检索结果-内蒙古大学图书馆

Fan-Beam Printed Full-Wave Dipole Antenna Array with Wide Bandwidth and Beamwidth

学校读者我要写书评

暂无评论

Fan-Beam Printed Full-Wave Dipole Antenna Array with Wide Ba...

Antennas and Propagation & USNC/URSI National Radio Science Meeting

作者： Zhiqi Ke Kwok Wa Leung Nan Yang School of Electronics and Information Technology (School of Microelectronics) and Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems Sun Yat-sen University Guangzhou China Department of Electrical Engineering State Key Laboratory of Terahertz and Millimeter Waves City University of Hong Kong Kowloon China Information and Communication Technology Centre CityU Shenzhen Research Institute Shenzhen China

ISBN: (数字)9798350369908

ISBN: (纸本)9798350369915

This paper presents a wideband, wide-beamwidth printed dipole antenna array. The electric field across the two horizontal arms of the printed dipole gives an equivalent magnetic dipole. This equivalent magnetic dipole and the printed dipole forms an magnetoelectric dipole, which has a wide bandwidth and a wide beamwidth. To further enhance the beamwidth, a full-wave printed dipole antenna instead of a halfwave printed dipole is used. Parasitic and shorting strips are deployed to obtain a uniform current distribution and thus, widen the beamwidth. To verify the idea, a 1×4 array is designed, fabricated, and measured. A 10-dB impedance bandwidth of 34% (20.85-29.35 GHz) and a peak 3-dB of $H$ -plane beamwidth of 192° at 25 GHz were measured.

关键词： Antenna measurements Impedance measurement Dipole antennas Magnetoelectric effects Bandwidth Gain measurement Current distribution

Radiation Pattern Decoupling Method of E-Plane-Coupled Patch Antennas

学校读者我要写书评

暂无评论

Radiation Pattern Decoupling Method of E-Plane-Coupled Patch...

International Symposium on Antennas, Propagation and EM Theory (ISAPE)

作者： Jingbiao Wu Nan Yang Kwok Wa Leuug School of Electronics and Information Technology and Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems Sun Yat-sen University Guangzhou China State Key Laboratory of Terahertz and Millimeter Waves and Department of Electrical Engineering City University of Hong Kong Hong Kong SAR China Information and Communication Technology Centre CityU shenzhen Research Institute Shenzhen China

ISBN: (数字)9798350353129

ISBN: (纸本)9798350353136

RPD E-plane-coupled patch antennas are presented in this article with radiation pattern decoupling (RPD) characteristics. Two patch elements are placed side by side, forming a whole patch radiator. To decouple the patch antennas, TM20 and TM30 modes are excited simultaneously, and their resonant frequencies are merged together by L-shaped slots and metallic vias. The L-shaped slots can not only adjust the resonant frequencies of the TM20 and TM30 modes, they also provide slot mode. The metallic vias are placed in the interface of patches to tune that of the TM20 mode. To verify the presented idea, a prototype is designed, fabricated, and measured for 2.4-GHz WLAN band. Good agreement can be observed between the measured and simulated results. The measured overlapping 10-dB impedance bandwidth is 6.9% (2.35-2.52 GHz), with a port isolation level of higher than 20 dB. Undistorted and symmetrical radiation patterns can be highlighted, showing good RPD effect.

关键词： Antenna measurements Wireless LAN Impedance measurement Antenna theory Patch antennas Resonant frequency Prototypes Bandwidth Impedance Antenna radiation patterns

Incentive Mechanism Design for Emergency Frequency control in Multi-Infeed Hybrid AC-DC System

学校读者我要写书评

暂无评论

arXiv 2022年

作者： Liu, Ye Shen, Chen Wang, Zhaojian Liu, Feng The State Key Laboratory of Power Systems Department of Electrical Engineering Tsinghua University Beijing100084 China The Key Laboratory of System Control and Information Processing Ministry of Education of China Department of Automation Shanghai Jiao Tong University Shanghai200240 China

In multi-infeed hybrid AC-DC (MIDC) systems, the emergency frequency control (EFC) with LCC-HVDC systems participating is of vital importance for system frequency stability. Nevertheless, when regional power systems are operated by different decision-makers, the LCC-HVDC systems and their connected AC systems might be unwilling to participate in the EFC due to the costs and losses. In this paper, to incentivize the LCC-HVDC systems and their connected adjacent AC systems to participate in the droop-based EFC, a novel control-parameter-based incentive mechanism is proposed, which can deal with various possible emergency frequency faults. Then, a non-cooperative-based incentive game model is formulated to implement the incentive mechanism in the MIDC system. An algorithm for seeking the Nash equilibrium is designed, and the uniqueness of Nash equilibrium is proven. Moreover, the individual rationality, incentive compatibility and social optimality of the proposed mechanism are analyzed and proven. The effectiveness of the proposed incentive mechanism is verified through a case study. Copyright © 2022, The Authors. All rights reserved.

关键词： Game theory

Pathological axonal enlargement in connection with amyloidosis,lysosome destabilization,and bleeding is a major defect in Alzheimer’s disease

学校读者我要写书评

暂无评论

Neural Regeneration Research 2026年第2期21卷 790-799页

作者： Hualin Fu Jilong Li Chunlei Zhang Guo Gao Qiqi Ge Xinping Guan Daxiang Cui Institute of Nano Biomedicine and Engineering School of Sensing Science and EngineeringSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghaiChina Institute of Marine Equipment Shanghai Jiao Tong UniversityShanghaiChina National Center for Translational Medicine Shanghai Jiao Tong UniversityShanghaiChina Department of Automation Shanghai Jiao Tong UniversityShanghaiChina The Key Laboratory of System Control and Information Processing Ministry of EducationShanghaiChina

Alzheimer’s disease is a multi-amyloidosis disease characterized by amyloid-βdeposits in brain blood vessels,microaneurysms,and senile *** amyloid-βdeposition affects axon pathology has not been examined *** used immunohistochemistry and immunofluorescence staining to analyze the forebrain tissue slices of Alzheimer’s disease *** axonal amyloidosis with distinctive axonal enlargement was observed in patients with Alzheimer’s *** average,amyloid-β-positive axon diameters in Alzheimer’s disease brains were 1.72 times those of control brain ***,axonal amyloidosis was associated with microtubule-associated protein 2 reduction,tau phosphorylation,lysosome destabilization,and several blood-related markers,such as apolipoprotein E,alpha-hemoglobin,glycosylated hemoglobin type A1C,and *** destabilization in Alzheimer’s disease was also clearly identified in the neuronal soma,where it was associated with the co-expression of amyloid-β,Cathepsin D,alpha-hemoglobin,actin alpha 2,and collagen type *** suggests that exogenous hemorrhagic protein intake influences neural lysosome ***,the data showed that amyloid-β-containing lysosomes were 2.23 times larger than control ***,under rare conditions,axonal breakages were observed,which likely resulted in Wallerian *** summary,axonal enlargement associated with amyloidosis,micro-bleeding,and lysosome destabilization is a major defect in patients with Alzheimer’s *** finding suggests that,in addition to the well-documented neural soma and synaptic damage,axonal damage is a key component of neuronal defects in Alzheimer’s disease.

关键词： Alzheimer’s disease amyloid-β amyloidosis axonal enlargement hemoglobin hemorrhage lysosome destabilization neuropil thread tau Wallerian degeneration

Semi-Global Leaderless Consensus of Linear Multi-agent systems with Actuator and Communication Constraints

学校读者我要写书评

暂无评论

Journal of systems Science & Complexity 2020年第4期33卷 882-902页

作者： WANG Jian SHI Liangren GUAN Xinping Department of Automation and Key Laboratory of System Control and Information Processing of Ministry of EducationShanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory of Navigation and Location-based Services and Academy of Information Technology and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

This paper studies the leaderless consensus problems of multi-agent systems with input saturation and intermittent communication over directed networks. Both the state feedback and the output feedback consensus algorithms are developed based on low gain feedback approach. The convergence of the trajectories of all agents can be achieved by these proposed algorithms, if the communication topology has a directed spanning tree, and the intermittent communication period T and time rate ρ are larger than their associated threshold values. Simulation examples are provided to verify the theoretical results.

关键词： agent directed communication

Distributed Emergency Frequency control Considering Transient Stability Constraints in Multi-Infeed Hybrid AC-DC System

学校读者我要写书评

暂无评论

arXiv 2022年

作者： Liu, Ye Shen, Chen Wang, Zhaojian The State Key Laboratory of Power Systems Department of Electrical Engineering Tsinghua University Beijing100084 China The Key Laboratory of System Control and Information Processing Ministry of Education of China Department of Automation Shanghai Jiao Tong University Shanghai200240 China

Due to possible emergency faults and frequency regulation reserve shortage in the multi-infeed hybrid AC-DC (MIDC) system, the emergency frequency control (EFC) with LCC-HVDC systems participating is important for system frequency stability. Nevertheless, the existing decentralized EFC strategies cannot guarantee the transient stability constraints of lines and cannot meet the frequency restoration requirement. To fill this gap, this paper proposes a complementary distributed EFC strategy. By selecting the semi-distributed or fully-distributed control law according to the state of AC system control center, the proposed distributed EFC can improve the control performance with a normal control center and enhance the control reliability in case of control center failure. Then, to derive the semi-distributed and fully-distributed control laws, a general design method is proposed by formulating an optimal EFC problem. Both of these two control laws can guarantee transient stability constraints, restore system frequency and achieve the defined optimal control objective. Moreover, the optimality of the closed-loop equilibrium is proven, and a Lyapunov analysis shows the asymptotic stability of the closed-loop system with the discontinuous control dynamics. A case study verifies the effectiveness of the proposed distributed EFC strategy. Copyright © 2022, The Authors. All rights reserved.

关键词： Asymptotic stability

Sensor-based Multi-agent Coverage control with Spatial Separation in Unstructured Environments

学校读者我要写书评

暂无评论

arXiv 2024年

作者： Wang, Xinyi Xu, Jiwen Gao, Chuanxiang Chen, Yizhou Zhang, Jihan Wang, Chenggang Ding, Yulong Chen, Ben M. Department of Mechanical and Automation Engineering The Chinese University of Hong Kong N.T. Shatin Hong Kong Department of Automation Key Laboratory of System Control and Information Processing Ministry of Education of China Shanghai Jiao Tong University Shanghai200240 China Department of Control Science and Engineering Tongji University Shanghai China Frontiers Science Center for Intelligent Autonomous Systems Ministry of Education China

Multi-robot systems have increasingly become instrumental in tackling coverage problems. However, the challenge of optimizing task efficiency without compromising task success still persists, particularly in expansive, unstructured scenarios with dense obstacles. This paper presents an innovative, decentralized Voronoi-based coverage control approach to reactively navigate these complexities while guaranteeing safety. This approach leverages the active sensing capabilities of multi-robot systems to supplement GIS (Geographic information System), offering a more comprehensive and real-time understanding of environments like post-disaster. Based on point cloud data, which is inherently non-convex and unstructured, this method efficiently generates collision-free Voronoi regions using only local sensing information through spatial decomposition and spherical mirroring techniques. Then, deadlock-aware guided map integrated with a gradient-optimized, centroid Voronoi-based coverage control policy, is constructed to improve efficiency by avoiding exhaustive searches and local sensing pitfalls. The effectiveness of our algorithm has been validated through extensive numerical simulations in high-fidelity environments, demonstrating significant improvements in task success rate, coverage ratio, and task execution time compared with others. Copyright © 2024, The Authors. All rights reserved.

关键词： Multipurpose robots

SAD-TIME: a Spatiotemporal-fused network for depression detection with Automated multi-scale Depth-wise and TIME-interval-related common feature extractor

学校读者我要写书评

暂无评论

arXiv 2024年

作者： Wang, Han-Guang Hou, Hui-Rang Jin, Li-Cheng Xu, Chen-Yang Zhang, Zhong-Yi Meng, Qing-Hao Zhang, Yong-Hui Tianjin Key Laboratory of Process Measurement and Control Institute of Robotics and Autonomous Systems School of Electrical and Information Engineering Tianjin University Tianjin300072 China Department of Psychiatry Tianjin Anding Hospital Mental Health Center Tianjin Medical University China

Background and Objective: Depression is a severe mental disorder, and accurate diagnosis is pivotal to the cure and rehabilitation of people with depression. However, the current questionnaire-based diagnostic methods could bring subjective biases and may be denied by subjects. In search of a more objective means of diagnosis, researchers have begun to experiment with deep learning-based methods for identifying depressive disorders in recent years. Methods: In this study, a novel Spatiotemporal-fused network with Automated multi-scale Depth-wise and TIME-interval-related common feature extractor (SAD-TIME) is proposed. SAD-TIME incorporates an automated nodes’ common features extractor (CFE), a spatial sector (SpS), a modified temporal sector (TeS), and a domain adversarial learner (DAL). The CFE includes a multiscale depth-wise 1D-convolutional neural network and a time-interval embedding generator, where the unique information of each channel is preserved. The SpS fuses the functional connectivity with the distance-based connectivity containing spatial position of EEG electrodes. A multi-head-attention graph convolutional network is also applied in the SpS to fuse the features from different EEG channels. The TeS is based on long short-term memory and graph transformer networks, where the temporal information of different time-windows is fused. Moreover, the DAL is used after the SpS to obtain the domain-invariant feature. Results: Experimental results under tenfold cross-validation show that the proposed SAD-TIME method achieves 92.00% and 94.00% depression classification accuracies on two datasets, respectively, in cross-subject mode. Conclusion: SAD-TIME is a robust depression detection model, where the automatedly-generated features, the SpS and the TeS assist the classification performance with the fusion of the innate spatiotemporal information in the EEG signals. Copyright © 2024, The Authors. All rights reserved.

关键词： Convolutional neural networks

AnyBipe: An End-to-End Framework for Training and Deploying Bipedal Robots Guided by Large Language Models

学校读者我要写书评

暂无评论

arXiv 2024年

作者： Yao, Yifei He, Wentao Gu, Chenyu Du, Jiaheng Tan, Fuwei Zhu, Zhen Lu, Junguo All authors are with Machine Vision and Autonomous System Laboratory Department of Automation School of Electrical Information and Electronic Engineering Shanghai Jiao Tong University Shanghai China Key Laboratory of System Control and Information Processing Ministry of Education of China China Shanghai Engineering Research Center of Intelligent Control and Management Shanghai200240 China University of Michigan Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong University Shanghai China

Training and deploying reinforcement learning (RL) policies for robots, especially in accomplishing specific tasks, presents substantial challenges. Recent advancements have explored diverse reward function designs, training techniques, simulation-to-reality (sim-to-real) transfers, and performance analysis methodologies, yet these still require significant human intervention. This paper introduces an end-to-end framework for training and deploying RL policies, guided by Large Language Models (LLMs), and evaluates its effectiveness on bipedal robots. The framework consists of three interconnected modules: an LLM-guided reward function design module, an RL training module leveraging prior work, and a sim-to-real homomorphic evaluation module. This design significantly reduces the need for human input by utilizing only essential simulation and deployment platforms, with the option to incorporate human-engineered strategies and historical data. We detail the construction of these modules, their advantages over traditional approaches, and demonstrate the framework’s capability to autonomously develop and refine controlling strategies for bipedal robot locomotion, showcasing its potential to operate independently of human intervention. Copyright © 2024, The Authors. All rights reserved.

关键词： Reinforcement learning