. [ABSTRACT FROM AUTHOR]

Vehicle detection and location is one of the key sensing tasks of automatic driving systems. Traditional detection methods are easily affected by illumination, occlusion and scale changes in complex scenes, which limits the accuracy and robustness of detection. In order to solve these problems, this paper proposes a vehicle detection and location method for YOLOv5(You Only Look Once version 5) based on binocular vision. Binocular vision uses two cameras to obtain images from different angles at the same time. By calculating the difference between the two images, more accurate depth information can be obtained. The YOLOv5 algorithm is improved by adding the CBAM attention mechanism and replacing the loss function to improve target detection. Combining these two techniques can achieve accurate detection and localization of vehicles in 3D space. The method utilizes the depth information of binocular images and the improved YOLOv5 target detection algorithm to achieve accurate detection and localization of vehicles in front. Experimental results show that the method has high accuracy and robustness for vehicle detection and localization tasks. [ABSTRACT FROM AUTHOR]