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Physics and data-driven alternative optimization enabled ultra-low-sampling single-pixel imaging 被引量:1
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作者 Yifei Zhang Yingxin Li +5 位作者 Zonghao Liu Fei Wang Guohai Situ Mu Ku Chen Haoqiang Wang Zihan Geng 《Advanced Photonics Nexus》 2025年第3期55-66,共12页
Single-pixel imaging(SPI)enables efficient sensing in challenging conditions.However,the requirement for numerous samplings constrains its practicality.We address the challenge of high-quality SPI reconstruction at ul... Single-pixel imaging(SPI)enables efficient sensing in challenging conditions.However,the requirement for numerous samplings constrains its practicality.We address the challenge of high-quality SPI reconstruction at ultra-low sampling rates.We develop an alternative optimization with physics and a data-driven diffusion network(APD-Net).It features alternative optimization driven by the learned task-agnostic natural image prior and the task-specific physics prior.During the training stage,APD-Net harnesses the power of diffusion models to capture data-driven statistics of natural signals.In the inference stage,the physics prior is introduced as corrective guidance to ensure consistency between the physics imaging model and the natural image probability distribution.Through alternative optimization,APD-Net reconstructs data-efficient,high-fidelity images that are statistically and physically compliant.To accelerate reconstruction,initializing images with the inverse SPI physical model reduces the need for reconstruction inference from 100 to 30 steps.Through both numerical simulations and real prototype experiments,APD-Net achieves high-quality,full-color reconstructions of complex natural images at a low sampling rate of 1%.In addition,APD-Net’s tuning-free nature ensures robustness across various imaging setups and sampling rates.Our research offers a broadly applicable approach for various applications,including but not limited to medical imaging and industrial inspection. 展开更多
关键词 single-pixel imaging deep learning alternative optimization
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Composite scanning approach for beaconless spatial acquisition and optimized parameters under satellite platform vibrations
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作者 Shengfa LIAO Jian JIAO +2 位作者 Yaosheng ZHANG Ye WANG Qinyu ZHANG 《Chinese Journal of Aeronautics》 2025年第7期452-466,共15页
Mega Low Earth Orbit(LEO)satellite constellations can provide pervasive intelligent services in the forthcoming Six-Generation(6G)network via the Free-Space Optical(FSO)InterSatellite Link(ISL).However,the challenges ... Mega Low Earth Orbit(LEO)satellite constellations can provide pervasive intelligent services in the forthcoming Six-Generation(6G)network via the Free-Space Optical(FSO)InterSatellite Link(ISL).However,the challenges posed by the mega LEO satellite constellations,such as limited onboard resources,high-speed movement and the vibration of satellite platforms,present significant obstacles for the existing Pointing,Acquisition and Tracking(PAT)schemes of FSOISL.To address these challenges,we propose a beaconless PAT scheme under satellite platform vibrations,employing a composite scanning approach combining an inner Archimedean spiral scan with an outer regular hexagon step scan.The proposed composite scanning approach covers a wide range of the Field of Uncertainty(FOU)and reduces the required scans by actuator,which can ensure a high Acquisition Probability(AP)while reducing the Average Acquisition Time(AAT)for the inner scan.Specifically,we model and analyze the effect of satellite platform vibrations on the acquisition performance of our beaconless PAT scheme,and derive closed-form expressions for both AP and AAT by utilizing a 2-track model where the acquisition happens on two adjacent spiral scan tracks.By utilizing the theoretical derivations,we can achieve a minimum AAT under diverse APs by selecting appropriate values of overlapping region and scanning range.Simulation results validate that our optimized composite scanning approach for beaconless PAT scheme outperforms the existing schemes. 展开更多
关键词 Pointing acquisition and tracking Satellite constellations Optical communications Beaconless PAT scheme Composite scanning approach Satellite platform vibrations
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Diverse Models,United Goal:A Comprehensive Survey of Ensemble Learning
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作者 Ziwei Fan Zhiwen Yu +5 位作者 Kaixiang Yang Wuxing Chen Xiaoqing Liu Guojie Li Xianling Yang C.L.Philip Chen 《CAAI Transactions on Intelligence Technology》 2025年第4期959-982,共24页
Ensemble learning,a pivotal branch of machine learning,amalgamates multiple base models to enhance the overarching performance of predictive models,capitalising on the diversity and collective wisdom of the ensemble t... Ensemble learning,a pivotal branch of machine learning,amalgamates multiple base models to enhance the overarching performance of predictive models,capitalising on the diversity and collective wisdom of the ensemble to surpass individual models and mitigate overfitting.In this review,a four-layer research framework is established for the research of ensemble learning,which can offer a comprehensive and structured review of ensemble learning from bottom to top.Firstly,this survey commences by introducing fundamental ensemble learning techniques,including bagging,boosting,and stacking,while also exploring the ensemble's diversity.Then,deep ensemble learning and semi-supervised ensemble learning are studied in detail.Furthermore,the utilisation of ensemble learning techniques to navigate challenging datasets,such as imbalanced and highdimensional data,is discussed.The application of ensemble learning techniques across various research domains,including healthcare,transportation,finance,manufacturing,and the Internet,is also examined.The survey concludes by discussing challenges intrinsic to ensemble learning. 展开更多
关键词 BAGGING BOOSTING deep learning ensemble learning imbalanced data semi-supervised learning STACKING
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Robot Manipulation Based on Embodied Visual Perception:A Survey
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作者 Sicheng Wang Milutin N.Nikolić +3 位作者 Tin Lun Lam Qing Gao Runwei Ding Tianwei Zhang 《CAAI Transactions on Intelligence Technology》 2025年第4期945-958,共14页
Visual perception is critical in robotic operations,particularly in collaborative and autonomous robot systems.Through efficient visual systems,robots can acquire and process environmental information in real-time,rec... Visual perception is critical in robotic operations,particularly in collaborative and autonomous robot systems.Through efficient visual systems,robots can acquire and process environmental information in real-time,recognise objects,assess spatial relationships,and make adaptive decisions.This review aims to provide a comprehensive overview of the latest advancements in the field of vision as applied to robotic perception,focusing primarily on visual applications in the areas of object perception,self-perception,human-robot collaboration,and multi-robot collaboration.By summarising the current state of development and analysing the challenges and opportunities that remain in these areas,this paper offers a thorough examination of the integration of visual perception with operational robotics.It further inspires future research and drives the application and development of visual perception across various robotic domains,enabling operational robots to better adapt to complex environments and reliably accomplish tasks. 展开更多
关键词 3-D computer vision intelligent robots ROBOTICS
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High-speed video imaging via multiplexed temporal gradient snapshot
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作者 Yifei Zhang Xing Liu +6 位作者 Lishun Wang Ping Wang Ganzhangqin Yuan Mu Ku Chen Kui Jiang Xin Yuan Zihan Geng 《Advanced Photonics Nexus》 2025年第4期163-173,共11页
High-speed imaging is crucial for understanding the transient dynamics of the world,but conventional frame-by-frame video acquisition is limited by specialized hardware and substantial data storage requirements.We int... High-speed imaging is crucial for understanding the transient dynamics of the world,but conventional frame-by-frame video acquisition is limited by specialized hardware and substantial data storage requirements.We introduce“SpeedShot,”a computational imaging framework for efficient high-speed video imaging.SpeedShot features a low-speed dual-camera setup,which simultaneously captures two temporally coded snapshots.Cross-referencing these two snapshots extracts a multiplexed temporal gradient image,producing a compact and multiframe motion representation for video reconstruction.Recognizing the unique temporal-only modulation model,we propose an explicable motion-guided scale-recurrent transformer for video decoding.It exploits cross-scale error maps to bolster the cycle consistency between predicted and observed data.Evaluations on both simulated datasets and real imaging setups demonstrate SpeedShot’s effectiveness in video-rate up-conversion,with pronounced improvement over video frame interpolation and deblurring methods.The proposed framework is compatible with commercial low-speed cameras,offering a versatile low-bandwidth alternative for video-related applications,such as video surveillance and sports analysis. 展开更多
关键词 high-speed video compressive sensing coded exposure
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Age-Optimal Cached Distribution in the Satellite-Integrated Internet of Things via Cross-Slot Directed Graph
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作者 Hu Zhouyong Li Yue +1 位作者 Zhang Hanxu Yang Zhihua 《China Communications》 2025年第6期300-318,共19页
In the Satellite-integrated Internet of Things(S-IoT),data freshness in the time-sensitive scenarios could not be guaranteed over the timevarying topology with current distribution strategies aiming to reduce the tran... In the Satellite-integrated Internet of Things(S-IoT),data freshness in the time-sensitive scenarios could not be guaranteed over the timevarying topology with current distribution strategies aiming to reduce the transmission delay.To address this problem,in this paper,we propose an age-optimal caching distribution mechanism for the high-timeliness data collection in S-IoT by adopting a freshness metric,as called age of information(AoI)through the caching-based single-source multidestinations(SSMDs)transmission,namely Multi-AoI,with a well-designed cross-slot directed graph(CSG).With the proposed CSG,we make optimizations on the locations of cache nodes by solving a nonlinear integer programming problem on minimizing Multi-AoI.In particular,we put up forward three specific algorithms respectively for improving the Multi-AoI,i.e.,the minimum queuing delay algorithm(MQDA)based on node deviation from average level,the minimum propagation delay algorithm(MPDA)based on the node propagation delay reduction,and a delay balanced algorithm(DBA)based on node deviation from average level and propagation delay reduction.The simulation results show that the proposed mechanism can effectively improve the freshness of information compared with the random selection algorithm. 展开更多
关键词 age of information cached distribution satellite-integrated internet of things time-varying graph
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Chemical simulation teaching system based on virtual reality and gesture interaction 被引量:1
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作者 Dengzhen LU Hengyi LI +2 位作者 Boyu QIU Siyuan LIU Shuhan QI 《虚拟现实与智能硬件(中英文)》 EI 2024年第2期148-168,共21页
Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based ... Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based on virtual reality and gesture interaction.Methods The parameters of the models were obtained through actual investigation,whereby Blender and 3DS MAX were used to model and import these parameters into a physics engine.By establishing an interface for the physics engine,gesture interaction hardware,and virtual reality(VR)helmet,a highly realistic chemical experiment environment was created.Using code script logic,particle systems,as well as other systems,chemical phenomena were simulated.Furthermore,we created an online teaching platform using streaming media and databases to address the problems of distance teaching.Results The proposed system was evaluated against two mainstream products in the market.In the experiments,the proposed system outperformed the other products in terms of fidelity and practicality.Conclusions The proposed system which offers realistic simulations and practicability,can help improve the high school chemistry experimental education. 展开更多
关键词 Chemical experiment simulation Gesture interaction Virtual reality Model establishment Process control Streaming media DATABASE
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Layered Coded Cache Placement and Cooperative Delivery with Sharing Links in Satellite-Terrestrial Integrated Networks 被引量:1
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作者 Gu Shushi Chen Zihan +2 位作者 Wu Yaonan Zhang Qinyu Wang Ye 《China Communications》 SCIE CSCD 2024年第3期217-229,共13页
Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content deliver... Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content delivery over the seamless global coverage area. However, the on-board supportable resources of a single satellite are extremely limited and lack of interaction with others. In this paper, we design a network model with two-layered cache deployment, i.e., satellite layer and ground base station layer, and two types of sharing links, i.e., terrestrial-satellite sharing(TSS) links and inter-satellite sharing(ISS) links, to enhance the capability of cooperative delivery over STINs. Thus, we use rateless codes for the content divided-packet transmission, and derive the total energy efficiency(EE) in the whole transmission procedure, which is defined as the ratio of traffic offloading and energy consumption. We formulate two optimization problems about maximizing EE in different sharing scenarios(only TSS and TSS-ISS),and propose two optimized algorithms to obtain the optimal content placement matrixes, respectively.Simulation results demonstrate that, enabling sharing links with optimized cache placement have more than 2 times improvement of EE performance than other traditional placement schemes. Particularly, TSS-ISS schemes have the higher EE performance than only TSS schemes under the conditions of enough number of satellites and smaller inter-satellite distances. 展开更多
关键词 coded content placement cooperative delivery energy efficiency sharing links STINs
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Effects of virtual agents on interaction efficiency and environmental immersion in MR environments 被引量:1
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作者 Yihua BAO Jie GUO +2 位作者 Dongdong WENG Yue LIU Zeyu TIAN 《虚拟现实与智能硬件(中英文)》 EI 2024年第2期169-179,共11页
Background Physical entity interactions in mixed reality(MR)environments aim to harness human capabilities in manipulating physical objects,thereby enhancing virtual environment(VEs)functionality.In MR,a common strate... Background Physical entity interactions in mixed reality(MR)environments aim to harness human capabilities in manipulating physical objects,thereby enhancing virtual environment(VEs)functionality.In MR,a common strategy is to use virtual agents as substitutes for physical entities,balancing interaction efficiency with environmental immersion.However,the impact of virtual agent size and form on interaction performance remains unclear.Methods Two experiments were conducted to explore how virtual agent size and form affect interaction performance,immersion,and preference in MR environments.The first experiment assessed five virtual agent sizes(25%,50%,75%,100%,and 125%of physical size).The second experiment tested four types of frames(no frame,consistent frame,half frame,and surrounding frame)across all agent sizes.Participants,utilizing a head mounted display,performed tasks involving moving cups,typing words,and using a mouse.They completed questionnaires assessing aspects such as the virtual environment effects,interaction effects,collision concerns,and preferences.Results Results from the first experiment revealed that agents matching physical object size produced the best overall performance.The second experiment demonstrated that consistent framing notably enhances interaction accuracy and speed but reduces immersion.To balance efficiency and immersion,frameless agents matching physical object sizes were deemed optimal.Conclusions Virtual agents matching physical entity sizes enhance user experience and interaction performance.Conversely,familiar frames from 2D interfaces detrimentally affect interaction and immersion in virtual spaces.This study provides valuable insights for the future development of MR systems. 展开更多
关键词 Mixed reality Virtual agents Interaction performance Environmental immersion Virtual environments
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Boosting Adaptive Weighted Broad Learning System for Multi-Label Learning
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作者 Yuanxin Lin Zhiwen Yu +2 位作者 Kaixiang Yang Ziwei Fan C.L.Philip Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第11期2204-2219,共16页
Multi-label classification is a challenging problem that has attracted significant attention from researchers, particularly in the domain of image and text attribute annotation. However, multi-label datasets are prone... Multi-label classification is a challenging problem that has attracted significant attention from researchers, particularly in the domain of image and text attribute annotation. However, multi-label datasets are prone to serious intra-class and inter-class imbalance problems, which can significantly degrade the classification performance. To address the above issues, we propose the multi-label weighted broad learning system(MLW-BLS) from the perspective of label imbalance weighting and label correlation mining. Further, we propose the multi-label adaptive weighted broad learning system(MLAW-BLS) to adaptively adjust the specific weights and values of labels of MLW-BLS and construct an efficient imbalanced classifier set. Extensive experiments are conducted on various datasets to evaluate the effectiveness of the proposed model, and the results demonstrate its superiority over other advanced approaches. 展开更多
关键词 Broad learning system label correlation mining label imbalance weighting multi-label imbalance
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An mmWave Dual-Band Integrated Substrate Gap Waveguide Single Cavity Filter with Frequency Selectivity
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作者 Qiuhua Lin Dongya Shen +1 位作者 Lihui Wang Zhiyong Luo 《China Communications》 SCIE CSCD 2024年第1期188-199,共12页
A novel dual-band ISGW cavity filter with enhanced frequency selectivity is proposed in this paper by utilizing a multi-mode coupling topology.Its cavity is designed to control the number of modes,and then the ports a... A novel dual-band ISGW cavity filter with enhanced frequency selectivity is proposed in this paper by utilizing a multi-mode coupling topology.Its cavity is designed to control the number of modes,and then the ports are determined by analyzing the coupling relationship between these selected modes.By synthesizing the coupling matrix of the filter,a nonresonating node(NRN)structure is introduced to flexibly tune the frequency of modes,which gets a dualband and quad-band filtering response from a tri-band filter no the NRN.Furthermore,a frequency selective surface(FSS)has been newly designed as the upper surface of the cavity,which significantly improves the bad out-of-band suppression and frequency selectivity that often exists in most traditional cavity filter designs and measurements.The results show that its two center frequencies are f01=27.50 GHz and f02=32.92GHz,respectively.Compared with the dual-band filter that there is no the FSS metasurface,the out-of-band suppression level is improved from measured 5 dB to18 dB,and its finite transmission zero(FTZ)numbers is increased from measured 1 to 4 between the two designed bands.Compared with the tri-band and quadband filter,its passband bandwidth is expanded from measured 1.17%,1.14%,and 1.13% or 1.31%,1.50%,0.56%,and 0.57% to 1.71% and 1.87%.In addition,the filter has compact,small,and lightweight characteristics. 展开更多
关键词 coupling topology frequency selectivity non-resonating node(NRN) out-of-band suppression single ISGW cavity filter
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Dual-channel quantum meta-hologram for display 被引量:1
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作者 Yubin Fan Hong Liang +6 位作者 Yuhan Wang Shufan Chen Fangxing Lai Mu Ku Chen Shumin Xiao Jensen Li Din Ping Tsai 《Advanced Photonics Nexus》 2024年第1期86-92,共7页
Quantum technologies rely on creating and manipulating entangled sources,which are essential for quantum information,communication,and imaging.By integrating quantum technologies and all-dielectric metasurfaces,the pe... Quantum technologies rely on creating and manipulating entangled sources,which are essential for quantum information,communication,and imaging.By integrating quantum technologies and all-dielectric metasurfaces,the performance of miniature display devices can be enhanced to a higher level.Miniature display technology,such as virtual reality display,has achieved original commercial success,and was initially applied to immersive games and interactive scenes.While the consumer market has quickly adopted this technology,several areas remain for improvement,including concerns around bulkiness,dual-channel display,and noise reduction.Here,we experimentally realize a quantum meta-hologram concept demonstration of a miniature display.We fabricate an ultracompact meta-hologram based on 1μm thick titanium dioxide(TiO_(2)).The meta-hologram can be remotely switched with heralding technique and is robust against noise with the quantum entangled source.The platform can alter the miniature display channel by manipulating heralding photons’polarization,removing speckles and multiple reflective light noise,improving imaging contrast,and potentially decreasing device weight.Imaging contrast increases from 0.36 dB under speckle noise influences to 6.8 dB in quantum correlation imaging.This approach has the potential to miniaturize quantum displays and quantum communication devices. 展开更多
关键词 QUANTUM meta-hologram DISPLAY metasurface dual channel
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Adaptive Resources Allocation Algorithm Based on Modified PSO for Cognitive Radio System 被引量:9
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作者 Yi Yang Qinyu Zhang +3 位作者 Ye Wang Takahiro Emoto Masatake Akutagawa Shinsuke Konaka 《China Communications》 SCIE CSCD 2019年第5期83-92,共10页
Radio spectrum has become a rare resource due to the rapid development of wireless communication technique. Cognitive radio is one of important techniques to deal with this radio spectrum problem. But the resource all... Radio spectrum has become a rare resource due to the rapid development of wireless communication technique. Cognitive radio is one of important techniques to deal with this radio spectrum problem. But the resource allocation in cognitive radio also has its own issues, such as the flexibility of the allocation algorithm, the performance of resource allocation, and so on. In order to increase the flexibility of the allocation algorithm for cognitive radio, more and more researches are focusing on the evolutionary algorithms, such as genetic algorithm(GA), particle swarm optimization(PSO). Evolutionary algorithm can greatly improve the flexibility of the allocation algorithm for cognitive radio system in different communication scenarios, but the performances are relatively lower than the original mathematical methods. So in this paper, we proposed an adaptive resource allocation algorithm based on modified PSO for cognitive radio system to solve these problems. Modified particle swarm optimization(Modified PSO) has both genetic algorithm(GA) and particle swarm optimization(PSO)’s updating processes which makes this modified PSO overcame PSO’s own disadvantages and keep advantages. Simulation results showed our proposed algorithm has enough flexibility to meet cognitive radio systems’ requirements, and also has a better performance than original PSO. 展开更多
关键词 COGNITIVE RADIO particle SWARM optimization GENETIC ALGORITHM performance analysis FLEXIBILITY
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Prediction Model of Refined Gasoline Blending Formula Based on PSO-DBN 被引量:3
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作者 Wang Xiaoming Li Wei +2 位作者 Li Yajie Jiang Dongnian Liang Chenglong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2022年第3期128-138,共11页
To address the problem of the low accuracy of refined gasoline blending formula in the petrochemical industry,the advantages of deep belief networks(DBNs)in feature extraction and nonlinear processing are considered,a... To address the problem of the low accuracy of refined gasoline blending formula in the petrochemical industry,the advantages of deep belief networks(DBNs)in feature extraction and nonlinear processing are considered,and they are applied to the prediction modeling of refined gasoline blending conservative formula.Firstly,based on historical measured data of refined gasoline blending and according to the characteristics of the data set,we use bootstrapping to divide the training data set and the test data set.Secondly,considering that parameter selection for the network is difficult,particle swarm optimization is adopted to improve the related optimal parameters and replace the tedious process of manually selecting parameters,greatly improving optimization efficiency.In addition,the contrastive divergence algorithm is used for unsupervised forward feature learning and supervised reverse fine-tuning of the network,so as to construct a more accurate prediction model for conservative formula.Finally,in order to evaluate the effectiveness of this method,the simulation results are compared with those of traditional modeling methods,which show that the DBNs has better prediction performance than error back propagation and support vector machines,and can provide production guidance for refined gasoline blending formula. 展开更多
关键词 formulation PREDICTION deep belief network contrastive divergence particle swarm optimization
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Multi-Scenario Millimeter Wave Wireless Channel Measurements and Sparsity Analysis 被引量:4
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作者 Hang Mi Bo Ai +5 位作者 Ruisi He Xin Zhou Zhangfeng Ma Mi Yang Zhangdui Zhong Ning Wang 《China Communications》 SCIE CSCD 2022年第11期16-31,共16页
Wireless channel characteristics have significant impacts on channel modeling,estimation,and communication performance.While the channel sparsity is an important characteristic of wireless channels.Utilizing the spars... Wireless channel characteristics have significant impacts on channel modeling,estimation,and communication performance.While the channel sparsity is an important characteristic of wireless channels.Utilizing the sparse nature of wireless channels can reduce the complexity of channel modeling and estimation,and improve system design and performance analysis.Compared with the traditional sub6 GHz channel,millimeter wave(mmWave)channel has been considered to be more sparse in existing researches.However,most research only assume that the mmWave channel is sparse,without providing quantitative analysis and evaluation.Therefore,this paper evaluates the sparsity of mmWave channels based on mmWave channel measurements.A vector network analyzer(VNA)-based mmWave channel sounder is developed to measure the channel at 28 GHz,and multi-scenario channel measurements are conducted.The Gini index,Rician𝐾factor and rootmean-square(RMS)delay spread are used to measure channel sparsity.Then,the key factors affecting mmWave channel sparsity are explored.It is found that antenna steering direction and scattering environment will affect the sparsity of mmWave channel.In addition,the impact of channel sparsity on channel eigenvalue and capacity is evaluated and analyzed. 展开更多
关键词 channel sparsity channel measurement mmWave channel measures of sparsity
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Extrapolation over temporal knowledge graph via hyperbolic embedding 被引量:3
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作者 Yan Jia Mengqi Lin +5 位作者 Ye Wang Jianming Li Kai Chen Joanna Siebert Geordie Z.Zhang Qing Liao 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第2期418-429,共12页
Predicting potential facts in the future,Temporal Knowledge Graph(TKG)extrapolation remains challenging because of the deep dependence between the temporal association and semantic patterns of facts.Intuitively,facts(... Predicting potential facts in the future,Temporal Knowledge Graph(TKG)extrapolation remains challenging because of the deep dependence between the temporal association and semantic patterns of facts.Intuitively,facts(events)that happened at different timestamps have different influences on future events,which can be attributed to a hierarchy among not only facts but also relevant entities.Therefore,it is crucial to pay more attention to important entities and events when forecasting the future.However,most existing methods focus on reasoning over temporally evolving facts or mining evolutional patterns from known facts,which may be affected by the diversity and variability of the evolution,and they might fail to attach importance to facts that matter.Hyperbolic geometry was proved to be effective in capturing hierarchical patterns among data,which is considered to be a solution for modelling hierarchical relations among facts.To this end,we propose ReTIN,a novel model integrating real-time influence of historical facts for TKG reasoning based on hyperbolic geometry,which provides low-dimensional embeddings to capture latent hierarchical structures and other rich semantic patterns of the existing TKG.Considering both real-time and global features of TKG boosts the adaptation of ReTIN to the ever-changing dynamics and inherent constraints.Extensive experiments on benchmarks demonstrate the superiority of ReTIN over various baselines.The ablation study further supports the value of exploiting temporal information. 展开更多
关键词 EXTRAPOLATION hyperbolic embedding temporal knowledge graph
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Blockchain-Based Data Acquisition with Privacy Protection in UAV Cluster Network 被引量:1
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作者 Lemei Da Hai Liang +3 位作者 Yong Ding Yujue Wang Changsong Yang Huiyong Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期879-902,共24页
The unmanned aerial vehicle(UAV)self-organizing network is composed of multiple UAVs with autonomous capabilities according to a certain structure and scale,which can quickly and accurately complete complex tasks such... The unmanned aerial vehicle(UAV)self-organizing network is composed of multiple UAVs with autonomous capabilities according to a certain structure and scale,which can quickly and accurately complete complex tasks such as path planning,situational awareness,and information transmission.Due to the openness of the network,the UAV cluster is more vulnerable to passive eavesdropping,active interference,and other attacks,which makes the system face serious security threats.This paper proposes a Blockchain-Based Data Acquisition(BDA)scheme with privacy protection to address the data privacy and identity authentication problems in the UAV-assisted data acquisition scenario.Each UAV cluster has an aggregate unmanned aerial vehicle(AGV)that can batch-verify the acquisition reports within its administrative domain.After successful verification,AGV adds its signcrypted ciphertext to the aggregation and uploads it to the blockchain for storage.There are two chains in the blockchain that store the public key information of registered entities and the aggregated reports,respectively.The security analysis shows that theBDAconstruction can protect the privacy and authenticity of acquisition data,and effectively resist a malicious key generation center and the public-key substitution attack.It also provides unforgeability to acquisition reports under the Elliptic Curve Discrete Logarithm Problem(ECDLP)assumption.The performance analysis demonstrates that compared with other schemes,the proposed BDA construction has lower computational complexity and is more suitable for the UAV cluster network with limited computing power and storage capacity. 展开更多
关键词 Unmanned aerial vehicle cluster network certificateless signcryption certificateless signature batch verification source authentication data privacy blockchain
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Identifier Management of Industrial Internet Based on Multi-Identifier Network Architecture 被引量:1
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作者 WANG Yunmin LI Hui +4 位作者 XING Kaixuan HOU Hanxu Yunghsiang SHAN LIU Ji SUN Tao 《ZTE Communications》 2020年第1期36-43,共8页
The industrial Internet realizes intelligent control and optimized operation of the industrial system through network interconnection.The industrial Internet identifier is the core element to accomplish this task.The ... The industrial Internet realizes intelligent control and optimized operation of the industrial system through network interconnection.The industrial Internet identifier is the core element to accomplish this task.The traditional industrial Internet identifier resolution technologies depend excessively on IP networks,and cannot meet the requirements of ubiquitous resource-restraint Internet of Things(IoT)devices.An industrial Internet identifier resolution management strategy based on multi-identifier network architecture is proposed in this paper,which supports content names,identities,locations,apart from the traditional IP address.The application of multiple types of identifiers not only solves the problem of IP addresses exhaustion,but also enhances the security,credibility,and availability of the industrial Internet identification resolution system.An inter-translation scheme between multiple identifiers is designed to support multiple identifiers and the standard ones.We present an addressing and routing algorithm for identifier resolution to make it convenient to put our strategy into practice. 展开更多
关键词 identifier resolution industrial Internet inter-translation multiple identifier routing and addressing
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Specialty optical fibers for advanced sensing applications 被引量:3
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作者 Huanhuan Liu Dora Juan Juan Hu +10 位作者 Qizhen Sun Lei Wei Kaiwei Li Changrui Liao Bozhe Li Cong Zhao Xinyong Dong Yuhan Tang Yihong Xiao Gerd Keiser Perry Ping Shum 《Opto-Electronic Science》 2023年第2期1-26,共26页
Optical fiber technology has changed the world by enabling extraordinary growth in world-wide communications and sensing.The rapid development and wide deployment of optical fiber sensors are driven by their excellent... Optical fiber technology has changed the world by enabling extraordinary growth in world-wide communications and sensing.The rapid development and wide deployment of optical fiber sensors are driven by their excellent sensing performance with outstanding flexibility,functionality,and versatility.Notably,the research on specialty optical fibers is playing a critical role in enabling and proliferating the optical fiber sensing applications.This paper overviews recent developments in specialty optical fibers and their sensing applications.The specialty optical fibers are reviewed based on their innovations in special structures,special materials,and technologies to realize lab in/on a fiber.An overview of sensing applications in various fields is presented.The prospects and emerging research areas of specialty optical fibers are also discussed. 展开更多
关键词 specialty optical fibers photonic crystal fiber MULTIFUNCTIONAL multi-material fibers lab in/on fiber
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An achromatic metasurface waveguide for augmented reality displays 被引量:2
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作者 Zhongtao Tian Xiuling Zhu +2 位作者 Philip A.Surman Zhidong Chen Xiao Wei Sun 《Light(Science & Applications)》 2025年第4期984-991,共8页
Augmented reality(AR)displays are emerging as the next generation of interactive platform,providing deeper humandigital interactions and immersive experiences beyond traditional flat-panel displays.Diffractive wavegui... Augmented reality(AR)displays are emerging as the next generation of interactive platform,providing deeper humandigital interactions and immersive experiences beyond traditional flat-panel displays.Diffractive waveguide is a promising optical combiner technology for AR owing to its potential for the slimmest geometry and lightest weight.However,severe chromatic aberration of diffractive coupler has constrained widespread adoption of diffractive waveguide.Wavelength-dependent light deflection,caused by dispersion in both in-coupling and out-coupling processes,results in limited full-color field of view(FOV)and nonuniform optical responses in color and angular domains.Here we introduce an innovative full-color AR system that overcomes this long-standing challenge of chromatic aberration using a combination of inverse-designed metasurface couplers and a high refractive index waveguide.The optimized metasurface couplers demonstrate true achromatic behavior across the maximum FOV supported by the waveguide(exceeding 45°).Our AR prototype based on the designed metasurface waveguide,exhibits superior color accuracy and uniformity.This unique achromatic metasurface waveguide technology is expected to advance the development of visually compelling experience in compact AR display systems. 展开更多
关键词 chromatic aberration diffractive waveguidewavelength dependent optical combiner technology deeper humandigital interactions ACHROMATIC metasurface augmented reality waveguide
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