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

作者： Linglong Gou Jing Ma Bin Shi Zhongbo Zhu Lin Peng Key laboratory of Microwave and Optical Wave Application Technology Guilin University of Electronic Technology Guilin Guangxi China The Science and Technology on special system simulation laboratory Beijing Simulation Center Beijing China The National Key Laboratory of Science and Technology on Space Microwave Xi'an China

In this manuscript, a dual-polarized wideband wide beamwidth magneto-electric (ME) dipole antenna for millimeter-wave mobile communication is proposed. As can be seen from the simulation results, this design exhibits excellent performance. Owing to the mutual resonances of the magnetic dipole and the electric dipole, large bandwidths of 64.8% and 59% (18.4 GHz-33 GHz and 17.29 GHz-33.9 GHz) are obtained for the two polarizations, respectively. The isolation between the two ports is greater than 25 dB. By loading metal vias, the antenna's beamwidth is widened to more than 100° through the whole operating band. The antenna size is $\mathbf{5}\mathbf{mm}\times \mathbf{5}\mathbf{mm}\times \mathbf{1.72}\mathbf{mm}$ , and this compact structure is quite suitable for using in beam scanning antennas.

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A Compact Antenna Test Range Designed by All-Dielectric Transmitarray

A Compact Antenna Test Range Designed by All-Dielectric Tran...

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International Conference on Microwave and Millimeter Wave technology Proceedings

作者： Fan Liu Jing Ma Bin Shi Zhong-bo Zhu Lin Peng The Key Laboratory of Microwave and Optical Wave Application Technology Guilin University of Electronic Technology Guilin Guangxi China The Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing China The National Key Laboratory of Science and Technology on Space Microwave Xi'an China

ISBN: (数字)9798350389968

ISBN: (纸本)9798350389975

In this paper, an all-dielectric transmitarray compact antenna test range (TACATR) is proposed. The TACATR can be used as a low-cost alternative to traditional reflector compact antenna test range. The aperture perturbation mechanisms of the TACATR have been investigated, including aperture scattering interference and edge diffraction. Two optimization strategies are proposed to enhance the performance of the quiet zone (QZ). On the one hand, the unwanted edge diffraction is suppressed by employing suitable feeding sources and optimizing the focal aperture ratio (F/D). On the other hand, the interference of aperture scattering in QZ was further suppressed by optimizing the additional phase shift (APS). As an example, a Circular transmitarray (TA) with the dimension of 91mm was designed, which verifies the mechanism of interferences suppressing.

关键词： Microwave antennas Diffraction Horn antennas Perturbation methods Transmitting antennas Millimeter wave technology Scattering

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Ultra-wideband High Gain Circularly Polarized All Dielectric Lens Antenna

Ultra-wideband High Gain Circularly Polarized All Dielectric...

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International Conference on Microwave and Millimeter Wave technology Proceedings

作者： Chen Wang Jing Ma Bin Shi Zhong-bo Zhu Lin Peng The Key Laboratory of Microwave and Optical Wave Application Technology Guilin University of Electronic Technology Guilin Guangxi China The Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing China The National Key Laboratory of Science and Technology on Space Microwave Xi'an China

ISBN: (数字)9798350389968

ISBN: (纸本)9798350389975

In this paper, An ultra-wideband high gain circularly polarized all dielectric lens antenna is proposed. The lens antenna consists a linearly polarized horn and a dielectric lens with a gap. The impedance bandwidth, axial ratio and gain of the antenna can be improved by changing the shape of the lens. The PSO-GA is used to improve the design optimization efficiency of lens antenna, and the modeling time is shortened through the integrated modeling technology. The impedance bandwidth of the lens antenna is 40%, the maximum axial ratio is 2.8dB, and the maximum gain is 21.5dBic at 65GHz. In the 60-90GHz frequency band, the gain is greater than 20.5dBic.

关键词： Microwave antennas Polarization Shape Horn antennas simulation Bandwidth Ultra wideband antennas

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Broadband Polarization-Conversion Metasurface for a Cassegrain Antenna with High Polarization Purity

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Physical Review Applied 2019年第1期12卷 014009-014009页

作者： Wen-Long Guo Guang-Ming Wang Ke Chen Hai-Peng Li Ya-Qiang Zhuang He-Xiu Xu Yijun Feng Air and Missile Defense College Air Force Engineering University Xi’an 710051 China Department of Electronic Engineering School of Electronic Science and Engineering Nanjing University Nanjing 210093 China Science and Technology on Complex Aviation Systems Simulation Laboratory Beijing 100076 China

Polarization conversion has been widely explored in the study of metasurfaces in order to achieve broad operation bandwidths, but its application is still restricted to a few practical scenarios. We design a broadband cross-polarization conversion metasurface and apply it to form a directionally radiated Cassegrain antenna with a low profile and high polarization purity. A quasi-I-shaped meta-atom is first optimized with both high cross-polarization conversion efficiency and a full span of phase modulation in a broad bandwidth. With a hyperbolic phase profile imposed on the surface, a metasurface is engineered that can conduct both focusing and polarization conversion into its cross-polarization component. Then, by introducing a polarized grating as a subreflector and simultaneously fixing the designed metasurface as the main reflector, a planar Cassegrain antenna is facilitated with a low profile, high gain, and high polarization purity in a broad frequency band. This strategy of broad-band polarization conversion and its attempt to design a Cassegrain antenna lays a foundation for high-performance functional devices, promising great potential in real-world applications.

关键词： Metamaterials Polarization of light Radio frequency techniques Devices Wireless communication networks Electromagnetic wave theory Microwave techniques

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The view growth pattern of user generated videos on YouTube

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International Journal of u- and e- Service, science and technology 2016年第6期9卷 433-444页

作者： Zhou, Renjie Xia, Dongchen Yin, Yuyu Zhang, Jilin Zhang, Wei College of Computer Science and Technology Hangzhou Dianzi University Hangzhou China Key Laboratory Complex System Modeling and Simulation Ministry of Education Hangzhou China

With the rapid development of social media, video sharing sites like YouTube are getting more and more attention. Discovering the view growth pattern have become interesting topics for researchers as well as advertisers, media companies. In this paper, we analyze two aspects about video view growth pattern of YouTube videos. Firstly, the pattern of aggregated view is studied. It is found that the aggregated view rate peaks in the first few days, and falls quickly in the following days, and then decrease slowly during the consecutive weeks. Finally, the view rate tends to be a constant on the long run. The aggregated view count after a period of two months can be fitted with a linear line. Secondly, the view growth pattern of individual video is explored. The results indicate that the majority of videos peak at the very beginning of videos’ lifetime, and the category of view sources causes the peak is different. The view count of individual video and the view count from each source item also stabilize after a period of two months, and we finally show the referring time and active period of each source item. © 2016 SERSC.

关键词： Growth rate

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Design and evaluation of natural light guiding system in ecological illumination of traffic tunnel

Design and evaluation of natural light guiding system in eco...

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SPIE Optical Engineering + Applications

作者： Chen, Cheng-Nan Chen, Yi-Yung Whang, Allen Jong-Woei Chen, Li-Hsien Photonics System Simulation and Design Laboratory Department of Electro-Optical Engineering National Taiwan University of Science and Technology #43 Sec. 4 Keelung Rd. Taipei 106 Taiwan Photonics System Simulation and Design Laboratory Department of Electronic Engineering National Taiwan University of Science and Technology #43 Sec. 4 Keelung Rd. Taipei 106 Taiwan Department of Civil Engineering Graduate Institute of Civil and Disaster Prevention Engineering National Taipei University of Technology #1 Sec. 3 Jhongsiao E. Rd. Taipei 106 Taiwan

ISBN: (纸本)9780819477132

Ecological traffic tunnel means that the manner can deal with tunnel project environmental problem of surrounding area and it is most close to the green environment. In general, we always use artificial light sources, such as traditional light sources and LED, to be the light source of illumination in the traffic tunnel. However, the best light source for the health of the human body is the natural light. If we can guide the sunlight into the tunnel to be lighting source, it would have a great benefit to the health of the human body. In this paper, we use Natural Light Guiding system to provide ecological illumination in traffic tunnel. The system has collecting, transmitting, and lighting parts. In the collecting part, we utilize a static concentrator to collect sunlight which is made up of a prismatic and cascadable unit. In the transmitting part, the collected sunlight is guided by optical fiber or lightpipe efficiently. In the lighting part, we design a lighting module of road lamp for lighting the inside the tunnel. The lighting module redistributes light to conform the traffic regulation. Finally, we build a model of traffic tunnel in optical software with Natural Light Guiding system to simulate the performance. © 2009 Copyright SPIE - The International Society for Optical Engineering.

关键词： Light sources

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Erratum to: Depth estimation using an improved stereo network (Frontiers of Information technology & electronic Engineering, (2022), 23, 5, (777-789), 10.1631/FITEE.2000676)

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Frontiers of Information technology and electronic Engineering 2023年 1-1页

作者： Xu, Wanpeng Zou, Ling Wu, Lingda Qi, Yue Qian, Zhaoyong Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing101416 China Peng Cheng Laboratory Shenzhen518055 China Digital Media School Beijing Film Academy Beijing100088 China

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DeepDir: a deep learning approach for API directive detection

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science China(Information sciences) 2021年第9期64卷 238-240页

作者： Jingxuan ZHANG He JIANG Shuai LU Ge LI Xin CHEN College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics State Key Laboratory for Novel Software Technology Nanjing University Key Laboratory of Complex Systems Modeling and Simulation Ministry of Education School of Software Dalian University of Technology School of Electronic Engineering and Computer Science Peking University School of Computer Science and Technology Hangzhou Dianzi University

Dear editor,Software developers tend to reuse existing libraries to facilitate their development process and implement certain functionalities by invoking application programming interfaces(APIs) [1]. However, it remains a challenging task for developers to correctly use APIs [2], so they often consult API learning resources [3, 4]. As one of the most important API learning resources,

关键词： Information systems and Communication Service

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A DDS-based C-band wideband agile frequency synthesizer

A DDS-based C-band wideband agile frequency synthesizer

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International Workshop on Microwave and Millimeter Wave Circuits and system technology (MMWCST)

作者： Xin Xu Xiaohong Tang Tao Wu National Defense Key Laboratory of Extremely High Frequency Complex System University of Electronic Science and Technology of China Chengdu China

ISBN: (纸本)9781467355025

In this paper, a DDS-based C-band wideband agile frequency synthesizer is described. The DDS (Direct Digital Synthesizer) is used to achieve agile frequency hopping. The output of DDS is combined with four independent PLLs, which generate low phase noise LO signal, to expand the bandwidth. Measured results show that the frequency hopping time is shorter than 500ns. The spur suppression is better than 60dB and the phase noise is lower than -104dBc/Hz@10kHz from 6.84~7.956GHz.

关键词： Synthesizers Frequency synthesizers Phase noise Frequency measurement Wideband Clocks Semiconductor device measurement

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Agent Optimization Decision-Making Method Based on Self-Play

Agent Optimization Decision-Making Method Based on Self-Play

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IEEE International Conference on Unmanned systems (ICUS)

作者： Chunyi Duan Rongling Xiong Luyou Zhang Huaming Ran Qing Yang National Key Laboratory of Complex Aviation System Simulation China Electronics Technology Group Corporation Tenth Research Institute Chengdu China National Key Laboratory of Complex Aviation System Simulation China Electronic Technology Group Corporation Tenth Research Institute Chengdu China Unit 93216 People's Liberation Army of China Beijing China

ISBN: (数字)9798350384185

ISBN: (纸本)9798350384192

Aiming at the problem that the traditional deep reinforcement learning algorithm has poor generalization ability of generating strategies when solving complex game problems such as real-time strategy games, an agent strategy optimization method based on the combination of expert knowledge and self-play is proposed. Firstly, the opponent strategy of the agent is designed based on expert knowledge, and the corresponding strategy is generated by the proximal policy optimization algorithm (PPO), and the generated strategy is continuously put into the opponent strategy pool to provide a variety of opponent strategies for the agent in the training process. Through continuous iterative confrontation, the agent's autonomous decision-making ability in the face of different opponent strategies is improved. The simulation results show that compared with the traditional deep reinforcement learning algorithm, the introduction of the self-play training framework can significantly improve the average confrontation rate of the agent strategy, improve the robustness and generalization ability of the agent confrontation strategy, guide the agent to learn more effective tactical strategy, and achieve the adversarial advantage of “Priority first enemy discovery, Priority enemy launch”.

关键词： Training simulation Decision making Optimization methods Games Deep reinforcement learning Market research Robustness Real-time systems Iterative methods

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