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11 pages, 571 KiB  
Article
Effects of a Positive Psychology Intervention on Mental Health and Well-Being Among Mothers in Riyadh, Saudi Arabia
by Munira Abdullah AlHugail and Deemah Ateeq AlAteeq
Healthcare 2025, 13(15), 1925; https://doi.org/10.3390/healthcare13151925 - 6 Aug 2025
Abstract
Background: Concerns over women’s mental health have intensified globally, especially among mothers managing dual careers and family responsibilities. Positive Psychology Interventions (PPIs), such as gratitude journaling and well-being workshops, have demonstrated promise in enhancing mental health; however, their applicability in Arab contexts remains [...] Read more.
Background: Concerns over women’s mental health have intensified globally, especially among mothers managing dual careers and family responsibilities. Positive Psychology Interventions (PPIs), such as gratitude journaling and well-being workshops, have demonstrated promise in enhancing mental health; however, their applicability in Arab contexts remains underexplored. This study aims to investigate the effectiveness of PPIs on mothers’ well-being, gratitude, depression, anxiety, and stress in Saudi Arabia. Methods: This quasi-experimental, one-group pretest–posttest study assessed the effects of a four-week PPI on 37 Saudi working mothers (aged 21–50 years) employed at a private school in Riyadh. The intervention included guided gratitude journaling thrice weekly and two workshops on positive psychology and gratitude. Pre- and post-intervention assessments used validated Arabic versions of the Depression Anxiety Stress Scale (DASS-21), WHO-5 Well-being Index, and Gratitude Questionnaire (GQ-6). Results: Significant improvements were found post-intervention: depression, anxiety, and stress scores decreased (p < 0.001), while well-being and gratitude increased (p = 0.001). However, participants with lower household income (<50,000 SAR) showed less improvement, indicating a potential moderating effect of socioeconomic status. Conclusions: The intervention demonstrated promising short-term improvements in mental health and well-being among Saudi mothers. The findings underscore the importance of culturally appropriate PPIs and highlight the need for further research using controlled, long-term designs. Limitations include the small, non-random sample, absence of a control group, and restriction to a single geographic region. Full article
(This article belongs to the Topic Global Mental Health Trends)
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34 pages, 3002 KiB  
Article
A Refined Fuzzy MARCOS Approach with Quasi-D-Overlap Functions for Intuitive, Consistent, and Flexible Sensor Selection in IoT-Based Healthcare Systems
by Mahmut Baydaş, Safiye Turgay, Mert Kadem Ömeroğlu, Abdulkadir Aydin, Gıyasettin Baydaş, Željko Stević, Enes Emre Başar, Murat İnci and Mehmet Selçuk
Mathematics 2025, 13(15), 2530; https://doi.org/10.3390/math13152530 - 6 Aug 2025
Abstract
Sensor selection in IoT-based smart healthcare systems is a complex fuzzy decision-making problem due to the presence of numerous uncertain and interdependent evaluation criteria. Traditional fuzzy multi-criteria decision-making (MCDM) approaches often assume independence among criteria and rely on aggregation operators that impose sharp [...] Read more.
Sensor selection in IoT-based smart healthcare systems is a complex fuzzy decision-making problem due to the presence of numerous uncertain and interdependent evaluation criteria. Traditional fuzzy multi-criteria decision-making (MCDM) approaches often assume independence among criteria and rely on aggregation operators that impose sharp transitions between preference levels. These assumptions can lead to decision outcomes with insufficient differentiation, limited discriminatory capacity, and potential issues in consistency and sensitivity. To overcome these limitations, this study proposes a novel fuzzy decision-making framework by integrating Quasi-D-Overlap functions into the fuzzy MARCOS (Measurement of Alternatives and Ranking According to Compromise Solution) method. Quasi-D-Overlap functions represent a generalized extension of classical overlap operators, capable of capturing partial overlaps and interdependencies among criteria while preserving essential mathematical properties such as associativity and boundedness. This integration enables a more intuitive, flexible, and semantically rich modeling of real-world fuzzy decision problems. In the context of real-time health monitoring, a case study is conducted using a hybrid edge–cloud architecture, involving sensor tasks such as heartrate monitoring and glucose level estimation. The results demonstrate that the proposed method provides greater stability, enhanced discrimination, and improved responsiveness to weight variations compared to traditional fuzzy MCDM techniques. Furthermore, it effectively supports decision-makers in identifying optimal sensor alternatives by balancing critical factors such as accuracy, energy consumption, latency, and error tolerance. Overall, the study fills a significant methodological gap in fuzzy MCDM literature and introduces a robust fuzzy aggregation strategy that facilitates interpretable, consistent, and reliable decision making in dynamic and uncertain healthcare environments. Full article
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23 pages, 3890 KiB  
Article
Evaluating Nursing and Midwifery Students’ Self-Assessment of Clinical Skills Following a Flipped Classroom Intervention with Innovative Digital Technologies in Bulgaria
by Galya Georgieva-Tsaneva, Ivanichka Serbezova and Milka Serbezova-Velikova
Nurs. Rep. 2025, 15(8), 285; https://doi.org/10.3390/nursrep15080285 - 6 Aug 2025
Abstract
Background/Objectives: The transformation of nursing and midwifery education through digital technologies has gained momentum worldwide, with algorithm-based video instruction and virtual reality (VR) emerging as promising tools for improving clinical learning. This quasi-experimental study explores the impact of an enhanced flipped classroom [...] Read more.
Background/Objectives: The transformation of nursing and midwifery education through digital technologies has gained momentum worldwide, with algorithm-based video instruction and virtual reality (VR) emerging as promising tools for improving clinical learning. This quasi-experimental study explores the impact of an enhanced flipped classroom model on Bulgarian nursing and midwifery students’ self-perceived competence. Methods: A total of 228 participants were divided into a control group receiving traditional instruction (lectures and simulations with manikins) and an experimental group engaged in a digitally enhanced preparatory phase. The latter included pre-class video algorithms, VR, and clinical problem-solving tasks for learning and improving nursing skills. A 25-item self-report questionnaire was administered before and after the intervention to measure perceived competence in injection techniques, hygiene care, midwifery skills, and digital readiness. Results: Statistical analysis using Welch’s t-test revealed significant improvements in the experimental group in all domains (p < 0.001). Qualitative data from focus group interviews further confirmed increased student engagement, motivation, and receptiveness to digital learning tools. Conclusions: The findings highlight the pedagogical value of integrating structured video learning, VR components, and case-based learning within flipped classrooms. The study advocates for the wider adoption of blended learning models to foster clinical confidence and digital competence in healthcare education. The results of the study may be useful for curriculum developers aiming to improve clinical readiness through technology-enhanced learning. Full article
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44 pages, 7941 KiB  
Article
A Numerical Investigation of Plastic Energy Dissipation Patterns of Circular and Non-Circular Metal Thin-Walled Rings Under Quasi-Static Lateral Crushing
by Shunsong Guo, Sunting Yan, Ping Tang, Chenfeng Guan and Wei Zhang
Mathematics 2025, 13(15), 2527; https://doi.org/10.3390/math13152527 - 6 Aug 2025
Abstract
This paper presents a combined theoretical, numerical, and experimental analysis to investigate the lateral plastic crushing behavior and energy absorption of circular and non-circular thin-walled rings between two rigid plates. Theoretical solutions incorporating both linear material hardening and power-law material hardening models are [...] Read more.
This paper presents a combined theoretical, numerical, and experimental analysis to investigate the lateral plastic crushing behavior and energy absorption of circular and non-circular thin-walled rings between two rigid plates. Theoretical solutions incorporating both linear material hardening and power-law material hardening models are solved via numerical shooting methods. The theoretically predicted force-denting displacement relations agree excellently with both FEA and experimental results. The FEA simulation clearly reveals the coexistence of an upper moving plastic region and a fixed bottom plastic region. A robust automatic extraction method of the fully plastic region at the bottom from FEA is proposed. A modified criterion considering the unloading effect based on the resultant moment of cross-section is proposed to allow accurate theoretical estimation of the fully plastic region length. The detailed study implies an abrupt and almost linear drop of the fully plastic region length after the maximum value by the proposed modified criterion, while the conventional fully plastic criterion leads to significant over-estimation of the length. Evolution patterns of the upper and lower plastic regions in FEA are clearly illustrated. Furthermore, the distribution of plastic energy dissipation is compared in the bottom and upper regions through FEA and theoretical results. Purely analytical solutions are formulated for linear hardening material case by elliptical integrals. A simple algebraic function solution is derived without necessity of solving differential equations for general power-law hardening material case by adopting a constant curvature assumption. Parametric analyses indicate the significant effect of ovality and hardening on plastic region evolution and crushing force. This paper should enhance the understanding of the crushing behavior of circular and non-circular rings applicable to the structural engineering and impact of the absorption domain. Full article
(This article belongs to the Special Issue Numerical Modeling and Applications in Mechanical Engineering)
21 pages, 1343 KiB  
Article
Effectiveness of Psychoeducation via Telenursing on Reducing Caregiver Burden Among Caregivers for Patients with Schizophrenia in Saudi Arabia: A Quasi-Experimental Study
by Loujain Sharif, Manal Sadan Al-Zahrani, Fatimah Raji Alanzi, Alaa Mahsoon, Khalid Sharif, Sultan Ahmed Al-Qubali, Rebecca J. Wright and Ayman Mohamed El-Ashry
Healthcare 2025, 13(15), 1922; https://doi.org/10.3390/healthcare13151922 - 6 Aug 2025
Abstract
Background/Objectives: Family caregivers of individuals with schizophrenia often face considerable psychological and physical strain due to the complexity of caregiving. Although psychoeducation has demonstrated benefits in alleviating this burden, its provision via telenursing remains underexplored in Saudi Arabia. This study evaluated the [...] Read more.
Background/Objectives: Family caregivers of individuals with schizophrenia often face considerable psychological and physical strain due to the complexity of caregiving. Although psychoeducation has demonstrated benefits in alleviating this burden, its provision via telenursing remains underexplored in Saudi Arabia. This study evaluated the effect of a psychoeducational program delivered via telenursing on reducing caregiver burden. Methods: A quasi-experimental design was used with 60 caregivers from a tertiary mental health hospital in northern Saudi Arabia, who were divided equally into intervention and control groups. The intervention group participated in a structured four-week psychoeducational program via Zoom, while the control group received routine care. Caregiver burden was assessed using the Family Burden Interview Schedule (FBIS), a validated tool designed to measure the objective and subjective burden experienced by family members caring for individuals with mental illness. The FBIS was administered before and three months after the intervention. The statistical analysis included independent and paired t-tests and ANOVA. Results: The pre-intervention scores showed no significant differences, confirming baseline equivalence. The post-intervention scores showed a significant reduction in burden among the intervention group (p < 0.001), while no meaningful change occurred in the control group. Additionally, a lower burden was associated with higher education, sufficient income (i.e., the caregiver’s perception of being able to meet essential household expenses without financial strain), strong family support, and absence of caregiver illness. Conclusions: These findings suggest that psychoeducation through telenursing is an effective strategy for reducing caregiver burden and improving support accessibility, particularly for those in remote areas. Full article
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22 pages, 625 KiB  
Article
A Procedure to Estimate Dose and Time of Exposure to Ionizing Radiation from the γ-H2AX Assay
by Yilun Cai, Yingjuan Zhang, Hannah Mancey, Stephen Barnard and Jochen Einbeck
Information 2025, 16(8), 672; https://doi.org/10.3390/info16080672 - 6 Aug 2025
Abstract
Accurately estimating the radiation dose received by an individual is essential for evaluating potential damage caused by exposure to ionizing radiation. Most retrospective dosimetry methods require the time since exposure to be known and rely on calibration curves specific to that time point. [...] Read more.
Accurately estimating the radiation dose received by an individual is essential for evaluating potential damage caused by exposure to ionizing radiation. Most retrospective dosimetry methods require the time since exposure to be known and rely on calibration curves specific to that time point. In this work, we introduce a novel method tailored to the γ-H2AX assay, which is a protein-based biomarker for radiation exposure, that enables the estimation of both the radiation dose and the time of exposure within a plausible post-exposure interval. Specifically, we extend calibration curves available at two distinct time points by incorporating the biological decay of foci, resulting in a model that captures the joint dependence of foci count on both dose and time. We demonstrate the applicability of this approach using both real-world and simulated data. Full article
(This article belongs to the Section Biomedical Information and Health)
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10 pages, 2101 KiB  
Article
Structural and Ferromagnetic Response of B2-Type Al45Mn41.8X13.2 (X = Fe, Co, Ni) Alloys
by Esmat Dastanpour, Haireguli Aihemaiti, Shuo Huang, Valter Ström, Lajos Károly Varga and Levente Vitos
Magnetochemistry 2025, 11(8), 67; https://doi.org/10.3390/magnetochemistry11080067 - 6 Aug 2025
Abstract
To our knowledge, no magnetic B2 phase in the Al–Mn system of near-equiatomic compositions has been reported so far. Here, we investigate the structural and magnetic characteristics of Al45Mn41.8X13.2 (X = Fe, Co or Ni) alloys. We demonstrate [...] Read more.
To our knowledge, no magnetic B2 phase in the Al–Mn system of near-equiatomic compositions has been reported so far. Here, we investigate the structural and magnetic characteristics of Al45Mn41.8X13.2 (X = Fe, Co or Ni) alloys. We demonstrate that adding 13.2 atomic percent magnetic 3d metal to AlMn stabilizes a ferromagnetic B2 structure, where Al and X occupy different sublattices. We employ density functional theory calculations and experimental characterizations to underscore the role of the late 3d metals for the phase stability of the quasi-ordered ternary systems. We show that these alloys possess large local magnetic moments primarily due to Mn atoms partitioned to the Al-free sublattice. The revealed magneto-chemical effect opens alternative routes for tailoring the magnetic properties of B2 intermetallic compounds for various magnetic applications. Full article
(This article belongs to the Special Issue Advances in Functional Materials with Tunable Magnetic Properties)
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19 pages, 4202 KiB  
Article
Effect of Plate Thickness on Residual Stress Distribution of GH3039 Superalloy Subjected to Laser Shock Peening
by Yandong Ma, Maozhong Ge and Yongkang Zhang
Materials 2025, 18(15), 3682; https://doi.org/10.3390/ma18153682 - 5 Aug 2025
Abstract
To accurately assess the effect of different plate thicknesses on the residual stress field of laser shock peened GH3039 superalloy, residual stress measurements were performed on GH3039 alloy plates with thicknesses of 2 mm and 5 mm after laser shock peening (LSP) treatment. [...] Read more.
To accurately assess the effect of different plate thicknesses on the residual stress field of laser shock peened GH3039 superalloy, residual stress measurements were performed on GH3039 alloy plates with thicknesses of 2 mm and 5 mm after laser shock peening (LSP) treatment. Both quasi-static and high strain rate mechanical tests of GH3039 were conducted, and the Johnson-Cook (J-C) constitutive equation for GH3039 alloy at specific strain rates was fitted based on the experimental results. To obtain the parameter C in the J-C constitutive equation of GH3039 alloy under ultra-high strain rates, a modified method was proposed based on LSP experiment and finite element simulation results. Using the modified GH3039 alloy J-C constitutive equation, numerical simulations and comparative analyses of the residual stress field of GH3039 alloy plates of different thicknesses under LSP were carried out using ABAQUS software. The simulated residual stress fields of laser-shocked GH3039 alloy plates of different thicknesses were in good agreement with the experimental measurements, indicating that the modified GH3039 alloy J-C constitutive equation can accurately predict the mechanical behavior of GH3039 alloy under ultra-high strain rates. Based on the modified GH3039 alloy J-C constitutive equation, the effect of different plate thicknesses on the residual stress distribution of laser-shocked GH3039 alloy was studied, along with the underlying mechanisms. The unique distribution characteristics of residual stresses in laser-shocked GH3039 plates with varying thicknesses are primarily attributed to differences in plate bending stiffness and the detrimental coupling effects of reflected tensile waves. Full article
(This article belongs to the Section Metals and Alloys)
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19 pages, 618 KiB  
Article
Effect of a Nutritional Education Intervention on Sports Nutrition Knowledge, Dietary Intake, and Body Composition in Female Athletes: A Pilot Study
by Macarena Veloso-Pulgar and Andreu Farran-Codina
Nutrients 2025, 17(15), 2560; https://doi.org/10.3390/nu17152560 - 5 Aug 2025
Abstract
Background/Objectives: Studies have reported that female athletes often exhibit low levels of nutritional knowledge and inadequate dietary intake to meet their nutritional needs. The aim of this study was to evaluate the effect of a nutritional education intervention on nutrition knowledge, dietary intake, [...] Read more.
Background/Objectives: Studies have reported that female athletes often exhibit low levels of nutritional knowledge and inadequate dietary intake to meet their nutritional needs. The aim of this study was to evaluate the effect of a nutritional education intervention on nutrition knowledge, dietary intake, and body composition in female handball players (n = 45; age, 17.6 ± 2.1 years). Methods: A quasi-experimental intervention design was implemented, consisting of a 3-week educational program delivered through six in-person sessions led by a registered dietitian. Nutrition knowledge, dietary intake, adherence to the Mediterranean diet, and anthropometric and body composition measurements were assessed. Results: Nutrition knowledge levels were significantly higher both immediately post-intervention and three months later compared to baseline (p < 0.05, ES > 0.8). A total of 36 participants completed a 3-day dietary record at baseline and at follow-up. Initial assessments revealed insufficient energy (31 kcal/kg/day) and carbohydrate intake (3.0 g/kg/day) and a high intake of total fats (1.4 g/kg/day). During follow-up, a significant decrease in the consumption of foods rich in sugar was observed (p = 0.0272). A total of 82.2% of the players needed to improve their adherence to the Mediterranean diet. No significant changes were found in Mediterranean diet adherence or body composition following the intervention. Conclusions: The nutritional education intervention significantly improved athletes’ nutritional knowledge and significantly decreased their consumption of sugary foods; however, further studies are needed to evaluate its impact on dietary intake and body composition, considering the study’s limitations. Full article
(This article belongs to the Special Issue Food Habits, Nutritional Knowledge, and Nutrition Education)
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28 pages, 10200 KiB  
Article
Real-Time Temperature Estimation of the Machine Drive SiC Modules Consisting of Parallel Chips per Switch for Reliability Modelling and Lifetime Prediction
by Tamer Kamel, Olamide Olagunju and Temitope Johnson
Machines 2025, 13(8), 689; https://doi.org/10.3390/machines13080689 - 5 Aug 2025
Abstract
This paper presents a new methodical procedure to monitor in real time the junction temperature of SiC Power MOSFET modules of parallel-connected chips utilized in machine drive systems to develop their reliability modelling and predict their lifetime. The paper implements the on-line measurements [...] Read more.
This paper presents a new methodical procedure to monitor in real time the junction temperature of SiC Power MOSFET modules of parallel-connected chips utilized in machine drive systems to develop their reliability modelling and predict their lifetime. The paper implements the on-line measurements of temperature-sensitive electrical parameters (TSEP) approach, particularly the quasi-threshold voltage and the on-state drain to source voltage, to estimate the junction temperature in real time. The proposed procedure firstly applied computational fluid dynamics analysis on the module under study to determine the chip which undergoes the maximum junction temperature during typical operation of the module. Then, a calibration phase, using double-pulse tests on the selected chip, is used to generate look-up tables to relate the TSEPs under study to the junction temperature. Next, the real-time estimation of junction temperature was accomplished during the on-line operation of the three-phase inverter, taking into account the induced distortion/noises due to operation of the parallel-connected chips in the module. After that, a comparison between the two TSEPs under study was provided to demonstrate their advantages/drawbacks. Finally, reliability modelling was developed to predict the lifetime of the studied module based on the estimated junction temperature under a predetermined mission profile. Full article
(This article belongs to the Special Issue Power Converters: Topology, Control, Reliability, and Applications)
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25 pages, 4865 KiB  
Article
Mathematical Modeling, Bifurcation Theory, and Chaos in a Dusty Plasma System with Generalized (r, q) Distributions
by Beenish, Maria Samreen and Fehaid Salem Alshammari
Axioms 2025, 14(8), 610; https://doi.org/10.3390/axioms14080610 - 5 Aug 2025
Abstract
This study investigates the dynamics of dust acoustic periodic waves in a three-component, unmagnetized dusty plasma system using generalized (r,q) distributions. First, boundary conditions are applied to reduce the model to a second-order nonlinear ordinary differential equation. [...] Read more.
This study investigates the dynamics of dust acoustic periodic waves in a three-component, unmagnetized dusty plasma system using generalized (r,q) distributions. First, boundary conditions are applied to reduce the model to a second-order nonlinear ordinary differential equation. The Galilean transformation is subsequently applied to reformulate the second-order ordinary differential equation into an unperturbed dynamical system. Next, phase portraits of the system are examined under all possible conditions of the discriminant of the associated cubic polynomial, identifying regions of stability and instability. The Runge–Kutta method is employed to construct the phase portraits of the system. The Hamiltonian function of the unperturbed system is subsequently derived and used to analyze energy levels and verify the phase portraits. Under the influence of an external periodic perturbation, the quasi-periodic and chaotic dynamics of dust ion acoustic waves are explored. Chaos detection tools confirm the presence of quasi-periodic and chaotic patterns using Basin of attraction, Lyapunov exponents, Fractal Dimension, Bifurcation diagram, Poincaré map, Time analysis, Multi-stability analysis, Chaotic attractor, Return map, Power spectrum, and 3D and 2D phase portraits. In addition, the model’s response to different initial conditions was examined through sensitivity analysis. Full article
(This article belongs to the Special Issue Trends in Dynamical Systems and Applied Mathematics)
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18 pages, 2763 KiB  
Article
Enhancing Students’ Interest in Physics Concepts with a Low-Cost STEM Tool Focused on Motivation in Rural Areas of Developing Countries
by René Flores-Godínez, Antonio Alarcón-Paredes, Iris Paola Guzmán-Guzmán, Yanik Ixchel Maldonado-Astudillo and Gustavo Adolfo Alonso-Silverio
Educ. Sci. 2025, 15(8), 994; https://doi.org/10.3390/educsci15080994 (registering DOI) - 5 Aug 2025
Abstract
Physics concepts are considered an essential component of STEM (science, technology, engineering, and mathematics) education and fundamental for economic and technological development in the world. However, there can be student academic underperformance, such as the school environment, learning media and infrastructure, student interest [...] Read more.
Physics concepts are considered an essential component of STEM (science, technology, engineering, and mathematics) education and fundamental for economic and technological development in the world. However, there can be student academic underperformance, such as the school environment, learning media and infrastructure, student interest and emotions, as well as social and economic development factors in communities. These problems are even more acute in rural areas of developing countries, where poverty is high and teachers often lack the necessary technological skills. The aim of this study was to evaluate the impact of a low-cost STEM tool focused on motivation in learning, in terms of five variables of interest in physics in rural areas, as well as the durability of the tools used to learn 12 physics concepts. A quasi-experimental study was conducted with the participation of 78 high school students, with an average age of 15.82 years, in a rural area of Guerrero, Mexico. The results showed that using the STEM tool significantly increased students’ interest in learning methodology, active participation, and attitude towards physics, facilitating the teacher’s work. In addition, the 3D construction kit used in the experimentation, besides being low-cost, proved to be affordable and durable, making it ideal for use in rural areas. Full article
(This article belongs to the Special Issue Interdisciplinary Approaches to STEM Education)
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32 pages, 12538 KiB  
Article
Study on Vibration Characteristics and Harmonic Suppression of an Integrated Electric Drive System Considering the Electromechanical Coupling Effect
by Yue Cui, Hong Lu, Jinli Xu, Yongquan Zhang and Lin Zou
Actuators 2025, 14(8), 386; https://doi.org/10.3390/act14080386 - 4 Aug 2025
Abstract
The study of vibration characteristics and suppression methods in integrated electric drive systems of electric vehicles is of critical importance. To investigate these characteristics, both current harmonics within the motor and nonlinear factors within the drivetrain were considered. A 17-degree-of-freedom nonlinear torsional–planar dynamic [...] Read more.
The study of vibration characteristics and suppression methods in integrated electric drive systems of electric vehicles is of critical importance. To investigate these characteristics, both current harmonics within the motor and nonlinear factors within the drivetrain were considered. A 17-degree-of-freedom nonlinear torsional–planar dynamic model was developed, with electromagnetic torque and output speed as coupling terms. The model’s accuracy was experimentally validated, and the system’s dynamic responses were analyzed under different working conditions. To mitigate vibrations caused by torque ripple, a coordinated control strategy was proposed, combining a quasi-proportional multi-resonant (QPMR) controller and a full-frequency harmonic controller (FFHC). The results demonstrate that the proposed strategy effectively suppresses multi-order current harmonics in the driving motor, reduces torque ripple by 45.1%, and enhances transmission stability. In addition, the proposed electromechanical coupling model provides valuable guidance for the analysis of integrated electric drive systems. Full article
(This article belongs to the Section Actuators for Surface Vehicles)
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12 pages, 223 KiB  
Article
Improving Pain Management in Critically Ill Surgical Patients: The Impact of Clinical Supervision
by Telma Coelho, Diana Rodrigues and Cristina Barroso Pinto
Surgeries 2025, 6(3), 67; https://doi.org/10.3390/surgeries6030067 - 4 Aug 2025
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Abstract
Background: Pain is a problem faced by critically ill surgical patients and has a major impact on their outcomes. Pain assessment is therefore essential for effective pain management, with a combination of pharmacological and non-pharmacological treatment. Clinical supervision, supported by models such as [...] Read more.
Background: Pain is a problem faced by critically ill surgical patients and has a major impact on their outcomes. Pain assessment is therefore essential for effective pain management, with a combination of pharmacological and non-pharmacological treatment. Clinical supervision, supported by models such as SafeCare, can improve professional development, safety and the quality of care in intensive care units. Objectives: This study aimed to: (1) assess current pain assessment practices in a polyvalent Intensive Care Unit (ICU) in the Porto district; (2) identify nurses’ training needs regarding the Clinical Supervision-Sensitive Indicator—Pain; and (3) evaluate the impact of clinical supervision sessions on pain assessment practices. Methods: A quantitative, quasi-experimental, cross-sectional study with a pre- and post-intervention design was conducted. Based on the SafeCare model, it included a situational diagnosis, 6 clinical supervision sessions (February 2023), and outcome evaluation via nursing record audits (November 2022 and May 2023) in 31 total critical ill patients. Pain was assessed using standardised tools, in line with institutional protocols. Data was analysed using Software Statistical Package for the Social Sciences v25.0. Results: Pain was highly prevalent in the first 24 h, decreasing during hospitalisation. Generalised acute abdominal pain predominated, with mild to moderate intensity, and was exacerbated by wound care and mobilisation/positioning. Pain management combined pharmacological and non-pharmacological treatment. There was an improvement in all the parameters of the pain indicator post-intervention. Conclusions: Despite routine assessments, gaps remained in reassessing pain post-analgesia and during invasive procedures. Targeted clinical supervision and ongoing training proved effective in improving compliance with protocols and supporting safer, more consistent pain management. Full article
20 pages, 3145 KiB  
Article
Determination of Dynamic Elastic Properties of 3D-Printed Nylon 12CF Using Impulse Excitation of Vibration
by Pedro F. Garcia, Armando Ramalho, Joel C. Vasco, Rui B. Ruben and Carlos Capela
Polymers 2025, 17(15), 2135; https://doi.org/10.3390/polym17152135 - 4 Aug 2025
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Abstract
Material Extrusion (MEX) process is increasingly used to fabricate components for structural applications, driven by the availability of advanced materials and greater industrial adoption. In these contexts, understanding the mechanical performance of printed parts is crucial. However, conventional methods for assessing anisotropic elastic [...] Read more.
Material Extrusion (MEX) process is increasingly used to fabricate components for structural applications, driven by the availability of advanced materials and greater industrial adoption. In these contexts, understanding the mechanical performance of printed parts is crucial. However, conventional methods for assessing anisotropic elastic behavior often rely on expensive equipment and time-consuming procedures. The aim of this study is to evaluate the applicability of the impulse excitation of vibration (IEV) in characterizing the dynamic mechanical properties of a 3D-printed composite material. Tensile tests were also performed to compare quasi-static properties with the dynamic ones obtained through IEV. The tested material, Nylon 12CF, contains 35% short carbon fibers by weight and is commercially available from Stratasys. It is used in the fused deposition modeling (FDM) process, a Material Extrusion technology, and exhibits anisotropic mechanical properties. This is further reinforced by the filament deposition process, which affects the mechanical response of printed parts. Young’s modulus obtained in the direction perpendicular to the deposition plane (E33), obtained via IEV, was 14.77% higher than the value in the technical datasheet. Comparing methods, the Young’s modulus obtained in the deposition plane, in an inclined direction of 45 degrees in relation to the deposition direction (E45), showed a 22.95% difference between IEV and tensile tests, while Poisson’s ratio in the deposition plane (v12) differed by 6.78%. This data is critical for designing parts subject to demanding service conditions, and the results obtained (orthotropic elastic properties) can be used in finite element simulation software. Ultimately, this work reinforces the potential of the IEV method as an accessible and consistent alternative for characterizing the anisotropic properties of components produced through additive manufacturing (AM). Full article
(This article belongs to the Special Issue Mechanical Characterization of Polymer Composites)
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