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Multi-wavelength pulses in synchronized mode-locked fiber lasers
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作者 WU Qiong GAO Bo +8 位作者 ZHOU Lu-yao WEN Hong-lin QIAO Fei-hong WU Bing XU Ting LI Qi LI Ying-ying WU Ge LIU Lie 《中国光学(中英文)》 北大核心 2026年第2期445-453,共9页
We designed and investigated a passive synchronized mode-locked fiber laser.The device utilizes a dual-cavity structure driven by the nonlinear polarization rotation(NPR)mechanism.Stable mode-locking is attained by sy... We designed and investigated a passive synchronized mode-locked fiber laser.The device utilizes a dual-cavity structure driven by the nonlinear polarization rotation(NPR)mechanism.Stable mode-locking is attained by synergistically controlling gain,polarization state,and optical path length in two symmetric sub-cavities.Experiments proved that repetition rate of the sub-cavities can be adjusted via the time delay line(TDL)to achieve synchronized mode-locking.The system stably generates multi-wavelength pulses at a single repetition frequency,evidenced by multiple spectral peaks and equidistant pulse sequences.These findings facilitate the development of high-performance multi-wavelength ultrashort pulse sources,crucial for optical communications,spectral analysis,and remote sensing. 展开更多
关键词 synchronized mode-locked fiber laser multi-wavelength pulses dual-cavity
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Joint Optimization of Routing and Resource Allocation in Decentralized UAV Networks Based on DDQN and GNN
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作者 Nawaf Q.H.Othman YANG Qinghai JIANG Xinpei 《电讯技术》 北大核心 2026年第1期1-10,共10页
Optimizing routing and resource allocation in decentralized unmanned aerial vehicle(UAV)networks remains challenging due to interference and rapidly changing topologies.The authors introduce a novel framework combinin... Optimizing routing and resource allocation in decentralized unmanned aerial vehicle(UAV)networks remains challenging due to interference and rapidly changing topologies.The authors introduce a novel framework combining double deep Q-networks(DDQNs)and graph neural networks(GNNs)for joint routing and resource allocation.The framework uses GNNs to model the network topology and DDQNs to adaptively control routing and resource allocation,addressing interference and improving network performance.Simulation results show that the proposed approach outperforms traditional methods such as Closest-to-Destination(c2Dst),Max-SINR(mSINR),and Multi-Layer Perceptron(MLP)-based models,achieving approximately 23.5% improvement in throughput,50% increase in connection probability,and 17.6% reduction in number of hops,demonstrating its effectiveness in dynamic UAV networks. 展开更多
关键词 decentralized UAV network resource allocation routing algorithm GNN DDQN DRL
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Flexible and Stable Quantum Dot-PDMS Films via Screen Printing for Photonic Anti-counterfeiting
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作者 LIU Xing HUANG Min +4 位作者 LI Xiu WANG Qiang ZHANG Yuan-kun LI Gen YANG Li-xue 《印刷与数字媒体技术研究》 北大核心 2026年第1期138-146,共9页
Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in ... Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in scalable flexible fabrication.In this study,a high-stability fluorescent ink was developed by incorporating QDs into a polydimethylsiloxane(PDMS)colloidal matrix.High-performance patterned films were then obtained via systematic optimization of screen-printing parameters,with film quality governed by substrate type(131μm PDMS),QD concentration(1.5 mg/mL),and screen mesh count(420 mesh).The optimized films exhibit outstanding environmental and photostability,retaining 75.6% of their fluorescence intensity after immersion in deionized water and 63.8% in 75%ethanol at 25℃ for 100 minutes.Under UV irradiation(365 nm,9 W,100 min),fluorescence intensity decreases by less than 20%.Utilizing their daylight transparency and UV-excitable luminescence,various patterns including QR codes and Code 93 standard barcodes were fabricated via screen printing with high pattern fidelity and machine readability.This study presents a scalable and reliable strategy for the fabrication of flexible,high-stability fluorescent films,supporting their integration into next-generation optoelectronic devices,advanced displays,and secure anti-counterfeiting. 展开更多
关键词 Quantum dots Screen printing FLEXIBILITY Optical anti-counterfeiting
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Precise calibration of liquid crystal variable retarder for various incident angles
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作者 KONG Quan-hui-zi ZHANG Rui +2 位作者 XUE Peng WANG Zhi-bin JING Ning 《中国光学(中英文)》 北大核心 2026年第2期434-444,共11页
This study investigates the reduction in polarization measurement accuracy caused by varying in-cident angles in a liquid crystal variable retarder(LCVR).The phase delay characteristics of the LCVR were examined,with ... This study investigates the reduction in polarization measurement accuracy caused by varying in-cident angles in a liquid crystal variable retarder(LCVR).The phase delay characteristics of the LCVR were examined,with particular emphasis on the influence of different two-dimensional incident angles on phase delay behavior.Building upon the calibration of phase delay under normal incidence,a phase delay calibra-tion model was developed to account for variations in incident angle and driving voltage.A mathematical re-lationship was established between phase delay and the azimuth angle(α)and pitch angle(β).Experimental validation was conducted under three conditions:α=20°,β=0°;α=0°,β=20°;and an arbitrary angle whereα=5°,β=15°.The results demonstrated that the maximum average deviation between theoretical pre-dictions and experimental measurements did not exceed 0.059 rad.The proposed calibration method proved to be both accurate and practical.This approach offers robust support for LCVR parameter calibration and performance optimization in optical systems,particularly in polarization imaging applications. 展开更多
关键词 liquid crystal variable retarder(LCVR) two-dimensional incident angles drive voltage phase delay calibration
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Aligning with Global Rules The Hainan FTP is China's new model for institutional opening-up
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作者 Yu Yunquan 《China Report ASEAN》 2026年第3期24-25,共2页
The Hainan Free Trade Port (FTP) is a key step for China to advance high-standard opening-up and seize a more active role in economic globalization. After early trials, a policy framework has taken shape, and islandwi... The Hainan Free Trade Port (FTP) is a key step for China to advance high-standard opening-up and seize a more active role in economic globalization. After early trials, a policy framework has taken shape, and islandwide special customs operations mark a shift from design to full implementation.As of January 18, island-wide special customs operations in Hainan FTP had been in place for a month. The first month ran smoothly, with more efficient flow of goods, people, and capital.This reflects China’s institutional opening-up and, amid slowing global growth, has injected fresh vitality into the regional and global economy. 展开更多
关键词 free trade port Special Customs Operations economic globalization policy framework Hainan Free Trade Port Institutional Opening up customs operations Regional Economy
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A Gateway for Opening Up
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作者 YU YUNQUAN 《ChinAfrica》 2026年第3期34-35,共2页
Hainan FTP will boost alignment with international rules in China’s opening up The Hainan Free Trade Port(FTP)represents a significant step forward in China’s pursuit of high-standard opening up and greater engageme... Hainan FTP will boost alignment with international rules in China’s opening up The Hainan Free Trade Port(FTP)represents a significant step forward in China’s pursuit of high-standard opening up and greater engagement in economic globalisation.Following years of exploration,the policy framework for the Hainan FTP has come into being,and the recent launch of island-wide special customs operations marks an important transition-from institutional design to full implementation. 展开更多
关键词 Special Customs Operations International Rules policy framework Hainan Free Trade Port free trade port ftp represents alignment international rules institutional design Opening Up
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Hainan FTP:A New Step to Align with International Rules in Opening-Up
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作者 YU YUNQUAN 《China Today》 2026年第3期32-33,共2页
The Hainan Free Trade Port’s implementation of special customs operations marks a significant stride in China’s institutional opening-up,spurring global trade and investment flows.THE Hainan Free Trade Port(FTP)repr... The Hainan Free Trade Port’s implementation of special customs operations marks a significant stride in China’s institutional opening-up,spurring global trade and investment flows.THE Hainan Free Trade Port(FTP)represents a significant step forward in China’s pursuit of high-standard opening-up and greater engagement in economic globalization. 展开更多
关键词 implementation special customs operations Special Customs Operations free trade port's Global Trade Hainan Free Trade Port free trade port ftp represents Institutional Opening Up Investment Flows
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The intelligent leap of wireless short-range connection
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作者 Wan Lei 《China Standardization》 2026年第1期47-47,共1页
Founded in September 2020,the International SparkLink Alliance(iSLA)now has approximately 1,200 members in diverse sectors including terminals,homes,vehicles,manufacturing,transportation,finance and healthcare.The iSL... Founded in September 2020,the International SparkLink Alliance(iSLA)now has approximately 1,200 members in diverse sectors including terminals,homes,vehicles,manufacturing,transportation,finance and healthcare.The iSLA has established a technical standards system for wireless short-range communication covering full-stack standards such as the end-to-end protocol system. 展开更多
关键词 wireless short range communication end end protocol system technical standards system full stack standards international sparklink alliance isla now wireless short range connection standards system ISLA
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Connecting Hearts,Not Just Dots A Lao language editor's perspective on China-Laos relations
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作者 Yang Chunmei 《China Report ASEAN》 2026年第1期41-43,共3页
As an ordinary Yunnan local,I never imagined becoming so closely connected to the exotic land of Laos.The luckiest event of my life was probably my choice to tick a box on a 2007 college entrance examination applicati... As an ordinary Yunnan local,I never imagined becoming so closely connected to the exotic land of Laos.The luckiest event of my life was probably my choice to tick a box on a 2007 college entrance examination application form,indicating my willingness to enrollin a major other than my preference,which led me into the world of the Lao language. 展开更多
关键词 education China language learning personal experience RELATIONS lao language Laos
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TP-ViT:truncated uniform-log2 quantizer and progressive bit-decline reconstruction for vision Transformer quantization
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作者 Xichuan ZHOU Sihuan ZHAO +4 位作者 Rui DING Jiayu SHI Jing NIE Lihui CHEN Haijun LIU 《ENGINEERING Information Technology & Electronic Engineering》 2026年第1期47-58,共12页
Vision Transformers(ViTs)have achieved remarkable success across various artificial intelligence-based computer vision applications.However,their demanding computational and memory requirements pose significant challe... Vision Transformers(ViTs)have achieved remarkable success across various artificial intelligence-based computer vision applications.However,their demanding computational and memory requirements pose significant challenges for de-ployment on resource-constrained edge devices.Although post-training quantization(PTQ)provides a promising solution by reducing model precision with minimal calibration data,aggressive low-bit quantization typically leads to substantial perfor-mance degradation.To address this challenge,we present the truncated uniform-log2 quantizer and progressive bit-decline reconstruction method for vision Transformer quantization(TP-ViT).It is an innovative PTQ framework specifically designed for ViTs,featuring two key technical contributions:(1)truncated uniform-log2 quantizer,a novel quantization approach which effectively handles outlier values in post-Softmax activations,significantly reducing quantization errors;(2)bit-decline optimiza-tion strategy,which employs transition weights to gradually reduce bit precision while maintaining model performance under extreme quantization conditions.Comprehensive experiments on image classification,object detection,and instance segmenta-tion tasks demonstrate TP-ViT’s superior performance compared to state-of-the-art PTQ methods,particularly in challenging 3-bit quantization scenarios.Our framework achieves a notable 6.18 percentage points improvement in top-1 accuracy for ViT-small under 3-bit quantization.These results validate TP-ViT’s robustness and general applicability,paving the way for more efficient deployment of ViT models in computer vision applications on edge hardware. 展开更多
关键词 Vision Transformers Post-training quantization Block reconstruction Image classification Object detection Instance segmentation
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Design and Validation of Zeroing Neural Network With Active Noise Rejection Capability for Time-Varying Problems Solving
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作者 Yilin Shang Wenbo Zhang +1 位作者 Dongsheng Guo Shan Xue 《CAAI Transactions on Intelligence Technology》 2026年第1期256-266,共11页
Recently,the zeroing neural network(ZNN)has demonstrated remarkable effectiveness in tackling time-varying problems,delivering robust performance across both noise-free and noisy environments.However,existing ZNN mode... Recently,the zeroing neural network(ZNN)has demonstrated remarkable effectiveness in tackling time-varying problems,delivering robust performance across both noise-free and noisy environments.However,existing ZNN models are limited in their ability to actively suppress noise,which constrains their robustness and precision in solving time-varying problems.This paper introduces a novel active noise rejection ZNN(ANR-ZNN)design that enhances noise suppression by integrating computational error dynamics and harmonic behaviour.Through rigorous theoretical analysis,we demonstrate that the proposed ANR-ZNN maintains robust convergence in computational error performance under environmental noise.As a case study,the ANR-ZNN model is specifically applied to time-varying matrix inversion.Comprehensive computer simulations and robotic experiments further validate the ANR-ZNN's effectiveness,emphasising the proposed design's superiority and potential for solving time-varying problems. 展开更多
关键词 active noise rejection matrix inversion robot application time-varying problems zeroing neural network
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EB-Guided Optimization of Heliostat Fields with Validated Projection Losses and HFLCAL Sensitivity
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作者 Zichang Meng Na Chen +2 位作者 Qi Li Qingyi Liu Hongfei Jiang 《Energy Engineering》 2026年第4期134-153,共20页
Heliostat field design for tower solar thermal plants must jointly address solar geometry,optical losses,and layout optimization under engineering constraints.We develop an end-to-end workflow that(i)adopts a consiste... Heliostat field design for tower solar thermal plants must jointly address solar geometry,optical losses,and layout optimization under engineering constraints.We develop an end-to-end workflow that(i)adopts a consistent East–North–Up(ENU)convention for all plant-and sun-related vectors;(ii)integrates cosine efficiency,projection-based shading and blocking(SB),atmospheric transmittance,and an HFLCAL(heliostat field local calculation)truncation model into a single optical chain;and(iii)couples an Eliminate-Blocking(EB)layout prior with an improved“Cheetah”metaheuristic to search ring topology,mirror sizes,and heights while enforcing spacing,kinematics,and rated-power requirements.Projection-based SB is calibrated against Monte-Carlo ray tracing at representative sun positions,and the HFLCAL truncation model is used to quantify sensitivities to sunshape and error-budget parameters.In a three-phase study(fixed-size baseline,uniform sizing,heterogeneous sizing),the EB-guided optimizer improves annual per-area output relative to a radial baseline and reliably attains a 60 MW target.Under equal evaluation budgets,the proposed optimizer converges faster and with lower variance than GA-and PSO-based baselines,while respecting panel-level peak-flux limits through a smooth penalization of flux violations.The resulting layouts exhibit outward-increasing azimuthal spacing and ring-wise size sharing that are consistent with recent heliostat-field deployment experience.The framework is modular,auditable,and readily adaptable to alternative receivers,sites,and cost-aware objectives. 展开更多
关键词 Heliostat field shading and blocking HFLCAL truncation eliminate-blocking layout metaheuristics solar tower sensitivity analysis
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Research on Beam Peak Search Reduction for 5G mm-Wave OTA Testing
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作者 An Xudong Yin Mengru +2 位作者 Li Wenyu Qu Meijun Sun Siyang 《China Communications》 2026年第1期1-9,共9页
For 5G millimeter wave(mm-Wave)user equipments(UEs),all test cases must be evaluated in Over-The-Air(OTA)manner.Test time increases dramatically compared to Sub-6 GHz.Therefore,test time reduction is of great signific... For 5G millimeter wave(mm-Wave)user equipments(UEs),all test cases must be evaluated in Over-The-Air(OTA)manner.Test time increases dramatically compared to Sub-6 GHz.Therefore,test time reduction is of great significance for 5G mm-Wave OTA testing.Among all test cases,beam peak search is the most time-consuming,taking up the majority of the overall test time.Therefore,the objective of this work is to determine a suitable beam peak search grid for 5G mm-Wave UEs with satisfactory accuracy and efficiency.Through radiation property investigation of 5G mm-Wave commercial UEs,more reasonable reference array configuration(4×2)and reference deployment scenario(composite beam)are proposed for beam peak search grid analysis.The effect of different grid configurations on beam peak search precision are characterized quantitatively.The determination of associated measurement uncertainty(MU)term along with quantitative analysis approach are proposed based on statistical analysis.Finally,the recommended minimum number of beam peak search grid points is 182 based on the proposed 4×2 array under composite beam scenario.Compared with currently-required 1106 points in 3GPP/CTIA specifications,over 80%reduction can be achieved without increasing the MU limit.The feasibility of the proposed MU analysis as well as the recommended grids is demonstrated through measurements. 展开更多
关键词 beam peak search composite beam 5G mm-Wave measurement grid MU OTA
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A Novel Unified Framework for Automated Generation and Multimodal Validation of UML Diagrams
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作者 Van-Viet Nguyen Huu-Khanh Nguyen +4 位作者 Kim-Son Nguyen Thi Minh-Hue Luong Duc-Quang Vu Trung-Nghia Phung The-Vinh Nguyen 《Computer Modeling in Engineering & Sciences》 2026年第1期1023-1050,共28页
It remains difficult to automate the creation and validation of Unified Modeling Language(UML)dia-grams due to unstructured requirements,limited automated pipelines,and the lack of reliable evaluation methods.This stu... It remains difficult to automate the creation and validation of Unified Modeling Language(UML)dia-grams due to unstructured requirements,limited automated pipelines,and the lack of reliable evaluation methods.This study introduces a cohesive architecture that amalgamates requirement development,UML synthesis,and multimodal validation.First,LLaMA-3.2-1B-Instruct was utilized to generate user-focused requirements.Then,DeepSeek-R1-Distill-Qwen-32B applies its reasoning skills to transform these requirements into PlantUML code.Using this dual-LLM pipeline,we constructed a synthetic dataset of 11,997 UML diagrams spanning six major diagram families.Rendering analysis showed that 89.5%of the generated diagrams compile correctly,while invalid cases were detected automatically.To assess quality,we employed a multimodal scoring method that combines Qwen2.5-VL-3B,LLaMA-3.2-11B-Vision-Instruct and Aya-Vision-8B,with weights based on MMMU performance.A study with 94 experts revealed strong alignment between automatic and manual evaluations,yielding a Pearson correlation of r=0.82 and a Fleiss’Kappa of 0.78.This indicates a high degree of concordance between automated metrics and human judgment.Overall,the results demonstrated that our scoring system is effective and that the proposed generation pipeline produces UML diagrams that are both syntactically correct and semantically coherent.More broadly,the system provides a scalable and reproducible foundation for future work in AI-driven software modeling and multimodal verification. 展开更多
关键词 Automated dataset generation vision-language models multimodal validation software engineering automation UMLCode
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TopoMSG:A Topology-Aware Multi-Scale Graph Network for Social Bot Detection
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作者 Junhui Xu Qi Wang +1 位作者 Chichen Lin Weijian Fan 《Computers, Materials & Continua》 2026年第3期1164-1178,共15页
Social bots are automated programs designed to spread rumors and misinformation,posing significant threats to online security.Existing research shows that the structure of a social network significantly affects the be... Social bots are automated programs designed to spread rumors and misinformation,posing significant threats to online security.Existing research shows that the structure of a social network significantly affects the behavioral patterns of social bots:a higher number of connected components weakens their collaborative capabilities,thereby reducing their proportion within the overall network.However,current social bot detection methods still make limited use of topological features.Furthermore,both graph neural network(GNN)-based methods that rely on local features and those that leverage global features suffer from their own limitations,and existing studies lack an effective fusion of multi-scale information.To address these issues,this paper proposes a topology-aware multi-scale social bot detection method,which jointly learns local and global representations through a co-training mechanism.At the local level,topological features are effectively embedded into node representations,enhancing expressiveness while alleviating the over-smoothing problem in GNNs.At the global level,a clustering attention mechanism is introduced to learn global node representations,mitigating the over-globalization problem.Experimental results demonstrate that our method effectively overcomes the limitations of single-scale approaches.Our code is publicly available at https://anonymous.4open.science/r/TopoMSG-2C41/(accessed on 27 October 2025). 展开更多
关键词 Social bot detection graph neural network topological data analysis
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Chinese Rural Women's Social Media Use: An Empirical Study Adopting the Technology Acceptance Model
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作者 Zhang Hui Mahadevan Krishnan 《Contemporary Social Sciences》 2026年第1期104-122,共19页
Given the growing importance of social media in digital rural development, this study systematically investigated the influence pathways of social media use among rural women in China, drawing on the Technology Accept... Given the growing importance of social media in digital rural development, this study systematically investigated the influence pathways of social media use among rural women in China, drawing on the Technology Acceptance Model(TAM). Employing quantitative research methods, the study conducted empirical tests based on 367 valid questionnaires using Partial Least Squares Structural Equation Modeling(PLS-SEM) via SmartPLS 4.0 software. Results indicate that significant associations exist between perceived ease of use, perceived usefulness, attitudes toward use, behavioral intention, and actual usage behavior. Specifically, the study finds that rural women's perceived ease of use of social media has a significant and positive influence on both perceived usefulness and attitudes toward use. Perceived usefulness further significantly promotes attitudes toward use and behavioral intention. Moreover, positive attitudes toward usage and strong behavioral intentions were effectively converted into actual social media usage behaviors. This study not only validates the applicability and explanatory power of the TAM model in understanding the digital behavior of Chinese rural women but also provides quantitative evidence for how social media enhances their “digital visibility.” These findings offer practical insights for governments and platform providers to optimize user experiences and strengthen digital skills training. Despite its limitations, including a cross-sectional design and a regional sample, this research holds significant theoretical and practical implications. 展开更多
关键词 Chinese rural women social media Technology Acceptance Model(TAM) digital visibility
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Syntax-Aware Hierarchical Attention Networks for Code Vulnerability Detection
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作者 Yongbo Jiang Shengnan Huang +1 位作者 Tao Feng Baofeng Duan 《Computers, Materials & Continua》 2026年第1期2252-2273,共22页
In the context of modern software development characterized by increasing complexity and compressed development cycles,traditional static vulnerability detection methods face prominent challenges including high false ... In the context of modern software development characterized by increasing complexity and compressed development cycles,traditional static vulnerability detection methods face prominent challenges including high false positive rates and missed detections of complex logic due to their over-reliance on rule templates.This paper proposes a Syntax-Aware Hierarchical Attention Network(SAHAN)model,which achieves high-precision vulnerability detection through grammar-rule-driven multi-granularity code slicing and hierarchical semantic fusion mechanisms.The SAHAN model first generates Syntax Independent Units(SIUs),which slices the code based on Abstract Syntax Tree(AST)and predefined grammar rules,retaining vulnerability-sensitive contexts.Following this,through a hierarchical attention mechanism,the local syntax-aware layer encodes fine-grained patterns within SIUs,while the global semantic correlation layer captures vulnerability chains across SIUs,achieving synergistic modeling of syntax and semantics.Experiments show that on benchmark datasets like QEMU,SAHAN significantly improves detection performance by 4.8%to 13.1%on average compared to baseline models such as Devign and VulDeePecker. 展开更多
关键词 Vulnerability detection abstract syntax tree syntax rule slicing hierarchical attention mechanism deep learning
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Secure Rate Maximization for UAV-RIS-Aided IoT Network in Smart Grid
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作者 Jian Wu Xiaowei Hao Chao Han 《Energy Engineering》 2026年第3期215-231,共17页
Owing to the development of communication technologies and control systems,the integration of numerous Internet of Things(IoT)nodes into the power grid has become increasingly prevalent.These nodes are deployed to gat... Owing to the development of communication technologies and control systems,the integration of numerous Internet of Things(IoT)nodes into the power grid has become increasingly prevalent.These nodes are deployed to gather operational data from various distributed energy sources and monitor real-time energy consumption,thereby transforming the traditional power grid into a smart grid(SG).However,the openness of wireless communication channels introduces vulnerabilities,as it allows potential eavesdroppers to intercept sensitive information.This poses threats to the secure and efficient operation of the IoT-driven smart grid.To address these challenges,we propose a novel scenario that incorporates an Unmanned Aerial Vehicle(UAV)as a relay gateway for multiple authorized smart meters.This scenario is further enhanced by the integration of Reconfigurable Intelligent Surface(RIS)technology,which dynamically adjusts the direction of information transmission.Our objective is to maximize the secure rate within this UAV-RIS-aided system with multiple authorized smart meters and an eavesdropper based on physical layer security(PLS)techniques.We formulate the problem of secure rate maximization by jointly optimizing the active beamforming of the UAV,the passive beamforming of the RIS,and the UAV’s trajectory.To solve this complex optimization problem,we introduce the Twin Soft Actor-Critic(TSAC)algorithm.This algorithm employs a dual-agent framework,where Agent 1 focuses on optimizing the beamforming for both the UAV and the RIS,while Agent 2 concurrently searches for the optimal trajectory of the UAV.Simulation results demonstrate the TSAC algorithm significantly enhances the secure rate of the system,achieving faster convergence and higher rewards under the worst communication conditions.The TSAC algorithm consistently outperforms the Twin Deep Deterministic Policy Gradient(TDDPG)and Twin Delayed Deep Deterministic Policy Gradient(TTD3)algorithms.Furthermore,the TSAC algorithm exhibits robust performance when the distribution of smart meters follows a Gaussian distribution,further validating its practical applicability and effectiveness in real-world scenarios. 展开更多
关键词 Smart grid Internet of Things unmanned aerial vehicles reconfigurable intelligent surface EAVESDROPPER secure capacity
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Energy Efficiency and Total Mission Completion Time Tradeoff in Multiple UAVs-Mounted IRS-Assisted Data Collection System
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作者 Hong Zhao Hongbin Chen +2 位作者 Zhihui Guo Ling Zhan Shichao Li 《Computers, Materials & Continua》 2026年第2期1849-1873,共25页
UAV-mounted intelligent reflecting surface(IRS)helps address the line-of-sight(LoS)blockage between sensor nodes(SNs)and the fusion center(FC)in Internet of Things(IoT).This paper considers an IoT assisted by multiple... UAV-mounted intelligent reflecting surface(IRS)helps address the line-of-sight(LoS)blockage between sensor nodes(SNs)and the fusion center(FC)in Internet of Things(IoT).This paper considers an IoT assisted by multiple UAVs-mounted IRS(U-IRS),where the data from ground SNs are transmitted to the FC.In practice,energy efficiency(EE)and mission completion time are crucial metrics for evaluating system performance and operational costs.Recognizing their importance during data collection,we formulate a multi-objective optimization problem to maximize EE and minimize total mission completion time simultaneously.To characterize this tradeoff while considering optimization objective consistency,we construct an optimization problem that minimizes the weighted sum of the total mission completion time and the reciprocal of EE.Due to the non-convex nature of the formulated problem,obtaining optimal solutions is generally challenging.To tackle this issue,we decompose it into three subproblems:UAV-SN association,number of reflecting elements allocation,andUAVtrajectory optimization.An iterative algorithmcombining genetic algorithm,CS-BJ algorithm,and successive convex approximation technique is proposed to solve these sub-problems.Simulation results demonstrate that when the transmitted data amount is 10 and 30Mbits,compared to the static collection benchmark(the UAV hovers directly above each SN),the EE of the proposed method improves by more than 10.4% and 5.2%,while the total mission completion time is reduced by more than 5.4% and 3.3%,respectively. 展开更多
关键词 Unmanned aerial vehicle intelligent reflecting surface energy efficiency totalmission completion time optimization
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Improving Person Recognition for Single-Person-in-Photos:Intimacy in Photo Collections
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作者 Xiaoyi Duan Tianqi Zou +2 位作者 Chenyang Wang Yu Gu Xiuying Li 《Computers, Materials & Continua》 2026年第2期2089-2112,共24页
Person recognition in photo collections is a critical yet challenging task in computer vision.Previous studies have used social relationships within photo collections to address this issue.However,these methods often ... Person recognition in photo collections is a critical yet challenging task in computer vision.Previous studies have used social relationships within photo collections to address this issue.However,these methods often fail when performing single-person-in-photos recognition in photo collections,as they cannot rely on social connections for recognition.In this work,we discard social relationships and instead measure the relationships between photos to solve this problem.We designed a new model that includes a multi-parameter attention network for adaptively fusing visual features and a unified formula for measuring photo intimacy.This model effectively recognizes individuals in single photo within the collection.Due to outdated annotations and missing photos in the existing PIPA(Person in Photo Album)dataset,wemanually re-annotated it and added approximately ten thousand photos of Asian individuals to address the underrepresentation issue.Our results on the re-annotated PIPA dataset are superior to previous studies in most cases,and experiments on the supplemented dataset further demonstrate the effectiveness of our method.We have made the PIPA dataset publicly available on Zenodo,with the DOI:10.5281/zenodo.12508096(accessed on 15 October 2025). 展开更多
关键词 Deep learning computer vision person recognition photo intimacy PIPA dataset
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