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Energy Localization in Spherical Non-Hermitian Topolectrical Circuits

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arXiv 2024年

作者： Shen, Xizhou Wang, Xiumei Guo, Haotian Zhou, Xingping College of Integrated Circuit Science and Engineering Nanjing University of Posts and Telecommunications Nanjing210003 China College of Electronic and Optical Engineering Nanjing University of Posts and Telecommunications Nanjing210003 China School of Design Arts and Media Nanjing University of Science and Technology Nanjing China Institute of Quantum Information and Technology Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing210003 China

This work delves into the energy localization in non-Hermitian systems, particularly focusing on the effects of topological defects in spherical models. We analyze the mode distribution changes in non-Hermitian Su-Schrieffer-Heeger (SSH) chains impacted by defects, utilizing the Maximum Skin Corner Weight (MaxWSC). By introducing an innovative spherical model, conceptualized through bisecting spheres into one-dimensional chain structures, we investigate the non-Hermitian skin effect (NHSE) in a new dimensional context, venturing into the realm of non-Euclidean geometry. Our experimental validations on Printed Circuit Boards (PCBs) confirm the theoretical findings. Collectively, these results not only validate our theoretical framework but also demonstrate the potential of engineered circuit systems to emulate complex non-Hermitian phenomena, showcasing the applicability of non-Euclidean geometries in studying NHSE and topological phenomena in non-Hermitian systems. © 2024, CC BY.

关键词： Printed circuit boards

A Secure and Efficient Multi-Object Grasping Detection Approach for Robotic Arms

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arXiv 2022年

作者： Wang, Hui Cheng, Jieren Xu, Yichen Ni, Sirui Yang, Zaijia Li, Jiangpeng School of Computer Science and Technology School of Information and Communication Engineering Hainan University Haikou China RobAI-Lab Hainan University Haikou China

Robot grasping is one of the most important abilities of modern intelligent robots, especially industrial robots. However, most of the existing robot arm’s grasp detection work is highly dependent on their edge computing ability, and the safety problems in the process of grasp detection are not considered enough. In this paper, we propose a new robotic arm grasping detection model with an edge-cloud collaboration method. With the scheme of multi-object multi-grasp, our model improves the mission success ratio of grasping. The model can not only complete the compression of full-resolution images but also achieve image compression at a limited bit rate. The image compression ratio reaches 2.03%, the structural difference value is higher than 0.91, and our average detection speed reaches 13.62fps. Furthermore, we have packaged our model as a functional package of the ROS operating system, which can be easily used in actual robotic arm operations. Our solution can be fully applied to other work of robots to promote the development of the field of robotics. © 2022, CC BY.

关键词： Robotic arms

Globally-Optimal Contrast Maximisation for Event Cameras

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arXiv 2022年

作者： Peng, Xin Gao, Ling Wang, Yifu Kneip, Laurent The Mobile Perception Lab of School of Information Science and Technology ShanghaiTech University The Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences University of Chinese Academy of Sciences China The Mobile Perception Lab of School of Information Science and Technology ShanghaiTech University China The Shanghai Engineering Research Center of Intelligent Vision and Imaging China The Australian National University Australia

Event cameras are bio-inspired sensors that perform well in challenging illumination conditions and have high temporal resolution. However, their concept is fundamentally different from traditional frame-based cameras. The pixels of an event camera operate independently and asynchronously. They measure changes of the logarithmic brightness and return them in the highly discretised form of time-stamped events indicating a relative change of a certain quantity since the last event. New models and algorithms are needed to process this kind of measurements. The present work looks at several motion estimation problems with event cameras. The flow of the events is modelled by a general homographic warping in a space-time volume, and the objective is formulated as a maximisation of contrast within the image of warped events. Our core contribution consists of deriving globally optimal solutions to these generally non-convex problems, which removes the dependency on a good initial guess plaguing existing methods. Our methods rely on branch-and-bound optimisation and employ novel and efficient, recursive upper and lower bounds derived for six different contrast estimation functions. The practical validity of our approach is demonstrated by a successful application to three different event camera motion estimation problems. Copyright © 2022, The Authors. All rights reserved.

关键词： Motion estimation

An Object Reconstruction Method Based on Point Cloud with Range Camera 2021

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An Object Reconstruction Method Based on Point Cloud with Ra...

2nd International Conference on Computing and Data science, CONF-CDS 2021

作者： Yan, Sunchao Yi, Jianjun Ding, Hongkai Wang, Danwei Zhao, Changchun Department of Mechanical Engineering East China University of Science and Technology Shanghai200237 China Intelligent Unmanned System Control Technology Joint Lab Shanghai201109 China School of Electrical and Electronic Engineering Nanyang Technological University Singapore639798 Singapore Shanghai Aerospace Control Technology Institute Shanghai201109 China

ISBN: (纸本)9781450389570

We present an object reconstruction approach based on point cloud. To accurately estimate sensor pose, a combination of frame-to-frame registration and frame-to-model registration is used in our approach with integration to produce the model of reconstructed object. The global optimization used in the approach distributes residual registration errors through the sensor trajectory. Our results demonstrate that the approach is fast and robust to reconstruct objects with a consumer-grade range camera. © 2021 ACM.

关键词： Global optimization

Machine Learning Based Early Prediction of Parkinson's Disease for Sustainable Healthcare 1st

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Machine Learning Based Early Prediction of Parkinson's Disea...

1st International Conference on Sustainable Development through Machine Learning, Artificial Intelligence, and IoT, ICSD 2023

作者： Chauhan, Ritu Mehta, Khushi Alankar, Bhavya Kaur, Harleen Artificial Intelligence and IoT Lab Center for Computational Biology and Bioinformatics Amity University UP Noida India Amity Institute of Information Technology Amity University UP Mumbai India Department of Computer Science and Engineering School of Engineering Sciences and Technology Jamia Hamdard New Delhi India

ISBN: (纸本)9783031470547

The healthcare sector and technology are working hand-in-hand, which has led researchers to focus on Parkinson's disease. In a world where medical science and technology intertwined, there was a group of researchers determined to unravel the mysteries of Parkinson's disease. Medical science with machine learning algorithms, aimed to develop a robust prediction model for diagnosing this complex neurological disorder. The researchers explored various algorithms including Xgboost, Naive Bayes, Tree Classifier, KNN model, SVC model, Logistic Model, Random Forest, AdaBoost, and Gradient Boosting, using a diverse dataset encompassing clinical measurements, genetic information, and demographic factors. The researchers utilized various machine learning algorithms to uncover patterns and correlations, shed light on relationships, make accurate predictions, foster insights, differentiate Parkinson's disease, understand odds and probabilities, tackle uncertainty, and improve accuracy. By combining these algorithms, they constructed a prediction model for the accurate diagnosis of Parkinson's disease, bringing us closer to unraveling its mysteries. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

关键词： Adaptive boosting

Seamless maps of major elements of the Moon:Results from high-resolution geostationary satellite

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Research in Astronomy and Astrophysics 2021年第2期21卷 52-60页

作者： Yu Lu Yun-Zhao Wu Cui Li Jin-Song Ma Wen-Wen Qi Wei Tan Xiao-Man Li Zhi-Cheng Shi Hong-Yan He Shu-Wu Dai Guo Li Feng-Jing Liu Jing-Qiao Wang Xiao-Yan Wang Qi Wang Ling-Jie Meng Key Laboratory of Planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210034China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Hefei 230026China Space Science Institute Macao University of Science and TechnologyMacaoChina School of Geography and Ocean Science Nanjing UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China Beijing Institute of Space Mechanics and Electricity Beijing 100076China Beijing Institute of Spacecraft System Engineering Beijing 100076China China Centre for Resources Satellite Data and Application Beijing 100094China Earth Observation System and Data Center China National Space AdministrationBeijing 100010China

Major elements such as Fe,Ti,Mg,Al,Ca and Si play very important roles in understanding the origin and evolution of the *** maps of these major elements derived from orbital data are based on mosaic images or low-resolution gamma-ray *** hue variations and gaps among orbital boundaries in the mosaic images are not conducive to geological *** paper aims to produce seamless and homogenous distribution maps of major elements using the single-exposure image of the whole lunar disk obtained by China’s high-resolution geostationary satellite,Gaofen-4,with a spatial resolution of500 *** elemental contents of soil samples returned by Apollo and Luna missions are regarded as ground truth,and are correlated with the reflectance of the sampling sites extracted from Gaofen-4 *** final distribution maps of these major oxides are generated with the statistical regression *** these products,the average contents and proportions of the major elements for maria and highlands were estimated and *** results showed that Si O2 and Ti O2 have the highest and lowest fractions in mare and highland areas,***,the relative concentrations of these elements could serve as indicators of geologic processes,e.g.,the obviously asymmetric distributions of Al2 O3,Ca O and Si O2 around Tycho crater may suggest that Tycho crater was formed by an oblique impact from the southwest direction.

关键词： Moon-Data analysis-Imaging spectroscopy

Ultrawideband Dual-polarized Magneto-electric Dipole Antenna With High Isolation

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Ultrawideband Dual-polarized Magneto-electric Dipole Antenna...

Cross Strait Quad-Regional Radio science and Wireless technology Conference (CSRWTC)

作者： Yongmao Wang Liangliang Zhao Jiaping Hou Mingxuan Zheng Chuwei Li Aidong Li Chufeng Hu Tao Ma Huiling Zhao School of Electronics and Information Northwestern polytechnical university (NPU) Xi'an China AVIC SHAANXI AERO ELECTRIC CO. LTD System Engineering Division Xi'an Electronic Engineering Research Institute Xi'an China China Academy of Space Technology (CAST) Beijing China Science and Technology on UAV Laboratory Northwestern Polytechnic University (NPU) Xi'an China The 43rd Research Institute of CETC Hefei China

ISBN: (数字)9798331507794

ISBN: (纸本)9798331507800

In this manuscript, an ultrawideband (UWB) dual-polarized magneto-electric (ME) dipole antenna with high isolation was presented which consists of a crossed ME dipole, two orthogonal arch-shaped feeding probes and eight groups of parasitic resonant units loaded on the hexagonal floor. The parasitic resonant units loaded around the main radiator of the antenna realize the impedance matching at lower frequencies, introducing a resonance point to enable the antenna to operate at lower frequencies. Besides, by etching crossed rectangular slots on the electric dipoles, the current path is effectively extended, allowing the antenna to operate at higher frequencies. Concurrently, by using orthogonal arch-shaped feeding probes, high isolation is achieved. As a result, the simulation results indicate that the designed antenna achieves an impedance bandwidth of 110.82%, ranging from 1.03 to 3.59 GHz with a high isolation of better than 31.7 dB.

关键词： Dipole antennas Simulation Magnetoelectric effects Magnetic resonance Antenna feeds Ultra wideband antennas Impedance Probes Loaded antennas Floors

Hierarchical Osteoporosis Screening Model for Middle and Elderly Women: Integrating Genetic Feature Generation with Catboost-Tabnet

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SSRN

SSRN 2023年

作者： Wu, Yingfei Li, Jinming Chen, Yijie Zhang, Yichao Yuan, Zhenming Sun, Xiaoyan Yu, Kai Zhang, Zhifen School of Information Science and Technology Hangzhou Normal University Hangzhou310016 China Hangzhou Zhejiang 310008 China Engineering Research Center of Mobile Health Management System Ministry of Education Hangzhou Normal University School of Public Health Hangzhou311121 China

Osteoporosis, a prevalent metabolic bone disease, poses a significant concern in China, particularly among women aged 50 and above. The latest data indicates a 32.1% prevalence in this demographic, rising to 51.6% for those aged 65 and above. Early-stage osteoporosis often lacks symptoms, leading to diagnoses post-fracture. Although dual-energy X-ray absorptiometry (DXA) is the gold standard, its limited usage necessitates alternative identification methods, particularly for middle-aged and elderly *** study aims to create a convenient and accurate tool for early osteoporosis detection in this demographic, utilizing the CatBoost-TabNet hierarchical screening model. Integrating personal health and clinical laboratory features, the model incorporates feature selection from multiple models and a genetic feature generation *** two-layered hierarchical screening model assesses risks comprehensively. The first layer identifies potential osteoporosis risk swiftly with easily accessible health-related features, achieving 90.01% accuracy, 80.40% sensitivity, and 93.4% specificity. The second layer, using medical test data and first-layer outcomes, enhances reliability, yielding 94.58% accuracy, 89.11% sensitivity, and 96.34% specificity. Outperforming the Osteoporosis Self-Assessment Tool for Asians (OSTA), this approach demonstrates robust performance. Additionally, the model incorporates SHAP analysis, further enhancing *** conclusion, this study's framework shows practical application and potential advancement, providing valuable insights for early osteoporosis detection in middle-aged and elderly women. © 2023, The Authors. All rights reserved.

关键词： Diseases

Trajectory and Power Design for Aerial CRNs with Colluding Eavesdroppers

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arXiv 2023年

作者： Lei, Hongjiang Jiang, Jiacheng Yang, Haosi Park, Ki-Hong Ansari, Imran Shafique Pan, Gaofeng Alouini, Mohamed-Slim The School of Communications and Information Engineering Chongqing University of Posts and Telecommunications Chongqing400065 China Chongqing Key Lab of Mobile Communications Technology Chongqing400065 China Bharath Institute of Science and Technology Chennai600073 India The School of Cyberspace Science and Technology Beijing Institute of Technology Beijing100081 China Thuwal23955-6900 Saudi Arabia

Unmanned aerial vehicles (UAVs) can provide wireless access services to terrestrial users without geographical limitations and will become an essential part of the future communication system. However, the openness of wireless channels and the mobility of UAVs make the security of UAV-based communication systems particularly challenging. This work investigates the security of aerial cognitive radio networks (CRNs) with multiple uncertainties colluding eavesdroppers. A cognitive aerial base station transmits messages to cognitive terrestrial users using the spectrum resource of the primary users. All secondary terrestrial users and illegitimate receivers jointly decode the received message. The average secrecy rate of the aerial CRNs is maximized by jointly optimizing the UAV's trajectory and transmission power. An iterative algorithm based on block coordinate descent and successive convex approximation is proposed to solve the non-convex mixed-variable optimization problem. Numerical results verify the effectiveness of our proposed algorithm and show that our scheme improves the secrecy performance of airborne CRNs. © 2023, CC BY.

关键词： Antennas