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Optimal pricing approaches for data markets in market-operated data exchanges
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作者 Yangming Lyu Linyi Qian +2 位作者 Zhixin Yang Jing Yao Xiaochen Zuo 《Statistical Theory and Related Fields》 2026年第1期23-45,共23页
This work contributes to the theoretical foundation for pricing in data markets and offers practical insights for managing digital data exchanges in the era of big data.We propose a structured pricing model for data e... This work contributes to the theoretical foundation for pricing in data markets and offers practical insights for managing digital data exchanges in the era of big data.We propose a structured pricing model for data exchanges transitioning from quasi-public to marketoriented operations.To address the complex dynamics among data exchanges,suppliers,and consumers,the authors develop a threestage Stackelberg game framework.In this model,the data exchange acts as a leader setting transaction commission rates,suppliers are intermediate leaders determining unit prices,and consumers are followers making purchasing decisions.Two pricing strategies are examined:the Independent Pricing Approach(IPA)and the novel Perfectly Competitive Pricing Approach(PCPA),which accounts for competition among data providers.Using backward induction,the study derives subgame-perfect equilibria and proves the existence and uniqueness of Stackelberg equilibria under both approaches.Extensive numerical simulations are carried out in the model,demonstrating that PCPA enhances data demander utility,encourages supplier competition,increases transaction volume,and improves the overall profitability and sustainability of data exchanges.Social welfare analysis further confirms PCPA’s superiority in promoting efficient and fair data markets. 展开更多
关键词 data exchange data market digital economy perfectly competitive pricing approach Stackelberg game
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Access and Privacy Control for Healthcare Decision Support System:A Smart Medical Data Exchange Engine(SMDEE)
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作者 Imran Khan Javed Rashid +3 位作者 Anwar Ghani Muhammad Shoaib Saleem Muhammad Faheem Humera Khan 《CAAI Transactions on Intelligence Technology》 2025年第6期1616-1632,共17页
Secure and automated sharing of medical information among different medical entities/stakeholders like patients,hospitals,doctors,law enforcement agencies,health insurance companies etc.,in a standard format has alway... Secure and automated sharing of medical information among different medical entities/stakeholders like patients,hospitals,doctors,law enforcement agencies,health insurance companies etc.,in a standard format has always been a challenging problem.Current methods for ensuring compliance with medical privacy laws require specialists who are deeply familiar with these laws'complex requirements to verify the lawful exchange of medical information.This article introduces a Smart Medical Data Exchange Engine(SDEE)designed to automate the extracting of logical rules from medical privacy legislation using advanced techniques.These rules facilitate the secure extraction of information,safeguarding patient privacy and confidentiality.In addition,SMDEE can generate standardised clinical documents according to Health Level 7(HL7)standards and also standardise the nomenclature of requested medical data,enabling accurate decision-making when accessing patient data.All access requests to patient information are processed through SMDEE to ensure authorised access.The proposed system's efficacy is evaluated using the Health Insurance Portability and Accountability Act(HIPAA),a fundamental privacy law in the United States.However,SMDEE's flexibility allows its application worldwide,accommodating various medical privacy laws.Beyond facilitating global information exchange,SMDEE aims to enhance international patients'timely and appropriate treatment. 展开更多
关键词 data protection decision making information retrieval intelligent information processing medical applications privacy issues security security of data
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Short-Term Spillover Effects in High-order Moments of Stocks, Foreign Currency Exchange and Bitcoin with Intraday Data
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作者 Xinying He 《Proceedings of Business and Economic Studies》 2025年第3期172-181,共10页
This paper employs Granger causality analysis and the generalized impulse response function(GIRF)to study the higher-order moment spillover effects among Bitcoin,stock markets,and foreign exchange markets in the U.S.U... This paper employs Granger causality analysis and the generalized impulse response function(GIRF)to study the higher-order moment spillover effects among Bitcoin,stock markets,and foreign exchange markets in the U.S.Using intraday high-frequency data,the research focuses on the interactions across higher-order moments,including volatility,jumps,skewness,and kurtosis.The results reveal significant bidirectional spillover effects between Bitcoin and traditional financial assets,particularly in terms of volatility and jump behavior,indicating that the cryptocurrency market has become a crucial component of global financial risk transmission.This study provides new theoretical perspectives and policy recommendations for global asset allocation,market regulation,and risk management,underscoring the importance of proactive management measures in addressing the complex risk interactions between cryptocurrencies and traditional financial markets. 展开更多
关键词 Higher-order moments Intraday data Spillover effects Bitcoin Risk management
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Synthesis,characterization,and ion exchange properties of octamolybdate-based Cu(Ⅱ)coordination polymer
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作者 HAO Xiuli ZHANG Chenhao +3 位作者 FENG Chenkun HAN Haolin ZHAO Xudong SHI Guoliang 《无机化学学报》 北大核心 2026年第4期883-896,共14页
The ionothermal reaction between CuCl_(2),1,4-bis(1,2,4-triazol-1-ylmethyl)benzene(BBTZ),and(NH_(4))_(6)Mo_(7)O_(24) in 1-ethyl-3-methylimidazolium bromide((Emim)Br)led to a new octamolybdate-based coordination polyme... The ionothermal reaction between CuCl_(2),1,4-bis(1,2,4-triazol-1-ylmethyl)benzene(BBTZ),and(NH_(4))_(6)Mo_(7)O_(24) in 1-ethyl-3-methylimidazolium bromide((Emim)Br)led to a new octamolybdate-based coordination polymer(Emim)2[Cu(BBTZ)_(2)(β-Mo_(8)O_(26))](Mo_(8)-CP).Mo_(8)-CP was characterized by elemental analysis,thermogravime-try,IR,powder X-ray diffraction,and single-crystal X-ray diffraction.In Mo_(8)-CP,structural analysis reveals that Cu coordinates with BBTZ ligands to form an interlocked 1D chain.These chains are further bridged by(β-Mo_(8)O_(26))^(4-)to construct a 3D coordination polymer.Notably,(Emim)^(+)acts as a structure-directing agent,occupying the channels of the 3D coordination polymer.Based on this unique structure,the ion exchange properties of Mo_(8)-CP toward rare-earth ions were investigated.It has been found that the luminescent color of the material can be successfully regulat-ed by introducing Eu^(3+)or Tb^(3+)through ion exchange.CCDC:2475110,Mo_(8)-CP. 展开更多
关键词 OCTAMOLYBDATE coordination polymer ion exchange property fluorescent materials
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Spatio-Temporal Earthquake Analysis via Data Warehousing for Big Data-Driven Decision Systems
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作者 Georgia Garani George Pramantiotis Francisco Javier Moreno Arboleda 《Computers, Materials & Continua》 2026年第3期1963-1988,共26页
Earthquakes are highly destructive spatio-temporal phenomena whose analysis is essential for disaster preparedness and risk mitigation.Modern seismological research produces vast volumes of heterogeneous data from sei... Earthquakes are highly destructive spatio-temporal phenomena whose analysis is essential for disaster preparedness and risk mitigation.Modern seismological research produces vast volumes of heterogeneous data from seismic networks,satellite observations,and geospatial repositories,creating the need for scalable infrastructures capable of integrating and analyzing such data to support intelligent decision-making.Data warehousing technologies provide a robust foundation for this purpose;however,existing earthquake-oriented data warehouses remain limited,often relying on simplified schemas,domain-specific analytics,or cataloguing efforts.This paper presents the design and implementation of a spatio-temporal data warehouse for seismic activity.The framework integrates spatial and temporal dimensions in a unified schema and introduces a novel array-based approach for managing many-to-many relationships between facts and dimensions without intermediate bridge tables.A comparative evaluation against a conventional bridge-table schema demonstrates that the array-based design improves fact-centric query performance,while the bridge-table schema remains advantageous for dimension-centric queries.To reconcile these trade-offs,a hybrid schema is proposed that retains both representations,ensuring balanced efficiency across heterogeneous workloads.The proposed framework demonstrates how spatio-temporal data warehousing can address schema complexity,improve query performance,and support multidimensional visualization.In doing so,it provides a foundation for integrating seismic analysis into broader big data-driven intelligent decision systems for disaster resilience,risk mitigation,and emergency management. 展开更多
关键词 data warehouse data analysis big data decision systems SEISMOLOGY data visualization
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Carbon Supported Octahedral PtNi Nanoparticles(Oct-PtNi/C)as a Cathode Catalyst for Proton Exchange Membrane Fuel Cells(PEMFCs)with Improved Activity and Durability
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作者 Zi-Wei Feng Hai-Zhong Chen +3 位作者 Xiao Duan Ling Tang Yun-Kun Zhao Long Huang 《电化学(中英文)》 北大核心 2026年第1期65-76,共12页
Proton exchange membrane fuel cells(PEMFCs)are considered as a promising renewable power source.However,the massive commercial application of PEMFCs has been greatly hindered by their high expense and less-satisfied p... Proton exchange membrane fuel cells(PEMFCs)are considered as a promising renewable power source.However,the massive commercial application of PEMFCs has been greatly hindered by their high expense and less-satisfied performance mainly due to the sluggish oxygen reduction reaction(ORR)kinetics even on state-of-the-art Pt catalyst.Octahedral PtNi nanoparticles(oct-PtNi NPs)with excellent ORR activity in a half-cell have been widely studied,while their performance in membrane electrode assembly(MEA)has much less reported.Herein,we investigated the MEA performance using the carbon supported oct-PtNi NPs(oct-PtNi/C)as the cathode catalyst.Under the mild acid washing condition,the surface Ni atoms of oct-PtNi/C were largely removed,and the performance of the MEA using the acid-leaching oct-PtNi/C(PNC-A)as the cathode catalyst was greatly improved.The maximum power density of the MEA reached 1.0 W·cm^(-2) with the cath-ode Pt loading of 0.2 mg·cm^(-2),which is 15%higher than that using Pt/C as the catalyst.After 30k cycles in the accelerated degradation test(ADT),the MEA using PNC-A as the catalyst showed a performance retention of 82%,higher than that of Pt/C(74%).The results reported here verify the possibility of using PNC-A as an advanced cathode catalyst in PEMFCs,thus enhancing the performance of PEMFCs while lowering the amount of expensive Pt. 展开更多
关键词 Proton exchange membrane fuel cell Octahedral PtNi Oxygen reduction reaction Membrane electrode assembly
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Promoting Cultural Exchange Through Thangka
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作者 LI YUAN 《China Today》 2026年第1期72-75,共4页
A Tibetan art form bridges the past and present and connects cultures around the world.THANGKA,a unique form of Tibetan sacred painting,is gaining prominence globally due to its vibrant colors,exquisite craftsmanship,... A Tibetan art form bridges the past and present and connects cultures around the world.THANGKA,a unique form of Tibetan sacred painting,is gaining prominence globally due to its vibrant colors,exquisite craftsmanship,and profound religious and cultural significance.With the acceleration of globalization,this symbol of Tibetan culture that combines artistic expression with spirituality has become a bridge for cultural exchange between the East and the West.Recently,China Today spoke to Yixi Puncog,art collector and council member of the China Association for Preservation and Development of Tibetan Culture,to learn more about Thangka art,its role in international exchange,and how it is enhancing China’s cultural soft power. 展开更多
关键词 GLOBALIZATION cultural exchange Tibetan art yixi puncogart international exchange thangka artistic expression cultural soft power
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Analysis of Ningxia’s Tourism Culture and Ethnic Exchange,Communication and Integration
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作者 SHI Ruiqing 《Cultural and Religious Studies》 2026年第1期78-82,共5页
Ningxia is an ethnic gathering area boasting abundant tourism and cultural resources.Developing the cause of tourism and culture is an important way to encourage all ethnic groups to respect differences,embrace divers... Ningxia is an ethnic gathering area boasting abundant tourism and cultural resources.Developing the cause of tourism and culture is an important way to encourage all ethnic groups to respect differences,embrace diversity,and demonstrate their interactions,exchanges,and integration in tourism activities.As an important preserve of the distinctive cultures of the Chinese nation and a prominent world tourist destination,Ningxia should strive to foster and consolidate the sense of a community with a shared future for the Chinese nation in developing its tourism and culture under the new historical conditions.It is imperative to advance the prosperity and development of tourism and culture in boosting ethnic interactions,exchanges,and integration through the formulation of tourism and cultural policies and plans,as well as the development and design of tourism and cultural projects. 展开更多
关键词 Ningxia tourism culture exchange communication and integration
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Explainable Ensemble Learning Approach for Ovarian Cancer Diagnosis Using Clinical Data
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作者 Daniyal Asif Nabil Kerdid +1 位作者 Muhammad Shoaib Arif Mairaj Bibi 《Computer Modeling in Engineering & Sciences》 2026年第3期1050-1076,共27页
Ovarian cancer(OC)is one of the leading causes of death related to gynecological cancer,with the main difficulty of its early diagnosis and a heterogeneous nature of tumor biomarkers.Machine learning(ML)has the potent... Ovarian cancer(OC)is one of the leading causes of death related to gynecological cancer,with the main difficulty of its early diagnosis and a heterogeneous nature of tumor biomarkers.Machine learning(ML)has the potential to process complex datasets and support decision-making in OC diagnosis.Nevertheless,traditional ML models tend to be biased,overfitting,noisy,and less generalized.Moreover,their black-box nature reduces interpretability and limits their practical clinical applicability.In this study,we introduce an explainable ensemble learning(EL)model,TreeX-Stack,based on a stacking architecture that employs tree-based learners such as Decision Tree(DT),Random Forest(RF),Gradient Boosting(GB),and Extreme Gradient Boosting(XGBoost)as base learners,and Logistic Regression(LR)as the meta-learner to enhance ovarian cancer(OC)diagnosis.Local Interpretable ModelAgnostic Explanations(LIME)are used to explain individual predictions,making the model outputs more clinically interpretable and applicable.The model is trained on the dataset that includes demographic information,blood test,general chemistry,and tumor markers.Extensive preprocessing includes handling missing data using iterative imputation with Bayesian Ridge and addressing multicollinearity by removing features with correlation coefficients above 0.7.Relevant features are then selected using the Boruta feature selection method.To obtain robust and unbiased performance estimates during hyperparameter tuning,nested cross-validation(CV)with grid search is employed,and all experiments are repeated five times to ensure statistical reliability.TreeX-Stack demonstrates excellent diagnostic performance,achieving an accuracy of 0.9027,a precision of 0.8673,a recall of 0.9391,and an F1-score of 0.9012.Feature-importance analyses using LIME and permutation importance highlight Human Epididymis Protein 4(HE4)as the most significant biomarker for OC.The combination of high predictive performance and interpretability makes TreeX-Stack a reliable tool for clinical decision support in OC diagnosis. 展开更多
关键词 Ovarian cancer ensemble learning machine learning STACKING explainable artificial intelligence medical data analysis clinical data HE4
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Combining different climate datasets better reflects the response of warm-temperate forests to climate:a case study from Mt.Dongling,Beijing
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作者 Shengjie Wang Haiyang Liu +1 位作者 Shuai Yuan Chenxi Xu 《Journal of Forestry Research》 2026年第2期131-143,共13页
Accurately assessing the relationship between tree growth and climatic factors is of great importance in dendrochronology.This study evaluated the consistency between alternative climate datasets(including station and... Accurately assessing the relationship between tree growth and climatic factors is of great importance in dendrochronology.This study evaluated the consistency between alternative climate datasets(including station and gridded data)and actual climate data(fixed-point observations near the sampling sites),in northeastern China’s warm temperate zone and analyzed differences in their correlations with tree-ring width index.The results were:(1)Gridded temperature data,as well as precipitation and relative humidity data from the Huailai meteorological station,was more consistent with the actual climate data;in contrast,gridded soil moisture content data showed significant discrepancies.(2)Horizontal distance had a greater impact on the representativeness of actual climate conditions than vertical elevation differences.(3)Differences in consistency between alternative and actual climate data also affected their correlations with tree-ring width indices.In some growing season months,correlation coefficients,both in magnitude and sign,differed significantly from those based on actual data.The selection of different alternative climate datasets can lead to biased results in assessing forest responses to climate change,which is detrimental to the management of forest ecosystems in harsh environments.Therefore,the scientific and rational selection of alternative climate data is essential for dendroecological and climatological research. 展开更多
关键词 Climate data representativeness Alternative climate data selection Response differences Deciduous broad-leaf forest Warm temperate zone
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Construction and Application Practice of the Data-driven Comprehensive Management Platform for Regional Air Quality
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作者 Tongxing ZHANG Yun WU Yongwen LI 《Meteorological and Environmental Research》 2026年第1期21-28,共8页
To address the severe challenges of PM_(2.5) and ozone co-control during the"14^(th) Five-Year Plan"period and to enhance the precision and intelligence level of air environment governance,it is imperative t... To address the severe challenges of PM_(2.5) and ozone co-control during the"14^(th) Five-Year Plan"period and to enhance the precision and intelligence level of air environment governance,it is imperative to build an efficient comprehensive management platform for regional air quality.In this paper,the specific practice in Zibo City,Shandong Province is as an example to systematically analyze the top-level design,technical implementation,and innovative application of a comprehensive management platform for regional air quality integrating"perception monitoring,data fusion,research judgment of early warnings,analysis of sources,collaborative dispatching,and evaluation assessment".Through the construction of an"sky-air-ground"integrated three-dimensional monitoring network,the platform integrates multi-source heterogeneous environmental data,and employs big data,cloud computing,artificial intelligence,CALPUFF/CMAQ,and other numerical model technologies to achieve comprehensive perception,precise prediction,intelligent source tracing,and closed-loop management of air pollution.The platform innovatively establishes a full-process closed-loop management mechanism of"data-early warning-disposition-evaluation",and achieves a fundamental transformation from passive response to active anticipation and from experience-based judgment to data driving in environmental supervision.The application results show that this platform significantly improves the scientific decision-making ability and collaborative execution efficiency of air pollution governance in Zibo City,providing a replicable and scalable comprehensive solution for similar industrial cities to achieve the continuous improvement of air quality. 展开更多
关键词 Comprehensive management of air quality Big data Internet of Things Closed-loop management data driving Off-site supervision
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Quaternary Ammonium Groups Modified Cross-linked Poly-benzimidazole for Catalyst Slurry and Proton Exchange Membranes in Fuel Cell
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作者 LI Yaohu LOU Wenbo PAN Hongfei 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期285-295,共11页
We successfully incorporated phenyl groups into a small-molecule quaternary ammonium cross-linker and synthesized cross-linked polybenzimidazole membranes via a one-step cross-linking process.Compared with conventiona... We successfully incorporated phenyl groups into a small-molecule quaternary ammonium cross-linker and synthesized cross-linked polybenzimidazole membranes via a one-step cross-linking process.Compared with conventional quaternary ammonium-crosslinked benzimidazole membranes,the introduction of phenyl groups significantly increases the free volume within the membrane.After phosphoric acid doping,the benzimidazole membrane with larger free volume retains more phosphoric acid compared to conventional quaternary ammonium-crosslinked membranes,forming an extensive hydrogen-bonding network that effectively enhances its anhydrous proton conductivity.The anhydrous proton conductivity reaches 91 mS·cm^(-1)at 160℃,substantially higher than that of conventional quaternary ammonium-crosslinked membranes with the same mass fraction.Benefiting from the improved conductivity,the membrane electrode assembly exhibits reduced ohmic polarization,achieving a peak power density of 792 mW·cm^(-2)at 160℃. 展开更多
关键词 proton exchange membrane cross-linked structure free volume proton conductivity
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tsRNADisease:a manually curated database of tsRNAs associated with human disease
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作者 Hui Yang Shaoying Zhu +5 位作者 Huijun Wei Wei Huang Qi Chen Yungang He Kun Lv Zhen Yang 《Journal of Genetics and Genomics》 2026年第3期537-543,共7页
tRNA-derived small RNAs(tsRNAs),as a class of regulatory small noncoding RNA,have been implicated in a wide variety of human diseases.Large amounts of tsRNA–disease associations have been identified in recent years f... tRNA-derived small RNAs(tsRNAs),as a class of regulatory small noncoding RNA,have been implicated in a wide variety of human diseases.Large amounts of tsRNA–disease associations have been identified in recent years from accumulating studies.However,repositories for cataloging the detailed information on tsRNA–disease associations are scarce.In this study,we provide a tsRNADisease database by integrating experimentally and computationally supported tsRNA–disease associations from manual curation of literatures and other related resources.tsRNADisease contains 5571 manually curated associations between 4759 tsRNAs and 166 diseases with experimental evidence from 346 studies.In addition,it also contains 5013 predicted associations between 1297 tsRNAs and 111 diseases.tsRNADisease provides a user-friendly interface to browse,retrieve,and download data conveniently.This database can improve our understanding of tsRNA deregulation in diseases and serve as a valuable resource for investigating the mechanism of disease-related tsRNAs.tsRNADisease is freely available at http://www.compgenelab.info/tsRNADisease. 展开更多
关键词 tsRNA DISEASE CANCER data integration dataBASE
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Data-Driven Research Drives Earth System Science
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作者 Xing Yu Shufeng Yang 《Journal of Earth Science》 2026年第1期361-367,共7页
0 INTRODUCTION Earth science is a natural science concerned with the composition,dynamics,spatiotemporal evolution,and formation mechanisms of Earth materials(Chen and Yang,2023).Traditional Earth science research has... 0 INTRODUCTION Earth science is a natural science concerned with the composition,dynamics,spatiotemporal evolution,and formation mechanisms of Earth materials(Chen and Yang,2023).Traditional Earth science research has largely been discipline-based,relying on field investigations,data collection,experimental analyses,and data interpretation to study individual components of the Earth system. 展开更多
关键词 natural science data interpretation earth system science field investigationsdata earth science COMPOSITION study individual components earth system data driven research
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An Anonymous Authentication and Key Exchange Protocol for UAVs in Flying Ad-Hoc Networks
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作者 Yanan Liu Suhao Wang +4 位作者 Lei Cao Pengfei Wang Zheng Zhang Shuo Qiu Ruchan Dong 《Computers, Materials & Continua》 2026年第3期1262-1286,共25页
Unmanned Aerial Vehicles(UAVs)in Flying Ad-Hoc Networks(FANETs)are widely used in both civilian and military fields,but they face severe security,trust,and privacy vulnerabilities due to their high mobility,dynamic to... Unmanned Aerial Vehicles(UAVs)in Flying Ad-Hoc Networks(FANETs)are widely used in both civilian and military fields,but they face severe security,trust,and privacy vulnerabilities due to their high mobility,dynamic topology,and open wireless channels.Existing security protocols for Mobile Ad-Hoc Networks(MANETs)cannot be directly applied to FANETs,as FANETs require lightweight,high real-time performance,and strong anonymity.The current FANETs security protocol cannot simultaneously meet the requirements of strong anonymity,high security,and low overhead in high dynamic and resource-constrained scenarios.To address these challenges,this paper proposes an Anonymous Authentication and Key Exchange Protocol(AAKE-OWA)for UAVs in FANETs based on OneWay Accumulators(OWA).During the UAV registration phase,the Key Management Center(KMC)generates an identity ticket for each UAV using OWA and transmits it securely to the UAV’s on-board tamper-proof module.In the key exchange phase,UAVs generate temporary authentication tickets with random numbers and compute the same session key leveraging the quasi-commutativity of OWA.For mutual anonymous authentication,UAVs encrypt random numbers with the session key and verify identities by comparing computed values with authentication values.Formal analysis using the Scyther tool confirms that the protocol resists identity spoofing,man-in-the-middle,and replay attacks.Through Burrows Abadi Needham(BAN)logic proof,it achieves mutual anonymity,prevents simulation and physical capture attacks,and ensures secure connectivity of 1.Experimental comparisons with existing protocols prove that the AAKE-OWA protocol has lower computational overhead,communication overhead,and storage overhead,making it more suitable for resource-constrained FANET scenarios.Performance comparison experiments show that,compared with other schemes,this scheme only requires 8 one-way accumulator operations and 4 symmetric encryption/decryption operations,with a total computational overhead as low as 2.3504 ms,a communication overhead of merely 1216 bits,and a storage overhead of 768 bits.We have achieved a reduction in computational costs from 6.3%to 90.3%,communication costs from 5.0%to 69.1%,and overall storage costs from 33%to 68%compared to existing solutions.It can meet the performance requirements of lightweight,real-time,and anonymity for unmanned aerial vehicles(UAVs)networks. 展开更多
关键词 AUTHENTICATION key exchange one-way accumulator flying ad-hoc networks SECURITY
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Photoacoustic-computed tomography 3D data compression method and system based on Wavelet-Transformer
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作者 Jialin Li Tingting Li +2 位作者 Yiming Ma Yi Shen Mingjian Sun 《Journal of Innovative Optical Health Sciences》 2026年第1期110-125,共16页
Photoacoustic-computed tomography is a novel imaging technique that combines high absorption contrast and deep tissue penetration capability,enabling comprehensive three-dimensional imaging of biological targets.Howev... Photoacoustic-computed tomography is a novel imaging technique that combines high absorption contrast and deep tissue penetration capability,enabling comprehensive three-dimensional imaging of biological targets.However,the increasing demand for higher resolution and real-time imaging results in significant data volume,limiting data storage,transmission and processing efficiency of system.Therefore,there is an urgent need for an effective method to compress the raw data without compromising image quality.This paper presents a photoacoustic-computed tomography 3D data compression method and system based on Wavelet-Transformer.This method is based on the cooperative compression framework that integrates wavelet hard coding with deep learning-based soft decoding.It combines the multiscale analysis capability of wavelet transforms with the global feature modeling advantage of Transformers,achieving high-quality data compression and reconstruction.Experimental results using k-wave simulation suggest that the proposed compression system has advantages under extreme compression conditions,achieving a raw data compression ratio of up to 1:40.Furthermore,three-dimensional data compression experiment using in vivo mouse demonstrated that the maximum peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)values of reconstructed images reached 38.60 and 0.9583,effectively overcoming detail loss and artifacts introduced by raw data compression.All the results suggest that the proposed system can significantly reduce storage requirements and hardware cost,enhancing computational efficiency and image quality.These advantages support the development of photoacoustic-computed tomography toward higher efficiency,real-time performance and intelligent functionality. 展开更多
关键词 Photoacoustic-computed tomography data compression TRANSFORMER
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A Review on Applications and Challenges of Fullerenes in Proton Exchange Membranes
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作者 Ruslan Usmanov Alexander Pozdnyakov 《Carbon Energy》 2026年第2期156-186,共31页
Clean energy devices have the potential to change the world and avoid future energy crises.The development of new energyefficient technologies helps reduce our dependence on limited fossil fuel resources.Hydrogen ener... Clean energy devices have the potential to change the world and avoid future energy crises.The development of new energyefficient technologies helps reduce our dependence on limited fossil fuel resources.Hydrogen energy is the key to achieving clean energy transition goals.Proton exchange membrane fuel cells play a critical role.Research and development of new hightech proton exchange membranes(PEMs)provide new horizons for the development of hydrogen energy.The use of carbon nanomaterials to improve PEM efficiency is one of the modern trends.The modification of modern membranes with fullerenes and their derivatives is an innovative strategy for increasing proton conductivity.This paper discusses the key principles of proton transport in PEMs modified with individual fullerenols,sulfofullerenes,carboxylated fullerenes,phosphofullerenes,and cianohydrofullerenes.The introduction of fullerene nanoparticles into polymer PEM induces an improvement in key properties.Summary information covers existing research on the use of fullerenes as nanoscale modifiers of proton-conducting materials.This review will help researchers to surpass the achieved results in the field of modern proton-conducting materials and stimulate the development of hydrogen energy. 展开更多
关键词 composite proton exchange membranes fuel cells FULLERENES functionalized fullerenes
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Covalent organic framework ionomers enable synergistic efficient transport of protons and oxygen in medium-temperature proton exchange membrane fuel cells
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作者 Zijie Lin Qing Li 《Chinese Chemical Letters》 2026年第1期7-9,共3页
Covalent organic framework ionomers enable synergistic efficient transport of protons and oxygen in medium-temperature proton exchange membrane fuel cells Proton exchange membrane fuel cells(PEMFCs),as clean and effic... Covalent organic framework ionomers enable synergistic efficient transport of protons and oxygen in medium-temperature proton exchange membrane fuel cells Proton exchange membrane fuel cells(PEMFCs),as clean and efficient energy technologies,are constrained in their performance enhancement by the sluggish oxygen reduction reaction(ORR)kinetics at the cathode,anode CO poisoning(e.g.,from methanol crossover)and intricate water management dilemmas[1]. 展开更多
关键词 covalent organic framework ionomers proton exchange membrane fuel cells pemfcs proton exchange membrane fuel cells sluggish oxygen reduction reaction orr kinetics PROTONS water management dilemmas OXYGEN
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An intelligent ion goalkeeper:a synergistically enhanced ion exchange membrane via multilayer interfacial assembly for vanadium flow batteries
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作者 Wei Xiao Yuanyuan Zhang +9 位作者 Zhaohan Meng Kai Zhang Yidan Sun Yue Yang Hebin Wang Jingze Hu Xuan Yuan Xihao Zhang Jiaqi Liu Denghua Zhang 《Materials Futures》 2026年第2期92-107,共16页
The intractable trade-off between proton conductivity and vanadium ion selectivity,known as the‘transmission paradox’is a critical bottleneck hindering the commercialization of vanadium flow batteries(VFBs).Inspired... The intractable trade-off between proton conductivity and vanadium ion selectivity,known as the‘transmission paradox’is a critical bottleneck hindering the commercialization of vanadium flow batteries(VFBs).Inspired by the multi-stage,synergistic filtration mechanism of the mammalian glomerular filtration barrier,a novel,biomimetic hierarchical composite membrane has been fabricated via a precise layer-by-layer strategy on a polyethylene(PE)substrate.This membrane integrates a polydopamine(PDA)adhesion layer,a sulfonated Zr-MOF ion-sieving layer,and a synergistic polybenzimidazole(PBI)matrix.Spectroscopic analysis confirmed the formation of a critical bifunctional acid-base interface(-SO_(3)^(−)…H^(+)N-)between the MOF and PBI,which densifies the structure and optimizes ion pathways.The resulting composite membrane exhibits excellent mechanical robustness,superior chemical stability,and exceptional dimensional stability.Most significantly,this architecture successfully decouples the performance trade-off,demonstrating both high proton conductivity(11.11 mS·cm^(-1))and remarkably suppressed vanadium ion permeability(2.4×10^(−8) cm^(2)·min^(-1)).This combination yields an outstanding ion selectivity of 46.29×10^(4) S·min·cm^(-3).When tested in a VFB single cell,the membrane enabled a high energy efficiency of 81.6%at 200 mA·cm^(-2),an ultra-long self-discharge time of 2700 min,and excellent long-term cycling stability.This biomimetic design strategy effectively resolves the core‘transmission paradox’offering a promising pathway for next-generation high-performance flow batteries. 展开更多
关键词 vanadium flow battery POLYBENZIMIDAZOLE POLYETHYLENE ion selectivity ion exchange membrane
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Planar-conjugated hyperbranched poly(aryl piperidinium)anion exchange membranes for sustainable energy devices
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作者 Weiting Gao Jiajun Li +1 位作者 Xuelang Gao Qinglin Liu 《Journal of Energy Chemistry》 2026年第3期397-406,共10页
Anion exchange membranes(AEMs)are pivotal for advancing fuel cells and water electrolysis.However,their widespread adoption is hindered by the sluggish ion transport and inadequate durability.Herein,by tuning the numb... Anion exchange membranes(AEMs)are pivotal for advancing fuel cells and water electrolysis.However,their widespread adoption is hindered by the sluggish ion transport and inadequate durability.Herein,by tuning the number of conjugated aromatic rings and the branching sites within the monomers,a series of hyperbranched poly(aryl piperidinium)AEMs with coplanar polycyclic aromatic units are prepared to address the poor mechanical properties of rigid conjugated AEMs.The results indicate that the introduction of planar-conjugated triphenylene(TY)units in the polymer backbone facilitates ordered interchain aggregation driven byπ-πstacking interaction to form well-defined ion-conductive channels while suppressing excessive swelling and enhancing the membrane stability.The hyperbranched AEM containing the TY units(QTPTY)possesses excellent mechanical properties with 55.9 MPa of stress and 60.3%of strain.Additionally,the QTPTY membrane achieves an exceptional OH-conductivity of 146.4 m S cm^(-1)at 80℃,with 94.7%conductivity retention and mechanical properties reduction below 2%after 1600 h in 2 M Na OH.In an H_(2)/O_(2) fuel cell,QTPTY delivers a peak power density of 1.43 W cm^(-2),surpassing linear and the other twoπ-conjugated hyperbranched analogs.In water electrolysis,the AEM exhibits a current density of 2.30 A cm^(-2)at 1.80 V,exceeding the 2026 targets of the U.S.Department of Energy.This work demonstrates that planar-conjugated hyperbranched architectures have a significant potential in designing robust,high-performance AEMs for sustainable energy technologies. 展开更多
关键词 Anion exchange membranes Planar-conjugated hyperbranched polymers Fuel cells Water electrolysis
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