Journal of Mechatronics and Artificial Intelligence in Engineering
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Assessment of the impact of TE33A diesel locomotive wheelsets on the railway track in a straight section of the track
Get PDFThe purpose of the article is an experimental study of the impact of the wheelsets of a mainline diesel locomotive on the railway track on straight sections of the track. The measurements were performed on a vibration measuring device consisting of MV25 DV type sensors and an oscillation converter for a digital signal. It is proved that the indicators of dynamic characteristics comply with regulatory requirements. As a result of the conducted research, digital data was collected from the ADC and general monitoring was carried out. Measurement and signal processing are carried out using special software of a personal computer such as a “Notebook”. Vertical static load of a wheelset of a railway rolling stock unit on rails: the load of a railway rolling stock unit on rails attributed to one wheelset, taking into account the actual location of the center of gravity of the superstructure
Tensor analysis of tornadoes: a new analytical and numerical model
Get PDFThis research proposes a new mathematical formulation of tornadoes based on the theory of tensor analysis and simulation in a non-inertial dynamics framework, both in two and three dimensions. This model may show the spherical upward movement of air in a tornado without taking into account vertical convection. A tornado requires several elements, including geocentric latitude, the Coriolis effect, increased airspeed in the upper atmosphere, and increased air pressure. Computing the three-dimensional location of the tornado or hurricane, as well as the mathematical models of airflow motion and the Earth's rotation in three-dimensional (3D) space, can determine a tornado's airflow characteristics. To show tornado patterns, we employed computer software that computed motion dynamics and did numerical computations. The results of 2-D modeling and simulation indicated that the greater the initial tornado angular speed, the larger the tornado area. Three-dimensional modeling and simulation also show that tornadoes are more powerful at higher geocentric latitude angles. The novelty of this study is that this model can be used to explain tornado patterns. In our research, we combine tensor analysis, computational modeling, as well as 2D and 3D simulations for simulating tornadoes for the first time. The scientific application of this finding is that researchers at the Meteorology, Climatology, and Geophysics Agency will be able to analyze a tornado and geophysical phenomena more readily with simulations and models
Photogrammetry protocol in babies with congenital torticollis: part 1 – inter-arch intraoral assessment
Get PDFTorticollis is defined as an imbalance of the sternocleidomastoid muscle (SCM), with less extension of the neck, resulting in a preference to turn the head more from one side to the other. The characteristics frequently found are: ear contralateral to the torticollis displaced forward, facial asymmetry, and contralateral occipital flattening, as well as a smaller ipsilateral eye, causing misalignment of the eyes. This condition can also cause mandibular inclination (MI), in the frontal plane, with a difference in opening between the maxilla and mandible from one side or the other. The diagnosis and treatment of torticollis are routinely carried out by the physiotherapist and the diagnosis of this mandibular inclination is traditionally through visual examination. This assessment of mandibular inclination, carried out by the dentist, in an objective manner, can contribute to the diagnosis and also to the monitoring of proposed treatments that should reduce mandibular asymmetries. The objective of this study was to create a protocol for objective measurement of the distance between the maxilla and mandible, on the right and left sides, using photogrammetry, to detect whether mandibular inclination can be observed by the shorter inter-arch distance on the side corresponding to the torticollis. Case reports of two babies (1 baby aged 9 months and another aged 1 year and 1 month), diagnosed with congenital torticollis. Photogrammetry was carried out: the babies were positioned on a dental stretcher and photographed in maximum opening, intermediate, and closing positions. Using the photos and the IMAGE J program, measurements between the maxilla and mandible were taken (see photogrammetry description). Results: The measurement protocol used in both babies confirmed the greater mandibular inclination by approaching the hemi-arch corresponding to the side of the torticollis, compared to the opposite side. Objective measurement of mandibular inclination can be part of the timely diagnosis for congenital torticollis. Studies with an adequate sample size and methodology are necessary to confirm this diagnostic tool
Numerical modelling of the warping behaviour at the first layer-build plate interface in 3D-printed models produced via the fused deposition modelling process
Get PDFThe material structure of 3D-models printed via the fused deposition modelling (FDM) technique is mainly affected in the z-direction of the 3D-print as a result of the layer-by-layer approach which tend to exhibit a deformation behavior corresponding to a type of transversely orthotropic material. Moreover, uncontrolled parameters such as printing temperature and printing speed have been reported to adversely affect 3D-print quality leading to undesired effects such as distortion and warpage. The additive manufacturing process is a relatively new field in advanced manufacturing where further research and innovation are required to overcome the limited strength and structural performance observed in presently 3D-printed components. In line with the above, this study proposes the numerical investigation of the warping behavior in PLA (Polylactic acid) - based 3D printed models by considering the finite element method (FEM) software of LS-DYNA. The warping investigation was specifically centered on the cooling cycle prevailing between the layer-by-layer structures. The findings of this study showed that warpage would most likely occur in the thermal process model corresponding to abrupt change in temperature due to a buildup of strain between the bottom most layers of the 3D model and the build plate. The findings of this study, which shed light on the warping behaviour in 3D-models, has direct implications on the final quality of 3D-printed components
Welcoming pregnant women as a strategy for adherence to dental prenatal care and health promotion in early childhood
Get PDFThis research deals with implementing Dental Prenatal Care as a public policy in the Brazilian Unified Health System (SUS) to care for pregnant women and their future babies. The legal framework that assures pregnant women's rights of priority in accessing services is usually not enough to guarantee the health promotion coverage goals for this population group, who frequently have low adherence to dental care. Brazilian Unified Healthcare System (SUS) recommends monitoring pregnant women through eight mensal consultations during healthy pregnancy. Oral health is usually not monitored to the same extent, and many pregnant women still go through pregnancy without any dental consultation. This study was proposed to improve dental prenatal care and program adherence by mothers and children in the Basic Healthcare Unit Amaro José de Souza, in the municipality of Barueri, through the increased participation of the dental surgeon in the pregnant women welcoming team. A cross-sectional cohort study was designed to identify and meet the demands of low-risk pregnant women. For six months, all the women attending prenatal care at BHU Amaro José de Souza in Barueri were invited to participate and receive personal guidance from the multi-professional team. Information on dental health was investigated through questions targeting previous knowledge about the recommended moments for the first dental appointment of a child, the importance of exclusive nasal respiration, the identification of craniofacial asymmetries at birth, and general baby care. Attitudes and self-care were also investigated, including prenatal program adherence. Answers were collected in a Google Form platform and analyzed to characterize the group's literacy about prenatal care and breastfeeding and identify information needs about dental health care during pregnancy. At the same time, a welcoming expanded listening, educational, and preventive health action was developed: conversation and sharing experience groups were promoted monthly for pregnant women, breastfeeding mothers, and their families. 90 pregnant women out of the 104 attending the BHU in the six months of the research were invited, and 83 agreed to participate. All the participants declared at least one previous appointment with the healthcare team, 92.8 % of them, with a gynecologist. The nursing team was involved in 53.0 % of the appointments, but only 6.0 % were reported to have been conducted exclusively by a nurse. A dental surgeon appointment was mentioned by 30.1 % of the research participants. The dental health literacy investigation revealed that 57.8 % believed they should only take their babies to a dental appointment after teething, and 27.7 % were aware of the child's craniofacial asymmetries at birth. Only 28.9 % had previous knowledge about the importance of exclusive nasal respiration. Despite only 34.9 % having their first pregnancy, 78.3 % declared they would appreciate receiving information about pregnancy. After the guidance, 72.0 % of the pregnant women had undergone dental prenatal care. Workshops for pregnant women and breastfeeding mothers provided a convenient welcoming space, to listen and provide guidance to pregnant women and their families, in addition to demystifying the fear of dental care during pregnancy and breastfeeding. The intervention to guide pregnant women to perceive the BHU as an educational and health promotion space, not just a curative intervention, effectively increased adherence to dental prenatal care. The contact with the Specialist in Functional Jaw Orthopedics in this first phase of life facilitated dental health education and access to more complex cases. The prenatal program adherence, the pregnant woman’s self-care, and the care of the baby were favored by the welcoming, expanded listening, and personalized service
Editor’s Letter. Special issue on bioengineering innovations at Bioengineering Laboratory of the Federal University of Minas Gerais
Get PDFMotor fault diagnosis based on composite multi-scale weighted reverse slope entropy and neighborhood preserving embedding
Get PDFThe motors are critical components of the electromechanical transmission in vehicles, and its operating status directly affects the maneuverability of vehicles. To quickly and accurately identify the operating status of motors, this paper proposes a new entropy - Composite Multi-scale Weighted Reverse Slope Entropy (CMWRSlE) for motor fault diagnosis, which is a more interpretable entropy due to its deep exploration of signals. Firstly, the composite multi-scale weighted reverse slope entropy values are extracted from the vibration signals of the motor in different states; Secondly, the extracted features are dimensionally reduced by the manifold learning algorithm – Neighbourhood Preserving Embedding (NPE) and classified by the hierarchical prototype-based approach (HPA) to achieve the fault diagnosis of the motor. Finally, the method proposed in this paper is validated through two sets of experimental data: motor rotor faults and motor bearing faults. The results show that the accuracy of the proposed method in motor fault diagnosis reaches 100 %, which indicates the effectiveness of the proposed method
Adaptive robust control of electromagnetic actuators with friction nonlinearity and uncertainty compensation
Get PDFFriction nonlinearity and uncertainty are the main factors affecting the highly performance control of electromagnetic actuators. In this paper, a nonlinear adaptive robust control strategy is proposed of electromagnetic actuators with friction nonlinearity and uncertainty compensation. First, the dynamical model of the electromagnetic actuator is established considering nonlinearity and uncertainty. Then, an adaptive robust controller is designed based on the continuously differentiable friction model to ensure that the control input is continuously and bounded. In the design of the controller, the unfavorable effects of unknown parameters in the electromagnetic actuator are eliminated by constructing a parameter adaptive law. Meanwhile, in order to improve the tracking accuracy of the electromagnetic actuator, a nonlinear robust control law is designed to ensure the robustness of the controller. The stability analysis by Lyapunov function shows that the asymptotic tracking effect can be obtained when only parameter uncertainty exists in the closed-loop system of the electromagnetic actuator, and the consistent bounded stability can be ensured when the system also exists uncertain nonlinearity. Extensive comparative results verify the effectiveness of the proposed control method
A CNN-BiLSTM algorithm for Weibo emotion classification with attention mechanism
Get PDFWeibo short text information contains a large amount of network language, emoticons, etc., and due to the long-time span of the content, the emotions of the posts posted by people often change due to time or the occurrence of certain special events. Therefore, traditional sentiment analysis methods are not suitable for this task. This article proposes a CNNs-Bi LSTM sentiment analysis method that integrates attention mechanism. It combines convolutional neural networks and bidirectional short-term memory networks to obtain keyword information in text through attention mechanism, efficiently and accurately realizing data temporal and semantic information mining. Through experimental verification using Weibo public opinion data, the results show that this method achieves higher accuracy compared to other benchmark models and can fully utilize multidimensional matrices to capture rich text features, with certain advantages
Case report – distoclusion treated with Bimler A períod of 12 months
Get PDFThe Bimler type A utilizes forces derived from muscles, particularly the tongue, concomitantly, it acts as a systemic, dynamic and functional treatment, Bimler appliances transmit neural excitation throughout the system. The objective of this study was to present a clinical case and demonstrate the efficacy of the functional orthopedic appliance, specifically the Bimler A elastic modeler, in the treatment of a patient diagnosed with distoclusion (prognathism of the maxilla and retrognathism of the mandible) according to Bimler and McNamara cephalometry. The case involved a 9-year and 11-month-old male patient with atypical swallowing, respiratory issues, and allergic conditions such as asthma. Clinical examination and complementary tests revealed a large overjet, a narrow maxilla and mandible, an open bite, and distoclusion (retrognathism). The proposed intervention included the installation of the Bimler Elastic Modeler (BEM), type A. The treatment duration was 12 months, with ongoing monitoring every 2 or 3 months. The comprehensive approach, combining BEM type A, chewing exercises, and occlusal adjustments, resulted in orthopedic changes improved mandibular, tongue, lip, and head posture, as well as enhanced chewing balance. Importantly, the appliance effectively repositioned the mandible into a more balanced, normoccluded position without the need for elastic or constant forces. Beyond the orthodontic changes, the active engagement of facial expression muscles during these activities contributed to an overall improvement in facial harmony, achieving lip seal and notable enhancements in breathing. These positive changes extended to the patient’s daily activities and sports performance. The observed outcomes not only increased the child’s active participation in the treatment but also positively impacted self-esteem, driven by the aesthetic, functional, and psychological improvements experienced