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The rebar installation quality significantly impacts the safety and durability of reinforced concrete (RC) structures. Traditional manual inspection is time-consuming, inefficient, and highly subjective. In order to solve this problem, this study uses a depth camera and aims to develop an intelligent inspection method for the rebar installation quality of an RC slab. The Random Sample Consensus (RANSAC) method is used to extract point cloud data for the bottom formwork, the upper and lower rebar lattices, and individual rebars. These data are utilized to measure the concrete cover thickness, the distance between the upper and lower rebar lattices, and the spacing between rebars in the RC slab. This paper introduces the concept of the "diameter calculation region" and combines point cloud semantic information with rebar segmentation mask information through the relationship between pixel coordinates and camera coordinates to measure the nominal diameter of the rebar. The verification results indicate that the maximum deviations for the concrete cover thickness, the distance between the upper and lower rebar lattices, and the spacing of the double-layer bidirectional rebar in the RC slab are 0.41 mm, 1.32 mm, and 5 mm, respectively. The accuracy of the nominal rebar diameter measurement reaches 98.4%, demonstrating high precision and applicability for quality inspection during the actual construction stage. Overall, this study integrates computer vision into traditional civil engineering research, utilizing depth cameras to acquire point cloud data and color results. It replaces inefficient manual inspection methods with an intelligent and efficient approach, addressing the challenge of detecting double-layer reinforcement. This has significant implications for practical engineering applications and the development of intelligent engineering monitoring systems. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) is widely used in many research fields because of its excellent properties. The femtosecond laser has been proven to be an effective method for achieving high-quality and high-efficiency SiC micromachining. In this article, the ablation mechanism irradiated on different surfaces of 6H-SiC by a single pulse under different energies was investigated. The changes in material elements and the geometric spatial distribution of the ablation pit were analyzed using micro-Raman spectroscopy, Energy Dispersive Spectrum (EDS), and an optical microscope, respectively. Moreover, the thresholds for structural transformation and modification zones of 6H-SiC on different surfaces were calculated based on the diameter of the ablation pits created by a femtosecond laser at different single-pulse energies. Experimental results show that the transformation thresholds of the Si surface and the C surface are 5.60 J/cm2 and 6.40 J/cm2, corresponding to the modification thresholds of 2.26 J/cm2 and 2.42 J/cm2, respectively. The Raman and EDS results reveal that there are no phase transformations or material changes on different surfaces of 6H-SiC at low energy, however, decomposition and oxidation occur and then accumulate into dense new phase material under high-energy laser irradiation. We found that the distribution of structural phase transformation is uneven from the center of the spot to the edge. The content of this research reveals the internal evolution mechanism of high-quality laser processing of hard material 6H-SiC. We expect that this research will contribute to the further development of SiC-based MEMS devices. [ABSTRACT FROM AUTHOR]

This paper presents an actuated spring-loaded inverted pendulum model with a vertically constrained suspended load mass to predict the vertical GRF and energetics of walking and running. Experiments were performed to validate the model prediction accuracy of vertical GRF. The average correlation coefficient was greater than 0.97 during walking and 0.98 during running. The model's predictions of energy cost reduction were compared with experimental data from the literature, and the difference between the experimental and predicted results was less than 7%. The predicted results of characteristic forces and energy cost under different suspension stiffness and damping conditions showed a tradeoff when selecting the suspension parameters of elastically suspended backpacks. [ABSTRACT FROM AUTHOR]

Individual‐based morphological brain networks built from T1‐weighted magnetic resonance imaging (MRI) reflect synchronous maturation intensities between anatomical regions at the individual level. Autism spectrum disorder (ASD) is a socio‐cognitive and neurodevelopmental disorder with high neuroanatomical heterogeneity, but the specific patterns of morphological networks in ASD remain largely unexplored at the individual level. In this study, individual‐based morphological networks were constructed by using high‐resolution structural MRI data from 40 young children with ASD (age range: 2–8 years) and 38 age‐, gender‐, and handedness‐matched typically developing children (TDC). Measurements were recorded as threefold. Results showed that compared with TDC, young children with ASD exhibited lower values of small‐worldness (i.e., σ) of individual‐level morphological brain networks, increased morphological connectivity in cortico‐striatum‐thalamic‐cortical (CSTC) circuitry, and decreased morphological connectivity in the cortico‐cortical network. In addition, morphological connectivity abnormalities can predict the severity of social communication deficits in young children with ASD, thus confirming an associational impact at the behavioral level. These findings suggest that the morphological brain network in the autistic developmental brain is inefficient in segregating and distributing information. The results also highlight the crucial role of abnormal morphological connectivity patterns in the socio‐cognitive deficits of ASD and support the possible use of the aberrant developmental patterns of morphological brain networks in revealing new clinically‐relevant biomarkers for ASD. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increasing demand for portable power sources as people are required to carry more equipment for occupational, military, or recreational purposes. The energy harvesting backpack that moves relative to the human body, could capture kinetic energy from human walking and convert vertical oscillation into the rotational motion of the generators to generate electricity. In our previous work, a light-weight tube-like energy harvester (TL harvester) and a traditional frequency-tuneable backpack-based energy harvester (FT harvester) were proposed. In this paper, we discuss the power generation performance of the two types of energy harvesters and the energy performance of human loaded walking, while carrying energy harvesting backpacks, based on two different spring-mass-damper models. Testing revealed that the electrical power in the experiments showed similar trends to the simulation results, but the calculated electrical power and the net metabolic power were higher than that of the experiments. Moreover, the total cost of harvesting (TCOH), defined as additional metabolic power in watt required to generate 1 W of electrical power, could be negative, which indicated that there is a chance to generate 6.11 W of electricity without increasing the metabolic cost while carrying energy harvesting backpacks. [ABSTRACT FROM AUTHOR]

Backpacks are essential for travel but carrying a load during a long journey can easily cause muscle fatigue and joint injuries. Previous studies have suggested that suspended backpacks can effectively reduce the energy cost while carrying loads. Researchers have found that adjusting the stiffness of a suspended backpack can optimize its performance. Therefore, this paper proposes a stiffness-adjustable suspended backpack; the system stiffness can be adjusted to suitable values at different speeds. The stiffness of the suspended backpack with a 5-kg load was designed to be 690 N/m for a speed of 4.5 km/h, and it was adjusted to 870 and 1050 N/m at speeds of 5.5 and 6.5 km/h, respectively. The goal of this study was to determine how carrying a stiffness-adjustable suspended backpack affected performance while carrying a load. Six healthy participants participated in experiments where they wore two backpacks under three conditions: the adjustable-stiffness suspended backpack condition (S_A), the unadjustable-stiffness suspended backpack condition (S_UA), and the ordinary backpack condition (ORB). Our results showed that the peak accelerations, muscle activities, and peak ground reaction forces in the S_A condition were reduced effectively by adjusting the stiffness to adapt to different walking speeds; this adjustment decreased the metabolic cost by 4.21 ± 1.21% and 2.68 ± 0.88% at 5.5 km/h and 4.27 ± 1.35% and 3.38 ± 1.31% at 6.5 km/h compared to the ORB and S_UA, respectively., (Copyright © 2022 by ASME.)