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Stripe images are crucial for ensuring the measurement quality of line-structured light sensors. To improve the measurement effectiveness of objects with different shapes, materials, and colors, an adaptive exposure method is proposed based on global grayscale statistical analysis of stripe images. The logarithm sum of grayscale statistical results is calculated as the quality evaluation parameter for each stripe image. Theoretical analysis and experiments demonstrate that the proposed quality evaluation value exhibits an approximate linear relationship with a camera’s exposure time. Subsequently, an adaptive exposure control method is developed. The influence of control system parameters on measurement results is also analyzed in detail. The experimental results show that our method can adaptively adjust a camera’s exposure time according to different surface characteristics. Both the number of effective measurement points and the accuracy are improved.

For vertical takeoff and landing (VTOL) control of distributed-propulsion, fixed-wing UAVs exhibiting strong nonlinearity and aerodynamic/propulsive coupling, traditional linearization methods incur significant modeling errors in pitch–roll coupling and vortex interference scenarios due to neglected high-order nonlinearities, leading to inherent control law limitations. This study focuses on a non-tilting, distributed-propulsion VTOL UAV featuring integrated airframe-propulsion design. Each of its four propulsion units contains six ducted rotors, arranged in tandem wing configuration on both fuselage sides. A revised propulsion–aerodynamic coupling model was established and validated through bench tests and CFD data, enabling the design of an Incremental Nonlinear Dynamic Inversion (INDI) control architecture. The UAV dynamics model was constructed in Matlab/Simulink incorporating this revised model. An INDI-based attitude control law was developed with cascade controllers (angular rate inner-loop/attitude outer-loop) for VTOL mode, integrated with propulsion-system and control-surface allocation strategies. Digital simulations validated the controller’s effectiveness and robustness. Finally, tethered flight tests with physical prototypes confirmed the method’s applicability for high-precision control of strongly nonlinear distributed-propulsion UAVs.

The integration of propulsion and wing in distributed propulsion–wing UAVs (DPW UAVs) introduces significant propulsion-aerodynamic coupling, complicating dynamic modeling and flight control. This complexity is heightened by using induced wing surfaces for vertical takeoff and landing, requiring controllers to adapt to configuration changes and disturbances during transition flight. This paper develops a propulsion-aerodynamic coupling model for a medium-sized DPW UAV with induced wings (DPW-IW), enabling real-time aerodynamic performance calculations. Furthermore, a unified flight-control framework is proposed to avoid controller scheduling and switching during flight mode transitions. The proposed control framework employs the time-scale separation principle, divided into an outer loop and an inner loop. The outer loop uses a fuzzy controller to adjust allocation parameters, while the inner loop applies incremental nonlinear dynamic inversion (INDI) and control allocation (INCA) methods, providing robustness to nonlinear changes during flight transitions. Finally, simulations under various conditions demonstrate the controller’s effectiveness in ensuring smooth and robust transitions.

The frame field distributed inside the model region characterizes the singular structure features inside the model. These singular structures can be used to decompose the model region into multiple quadrilateral structures, thereby generating a block-structured quadrilateral mesh. For the generation of block-structured quadrilateral mesh for two-dimensional geometric models, a convolutional neural network model is proposed to identify the singular structure inside the model contained in the frame field. By training the network model with a large number of model region decomposition data obtained in advance, the model can identify the vectors of the frame field in the region located in the segmentation field. Then, the segmentation streamline is constructed from the annotation. Based on this, the geometric region is decomposed into several small regions, regions which are then discretized with quadrilateral mesh elements. Finally, through two geometric models, it is verified that the convolutional neural network model proposed in this study can effectively identify the singular structure inside the model to realize the model region decomposition and block-structured mesh generation.

Astragalus membranaceus and Codonopsis pilosula are widely used in traditional chinese medicine for the treatment of diabetes because of their notable hypoglycemic pharmacological effects. Studies have indicatedthat the active compounds in the Astragalus-Codonopsis herb pair may exert their hypoglycemic effects through the modulation of the insulin receptor (IRSP) signaling pathway. In this study, the rhamnolitrin and folic acid were confirmed as the key active components in the Astragalus-Codonopsis herb pair that regulate the IRSP, with their synergistic mechanisms in Type 2 Diabetes Mellitus (T2DM) being further systematically explored by network pharmacology combined with DFT theoretical calculation, molecular docking, molecular dynamics simulation and alanine scanning mutation technology. The results suggest that GSK3β is a critical target through which rhamnolitrin and folic acid exert their anti-diabetic effects. Subsequent molecular docking and molecular dynamics simulations confirmed that both active compounds selected in this study can bind stably with the GSK3β protein. Further alanine scanning mutagenesis experiments validated the importance of key amino acid residues in ligand-receptor interactions. Finally, DFT theoretical calculations provided a detailed elucidation of the binding mechanism between the core components (rhamnolitrin and folic acid) and the target protein GSK3β. This study not only revealed the molecular mechanism of Astragalus-Codonopsis for the treatment of type 2 diabetes, provided a theoretical basis for its clinical application, but also provided a potential molecular target for the development of new anti-diabetes drugs.

From rotational potential vorticity-conserved equation with topography effect and dissipation effect, with the help of the multiple-scale method, a new integro-differential equation is constructed to describe the Rossby solitary waves in deep rotational fluids. By analyzing the equation, some conservation laws associated with Rossby solitary waves are derived. Finally, by seeking the numerical solutions of the equation with the pseudospectral method, by virtue of waterfall plots, the effect of detuning parameter and dissipation on Rossby solitary waves generated by topography are discussed, and the equation is compared with KdV equation and BO equation. The results show that the detuning parameter α plays an important role for the evolution features of solitary waves generated by topography, especially in the resonant case; a large amplitude nonstationary disturbance is generated in the forcing region. This condition may explain the blocking phenomenon which exists in the atmosphere and ocean and generated by topographic forcing.

Automatic generation of hexahedral meshes for complex geometries is still a challenging problem, the domain-decomposition based method is one of the promising methods for such problems. When generating the meshes of sub-components of a domain, it is often necessary to impose consistent mesh constraints on the interfaces between sub-components. The adoption of mesh matching algorithms can relax such constraints, and improve the efficiency and robustness of mesh generation framework. In this paper, a new mesh matching algorithm based on base-complex structure is proposed. In our method, the base-complex structures of the sub-components to be matched are obtained and optimized first, and then they are used to match the interfaces between the sub-components via dual chord operations on the base-complex structures. After the matching process, an optimization problem is formulated and solved to adjust the positions of corresponding vertices on the interfaces. Compared to the current mesh matching algorithms, instead of performing dual operations directly on mesh elements, the proposed method needs less dual operations and is able to obtain higher quality elements near the interfaces. Finally, the effectiveness of the proposed algorithm is verified by several matching examples.

Nanocomposites of Ag with organic montmorillonite (Ag-OMMT), Ag with montmorillonite (Ag-MMT), and organic montmorillonite (OMMT) were successfully prepared via a one-step solution-intercalated method. Sodium MMT, silver nitrate, and dimethyl octadecyl hydroxy ethyl ammonium nitrate were used as precursors. X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, and energy dispersive spectroscopy analyses confirmed that the MMT layers were intercalated, and Ag+ was partly reduced to silver nanoparticles with diameters within 10–20 nm in Ag-OMMT. The decomposition temperature of the organic cations in OMMT and Ag-OMMT increased to 220°C, as revealed by differential scanning calorimetry-thermogravimetric analysis. The antimicrobial activity of the nanocomposites was tested by measuring the minimum inhibitory concentration (MIC) and killing rate. The MICs of Ag-OMMT against Staphylococcus aureus, Escherichia coli, and Candida albicans were 0.313, 2.5, and 0.625 mg/mL, respectively. Because of the presence of quaternary ammonium nitrate, Ag-OMMT has a better MIC against Gram-positive bacteria compared to Gram-negative bacteria and fungi. OMMT did not show antimicrobial activity against Escherichia coli and Candida albicans. In 2 h, 0.0125 mg/mL Ag-OMMT could kill 100% of S. aureus, E. coli, and C. albicans in solution, and Ag-MMT could kill 99.995% of S. aureus, 90.15% of E. coli, and 93.68% of C. albicans. These antimicrobial functional nanocomposites have the potential for application in the area of surface decoration films.

Due to its excellent comprehensive performances, Al-Si-Mg alloy i widely used in automotive, transportation and other fields. In this work, tensile performances and fracture behavior of Al-Si-Mg alloy modified by dilute Sc and Sr elements (Al-7.12Si-0.36Mg-0.2Sc-0.005Sr) were investigated at the temperature of −60–200 °C for the first time, aiming to obtain a satisfactory thermal stability within a certain temperature range. The results showed that the new designed Al-Si-Mg alloy possessed a completely stable yield strength and a higher-level elongation under the present conditions. Fracture morphology analysis, fracture profile observation and strengthening mechanism analysis were applied to elucidate the evolution mechanisms of yield strength and elongation of the alloy. The fracture modes were significantly distinct in different temperature sections, and the reasons were discussed. In addition, the interaction among the nano precipitate phase particles, the deformation substructure and the dislocations were responsible for the thermal stability of the alloy within a certain temperature range.

Combination therapy is a promising cancer treatment strategy that is usually based on the utilization of complicated nanostructures with multiple components functioning as photo-thermal energy transducers, photo-sensitizers, or dose intensifiers for phototherma! therapy （PTT）, photodynamic therapy （PDT）, or radiation therapy （RT）. In this study, ultrathin tungsten oxide nanowires （W18O49） were synthesized using a solvothermal approach and examined as a multifunctional theranostic nanoplatform. In vitro and in vivo analyses demonstrated that these nanowires could induce extensive heat- and singlet oxygen-mediated damage to cancer cells under 980 nm near infrared （NIR）-laser excitation. They were also shown to function as radiation dose intensifying agents that enhance irradiative energy deposition locally and selectively during radiation therapy. Compared to NIR-induced PTT/PDT and RT alone, W18O49 - based synergistic tri-modal therapy eradicated xenograft tumors and no recurrence was observed within a 9-month follow up. Moreover, the strong X-ray attenuation ability of the tungsten element （Z = 74, 4.438 cm^2·g^-1, 100 KeV） qualified these nanowires as excellent contrast agents in X-ray-based imaging, such as diagnostic computed tomography （CT） and cone-beam CT for image-guided radiation therapy. Toxicity studies demonstrated minimal adverse effects on the hematologic system and major organs of mice within one month. In conclusion, these nanowires have shown significant potential for cancer therapy with inherent image guidance and synergistic effects from phototherapy and radiation therapy, which warrants further investigation.