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42 pages, 1287 KiB  
Review
A Comprehensive Review of the Latest Approaches to Managing Hypercholesterolemia: A Comparative Analysis of Conventional and Novel Treatments: Part II
by Narcisa Jianu, Ema-Teodora Nițu, Cristina Merlan, Adina Nour, Simona Buda, Maria Suciu, Silvia Ana Luca, Laura Sbârcea, Minodora Andor and Valentina Buda
Pharmaceuticals 2025, 18(8), 1150; https://doi.org/10.3390/ph18081150 (registering DOI) - 1 Aug 2025
Abstract
Cardiovascular disease (CVD) remains the leading cause of mortality worldwide, with hypercholesterolemia identified as a major, but modifiable risk factor. This review serves as the second part of a comprehensive analysis of dyslipidemia management. The first installment laid the groundwork by detailing the [...] Read more.
Cardiovascular disease (CVD) remains the leading cause of mortality worldwide, with hypercholesterolemia identified as a major, but modifiable risk factor. This review serves as the second part of a comprehensive analysis of dyslipidemia management. The first installment laid the groundwork by detailing the key pathophysiological mechanisms of lipid metabolism, the development of atherosclerosis, major complications of hyperlipidemia, and the importance of cardiovascular risk assessment in therapeutic decision-making. It also examined non-pharmacological interventions and conventional therapies, with a detailed focus on statins and ezetimibe. Building upon that foundation, the present article focuses exclusively on emerging pharmacological therapies designed to overcome limitations of standard treatment. It explores the mechanisms, clinical applications, safety profiles, and pharmacogenetic aspects of novel agents such as proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors (alirocumab, evolocumab), small interfering RNA (siRNA) therapy (inclisiran), adenosine triphosphate–citrate lyase (ACL) inhibitor (bempedoic acid), microsomal triglyceride transfer protein (MTP) inhibitor (lomitapide), and angiopoietin-like protein 3 (ANGPTL3) inhibitor (evinacumab). These agents offer targeted strategies for patients with high residual cardiovascular risk, familial hypercholesterolemia (FH), or statin intolerance. By integrating the latest advances in precision medicine, this review underscores the expanding therapeutic landscape in dyslipidemia management and the evolving potential for individualized care. Full article
(This article belongs to the Special Issue Pharmacotherapy of Dyslipidemias, 2nd Edition)
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15 pages, 1515 KiB  
Article
Ontology-Based Data Pipeline for Semantic Reaction Classification and Research Data Management
by Hendrik Borgelt, Frederick Gabriel Kitel and Norbert Kockmann
Computers 2025, 14(8), 311; https://doi.org/10.3390/computers14080311 (registering DOI) - 1 Aug 2025
Viewed by 100
Abstract
Catalysis research is complex and interdisciplinary, involving diverse physical effects and challenging data practices. Research data often captures only selected aspects, such as specific reactants and products, limiting its utility for machine learning and the implementation of FAIR (Findable, Accessible, Interoperable, Reusable) workflows. [...] Read more.
Catalysis research is complex and interdisciplinary, involving diverse physical effects and challenging data practices. Research data often captures only selected aspects, such as specific reactants and products, limiting its utility for machine learning and the implementation of FAIR (Findable, Accessible, Interoperable, Reusable) workflows. To improve this, semantic structuring through ontologies is essential. This work extends the established ontologies by refining logical relations and integrating semantic tools such as the Web Ontology Language or the Shape Constraint Language. It incorporates application programming interfaces from chemical databases, such as the Kyoto Encyclopedia of Genes and Genomes and the National Institute of Health’s PubChem database, and builds upon established ontologies. A key innovation lies in automatically decomposing chemical substances through database entries and chemical identifier representations to identify functional groups, enabling more generalized reaction classification. Using new semantic functionality, functional groups are flexibly addressed, improving the classification of reactions such as saponification and ester cleavage with simultaneous oxidation. A graphical interface (GUI) supports user interaction with the knowledge graph, enabling ontological reasoning and querying. This approach demonstrates improved specificity of the newly established ontology over its predecessors and offers a more user-friendly interface for engaging with structured chemical knowledge. Future work will focus on expanding ontology coverage to support a wider range of reactions in catalysis research. Full article
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24 pages, 4753 KiB  
Article
A Secure Satellite Transmission Technique via Directional Variable Polarization Modulation with MP-WFRFT
by Zhiyu Hao, Zukun Lu, Xiangjun Li, Xiaoyu Zhao, Zongnan Li and Xiaohui Liu
Aerospace 2025, 12(8), 690; https://doi.org/10.3390/aerospace12080690 (registering DOI) - 31 Jul 2025
Viewed by 131
Abstract
Satellite communications are pivotal to global Internet access, connectivity, and the advancement of information warfare. Despite these importance, the open nature of satellite channels makes them vulnerable to eavesdropping, making the enhancement of interception resistance in satellite communications a critical issue in both [...] Read more.
Satellite communications are pivotal to global Internet access, connectivity, and the advancement of information warfare. Despite these importance, the open nature of satellite channels makes them vulnerable to eavesdropping, making the enhancement of interception resistance in satellite communications a critical issue in both academic and industrial circles. Within the realm of satellite communications, polarization modulation and quadrature techniques are essential for information transmission and interference suppression. To boost electromagnetic countermeasures in complex battlefield scenarios, this paper integrates multi-parameter weighted-type fractional Fourier transform (MP-WFRFT) with directional modulation (DM) algorithms, building upon polarization techniques. Initially, the operational mechanisms of the polarization-amplitude-phase modulation (PAPM), MP-WFRFT, and DM algorithms are elucidated. Secondly, it introduces a novel variable polarization-amplitude-phase modulation (VPAPM) scheme that integrates variable polarization with amplitude-phase modulation. Subsequently, leveraging the VPAPM modulation scheme, an exploration of the anti-interception capabilities of MP-WFRFT through parameter adjustment is presented. Rooted in an in-depth analysis of simulation data, the anti-scanning capabilities of MP-WFRFT are assessed in terms of scale vectors in the horizontal and vertical direction. Finally, exploiting the potential of the robust anti-scanning capabilities of MP-WFRFT and the directional property of antenna arrays in DM, the paper proposes a secure transmission technique employing directional variable polarization modulation with MP-WFRFT. The performance simulation analysis demonstrates that the integration of MP-WFRFT and DM significantly outperforms individual secure transmission methods, improving anti-interception performance by at least an order of magnitude at signal-to-noise ratios above 10 dB. Consequently, this approach exhibits considerable potential and engineering significance for its application within satellite communication systems. Full article
(This article belongs to the Section Astronautics & Space Science)
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19 pages, 8583 KiB  
Article
Development and Immunogenic Evaluation of a Recombinant Vesicular Stomatitis Virus Expressing Nipah Virus F and G Glycoproteins
by Huijuan Guo, Renqiang Liu, Dan Pan, Yijing Dang, Shuhuai Meng, Dan Shan, Xijun Wang, Jinying Ge, Zhigao Bu and Zhiyuan Wen
Viruses 2025, 17(8), 1070; https://doi.org/10.3390/v17081070 - 31 Jul 2025
Viewed by 135
Abstract
Nipah virus (NiV) is a highly pathogenic bat-borne zoonotic pathogen that poses a significant threat to human and animal health, with fatality rates exceeding 70% in some outbreaks. Despite its significant public health impact, there are currently no licensed vaccines or specific therapeutics [...] Read more.
Nipah virus (NiV) is a highly pathogenic bat-borne zoonotic pathogen that poses a significant threat to human and animal health, with fatality rates exceeding 70% in some outbreaks. Despite its significant public health impact, there are currently no licensed vaccines or specific therapeutics available. Various virological tools—such as reverse genetics systems, replicon particles, VSV-based pseudoviruses, and recombinant Cedar virus chimeras—have been widely used to study the molecular mechanisms of NiV and to support vaccine development. Building upon these platforms, we developed a replication-competent recombinant vesicular stomatitis virus (rVSVΔG-eGFP-NiVBD F/G) expressing NiV attachment (G) and fusion (F) glycoproteins. This recombinant virus serves as a valuable tool for investigating NiV entry mechanisms, cellular tropism, and immunogenicity. The virus was generated by replacing the VSV G protein with NiV F/G through reverse genetics, and protein incorporation was confirmed via immunofluorescence and electron microscopy. In vitro, the virus exhibited robust replication, characteristic cell tropism, and high viral titers in multiple cell lines. Neutralization assays showed that monoclonal antibodies HENV-26 and HENV-32 effectively neutralized the recombinant virus. Furthermore, immunization of golden hamsters with inactivated rVSVΔG-eGFP-NiVBD F/G induced potent neutralizing antibody responses, demonstrating its robust immunogenicity. These findings highlight rVSVΔG-eGFP-NiVBD F/G as an effective platform for NiV research and vaccine development. Full article
(This article belongs to the Section Animal Viruses)
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19 pages, 4397 KiB  
Article
Thermal History-Dependent Deformation of Polycarbonate: Experimental and Modeling Insights
by Maoyuan Li, Haitao Wang, Guancheng Shen, Tianlun Huang and Yun Zhang
Polymers 2025, 17(15), 2096; https://doi.org/10.3390/polym17152096 - 30 Jul 2025
Viewed by 211
Abstract
The deformation behavior of polymers is influenced not only by service conditions such as temperature and the strain rate but also significantly by the formation process. However, existing simulation frameworks typically treat injection molding and the in-service mechanical response separately, making it difficult [...] Read more.
The deformation behavior of polymers is influenced not only by service conditions such as temperature and the strain rate but also significantly by the formation process. However, existing simulation frameworks typically treat injection molding and the in-service mechanical response separately, making it difficult to capture the impact of the thermal history on large deformation behavior. In this study, the deformation behavior of injection-molded polycarbonate (PC) was investigated by accounting for its thermal history during formation, achieved through combined experimental characterization and constitutive modeling. PC specimens were prepared via injection molding followed by annealing at different molding/annealing temperatures and durations. Uniaxial tensile tests were conducted using a Zwick universal testing machine at strain rates of 10−3–10−1 s−1 and temperatures ranging from 293 K to 353 K to obtain stress–strain curves. The effects of the strain rate, testing temperature, and annealing conditions were thoroughly examined. Building upon a previously proposed phenomenological model, a new constitutive framework incorporating thermal history effects during formation was developed to characterize the large deformation behavior of PC. This model was implemented in ABAQUS/Explicit using a user-defined material subroutine. Predicted stress–strain curves exhibit excellent agreement with the experimental data, accurately reproducing elastic behavior, yield phenomena, and strain-softening and strain-hardening stages. Full article
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16 pages, 3379 KiB  
Article
Research on Electric Vehicle Differential System Based on Vehicle State Parameter Estimation
by Huiqin Sun and Honghui Wang
Vehicles 2025, 7(3), 80; https://doi.org/10.3390/vehicles7030080 - 30 Jul 2025
Viewed by 162
Abstract
To improve the stability and safety of electric vehicles during medium-to-high-speed cornering, this paper investigates torque differential control for dual rear-wheel hub motor drive systems, extending beyond traditional speed control based on the Ackermann steering model. A nonlinear three-degree-of-freedom vehicle dynamics model incorporating [...] Read more.
To improve the stability and safety of electric vehicles during medium-to-high-speed cornering, this paper investigates torque differential control for dual rear-wheel hub motor drive systems, extending beyond traditional speed control based on the Ackermann steering model. A nonlinear three-degree-of-freedom vehicle dynamics model incorporating the Dugoff tire model was established. By introducing the maximum correntropy criterion, an unscented Kalman filter was developed to estimate longitudinal velocity, sideslip angle at the center of mass, and yaw rate. Building upon the speed differential control achieved through Ackermann steering model-based rear-wheel speed calculation, improvements were made to the conventional exponential reaching law, while a novel switching function was proposed to formulate a new sliding mode controller for computing an additional yaw moment to realize torque differential control. Finally, simulations conducted on the Carsim/Simulink platform demonstrated that the maximum correntropy criterion unscented Kalman filter effectively improves estimation accuracy, achieving at least a 22.00% reduction in RMSE metrics compared to conventional unscented Kalman filter. With torque control exhibiting higher vehicle stability than speed control, the RMSE values of yaw rate and sideslip angle at the center of mass are reduced by at least 20.00% and 4.55%, respectively, enabling stable operation during medium-to-high-speed cornering conditions. Full article
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18 pages, 8520 KiB  
Article
Cross-Layer Controller Tasking Scheme Using Deep Graph Learning for Edge-Controlled Industrial Internet of Things (IIoT)
by Abdullah Mohammed Alharthi, Fahad S. Altuwaijri, Mohammed Alsaadi, Mourad Elloumi and Ali A. M. Al-Kubati
Future Internet 2025, 17(8), 344; https://doi.org/10.3390/fi17080344 - 30 Jul 2025
Viewed by 98
Abstract
Edge computing (EC) plays a critical role in advancing the next-generation Industrial Internet of Things (IIoT) by enhancing production, maintenance, and operational outcomes across heterogeneous network boundaries. This study builds upon EC intelligence and integrates graph-based learning to propose a Cross-Layer Controller Tasking [...] Read more.
Edge computing (EC) plays a critical role in advancing the next-generation Industrial Internet of Things (IIoT) by enhancing production, maintenance, and operational outcomes across heterogeneous network boundaries. This study builds upon EC intelligence and integrates graph-based learning to propose a Cross-Layer Controller Tasking Scheme (CLCTS). The scheme operates through two primary phases: task grouping assignment and cross-layer control. In the first phase, controller nodes executing similar tasks are grouped based on task timing to achieve monotonic and synchronized completions. The second phase governs controller re-tasking both within and across these groups. Graph structures connect the groups to facilitate concurrent tasking and completion. A learning model is trained on inverse outcomes from the first phase to mitigate task acceptance errors (TAEs), while the second phase focuses on task migration learning to reduce task prolongation. Edge nodes interlink the groups and synchronize tasking, migration, and re-tasking operations across IIoT layers within unified completion periods. Departing from simulation-based approaches, this study presents a fully implemented framework that combines learning-driven scheduling with coordinated cross-layer control. The proposed CLCTS achieves an 8.67% reduction in overhead, a 7.36% decrease in task processing time, and a 17.41% reduction in TAEs while enhancing the completion ratio by 13.19% under maximum edge node deployment. Full article
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19 pages, 4756 KiB  
Article
Quasi-3D Mechanistic Model for Predicting Eye Drop Distribution in the Human Tear Film
by Harsha T. Garimella, Carly Norris, Carrie German, Andrzej Przekwas, Ross Walenga, Andrew Babiskin and Ming-Liang Tan
Bioengineering 2025, 12(8), 825; https://doi.org/10.3390/bioengineering12080825 (registering DOI) - 30 Jul 2025
Viewed by 131
Abstract
Topical drug administration is a common method of delivering medications to the eye to treat various ocular conditions, including glaucoma, dry eye, and inflammation. Drug efficacy following topical administration, including the drug’s distribution within the eye, absorption and elimination rates, and physiological responses [...] Read more.
Topical drug administration is a common method of delivering medications to the eye to treat various ocular conditions, including glaucoma, dry eye, and inflammation. Drug efficacy following topical administration, including the drug’s distribution within the eye, absorption and elimination rates, and physiological responses can be predicted using physiologically based pharmacokinetic (PBPK) modeling. High-resolution computational models of the eye are desirable to improve simulations of drug delivery; however, these approaches can have long run times. In this study, a fast-running computational quasi-3D (Q3D) model of the human tear film was developed to account for absorption, blinking, drainage, and evaporation. Visualization of blinking mechanics and flow distributions throughout the tear film were enabled using this Q3D approach. Average drug absorption throughout the tear film subregions was quantified using a high-resolution compartment model based on a system of ordinary differential equations (ODEs). Simulations were validated by comparing them with experimental data from topical administration of 0.1% dexamethasone suspension in the tear film (R2 = 0.76, RMSE = 8.7, AARD = 28.8%). Overall, the Q3D tear film model accounts for critical mechanistic factors (e.g., blinking and drainage) not previously included in fast-running models. Further, this work demonstrated methods toward improved computational efficiency, where central processing unit (CPU) time was decreased while maintaining accuracy. Building upon this work, this Q3D approach applied to the tear film will allow for more seamless integration into full-body models, which will be an extremely valuable tool in the development of treatments for ocular conditions. Full article
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27 pages, 378 KiB  
Article
Weighted Fractional Sobolev Spaces on Timescales with Applications to Weighted Fractional p-Laplacian Systems
by Qibing Tan, Jianwen Zhou and Yanning Wang
Fractal Fract. 2025, 9(8), 500; https://doi.org/10.3390/fractalfract9080500 - 30 Jul 2025
Viewed by 116
Abstract
The primary objective of this work is to develop a comprehensive theory of weighted fractional Sobolev spaces within the framework of timescales. To this end, we first introduce a novel class of weighted fractional operators and rigorously define associated weighted integrable spaces on [...] Read more.
The primary objective of this work is to develop a comprehensive theory of weighted fractional Sobolev spaces within the framework of timescales. To this end, we first introduce a novel class of weighted fractional operators and rigorously define associated weighted integrable spaces on timescales, generalising classical notions to this non-uniform temporal domain. Building upon these foundations, we systematically investigate the fundamental functional-analytic properties of the resulting Sobolev spaces. Specifically, we establish their completeness under appropriate norms, prove reflexivity under appropriate duality pairings, and demonstrate separability under mild conditions on the weight functions. As a pivotal application of our theoretical framework, we derive two robust existence theorems for solutions to the proposed model. These results not only extend classical partial differential equation theory to timescales but also provide a versatile tool for analysing dynamic systems with heterogeneous temporal domains. Full article
17 pages, 1207 KiB  
Article
Assessing Critical Risk Factors to Sustainable Housing in Urban Areas: Based on the NK-SNA Model
by Guangyu Sun and Hui Zeng
Sustainability 2025, 17(15), 6918; https://doi.org/10.3390/su17156918 - 30 Jul 2025
Viewed by 178
Abstract
Housing sustainability is a cornerstone element of sustainable economic and social development. This is particularly true for China, where high-rise residential buildings are the primary form of housing. In recent years, China has experienced frequent housing-related accidents, resulting in a significant loss of [...] Read more.
Housing sustainability is a cornerstone element of sustainable economic and social development. This is particularly true for China, where high-rise residential buildings are the primary form of housing. In recent years, China has experienced frequent housing-related accidents, resulting in a significant loss of life and property damage. This study aims to identify the key factors influencing housing sustainability and provide a basis for the prevention and control of housing-related safety risks. This study has developed a housing sustainability evaluation indicator system comprising three primary indicators and 16 secondary indicators. This system is based on an analysis of the causes of over 500 typical housing accidents that occurred in China over the past 10 years, employing research methods such as literature reviews and expert consultations, and drawing on the analytical frameworks of risk management theory and system safety theory. Subsequently, the NK-SNA model, which significantly outperforms traditional models in terms of adaptive learning and optimization, as well as the explicit modeling of complex nonlinear relationships, was used to identify the key risk factors affecting housing sustainability. The empirical results indicate that the risk coupling value is correlated with the number of risk coupling factors; the greater the number of risk coupling factors, the larger the coupling value. Human misconduct is prone to forming two-factor risk coupling with housing, and the physical risk factors are prone to coupling with other factors. The environmental factors easily trigger ‘physical–environmental’ two-factor risk coupling. The key factors influencing housing sustainability are poor supervision, building facilities, the main structure, the housing height, foundation settlement, and natural disasters. On this basis, recommendations are made to make full use of modern information technologies such as the Internet of Things, big data, and artificial intelligence to strengthen the supervision of housing safety and avoid multi-factor coupling, and to improve upon early warnings of natural disasters and the design of emergency response programs to control the coupling between physical and environmental factors. Full article
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18 pages, 2414 KiB  
Article
Deep Deliberation to Enhance Analysis of Complex Governance Systems: Reflecting on the Great Barrier Reef Experience
by Karen Vella, Allan Dale, Margaret Gooch, Diletta Calibeo, Mark Limb, Rachel Eberhard, Hurriyet Babacan, Jennifer McHugh and Umberto Baresi
Sustainability 2025, 17(15), 6911; https://doi.org/10.3390/su17156911 - 30 Jul 2025
Viewed by 363
Abstract
Deliberative approaches to governance systems analysis and improvement are rare. Australia’s Great Barrier Reef (GBR) provides the context to describe an innovative approach that combines reflexive and interactive engagement processes to (a) develop and design a framework to assess the GBR’s complex governance [...] Read more.
Deliberative approaches to governance systems analysis and improvement are rare. Australia’s Great Barrier Reef (GBR) provides the context to describe an innovative approach that combines reflexive and interactive engagement processes to (a) develop and design a framework to assess the GBR’s complex governance system health; and (b) undertake a benchmark assessment of governance system health. We drew upon appreciative inquiry and used multiple lines of evidence, including an extensive literature review, governance system mapping, focus group discussions and personal interviews. Together, these approaches allowed us to effectively engage key actors in value judgements about twenty key characteristic attributes of the governance system. These attributes were organised into four clusters which enabled us to broadly describe and benchmark the system. These included the following: (i) system coherence; (ii) connectivity and capacity; (iii) knowledge application; (iv) operational aspects of governance. This process facilitated deliberative discussion and consensus-building around attribute health and priorities for transformative action. This was achieved through the inclusion of diverse perspectives from across the governance system, analysis of rich datasets, and the provision of guidance from the project’s Steering Committee and Technical Working Group. Our inclusive, collaborative and deliberative approach, its analytical depth, and the framework’s repeatability enable continuous monitoring and adaptive improvement of the GBR governance system and can be readily applied to complex governance systems elsewhere. Full article
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9 pages, 1717 KiB  
Article
New Imaging Method of Mobile Phone-Based Colorimetric Sensor for Iron Quantification
by Ngan Anh Nguyen, Asher Hendricks, Emily Montoya, Amber Mayers, Diwitha Rajmohan, Aoife Morrin, Margaret McCaul, Nicholas Dunne, Noel O’Connor, Andreas Spanias, Gregory Raupp and Erica Forzani
Sensors 2025, 25(15), 4693; https://doi.org/10.3390/s25154693 (registering DOI) - 29 Jul 2025
Viewed by 173
Abstract
Blood iron levels are related to many health conditions, affecting hundreds of millions of individuals worldwide. To aid in the prevention and treatment of iron-related disorders, previous research has developed a low-cost, accurate, point-of-care method for measuring iron from a single finger-prick blood [...] Read more.
Blood iron levels are related to many health conditions, affecting hundreds of millions of individuals worldwide. To aid in the prevention and treatment of iron-related disorders, previous research has developed a low-cost, accurate, point-of-care method for measuring iron from a single finger-prick blood sample. This study builds upon that work by introducing an improved imaging method that accurately reads sensor images irrespective of variations in environmental illumination and camera quality. Smartphone cameras were used as analytical tools, demonstrating an average coefficient of variation of 5.13% across different phone models, and absorbance results were found to be improved by 8.80% compared to the method in a previous study. The proposed method successfully enhances iron detection accuracy under diverse lighting conditions, paving the way for smartphone-based sensing of other colorimetric reactions involving various analytes. Full article
(This article belongs to the Special Issue Colorimetric Sensors: Methods and Applications (2nd Edition))
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24 pages, 11697 KiB  
Article
Layered Production Allocation Method for Dual-Gas Co-Production Wells
by Guangai Wu, Zhun Li, Yanfeng Cao, Jifei Yu, Guoqing Han and Zhisheng Xing
Energies 2025, 18(15), 4039; https://doi.org/10.3390/en18154039 - 29 Jul 2025
Viewed by 162
Abstract
The synergistic development of low-permeability reservoirs such as deep coalbed methane (CBM) and tight gas has emerged as a key technology to reduce development costs, enhance single-well productivity, and improve gas recovery. However, due to fundamental differences between coal seams and tight sandstones [...] Read more.
The synergistic development of low-permeability reservoirs such as deep coalbed methane (CBM) and tight gas has emerged as a key technology to reduce development costs, enhance single-well productivity, and improve gas recovery. However, due to fundamental differences between coal seams and tight sandstones in their pore structure, permeability, water saturation, and pressure sensitivity, significant variations exist in their flow capacities and fluid production behaviors. To address the challenges of production allocation and main reservoir identification in the co-development of CBM and tight gas within deep gas-bearing basins, this study employs the transient multiphase flow simulation software OLGA to construct a representative dual-gas co-production well model. The regulatory mechanisms of the gas–liquid distribution, deliquification efficiency, and interlayer interference under two typical vertical stacking relationships—“coal over sand” and “sand over coal”—are systematically analyzed with respect to different tubing setting depths. A high-precision dynamic production allocation method is proposed, which couples the wellbore structure with real-time monitoring parameters. The results demonstrate that positioning the tubing near the bottom of both reservoirs significantly enhances the deliquification efficiency and bottomhole pressure differential, reduces the liquid holdup in the wellbore, and improves the synergistic productivity of the dual-reservoirs, achieving optimal drainage and production performance. Building upon this, a physically constrained model integrating real-time monitoring data—such as the gas and liquid production from tubing and casing, wellhead pressures, and other parameters—is established. Specifically, the model is built upon fundamental physical constraints, including mass conservation and the pressure equilibrium, to logically model the flow paths and phase distribution behaviors of the gas–liquid two-phase flow. This enables the accurate derivation of the respective contributions of each reservoir interval and dynamic production allocation without the need for downhole logging. Validation results show that the proposed method reliably reconstructs reservoir contribution rates under various operational conditions and wellbore configurations. Through a comparison of calculated and simulated results, the maximum relative error occurs during abrupt changes in the production capacity, approximately 6.37%, while for most time periods, the error remains within 1%, with an average error of 0.49% throughout the process. These results substantially improve the timeliness and accuracy of the reservoir identification. This study offers a novel approach for the co-optimization of complex multi-reservoir gas fields, enriching the theoretical framework of dual-gas co-production and providing technically adaptive solutions and engineering guidance for multilayer unconventional gas exploitation. Full article
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27 pages, 5740 KiB  
Article
Localization of Multiple GNSS Interference Sources Based on Target Detection in C/N0 Distribution Maps
by Qidong Chen, Rui Liu, Qiuzhen Yan, Yue Xu, Yang Liu, Xiao Huang and Ying Zhang
Remote Sens. 2025, 17(15), 2627; https://doi.org/10.3390/rs17152627 - 29 Jul 2025
Viewed by 245
Abstract
The localization of multiple interference sources in Global Navigation Satellite Systems (GNSS) can be achieved using carrier-to-noise ratio (C/N0) information provided by GNSS receivers, such as those embedded in smartphones. However, in increasingly prevalent complex scenarios—such as the coexistence of multiple [...] Read more.
The localization of multiple interference sources in Global Navigation Satellite Systems (GNSS) can be achieved using carrier-to-noise ratio (C/N0) information provided by GNSS receivers, such as those embedded in smartphones. However, in increasingly prevalent complex scenarios—such as the coexistence of multiple directional interferences, increased diversity and density of GNSS interference, and the presence of multiple low-power interference sources—conventional localization methods often fail to provide reliable results, thereby limiting their applicability in real-world environments. This paper presents a multi-interference sources localization method using object detection in GNSS C/N0 distribution maps. The proposed method first exploits the similarity between C/N0 data reported by GNSS receivers and image grayscale values to construct C/N0 distribution maps, thereby transforming the problem of multi-source GNSS interference localization into an object detection and localization task based on image processing techniques. Subsequently, an Oriented Squeeze-and-Excitation-based Faster Region-based Convolutional Neural Network (OSF-RCNN) framework is proposed to process the C/N0 distribution maps. Building upon the Faster R-CNN framework, the proposed method integrates an Oriented RPN (Region Proposal Network) to regress the orientation angles of directional antennas, effectively addressing their rotational characteristics. Additionally, the Squeeze-and-Excitation (SE) mechanism and the Feature Pyramid Network (FPN) are integrated at key stages of the network to improve sensitivity to small targets, thereby enhancing detection and localization performance for low-power interference sources. The simulation results verify the effectiveness of the proposed method in accurately localizing multiple interference sources under the increasingly prevalent complex scenarios described above. Full article
(This article belongs to the Special Issue Advanced Multi-GNSS Positioning and Its Applications in Geoscience)
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15 pages, 3624 KiB  
Article
A Spectroscopic DRIFT-FTIR Study on the Friction-Reducing Properties and Bonding of Railway Leaf Layers
by Ben White, Joseph Lanigan and Roger Lewis
Lubricants 2025, 13(8), 329; https://doi.org/10.3390/lubricants13080329 - 29 Jul 2025
Viewed by 182
Abstract
Leaves react with rail steel and form a tribofilm, causing very low friction in the wheel/rail interface. This work uses twin-disc tribological testing with the addition of leaf particulates to simulate the reaction and resulting reduction in the friction coefficient in a laboratory [...] Read more.
Leaves react with rail steel and form a tribofilm, causing very low friction in the wheel/rail interface. This work uses twin-disc tribological testing with the addition of leaf particulates to simulate the reaction and resulting reduction in the friction coefficient in a laboratory setting. Diffuse Reflectance Fourier-Transform Infrared Spectroscopy was carried out on the organic material and the layers that formed on the twin-disc surface. Dark material, visibly similar to leaf layers formed on tracks during autumn, was used along with a transparent thin film. This “non-visible contamination” has been reported to cause low-adhesion problems on railways, but has not previously been characterised. This article discusses the nature of these layers and builds upon earlier studies to propose a degradation and bonding mechanism for the leaf material. This understanding could be used to improve friction management methods employed to deal with low adhesion due to leaves. Full article
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