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An Efficient Radar Detection Method of Maneuvering Small Targets

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Journal of Beijing Institute of Technology 2024年第1期33卷 1-8页

作者： Hongchi Zhang Yuan Feng Shengheng Liu School of information and Electronics Beijing Institute of Technology and Beijing Key Laboratory of Fractional Signals and SystemsBeijing 100081China School of information Science and Engineering Southeast UniversityNanjing 210096China

Detection of maneuvering small targets has always been an important yet challenging task for radar signal *** primary reason is that target variable motions within coherent processing interval generate energy migrations across multiple resolution bins,which severely deteriorate the parameter estimation performance.A coarse-to-fine strategy for the detection of maneuvering small targets is *** of small points segmented coherently is performed first,and then an optimal inter-segment integration is utilized to derive the coarse estimation of the chirp *** fractional Fourier transform(FrFT)is then employed to refine the coarse estimation at a significantly reduced computational *** results verify the proposed scheme that achieves an efficient and reliable maneuvering target detection with-16dB input signal-to-noise ratio(SNR),while requires no exact a priori knowledge on the motion parameters.

关键词： small target chirp sparse fractional Fourier transform(FrFT)

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Broadband high-efficiency dielectric metalenses based on quasi-continuous nanostrips

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Opto-Electronic Advances 2024年第5期7卷 43-51页

作者： Xiaohu Zhang Qinmiao Chen Dongliang Tang Kaifeng Liu Haimo Zhang Lintong Shi Mengyao He Yongcai Guo Shumin Xiao Key laboratory of optoelectronic Technology and systems of the Education Ministry of China Chongqing UniversityChongqing 400044China Ministry of Industry and information Technology Key Lab of Micro-Nano Optoelectronic information System Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic SystemsHarbin Institute of TechnologyShenzhen 518055China Key laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education&Hunan Provincial Key laboratory of Low-Dimensional Structural Physics and Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China

Benefiting from the abrupt phase changes within subwavelength thicknesses,metasurfaces have been widely applied for lightweight and compact optical *** broadband and high-efficiency characteristics are highly attractive for the practical implementation of ***,current metasurface devices mostly adopt discrete micro/nano structures,which rarely realize both merits *** this paper,dielectric metasurfaces composed of quasi-continuous nanostrips are proposed to overcome this *** quasi-continuous nanostrips metasurface,a normal focusing metalens and a superoscillatory lens overcoming the diffraction limit are designed and experimentally *** quasi-continuous metadevices can operate in a broadband wavelength ranging from 450 nm to 1000nm and keep a high power *** average efficiency of the fabricated metalens reaches 54.24%,showing a significant improvement compared to the previously reported metalenses with the same *** proposed methodology can be easily extended to design other metadevices with the advantages of broadband and high-efficiency in practical optical systems.

关键词： broadband high-efficiency metalens sub-diffraction quasi-continuous

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Experimental demonstration of a quantum downstream access network in continuous variable quantum key distribution with a local local oscillator

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Photonics Research 2024年第6期12卷 1262-1273页

作者： DENGKE QI XIANGYU WANG ZHENGHUA LI JIAYU MA ZIYANG CHEN YUEMING LU SONG YU State Key laboratory of information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China Key laboratory of Trustworthy Distributed Computing and Service(MoE) Beijing University of Posts and TelecommunicationsBeijing 100876China State Key laboratory of Advanced Optical Communication systems and Networks School of Electronicsand Center for Quantum Information TechnologyPeking UniversityBeijing 100871China

Quantum networks provide opportunities and challenges across a range of intellectual and technical frontiers,including quantum computation,communication,and *** traditional communication networks,quantum networks utilize quantum bits rather than classical bits to store and transmit *** key distribution(QKD)relying on the principles of quantum mechanics is a key component in quantum networks and enables two parties to produce a shared random secret key,thereby ensuring the security of data *** this work,we propose a cost-effective quantum downstream access network structure in which each user can get their corresponding key information through terminal *** on this structure,we demonstrate the first four-end-users quantum downstream access network in continuous variable QKD with a local local *** contrast to point-to-point continuous variable QKD,the network architecture reevaluates the security of each user and accounts for it accordingly,and each user has a lower tolerance for excess noise as the overall network expands with more ***,the feasibility of the experiment is based on the analysis of the theoretical model,noise analysis,and multiple techniques such as the particle filter and adaptive equalization algorithm used to suppress excess *** results show that each user can get a low level of excess noise and can achieve secret key rates of 546 kbps,535 kbps,522.5 kbps,and 512.5 kbps under a transmission distance of 10 km,respectively,with the finite-size block of 1×10^(8).This not only verifies the good performance but also provides the foundation for the future multi-user quantum downstream access networks.

关键词： quantum oscillator local

Flexible incidence angle scanning surface plasmon resonance microscopy for morphology detection with enhanced contrast

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Photonics Research 2024年第6期12卷 1213-1221页

作者： LINGKE WANG JINGYU MI SHUQI WANG WENRUI LI JU TANG JIAWEI ZHANG JIWEI ZHANG JIANLIN ZHAO Key laboratory of Light Field Manipulation and information Acquisition Ministry of Industry and Information Technologyand Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710129China

Surface plasmon resonance microscopy(SPRM)has been massively applied for near-field optical measurement,sensing,and imaging because of its high detection sensitivity,nondestructive,noninvasive,wide-field,and label-free imaging ***,the transverse propagation characteristic of the surface plasmon wave generated during surface plasmon resonance(SPR)leads to notable“tail”patterns in the SPR image,which severely deteriorates the image ***,we propose an incidence angle scanning method in SPRM to obtain a resonance angle image with exceptional contrast that significantly mitigates the adverse effects of“tail”*** resonance angle image provides the complete morphology of the analyzed samples and enables two-dimensional quantification,which is incapable in conventional *** effectiveness of the method was experimentally verified using photoresist square samples with different sizes and two-dimensional materials with various geometric *** edges of samples were fully reconstructed and a maximum fivefold increase in the image contrast has been *** method offers a convenient way to enhance the SPRM imaging capabilities with low cost and stable performance,which greatly expands the applications of SPRM in label-free detection,imaging,and quantification.

关键词： angle resonance surface

Enhancing Ulcerative Colitis Diagnosis:A Multi-Level Classification Approach with Deep Learning

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 1129-1142页

作者： Hasan J.Alyamani Department of information systems Faculty of Computing and Information Technology in RabighKing Abdulaziz UniversityJeddah21589Saudi Arabia

The evaluation of disease severity through endoscopy is pivotal in managing patients with ulcerative colitis,a condition with significant clinical ***,endoscopic assessment is susceptible to inherent variations,both within and between observers,compromising the reliability of individual *** study addresses this challenge by harnessing deep learning to develop a robust model capable of discerning discrete levels of endoscopic disease *** initiate this endeavor,a multi-faceted approach is embarked *** dataset is meticulously preprocessed,enhancing the quality and discriminative features of the images through contrast limited adaptive histogram equalization(CLAHE).A diverse array of data augmentation techniques,encompassing various geometric transformations,is leveraged to fortify the dataset’s diversity and facilitate effective feature extraction.A fundamental aspect of the approach involves the strategic incorporation of transfer learning principles,harnessing a modified ResNet-50 *** augmentation,informed by domain expertise,contributed significantly to enhancing the model’s classification *** outcome of this research endeavor yielded a highly promising model,demonstrating an accuracy rate of 86.85%,coupled with a recall rate of 82.11%and a precision rate of 89.23%.

关键词： Ulcerative colitis deep learning CLAHE transfer learning geometric transformations

Finite-time tracking control of heterogeneous multi-AUV systems with partial measurements and intermittent communication

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Science China(information Sciences) 2024年第5期67卷 165-182页

作者： Bo CHEN Jiangping HU Bijoy Kumar GHOSH School of Automation Engineering University of Electronic Science and Technology of China Key laboratory of Intelligent Analysis and decision on Complex systems Chongqing University of Posts and Telecommunications Yangtze Delta Region Institute (Huzhou) University of Electronic Science and Technology of China Department of Mathematics and Statistics Texas Tech University

The development of a distributed trajectory-tracking control strategy that is independent of velocity measurements is critical to achieving finite-time tracking control of autonomous underwater vehicle(AUV) systems. In this study, a group of heterogeneous AUV systems with intermittent communication links is considered and a finite-time trajectory-tracking control strategy is developed. The strategy includes two observers and one controller proposed for each follower-AUV. The first observer, a hybrid finite-time observer,estimates the state of the leader, whereas the second observer, which relies only on the position measurement,is proposed to estimate the states of the follower-AUV itself. In addition, a distributed trajectory-tracking controller is designed using the states estimated by the intermittent communication network even without velocity measurements. A homogeneous technique is utilized to prove that all followers can track the leader in a finite time. Finally, the effectiveness of the developed finite-time tracking control strategy is illustrated by numerical simulations.

关键词： distributed observer finite-time tracking homogeneous technique intermittent communication multiple heterogeneous AUVs

Lead-free perovskites-based photonic synaptic devices with zero electric energy consumption

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Science China(information Sciences) 2024年第6期67卷 433-441页

作者： Dandan HAO Di YANG Haixia LIANG Jia HUANG Fukai SHAN College of Electronics and information Qingdao University Key laboratory of Biofuels Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences School of Materials Science and Engineering Tongji University National Key laboratory of Autonomous Intelligent Unmanned systems Tongji University

The von Neumann bottleneck is a critical limitation in synaptic devices. Therefore, artificial synaptic devices resembling biological neuromorphic synapses have been developed to overcome the von Neumann bottleneck. However, synaptic devices require voltages, which results in considerable energy consumption. Here, photonic synaptic devices with the vertical structure of indium tin oxide（ITO）/SnO2/Al2O3/CsBi3I10/Au are fabricated, which can work in the self-powered mode owing to the photovoltaic effect endowed by a vertical multilayer structure. Several fundamental synaptic functions, such as excitatory postsynaptic current, paired-pulse facilitation, short-term plasticity（STP）, long-term plasticity（LTP）, pulse-frequency-dependent plasticity, transition of STP to LTP, and the learning experience are emulated. Moreover, Morse-coded external light information is decoded by self-powered photonic synaptic devices. The results indicate that self-powered photonic synaptic devices based on lead-free perovskites exhibit great potential for efficient neuromorphic computing and optical wireless communication.

关键词： photonic synaptic devices lead-free perovskites zero energy consumption synaptic plasticity Morse code

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DCFNet:Discriminant Correlation Filters Network for Visual Tracking

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Journal of Computer Science & Technology 2024年第3期39卷 691-714页

作者：胡卫明王强高晋李兵 Stephen Maybank State Key laboratory of Multimodal Artificial Intelligence systems Institute of AutomationChinese Academy of Sciences Beijing 100190China Department of Computer Science and information systems Birkbeck CollegeLondon WC1E 7HXU.K.

CNN(convolutional neural network)based real time trackers usually do not carry out online network update in order to maintain rapid tracking *** inevitably influences the adaptability to changes in object *** filter based trackers can update the model parameters online in real *** this paper,we present an end-to-end lightweight network architecture,namely Discriminant Correlation Filter Network(DCFNet).A differentiable DCF(discriminant correlation filter)layer is incorporated into a Siamese network architecture in order to learn the convolutional features and the correlation filter *** correlation filter can be efficiently updated *** previous work,we introduced a joint scale-position space to the DCFNet,forming a scale DCFNet which carries out the predictions of object scale and position *** combine the scale DCFNet with the convolutional-deconvolutional network,learning both the high-level embedding space representations and the low-level fine-grained representations for *** adaptability of the fine-grained correlation analysis and the generalization capability of the semantic embedding are complementary for visual *** back-propagation is derived in the Fourier frequency domain throughout the entire work,preserving the efficiency of the *** evaluations on the OTB(Object Tracking Benchmark)and VOT(Visual Object Tracking Challenge)datasets demonstrate that the proposed trackers have fast speeds,while maintaining tracking accuracy.

关键词： correlation filter convolutional neural network(CNN) visual tracking

A survey of decision making in adversarial games

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Science China(information Sciences) 2024年第4期67卷 85-112页

作者： Xiuxian LI Min MENG Yiguang HONG Jie CHEN College of Electronics and information Engineering Tongji University Shanghai Research Institute for Intelligent Autonomous systems

In many practical applications, such as poker, chess, drug interdiction, cybersecurity, and national defense, players often have adversarial stances, i.e., the selfish actions of each player inevitably or intentionally inflict loss or wreak havoc on other players. Therefore, adversarial games are important in realworld applications. However, only special adversarial games, such as Bayesian games, are reviewed in the literature. In this respect, this study aims to provide a systematic survey of three main game models widely employed in adversarial games, i.e., zero-sum normal-form and extensive-form games, Stackelberg(security) games, and zero-sum differential games, from an array of perspectives, including basic knowledge of game models,(approximate) equilibrium concepts, problem classifications, research frontiers,(approximate) optimal strategy-seeking techniques, prevailing algorithms, and practical applications. Finally, promising future research directions are also discussed for relevant adversarial games.

关键词： adversarial games zero-sum games Stackelberg games differential games Nash equilibrium correlated equilibrium regret

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