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Computer-aided design, manufacturing and engineering technologies (CAD/CAM/CAE) are a mainstay in today's industry and therefore they should be an important part in the current training plan of the graduate engineers. However, their implementation in the university environment presents certain barriers that make it difficult. In this work, we study the feasibility of the teaching proposal of the management of this type of tools through a Project-Based Learning method in a distance learning environment. The methodology has been implemented transversally in two Master's degree subjects related to advanced design and manufacturing and has been carried out thanks to the operation of the product lifecycle management platform software by virtual machines. The practice has given very good pedagogical results in the work of skills related to the field of industrial design and manufacturing. The virtual system has demonstrated high efficiency and students have shown a satisfactory evolution in their professional training.

Background: The prevention and treatment of bone loss and osteoporotic fractures is a public health challenge. Combined with normobaric hypoxia, whole-body vibration has a high clinic potential in bone health and body composition. The effect of this therapy may be mediated by its action on bone marrow mesenchymal stem cells (MSCs). Objectives: Evaluate the effects of cyclic low-vibration stimuli and/or hypoxia on bone marrow-derived human MSC differentiation. Methods: MSCs were exposed four days per week, two hours/day, to hypoxia (3% O2) and/or vibration before they were induced to differentiate or during differentiation into osteoblasts or adipocytes. Gene and protein expression of osteoblastic, adipogenic, and cytoskeletal markers were studied, as well as extracellular matrix mineralization and lipid accumulation. Results: early osteoblastic markers increased in undifferentiated MSCs, pretreated in hypoxia and vibration. This pretreatment also increased mRNA levels of osteoblastic genes and beta-catenin protein in the early stages of differentiation into osteoblasts without increasing mineralization. When MSCs were exposed to vibration under hypoxia or normoxia during osteoblastic differentiation, mineralization increased with respect to cultures without vibrational stimuli. In MSCs differentiated into adipocytes, both in those pretreated as well as exposed to different conditions during differentiation, lipid formation decreased. Changes in adipogenic gene expression and increased beta-catenin protein were observed in cultures treated during differentiation. Conclusions: Exposure to cyclic hypoxia in combination with low-intensity vibratory stimuli had positive effects on osteoblastic differentiation and negative ones on adipogenesis of bone marrow-derived MSCs. These results suggest that in elderly or frail people with difficulty performing physical activity, exposure to normobaric cyclic hypoxia and low-density vibratory stimuli could improve bone metabolism and health. [ABSTRACT FROM AUTHOR]

Background: For engineering students, a lack of motivation and continuous study are common issues that lie in low academic performance. Active teaching with audio‐visual systems, on the one hand, and self‐regulated learning methodologies, on the other, have shown to have a high potential in these aspects. Purpose: Assessing a proposal based on a self‐assessment and integrating it into a traditional teaching process to improve student engagement and performance. Design/Method: When once explanation of a thematic block was complete, we set a series of exercises encompassing key concepts for students to solve at home within a limited time. Students then had to upload their solutions to an e‐Learning platform and subsequently received dynamic videos, created using a lightboard studio, showing solutions to the exercises to assess their level of learning through self‐evaluation. Results: The activity was highly valued by the students. They were more motivated in their studies than the control group, which is reflected in increased participation in the course and in the number of students who sat for the exams. However, according to the metrics of the videos and their responses to the questionnaires, students did not fully utilise the available resources. This is likely due to the extrinsic motivation facilitated or failure to treat the self‐assessments as exam simulations. This resulted in academic performance that is very similar to that of the control group. Conclusions: The results obtained demonstrate the usefulness of the teaching proposal for the purpose of this work, although it requires some improvements. [ABSTRACT FROM AUTHOR]

Trunk shakers perform a forced vibration that should be set according to tree species and architecture to efficiently detach fruits. However, manufacturing companies produce designs that are poorly customisable according to different trees. This work presents a prototype that is configurable in amplitude and frequency of vibration, which has been developed to generate the different vibration patterns required by various fruit trees. To study the feasibility of the developed technology, we built a test bench with a post, to which we fixed olive, almond and orange tree branches, and tested different configurations of the machine (frequencies from 12.25 to 20.75 Hz and eccentricities from 58 to 86 mm). Acceleration values were recorded at different points: the trunk shaker, the post in the grip, the top of the post, and in each branch. We recorded a large loss of acceleration transmissibility between the shaker and the post (20%–60%) due to existing frictions that dissipate energy through heat loss. There is a non-linear increase between vibration frequency and the resultant acceleration value recorded, as well as with increasing eccentricity. The shaker was able to provide a different vibration pattern in each configuration, affecting the transmission of vibration in each of the branches studied, for which mean acceleration transmissibility ranged between 82% (almond), 104% (olive) and 136% (orange). [ABSTRACT FROM AUTHOR]

Vibration-based energy harvesting represents a clean power technology that can be of interest for application in civil engineering structures. This study focuses on energy harvesting using cantilever piezoelectric devices excited by operational and ambient bridge vibration. The optimal design and analysis of energy harvesters is usually performed using the mean and standard deviation of a response quantity of interest (i.e. voltage) under broadband Gaussian white noise excitation. In this paper, a novel holistic approach to the problem is proposed through the statistics of the voltage of piezoelectric energy harvesters under real measured bridge vibration base excitation. A new semi-analytic expression of the expected power is developed. The solution is based on the closed-form of the frequency response function between the harvester output voltage and the base excitation, and the experimentally measured spectral density of the latter. A study on the influence of the electromechanical coupling of the problem equations is first conducted. Then, a sensitivity analysis of the piezoelectric energy harvester parameters is performed. The critical analysis is developed through a case study of the measured long-term vibrations of a bowstring-arch highway bridge. Both operational and ambient vibration records are considered in the feasibility study. The results show the potential of the semi-analytic expression to evaluate the harvested power of piezoelectric harvesters under operational structural vibration. This is a promising approach to confidently develop future analyses on the power requirements of wireless sensor networks for SHM. [ABSTRACT FROM AUTHOR]