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IEEE International Conference on Electronic Information and Communication technology (ICEICT)

作者： Yuwei Qiu Zhiye Jiang Pei Zheng School of Electronic Information Northwestern Polytechnical University Xi'an China National Key Laboratory of Science and Technology on Test Physics & Numerical Mathematics Beijing China

ISBN: (数字)9781728190457

ISBN: (纸本)9781728190464

Design of non-uniform flexible meta-surface for antenna beam-steering is presented in this paper. By properly tuning the dimensions of quasi-I-shaped unit cells on meta-surface, we propose a bi-layer meta-surface that can achieve beam deflection of up to 34°. Horn antenna is adopted as the feed antenna to illuminate the meta-surface which is printed on flexible plastic sheet. The meta-surface is fixed on the outside surface of horn antenna with an electric motor, making it possible to slide relative to the aperture of feed antenna. The horn antenna together with the meta-surface will work like a projector when operating, the main-beam of the horn antenna can be steered when different frames of the meta-surface cover the horn aperture and the steering range is ±34°. Radiation reconfigurable is thus achieved through a simple structure. Prototype will be fabricated in the following research.

关键词： Horn antennas Prototypes Antenna feeds Aperture antennas Information and communication technology Plastics Tuning

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A Physical Layer key Generation method with Reliable Negotiation

A Physical Layer Key Generation method with Reliable Negotia...

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Signal, Information and Data Processing (ICSIDP), IEEE International Conference on

作者： Yuchen Wang Xuanli Wu Zhicong Xu Wei Wu Hu Li Ran Zhang School of Electronics and Information Engineering Harbin Institude of Technology Harbin China National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing China

ISBN: (数字)9781728123455

ISBN: (纸本)9781728123462

There is a risk of information leakage in the process of wireless communication. The introduction of key generation in the physical layer can effectively improve the security of wireless communication. This paper proposes a new physical layer key generation method in the TDD (time division duplex) communication system. Assume that the uplink and downlink channels are reciprocal. Through LDPC (Low Density Parity Check)channel coding and negotiation algorithm, the inconsistency rate of key generation between Alice and Bob is reduced. Simulation and analysis results show that the method improves the key generation rate and reduces the key inconsistency rate.

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Piecewise Linear Recursive Convolution Method Applied in One-dimensional Unmagnetized Plasma

Piecewise Linear Recursive Convolution Method Applied in One...

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Jiaqi Liu Gang Meng Lei Mu Lu Gao Jinjun Mo Runhui Wu Weidong Wang National Key Laboratory of Science and Technology on Test Physics & Numerical Mathematics Beijing China School of Information and Communication Guilin University of Electronic Technology Guilin China

The piecewise linear recursive convolution(PLRC) method based on finite difference time domain(FDTD) is used to calculate the reflection and transmission characteristics of electromagnetic waves from one-dimensional unmagnetized plasma. The results are shown that this method has obvious advantages in accurately calculating the electromagnetic problems of one-dimensional, small-scale and thin-layer dielectric materials.

关键词： Convolution Electromagnetic scattering Dielectric materials Computational electromagnetics Reflection Plasmas Electromagnetics

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A Radiation Pattern-Reconfigurable Patch Antenna with Tunable CSRR based on Liquid Metal and 3-D Printed Microfluidics

A Radiation Pattern-Reconfigurable Patch Antenna with Tunabl...

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Yumeng Wang Lu Gao Pei Zheng Lingnan Song School of Electronic and Information Engineering Beihang University Beijing China National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing China

In this article, a radiation patternreconfigurable patch antenna with tunable complementary split-ring resonators (CSRR) based on liquid metal (LM) and 3-D printed microfluidics is presented. The antenna is composed of three layers, a top coaxial fed rectangular patch, a middle ground plane with two CSRRs etched symmetrically, and two bottom microfluidics channels each adhered underneath the corresponding CSRR. Pattern reconfiguration is achieved by filling the microfluidic channels with the liquid metal plugs to change the physical parameters of the CSRR structure. By adjusting the length of the slot stubs in CSRRs, the main beam of the double CSRR-loaded antenna can be continuously scanned from -46° to 46° in elevation plane.

关键词： Liquids Slot antennas Patch antennas Simulation Metals Filling Resonators

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Linkage Between Mei-yu Precipitation and North Atlantic SST on the Decadal Timescale

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Advances in Atmospheric sciences 2009年第1期26卷 101-108页

作者：顾薇李崇银王鑫周文李维京 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029 National Climate Center China Meteorological Administration Beijing 100081 Meteorological College PLA University of Science and Technology Nanjing 211101 City U-IAP Laboratory for Atmospheric SciencesDepartment of Physics & Materials Science City University of Hong Kong Hong Kong

This paper investigates the relationship between mei-yu and North Atlantic sea surface temperature anomalies （SSTA）. Results show that they are significantly associated with each other on the decadal timescale. Both mei-yu precipitation and mei-yu duration are characterized by significant decadal variability. Their decadal components are closely correlated with a triple mode of North Atlantic SSTA in the preceding winter. Regression analysis demonstrates that the wintertime North Atlantic SSTA may impose a delayed impact on East Asia Summer Monsoon （EASM） circulation and mei-yu on the decadal timescale. The persistency of SSTA plays an important role during this course. The triple SSTA mode can persist from winter until late spring. It is suggested that the springtime SSTA may excite a stationary wave-train propagating from west Eurasia to East Asia and exert an impact on mei-yu.

关键词： mei-yu decadal North Atlantic SSTA

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The S-PLUS Ultra-Short Survey: Photometric Re-calibration with the BEst STar Database

arXiv

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arXiv 2025年

作者： Li, Xiaolu Xiao, Kai Huang, Yang Yuan, Haibo Tang, Yanke Beers, Timothy C. Huang, Bowen Ma, Mingyang Humire, Pedro K. Alvarez-Candal, Alvaro Sestito, Federico Gai, Ning Mao, Yongna Gu, Hongrui Tao, Zhenzhao Yang, Lin Xu, Shuai Hu, Rong College of Physics and Electronic information Dezhou University Dezhou253023 China International Centre of Supernovae Yunnan Key Laboratory Kunming650216 China School of Astronomy and Space Science University of Chinese Academy of Sciences Beijing100049 China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Beijing102206 China CAS Key Lab of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing100012 China School of Physics and Astronomy Beijing Normal University No.19 Xinjiekouwai St Haidian District Beijing100875 China University of Notre Dame Notre DameIN46556 United States Departamento de Astronomia Instituto de Astronomia Geofísica e Ciências Atmosféricas da USP Cidade Universitária SP São Paulo05508-900 Brazil Instituto de Astrofísica de Andalucía CSIC Apt 3004 Granada18080 Spain Centre for Astrophysics Research Department of Physics Astronomy and Mathematics University of Hertfordshire HatfieldAL10 9AB United Kingdom College of Computer and Information Dezhou University Dezhou253023 China Institute for Astronomical Science Dezhou University Dezhou253023 China Department of Cyber Security Beijing Electronic Science and Technology Institute Beijing100070 China Department of Physics Beijing Technology and Business University Beijing100048 China

We present an independent validation and comprehensive re-calibration of S-PLUS Ultra-Short Survey (USS) DR1 12-band photometry using about 30,000–70,000 standard stars from the BEst STar (BEST) database. We identify spatial variation of zero-point offsets, up to 30–40 mmag for blue filters (u, J0378, J0395) and 10 mmag for others, predominantly due to the higher uncertainties of the technique employed in the original USS calibration. Moreover, we detect large- and medium-scale CCD position-dependent systematic errors, up to 50 mmag, primarily caused by different aperture and flat-field corrections. We then re-calibrate the USS DR1 photometry by correcting the systematic shifts for each tile using second-order two-dimensional polynomial fitting combined with a numerical stellar flat-field correction method. The re-calibrated results from the XPSP and the SCR standards are consistent within 6 mmag in the USS zero-points, demonstrating both the typical precision of re-calibrated USS photometry and a sixfold improvement in USS zero-point precision. Further validation using SDSS and Pan-STARRS1, as well as LAMOST DR10 and Gaia photometry, also confirms this precision for the re-calibrated USS photometry. Our results clearly demonstrate the capability and the efficiency of the BEST database in improving calibration precision to the milli-magnitude level for wide-field photometric surveys. The re-calibrated USS DR1 photometry is publicly available (doi: 10.12149/101503). Copyright © 2025, The Authors. All rights reserved.

关键词： Systematic errors

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Full-Space Beam Scanning Antenna Based on Spoof Surface Plasmon Polaritons

Full-Space Beam Scanning Antenna Based on Spoof Surface Plas...

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Zhicheng Wu Xianglin Kong Jun Wang Ruofeng Xu Lei Zhao Yinfang Xu School of Information and Control Engineering China University of Mining and Technology Xuzhou China National Key Laboratory of Science and Technology on Test Physics & Numerical Mathematics Beijing China

In this paper, a full-space beam scanning antenna based on spoof surface plasmon polaritons (SSPPs) is proposed. The proposed antenna is composed of a SSPPs loaded by the varactor diodes and periodic metallic patches. The periodic patches can transform the slow waves from SSPPs into fast waves, and the cutoff frequency can be reconfigured by changing the capacitance of the varactor diode, which will make the radiation angle of the beam change within a fixed frequency. Simulation results show that the radiation angle ranges from −90° to 90° at 9 GHz.

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Application of improved genetic ant colony optimization in radar resource interference allocation

Application of improved genetic ant colony optimization in r...

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IET International Radar Conference (IET IRC 2020)

作者： Y. Liao W. Guo L. Hu Harbin Engineering University Information and Communication Engineering Department Harbin China National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing China

Under the condition of limited interference resources, how to maximize the benefits of multiple jammers interfering with multiple radars has become a research hotspot. This paper has designed a reasonable interference evaluation method. Aiming at the disadvantages of genetic algorithm and ant colony optimization, made some improvements, and combined genetic methods and ant colony optimization, besides, a new crossover and mutation method based on constraints is proposed, which overcomes the shortcomings of invalid iteration of genetic algorithm and easy to fall into local optimal solution of ant colony optimization. Through simulation analysis, the fused algorithm can reach the optimal value within a short number of iterations, improving the utilization efficiency of the jammer.

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Coupling of the Calculated Freezing and Thawing Front Parameterization in the Earth System Model CAS-ESM

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Advances in Atmospheric sciences 2023年第9期40卷 1671-1688页

作者： Ruichao LI Jinbo XIE Zhenghui XIE Binghao JIA Junqiang GAO Peihua QIN Longhuan WANG Si CHEN State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 101408China School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China

The soil freezing and thawing process affects soil physical properties,such as heat conductivity,heat capacity,and hydraulic conductivity in frozen ground regions,and further affects the processes of soil energy,hydrology,and carbon and nitrogen *** this study,the calculation of freezing and thawing front parameterization was implemented into the earth system model of the Chinese Academy of sciences(CAS-ESM)and its land component,the Common Land Model(CoLM),to investigate the dynamic change of freezing and thawing fronts and their *** results showed that the developed models could reproduce the soil freezing and thawing process and the dynamic change of freezing and thawing *** regionally averaged value of active layer thickness in the permafrost regions was 1.92 m,and the regionally averaged trend value was 0.35 cm yr–*** regionally averaged value of maximum freezing depth in the seasonally frozen ground regions was 2.15 m,and the regionally averaged trend value was–0.48 cm yr–*** active layer thickness increased while the maximum freezing depth decreased year by *** results contribute to a better understanding of the freezing and thawing cycle process.

关键词： frozen ground freezing and thawing fronts maximum freezing depth active layer thickness earth system model CAS-ESM

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Source-Configured Microwave Plasmonic Vortices Based on Single Meta-Particle

Source-Configured Microwave Plasmonic Vortices Based on Sing...

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International Applied Computational Electromagnetics Society Symposium (ACES)

作者： Xianglin Kong Lei Zhao Xiaopeng Shen Yinfang Xu School of Information and Control Engineering School of Materials Science and Physics China University Mining and Technology Xuzhou China National Key Laboratory of Science and Technology on Test Physics & Numerical Mathematics Beijing China

In this paper, generation of plasmonic vortices with tunable topologic charges is proposed in the microwave regime. Tunable vortices with topologic charges of 0, +1 and -1 can be configured by illuminating incident plane waves with linearly polarization (LP), left-circularly polarization (LHCP) and right-circularly polarization (RHCP) on a single meta-particle, respectively. A spiral meta-particle operating at 2.94 GHz is designed, fabricated and measured to demonstrate the source-configured characteristics. The results showed that simulation and test are consistent with the theoretical ones.

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