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Following a burgeoning literature on private actors under digital authoritarianism, this study aims to understand the role played by social media users in sustaining authoritarian rule. It examines a subcultural community—the queer-fantasy community—on Chinese social media to expound how members of this community interpreted China's censorship policy, interacted based on the interpretation, and participated in censorship. Integrating structural topic modeling and emergent coding, this study finds that a political environment of uncertainty fostered divergent imaginaries about censorship. These imaginaries encouraged participatory censorship within the online community, which strengthened the political control of the Internet in the absence of the state. This study illuminates how participatory censorship works, especially in non-professional and non-politically mobilized online communities. With a focus on social media users, it also offers a lens for future research to compare peer-based surveillance and content moderation in authoritarian and democratic contexts. [ABSTRACT FROM AUTHOR]

Measuring the orientation, mass and body length of migratory insects through entomological radar is crucial for early warnings of migratory pests. The fully polarized entomological radar is an efficient device for observing migratory insects by calculating insect parameters through the scattering matrix obtained from the target. However, the measured target scattering matrix will be affected by system polarization measurement errors, leading to errors in insect parameter calculation, while the related analysis is currently relatively limited. Therefore, the scattering matrix measurement process is modeled, followed by an analysis of the effects of different errors on orientation, mass and body length estimation. The influence of polarization measurement errors on insect scattering characteristics is also analyzed. The results present that for fixed polarization measurement errors, the measurement errors of insect orientation, mass and body length will vary with insect orientation in specific patterns, and the distribution of measured insect parameters will be drastically distorted compared to the true parameter distribution. In addition, polarization measurement errors could seriously disrupt the reciprocity and bilateral symmetry of the measured insect scattering matrix. These analyses and conclusions provide a good basis for eliminating the effects of polarization measurement errors and improving the accuracy of insect parameter measurement. [ABSTRACT FROM AUTHOR]

Biochar is widely used as a soil amendment in green roofs because it can increase the soil's water-holding capacity, inhibit cracking, and provide nutrients for vegetation. The interaction mechanism between biochar and expansive soil is a significant factor in the performance of green roofs. However, research mainly focused on the hydrological scale (i.e. runoff regulation and rainwater storage), and there is a lack of research on the hydrological properties (i.e. hysteresis of soil–water characteristic curves, changes in soil pore size and pore distribution, formation and development of cracks and swelling–shrinking characteristics) of biochar-amended expansive soils under dynamic water environment. This test was conducted out on soil columns with expansive soil and 5% (by mass) biochar-amended under 5 drying–wetting cycles. The results showed that within the range of water content suitable for plant growth (i.e. between the anaerobic point and wilting point), the hysteresis area of soil–water characteristic curves of the amended soil is smaller than the bare soil at each drying–wetting cycle. The addition of biochar changes the pore size distribution of the soil, reduces the pore size and swelling–shrinking characteristics of the expansive soil, and inhibits the development of cracks. Therefore, the addition of biochar significantly attenuates the hysteresis characteristics of the soil–water characteristic curves of expansive soils, which may improve the stability of the hydraulic performance of green roofs. The results contribute to the understanding of the physicochemical and water properties of biochar-amended expansive soil and provide theoretical support for the application of biochar to green roofs. [ABSTRACT FROM AUTHOR]

Process analytical technology (PAT) plays a crucial role in optimizing crystalline powder product qualities, improving process stability, and reducing experimental costs by enabling real-time monitoring and control of process variables during the crystallization process. In-situ process imaging and analysis have gained significant attention due to their capacity to provide abundant information through images, leading to remarkable advancements in image processing technology, particularly with the support of artificial intelligence. However, the performance suffers when processing high-density slurry images due to challenges such as defocusing, overlapping, background and crystal edges blurriness, and inconsistencies in crystal scales. To address these challenges and explore research strategies based on deep learning for segmenting and analyzing high slurry density images effectively, this study constructed a specific dataset that contains high-density slurry crystal images which is well-labeled, and introduced state-of-the-art neural networks including YOLOv8, U2-net, and Mask R-CNN combined with image and data enhancement strategies. Comparative analysis revealed that YOLOv8 outperformed Mask R-CNN and U2-net by capturing multi-dimensional information in high-density crystal slurry scenarios. Finally, based on the segmentation results of the practical taurine crystallization process using proposed strategy, 1D crystal size, aspect ratio along with 2D size distributions were extracted for further evaluation of crystallization kinetics and crystal properties accurately and quickly. [Display omitted] • In-situ crystal micrograph of high slurry density image database was conducted. • The state-of-the-art networks were introduced to high-density scenarios. • High-density images were segmented in higher accuracy. • Multi-dimensional information was extracted more accurately using proposed deep-learning strategy. [ABSTRACT FROM AUTHOR]

The article focuses on proposing an efficient architecture, SMLP4Rec, for sequential recommendations, addressing issues in existing self-attention models and MLP4Rec. Topics include changing the cascading structure to parallel mode, integrating normalization layers for efficiency, and improving training speed and prediction accuracy compared to MLP4Rec.

Despite the recent surge in scholarly attention to anti‐Asian racism, what is largely missing in this growing body of literature is a bridge connecting studies on this subject to the broader field of race and ethnicity studies. In this special issue, we propose to use the concept of transculturality, which is defined as the process of cultural interaction, interpenetration, and hybridization that transcends the traditional borders of individual cultures, to establish this connection. In this introductory article, we first critically review the concepts of culture, interculturality, and multiculturality in the studies of race and ethnicity. Upon this review, we explain how transculturality advances the knowledge of racial and ethnic identity, ideas, and practices. This introduction concludes with an overview of each contribution, setting the stage for a comprehensive exploration of this complex and multifaceted issue. Collectively, this special issue aims to not only provide theoretical and empirical insights into the transculturality of anti‐Asian racism but also build a bridge between the studies of the Asian diaspora and the general research on race and ethnicity. [ABSTRACT FROM AUTHOR]

• Explore large deformation behaviors of layered rock tunnels under groundwater. • Experimental tests on mechanical behaviors of layered carbonaceous shales. • Groundwater effects on tunnel deformation and support responses are studied. • Analyze saturated softening effect by numerical simulations and field tests. • Large deformation and unsymmetrical load are alleviated by asymmetric rockbolts. Deep-buried tunnels constructed through layered soft rocks undergo large deformation, which threatens their safety and leads to construction delay. When a soft rock tunnel is excavated below the water table, the rock mass will deteriorate due to the presence of groundwater, aggravating the large deformation issue. In this work, the Baozhen tunnel excavated in layered carbonaceous shale was taken as a case study to investigate the mechanical behavior and support countermeasures of deep-buried tunnels with a high geostress considering the effect of groundwater. First, laboratory tests were performed to study the groundwater effect on the mechanical properties of the shale. Subsequently, the geological and large deformation characteristics of selected study areas using the original support scheme were analyzed. Using the tested constitutive parameters combined with the field-monitored deformation, a UDEC numerical model was established to investigate the tunnel deformation behavior under different bedding angles, groundwater depths, and shear stresses. Finally, the optimized support scheme was verified through numerical and on-site monitoring results. The tunnel responses at three typical monitoring cross-sections, such as the deformation distribution and normal pressures acting on the primary support and secondary lining, were compared to investigate the effect of groundwater and the optimized support scheme on the tunnel responses. An asymmetric large deformation was induced by the combined action of the soft layered rock and shearing action under the effect of groundwater. The groundwater reduced the rock strength and increased the tunnel deformation, and it also strengthened the unsymmetrical loading effect, which was reflected in the distributions of the tunnel deformation and support pressures. As a countermeasure, asymmetrically arranged rockbolts could help reduce the full-ring tunnel deformation and support pressure by 50.3 % and 22 %, respectively, which could also alleviate the unsymmetrical loading effect, thus enhancing the synergistic performance of the support structures. The insights gained in this study can help improve the effectiveness of countermeasures against layered rock instability while tunneling in the presence of groundwater. [ABSTRACT FROM AUTHOR]

The pursuit of an advanced functional coating that simultaneously combines high hardness, wear resistance, and superior electrical conductivity has remained an elusive goal in the field of copper alloy surface enhancement. Traditional solid solution alloying methods often lead to a significant increase in electron scattering, resulting in a notable reduction in electrical conductivity, making it challenging to achieve a balance between high hardness, wear resistance, and high conductivity. The key lies in identifying a suitable microstructure where dislocation motion is effectively hindered while minimizing the scattering of conductive electrons. In this study, a novel Cu-MoSi2 coating was successfully fabricated on a CuCrZr alloy surface using the coaxial powder feeding high-speed laser cladding technique, with the addition of 10–30% MoSi2 particles. The coating significantly enhances the hardness and wear resistance of the copper substrate while maintaining favorable electrical conductivity. As the quantity of MoSi2 particles increases, the coating's hardness and wear resistance gradually improve, with minimal variance in conductivity. Among the coatings, the Cu-30%MoSi2 coating stands out with the highest hardness (974.5 HV0.5) and the lowest wear amount (0.062 mg/km), approximately 15 times the hardness of the copper base material (65 HV0.5) and only 0.45% of the wear amount (13.71 mg/km). Additionally, the coating exhibits a resistivity of 0.173 × 10−6 Ω·m. The extraordinary hardness and wear resistance of these coatings can be attributed to the dispersion strengthening effect of MoxSiy particles, while the high electrical conductivity is due to the low silicon content dissolved into the copper from the released MoSi2 particles, as well as the rapid cooling rates associated with the high-speed laser cladding process. [ABSTRACT FROM AUTHOR]

Nb alloy has become a promising material in aerospace due to high melting point, low density and excellent processing properties. Nevertheless, the mismatched mechanical properties and thermal stability of single-phase BCC-Nb made the aircraft unable to resist cyclic vibration loads under the action of heat/force/flow. Here, after solid solution, quenching and two-stage aging, an FCC/BCC dual-phase Nb alloy with a discontinuous grain boundary (GB) carbide network skeleton was formed. The results show that interstitial C atoms precipitate from BCC-Nb matrix resulting in volume shrinkage and form discontinuous carbide at GB, which stimulates the phase transition of BCC expansion to FCC near GB. Wherein, discontinuous GB carbides help pin the GB and dislocations, impede grain growth, and change the deformation from local to the entire network skeleton. Meanwhile, the gap provides a channel for the dislocation to pass through the GB. Additionally, the FCC provides the multi-slip system to transfer the dislocation. The results show that the yield strength, tensile strength, elongation, fracture toughness and elastic modulus of Nb alloy are increased by 79.99 %, 34.52 %, 164.22 %, 204.76 % and 1.27 %, respectively. This unique microstructure is expected to guide the design of the next generation of high-performance Nb alloys. [ABSTRACT FROM AUTHOR]