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Improvement for Testing the Gravitational Inverse-Square Law at the Submillimeter Range

Physical Review Letters 2020年第5期124卷 051301-051301页

作者： Wen-Hai Tan An-Bin Du Wen-Can Dong Shan-Qing Yang Cheng-Gang Shao Sheng-Guo Guan Qing-Lan Wang Bi-Fu Zhan Peng-Shun Luo Liang-Cheng Tu Jun Luo MOE Key Laboratory of Fundamental Physical Quantities Measurement & Hubei Key Laboratory of Gravitation and Quantum Physics PGMF and School of Physics Huazhong University of Science and Technology Wuhan 430074 People’s Republic of China TianQin Research Center for Gravitational Physics and School of Physics and Astronomy Sun Yat-sen University (Zhuhai Campus) Zhuhai 519082 People’s Republic of China College of Physics and Communication Electronics Jiangxi Normal University Nanchang 330022 People’s Republic of China School of Science Hubei University of Automotive Technology Shiyan 442002 China School of Electrical and Electronic Engineering Wuhan Polytechnic University Wuhan 430023 People’s Republic of China

We improve the test of the gravitational inverse-square law at the submillimeter range by suppressing the vibration of the electrostatic shielding membrane to reduce the disturbance coupled from the residual surface potential. The result shows that, at a 95% confidence level, the gravitational inverse-square law holds (|α|≤1) down to a length scale λ=48 μm. This work establishes the strongest bound on the magnitude α of the Yukawa violation in the range of 40–350 μm, and improves the previous bounds by up to a factor of 3 at the length scale λ≈70 μm. Furthermore, the constraints on the power-law potentials are improved by about a factor of 2 for k=4 and 5.

关键词： Experimental studies of gravity

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Advanced NOMA Assisted Semi-Grant-Free Transmission Schemes for Randomly Distributed Users

arXiv

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arXiv 2020年

作者： Lu, Huabing Xie, Xianzhong Shi, Zhaoyuan Lei, Hongjiang Yang, Helin Cai, Jun The Key Laboratory of Intelligent Control and Optimization for Industrial Equipment Ministry of Education Dalian University of Technology Dalian116024 China The School of Computer Science and Technology Chongqing University of Posts and Telecommunications Chongqing400065 China The Key Laboratory of Intelligent Perception and Computing of Anhui Province Anqing Normal University Anqing246011 China The School of Communication and Information Engineering Chongqing University of Posts and Telecommunications Chongqing400065 China The Department of Information and Communication Engineering School of Informatics Xiamen University Xiamen361005 China Department of Electrical and Computer Engineering Concordia University MontrealQCH3G 1M8 Canada

Non-orthogonal multiple access (NOMA) assisted semi-grant-free (SGF) transmission has recently received significant research attention due to its outstanding ability of serving grant-free (GF) users with grant-based (GB) users' spectrum, which greatly improves the spectrum efficiency and effectively relieves the massive access problem of 5G and beyond networks. In this paper, we first study the outage performance of the greedy best user scheduling SGF scheme (BU-SGF) by considering the impacts of Rayleigh fading, path loss, and random user locations. In order to tackle the admission fairness problem of the BU-SGF scheme, we propose a fair SGF scheme by applying cumulative distribution function (CDF)-based scheduling (CS-SGF), in which the GF user with the best channel relative to its own statistics will be admitted. Moreover, by employing the theories of order statistics and stochastic geometry, the outage performances of both BU-SGF and CS-SGF schemes are analyzed. Theoretical results show that both schemes can achieve full diversity orders only when the served users' data rate is capped, which severely limits the rate performance of SGF schemes. To further address this issue, we propose a distributed power control strategy to relax such data rate constraint, and derive analytical expressions of the two schemes' outage performances under this strategy. Finally, simulation results validate the fairness performance of the proposed CS-SGF scheme, the effectiveness of the power control strategy, and the accuracy of the theoretical analyses. Copyright © 2020, The Authors. All rights reserved.

关键词： Spectrum efficiency

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The Acquisition of Free Field Acoustic Characteristics of Targets in Water and Identification of Far-field Radiative Hot Zone

The Acquisition of Free Field Acoustic Characteristics of Ta...

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第二届船舶振动噪声国际研讨会

作者： LIN Wei LI Sheng LIU Chengpeng MENG Chunxia School of Naval Architecture ＆ Ocean Engineering Faculty of Vehicle Engineering and MechanicsDalian University of Technology Collaborative Innovation Center for Advanced Ship and Deep-sea Exploration Key Laboratory for Underwater Measurement and Control Technology

At present, sound wave is the most effective information carrier for long distance underwater propagation. It’s achievable to acquire target free field characteristics in a non-free field environment by sound field recovery technique based on boundary element method（BEM） in this paper. According to the calculation, the characteristics such as the sound pressure and sound power obtained in the recovered field and those in the free field are almost the same. At the same time, evanescent wave filtering technique is used to filter out the influence of evanescent wave and identification of far-field sound radiation hotspot in near field, which provides the basis for reduction vibration and noise. In this paper, an improved sound field separation technique combing sound field recovery technique based on BEM and supersonic sound intensity technique is proposed to get the free field characteristic of the target in a complex environment and identify the hot spot area radiating to the far field in near field, which is of great significance to target characteristic analysis and control.

关键词： Boundary element method free field recovery technique evanescent wave far field radiation hotspot

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Secure communications in a unified non-orthogonal multiple access framework

arXiv

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arXiv 2019年

作者： Yue, Xinwei Liu, Yuanwei Yao, Yuanyuan Li, Xuehua Liu, Rongke Nallanathan, Arumugam School of Information and Communication Engineering Key Laboratory of Modern Measurement & Control Technology Ministry of Education Beijing Information Science and Technology University Beijing100101 China School of Electronic Engineering and Computer Science Queen Mary University of London LondonE1 4NS United Kingdom School of Electronic and Information Engineering Beihang University Beijing100191 China

This paper investigates the impact of physical layer secrecy on the performance of a unified non-orthogonal multiple access (NOMA) framework, where both external and internal eavesdropping scenarios are examined. The spatial locations of legitimate users (LUs) and eavesdroppers are modeled by invoking stochastic geometry. To characterize the security performance, new exact and asymptotic expressions of secrecy outage probability (SOP) are derived for both code-domain NOMA (CD-NOMA) and power-domain NOMA (PD-NOMA), in which imperfect successive interference cancellation (ipSIC) and perfect SIC (pSIC) are taken into account. For the external eavesdropping scenario, the secrecy diversity orders by a pair of LUs (the n-th user and m-th user) for CD/PD-NOMA are obtained. Analytical results make known that the diversity orders of the n-th user with ipSIC/pSIC for CD-NOMA and PD-NOMA are equal to zero/ K and zero/one, respectively. The diversity orders of the m-th user are equal to K/one for CD/PD-NOMA. For the internal eavesdropping scenario, we examine the analysis of secrecy diversity order and observe that the m-th user to wiretap the n-th user with ipSIC/pSIC for CD-NOMA and PDNOMA provide the diversity orders of zero/K and zero/one, respectively, which is consistent with external eavesdropping scenario. Numerical results are present to confirm the accuracy of the analytical results developed and show that: i) The secrecy outage behavior of the n-th user is superior to that of the m-th user;ii) By increasing the number of subcarriers, CD-NOMA is capable of achieving a larger secrecy diversity gain compared to PD-NOMA. Copyright © 2019, The Authors. All rights reserved.

关键词： Geometry

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Robust Design of Transmit/Receive Beamforming for Multiple-input Multiple-output Radar

Robust Design of Transmit/Receive Beamforming for Multiple-i...

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2019 IEEE International Conference on Signal, Information and Data Processing, ICSIDP 2019

作者： Qian, Junhui Luo, Yu Fu, Ning Liu, Ran Feng, Zeyu School of Microelectronic and Communication Engineering Chongqing University Chongqing China Harbin Institute of Technology Department of Automatic Test and Control Harbin China College of Computer Science Chongqing University Chongqing China Chengdu Surveying Geotechnical Research Institute Co. Ltd. of MCC Chengdu China

ISBN: (纸本)9781728123455

The transmit/receive robust adaptive beamformer design of a multiple-input multiple-output (MIMO) radar system is studied in this paper. We first construct the interference covariance matrix via a shrink-based approach. Then, the desired transmit-receive steering vector (SV) is estimated through maximizing the output power upon the cooperative constraint and norm constraints under the presumed SV. An iterative procedure is designed to deal with the original nonconvex problem, whose convergence is analytically proven with the estimated SV. Simulation results show the merits of the proposed design in various scenarios. © 2019 IEEE.

关键词： MIMO radar

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Fuzzy control of dc microgrid

Fuzzy control of dc microgrid

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IEEE International Conference on Power, Intelligent Computing and Systems (ICPICS)

作者： Yinping An Xiangping Meng Hui Wang Qi Yao Chunhui Liang Changchun University of Technology College of Electrical and Electronic Engineering Changchun China National Local Joint Engineering Research Center for Intelligent Distribution Network Measurement and control with Safety Operation Technology School of Electrical Engineering and Information Technology Changchun China Changchun Institute of Technology School of Electrical Engineering and Information Technology Changchun China

ISBN: (纸本)9781728137216

Aiming at the problem of large overshoot and long response time of bidirectional DC/DC in the energy storage part of DC micro-grid, a fuzzy self-tuning PI controller is designed in this paper to realize online setting of control parameters and achieve the purpose of optimizing traditional PI control. The results show that fuzzy self-tuning PI control can effectively solve the problem of slow tracking voltage and fluctuation in dc micro-grid.

关键词： Voltage control Batteries Supercapacitors PI control Photovoltaic systems

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Optimization of Deep Convolution Neural Network Based on Sparse DropConnect 2

Optimization of Deep Convolution Neural Network Based on Spa...

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2018 2nd International Conference on Artificial Intelligence, Automation and control Technologies, AIACT 2018

作者： Liu, Mengxi Song, Jiuxu Wang, Zheng Ju, Yongfeng School of Electronic and Control Engineering Chang'An University Xi'an710064 China Shaanxi Key Laboratory of Measurement and Control Technology for Oil and Gas Wells Xi'an710065 China

According to the problem of overfitting in the traditional Convolutional Neural Networks(CNN) with large samples, an improved sparse DropConnect algorithm is put forward. With proposed algorithm, the CNN is improved and optimized. The performance of the network in image recognition is verified. Experiments of weld image recognition and classification indicate that the selective ability of the CNN on the sparse feature is improved. High recognition accuracy and classification accuracy of test sample are achieved. Over-fitting in the traditional network model can be avoided. More important, the feature sparsity and discriminative ability of the CNN are increased. © 2018 Published under licence by IOP Publishing Ltd.

关键词： Image recognition

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A General 3D Geometry-Based Stochastic Model for Industrial IoT Environments

A General 3D Geometry-Based Stochastic Model for Industrial ...

引用

IEEE Globecom Workshops

作者： Yang Liu Cheng-xiang Wang Rong Dai Xin Guo Yu Yu National Mobile Communications Research Laboratory School Information of Science and Engineering Southeast University Nanjing China State Key Laboratory of Millimeter Waves Southeast University Nanjing China Ministerial Key Laboratory of Advanced Control for Light Industry Processes Jiangnan University Wuxi China Purple Mountain Laboratories Nanjing China School of Information and Communication Engineering Nanjing Institute of Technology Nanjing China

ISBN: (数字)9781728173078

ISBN: (纸本)9781728173085

Industrial Internet of things (IoT) environment is one of the typical scenarios in the beyond fifth generation (B5G) networks. In this paper, a general three dimensional (3D) geometry-based stochastic model (GBSM) is proposed for the industrial IoT environments. Typical channel parameters, such as the power, delay, azimuth angle of arrival (AAOA), azimuth angle of departure (AAOD), elevation angle of arrival (EAOA), elevation angle of departure (EAOD) are combined to model the channel impulse response (CIR). The spatial consistency of the parameter is achieved by the sum of sinusoids (SOS) method. The spatial non-stationarity is modeled by describing the birth and death of the clusters under the industrial environments. To support the broadband channel, the CIR is modeled at each bin of the whole spectrum and the frequency correlation of the parameters is taken into account. Extensive simulated and measured results validate the credibility of the proposed model.

关键词： Solid modeling Three-dimensional displays Correlation Stochastic processes Delays Broadband communication Industrial Internet of Things

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A Stochastic Coupling-Based Channel Impulse Response Matrix Model for Massive MIMO Channels

A Stochastic Coupling-Based Channel Impulse Response Matrix ...

引用

International Conference on Wireless communications and Signal Processing (WCSP)

作者： Rong Dai Yang Liu Cheng-Xiang Wang Yu Yu Xin Guo Ministerial Key Laboratory of Advanced Control for Light Industry Processes Jiangnan University Wuxi China State Key Laboratory of Millimeter Waves Southeast University Nanjing China National Mobile Communications Research Laboratory School of Information of Science and Engineering Southeast University Nanjing China Purple Mountain Laboratories Nanjing China School of Information and Communication Engineering Nanjing Institute of Technology Nanjing China

ISBN: (数字)9781728172361

ISBN: (纸本)9781728172378

A novel stochastic channel impulse response matrix (CIRM) model for massive multiple input multiple output (MI-MO) channels is proposed in this papen Under the framework of this proposed model, the CIRM can be modeled as a sum of couplings between the steering vectors at the base station (BS) end and the eigenbases at the mobile station (MS) side. The fading of the coupling between the steering vector and the eigenbase is modeled as Nakagami distribution. Furthermore, the closed form of the capacity is derived based on the proposed framework. Compared with the traditional Weibchselberger model, the proposed model has lower complexity. To validate the proposed model, extensive massive MIMO channel measurements are carried out in an indoor environment The results show that the new model provides a better fit to the measured results than Weibchselberger model. Finally, the closed form and PDF are validated by Monte Carlo realizations of the proposed model. This CIRM model can be used for massive MIMO design in future fifth-generation communication system design.

关键词： Wireless communication Signal processing Conferences

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Time-Sensitive Networking as the communication Future of Industry 4.0

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IFAC-PapersOnLine 2019年第27期52卷 133-138页

作者： F. Zezulka P. Marcon Z. Bradac J. Arm T. Benesl Department of Control and Instrumentation Faculty of Electrical Engineering and Communication Brno University of Technology Technicka 3082/12 Brno 616 00 Czech Republic Department of Theoretical and Experimental Electrical Engineering Faculty of Electrical Engineering and Communication Brno University of Technology Technicka 3082/12 Brno 616 00 Czech Republic Department of Control and Instrumentation Faculty of Electrical Engineering and Communication Brno University of Technology Technicka 3082/12 Brno 616 00 Czech Republic and Department of Technical Studies School of Polytechnics Jihlava Tolsteho 16 Jihlava 586 01 Czech Republic

The paper discusses new trends within communication protocols of the Internet of Things (IoT), focusing especially on the enhancement of the IoT’s real-time abilities and summarizing the long-term knowledge and experience of the authors. Considering the previous standardization attempts of the ISO and IEEE, we may expect that the novel research projects will facilitate major progress in real-time communication systems to satisfy common requirements of industrial automation, information and audiovisual technologies, mechanical engineering, management, banking, medical care, and multiple other sectors covered by the Internet of Things (IoT). In this context, time-sensitive networks (TSNs) appear to embody a most effective approach to securing reliable communication for the future.

关键词： Internet of Things (IoT) Industrial Internet of Things (IIoT) Open Platform communication - Unified Architecture (OPC UA) Time-Sensitive Networks (TSN)

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