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Dual-Mode Resonant Sectorial Monopole Antenna with Stable Backfire Gain

Chinese Journal of Electronics 2024年第6期33卷 1478-1486页

作者： Feiyan JI Heng ZHANG Xiuqiong XING Wenjun LU Lei ZHU Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Department of Electrical and Computer Engineering Faculty of Science and Technology University of Macau

A novel design approach to wideband, dual-mode resonant monopole antenna with stable, enhanced backfire gain is advanced. The sectorial monopole evolves from a linear, 0.75-wavelength electric prototype monopole under wideband dual-mode resonant operation. As theoretically predicted by the two resonant modes TE3/5,1and TE9/5,1within a 150° radiator, the operation principle is revealed at first. As have been numerically demonstrated and experimentally validated at 2.4-GHz band, the designed antenna exhibits a wide impedance bandwidth over 90.1%（i.e., 2.06–5.44 GHz）, in which the stable gain bandwidth in the backfire,-x-direction（θ = 90°, φ = 180°） with peak value of 3.2 dBi and fluctuation less than 3 dB is up to 45.3%（i.e., 3.74–5.44 GHz）. It is concluded that the stable wideband backfire gain frequency response should be owing to the high-order resonant mode in the unique sectorial monopole antennas.

关键词： Fluctuations Azimuth Prototypes Metals Resonance Frequency measurement Broadband antennas Impedance Gain Wideband

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A Novel Sleep Modulation and Quality Classification Strategy Based EEG Signals and Multi-Scale Attention Deep Learning

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IEEE Internet of Things Journal 2025年第11期12卷 17377-17386页

作者： Lou, Yajun Zhou, Lu Song, Fanlei Xu, Fanyao Wang, Xuejing Li, Weitao Qian, Zhiyu Nanjing University of Aeronautics and Astronautics Key Laboratory of Multimodal Brain-Computer Precision Drive Ministry of Industry and Information Technology the Key Laboratory of Digital Medical Equipment and Technology of Jiangsu Province Department of Biomedical Engineering College of Automation Engineering Nanjing210016 China

Sleep disorders have become the second most prevalent mental health condition globally, posing a significant challenge to public health. Consequently, there is an imperative need for the development of effective, non-pharmacological interventions to enhance sleep quality. In this study, a novel sleep modulation technique utilizing transcutaneous electrical nerve stimulation (TENS) is introduced. A specialized stimulation mode is designed by integrating sine waves of varying frequencies, including spindle waveform components. Additionally, to facilitate an accurate evaluation of sleep quality and enable individualized interventions, a multi-scale attention-based deep learning model (MSA-Net) is proposed for sleep quality classification. It consists of a two-branch convolution block (TBC-block), an adaptive feature recalibration (AFR) module, three dense blocks, three attention transition blocks. By extracting the deep features of the electroencephalography (EEG) raw data, the sleep quality classification is realized. Experimental results indicate that the proposed stimulation effectively enhances and stabilizes slow-wave activity, significantly extending the duration of deep sleep and enhancing overall sleep stability. In addition, the MSA-Net demonstrates robust performance, achieving exceptional performance with an overall accuracy of 0.881, F1 score of 0.903, and Kappa score of 0.845, outperforming baseline models across all evaluation metrics. These results demonstrate the potential of combining TENS-based sleep modulation with deep learning techniques, offering an effective framework for enhancing sleep quality and advancing personalized sleep modulation strategies. © 2025 IEEE.

关键词： Sleep research

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A Low-Profile Tri-Port Multimode Metasurface-Based Antenna Using Characteristic Mode Analysis

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IEEE Antennas and Wireless Propagation Letters 2025年第5期24卷 1119-1123页

作者： Jiang, Zhaoneng Meng, Shuai Nie, Liying Qi, Jiquan Ji, Fangzheng Hefei University of Technology School of Computer Science and Information Hefei230009 China Southeast University National Mobile Commnications Research Laboratory Jiangsu210096 China Hefei University of Technology School of Computer Science Hefei China Huzhou Key Laboratory of Information-Energy Convergence and Interconnection Huzhou313001 China Hefei University of Technology School of Microelectronics Hefei China

In this letter, a metasurface (MTS)-based antenna is proposed for low-profile and multimode operation. An Omnidirectional radiation pattern is excited through a central coaxial cable. A pair of e-TM20 modes with broadside radiation patterns are excited via slot coupling. The size and shape of the peripheral patches of the MTS were adjusted by using characteristic mode analysis (CMA) to increase the bandwidth of the omnidirectional mode and decrease the resonant frequency of the e-TM20 mode. Three modes can operate independently without interfering due to the properly designed feeding networks for each mode. The isolation between ports is greater than 25 dB. The optimized size of the antenna is 0.96 λmin × 0.96 λmin × 0.07 λmin. By enabling multiple modes to operate in different frequency bands on a single MTS, antenna cost, and occupied space can be significantly reduced. © 2002-2011 IEEE.

关键词： Antennas Antenna radiation patterns Bandwidth Scattering parameters Broadband antennas Gain Current distribution Resonant frequency Impedance matching Impedance

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Experimental deformation of shales at elevated temperature and pressure:Pore-crack system evolution and its effects on shale gas reservoirs

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Petroleum Science 2024年第6期21卷 3754-3773页

作者： Yi-Wen Ju Xin-Gao Hou Kui Han Yu Song Lei Xiao Cheng Huang Hong-Jian Zhu Li-Ru Tao Key Laboratory of Earth System Numerical Modeling and Application College of Earth and Planetary SciencesUniversity of Chinese Academy of SciencesChinese Academy of SciencesBeijing100049China Key Laboratory of Earth Exploration and Information Technique Ministry of EducationCollege of GeophysicsChengdu University of TechnologyChengdu610059SichuanChina Key Laboratory of Coalbed Methane Resource&Reservoir Formation Process Ministry of EducationSchool of Resources&Earth ScienceChina University of Mining and TechnologyXuzhou221116JiangsuChina

Although many studies based on naturally deformed samples have been carried out to investigate the pore-crack characteristics of shales,studies based on high temperature(T)and high pressure(P)deformation experiments,which can exclude sample heterogeneity factors,simulate deep T-P conditions,and generate a continuous deformation sequence,are still *** this study,shales with different deformation levels are generated by triaxial compression experiments,and methods including scanning electron microscopy,mercury injection,and gas sorption are utilized to characterize their influence factors and pore-crack *** indicate that T is the primary factor influencing shale deformation when P is low,while P is dominant under high P *** T<90℃ and P<60 MPa,shales undergo brittle deformation and their macropores decrease due to the compaction of primary pores,while mesopores increase because of the interconnection of *** 90℃200℃ and P>110 MPa,shales are subjected to ductile deformation,and their micro-and mesopores drop significantly due to the intense compaction in the matrix while macropores continuously increase with crack *** permeability of shale increases with the degree of deformation and ductile material contents are predicted to be a key factor determining whether open microcracks can be preserved after ductile *** account for these experimental results,an ideal model of micro pore-crack system evolution in deformed shales is further proposed,which can provide guidance for the exploration of shale gas resources in the deep or structurally complex zones.

关键词： Shale Deformation experiment Microscopic structure Pore-crack system Shale gas reservoir

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Dynamic defenses in cyber security:Techniques,methods and challenges Author links open overlay panel

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Digital Communications and Networks 2022年第4期8卷 422-435页

作者： Yu Zheng Zheng Li Xiaolong Xu Qingzhan Zhao School of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044JiangsuChina Key Laboratory for Novel Software Technology Nanjing UniversityNanjing210023JiangsuChina College of Information Science and Technology Shihezi University Geospatial Information Engineering Research CenterChina

Driven by the rapid development of the Internet of Things,cloud computing and other emerging technologies,the connotation of cyberspace is constantly expanding and becoming the fifth dimension of human ***,security problems in cyberspace are becoming serious,and traditional defense measures(e.g.,firewall,intrusion detection systems,and security audits)often fall into a passive situation of being prone to attacks and difficult to take effect when responding to new types of network attacks with a higher and higher degree of coordination and *** constructing and implementing the diverse strategy of dynamic transformation,the configuration characteristics of systems are constantly changing,and the probability of vulnerability exposure is ***,the difficulty and cost of attack are increasing,which provides new ideas for reversing the asymmetric situation of defense and attack in ***,few related works systematically introduce dynamic defense mechanisms for cyber *** related concepts and development strategies of dynamic defense are rarely analyzed and *** bridge this gap,we conduct a comprehensive and concrete survey of recent research efforts on dynamic defense in cyber ***,we firstly introduce basic concepts and define dynamic defense in cyber ***,we review the architectures,enabling techniques and methods for moving target defense and mimic *** is followed by taxonomically summarizing the implementation and evaluation of dynamic ***,we discuss some open challenges and opportunities for dynamic defense in cyber security.

关键词： Cyber security Dynamic defense Moving target defense Mimic defense

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Specification and counterexample generation for cyber-physical systems

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Soft Computing 2024年第17-18期28卷 9137-9155页

作者： Li, Zhen Cao, Zining Wang, Fujun Xing, Chao College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Jiangsu Nanjing211106 China Science and Technology on Electro-optic Control Laboratory Henan Luoyang471000 China Collaborative Innovation Center of Novel Software Technology and Industrializaton Nanjing University of Aeronautics and Astronautics Jiangsu Nanjing210023 China Key Laboratory of Safety-Critical Software Ministry of Industry and Information Technology Jiangsu Nanjing211106 China

Cyber-Physical Systems (CPS) are complex systems that integrate information control devices with physical resources, which can be automatically and formalized verified by model checking according to the expected requirements in the formal specification. The counterexamples in model checking are witnesses to the violation of the specification properties of the system and can provide important diagnostic information for debugging, controlling, and synthesizing CPS. Designing a rational specification language for CPS and generating effective counterexamples allows security vulnerabilities to be detected and addressed early in the system development. However, CPS involve frequent interactions between cyber and physical systems and often operate in unreliable environments, which poses new challenges for comprehensive modeling and designing specification languages for CPSs with discrete, continuous, time, probabilistic, and concurrent behaviors. Moreover, finding the smallest counterexample of CPS with probabilistic behavior in the shortest possible time has been identified as a Non-Deterministic Polynomial-complete (NP-complete) problem. Although a number of heuristics have been devised to address this challenge, the accuracy and efficiency of the solved counterexamples need to be improved due to the difficulty in determining the heuristic functions. We first provide a comprehensive model for CPS by introducing the Hybrid Probabilistic Time Labeled Transition System (HPTLTS). Subsequently, we design a specification language HPTLTS Temporal Logic (HPTLTS-TL) that can describe the properties of CPS. In addition, we propose an optimization algorithm CACO-A, which combines the Ant Colony Optimization (ACO) algorithm and the A-algorithm to efficiently generate the counterexample of CPS, which is represented as the diagnostic subgraph. Finally, we discuss a typical CPS example to demonstrate the feasibility of our approach. © The Author(s), under exclusive licence to Springer-

关键词： Embedded systems

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Safety decision of autonomous driving behavior based on Bayesian network and its verification method 24

Safety decision of autonomous driving behavior based on Baye...

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24th IEEE International Conference on Software Quality, Reliability and Security Companion, QRS-C 2024

作者： Li, Zexin Zhu, Yi Zhao, Li Zhao, Ying School of Computer Science and Technology Jiangsu Normal University Jiangsu Xuzhou China Nanjing University of Aeronautics and Astronautics Ministry of Industry and Information Technology Key Laboratory of Safety-Critical Software Jiangsu Nanjing China

ISBN: (纸本)9798350365658

With the increasing visibility of autonomous vehicles, the assurance of safe and precise behavioral decisions presents a substantial challenge within the realm of autonomous driving. The complexity of physical space, uncertainty in duration-space data, and human subjectivity complicate the assurance of existing behavior decision-making methods. To address these challenges, a safety decision method for autonomous driving based on Bayesian network is proposed. Firstly, semantic relations among risk elements in driving scenario are represented using knowledge graph, and the hierarchical structure and node information of the Bayesian network are determined based on expert knowledge and historical experience. Behavior decision actions are derived through Bayesian network inference. Secondly, leveraging the Bayesian network structure and inference results, a Duration-space Resource Timed Communicating Sequential process is construct to verify the security of time and space resources. Thirdly, the constructed process is converted into Bigraphs and use the CPS MODEL CHECKER for security verification. Finally, the effectiveness of the proposed method is verified using a highway lane change overtaking scenario. © 2024 IEEE.

关键词： Autonomous vehicles

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A Model-Agnostic Interpretability Approach Based on Enhanced Hierarchical Clustering 24

A Model-Agnostic Interpretability Approach Based on Enhanced...

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24th IEEE International Conference on Software Quality, Reliability and Security Companion, QRS-C 2024

作者： Ding, Xi Zhu, Yi Yu, Qiao Huang, Chongyang School of Computer Science and Technology Jiangsu Normal University Jiangsu Xuzhou China Nanjing University of Aeronautics and Astronautics Ministry of Industry and Information Technology Key Laboratory of Safety-Critical Software Jiangsu Nanjing China

ISBN: (纸本)9798350365658

The Local Interpretable Model-Agnostic Explanations (LIME) is a relatively novel technique for explaining black-box models. LIME generates perturbed instances of the model based on a random instance, and then approximates the original model with a linear model derived from the weighted perturbed instances, thereby providing an explanation for individual predictions. While LIME effectively addresses the opacity of black-box models, the randomness in instance generation often leads to unstable and inaccurate predictions. For a given prediction, different explanations may be generated, posing critical issues, particularly in security-sensitive domains. In response to these challenges, we propose a stable version of LIME, named DDLIME(Density and Distance-based LIME). DDLIME leverages improved hierarchical clustering and KNN algorithms to select instances that are most similar to the data, thus reducing the impact of perturbations. Additionally, the enhanced hierarchical clustering, incorporating density and distance metrics, enables DDLIME to address the limitations of traditional hierarchical clustering in clustering non-spherical clusters. Consequently, DDLIME can effectively capture complex structures and patterns within the data. The experimental results on three binary public datasets from the UCI repository demonstrate that DDLIME provides more stable explanations compared to LIME. Furthermore, compared to both baseline models, DDLIME exhibits superior performance across various evaluation metrics. © 2024 IEEE.

关键词： Hierarchical clustering

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A Dynamic Interest-Aware Message-Passing GCN for Recommendation 24

A Dynamic Interest-Aware Message-Passing GCN for Recommendat...

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24th IEEE International Conference on Software Quality, Reliability and Security Companion, QRS-C 2024

作者： He, Weichao Zhu, Yi Song, Mei Wu, Zixin Hao, Guosheng School of Computer Science and Technology Jiangsu Normal University Jiangsu Xuzhou China Jiangsu Engineering Technology Research Center of Ict in Education Jiangsu Xuzhou China Ministry of Industry and Information Technology Key Laboratory of Safety-Critical Software Jiangsu Nanjing China

ISBN: (纸本)9798350365658

Over the past few years, Graph Convolutional Networks (GCN) have emerged as a promising tool in the field of recommendation. They have the ability to effectively learn user and item embeddings by leveraging collaborative signals from higher-order neighbors. Nevertheless, the recommendation models based on GCN also face a common issue. As more layers are added, the node embeddings start to become increasingly similar and eventually become indistin-guishable, leading to a decline in performance. To address the issues at hand, we present a recommendation model called DIMP-GCN. This model utilizes a Dynamic Interest-aware Message-Passing approach, where users and interacted items are organized into distinct subgraphs based on their interests. Within each subgraph, single-layer graph convolution operations are performed. As a result, the users who have been updated are divided based on their interests once again, leading to dynamic changes in subgraph partitioning as the network layers stack. Nodes are able to acquire more accurate representations through this process. We conduct extensive experiments on three established datasets, showcasing the superior performance of our DIMP-GCN compared to other state-of-the-art GCN-based recommendation models. © 2024 IEEE.

关键词： Message passing

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Dual Radial-Resonant Wide Beamwidth Circular Sector Microstrip Patch Antennas

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Chinese Journal of Electronics 2023年第4期32卷 710-719页

作者： MAO Xiaohui LU Wenjun JI Feiyan XING Xiuqiong ZHU Lei Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Department of Electrical and Computer Engineering Faculty of Science and Technology University of Macau

In this article, a design approach to a radial-resonant wide beamwidth circular sector patch antenna is advanced. As properly evolved from a U-shaped d ipole, a prototype magnetic dipole can be fit in the radial direction of a circular sector patch radiator, with its length set as the positive odd-integer multiples of onequarter wavelength. In this way, multiple TM0m（m = 1,2,...） modes resonant circular sector patch antenna with short-circuited circumference and widened E-plane beamwidth can be realized by proper excitation and perturbations. Prototype antennas are then designed and fabricated to validate the design approach. Experimental results reveal that the E-plane beamwidth of a dual-resonant antenna fabricated on air/Teflon substrate can be effectively broadened to 128°/120°, with an impedance bandwidth of 17.4%/7.1%, respectively. In both cases, the antenna heights are strictly limited to no more than 0.03-guided wavelength. It is evidently validated that the proposed approach can effectively enhance the operational bandwidth and beamwidth of a microstrip patch antenna while maintaining its inherent low profile merit.

关键词： Geometry Patch antennas Perturbation methods Prototypes Magnetic resonance Microstrip antennas Bandwidth

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