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Adolescent idiopathic scoliosis (AIS) is a three-dimensional growth disorder. Corrective surgical procedures are the recommended treatment option for a thoracic angle exceeding 50° and a lumbar major curve of 40°. Over the past few years, dynamic growth modulation implants have been developed as alternatives to permanent fusion. The ApiFix system was designed as a 2D “posterior dynamic device” for curve correction. After implantation in a minimally invasive procedure, it uses polyaxial joints and a self-adjusting rod to preserve the degree of motion and to accommodate the patient’s growth. It provides an effective method of controlling deformity and fills the gap between the conservative treatment of major curves that are >35° and the fusion procedure. The objective of the two-center cohort study was the analysis of the correction results of patients, who underwent surgical intervention with the ApiFix system. The inclusion criteria were AIS, Lenke type 1 or type 5, a major curve on bending films of ≤30°, and an angle of the major curve of between 35° and 60°. Postoperative radiograph data were obtained longitudinally for up to 24 months of follow-up and compared to preoperative (preop) values. For comparisons of the different time points, non-parametric tests (Wilcoxon) or paired t-tests for normally distributed values were used to analyze repeated measures. Overall, 36 patients (25 female and 11 male) were treated with the ApiFix system from April 2018 to October 2020. Lenke type 1 was identified in 21 (58%) cases and Lenke type 5 was identified in 15 (42%) cases. The average angle of the thoracic major curve for Lenke 1 was 43°. The preoperative lumbar major curve (Lenke 5) was determined to be 43°. Over a follow-up of 24 months, a correction of the major curve to an average of 20° was observed for Lenke 1 and that to an average of 15° was observed for Lenke 5. Lenke type 1 and type 5 showed significant changes in the major curve over the individual test intervals in the paired comparisons compared to the starting angle (Lenke 1: preop—24 months, 0.002; Lenke 5: preop—24 months, 0.043). Overall, 11 events were recorded in the follow-up period, that required revision surgery. We distinguished between repeated interventions required after reaching the maximum distraction length of the implant due to the continued growth of the patient (n = 4) and complications, such as infections or problems associated with the anchorage of the implant (n = 7). The results from the present cohort revealed a statistically significant improvement in the postoperatively measured angles of the major and minor curves in the follow-up after 24 months. Consequently, the results were comparable to those of the already established vertebral body tethering method. Alignment in AIS via dynamic correction systems in combination with a possible growth modulation has been a treatment alternative to surgical fusing procedures for more than a decade. However, the long-term corrective effect has to be validated in further studies.

The ‘long tail’ nature of rural special education (RSE) suggests that it simultaneously possesses the private nature of discreteness and the public nature of externalities, which can easily cause provision insufficiency. However, this mismatch may have a dynamic intertemporal correction mechanism impacted by different expenditures of supply sectors (governments and other social sectors). This paper uses different models and data from 30 provinces in China from 2003–2014 to analyze this dynamic correction mechanism. This research finds that different kinds of expenditures from different suppliers have divergent effects on this correction. Capital expenses (especially infrastructure construction) have significantly positive effects on the correction, but administrative expenses have significant dual effects on the correction. These effects may be caused by the various governance efficiencies and motivations of all stakeholders in RSE. This paper concludes that we should pay more attention to the accurate recognition and effective satisfaction of RSE affected by the governance efficiency and motivation of different suppliers to achieve this dynamic correction.

This article mainly studies the spoofing attack problem faced by the Beidou system, with a focus on the detection and mitigation methods of the second type of time synchronization attack. We propose a clock decomposition method based on the fusion of the binomial model and Kalman filter using time series clock decomposition. This method decomposes the clock bias sequence into trend and residual terms, uses a sliding window weighted least squares fitting binomial model to capture long-term trends, and dynamically tracks the short-term fluctuations of residual terms through Kalman filtering, achieving high-precision prediction of clock bias and dynamic correction of attack errors. The results indicate that the root mean square error of the improved method is reduced by one order of magnitude compared to the traditional binomial model.

A common format is developed for a mass and an inerter-based resonant vibration absorber device, operating on the absolute motion and the relative motion at the location of the device, respectively. When using a resonant absorber a specific mode is targeted, but in the calibration of the device it may be important to include the effect of other non-resonant modes. The classic concept of a quasi-static correction term is here generalized to a quasi-dynamic correction with a background inertia term as well as a flexibility term. An explicit design procedure is developed, in which the background effects are included via a flexibility and an inertia coefficient, accounting for the effect of the non-resonant modes. The design procedure starts from a selected level of dynamic amplification and then determines the device parameters for an equivalent dynamic system, in which the background flexibility and inertia effects are introduced subsequently. The inclusion of background effect of the non-resonant modes leads to larger mass, stiffness and damping parameter of the device. Examples illustrate the relation between resonant absorbers based on a tuned mass or a tuned inerter element, and demonstrate the ability to attain balanced calibration of resonant absorbers also for higher modes.

As the core equipment for industrial material lifting, the safe operation of bridge cranes is essential to ensuring production efficiency. A five-dimensional digital twin model framework is proposed for the full lifecycle management of bridge cranes to address the lack of real-time performance and lifespan prediction in traditional detection methods that rely on manual inspection and static evaluation. The digital twin model supports real-time mapping and dynamic correction of the crane's operating status, established through multidimensional fusion of the physical entity layer, virtual model layer, twin data layer, connection layer, and service function layer. And analyzed that the model involves the key technology: physical virtual model synchronous operation and interaction technology. Analyzed the application of predicting the remaining life of key components, based on the digital twin model combined with convolutional neural network (CNN) and gated neural network (GRU), providing theoretical support and engineering practice reference for bridge crane’s intelligent operation and safety control.

To address the problems of low computational efficiency and large deviations between simulation models and physical experiments in traditional virtual vibration test analysis, this paper proposes a virtual vibration test analysis system based on a CPU+GPU computing architecture and incorporating virtual-real fusion model correction technology. A hierarchical task scheduling strategy is designed, allocating logical tasks to the CPU and deploying computationally intensive vibration simulation tasks to the GPU. A bidirectional feedback mechanism between physical experiments and numerical simulations is established through virtual-real fusion model correction, enabling dynamic correction and accuracy improvement of the simulation model. Experimental verification shows that the system’s computational efficiency is approximately 82% higher than that of the traditional pure CPU architecture. After correction, the results of digital vibration table tests are very close to those of physical vibration table tests. This provides a solution for high-precision, high-efficiency virtual vibration testing in aerospace, automotive, and mechanical fields, and has significant engineering application value.

A moving static pressure distribution is commonly used to simulate a travelling ship. However, the ship movement changes the fluid velocity around the hull, inducing pressures on the hull surface that are no longer equal to the static pressure. Therefore, we introduce a dynamic pressure correction strategy, which can accurately simulate the impact of the ship movement on the hull-surface pressure and preserve the desired hull shape under both stationary and transient conditions. The strategy is applied to a high-order spectral model and used to investigate ship-induced waves and wave resistance over a both flat and variable topography. We explore various parameters in our study, including the average water depth to ship draft ratio ($h_0/d$), the channel width to ship width ratio ($W/B$), the Froude number ($Fr_0=U/\\sqrt {gh_0}$) and variations in bathymetric slope. Compared with experiments on a flat bottom, the numerical results with dynamic correction show better accuracy in the simulation of ship-induced waves and wave resistance than those obtained using a static pressure distribution. The correlation coefficient for wake waves between the numerical and experimental results is improved by approximately 0.25 with the dynamic correction strategy. The amplitude and wavelength of ship-induced mini-tsunamis over a variable topography are found to be reduced when employing a dynamic correction compared with a static pressure distribution, and this effect becomes more pronounced with higher Froude number. The static pressure approach is shown to allow large deformations of the desired hull shape and changes in ship volume which are responsible for the different wave patterns from the two approaches.

The dynamic fracture properties of porous ceramics were studied using single bunch synchrotron X-ray phase contrast imaging. The modified brazilian geometry was used to initiate and propagate a pure mode I crack. The specimen was compressed using the Split Hopkinson bars at strain rates of the order of 102 s-1. Main cracks were isolated for four different grades of Al2O3, one dense alumina, and three porous grades with 20% to 60% porosity. The maximum measured crack velocities for three grades is of the order of 0.6cR and 0.4cR for the most porous. The fracture energy was estimated using a FE numerical simulation to quantify the influence of inertial effects induced by crack propagation. The results show that these inertial effects are far from negligible (up to 80% of the stored energy) and that the dynamic correction factors known from the literature tend to overestimate the fracture energy. The values obtained vary from 22 J/m2 for the densest to 5 J/m2 for the most porous.

To address the low recognition accuracy and high misclassification rate of existing models caused by the highly dynamic, strongly coordinated, and rhythm-bound characteristics of cheerleading movements, this study improves a Pose-based Convolutional Neural Network 3D (PoseConv3D). By embedding three core modules-dynamic skeletal correction, multi-scale spatiotemporal encoding, and motion rhythm perception integrating a dual-path classification layer, the proposed method achieves joint output of action categories and difficulty coefficients. Experiments conducted on a public benchmark dataset demonstrate that the proposed model attains an accuracy of 93.2%, representing improvements of 11.5% and 8.5% over the Spatial-Temporal Graph Convolutional Network (ST-GCN) and the original PoseConv3D, respectively. The dynamic correction module reduces joint drift error by 42.3%, while the rhythm perception module lowers the misclassification rate of “wave/kick” movements by 12.7%. Additionally, an inference speed of 88.2 frames per second meets real-time application requirements. The main contributions of this work are threefold. First, a novel dynamic-rhythm fusion recognition framework is proposed. By incorporating a rhythm-aware temporal attention mechanism and a confidence-guided skeletal correction strategy, the framework effectively addresses two key limitations of existing approaches: the insufficient modeling of temporal rhythm in graph neural networks (e.g., ST-GCN) and the poor robustness of Transformer-based methods (e.g., PoseFormer) to joint drift under high-dynamic conditions. Second, a closed-loop “recognition-difficulty quantification” system tailored to cheerleading is constructed. Finally, the proposed framework offers a transferable solution for the recognition of high-dynamic sports movements, providing methodological support for broader applications in complex action analysis.

Ten years of terrestrial water storage anomalies from the Gravity Recovery and Climate Experiment (GRACE) were used to estimate high-latitude snowfall accumulation using a mass balance approach. The estimates were used to assess two common gauge-undercatch correction factors (CFs): the Legates climatology (CF-L) utilized in the Global Precipitation Climatology Project (GPCP) and the Fuchs dynamic correction model (CF-F) used in the Global Precipitation Climatology Centre (GPCC) monitoring product. The two CFs can be different by more than 50%. CF-L tended to exceed CF-F over northern Asia and Eurasia, while the opposite was observed over North America. Estimates of snowfall from GPCP, GPCC-L (GPCC corrected by CF-L), and GPCC-F (GPCC corrected by CF-F) were 62%, 64%, and 46% more than GPCC over northern Asia and Eurasia. The GRACE-based estimate (49% more than GPCC) was the closest to GPCC-F. We found that as near-surface air temperature decreased, the products increasingly underestimated the GRACE-based snowfall accumulation. Overall, GRACE showed that CFs are effective in improving GPCC estimates. Furthermore, our case studies and overall statistics suggest that CF-F is likely more effective than CF-L in most of the high-latitude regions studied here. GPCP showed generally better skill than GPCC-L, which might be related to the use of satellite data or additional quality controls on gauge inputs to GPCP. This study suggests that GPCP can be improved if it employs CF-L instead of CF-F to correct for gauge undercatch. However, this implementation requires further studies, region-specific analysis, and operational considerations.