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International Conference on Sensing technology, ICST

作者： Jishun Li Xiqiang Ma Xin Sui Fang Yang Zhiqiang Guan Hal Gurgenci Henan Key Laboratory for Machinery Design and Transmission System Henan University of Science and Technology Luoyang China The University of Queensland Brisbane Queensland Australia

ISBN: (数字)9781728148076

ISBN: (纸本)9781728148083

In order to address the problems such as heavy weight, high cost and poor sensitivity related to the swing frame of the existing roller test system, a micro-roller dynamic balance test system based on Micro-Electro-Mechanical systems (MEMS) acceleration sensor is proposed. The MEMS accelerometer is symmetrically embedded acting as the support of the swing frame to measure the vibration acceleration. The circuit board with perforated processing is directly used as the support of the swing frame. Two wires are used to connect the sensor and the data acquisition system to avoid the interference of cable elasticity on the vibration characteristics of the swing frame. The data obtained from this test system has been processed. The influence of various interference signals in the system on the vibration measurement is identified. Vibration signals generated by imbalances are extracted from complex measurement signals. The test data show that the optimized swing frame design has smaller weight, lower cost, higher sensitivity, simpler operation and much broad application range.

关键词： Vibrations Micromechanical devices Frequency measurement Vibration measurement Printed circuits Testing Accelerometers

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Precision Cylindricity Error Measurement system design and Error Analysis

Precision Cylindricity Error Measurement System Design and E...

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International Conference on Sensing technology, ICST

作者： Xiqiang Ma Fang Yang Jishun Li Zhiqiang Guan Hal Gurgenci Henan Key Laboratory for Machinery Design and Transmission System Henan University of Science and Technology Luoyang China The University of Queensland Brisbane Queensland Australia

ISBN: (数字)9781728148076

ISBN: (纸本)9781728148083

A precise cylindricity error measurement system is designed for cylindricity error measurement. Firstly, three-point cylindricity error separation algorithm and cylindricity evaluation method are introduced. By eliminating rotation error and random error, accurate roundness error, radius error of different sections and least square center coordinate of measured sections are calculated, which eliminates the influence of installation eccentricity on measurement results. Then, according to the three-point error measurement principle, a set of precise circle is designed. Cylindricity error measurement system, and the use of OpenGL graphics technology to reconstruct the shape of the cylinder and three-dimensional display. Finally, a number of groups of experiments were carried out on the cylinder standard parts, and the experimental results were analyzed. The results show that the system can realize cylindricity error measurement based on three-point method, which is consistent with the nominal accuracy of standard parts, and has certain application value.

关键词： Measurement uncertainty Shape Sensors Position measurement Coordinate measuring machines Shape measurement Wavelength measurement

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Formal Verification of 5G-EAP-TLS Authentication Protocol

Formal Verification of 5G-EAP-TLS Authentication Protocol

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IEEE International Conference on Data science in Cyberspace (DSC)

作者： Jingjing Zhang Qiang Wang Lin Yang Tao Feng Army Engineering University of PLA Nanjing China National Key Laboratory of Science and Technology on Information System Security Beijing China

In mobile communication networks, the security of users' data depends on the guarantees provided by the authentication protocols. For the next generation of mobile network (i.e., 5G network), the 5G-EAP-TLS protocol has been proposed for this purpose. However, it is still unknown whether this protocol provides the claimed security guarantees or not. To fill this gap, we provide in this work the first formal model of 5G-EAP-TLS protocol and conduct a thorough analysis based on Scyther model checker. Secondly, we identify several design flaws in the protocol, which may jeopardize the security goals and result in severe security vulnerabilities when implemented in real systems. To our knowledge, this is the first study on the formal verification of 5G-EAP-TLS protocol.

关键词： Protocols Authentication Home automation Analytical models Cryptography 5G mobile communication

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Approaching the Fundamental Limit of Orbital Angular Momentum Multiplexing Through a Hologram Metasurface

arXiv

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arXiv 2021年

作者： Yuan, Shuai S.A. Wu, Jie Chen, Menglin L.N. Lan, Zhihao Zhang, Liang Sun, Sheng Huang, Zhixiang Chen, Xiaoming Zheng, Shilie Jiang, Li Jun Zhang, Xianmin Sha, Wei E.I. College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China Ministry of Education The Key Laboratory of Electromagnetic Environmental Sensing Department of Education of Anhui Province Anhui University Hefei230039 China Department of Electrical and Electronic Engineering The University of Hong Kong Hong Kong Department of Electronic and Electrical Engineering University College London Torrington Place LondonWC1E 7JE United Kingdom Anhui Province Key Laboratory of Simulation and Design for Electronic Information System Hefei Normal University Hefei230601 China School of Electronic Science and Engineering University of Electronic Science and Technology of China Chengdu611731 China School of Information and Communications Engineering Xi’an Jiaotong University Xi’an710049 China

Establishing and approaching the fundamental limit of orbital angular momentum (OAM) multiplexing are necessary and increasingly urgent for current multiple-input multiple-output research. In this work, we elaborate the fundamental limit in terms of independent scattering channels (or the degrees of freedom of scattered fields) through angular-spectral analysis, in conjunction with a rigorous Green’s function method. The scattering-channel limit is universal for arbitrary spatial-mode multiplexing, which is launched by a planar electromagnetic device, such as antenna, metasurface, etc., with a predefined physical size. As a proof of concept, we demonstrate both theoretically and experimentally the limit by a phase-only metasurface hologram that transforms orthogonal OAM modes to plane-wave modes scattered at critically separated angular-spectral regions. Particularly, a minimax optimization algorithm is applied to suppress angular-spectrum aliasing, achieving good performances in both full-wave simulation and experimental measurement at microwave frequencies. This work offers a theoretical upper bound and corresponding approach route for engineering designs of OAM multiplexing. Copyright © 2021, The Authors. All rights reserved.

关键词： Spectrum analysis

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Numerical Comparison of Transpiration Cooling designs Using Real Gas Effects and Approximate Gas Model

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Journal of Physics: Conference Series 2021年第1期2097卷

作者： Meng Wang Jianhua Wang Fei He Kang Qian Yadong Wu Guangsheng Zhu CAS Key Laboratory of Mechanical Behaviour and Design of Materials Department of Thermal Science and Energy Engineering University of Science and Technology of China Hefei 230027 Anhui China Beijing Institute of Astronautical System Engineering Beijing 100076 China

In the severe high-temperature environment caused by aerodynamic heating, the vibrational excitation, dissociation and ionization of gas may successively occur, which are known as real gas effects. Under the real gas effects, the thermodynamic properties of gas vary drastically and significantly influence the performances of the active thermal protection system of hypersonic vehicles, especially in the case with coolant outflow, for example transpiration cooling. This paper numerically investigates the transpiration cooling performance with the consideration of the interaction between coolant outflow and hypersonic flow under the real gas effects. The mathematical models and coupled numerical strategy are firstly validated by experimental data, then the influences of real gas effects on the transpiration cooling of a wedged leading edge (WLE) are studied under a flight Mach number range from 8 to 12 and a flight height of 40 km. The analysis and discussions of the numerical results reveal some important phenomena and demonstrate the need to consider real gas effects.

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Optimizing design of multi-coil solenoid HTS magnet by PSO algorithm

Optimizing design of multi-coil solenoid HTS magnet by PSO a...

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2018 IEEE International Conference on Applied Superconductivity and Electromagnetic Devices, ASEMD 2018

作者： Huang, Wen Chen, Jun Quan National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan China

ISBN: (纸本)9781538624944

The superconducting magnet has been used more and more widely due to the advances in refrigeration technology and superconducting material. Consequently, its design requirements become higher. This paper combines particle swarm optimization (PSO) and numerical calculation using finite-element (FE) for the rapidly-optimized design of multi-coil solenoid high-temperature-superconducting (HTS) magnet which must satisfy the need of electromagnetism. On this basis, the length of the material used will be minimized. With the optimum design of a magnetic fluid propeller as an example, the second-generation HTS material is selected for developing a superconducting magnet prototype, which is not lower than 6T in central magnetic field strength, not less than 340∗100mm2 in its uniform region and not less than 100mm in diameter. © 2018 IEEE.

关键词： Superconducting magnets

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Feasibility analysis of helical superconducting MHD propulsor for vessel propulsion

Feasibility analysis of helical superconducting MHD propulso...

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2018 IEEE International Conference on Applied Superconductivity and Electromagnetic Devices, ASEMD 2018

作者： Chen, Junquan Wang, Dong Huang, Wen Jin, Shuangbao Zhu, Hao National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan China

ISBN: (纸本)9781538624944

In this paper, a MHD propulsor model for design and optimization is built. And it is used to achieve the most efficient propulsor with the given warm bore diameter and field strength, then these two constraint parameters are scanned within the range of 0.11 m, 120 Tesla. Based on the result above and current status of magnet technology, we can infer that it is very difficult for MHD propulsor to be used practically. © 2018 IEEE.

关键词： Superconducting magnets

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Uncertainty analysis for input parameters of electrical cabinet fire simulation by coupling Latin hypercube sampling and CFAST 14

Uncertainty analysis for input parameters of electrical cabi...

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14th Probabilistic Safety Assessment and Management, PSAM 2018

作者： Wang, Wanhong Zhu, Dahuan Bao, Hui Guo, Yun Peng, Changhong School of Nuclear Science and Technology University of Science and Technology of China Hefei Anhui China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Chengdu Sichuan China Institute of Plasma Physics Chinese Academy of Sciences Hefei Auhui China

It has been proved that fire accident frequency in nuclear power plants is higher than we thought it was and fire accidents have a huge significant impact on the safety of nuclear power, so it is extremely necessary to analyze fire risks. Electrical cabinets are one of the most important fire ignition sources in nuclear power plants, since there are normally many combustible cable bundles inside them. When fire modeling has been performed in nuclear power plants, past studies have only considered a single fire scenario, which means that the uncertainties associated with fire combustion and propagation are ignored. The paper is based on electrical cabinet fire scenario simulations in nuclear power plants and analyze the uncertainty of input parameters related to fire combustion and fire detection by coupling Latin Hypercube Sampling and software-CFAST. Statistic results can be used for quantitative analysis in Fire Probabilistic Safety Assessment. © 2018 International Association for Probablistic Safety Assessment and Management (IAPSAM). All rights reserved.

关键词： Uncertainty analysis

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design of Multi-Beam Antenna Based on Rotman Lens

Design of Multi-Beam Antenna Based on Rotman Lens

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Wei-Jun Wu Zhi-Ya Zhang Ya-Rui Zhao Qi-Feng Liu Chun Wang Yu Zuo Science and Technology on Electromagnetic Compatibility Laboratory China Ship Development and Design Center Wuhan China National Key Laboratory of Antennas and Microwave Technology Xidian University Xi'an Shaanxi China

ISBN: (数字)9780996007894

ISBN: (纸本)9781728146331

A multi-beam antenna fed by Rotman lens is presented in this paper. The antenna system is composed of a Rotman lens and a 8×8 printed dipole antenna array. By properly comparing optical aberrations, expressing as the normalized path length errors, the suitable ratio of on-axis to off-axis focal length (g=G/F) is acquired so as to minimize phase errors for the array elements. Ten dummy ports are used to reduce the deterioration of performance due to energy reflection. A sample antenna was simulated, covering a wide scanning angle of±40°. The simulated beam patterns show that the eleven beam gains are distributed from 17.8 to 19.9 dBi under operating of 3.15 GHz, and similar results are obtained over 20% of the relative bandwidth. The great simulated results are used to verify the design approach.

关键词： Lenses Dipole antennas Microstrip antenna arrays Radar antennas Phased arrays

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design of Multi-Beam Antenna Based on Rotman Lens

Design of Multi-Beam Antenna Based on Rotman Lens

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International Conference on Microwave and Millimeter Wave technology Proceedings

作者： Junwen Zhang Weijun Wu Yang Feng Zhi-Ya Zhang National Key Laboratory of Antennas and Microwave Technology Xidian University Xi'an Shaanxi China Science and Technology on Electromagnetic Compatibility Laboratory China Ship Development and Design Center Wuhan China

A multi-beam antenna fed by Rotman lens is presented in this paper. A Rotman lens and a ten-element printed Yagi antenna array make up the antenna system. By properly comparing optical aberrations, expressing as the normalized path length errors, the suitable ratio of on-axis to off-axis focal length (g = G/F) is acquired so as to minimize phase errors for the array elements. Ten dummy ports are used to reduce the deterioration of performance due to energy reflection. A sample antenna was fabricated and measured, covering a wide scanning angle of ±30°. The measured beam patterns show that the seven beam gains are distributed from 11.9 to 13.6 dBi under operating of 8.15 GHz. Both the simulated and measured results are used to verify the design approach.

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