Search Results (660)

A robust speed controller integrating the slime mold algorithm (SMA) with sliding mode theory (SMT) is proposed for induction motor (IM) drives operating under field-oriented control (FOC). Unlike conventional controllers with fixed gain parameters, the proposed exponential reaching law sliding mode controller (ERLSMC) defines the sliding mode dynamic trajectory control gain, exponential reaching gain, and constant-speed reaching gain as the search space for the SMA. An adaptive fitness function based on the speed error and its rate of change is constructed to continuously evaluate and update these gain parameters, thereby determining the optimal controller gains according to the current operating state. Consequently, larger gain values are assigned when the system state is far from the sliding mode dynamic trajectory to accelerate the reaching process, whereas smaller gain values are adopted near the sliding mode dynamic trajectory to suppress chattering and reduce overshoot. Matlab/Simulink (2024b version) simulations are conducted to evaluate the proposed controller in an IM drive system and compare its performance with constant-speed reaching law sliding mode control, exponential reaching law sliding mode control, and zebra optimization algorithm (ZOA)-based ERLSMC methods. The simulation results demonstrate that the proposed controller achieves superior performance in both speed command tracking and load regulation response. Full article

Background: Multiple sclerosis (MS) is a chronic disease of the central nervous system, characterised by high variability in both its progression and symptoms. The disease leads to progressive disability, which manifests itself as slow walking, low muscle mass and impaired manual dexterity, causing difficulties in performing everyday activities and reducing a patient’s social activity and quality of life. The aim of this study is to assess the relationships between muscle mass, physical activity and the food frequency of protein-rich products and the functional fitness of patients with MS. Methods: The study comprised 106 patients with MS (83 women and 23 men) aged 18–65 years. Measurements of their weight and body composition, motor function of the lower limbs using the Timed 25-Foot Walking Test (T25FW), and motor function of the upper limbs using the 9-Hole Peg Test (9-HPT) and the Handgrip Strength (HGS) test were performed. Daily moderate-to-vigorous physical activity (MVPA) and the consumption frequency of protein-rich products were also assessed. Results: Low muscle mass was associated with worse performance in the HGS test (non-dominant hand p = 0.001, dominant hand p = 0.001), while no significant associations were observed for manual dexterity or T25FW performance.. The second tercile of MVPA was significantly associated with reduced HGS in the dominant (p = 0.037) and non-dominant hands (p = 0.015). Conversely, the third tercile of the MVPA compared to the lower tertile was associated with better HGS of the non-dominant hand (p = 0.022) and faster completion of the 9-HPT with the non-dominant (p = 0.010) and dominant hands (p = 0.029). Furthermore, frequent consumption of protein-rich products was correlated with faster completion of the T25FW test (p = 0.033). Conclusions: Regular physical activity is associated with better functional fitness, while more frequent consumption of protein-rich foods may be associated with higher muscle mass of major muscle groups, which is important for effective locomotion. This study has a cross-sectional and exploratory design; therefore, the findings reflect associations only and do not allow casual inferences. Full article

This study addresses pressure regulation in an induction-motor-driven centrifugal fan and introduces two complementary novelties: a Softsign-PI controller that shapes the tracking error via a Softsign nonlinearity before PI regulation and a hybrid starfish optimization with a differential evolution (hSFOA-DE) scheme for automatically tuning the controller parameters. The approach is evaluated on an experimentally validated nonlinear fan–motor model and benchmarked against modern metaheuristics—starfish optimization algorithm (SFOA), animated oat optimization (AOO), electric eel foraging optimization (EEFO), differential evolution (DE), particle swarm optimization (PSO)—as well as classical tunings—Murrill-based 2-DOF PID, Tyreus–Luyben PID and Ziegler–Nichols PI. Statistical summaries and boxplots indicate superior central tendency with reduced run-to-run variability; fitness–evolution curves show faster convergence; and time-domain performance metrics confirm improved transient and steady-state behaviour. Objective function comparisons further show the lowest values of both the Zwe-Lee Gaing (ZLG) and integral of absolute error (IAE), supporting advantages in robustness and tracking accuracy of the proposed approach. These gains reduce overshoot and cumulative error, which can lessen throttling losses and actuator duty in fan/pump service, suggesting potential energy and maintenance benefits. Full article

At the Second Water Intake Pump Station of the Chenhang Reservoir in Shanghai, suboptimal pump scheduling resulted in electricity consumption cost attributable to pump-motor equipment accounting for an exceptionally large proportion of the total power expenditure. In response to the economical operation issues, a mathematical model of power consumption cost for the pump station was established by introducing time-of-use electricity pricing and constraint suppression terms. Taking the minimum cost as the research objective, the differential evolution (DE) algorithm was employed to establish a fitness function for electricity cost, aiming to find the most economical and reliable scheduling strategy. However, owing to its low computational speed and high complexity, machine learning was introduced to establish neural network surrogate models of the DE algorithm. By comparing three surrogate models, the Multilayer Perceptron (MLP) neural network model was adopted as the most appropriate surrogate model. It was optimized for robustness improvement and verified on site. The results demonstrate that implementing the surrogate model achieves over 25% savings in electricity cost per thousand cubic meters of water, while slashing the solution time by 88.53% compared to the standard DE algorithm. Furthermore, the overall power consumption is reduced by 2.20% under a cost-priority strategy and by 15.89% under a power-priority strategy, thereby directly mitigating the carbon footprint of the pump station. The proposed hybrid computational framework in this study bridges the gap between the computationally expensive heuristic optimization and the strict real-time control requirements in engineering, highlighting its significant contribution to the sustainable and low-carbon operation of water infrastructure. Full article

Background: Iodine deficiency during pregnancy remains a leading cause of preventable neurodevelopmental impairment worldwide, yet quantitative characterization of the dose–response relationship between maternal iodine status and child neurodevelopment is lacking. Methods: A systematic search of PubMed, Embase, the Cochrane Library, and Web of Science was conducted for prospective cohort studies published up to February 2026 reporting associations between maternal iodine status and child neurodevelopmental outcomes across at least three exposure categories. All continuous effect estimates were converted to standardized mean differences (Hedges’ g) to permit pooling across heterogeneous assessment instruments, and meta-analyses were stratified by neurodevelopmental domain (cognitive, language, motor, behavior, academic). A two-stage dose–response meta-analysis was used to characterize non-linearity. Risk of bias was evaluated using the Newcastle–Ottawa Scale (NOS). Results: Ten prospective cohort publications corresponding to eight independent cohorts were included. After converting all continuous effect estimates to standardized mean differences (Hedges’ g) and consolidating the three overlapping MoBa publications into a single cohort, the pooled analysis revealed a significant negative association between suboptimal maternal iodine status and child neurodevelopmental performance (Hedges’ g = −0.13, 95% CI: −0.20 to −0.06, p < 0.001; I² = 95.2%). Domain-stratified analysis identified cognitive outcomes as most consistently affected (g = −0.22, 95% CI: −0.30 to −0.14; I² = 37.5%), followed by motor (g = −0.17; I² = 0%) and language outcomes (g = −0.16; I² = 92.5%), with between-domain heterogeneity explaining 38.6% of the total variance (p = 0.012). Binary outcome analysis confirmed increased odds of adverse neurodevelopmental outcomes (OR = 1.19, 95% CI: 1.03 to 1.39, p = 0.026). Subgroup analysis by iodine exposure indicator showed directionally consistent negative effects across dietary intake (g = −0.11), UIC (g = −0.11) and UI/Cr (g = −0.28), with no significant between-subgroup difference (p = 0.237). Exploratory dose–response modeling on the Hedges’ g scale suggested that neurodevelopmental performance in the fitted curves approached its maximum within a mid-range of dietary iodine intake (approximately 150–300 µg/d); however, the quadratic non-linearity terms did not reach statistical significance after cohort consolidation (p = 0.612 for dietary intake; p = 0.436 for UI/Cr), and these findings should therefore be interpreted as exploratory. Conclusions: Suboptimal maternal iodine status during pregnancy was associated with modest decrements in child neurodevelopmental performance, with exploratory dose–response analyses suggesting that the fitted curves approached their maximum within a mid-range of dietary iodine intake. Although statistical evidence for quadratic non-linearity was attenuated after consolidating overlapping cohorts, the directional pattern across indicators remained consistent with an inverted U-shaped relationship, supporting maintenance of adequate but not excessive iodine nutrition during pregnancy. Full article

Background: The integration of active breaks during the school day has been widely demonstrated to be effective in counteracting sedentary behaviors. The present study assessed the efficacy of a structured active breaks (ABs) intervention implemented during recess on multiple domains of Physical Literacy (PL) in primary-school children. Methods: A single-blind randomized controlled trial was conducted with 139 children (aged 9–10 years). Classes were randomized into an Experimental Group (EG, n = 66) and a Control Group (CG, n = 73). The EG participated in an 8-week intervention (six sessions/week, ~10 min) consisting of coordinative and interdisciplinary motor tasks during recess. Pre- and post-intervention assessments included physical fitness (SLJ, 4 × 10 m SR, 6MWT, MBT), gross motor skills (TGMD-2), selective attention (Bell Test), physical activity levels (PAQ-C), physical self-perception (PSP), and enjoyment (PACES). Results: A mixed-design MANOVA revealed a significant multivariate Time × Group interaction (p < 0.001). Univariate analyses showed significant improvements in the EG compared to the CG for explosive strength (p < 0.001), agility (p < 0.001), Gross Motor Quotient (p = 0.003), and selective attention (p < 0.001). Furthermore, the EG demonstrated significant increases in physical activity levels, self-perception, and enjoyment (p < 0.05). No significant gender interaction was found, indicating equal effectiveness for boys and girls. Conclusions: Transforming recess into a structured opportunity for movement through ABs effectively enhances physical, cognitive, and affective domains. This intervention represents a sustainable strategy for Health-Promoting Schools to foster PL and psychophysical well-being without reducing curricular instruction time. Full article

Background: Physical activity (PA), physical fitness (PF), and motor skills (MS) play crucial roles in overall health and well-being, particularly in early childhood, when habits that affect future health are formed. Methods: This study, involving 299 children (150 boys, 149 girls, mean age 6.9 ± 0.96 years), explored the variance explained by external factors such as socioeconomic status (SES), body composition (BC), sex, and geographical location on motor-related physical fitness (MRPF) and health-related physical fitness (HRPF) in children. Using a variety of assessments, including demographics, anthropometric data, BIA, ActiGraphs, the 20 m shuttle run, 10 and 20 m speed tests, and test items from the Körperkoordinations test für Kinder (KTK) and the TGMD-2, a multiple stepwise regression analysis using SPSS (v 28.0) identified the associated factors. Results: The variables tested show modest explained variance for HRPF, MRPF, and MS, with the largest cumulative explained variance of 26.4%. The explained variances for MRPF and MS were lower (medium to small) than the significant, medium-to-large, explained variances for HRPF. Body fat percentage (BF%), moderate-to-vigorous physical activity (MVPA), parental education and income, and BMI emerged as substantial contributors to HRPF, explaining 12.1% to 26.4% of the variance. Sex, BF%, and quintile status were the most influential associated factors for MRPF, and for MS, BMI and sex emerged as the strongest contributors. Conclusions: These findings underscore the importance of holistic approaches that consider individual factors, such as MVPA, body composition (BC), PA levels, sex, and broader social and economic contexts, to promote children’s well-being. The study emphasises the need for comprehensive strategies to address the multifaceted associations with children’s physical development. Full article

During the production, storage, and use of solid rocket motors, the impact generated by unexpected accidents, such as collision or drop, will cause damage to the propellant and affect the safety of the motor. However, the progressive evolution mechanism of mesoscopic damage in NEPE propellant under such impact conditions has not been fully elucidated, and there is still a lack of quantitative method to evaluate the impact-induced damage degree, which restricts the engineering safety assessment of solid rocket motors. To investigate the influence mechanism, the mesoscale damage characteristics of NEPE propellant under drop-weight impact is systematically studied. First, damaged NEPE specimens are obtained by conducting drop-weight experiments with a 10 kg hammer, where the drop height is varied to apply different impact impulses. The internal meso-structure of the propellant is then characterized using micro-CT, yielding detailed imagery of the refined meso-structural features and damage morphologies in the NEPE propellant. To capture the dynamic evolution process of mesoscale damage, a mesoscopic model incorporating AP, Al, HMX particles and voids, is subsequently constructed based on the high-precision mesoscopic morphology characterized by micro-CT. By integrating the deviatoric constitutive model, Gurson plastic damage model, and bilinear cohesive zone model, high-fidelity numerical simulations of the drop-weight impact damage process are performed using the advanced SPH-FEM coupling algorithm. The results indicate that no significant damage occurs when the impact impulse is less than 13.85 N·s. As the impulse increases, phenomena including matrix microcracks, void collapse, particle/matrix interface debonding, and main crack formation appear sequentially. When the impulse exceeds 24.25 N·s, particle fragmentation and transgranular fracture occur, accompanied by plastic flow and frictional heating that induce ignition. Finally, the overall damage degree is fitted by the Boltzmann function, and a function for quantitatively describing the damage degree is obtained, which can provide theoretical support for the impact safety assessment of solid rocket motors. Full article

Despite many efforts to curtail drunk driving, alcohol-related traffic fatalities and injuries continue to be a major public health problem in the United States (U.S.) and most of the world. Technologies exist that prevent an automobile from starting if the driver’s breath alcohol exceeds 20 milligrams per deciliter (mg/dL), but these devices are only fitted to vehicles of individuals who have been convicted of Driving Under the Influence (DUI). A new approach must be taken to reduce the incidence of drunk driving by integrating an alcohol sensor system in vehicles as part of the delivered hardware. The system must be fast, accurate, and contactless—meaning that a forced exhalation is not required to measure the concentration of alcohol on the breath. We report on a novel device, the Driver Alcohol Detection System for Safety (DADSS) Breath Alcohol Sensor System, which uses the mid-infrared region of the electromagnetic spectrum to concurrently monitor alcohol and expired carbon dioxide (CO₂) to accurately quantify the breath alcohol concentration in samples that have been diluted in the atmosphere before being measured. The system was validated in a research laboratory with 70 male and female volunteers in 187 individual study days. Participants were given various doses of alcohol to consume and then breath and blood samples were collected simultaneously. Pearson correlation coefficients between the DADSS Breath Alcohol Sensor system and blood samples indicate a strong correlation between the measures, with an overall Pearson correlation of 0.8875 over an alcohol concentration range of 0–220 mg/dL. These results indicate that incorporating the DADSS system into motor vehicles has the potential to reduce the incidence of drunk driving. Full article

Background: This study aimed to examine whether a physical education program based on the ecological dynamics approach, implemented through small-sided games (SSG), produces greater improvements in motor skills, daily physical activity levels, and perceived physical fitness in middle school students. Methods: Forty-eight students were assigned to an SSG group (ecological dynamics lessons including small-sided games, n = 26) or a Control group (traditional lessons based on teacher-centered instruction and analytical exercises, n = 22). The intervention lasted 12 weeks, with two sessions per week. Motor performance was assessed using the standing broad jump, 5-standing broad jump, 20 m sprint, 10 × 5 m shuttle run, 5-0-5 agility test, and sit-and-reach test. Daily physical activity was evaluated using the International Physical Activity Questionnaire—Short Form (IPAQ-SF), and perceived physical fitness was assessed using the Visual Analogue Fitness Perception Scale for Adolescents (FPVASA). Results: Significant group-by-time interactions were found in all motor tests. IPAQ-SF data revealed significant group-by-time interactions for vigorous and moderate physical activity. Perceived physical fitness showed significant group-by-time interactions for all items except flexibility. Conclusions: Physical education lessons structured according to the ecological dynamics approach and implemented through SSG-based protocols led to greater improvements than traditional methods. The dynamic and variable nature of SSG likely enhances neuromuscular stimulation, motor engagement, and motivation during physical education lessons. Full article

Background/Objectives: To evaluate the utility of phase angle (PhA) derived from bioelectrical impedance analysis as a screening indicator for pre-frailty in community-dwelling older adults. Methods: This cross-sectional study included 171 participants (36 men and 135 women) in Japan in 2023. PhA at 50 kHz was measured using bioelectrical impedance analysis and evaluated as a potential screening indicator for pre-frailty. Assessments included body composition, physical function tests (maximum walking speed, Timed Up and Go (TUG), grip strength, knee extension strength, and one-leg stance time with eyes open), cognitive function (MoCA-J), and the Motor Fitness Scale (MFS), a questionnaire assessing physical function, along with the Kihon Checklist (KCL). Frailty status was defined using KCL scores (4–7: pre-frailty; ≥8: frailty), and participants were classified into robust and pre-frail/frail groups. Results: PhA was significantly correlated with physical function measures, including grip strength (r = 0.54, p < 0.01), MFS (r = 0.36, p < 0.01), maximum walking speed (r = 0.20, p < 0.05), knee extension strength (r = 0.16, p < 0.05), and TUG (r = −0.17, p < 0.05). In women, logistic regression analysis showed that PhA was independently associated with pre-frailty (age-adjusted odds ratio: 2.38; 95% CI: 1.08–5.23; p < 0.05). ROC analysis yielded an area under the curve of 0.65 (95% CI: 0.56–0.74), indicating modest discriminative ability. Age-adjusted cutoff values of PhA were 4.19° and 4.74°, corresponding to points prioritizing sensitivity and specificity, respectively. Conclusions: PhA is associated with physical function and may serve as a simple, non-invasive indicator for identifying pre-frailty in community settings. However, given its modest discriminative ability, PhA alone may not be sufficient as a standalone screening tool and should be used in combination with other clinical indicators for clinical application. Full article

The new-generation aeration blower, which uses a high-speed permanent-magnet synchronous motor supported by elastic-foil thrust bearings, represents the future development trend of high-end sewage treatment turbomachinery. An axial load tester was designed for the elastic-foil thrust bearings in this study. Firstly, the relationship between the axial load and the elastic-foil thrust bearing parameters was first established. An axial load tester was designed. Secondly, finite-element simulation and strain calibration of the axial load tester were performed to estimate the linear relationship between the strain and the axial load. Then, the time histories of axial load for the high-speed permanent-magnet synchronous motor were further obtained at a rotational speed of 15,000 rpm during the operation tests. Finally, the load spectrum was compiled by fitting the test data to a function. The results showed that the amplitude and frequency of the load spectrum obeyed an exponential decay function. It can be used for the life test of elastic-foil thrust bearings in the future. The method for obtaining the axial load in the direct-driven turbomachinery was proposed. The axial load tester proposed in the present study, based on operation tests, proves valuable for improving the performance of the high-speed permanent magnetic synchronous motor and the elastic-foil thrust bearing. Full article

With population aging, motor vehicle accidents involving older drivers have increased. Age-related cognitive decline affects driving performance; however, the underlying neural mechanisms remain unclear. This scoping review explored neurophysiological characteristics associated with driving in older adults, including those at risk of dementia. Following PRISMA-ScR guidelines, we searched PubMed, Scopus, and CINAHL for studies examining driving-related neurophysiological measures in older adults aged ≥60 years. Twelve studies were included. Findings converge on load-dependent neural compensation failure: older adults maintain driving performance under low-to-moderate demands, but compensatory mechanisms break down under high cognitive load. Electroencephalography (EEG) studies revealed blunted midfrontal theta upregulation during high-load conditions, associated with reduced steering precision and delayed responses. Event-related potential studies demonstrated that reduced P3b amplitude was associated with missed braking responses and that abnormal visual evoked potentials in Alzheimer’s disease predicted unfit-to-drive classifications. fNIRS studies during driving-related tasks and an fMRI study using a laboratory-based visual task consistently showed prefrontal hyperactivation in older adults. Although some older adults maintained comparable performance to younger adults, the brain–behavior associations observed in younger adults were absent, suggesting that this hyperactivation does not necessarily serve a functional compensatory role. Combined with EEG evidence of impaired oscillatory modulation, these findings suggest that prefrontal hyperactivation does not necessarily compensate for diminished neural synchronization under high-load conditions. Neurophysiological markers hold promise for fitness-to-drive assessments. Future research should employ high-load scenarios and multimodal neuroimaging to verify prefrontal compensatory mechanisms. Full article

Background: Technology such as telerehabilitation, virtual reality, robotics, and wearable systems are reshaping pediatric physiotherapy. While evidence remains fragmented, there is little guidance on how these approaches can be integrated into coherent, family-centered care pathways. Objective: To develop the Digital Pediatric Physiotherapy Framework (DPPF) based on a systematic review of randomized evidence on digital interventions in pediatric physiotherapy. Methods: Several databases were searched for randomized trials published after 1 January 2020, including PubMed, Web of Science Core Collection, and Google Scholar. The included studies assessed the results of physiotherapist-delivered or physiotherapist-supervised digital interventions in children and adolescents aged 18 and younger. Population, intervention, outcome, implementation, and safety data were extracted. Considering the substantial heterogeneity of the findings, they were synthesized narratively. Cochrane RoB 2 was used to assess risk of bias, and GRADE was used to evaluate certainty of evidence. Results: Twenty-nine trials involving 1196 participants were included. Most studies examined virtual reality and gaming-based interventions, with fewer evaluating telerehabilitation/tele-exercise and robotic or wearable technologies. Digital interventions were most often directed at body-function and activity-level outcomes, while participation outcomes were less frequently studied. The strongest evidence supported short-term benefits in balance, gross motor function, upper-limb activity, pain, and selected fitness outcomes, particularly in children with cerebral palsy. Evidence for telerehabilitation and robotic or wearable approaches was more limited but generally promising. Implementation, equity, cost, and long-term outcomes were rarely reported. No eligible trial directly evaluated electronic patient-reported outcome measures, digital triage, or clinical decision support as stand-alone interventions. Conclusions: Digital interventions have the potential to strengthen pediatric physiotherapy, particularly for short-term motor and functional outcomes. The proposed DPPF provides an implementation-informed structure to guide future research, pathway design, and more purposeful integration of digital health into pediatric rehabilitation practice. Full article

When the Risley prism pair is used for target tracking, the nonlinear relationship between beam deflection and prism rotation makes tracking performance highly dependent on precise and stable motor control over a wide speed range. Although the brushless DC motor serves as the preferred drive source, its inherent commutation torque ripples directly induce beam pointing jitter, severely degrading overall tracking accuracy and stability. To address these issues, this paper proposes a three-vector-based model predictive direct speed control method. This approach establishes a direct speed-to-torque control channel by generating reference active power through dynamic equations, eliminating the need for fitting a constant flux linkage and parameter tuning. Simultaneously, combined with three-vector optimization and seven-segment modulation strategies, it achieves a dynamic balance between high-frequency, instantaneous electromagnetic power fine-tuning and inherent mechanical inertia of the rotor. Simulation results demonstrate that the proposed method exhibits superior speed stability compared to the conventional double-vector-based model predictive power control method and maintains high-precision dynamic tracking over a wide speed range. Ultimately, it leads to an average reduction of over 60% in the time-weighted absolute tracking error integral under various target trajectories, providing an effective solution for drive control of target tracking in Risley prism systems. Full article