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12 pages, 783 KiB  
Case Report
Accelerating Recovery: A Case Report on Telerehabilitation for a Triathlete’s Post-Meniscus Surgery Comeback
by Olimpio Galasso, Mariaconsiglia Calabrese, Giuseppe Scanniello, Marina Garofano, Lucia Pepe, Luana Budaci, Gaetano Ungaro, Gianluca Fimiani, Placido Bramanti, Luigi Schiavo, Francesco Corallo, Maria Pagano, Irene Cappadona, Alessandro Crinisio and Alessia Bramanti
Healthcare 2025, 13(4), 406; https://doi.org/10.3390/healthcare13040406 (registering DOI) - 13 Feb 2025
Abstract
Introduction: Meniscus injuries are common among endurance athletes, requiring structured rehabilitation to restore function and facilitate a safe return to sport. Traditional in-person rehabilitation may not always be accessible or feasible for high-performance athletes. Telerehabilitation, incorporating virtual reality, motion tracking, and telemonitoring, offers [...] Read more.
Introduction: Meniscus injuries are common among endurance athletes, requiring structured rehabilitation to restore function and facilitate a safe return to sport. Traditional in-person rehabilitation may not always be accessible or feasible for high-performance athletes. Telerehabilitation, incorporating virtual reality, motion tracking, and telemonitoring, offers an innovative approach to guided recovery. However, evidence supporting its effectiveness in elite athletes remains limited. Case presentation: This case report explores the application of an innovative telerehabilitation program for a 49-year-old triathlete recovering from partial meniscectomy following a medial meniscus tear. The program was structured into three progressive phases over 12 weeks, focusing on restoring range of motion (ROM), muscle strength, and functional stability while gradually reintroducing sports-specific activities. Results: By the end of the rehabilitation, the patient achieved full ROM and muscle strength (scoring 5/5 on the Medical Research Council scale for the vastus medialis), along with a pain-free state in both static and dynamic conditions. The integration of telemonitoring devices facilitated detailed monitoring and feedback, enabling personalized adjustments to the rehabilitation protocol. Key milestones included a return to swimming and cycling in Phase 2, reintroduction of running in Phase 3, and a full resumption of triathlon training by week 12. Conclusion: Despite the positive results, the study highlights the need for further research to validate these findings across larger cohorts and establish standardized telerehabilitation protocols for athletes. This case underscores the potential of digital health technologies in enhancing recovery trajectories for high-demand athletes post-meniscus surgery, paving the way for supervised, accelerated, and effective sports reintegration. Full article
(This article belongs to the Special Issue Sports Trauma: From Prevention to Surgery and Return to Sport)
28 pages, 2083 KiB  
Article
Pipe Routing with Topology Control for Decentralized and Autonomous UAV Networks
by Shreyas Devaraju, Shivam Garg, Alexander Ihler, Elizabeth Serena Bentley and Sunil Kumar
Drones 2025, 9(2), 140; https://doi.org/10.3390/drones9020140 (registering DOI) - 13 Feb 2025
Abstract
This paper considers a decentralized and autonomous wireless network of low SWaP (size, weight, and power) fixed-wing UAVs (unmanned aerial vehicles) used for remote exploration and monitoring of targets in an inaccessible area lacking communication infrastructure. Here, the UAVs collaborate to find target(s) [...] Read more.
This paper considers a decentralized and autonomous wireless network of low SWaP (size, weight, and power) fixed-wing UAVs (unmanned aerial vehicles) used for remote exploration and monitoring of targets in an inaccessible area lacking communication infrastructure. Here, the UAVs collaborate to find target(s) and use routing protocols to forward the sensed data of target(s) to an aerial base station (BS) in real-time through multihop communication, which can then transmit the data to a control center. However, the unpredictability of target locations and the highly dynamic nature of autonomous, decentralized UAV networks result in frequent route breaks or traffic disruptions. Traditional routing schemes cannot quickly adapt to dynamic UAV networks and can incur large control overhead and delays. In addition, their performance suffers from poor network connectivity in sparse networks with multiple objectives (exploration and monitoring of targets), which results in frequent route unavailability. To address these challenges, we propose two routing schemes: Pipe routing and TC-Pipe routing. Pipe routing is a mobility-, congestion-, and energy-aware scheme that discovers routes to the BS on-demand and proactively switches to alternate high-quality routes within a limited region around the routes (referred to as the “pipe”) when needed. TC-Pipe routing extends this approach by incorporating a decentralized topology control mechanism to help maintain robust connectivity in the pipe region around the routes, resulting in improved route stability and availability. The proposed schemes adopt a novel approach by integrating the topology control with routing protocol and mobility model, and rely only on local information in a distributed manner. Comprehensive evaluations under diverse network and traffic conditions—including UAV density and speed, number of targets, and fault tolerance—show that the proposed schemes improve throughput by reducing flow interruptions and packet drops caused by mobility, congestion, and node failures. At the same time, the impact on coverage performance (measured in terms of coverage and coverage fairness) is minimal, even with multiple targets. Additionally, the performance of both schemes degrades gracefully as the percentage of UAV failures in the network increases. Compared to schemes that use dedicated UAVs as relay nodes to establish a route to the BS when the UAV density is low, Pipe and TC-Pipe routing offer better coverage and connectivity trade-offs, with the TC-Pipe providing the best trade-off. Full article
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29 pages, 2118 KiB  
Article
Research on Value Co-Creation Evolution Mechanism of Cross-Border Cooperation in Intelligent Connected Vehicle Industry
by Jinhuan Tang, Yiming Chen, Dan Zhao and Shoufeng Ji
Systems 2025, 13(2), 121; https://doi.org/10.3390/systems13020121 - 13 Feb 2025
Abstract
With the continuous development of information and communication technology, “software-defined vehicle” has become the trend of the times. The intelligent connected vehicle (ICV) is becoming a new direction for the development of the automotive industry. Nevertheless, the absence of cooperative innovation in the [...] Read more.
With the continuous development of information and communication technology, “software-defined vehicle” has become the trend of the times. The intelligent connected vehicle (ICV) is becoming a new direction for the development of the automotive industry. Nevertheless, the absence of cooperative innovation in the ICV sector, the dispersal of industrial chain resources, and the absence of enduring and consistent cooperation pose significant obstacles to value co-creation. Therefore, this paper constructs a value co-creation evolutionary game model of the innovation ecosystem of the ICV industry with the automotive enterprise, an intelligent automotive solution provider and the government as players, and applies prospect theory to optimize the tripartite evolutionary game. The payment matrix is established, the expected revenue is analyzed for each player’s strategies, and the replication dynamic equation and evolutionary stability strategy are analyzed. Finally, the theoretical research is validated through numerical simulation. The aim is to promote value co-creation by analyzing the co-evolution mechanism of various stakeholder strategies in the ICV innovation ecosystem. The results show the following: (1) The best evolutionary stability strategy is the positive cross-border cooperation between the automotive enterprise and the intelligent automotive solution provider, while the government gradually does not provide subsidies. (2) The government’s subsidy support should be controlled within an appropriate range. If the subsidy is too great, the marginal effect of incentives will gradually weaken. (3) The players’ willingness to integrate across borders can be enhanced by a higher level of trust and resource complementarity between the automotive enterprise and intelligent automotive solution provider. Also, liquidated damages and opportunity loss can effectively prevent the occurrence of negative integration behaviors. (4) The greater the risk attitude coefficient and risk aversion coefficient of the automotive enterprise and intelligent automotive solution provider, the more conducive they are to the occurrence of positive integration behavior. Full article
(This article belongs to the Section Systems Practice in Social Science)
18 pages, 1028 KiB  
Article
Entropy and Stability in Blockchain Consensus Dynamics
by Aristidis G. Anagnostakis and Euripidis Glavas
Information 2025, 16(2), 138; https://doi.org/10.3390/info16020138 - 13 Feb 2025
Abstract
Every Blockchain architecture relies upon two major pillars: (a) the hash-based, block-binding mechanism and (b) the consensus-achievement mechanism. While the entropic behavior of (a) has been extensively studied in literature over the past decades, the same does not hold for (b). In this [...] Read more.
Every Blockchain architecture relies upon two major pillars: (a) the hash-based, block-binding mechanism and (b) the consensus-achievement mechanism. While the entropic behavior of (a) has been extensively studied in literature over the past decades, the same does not hold for (b). In this work, we explore the entropic behavior of the fully distributed Blockchain consensus mechanisms. We quantify the impact of witnessing as a consensus-achievement process under the perspectives of Shannon information entropy and Lyapunov stability. We demonstrate that Blockchain consensus, expressed as the complement of the collective disagreement in a system, is a Lyapunov function of the number of witnesses W. The more the witnessing in a system, the less the entropy of the system becomes, and it converges to more stable states. We prove that the entropy decline is steepest for low values of W. A new metric for the efficiency of the consensus process based on the Shannon information entropy is introduced, laying the foundations for future studies on Blockchain-based systems optimization. Full article
20 pages, 1117 KiB  
Article
FPGA Implementation of Image Encryption by Adopting New Shimizu–Morioka System-Based Chaos Synchronization
by Cheng-Hsiung Yang, Jian-De Lee, Lap-Mou Tam, Shih-Yu Li and Shyi-Chyi Cheng
Electronics 2025, 14(4), 740; https://doi.org/10.3390/electronics14040740 - 13 Feb 2025
Abstract
This study presents an innovative approach utilizing the new Shimizu–Morioka chaotic system. By integrating adaptive backstepping control with GYC partial region stability theory, we successfully achieve synchronization of a slave system with the proposed Shimizu–Morioka chaotic system. The architecture, encompassing the chaotic master [...] Read more.
This study presents an innovative approach utilizing the new Shimizu–Morioka chaotic system. By integrating adaptive backstepping control with GYC partial region stability theory, we successfully achieve synchronization of a slave system with the proposed Shimizu–Morioka chaotic system. The architecture, encompassing the chaotic master system, synchronized slave system, adaptive backstepping controllers, and parameter update laws, has been implemented on an FPGA platform. Comparative analysis demonstrates that the synchronization convergence times (e1, e2, e3, and e4) are significantly reduced compared to conventional adaptive backstepping control methods, exhibiting speed enhancements of approximately 3.42, 3.55, 5.89, and 9.23 times for e1, e2, e3, and e4, respectively. Furthermore, the synchronization results obtained from continuous-time, discrete-time systems, and FPGA implementations exhibit consistent outcomes, validating the effectiveness of the proposed model and controller. Leveraging this validated synchronization framework, chaotic synchronization and secure image encryption are successfully implemented on the FPGA platform. The chaotic signal circuits are meticulously designed and integrated into the FPGA to facilitate a robust image encryption algorithm. In this system, digital signals generated by the synchronized slave chaotic system are utilized for image decryption, while the master chaotic system’s digital signals are employed for encryption. This dual-system architecture highlights the efficacy of the chaotic synchronization method based on the novel Shimizu–Morioka system for practical applications in secure communication. Full article
21 pages, 28534 KiB  
Article
RACR-ShipDet: A Ship Orientation Detection Method Based on Rotation-Adaptive ConvNeXt and Enhanced RepBiFPAN
by Jiandan Zhong, Lingfeng Liu, Fei Song, Yingxiang Li and Yajuan Xue
Remote Sens. 2025, 17(4), 643; https://doi.org/10.3390/rs17040643 - 13 Feb 2025
Abstract
Ship orientation detection is essential for maritime navigation, traffic monitoring, and defense, yet existing methods face challenges with rotational invariance in large-angle scenarios, difficulties in multi-scale feature fusion, and the limitations of traditional IoU when detecting oriented objects and predicting objects’ orientation. In [...] Read more.
Ship orientation detection is essential for maritime navigation, traffic monitoring, and defense, yet existing methods face challenges with rotational invariance in large-angle scenarios, difficulties in multi-scale feature fusion, and the limitations of traditional IoU when detecting oriented objects and predicting objects’ orientation. In this article, we propose a novel ship orientation detection (RACR-ShipDet) network based on rotation-adaptive ConvNeXt and Enhanced RepBiFPAN in remote sensing images. To equip the model with rotational invariance, ConvNeXt is first improved so that it can dynamically adjust the rotation angle and convolution kernel through adaptive rotation convolution, namely, ARRConv, forming a new architecture called RotConvNeXt. Subsequently, the RepBiFPAN, enhanced with the Weighted Feature Aggregation module, is employed to prioritize informative features by dynamically assigning adaptive weights, effectively reducing the influence of redundant or irrelevant features and improving feature representation. Moreover, a more stable version of KFIoU is proposed, named SCKFIoU, which improves the accuracy and stability of overlap calculation by introducing a small perturbation term and utilizing Cholesky decomposition for efficient matrix inversion and determinant calculation. Evaluations using the DOTA-ORShip dataset demonstrate that RACR-ShipDet outperforms current state-of-the-art models, achieving an mAP of 95.3%, representing an improvement of 5.3% over PSC (90.0%) and of 1.9% over HDDet (93.4%). Furthermore, it demonstrates a superior orientation accuracy of 96.9%, exceeding HDDet by a margin of 5.0%, establishing itself as a robust solution for ship orientation detection in complex environments. Full article
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19 pages, 27022 KiB  
Article
A Highly Stabilized Current Source Topology with Slope Compensation for a High-Power Microwave Guiding Coil
by Dandi Zhang, Hongfa Ding, Zhou He, Wentao Zhou and Ziqi Zhang
Electronics 2025, 14(4), 739; https://doi.org/10.3390/electronics14040739 - 13 Feb 2025
Abstract
For the waveguide coil in a High-Power Microwave (HPM) source, a strong repetitive Flat-top Pulsed Magnetic Field (FTPMF) is needed, which requires the power supply system to generate a high load current (3∼5 kA) with high stability (<1000 ppm) and a long pulse-width [...] Read more.
For the waveguide coil in a High-Power Microwave (HPM) source, a strong repetitive Flat-top Pulsed Magnetic Field (FTPMF) is needed, which requires the power supply system to generate a high load current (3∼5 kA) with high stability (<1000 ppm) and a long pulse-width (15∼20 ms). To achieve this, this article proposes a novel topology which includes a capacitor bank as the main power supply to guarantee a long pulse-width, combined with an active current compensator to regulate the load current precisely. A PI control scheme with slope compensation is used to solve the current fluctuation caused by capacitor switching. The novel topology also features a fast rising and falling time, thus it is suitable for repetitive working applications. The parameters of the topology are calculated by analysis to guarantee the working condition of a 45 GHz HPM source, and the operating principle of this topology is verified through low-power-scale experiments. Full article
(This article belongs to the Special Issue Advances in Pulsed-Power and High-Power Electronics)
22 pages, 5029 KiB  
Article
Long-Term Spatiotemporal Evolution Characteristics and Driving Force Analysis of Landscape Stability in the Forest–Grassland Ecotone of the Greater Khingan Mountains, Inner Mongolia, China
by Qingchi Han, Jinzhuo Wu and Wenshu Lin
Land 2025, 14(2), 396; https://doi.org/10.3390/land14020396 - 13 Feb 2025
Abstract
Forest–grassland ecotones refer to the transitional area between forest and grassland ecosystems. Previous studies mainly focus on environmentally sensitive features and landscape risk pressures caused by edge effects, ignoring the landscape restoration and stability changes brought about by high species diversity. In this [...] Read more.
Forest–grassland ecotones refer to the transitional area between forest and grassland ecosystems. Previous studies mainly focus on environmentally sensitive features and landscape risk pressures caused by edge effects, ignoring the landscape restoration and stability changes brought about by high species diversity. In this study, we calculated the landscape stability in the forest–grassland ecotone of the Greater Khingan Mountains in Inner Mongolia, China from 1990 to 2020, analyzed the changing trends and spatial migration dynamics of the landscape stability, and revealed the potential driving factors and spatial heterogeneity of dominant driving factors for the changes in landscape stability. The results indicated that the dominant landscapes in the study area changed from forests and grasslands in 1990 to forest-dominated landscapes in 2020, and the landscape stability gradually improved from a lower level to a higher level. The stability gradually expanded from the center to the northeast and southwest edges, exhibiting a ribbon sprawl pattern, and the stable center gradually moved to the northeast from 1990 to 2020. Climate factors were the main driving forces affecting the changes in landscape stability in the study area. Different dominant driving factors showed various spatial heterogeneity over time. In the northern part of the forest–grassland ecotone, precipitation, and NDVI had positive correlations with landscape stability, while the opposite was true in the south. In addition, the area of landscape stability in the south that was positively correlated with temperature and NDVI gradually expanded over time. This study analyzed the unique ecological advantages of the forest–grassland ecotones from the perspective of landscape stability changes, which will be facilitated in the ecological assessments and restoration of the forest–grassland ecotones. Full article
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27 pages, 4292 KiB  
Review
Superabsorbent Polymers: Innovations in Ecology, Environmental, and Diverse Applications
by Qingya Niu, Jiayin Xie, Jiayan Li, Zaixu An, Huijie Xiao, Xiaoyuan Zhang, Zhiqiang Su and Zhichao Wang
Materials 2025, 18(4), 823; https://doi.org/10.3390/ma18040823 - 13 Feb 2025
Abstract
Significant progress has been achieved in the development of superabsorbent polymers (SAPs), focusing on enhancing their performance and expanding their applications. Efforts are particularly directed at increasing water absorbency while promoting environmental sustainability. Biodegradable materials such as starch and potassium humate have been [...] Read more.
Significant progress has been achieved in the development of superabsorbent polymers (SAPs), focusing on enhancing their performance and expanding their applications. Efforts are particularly directed at increasing water absorbency while promoting environmental sustainability. Biodegradable materials such as starch and potassium humate have been successfully integrated with SAPs for desert greening, improving water retention, salt resistance, and seedling survival. The inclusion of nutrient-rich organic-inorganic composites further enhances the durability, efficiency, and recyclability of SAPs. In drought mitigation, polymeric absorbent resins such as polyacrylamide and starch-grafted acrylates have shown efficacy in ameliorating soil conditions and fostering plant growth. In arid environments, agents enriched with humic acid and bentonite contribute to improved soil aeration and water retention, creating optimal conditions for plant establishment. Additionally, the adoption of innovative waste management solutions has led to the production of amphiphilic SAPs from residual sludge, effectively addressing soil nutrient deficiencies and environmental pollution. In the food industry, SAPs containing protease, tea polyphenols, and chitosan exhibit potential for enhancing the stability and quality of seafood products. These advancements highlight the growing relevance of structural optimization approaches in SAP development across diverse applications and underline the importance of continued innovation in these fields. As novel materials emerge and environmental challenges intensify, the potential applications of SAPs are anticipated to expand significantly. Full article
(This article belongs to the Special Issue Construction and Applications in Functional Polymers)
26 pages, 1038 KiB  
Article
Deep Learning Artificial Neural Network for Pricing Multi-Asset European Options
by Zhiqiang Zhou, Hongying Wu, Yuezhang Li, Caijuan Kang and You Wu
Mathematics 2025, 13(4), 617; https://doi.org/10.3390/math13040617 - 13 Feb 2025
Abstract
This paper studies a p-layers deep learning artificial neural network (DLANN) for European multi-asset options. Firstly, a p-layers DLANN is constructed with undetermined weights and bias. Secondly, according to the terminal values of the partial differential equation (PDE) and the points [...] Read more.
This paper studies a p-layers deep learning artificial neural network (DLANN) for European multi-asset options. Firstly, a p-layers DLANN is constructed with undetermined weights and bias. Secondly, according to the terminal values of the partial differential equation (PDE) and the points that satisfy the PDE of multi-asset options, some discrete data are fed into the p-layers DLANN. Thirdly, using the least square error as the objective function, the weights and bias of the DLANN are trained well. In order to optimize the objective function, the partial derivatives for the weights and bias of DLANN are carefully derived. Moreover, to improve the computational efficiency, a time-segment DLANN is proposed. Numerical examples are presented to confirm the accuracy, efficiency, and stability of the proposed p-layers DLANN. Computational examples show that the DLANN’s relative error is less than 0.5% for different numbers of assets d=1,2,3,4. In the future, the p-layers DLANN can be extended into American options, Asian options, Lookback options, and so on. Full article
(This article belongs to the Special Issue Advances in Partial Differential Equations: Methods and Applications)
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22 pages, 673 KiB  
Article
Energy Efficacy Enhancement in a Reactive Couple-Stress Fluid Induced by Electrokinetics and Pressure Gradient with Variable Fluid Properties
by Peace O. Banjo, Ramoshweu S. Lebelo, Samuel O. Adesanya and Emmanuel I. Unuabonah
Mathematics 2025, 13(4), 615; https://doi.org/10.3390/math13040615 - 13 Feb 2025
Abstract
This study presents a mathematical analysis of the collective effect of chemical reactions, variable fluid properties, and thermal stability of a hydromagnetic couple-stress fluid flowing through a microchannel driven by electro-osmosis and a pressure gradient. The viscosity of the biofluid is assumed to [...] Read more.
This study presents a mathematical analysis of the collective effect of chemical reactions, variable fluid properties, and thermal stability of a hydromagnetic couple-stress fluid flowing through a microchannel driven by electro-osmosis and a pressure gradient. The viscosity of the biofluid is assumed to depend on the temperature, while the electrical conductivity is assumed to be a linear function of the drift velocity. The governing equations are derived non-dimensionalized, and numerical solutions are obtained using the spectral Chebyshev collocation method. The numerical solution is validated using the shooting Runge–Kutta method. The effects of varying the parameters on the thermal stability, temperature, velocity, and entropy profiles are discussed with adequate interpretations using tables and graphs. The results reveal that the chemical reactions and viscosity parameter increase the fluid temperature, while the Hartmann number decreases the temperature and increases the flow velocity and entropy generation. It was also observed that the chemical reactions and viscosity parameter increased the entropy at the channel walls, while the Hartmann number decreased the entropy at the core center of the channel. This study has tremendous empirical significance, including but not limited to biophysical applications of devices, engineering applications such as control systems, and thermo-fluidic transport. Full article
(This article belongs to the Special Issue Advanced Computational Methods for Fluid Dynamics and Applications)
13 pages, 249 KiB  
Article
On the Three-Dimensional Shape of a Crystal
by Emanuel Indrei and Aram Karakhanyan
Mathematics 2025, 13(4), 614; https://doi.org/10.3390/math13040614 - 13 Feb 2025
Abstract
The purpose of this paper is to investigate the Almgren problem in R3 under generic conditions on the potential and tension functions which define the free energy. This problem appears in classical thermodynamics when one seeks to understand whether minimizing the free [...] Read more.
The purpose of this paper is to investigate the Almgren problem in R3 under generic conditions on the potential and tension functions which define the free energy. This problem appears in classical thermodynamics when one seeks to understand whether minimizing the free energy with convex potential in the class of sets of finite perimeter under a mass constraint generates a convex minimizer representing a crystal. Our new idea in proving a three-dimensional convexity theorem is to utilize convexity and a stability theorem when the mass is small, as well as a first-variation partial differential equation along with a new maximum principle approach. Full article
(This article belongs to the Section E4: Mathematical Physics)
22 pages, 934 KiB  
Article
Improvement in Performance Characteristics of Bitumen and Bituminous Mixtures by Means of Polyvinyl Acetate
by Yalçın Oğuz Hetemoğlu, Mustafa Kürşat Çubuk and Metin Gürü
Constr. Mater. 2025, 5(1), 9; https://doi.org/10.3390/constrmater5010009 - 13 Feb 2025
Abstract
This paper examines the improvement in the performance characteristics and the rheological properties of modified bitumen through the addition of the thermoplastic polymer polyvinyl acetate (PVA). PVA is a synthetic polymer derived from the polymerization of the vinyl acetate. The effect of PVA [...] Read more.
This paper examines the improvement in the performance characteristics and the rheological properties of modified bitumen through the addition of the thermoplastic polymer polyvinyl acetate (PVA). PVA is a synthetic polymer derived from the polymerization of the vinyl acetate. The effect of PVA on bitumen and bituminous mixtures was investigated through the conventional (penetration, softening point, force-ductility, elastic recovery, Marshall and Nicholson stripping tests) and Superpave (rotational viscosity (RV), rolling thin film oven (RTFOT), pressure aging vessel (PAV), dynamic shear rheometer (DSR) and beam bending rheometer (BBR)) tests. PVA was added to bitumen at rates of 2%, 4%, 6% and 8% by mass. Based on the bitumen test results, a PVA rate of 6% was selected for the mixture tests. The modification process was carried out at relatively low temperature (150 °C) and mixing time (20 min) based on various trials, considering the short-term aging of the bitumen. With PVA modification, the penetration value of the bitumen decreased while the softening point increased. As a result, the calculated penetration index (PI) increased and the thermal sensitivity of the bitumen decreased. Significant improvements were detected in elastic recovery and force-ductility tests. Additionally, PVA improved the resistance of asphalt to settling and cracking. Similar results were observed in the DSR and BBR tests. Furthermore, the stripping resistance increased and the stability value improved significantly in the mixture tests. Full article
(This article belongs to the Special Issue Innovative Materials and Technologies for Road Pavements)
20 pages, 2307 KiB  
Article
Improved Enzymatic Properties of Chitosanase CsnMY002 from Bacillus subtilis via Computational Design
by Jie Xie, Jingwei Liu, Si Wang and Ganggang Wang
Int. J. Mol. Sci. 2025, 26(4), 1588; https://doi.org/10.3390/ijms26041588 - 13 Feb 2025
Abstract
Chitooligosaccharides (COSs) are a class of functional carbohydrates with significant application prospects in food and medicine. Chitosanase CsnMY002 from the GH46 family has been used to prepare COS with controlled degrees of polymerization. To enhance the industrial applicability of CsnMY002, molecular dynamics (MD) [...] Read more.
Chitooligosaccharides (COSs) are a class of functional carbohydrates with significant application prospects in food and medicine. Chitosanase CsnMY002 from the GH46 family has been used to prepare COS with controlled degrees of polymerization. To enhance the industrial applicability of CsnMY002, molecular dynamics (MD) simulations were applied to investigate the structure–property relationship. Guided by the simulation results, the beneficial mutants were screened through a synergistic strategy using a residue-folding free energy calculation and consensus sequence analysis. Iterative combinations constructed the mutant Mut6 (A49G/K70A/S84A/N89G/D199R/N221G) with significantly improved thermal stability, which had a half-life (t1/2 value) at 55 °C and 75 °C that was 1.80 and 1.62 times higher than that of the wild type, respectively. A highly active mutant, Mut2, was created, exhibiting a 1.52 times catalytic efficiency of the wild type. An MD simulation analysis of the mutants suggested that the improved enzymatic properties were highly correlated with changes in the dynamic behaviours of the enzyme structure. This study generated more suitable CsnMY002 variants for COS production and provided a comprehensive strategy for the optimization of other industrial enzymes with application potential. Full article
(This article belongs to the Special Issue Microbial Enzymes for Biotechnological Applications: 2nd Edition)
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28 pages, 885 KiB  
Article
Global Optimal Automatic Generation Control of a Multimachine Power System Using Hybrid NLMPC and Data-Driven Methods
by Ahmed Khamees and Hüseyin Altınkaya
Appl. Sci. 2025, 15(4), 1956; https://doi.org/10.3390/app15041956 - 13 Feb 2025
Abstract
Real-world power systems face challenges from demand fluctuations, system constraints, communication delays, and unmeasurable disturbances. This paper presents a real-time hybrid approach integrating Nonlinear Model Predictive Control (NLMPC) and data-driven methods for automatic generation control (AGC) of synchronous generators, particularly under cyber-physical attacks. [...] Read more.
Real-world power systems face challenges from demand fluctuations, system constraints, communication delays, and unmeasurable disturbances. This paper presents a real-time hybrid approach integrating Nonlinear Model Predictive Control (NLMPC) and data-driven methods for automatic generation control (AGC) of synchronous generators, particularly under cyber-physical attacks. Unlike previous studies, this work considers both technical and economic aspects of power system management. A key innovation is the incorporation of a detailed thermo-mechanical model of turbine and governor dynamics, enabling optimized control and effective management of power oscillations. The proposed NLMPC-based AGC strategy addresses governor saturation and generation rate constraints, ensuring stability. Extensive simulations in MATLAB/Simulink, including IEEE 11-bus and 9-bus test systems, validate the controller’s effectiveness in enhancing power system performance under various challenging conditions. Full article
(This article belongs to the Topic Electronic Communications, IOT and Big Data, 2nd Volume)
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