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Assistive technologies can improve greater participation in society and sociocultural experiences. A communication device for deafblind persons, called Caeski, is an assistive technology that allows independent communication between two deafblind persons or between deafblind and non-deafblind persons using vibrating keys. The aim of this study is to analyze the effects of hand-arm vibrations (HAV) emitted by Caeski to check if this will be harmful to users. The vibrations emitted by the Caeski’s keys were analyzed from data provided by a triaxial accelerometer, positioned over the fingers of a sample of seven deafblind individuals. The obtained data are within acceptable limits set by International Health and Safety standards – ISO 8041, ISO 5349-1 and European Directive 2002/44/EC – on the physical risk of vibration. Safety is part of the product development process. It was possible to demonstrate that the proposed technology is not harmful to users and can be used safely.

This study explores additive manufacturing's potential in creating tailored assistive technologies, fostering inclusion in education. To design ergonomic solutions for diverse user needs, promoting inclusion and autonomy. A sequential approach involves assessment, 3D modeling, additive manufacturing, and aligning with the Inclusion Support and Accessibility Promotion Program (PIPA). Various assistive technologies were developed, addressing specific needs. The “Ergonomic Pen and Pencil Reamer” improves grip accuracy, and the “Folding Handle for Folding Cup” offers an ergonomic solution. The “Guideline Ruler” supports music education, with accessories like the “Template for Clefs and Musical Notes” and “Thimble with Support Base for Musical Instrument Strings” enhancing versatility. The “Ring with Front Support” aids art education, and the “Support for Scissors” promotes independence. These innovations contribute to inclusion and autonomy. The research underscores the importance of additive manufacturing in crafting personalized solutions, propelling inclusion in education and daily activities. Identified challenges, including material selection and adaptation to diverse needs, signal areas for future research. Continuous collaboration with end-users and professionals remains crucial for enhancing usability and effectiveness, reinforcing the commitment to promoting inclusion and autonomy.

Daytime sleepiness (DS) often accompanies obstructive sleep apnea (OSA), exacerbating its effects. DS can impair cognitive function, attention, reaction time, and motor coordination, increasing the risk of accidents. This study aimed to explore the relationship between DS, changes in gait and balance, and the occurrence of orofacial fractures. A narrative review was conducted using PubMed, Scopus, and Web of Science publications. The analysis revealed the impact of DS and OSA on gait and balance control in older individuals, emphasizing the need for interventions to address these issues and identify associated pathologies. Continuous Positive Airway Pressure (CPAP) therapy was recognized as a potential treatment, although further research is needed to understand DS triggers and treatment options in older populations. The study underscores the importance of analyzing interactions between the central nervous system, medications, balance, and mobility to prevent falls and related injuries. While the literature highlights the vulnerability of elderly individuals and those with OSA to falls, no established link between DS, gait, balance, and orofacial trauma necessitating medical and dental intervention was found. Thus, further research is warranted to address this gap and promote better understanding and management of these conditions.

The fault data for Planetary Roller Screw Mechanisms (PRSM) is challenging to collect in real industrial settings due to the complex nature of practical operations and the lengthy accumulation period. Consequently, there has been little research on PRSM fault diagnosis. Additionally, the high processing cost of PRSM means that institutions are reluctant to make their fault data publicly available, creating a data barrier and further hindering research of the study on fault diagnosis of PRSM. To address these issues, Federated Learning (FL) is applied for PRSM fault diagnosis. In the FL framework, data remains in local storage, preserving data privacy. To reduce transmission costs, a lightweight model called SResNet18 is proposed. SResNet18 reduces parameters by 95.07 % and 61.93 % compared to ResNet18 and DSResNet18, respectively, which decreases the time needed for parameter uploading, model aggregation, and parameter returning. Additionally, SResNet18 has lower computational complexity, with 92.09 % and 36.66 % fewer FLOPs than ResNet18 and DSResNet18, respectively. Healthy and fault data of PRSM are collected on the PRSM testing rig, and the proposed method is evaluated. Results show that our method achieves the highest accuracy of 99.17 %, improving model performance while maintaining data privacy. The proposed SResNet18 also alleviates overfitting and reduces training time in the FL framework.

In response to the significant challenges posed by strong non-stationarity and the vulnerability to intense background noise in rolling bearing signals, as well as the inherent limitations of conventional convolutional neural networks (CNN) when processing one-dimensional (1D) signals without fully leveraging the inter-data relationships, this study introduces an innovative diagnostic approach for rolling bearings. The method employs the Time-Reassigned Multi-Synchro Squeezing Transform (TMSST) to preprocess 1D vibration signals. By harnessing the temporal correlations across various intervals, TMSST generates a set of time-frequency feature maps that are subsequently fed into a CNN to adaptively extract and classify the fault characteristics of rolling bearings. To substantiate the efficacy of the proposed model, the Case Western Reserve University's bearing dataset serves as the benchmark for the fault diagnosis analysis. Moreover, the study incorporates several alternative data processing techniques for comparative evaluation of the classification accuracy. The findings reveal that the proposed model, when juxtaposed with other image encoding methods, consistently delivers superior diagnostic performance across a spectrum of load conditions and noise environments. It achieves an impressive global accuracy of 95.67 %, thereby facilitating robust end-to-end fault pattern recognition in rolling bearings.

An alternative method to determine the average particle size of suspensions, from the loss of moisture as function of the time is presented. Consequently, the novelty of the method consists of determining the particle size through weight loss. According to this definition, these bulk variations are collected, by controlling at the same time, parameters as the relative dampness of the chambers and the temperature of the samples under analysis. Additionally, the data are processed in the time domain and Fourier-analyzed to obtain the average particle size. Statistically, the method was calibrated through the comparison with samples previously characterized by transmission electron microscopy, by using polymer latex dispersed in water with an average particle size of 24, 44, 74 and 105 µm.

Drilling and blasting method is still an important method in the current tunnel excavation construction. Controlling the vibration effect of blasting during construction and its influence on the upper span tunnel is the key problem in tunnel construction. Based on Chongqing Science City tunnel excavation blasting project, combined with the tunnel blasting vibration monitoring and testing, this paper analyzes the propagation attenuation law of tunnel blasting vibration along the rock mass, and studies the load characteristics of the explosion stress wave propagating to the existing high-speed railway tunnel. Considering the influence of the buried depth of the blasting source, a mathematical prediction model of the attenuation law of the upper span existing high-speed railway tunnel caused by tunnel blasting is established. Based on the dynamic finite element numerical calculation method, the influence of blasting vibration on the structure of the existing high-speed railway tunnel under construction is analyzed, and the propagation and attenuation law of blasting vibration along the tunnel contour is studied. Based on the ultimate tensile stress criterion, the ultimate shear stress criterion and the Mohr criterion, and compared with the results obtained from the numerical simulation, the blasting safety criterion model of the existing high-speed railway tunnel over the tunnel is established.

In order to study the deformation and damage characteristics of the limestone specimens with high strength and brittleness under constant amplitude cyclic loading, the deformation and the acoustic emission (AE) characteristics were analysed, and the relationship between them was sought. The damage variables under different amplitude cyclic loading were defined by AE counts. The results showed that the radial deformation of the limestone specimens was more sensitive and unstable than the axial deformation. The concept of apparent residual strain was proposed to describe the specimen deformation characteristics, and it resulted that the radial apparent residual strain produced at higher stress state would recover at lower stress state. The limestone specimens showed obvious Kaiser effect and Felicity effect under cyclic loading. When the upper limit of the cyclic loading was close to the peak stress of the specimen, the AE counts generated in unloading sections were almost the same as that in the loading sections. The damage was increased as the amplitude and the stress level increased and the unloading process at higher stress level would also lead to the aggravation of damages. Specimens would absorb more energy under cyclic loading than under uniaxial loading. Reasonable driving parameters should be controlled in underground excavation practice, to ensure that the stress level of surrounding rock mass in a periodic stress state is located before peak stress and such that to limit the occurrence of rock burst to a certain extent.