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ISTIRDA:An Efficient Data Availability Sampling Scheme for Lightweight Nodes in Blockchain
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作者 Jiaxi Wang Wenbo Sun +3 位作者 Ziyuan Zhou Shihua Wu Jiang Xu Shan Ji 《Computers, Materials & Continua》 2026年第4期685-700,共16页
Lightweight nodes are crucial for blockchain scalability,but verifying the availability of complete block data puts significant strain on bandwidth and latency.Existing data availability sampling(DAS)schemes either re... Lightweight nodes are crucial for blockchain scalability,but verifying the availability of complete block data puts significant strain on bandwidth and latency.Existing data availability sampling(DAS)schemes either require trusted setups or suffer from high communication overhead and low verification efficiency.This paper presents ISTIRDA,a DAS scheme that lets light clients certify availability by sampling small random codeword symbols.Built on ISTIR,an improved Reed–Solomon interactive oracle proof of proximity,ISTIRDA combines adaptive folding with dynamic code rate adjustment to preserve soundness while lowering communication.This paper formalizes opening consistency and prove security with bounded error in the random oracle model,giving polylogarithmic verifier queries and no trusted setup.In a prototype compared with FRIDA under equal soundness,ISTIRDA reduces communication by 40.65%to 80%.For data larger than 16 MB,ISTIRDA verifies faster and the advantage widens;at 128 MB,proofs are about 60%smaller and verification time is roughly 25%shorter,while prover overhead remains modest.In peer-to-peer emulation under injected latency and loss,ISTIRDA reaches confidence more quickly and is less sensitive to packet loss and load.These results indicate that ISTIRDA is a scalable and provably secure DAS scheme suitable for high-throughput,large-block public blockchains,substantially easing bandwidth and latency pressure on lightweight nodes. 展开更多
关键词 Blockchain scalability data availability sampling lightweight nodes
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Towards Decentralized IoT Security: Optimized Detection of Zero-Day Multi-Class Cyber-Attacks Using Deep Federated Learning
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作者 Misbah Anwer Ghufran Ahmed +3 位作者 Maha Abdelhaq Raed Alsaqour Shahid Hussain Adnan Akhunzada 《Computers, Materials & Continua》 2026年第1期744-758,共15页
The exponential growth of the Internet of Things(IoT)has introduced significant security challenges,with zero-day attacks emerging as one of the most critical and challenging threats.Traditional Machine Learning(ML)an... The exponential growth of the Internet of Things(IoT)has introduced significant security challenges,with zero-day attacks emerging as one of the most critical and challenging threats.Traditional Machine Learning(ML)and Deep Learning(DL)techniques have demonstrated promising early detection capabilities.However,their effectiveness is limited when handling the vast volumes of IoT-generated data due to scalability constraints,high computational costs,and the costly time-intensive process of data labeling.To address these challenges,this study proposes a Federated Learning(FL)framework that leverages collaborative and hybrid supervised learning to enhance cyber threat detection in IoT networks.By employing Deep Neural Networks(DNNs)and decentralized model training,the approach reduces computational complexity while improving detection accuracy.The proposed model demonstrates robust performance,achieving accuracies of 94.34%,99.95%,and 87.94%on the publicly available kitsune,Bot-IoT,and UNSW-NB15 datasets,respectively.Furthermore,its ability to detect zero-day attacks is validated through evaluations on two additional benchmark datasets,TON-IoT and IoT-23,using a Deep Federated Learning(DFL)framework,underscoring the generalization and effectiveness of the model in heterogeneous and decentralized IoT environments.Experimental results demonstrate superior performance over existing methods,establishing the proposed framework as an efficient and scalable solution for IoT security. 展开更多
关键词 Cyber-attack intrusion detection system(IDS) deep federated learning(DFL) zero-day attack distributed denial of services(DDoS) MULTI-CLASS Internet of Things(IoT)
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Computer Aided Analysis of Lectin Proteins from Various Fungal Groups
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作者 Subramanian Third Nirai Senthil Kalayanaraman Rajagopal +1 位作者 Annamalai Jothi Thirunavukarasu Kamalakannan 《通讯和计算机(中英文版)》 2012年第2期134-136,共3页
关键词 血凝素蛋白 菌群体 计算机辅助 系统发育分析 碳水化合物 免疫球蛋白 氨基酸序列 凝集素
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AI-Enhanced Secure Data Aggregation for Smart Grids with Privacy Preservation
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作者 Congcong Wang Chen Wang +1 位作者 Wenying Zheng Wei Gu 《Computers, Materials & Continua》 SCIE EI 2025年第1期799-816,共18页
As smart grid technology rapidly advances,the vast amount of user data collected by smart meter presents significant challenges in data security and privacy protection.Current research emphasizes data security and use... As smart grid technology rapidly advances,the vast amount of user data collected by smart meter presents significant challenges in data security and privacy protection.Current research emphasizes data security and user privacy concerns within smart grids.However,existing methods struggle with efficiency and security when processing large-scale data.Balancing efficient data processing with stringent privacy protection during data aggregation in smart grids remains an urgent challenge.This paper proposes an AI-based multi-type data aggregation method designed to enhance aggregation efficiency and security by standardizing and normalizing various data modalities.The approach optimizes data preprocessing,integrates Long Short-Term Memory(LSTM)networks for handling time-series data,and employs homomorphic encryption to safeguard user privacy.It also explores the application of Boneh Lynn Shacham(BLS)signatures for user authentication.The proposed scheme’s efficiency,security,and privacy protection capabilities are validated through rigorous security proofs and experimental analysis. 展开更多
关键词 Smart grid data security privacy protection artificial intelligence data aggregation
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A Hybrid Machine Learning and Blockchain Framework for IoT DDoS Mitigation
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作者 Singamaneni Krishnapriya Sukhvinder Singh 《Computer Modeling in Engineering & Sciences》 2025年第8期1849-1881,共33页
The explosive expansion of the Internet of Things(IoT)systems has increased the imperative to have strong and robust solutions to cyber Security,especially to curtail Distributed Denial of Service(DDoS)attacks,which c... The explosive expansion of the Internet of Things(IoT)systems has increased the imperative to have strong and robust solutions to cyber Security,especially to curtail Distributed Denial of Service(DDoS)attacks,which can cripple critical infrastructure.The proposed framework presented in the current paper is a new hybrid scheme that induces deep learning-based traffic classification and blockchain-enabledmitigation tomake intelligent,decentralized,and real-time DDoS countermeasures in an IoT network.The proposed model fuses the extracted deep features with statistical features and trains them by using traditional machine-learning algorithms,which makes them more accurate in detection than statistical features alone,based on the Convolutional Neural Network(CNN)architecture,which can extract deep features.A permissioned blockchain will be included to record the threat cases immutably and automatically execute mitigation measures through smart contracts to provide transparency and resilience.When tested on two test sets,BoT-IoT and IoT-23,the framework obtains a maximum F1-score at 97.5 percent and only a 1.8 percent false positive rate,which compares favorably to other solutions regarding effectiveness and the amount of time required to respond.Our findings support the feasibility of our method as an extensible and secure paradigm of nextgeneration IoT security,which has constrictive utility in mission-critical or resource-constrained settings.The work is a substantial milestone in autonomous and trustful mitigation against DDoS attacks through intelligent learning and decentralized enforcement. 展开更多
关键词 IoT security DDoS mitigation machine learning CNN random forest blockchain smart contracts cyberattack detection
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Evaluating Method of Lower Limb Coordination Based on Spatial-Temporal Dependency Networks
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作者 Xuelin Qin Huinan Sang +3 位作者 Shihua Wu Shishu Chen Zhiwei Chen Yongjun Ren 《Computers, Materials & Continua》 2025年第10期1959-1980,共22页
As an essential tool for quantitative analysis of lower limb coordination,optical motion capture systems with marker-based encoding still suffer from inefficiency,high costs,spatial constraints,and the requirement for... As an essential tool for quantitative analysis of lower limb coordination,optical motion capture systems with marker-based encoding still suffer from inefficiency,high costs,spatial constraints,and the requirement for multiple markers.While 3D pose estimation algorithms combined with ordinary cameras offer an alternative,their accuracy often deteriorates under significant body occlusion.To address the challenge of insufficient 3D pose estimation precision in occluded scenarios—which hinders the quantitative analysis of athletes’lower-limb coordination—this paper proposes a multimodal training framework integrating spatiotemporal dependency networks with text-semantic guidance.Compared to traditional optical motion capture systems,this work achieves low-cost,high-precision motion parameter acquisition through the following innovations:(1)spatiotemporal dependency attention module is designed to establish dynamic spatiotemporal correlation graphs via cross-frame joint semantic matching,effectively resolving the feature fragmentation issue in existing methods.(2)noise-suppressed multi-scale temporal module is proposed,leveraging KL divergence-based information gain analysis for progressive feature filtering in long-range dependencies,reducing errors by 1.91 mm compared to conventional temporal convolutions.(3)text-pose contrastive learning paradigm is introduced for the first time,where BERT-generated action descriptions align semantic-geometric features via the BERT encoder,significantly enhancing robustness under severe occlusion(50%joint invisibility).On the Human3.6M dataset,the proposed method achieves an MPJPE of 56.21 mm under Protocol 1,outperforming the state-of-the-art baseline MHFormer by 3.3%.Extensive ablation studies on Human3.6M demonstrate the individual contributions of the core modules:the spatiotemporal dependency module and noise-suppressed multi-scale temporal module reduce MPJPE by 0.30 and 0.34 mm,respectively,while the multimodal training strategy further decreases MPJPE by 0.6 mm through text-skeleton contrastive learning.Comparative experiments involving 16 athletes show that the sagittal plane coupling angle measurements of hip-ankle joints differ by less than 1.2°from those obtained via traditional optical systems(two one-sided t-tests,p<0.05),validating real-world reliability.This study provides an AI-powered analytical solution for competitive sports training,serving as a viable alternative to specialized equipment. 展开更多
关键词 Graph convolutional networks lower limb coordination quantification 3D pose estimation
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Towards Secure APIs:A Survey on RESTful API Vulnerability Detection
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作者 Fatima Tanveer Faisal Iradat +1 位作者 Waseem Iqbal Awais Ahmad 《Computers, Materials & Continua》 2025年第9期4223-4257,共35页
RESTful APIs have been adopted as the standard way of developing web services,allowing for smooth communication between clients and servers.Their simplicity,scalability,and compatibility have made them crucial to mode... RESTful APIs have been adopted as the standard way of developing web services,allowing for smooth communication between clients and servers.Their simplicity,scalability,and compatibility have made them crucial to modern web environments.However,the increased adoption of RESTful APIs has simultaneously exposed these interfaces to significant security threats that jeopardize the availability,confidentiality,and integrity of web services.This survey focuses exclusively on RESTful APIs,providing an in-depth perspective distinct from studies addressing other API types such as GraphQL or SOAP.We highlight concrete threats-such as injection attacks and insecure direct object references(IDOR)-to illustrate the evolving risk landscape.Our work systematically reviews state-of-the-art detection methods,including static code analysis and penetration testing,and proposes a novel taxonomy that categorizes vulnerabilities such as authentication and authorization issues.Unlike existing taxonomies focused on general web or network-level threats,our taxonomy emphasizes API-specific design flaws and operational dependencies,offering a more granular and actionable framework for RESTful API security.By critically assessing current detection methodologies and identifying key research gaps,we offer a structured framework that advances the understanding and mitigation of RESTful API vulnerabilities.Ultimately,this work aims to drive significant advancements in API security,thereby enhancing the resilience of web services against evolving cyber threats. 展开更多
关键词 RESTful API vulnerability detection API security TAXONOMY systematic review
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Lithospheric Structures and Its Relationship with Seismic and Volcanic Activities:A Review of the Tonga-Kermadec Subduction Zone in the Southwestern Pacific
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作者 XIANG Dan LIANG Naiyao +3 位作者 LING Jing LI Jianxin QU Qiang ZHONG Junliu 《Journal of Ocean University of China》 2025年第3期631-646,共16页
Situated in the southwestern Pacific,the Tonga-Kermadec subduction zone is separated into two parts by the Louisvlle Ridge Seamount Chain(LRSC),i.e.,the Tanga subduction zone and the Kermadec subduction zone.Known for... Situated in the southwestern Pacific,the Tonga-Kermadec subduction zone is separated into two parts by the Louisvlle Ridge Seamount Chain(LRSC),i.e.,the Tanga subduction zone and the Kermadec subduction zone.Known for its vigorous volcanic activity,frequent large earthquakes,rapid plate subduction,and distinctive subducting plate morphology,this subduction zone provides valuable insights into its structures,dynamics,and associated geohazards.This study compiles geological and geophysical datasets in this region,including seismicity,focal mechanisms,seismic reflection and refraction profiles,and seismic tomography,to understand the relationship between lithospheric structures of the subduction system and associated seismicity-volcanic activities.Our analysis suggests that variations in overlying sediment thickness,subduction rate,and subduction angle significantly influence the lithospheric deformation processes within the Tonga-Kermadec subduction system.Furthermore,these factors contribute to the notable differences in seismicity and volcanism observed between the Tonga subduction zone and the Kermadec subduction zone.This study enhances our understanding of plate tectonics by providing insights into the interplay between subduction dynamics and lithospheric deformation,which are crucial for analyzing geological and geophysical behaviors in similar subduction environments. 展开更多
关键词 Tonga-Kermadec subduction zone lithospheric structures SEISMIC volcanic activities
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Advances in RNA contact prediction:a benchmark evaluation of computational methods
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作者 Ya-Lan Tan Cheng Guo +2 位作者 Jun-Jie Xu Ya-Zhou Shi Zhi-Jie Tan 《Communications in Theoretical Physics》 2025年第12期152-166,共15页
Ribonucleic Acid(RNA)contact prediction holds great significance for modeling RNA 3D structures and further understanding RNA biological functions.The rapid growth of RNA sequencing data has driven the development of ... Ribonucleic Acid(RNA)contact prediction holds great significance for modeling RNA 3D structures and further understanding RNA biological functions.The rapid growth of RNA sequencing data has driven the development of diverse computational methods for RNA contact prediction,and a benchmark evaluation of these methods remains essential.In this work,we first classified RNA contact prediction methods into statistical inference-based and neural networkbased ones.We then evaluated eight state-of-the-art methods on three test sets:a sequencediverse set,a structurally non-redundant set and a CASP RNA targets set.Our evaluation shows that for identifying non-local and long-range contacts,neural network-based methods outperform statistical inference-based ones,with SPOT-RNA-2D achieving the best performance,followed by CoCoNet and RNAcontact.However,for identifying the long-range tertiary contacts,which are vital for stabilizing RNA tertiary structure,statistical inference-based methods exhibit superior performance with GREMLIN emerging as the top performer.This work provides a comprehensive benchmarking of RNA contact prediction methods,highlighting their strengths and limitations to guide further methodological improvements and applications in RNA structure modeling. 展开更多
关键词 RNA contact prediction neural network-based methods statistical inference-based methods long-range tertiary contacts
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Efficient Bit-Plane Based Medical Image Cryptosystem Using Novel and Robust Sine-Cosine Chaotic Map
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作者 Zeric Tabekoueng Njitacke Louai A.Maghrabi +1 位作者 Musheer Ahmad Turki Althaqafi 《Computers, Materials & Continua》 2025年第4期917-933,共17页
This paper presents a high-security medical image encryption method that leverages a novel and robust sine-cosine map.The map demonstrates remarkable chaotic dynamics over a wide range of parameters.We employ nonlinea... This paper presents a high-security medical image encryption method that leverages a novel and robust sine-cosine map.The map demonstrates remarkable chaotic dynamics over a wide range of parameters.We employ nonlinear analytical tools to thoroughly investigate the dynamics of the chaotic map,which allows us to select optimal parameter configurations for the encryption process.Our findings indicate that the proposed sine-cosine map is capable of generating a rich variety of chaotic attractors,an essential characteristic for effective encryption.The encryption technique is based on bit-plane decomposition,wherein a plain image is divided into distinct bit planes.These planes are organized into two matrices:one containing the most significant bit planes and the other housing the least significant ones.The subsequent phases of chaotic confusion and diffusion utilize these matrices to enhance security.An auxiliary matrix is then generated,comprising the combined bit planes that yield the final encrypted image.Experimental results demonstrate that our proposed technique achieves a commendable level of security for safeguarding sensitive patient information in medical images.As a result,image quality is evaluated using the Structural Similarity Index(SSIM),yielding values close to zero for encrypted images and approaching one for decrypted images.Additionally,the entropy values of the encrypted images are near 8,with a Number of Pixel Change Rate(NPCR)and Unified Average Change Intensity(UACI)exceeding 99.50%and 33%,respectively.Furthermore,quantitative assessments of occlusion attacks,along with comparisons to leading algorithms,validate the integrity and efficacy of our medical image encryption approach. 展开更多
关键词 Image cryptosystem robust chaos sine-cosine map nonlinear analysis tools medical images
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A Federated Learning Approach for Cardiovascular Health Analysis and Detection
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作者 Farhan Sarwar Muhammad Shoaib Farooq +2 位作者 Nagwan Abdel Samee Mona M.Jamjoom Imran Ashraf 《Computers, Materials & Continua》 2025年第9期5897-5914,共18页
Environmental transition can potentially influence cardiovascular health.Investigating the relationship between such transition and heart disease has important applications.This study uses federated learning(FL)in thi... Environmental transition can potentially influence cardiovascular health.Investigating the relationship between such transition and heart disease has important applications.This study uses federated learning(FL)in this context and investigates the link between climate change and heart disease.The dataset containing environmental,meteorological,and health-related factors like blood sugar,cholesterol,maximum heart rate,fasting ECG,etc.,is used with machine learning models to identify hidden patterns and relationships.Algorithms such as federated learning,XGBoost,random forest,support vector classifier,extra tree classifier,k-nearest neighbor,and logistic regression are used.A framework for diagnosing heart disease is designed using FL along with other models.Experiments involve discriminating healthy subjects from those who are heart patients and obtain an accuracy of 94.03%.The proposed FL-based framework proves to be superior to existing techniques in terms of usability,dependability,and accuracy.This study paves the way for screening people for early heart disease detection and continuous monitoring in telemedicine and remote care.Personalized treatment can also be planned with customized therapies. 展开更多
关键词 Heart disease prediction medical data federated learning machine learning
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Zero Trust Networks: Evolution and Application from Concept to Practice
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作者 Yongjun Ren Zhiming Wang +3 位作者 Pradip Kumar Sharma Fayez Alqahtani Amr Tolba Jin Wang 《Computers, Materials & Continua》 2025年第2期1593-1613,共21页
In the context of an increasingly severe cybersecurity landscape and the growing complexity of offensive and defen-sive techniques,Zero Trust Networks(ZTN)have emerged as a widely recognized technology.Zero Trust not ... In the context of an increasingly severe cybersecurity landscape and the growing complexity of offensive and defen-sive techniques,Zero Trust Networks(ZTN)have emerged as a widely recognized technology.Zero Trust not only addresses the shortcomings of traditional perimeter security models but also consistently follows the fundamental principle of“never trust,always verify.”Initially proposed by John Cortez in 2010 and subsequently promoted by Google,the Zero Trust model has become a key approach to addressing the ever-growing security threats in complex network environments.This paper systematically compares the current mainstream cybersecurity models,thoroughly explores the advantages and limitations of the Zero Trust model,and provides an in-depth review of its components and key technologies.Additionally,it analyzes the latest research achievements in the application of Zero Trust technology across various fields,including network security,6G networks,the Internet of Things(IoT),and cloud computing,in the context of specific use cases.The paper also discusses the innovative contributions of the Zero Trust model in these fields,the challenges it faces,and proposes corresponding solutions and future research directions. 展开更多
关键词 Zero trust CYBERSECURITY software-defined perimeter micro-segmentation internet of things
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A Convolutional Neural Network Based Optical Character Recognition for Purely Handwritten Characters and Digits
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作者 Syed Atir Raza Muhammad Shoaib Farooq +3 位作者 Uzma Farooq Hanen Karamti Tahir Khurshaid Imran Ashraf 《Computers, Materials & Continua》 2025年第8期3149-3173,共25页
Urdu,a prominent subcontinental language,serves as a versatile means of communication.However,its handwritten expressions present challenges for optical character recognition(OCR).While various OCR techniques have bee... Urdu,a prominent subcontinental language,serves as a versatile means of communication.However,its handwritten expressions present challenges for optical character recognition(OCR).While various OCR techniques have been proposed,most of them focus on recognizing printed Urdu characters and digits.To the best of our knowledge,very little research has focused solely on Urdu pure handwriting recognition,and the results of such proposed methods are often inadequate.In this study,we introduce a novel approach to recognizing Urdu pure handwritten digits and characters using Convolutional Neural Networks(CNN).Our proposed method utilizes convolutional layers to extract important features from input images and classifies them using fully connected layers,enabling efficient and accurate detection of Urdu handwritten digits and characters.We implemented the proposed technique on a large publicly available dataset of Urdu handwritten digits and characters.The findings demonstrate that the CNN model achieves an accuracy of 98.30%and an F1 score of 88.6%,indicating its effectiveness in detecting and classifyingUrdu handwritten digits and characters.These results have far-reaching implications for various applications,including document analysis,text recognition,and language understanding,which have previously been unexplored in the context of Urdu handwriting data.This work lays a solid foundation for future research and development in Urdu language detection and processing,opening up new opportunities for advancement in this field. 展开更多
关键词 Image processing natural language processing handwritten Urdu characters optical character recognition deep learning feature extraction CLASSIFICATION
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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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基于R-Tree的高效异常轨迹检测算法 被引量:16
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作者 刘良旭 乔少杰 +2 位作者 刘宾 乐嘉锦 唐常杰 《软件学报》 EI CSCD 北大核心 2009年第9期2426-2435,共10页
提出了异常轨迹检测算法,通过检测轨迹的局部异常程度来判断两条轨迹是否全局匹配,进而检测异常轨迹.算法要点如下:(1)为了有效地表示轨迹的局部特征,以k个连续轨迹点作为基本比较单元,提出一种计算两个基本比较单元间不匹配程度的距离... 提出了异常轨迹检测算法,通过检测轨迹的局部异常程度来判断两条轨迹是否全局匹配,进而检测异常轨迹.算法要点如下:(1)为了有效地表示轨迹的局部特征,以k个连续轨迹点作为基本比较单元,提出一种计算两个基本比较单元间不匹配程度的距离函数,并在此基础上定义了局部匹配、全局匹配和异常轨迹的概念;(2)针对异常轨迹检测算法普遍存在计算代价高的不足,提出了一种基于R-Tree的异常轨迹检测算法,其优势在于利用R-Tree和轨迹间的距离特征矩阵找出所有可能匹配的基本比较单元对,然后再通过计算距离确定其是否局部匹配,从而消除大量不必要的距离计算.实验结果表明,该算法不仅具有很好的效率,而且检测出来的异常轨迹也具有实际意义. 展开更多
关键词 异常轨迹检测 R树 基于平移的最小Hausdorff距离 全局匹配 局部匹配
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面向随机模型检验的模型抽象技术 被引量:2
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作者 刘阳 李宣东 马艳 《软件学报》 EI CSCD 北大核心 2015年第8期1853-1870,共18页
随机模型检验是经典模型检验理论的延伸和推广,由于其结合了经典模型检验算法和线性方程组求解或线性规划算法等,并且运算处理的是关于状态的概率向量而非经典模型检验中的位向量,所以状态爆炸问题在随机模型检验中更为严重.抽象作为缓... 随机模型检验是经典模型检验理论的延伸和推广,由于其结合了经典模型检验算法和线性方程组求解或线性规划算法等,并且运算处理的是关于状态的概率向量而非经典模型检验中的位向量,所以状态爆炸问题在随机模型检验中更为严重.抽象作为缓解状态空间爆炸问题的重要技术之一,已经开始被应用到随机模型检验领域并取得了一定的进展.以面向随机模型检验的模型抽象技术为研究对象,首先给出了模型抽象技术的问题描述,然后按抽象模型构造技术分类归纳了其研究方向及目前的研究进展,最后对比了目前的模型抽象技术及其关系,总结出其还未能给出模型抽象问题的满意答案,并指出了有效解决模型抽象问题未来的研究方向. 展开更多
关键词 随机模型检验 状态空间爆炸 模型抽象 定量抽象精化
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A Scalable Adaptive Approach to Multi-Vehicle Formation Control with Obstacle Avoidance 被引量:11
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作者 Xiaohua Ge Qing-Long Han +1 位作者 Jun Wang Xian-Ming Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第6期990-1004,共15页
This paper deals with the problem of distributed formation tracking control and obstacle avoidance of multivehicle systems(MVSs)in complex obstacle-laden environments.The MVS under consideration consists of a leader v... This paper deals with the problem of distributed formation tracking control and obstacle avoidance of multivehicle systems(MVSs)in complex obstacle-laden environments.The MVS under consideration consists of a leader vehicle with an unknown control input and a group of follower vehicles,connected via a directed interaction topology,subject to simultaneous unknown heterogeneous nonlinearities and external disturbances.The central aim is to achieve effective and collisionfree formation tracking control for the nonlinear and uncertain MVS with obstacles encountered in formation maneuvering,while not demanding global information of the interaction topology.Toward this goal,a radial basis function neural network is used to model the unknown nonlinearity of vehicle dynamics in each vehicle and repulsive potentials are employed for obstacle avoidance.Furthermore,a scalable distributed adaptive formation tracking control protocol with a built-in obstacle avoidance mechanism is developed.It is proved that,with the proposed protocol,the resulting formation tracking errors are uniformly ultimately bounded and obstacle collision avoidance is guaranteed.Comprehensive simulation results are elaborated to substantiate the effectiveness and the promising collision avoidance performance of the proposed scalable adaptive formation control approach. 展开更多
关键词 Adaptive control collision avoidance distributed formation control multi-vehicle systems neural networks obstacle avoidance repulsive potential
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应用纹理三角条形以改进真实感图形绘制性能(英文) 被引量:2
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作者 杨宇 Tulika Mitra 黄智勇 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2004年第6期740-746,共7页
改进真实感图形绘制性能是计算机图形系统的一个基本问题 文中探讨了一些几何压缩算法对真实感图形绘制性能的影响 ,这些算法是为了优化使用形体顶点高速缓冲存储器而设计的 ;研究了这些算法和计算机芯片上纹理高速缓冲存储器的相互作... 改进真实感图形绘制性能是计算机图形系统的一个基本问题 文中探讨了一些几何压缩算法对真实感图形绘制性能的影响 ,这些算法是为了优化使用形体顶点高速缓冲存储器而设计的 ;研究了这些算法和计算机芯片上纹理高速缓冲存储器的相互作用 ;提出了一个基于三角条形的简单方法 ,以通过平衡使用形体顶点和纹理高速缓冲存储器而改进真实感图形绘制性能 最后 。 展开更多
关键词 真实感图形绘制性能 几何压缩 纹理映射 高速缓冲存储
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Multifunctional inverse sensing by spatial distribution characterization of scattering photons 被引量:6
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作者 Lianwei Chen Yumeng Yin +1 位作者 Yang Li Minghui Hong 《Opto-Electronic Advances》 2019年第9期15-22,共8页
Inverse sensing is an important research direction to provide new perspectives for optical sensing. For inverse sensing, the primary challenge is that scattered photon has a complicated profile, which is hard to deriv... Inverse sensing is an important research direction to provide new perspectives for optical sensing. For inverse sensing, the primary challenge is that scattered photon has a complicated profile, which is hard to derive a general solution. Instead of a general solution, it is more feasible and practical to derive a solution based on a specific environment. With deep learning, we develop a multifunctional inverse sensing approach for a specific environment. This inverse sensing approach can reconstruct the information of scattered photons and characterize multiple optical parameters simultaneously. Its functionality can be upgraded dynamically after learning more data. It has wide measurement range and can characterize the optical signals behind obstructions. The high anti-noise performance, flexible implementation, and extremely high threshold to optical damage or saturation make it useful for a wide range of applications, including self-driving car, space technology, data security, biological characterization, and integrated photonics. 展开更多
关键词 deep learning optical SENSING PHOTONICS
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An efficient method for tracing planar implicit curves 被引量:2
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作者 YU Zheng-sheng CAI Yao-zhi +2 位作者 OH Min-jae KIM Tae-wan PENG Qun-sheng 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第7期1115-1123,共9页
This paper presents a method for tracing a planar implicit curve f(x, y)=0 on a rectangular region based on continuation scheme. First, according to the starting track-point and the starting track-direction of the c... This paper presents a method for tracing a planar implicit curve f(x, y)=0 on a rectangular region based on continuation scheme. First, according to the starting track-point and the starting track-direction of the curve, make a new fimction F(x, y)=0 where the same curve withf(x, y)=0 is defined. Then we trace the curve between the two domains where F(x, y)〉0 and F(x, y)〈0 alternately, according to the two rules presented in this paper. Equal step size or adaptive step size can be used, when we trace the curve. An irregular planar implicit curve (such as the curve with large curvatures at some points on the curve), can be plotted if an adaptive step size is used. Moreover, this paper presents a scheme to search for the multiple points on the curve. Our method has the following advantages: (1) it can plot Co planar implicit curves; (2) it can plot the planar implicit curves with multiple points; (3) by the help of using the two rules, our method does not need to compute the tangent vector at the points on the curve, and directly searches for the direction of the tracing curve; (4) the tracing procedure costs only one of two evaluations of function f(x, y)=0 per moving step, while most existing similar methods cost more evaluations of the function. 展开更多
关键词 Planar implicit curve Curve tracing Continuation method Geometric modeling
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