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arXiv 2020年

作者： Shen, Tong Cai, Wenlong Lin, Yan Zhang, Shuo Lin, Jinyong Shu, Feng Wang, Jiangzhou The School of Information and Computer Anhui Agriculture University 230036 China The School of Electronic and Optical Engineering Nanjing University of Science and Technology 210094 China The National Key Laboratory of Science and Technology on Aerospace Intelligence Control Beijing Aerospace Automatic Control Institute Beijing100854 China School of Information and Communication Engineering HaiNan University Hainan 570228 China The School of Engineering and Digital Arts University of Kent CanterburyCT2 7NT United Kingdom

In this paper, multiple reconfigurable intelligent surfaces (RIS) aided secure precise wireless transmission (SPWT) schemes are proposed in the three-dimensional (3D) wireless communication scenario. Unavailable direct path channels from transmitter to receivers are considered when the direct paths are obstructed by obstacles. Then, multiple RISs are utilized to achieve SPWT through the reflection path among transmitter, RISs and receivers in order to enhance the communication performance and energy efficiency simultaneously. First, a maximum-signal-to-interference-and-noise ratio (MSINR) scheme is proposed in a single user scenario. Then, the multi-user scenario is considered where the illegitimate users are regarded as eavesdroppers. A maximum-secrecy-rate (MSR) scheme and a maximum-signal-to-leakage-and-noise ratio (MSLNR) are proposed. The former achieves a better secrecy rate (SR) performance but incurs a higher complexity. The latter has a lower complexity than the MSR scheme with an SR performance loss. Simulation results show that both single-user scheme and multi-user scheme can achieve SPWT which transmits confidential message precisely to location of desired users. Moreover, MSLNR scheme has a lower complexity than the MSR scheme, while the SR performance is close to that of the MSR scheme. © 2020, CC0.

关键词： Transmitters

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Computer-aided diagnosis for Diabetic Retinopathy based on Firefly algorithm

Computer-aided diagnosis for Diabetic Retinopathy based on F...

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International Conference on Advanced Computing, ICAC

作者： B. Keerthiveena T. Veerakumar S. Esakkirajan Badri Narayan Subudhi Department of Instrumentation and Control Systems Engineering PSG College of Technology Coimbatore India Department of Electronics and Communication Engineering National Institute of Technology Goa India Department of Electrical Engineering Indian Institute of Technology Jammu India

ISBN: (数字)9781728152868

ISBN: (纸本)9781728152875

Diabetic retinopathy is a diabetes complication that has been a leading cause of blindness worldwide. Segmentation of blood vessels and detection of exudates in fundus images through an automated system will help the ophthalmologist to provide a proper treatment that may cure or decrease the severity of the retinal diseases. Realizing its significance, a diabetic retinopathy screening system was proposed in this paper which classifies normal from the abnormal fundus image. Segmentation of blood vessel is based on match filter followed by fuzzy c-means clustering. The small and thin vessels were obtained from directional filter bank by incorporating the use of line-like directional features. In this study a combination of both statistical and geometric features were extracted from image regions. A firefly algorithm for discriminative feature selection for the early detection of diabetic retinopathy was proposed. Publically available dataset such as DRIVE, HRF, DIAREDB1, MESSIDOR and one local dataset are used to validate the suggested system. Moreover, the proposed algorithm has been compared with few state-of-the-art techniques such as particle swarm optimization, genetic algorithm and ant colony optimization. The results demonstrated that the proposed method improves the classification accuracy with a minimized feature set for the early detection of diabetic retinopathy.

关键词： Diabetes Blood vessels Biomedical imaging Retinopathy Feature extraction Retina Filter banks

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Kinematic feature-based evaluation method for elderly balance ability by using factor analysis 1

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2nd Chinese Conference on Pattern Recognition and Computer Vision, PRCV 2019

作者： Ming, Rui Xing-Rong, Fan Xu, Guoliang Chongqing Engineering Laboratory for Detection Control and Integrated System Chongqing Technology and Business University Chongqing400067 China College of Communication and Information Engineering Chongqing University of Posts and Telecommunications Chongqing400065 China Electronic Information and Networking Research Institute Chongqing University of Posts and Telecommunications Chongqing400065 China

ISBN: (数字)9783030317263

ISBN: (纸本)9783030317256

Modeling and assessing balance ability for elderly people is an important and realistic task with a view to assisting them in mobility status, correcting postures and preventing accidental falling. The aim of this study was to develop a novel kinematic feature-based evaluation method for elderly balance ability by using factor analysis. Based on the kinematics, twenty-five feature indicators were first extracted from walking gait data, which were collected by deploying twenty-four monitoring points on the body of the elderly subjects. Then, two main factors were identified by using factor analysis that affect the walking balance ability of the elderly, and the comprehensive evaluation scoring model of the elderly balance ability was constructed. Finally, real data from all the elderly subjects in free walking state were used to validate our method. The results of empirical analysis confirm the validity and usefulness of the proposed method. © Springer Nature Switzerland AG 2019.

关键词： Kinematics

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Research on the Influence of Non-Conductor on the Weight Function of Electromagnetic Flowmeter

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Journal of Physics: Conference Series 2021年第3期1952卷

作者： Xuejing Li Lijun Sun Shanghai Institute of Measurement and Testing Technology Shanghai 201203 China Shanghai Key Laboratory of On-line Testing and Control Technology Shanghai 201203 China School of Electrical and Information Engineering Tianjin University Tianjin 300072 China.

The demand for multiphase flow measurement is widespread in petrochemical and other fields. Due to its small size, easy maintenance, and no moving parts, electromagnetic flowmeters are widely used in single fluid measurement. With the increasing application of traditional electromagnetic flowmeters in petrochemical and other fields, the problems of traditional electromagnetic flowmeters in multiphase flow measurement applications have been discovered. How to optimize the structure of the electromagnetic flowmeter and how to improve the measurement accuracy has become a new research focus. On the basis of a large number of literature studies, this research is based on the finite element method, and systematically studies the influence of multiphase flow on the weight function of electromagnetic flowmeters. Firstly, modeling the existence of non-conductive objects in the electromagnetic flowmeter. Secondly, analyze the weight function characteristics of the non-conductive objects on the electromagnetic flowmeter from two angles of different radii and different positions. The conclusions of this study can provide a certain reference basis for the electromagnetic flowmeter in the measurement of multiphase flow.

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Ultra-wideband dual-layer magnetic absorber with active impedance matching

Ultra-wideband dual-layer magnetic absorber with active impe...

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2019 Photonics and Electromagnetics Research Symposium - Fall, PIERS - Fall 2019

作者： Hu, Wei Li, Jian Huang, Yongjun Wen, Guangjun Zhang, Haobin Zheng, Wenxian Yang, Yongjun Gu, Weiwei Inserra, Daniele Xu, Zhengwu Li, Gui Zhang, Dongliang University of Electronic Science and Technology of China School of Information and Communication Engineering Chengdu611731 China Science and Technology on Electronic Information Control Laboratory Chengdu610036 China Tsinghua Shenzhen International Graduate School Shenzhen518055 China University of Electronic Science and Technology of China Yibin Intelligent Information System Institute Yibin644005 China

ISBN: (纸本)9781728153049

A novel broadband absorber is designed in this paper, which consists of two layers of magnetic materials and metal reflector. In order to achieve broadband performance, the upper layer and the lower layer magnetic material are designed into periodically cylindrically holes with performance multi-resonance frequency. The simulations showed that an absorption more than 90% for normal incident is obtained in the frequency range from 1.62GHz to 18GHz. The absorber has polarization insensitivity when the incident electromagnetic wave is obliquely with TE/TM polarization, and the absorbing is stable within 0-60 degrees incident. The absorber has potential application in radar system and RCS reduced. © 2019 IEEE.

关键词： Ultra-wideband (UWB)

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Observer-Based Adaptive Multi-dimensional Taylor Network control for Nonlinear Systems with Time-Delay

Observer-Based Adaptive Multi-dimensional Taylor Network Con...

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Data Driven control and Learning Systems (DDCLS)

作者： Lei Chu Shuhua Zhang Mingxin Wang Shanliang Zhu Yuqun Han School of Mathematics and Physics Qingdao University of Science and Technology Qingdao P. R. China The Research Institute for Mathematics and Interdisciplinary Sciences Qingdao University of Science and Technology Qingdao China College of Electromechanical Engineering Qingdao University of Science and Technology Qingdao P. R. China Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of Education Nanjing P. R. China

ISBN: (数字)9781728159225

ISBN: (纸本)9781728159232

In this paper, an observer-based adaptive Multi-dimensional Taylor network (MTN) controller is proposed for strictly feedback nonlinear systems with time-delay and unmeasurable states. MTNs are utilized to approximate the unknown and desired control input signals directly instead of the unknown nonlinear functions. Moreover, a linear state observer is designed for estimating the unmeasured states. Based on the backstepping technique, a novel adaptive MTN control strategy with simple structure and good real time property is proposed. The designed controller can guarantee all the signals of the closed-loop system are bounded and the tracking error converges to a small neighborhood of the origin. Simulation results are given to demonstrate the effectiveness of the proposed method.

关键词： Nonlinear systems Backstepping Observers Closed loop systems Artificial neural networks Adaptive control Stability analysis

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Study on growth mechanism of InAs array nanowires on two different patterned substrates

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Vacuum 2025年 240卷

作者： Xiaoye Wang Xiaoguang Yang Tao Yang College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou 730050 People's Republic of China Key Laboratory of Gansu Advanced Control for Industrial Processes Lanzhou University of Technology Lanzhou 730050 People's Republic of China Modern Industry College of Microelectronics Lanzhou University of Technology Lanzhou 730050 People's Republic of China Laboratory of Nanoscale Semiconductor Measurement Lanzhou University of Technology Lanzhou 730050 People's Republic of China Key Laboratory of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences P.O. Box 912 Beijing 100083 People's Republic of China College of Materials Science and Optoelectronic Technology University of Chinese Academy of Sciences Beijing 100049 People's Republic of China

Si/SiO 2 patterned substrates are usually employed to assist the positioning growth of array nanowires, but the detailed growth mechanism has not been thoroughly investigated. In this work, two completely different methods were adopted to fabricate Si/SiO 2 patterned substrates, and the InAs array nanowires grown on them via MOCVD presented some distinct growth results. By deeply analyzing the different processes and structures of the two methods for preparing patterned substrates, the different growth mechanisms of the two array nanowires were studied. Moreover, the method of preparing Si/SiO 2 patterned substrates using Si 3 N 4 as a transition layer can further reduce the diameter of naonholes and solve the problem that the diameter of nanoholes of the Si/SiO 2 patterned substrates prepared by the traditional method is difficult to be further reduced.

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Highly efficient storage of cavity SPDC single photons in room temperature gradient echo memory

APL Quantum

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APL Quantum 2024年第3期1卷

作者： Anthony C. Leung W. Y. Sarah Lau Aaron D. Tranter Karun V. Paul Markus Rambach Ben C. Buchler Ping Koy Lam Andrew G. White Till J. Weinhold ARC Centre of Excellence for Quantum Computation and Communication Technology Sydney NSW 2052 Australia Department of Quantum Science and Technology Research School of Physics The Australian National University Acton ACT 2601 Australia Quantum Measurement Lab Blackett Laboratory Imperial College London London SW7 2BW United Kingdom ARC Centre of Excellence for Engineered Quantum Systems Brisbane QLD 4072 Australia School of Maths and Physics University of Queensland Brisbane QLD 4072 Australia Institute of Materials Research and Engineering Agency for Science Technology and Research (ASTAR) 2 Fusionopolis Way 08-03 Innovis 138634 Singapore

Efficient quantum memories will be an essential building block of large-scale networked quantum systems and provide a link between flying photonic qubits and atomic or quasi-atomic local quantum processors. Memory efficiencies above 50% are required to be operating above the quantum no-cloning limit. High efficiency operation necessitates tailored photon source and memory pairs with matched bandwidths. In this paper, we explore the combination of an ultralow spectral bandwidth source of single photons from cavity-enhanced spontaneous parametric down-conversion with a hot gas-ensemble atomic memory. Our rubidium vapor gradient echo memory achieves 84% ± 3% recall efficiency of single photons: a record for single photon storage in a warm vapor platform that avoids bulky and complex systems, such as high vacuum and low temperature cryogenics.

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Sparse photoacoustic microscopy reconstruction based on matrix nuclear norm minimization 2nd

Sparse photoacoustic microscopy reconstruction based on matr...

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2nd International Conference on Machine Learning and Intelligent communications, MLICOM 2017

作者： Fu, Ying Feng, Naizhang Shi, Yahui Liu, Ting Sun, Mingjian Department of Control Science and Engineering Harbin Institute of Technology at Weihai Weihai264209 China Department of Measurement and Control Technology and Instrumentation Dalian Maritime University Dalian116026 China

ISBN: (纸本)9783319735634

As a high-resolution deep tissue imaging technology, photoacoustic microscopy (PAM) is attracting extensive attention in biomedical studies. PAM has trouble in achieving real-time imaging with the long data acquisition time caused by point-to-point sample mode. In this paper, we propose a sparse photoacoustic microscopy reconstruction method based on matrix nuclear norm minimization. We use random sparse sampling instead of traditional full sampling and regard the sparse PAM reconstruction problem as a nuclear norm minimization problem, which is efficiently solved under alternating direction method of multiplier (ADMM) framework. Results from PAM experiments indicate the proposed method could work well in fast imaging. The proposed method is also be expected to promote the achievement of PAM real-time imaging. © ICST institute for Computer Sciences, Social Informatics and Telecommunications engineering 2018.

关键词： Data acquisition

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Publisher Correction: Reservoir characteristics and logging evaluation of gas - bearing mudstone in the south of North China Plain

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Scientific reports 2020年第1期10卷 19572页

作者： Liang Liu Heping Pan Zhenzhou Lin Shihui Zhang Zhen Qin Jianwei Li Guoshu Huang Lei Wang Dong Li Institute of Geophysics and Geomatics China University of Geosciences (Wuhan) Wuhan 430074 China. Institute of Geophysics and Geomatics China University of Geosciences (Wuhan) Wuhan 430074 China. panpinge@***. Institute of Geophysical and Geochemical Exploration CAGS Langfang 065000 China. linzz81@***. School of Geophysics and Measurement-Control Technology East China University of Technology Nanchang 330013 China. Well Logging Company of Sinopec North China Petroleum Engineering Company Zhengzhou 450007 China.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

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