Search Results (264)

The fatigue behaviour of a 90° long radius elbow, which is adjacent to the feedwater nozzle in a BWR, was analyzed. The start-up and shutdown transients were considered. A thermo-mechanical finite element analysis was carried out to determine the stresses induced by thermal transients, considering the environmental conditions in the reactor feedwater pipe. In addition, the Palmgren–Miner methodology and the ASME B&PVC code fatigue curve were applied to evaluate the accumulated damage and service life of the component. Environmental correction factors were considered to estimate environmentally assisted fatigue. Reductions in fatigue life were observed. In the second part of this paper, a part-through thickness semielliptical crack was also postulated in the internal surface of the elbow. It was aligned along the axial direction at the crown zone. Its growth was modelled using the Paris equation, evaluating the risk of failure using fracture parameters. It was found that the vulnerable area is located on the inner surface of the elbow, due to the concentration of stress caused by the curved geometry. Failure assessment diagrams (FADs) were plotted. It was found that the crack depth is the main factor governing crack behaviour under the conditions studied. The results provide a methodology for assessing the integrity of pipes subjected to specific environmental and operating conditions. Full article

Background/Objectives: Joubert syndrome is a rare neurodevelopmental disorder characterized by congenital cerebellar and brainstem malformations affecting networks involved in predictive motor control, sensorimotor integration, and autonomic regulation, resulting in a heterogeneous motor phenotype. Functional impairment is typically described using global gross motor scores, which may not adequately reflect axial control, postural organization, musculoskeletal alignment, or respiratory–postural interactions. The objective of this descriptive pilot case series was to provide a multidimensional functional characterization of children with Joubert syndrome by integrating standardized motor assessments with postural, musculoskeletal, and thoracoabdominal measures. Methods: Six children with genetically and radiologically confirmed Joubert syndrome underwent a single standardized assessment session conducted by the same examiner. This cross-sectional, non-controlled study was based on feasibility sampling, and no a priori power calculation was performed. Gross motor function and postural control were evaluated using the Gross Motor Function Measure-88 and the Balance Assessment Rating Scale. Additional measures included joint range of motion, sacral inclination angle, thoracic configuration, thoracic excursion during quiet breathing, and respiratory rate. Analyses were limited to descriptive statistics. Results: Gross motor performance varied widely across participants, whereas postural control scores did not parallel gross motor performance levels within the cohort. Inter-individual variability was observed in joint mobility, pelvic alignment, and thoracoabdominal configuration, including among children with relatively preserved gross motor scores. Thoracic excursion during quiet breathing demonstrated a relatively narrow and low within-cohort range. Conclusions: In this small exploratory case series, functional characteristics observed in this cohort extended beyond global motor scores. Axial control, postural organization, and thoracoabdominal configuration may represent relevant descriptive domains of functional presentation within a multidimensional framework. Larger, longitudinal, and controlled studies are required to determine their clinical and neurodevelopmental significance. Full article

Background/Objectives: In pole vaulting, the capacity to store elastic energy within the pole (E_pole) significantly influences performance. This study investigated the characteristics of E_pole storage by analyzing the box reaction force and vector angle. Methods: Eight male pole vaulters, including World Championships participants, were examined. A motion capture system (VICON) and force plates (Kistler) were used to measure the vector angle (angle between the compression force (CF) and box reaction force vectors) and horizontal velocity of the center of gravity (COG) (Vcogh). E_pole was calculated as the integral of the CF (estimated from the box reaction forces), and pole bending displacement. The relationships between each variable and the peak height of COG (HP) were assessed using Pearson’s product–moment correlation coefficients. Results: HP correlated with Vcogh in the pole plant (PP) (r = 0.82) and E_pole (r = 0.94). Vaulters with a higher HP maintained a vector angle < 2° between 20% and 80% of the pole bending phase, indicating closer directional alignment between the box reaction force vector and pole chord direction, whereas vaulters with lower HP exhibited larger vector angles (4–8°), associated with a relative reduction in the axial component of force transmitted to the pole. Conclusions: A smaller vector angle effectively enhanced the CF, thereby increasing pole bending and promoting greater accumulation of E_pole. Therefore, maintaining a small vector angle may enable more effective force transmission along the pole chord, and vector angle characteristics and PP horizontal velocity may assist appropriate pole selection and training strategies to enhance elastic energy storage and performance. Full article

Screw-drive in-pipe robots are widely used for inspection and maintenance of pipeline infrastructure because their tilted-wheel locomotion enables continuous traversal of horizontal, vertical, and curved pipes. However, most existing designs rely on passive spring mechanisms to generate wall-contact forces, making traction performance highly sensitive to pipe-diameter variations, friction changes, and manufacturing tolerances. This paper presents an adaptive screw-drive in-pipe robot that integrates adjustable radial geometry, embedded Hall-effect force sensing, and closed-loop gripping-force control. A unified mechanical–geometric model is developed to describe the coupling between actuator displacement, spring compression, wheel-tilt geometry, and pipe-diameter variation. Based on this model, a minimum safe gripping-force condition is derived and used to define a reference force for real-time control. A proportional–derivative controller regulates the gripping force of the front traction module, while a rear stabilizing module ensures axial alignment and suppresses body rotation. Simulation results under realistic diameter transitions and external disturbances demonstrate stable force regulation, preservation of a positive traction margin, and reduced unnecessary actuator effort. The proposed approach enables robust and energy-aware screw-drive locomotion in variable-diameter pipelines. A physical prototype of the robot has been fabricated to support the forthcoming experimental campaign; however, the validation presented in this study is limited to modeling and simulation, with experimental evaluation planned for future work. Full article

Intelligent Clinical Decision Support Systems (ICDSS) are increasingly integrated into healthcare settings to enhance clinical decision-making, efficiency, and patient safety. Despite advances in artificial intelligence-enabled decision support, ICDSS adoption remains inconsistent, particularly in complex clinical environments where professional autonomy, workflow alignment, and accountability are critical. This study examines healthcare providers’ perspectives on ICDSS through a grounded theory approach informed by established Information Systems theories, including the Unified Theory of Acceptance and Use of Technology (UTAUT), Technology Acceptance Model (TAM), Diffusion of Innovation (DOI), and the Human-Organization-Technology fit (HOT-fit) framework. Semi-structured interviews were conducted with 11 providers within a large, integrated healthcare organization, and data were analyzed using open, axial, and selective coding. The findings reveal three interrelated dimensions shaping ICDSS use: provider experience, clinical utility, and adaptation. While ICDSS were perceived as valuable for improving efficiency, supporting treatment decisions, and enhancing patient safety, their adoption was constrained by cognitive overload, workflow misalignment, data quality concerns, and perceived threats to professional autonomy. Trust, explainability, and workflow fit emerged as central mechanisms influencing selective use rather than full adoption. By grounding provider perspectives within a sociotechnical lens, this study extends existing IS theories to the context of AI-enabled clinical decision support and offers empirically grounded insights for designing ICDSS that better align with clinical practice. Full article

Axial postural abnormalities in Parkinson’s Disease (PD) are traditionally assessed using clinical rating scales, although picture-based assessment is considered the gold standard. This study evaluates the reliability and clinical relevance of two markerless body-tracking frameworks, the RGB-D-based Microsoft Azure Kinect (providing the reference KIN_3D model) and the RGB-only Google MediaPipe Pose (MP), using a synchronous dual-camera setup. Forty PD patients performed a 60 s static standing task. We compared KIN_3D with three MP models (at different complexity levels) across horizontal, vertical, sagittal, and 3D joint angles. Results show that lower-complexity MP models achieved high congruence with KIN_3D for trunk and shoulder alignment (ρ > 0.75), while the lateral view significantly improved tracking of sagittal angles (ρ ≥ 0.72). Conversely, the high-complexity model introduced significant skeletal distortions. Clinically, several angular parameters emerged as robust metrics for postural assessment and global motor impairments, while sagittal angles correlated with motor complications. Unexpectedly, a more upright frontal alignment was associated with greater freezing of gait severity, suggesting that static postural metrics may serve as proxies for dynamic gait performance. In addition, both RGB-only and RGB-D frameworks effectively discriminated between postural severity clusters. While the higher-complexity MP model should be avoided due to inaccurate 3D reconstructions, our findings demonstrate that low- and medium-complexity MP models represent a reliable alternative to RGB-D sensors for objective postural assessment in PD, facilitating the widespread application of objective posture measurements in clinical contexts. Full article

Misalignment of the herringbone groove radial bearing can lead to changes in performance and system abnormalities. To investigate the effects of different misalignment modes and magnitudes on the HGJB-rotor system, a coupled dynamic model was established. Based on this model, the influences of parallel misalignment and angular misalignment on bearing performance were analyzed, and the variation law of rotor vibration was revealed. The results indicate that the rotor motion trajectory and bearing dynamic coefficients (including critical journal mass and critical whirl frequency) exhibit time-varying characteristics. Specifically, compared with the aligned condition, a parallel misalignment of δ = 8.0 × 10⁻⁶ m reduces the relative film thickness by 17.8% and increases the maximum film pressure by 1.85%. Meanwhile, an angular misalignment of θ₀ = 8.0 × 10⁻⁴ rad results in a 45.9% reduction in relative film thickness and a 33.1% increase in maximum film pressure. Additionally, the increased misalignment magnitude enhances the rotor vibration amplitude significantly. For instance, the Y-direction displacement amplitude increases by 59.4% under the maximum parallel misalignment. Moreover, the misalignment also alters the axial trajectory of the rotor. Overall, different misalignment modes and magnitudes exert significant effects on the rotor vibration characteristics. The research findings provide theoretical support and technical references for the further development and engineering application of HGJBs. Full article

Through finite-element simulation, the axial potential distribution of the ion trap is analyzed. The effects of the central hole diameter of the end cap and the spacing between the two end caps on the axial geometric parameters of the ion trap are investigated. Based on these findings, a set of linear Paul traps is designed by selecting suitable end caps and quadrupoles. Stable trapping of calcium ions (Ca⁺) is successfully achieved, and these ions are subsequently laser-cooled into ionic Coulomb crystals. In the experiment, secular motion excitation of the Ca⁺ ion Coulomb crystal is performed, yielding an axial geometric parameter of 0.115(1) for the ion trap. This value aligns well with the simulation result of 0.114(2). The precise determination of the axial geometric parameter provides a solid foundation for subsequent high-precision optical or mass spectrometry measurements. Full article

A twin-screw multiphase pump is essential equipment for the transfer of gas-liquid multiphase mixtures in oil and gas operations. This work addresses rotor deformation in real applications by correcting the rotor profile using the arc transition approach, eliminating teeth tips, mitigating local stress concentration, and reducing the danger of rotor deformation. Simultaneously, in conjunction with the oil and gas mixed transportation requirements of the Changqing Oilfield, the MPC208-67 twin-screw mixed transportation pump was engineered, and the essential structural specifications were established. This paper employs the Mixture multiphase flow model and the SST k-ω turbulence model to simulate the internal flow field of the pump in Changqing Oilfield, aiming to examine the impact of high-gas-content conditions on the pump’s performance and ensure it aligns with design specifications. The modeling findings indicate that the pressure in the pump progressively rises along the axial direction and remains constant within the chamber. As the void fraction of the medium increases, the pressure differential between the inlet and exit of the rotor fluid domain progressively diminishes, resulting in high-velocity fluid emerging in the interstice between driving and driven rotors. The simultaneous increase in rotational speed elevates the overall fluid velocity while diminishing the pressure value. Under rated conditions, the output pressure and flow rate of the planned multiphase pump achieve 1.8 MPa and 300 m³/h, respectively, thereby fully satisfying the design specifications. This work employs the response surface approach to optimize multi-objective performance parameters, including leakage and pressurization capacity, to enhance the pump’s operational performance under high gas content situations. The optimization results indicate a 17.87% reduction in pump leakage, an 8.86% rise in pressurization capacity, and a substantial enhancement in pump performance. Full article

Recent advances in cultured-meat research emphasize the development of edible scaffolds that promote myogenic differentiation. Nonetheless, many materials provide only structural support and do not replicate native muscle or serve as alternatives to muscle–adipocyte co-culture, highlighting the need for cytocompatible, tissue-specific scaffolds. This study aimed to develop a composite alginate–zein (Algi/zein) hydrogel enriched with myotube (MP) and adipocyte (AP) powders to provide a structural, biochemical, and potentially cultured-meat hydrogel. Algi/zein hydrogels enriched with myotube (MP) and adipocyte (AP) powders were fabricated and evaluated for structural, cellular, and biochemical properties using C2C12 myoblasts cultured in 2D and 3D environments. Metabolite profiling was performed to evaluate the biochemical features. MP/AP incorporation generated extra cellular matrix (ECM)-like microstructures and significantly enhanced myotube alignment in Algi/zein scaffolds compared with MP/AP-free controls, increasing the proportion of axially aligned fibers by up to ~6-fold at a 1:1 AP:MP ratio. Organized myosin expression was observed, while metabolomic profiling indicated partial biochemical similarity to beef. Incorporating MP and AP into Algi/zein hydrogels enhanced myotube alignment and showed partial structural and biochemical similarity to native muscle tissue. Full article

Fiber actuators underpin soft robots, artificial muscles, and smart textiles. A persistent bottleneck is the fabrication of monodomain liquid crystal elastomer (LCE) microfibers with narrow size distributions while preserving axial alignment. This work establishes a melt-centrifugal spinning (MCS) route with two-step UV fixation that separates flow-induced alignment from network crosslinking. High-speed rotation creates a long extensional jet; an obliquely incident, on-the-fly UV dose at touchdown locks the director, and a post-cure consolidates the network. The obtained LCE microfiber can achieve large reversible contraction (L/L₀ = 0.56), lift a weight, and trigger the tweezers. The method produces a new approach for the fabrication of device-ready LCE actuators, establishes a general design principle for diameter control via curing sequence, and opens a practical path toward artificial muscles and flexible micro robotics. Full article

High-sensitivity, high-resolution electric field sensors (EFS) find extensive applications across multiple domains, including atmospheric monitoring, aerospace, power grid management, and industrial automation. While conventional electric field measurement techniques suffer from integration challenges and high-power consumption, micro-electromechanical systems (MEMS)-based EFS offer distinct advantages through miniaturization, integration capability, and functional intelligence. This research incorporates frequency modulation technology into MEMS EFS, leveraging its inherent noise immunity, long-range transmission capacity, and compatibility with digital systems to enhance measurement precision. The sensor’s lateral and axial symmetry configurations are systematically investigated to reveal how asymmetric stiffness perturbations (negatives vs. positives) optimize performance, aligning with symmetry principles in MEMS design. Experimental results demonstrate that the lateral configuration achieves optimal performance with a sensitivity of 0.091√Hz/(kV/m) and a resolution of 1.01 kV/m, whereas the axial configuration yields an average sensitivity of 0.038 √Hz/(kV/m) with a corresponding resolution of 2.37 kV/m. The measurement range of the sensor is from −193.4 kV/m to 193.4 kV/m. Full article

Remote sensing image segmentation requires balancing global context and local detail across multi-scale objects. However, convolutional neural network (CNN)-based methods struggle to model long-range dependencies, while transformer-based approaches suffer from quadratic complexity and become inefficient for high-resolution remote sensing scenarios. In addition, the semantic gap between deep and shallow features can cause misalignment during cross-layer aggregation, and information loss in upsampling tends to break thin continuous structures, such as roads and roof edges, introducing pronounced structural noise. To address these issues, we propose lightweight Lite-BSSNet (Blueprint-Guided State Space Network). First, a Structural Blueprint Generator (SBG) converts high-level semantics into an edge-enhanced structural blueprint that provides a topological prior. Then, a Visual State Space Bridge (VSS-Bridge) aligns multi-level features and projects axially aggregated features into a linear-complexity visual state space, smoothing high-gradient edge signals for sequential scanning. Finally, a Structural Repair Block (SRB) enlarges the effective receptive field via dilated convolutions and uses spatial/channel gating to suppress upsampling artifacts and reconnect thin structures. Experiments on the ISPRS Vaihingen and Potsdam datasets show that Lite-BSSNet achieves the highest segmentation accuracy among the compared lightweight models, with mIoU of 83.9% and 86.7%, respectively, while requiring only 45.4 GFLOPs, thus achieving a favorable trade-off between accuracy and efficiency. Full article

Sustainability assessment in UNESCO World Heritage city centres often treats spatial configuration, functional accessibility, and heritage governance as separate analytical domains. This study addresses this fragmentation by developing a composite assessment framework to evaluate morphological sustainability in historic urban cores. The Morphological Sustainability Model (MSM) and its numerical expression, the Morphological Sustainability Index (MSI), are applied to the Bursa Khans District for the 2020–2025 period. The model integrates Space Syntax variables (integration, connectivity, choice, and intelligibility), 15-Minute City indicators related to proximity, pedestrian accessibility, active mobility, and inclusivity, and Historic Urban Landscape-based governance evaluations derived from UNESCO-compliant management plans. These components are synthesised into six weighted composite indicators (BKH1–BKH6). Results show that the MSI increases from 0.38 in 2020 to 0.51 in 2025 (+34.2%), indicating a strengthened alignment between spatial configuration, pedestrian-oriented functional performance, and heritage governance capacity. The findings reveal a shift from car-oriented axial dominance toward a more pedestrian-centred spatial structure along the historic bazaar spine. Overall, the study demonstrates that the MSI provides a transferable, decision-support-oriented framework for assessing morphological sustainability in historic urban environments. Full article

Driven by societal and technological progress, the polymer tubing industry is increasingly focused on sustainable and biodegradable products, with polylactic acid (PLA)-based microtubes gaining attention for applications such as medical stents and disposable straws. However, their inherent mechanical limitations, especially under hoop loading and the brittleness of PLA, restrict broader use. Although two-dimensional nanofillers can enhance polymer properties, conventional extrusion only creates uniaxial alignment, leaving fillers randomly oriented in the radial plane and failing to improve hoop performance. To address this, we developed a rotational extrusion strategy that superimposes a rotational force onto the conventional axial flow, generating a biaxial stress field. By adjusting rotational speed to regulate hoop stress, a concentric, interlocked graphene oxide network in a PLA/polybutylene adipate terephthalate microtube is induced along the circumferential direction without disturbing its axial alignment. This architecturally tailored structure significantly enhances hoop mechanical properties, including high compressive strength of 0.54 MPa, excellent low-temperature impact toughness of 0.33 J, and improved bending resistance of 30 N, while maintaining axial mechanical strength exceeding 50 MPa. This work demonstrates a scalable and efficient processing route to fabricate high-performance composite microtubes with tunable and balanced directional properties, offering a viable strategy for industrial applications in medical, packaging, and structural fields. Full article