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The interfacial transition zone (ITZ) has long been considered as a zone of weakness in concrete. Many scholars have carried out relatively scattered tentative explorations to improve the performance of ITZ. The application of nanomaterials to enhance ITZ in concrete is a promising research. In order to further study the basic principles and practical applications of this field, it is urgent to systematically sort out the existing results. In this study, the nano-modification of ITZ in concrete is systematically reviewed and summarized. First, this study reviews the microscopic characterization of ITZ, including hydration products, porosity, and microhardness. Then, the influence of nanomaterials on ITZ is reviewed from the view of the above three aspects. Finally, the method and mechanism of the ITZ modified by nanomaterials were preliminarily clarified, which provided theoretical and empirical data support for the team’s next experimental work. A large number of research results show that nanomaterials improve the mechanical properties and microstructure of the ITZ, thus enhancing the mechanical properties and durability of concrete. The results of this article will provide source materials for the development of this field, a broader research basis for peer research, and a basis for further development of green engineering materials.

Filter membranes are the core components of the solid–liquid separation equipment, and their control over particulate pollutants directly determines the effective operation of the system. The feeding of the balaenid whales, acting as an "oral filter," provides new technical ideas for the design of traditional filter membranes. This study proposes a 3-input, 9-output UNet deep learning framework and applies it to rapid flow field prediction in patterned baleen membranes of balaenid whales during filter feeding, named UNet-BaleenCFD. The datasets are obtained through computational fluid dynamics (CFD) simulations combined with linear interpolation, and the model is validated for the effectiveness against the revised theoretical model. To account for the differences in units and magnitudes of velocity and pressure, dimensionless velocity and pressure values are calculated in the loss function. Compared to the traditional CFD, UNet-BaleenCFD can accelerate by three orders of magnitude. Additionally, the predictions made by UNet-BaleenCFD are in good agreement with the results from CFD, indicating that UNet-BaleenCFD is a promising method for predicting flow fields in filter channels. This study can provide effective theoretical guidance for the development of new filter membranes. [ABSTRACT FROM AUTHOR]

The purpose of this research is to compare clustering methods and pick up the optimal clustered approach for rural building energy consumption data. Research undertaken so far has mainly focused on solving specific issues when employing the clustered method. This paper concerns Yushan island resident's time-series electricity usage data as a database for analysis. Fourteen algorithms in five categories were used for cluster analysis of the basic data sets. The result shows that Km_Euclidean and Km_shape present better clustering effects and fitting performance on continuous data than other algorithms, with a high accuracy rate of 67.05% and 65.09%. Km_DTW is applicable to intermittent curves instead of continuous data with a low precision rate of 35.29% for line curves. The final conclusion indicates that the K-means algorithm with Euclidean distance calculation and the k-shape algorithm are the two best clustering algorithms for building time-series energy curves. The deep learning algorithm can not cluster time-series-building electricity usage data under default parameters in high precision. [ABSTRACT FROM AUTHOR]

Drawing inspiration from the intricate soft structures found in nature, soft actuators possess the ability to incrementally execute complex tasks and adapt to dynamic and interactive environments. In particular, the integration of sensor data feedback allows actuators to respond to environmental stimuli with heightened intelligence. However, conventional rigid sensors are constrained by their inherent lack of flexibility. The current manufacturing processes for flexible sensors are complex and fail to align with the inherent simplicity of soft actuators. In this study, to facilitate the straightforward and consistent sensing of soft pneumatic actuators, carbon–polydimethylsiloxane (CPDMS) materials were employed, utilizing 3D printing and laser-cutting techniques to fabricate a flexible sensor with ease. The preparation of standard tensile specimens verified that the sensor exhibits a fatigue life extending to several hundred cycles and determined its gauge factor to be −3.2. Experimental results indicate that the sensor is suitable for application in soft pneumatic actuators. Additionally, a printed circuit board (PCB) was fabricated and the piecewise constant curvature (PCC) kinematic method was utilized to enable real-time pose estimation of the soft pneumatic actuator. Compared with computer vision methods, the pose estimation error obtained by the sensing method is as low as 4.26%. This work demonstrates that this easily fabricated sensor can deliver real-time pose feedback for flexible pneumatic actuators, thereby expanding the potential application scenarios for soft pneumatic actuators (SPAs). [ABSTRACT FROM AUTHOR]

Swifts, a distinctive avian cohort, have garnered widespread attention owing to their exceptional flight agility. While their aerial prowess is well documented, the challenge swifts encounter while imbibing water introduces an intriguing complexity. The act of water uptake potentially disrupts their flight equilibrium, yet the mechanisms enabling these birds to maintain stability during this process remain enigmatic. In this study, we employed high-speed videography to observe swifts' water-drinking behavior. Notably, we observed that the swift adopts a dynamic V-shaped wing configuration during water immersion with the ability to modulate the V-shaped angle, thereby potentially fine-tuning their balance. To delve deeper, we utilized a three-dimensional laser scanner to meticulously construct a virtual 3D model of swifts, followed by computational fluid dynamics simulations to quantitatively assess the mechanical conditions during foraging. Our model indicates that the adoption of V-shaped wings, with a variable wing angle ranging from 30 to 60 degrees, serves to minimize residual torque, effectively mitigating potential flight instability. These findings not only enhance our comprehension of swifts' flight adaptability but also hold promise for inspiring innovative, highly maneuverable next-generation unmanned aerial vehicles. This research thus transcends avian biology, offering valuable insights for engineering and aeronautics. [ABSTRACT FROM AUTHOR]

In order to explore the engineering application potential of coal gangue-based geopolymer concrete (CGGPC), this article formulated the fiber-reinforced coal gangue-based geopolymer concrete (FRCGGPC). The mechanical properties of the specimens were tested to analyze the effects of different types and dosing amounts of fibers on the mechanical properties of CGGPC. The microscopic morphology of the specimens was observed by scanning electron microscopy (SEM) to analyze the strengthening mechanism of fibers on the mechanical properties of the CGGPC. The experimental results show that the splitting tensile strength of FRCGGPC can be improved obviously, but the improvement of compressive strength is not obvious. The control groups containing steel fiber (SF) and polyester fiber (PF) had peaks in their compressive strength. Under the same dosage, the effect of SF and PF on the splitting tensile strength of FRCGGPC is better than basalt fiber. The results of SEM analysis show that within a certain range of dosage, the fiber is closely combined with the matrix, which has a good force transmission effect and strengthens the matrix material. When the fiber dosage is too much, it is easy to agglomerate, which leads to the decrease in the mechanical properties of the specimens.