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Potential key technologies for 6G mobile communications

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Science China(Information Sciences) 2020年第8期63卷 217-235页

作者： Yifei YUAN yajun zhao Baiqing ZONG Sergio PAROLARI China Mobile ZTE Corporation

The standard development of 5G wireless communication culminated between 2017 and 2019,followed by the worldwide deployment of 5G networks, which is expected to result in very high data rate for enhanced mobile broadband, support ultrareliable and low-latency services and accommodate massive number of connections. Research attention is shifting to future generation of wireless communications, for instance, beyond 5G or 6G. Unlike previous studies, which discussed the use cases, deployment scenarios,or new network architectures of 6G in depth, this paper focuses on a few potential technologies for 6G wireless communications, all of which represent certain fundamental breakthrough at the physical layer —technical hardcore of any new generation of wireless communications. Some of them, such as holographic radio, terahertz communication, large intelligent surface, and orbital angular momentum, are of revolutionary nature and many related studies are still at their scientific exploration stage. Several technical areas, such as advanced channel coding/modulation, visible light communication, and advanced duplex, while having been studied, may find more opportunities in 6 G.

关键词： 6G holographic radio terahertz large intelligent surface orbital angular momentum advanced channel coding modulation visible light communication

∼2.5 nm pores in carbon-based cathode promise better zinc-iodine batteries

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Chinese Chemical Letters 2024年第5期35卷 471-476页

作者： yajun Hou Chuanzheng Zhu Qiang Wang Xiaomeng zhao Kun Luo Zongshuai Gong Zhihao Yuan School of Materials Science and Engineering Tianjin Key Laboratory of Photoelectric Materials&DevicesTianjin University of TechnologyTianjin 300384China

The relationship mechanism between the material pore structures and cathodic iodine chemistry plays a vital role in efficient Zn-I_(2) batteries,but is unclear,retarding further *** work innovatively indicates a great contribution of∼2.5nm pore structure of nanocarbons to efficient iodine adsorption,rapid I^(−)↔I_(2) conversion,and polyiodide inhibition,via scrupulously designing catalysts with controllable pore sizes *** I_(2)-loading within the designed nitrogen-doped nanocarbons can reach up to as high as 60.8 wt%.The batteries based on the cathode deliver impressive performances with a large capacity of 178.8 mAh/g and long-term cycling stability more than 4000 h at 5.0 ***,these is no polyiodide such as I_(3)−and I_(5)−detected during the charge-discharge processes from comprehensive electrochemical cyclic voltammetry,X-ray photoelectron spectroscopy,and Raman *** work provides a novel knowledge-guided concept for rational pore design,promising better Zn-I_(2) batteries,which is also hoped to benefit other advanced energy technologies,such as Li-S,Li-ion,and Al-I_(2) batteries.

关键词： Zinc-iodine batteries Structure-performance relationship Iodine conversion chemistry Cathode materials Porous carbon

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面向空管模拟机培训的智能应答机长研究

海军航空大学学报 2024年第1期39卷 115-122页

作者：郭成龙廖伟田晨林毅吴九州赵雅珺游学杭李锦恒中国民用航空西南地区空中交通管理局四川成都610065 四川大学计算机学院四川成都610065

针对当前日益增长的空中交通管制员(以下简称“管制员”)培训需求以及传统管制员培训模拟机面临的效率低等问题,设计了1个面向空管模拟机培训的智能应答机长系统。该系统利用语音识别、指令提取、指令复诵、语音合成等技术,能够实现对... 详细信息

针对当前日益增长的空中交通管制员(以下简称“管制员”)培训需求以及传统管制员培训模拟机面临的效率低等问题,设计了1个面向空管模拟机培训的智能应答机长系统。该系统利用语音识别、指令提取、指令复诵、语音合成等技术,能够实现对管制模拟培训过程中管制员语音的智能识别和理解,并模拟飞行员自动输出复诵指令的功能。通过对真实空管对话语音模式的研究和分析,制定了1套详细的复诵规则,以适应不同场景下的管制指令复诵模式。此外,集成了特情处理模块以支持管制员特情处理培训。在真实管制培训环境下进行实验验证,结果表明,所提出的智能应答机长系统综合复诵准确率为88.6%,可以有效提升管制员培训质量和效率,显著降低了人力成本。并且,该系统可以作为子系统集成到现有的管制员培训模拟机系统中,具有较强的便捷性和兼容性。

关键词：空管模拟机智能机长指令复诵语音识别

AIRIS:Artificial Intelligence Enhanced Signal Processing in Reconfigurable Intelligent Surface Communications

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China Communications 2021年第7期18卷 158-171页

作者： Shun Zhang Muye Li Mengnan Jian yajun zhao Feifei Gao State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China Algorithm Department of Wireless Product R&D Institute ZTE CorporationBeijing 100029China Institute for Artificial Intelligence Tsinghua University(THUAI)State Key Lab of Intelligent Technologies and SystemsTsinghua UniversityBeijing National Research Center for Information Science and Technology(BNRist)Department of AutomationTsinghua University Beijing100084China

Reconfigurable intelligent surface(RIS)is an emerging meta-surface that can provide additional communications links through reflecting the signals,and has been recognized as a strong candidate of 6G mobile communications ***,it has been recently admitted that implementing artificial intelligence(AI)into RIS communications will extensively benefit the reconfiguration capacity and enhance the robustness to complicated transmission *** the conventional model-driven approaches,AI can also deal with the existing signal processing problems in a data-driven manner via digging the inherent characteristic from the real ***,AI is particularly suitable for the signal processing problems over RIS networks under unideal scenarios like modeling mismatching,insufficient resource,hardware impairment,as well as dynamical *** one of the earliest survey papers,we will introduce the merging of AI and RIS,called AIRIS,over various signal processing topics,including environmental sensing,channel acquisition,beamforming design,and resource scheduling,*** will also discuss the challenges of AIRIS and present some interesting future directions.

关键词： reconfigurable intelligent surface artifi-cial intelligence deep learning deep reinforcement learning signal processing

High-static-low-dynamic stiffness isolator based on an electromagnetic negative stiffness spring with long linear stroke

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Science China(Technological Sciences) 2024年第3期67卷 740-752页

作者： YUAN ShuJin WU yajun SONG DaiPing PU HuaYan MOU LiSheng HOU Lei zhao JingLei LI XuePing LUO Jun WU Jie HUANG XiaoXu State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China China Aerodynamics Research and Development Center Mianyang 621000China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

Negative stiffness mechanisms can improve low-frequency vibration isolation performance and have been widely used in the vibration isolation of precision equipment. However, the negative stiffness mechanism usually introduces a nonlinear stiffness,resulting in a nonlinear response and worsening the vibration isolation performance, especially under large amplitude *** this paper, an electromagnetic spring with linear negative stiffness(ESLNS) is proposed, in which the antagonistic ampere forces of the energized coils are used to generate negative stiffness within a long linear stroke. The magnetic field distribution is improved through the design of the magnetic circuit, thereby increasing the stiffness generation efficiency. The stiffness can be adjusted bidirectionally by current within the range of positive and negative stiffness. An electromagnetic stiffness model was established based on the equivalent magnetic circuit method. Experimental measurements verified the accuracy of the model and proved the linearity of the electromagnetic spring. A vibration isolator with high static and low dynamic stiffness(HSLDS) based on the ESLNS is designed and tested. The experimental results prove that the introduction of the ESLNS can effectively expand the isolation frequency band without changing the equilibrium position. Moreover, the vibration isolator with ESLNS does not produce nonlinear response. The proposed electromagnetic spring with linear negative stiffness extends the application range of HSLDS isolators to a large amplitude vibration environment.

关键词： linear negative stiffness mechanism low-frequency vibration isolation electromagnetic spring vibration control

Camellia sinensis CsMYB4a participates in regulation of stamen growth by interaction with auxin signaling transduction repressor CsAUX/IAA4

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The Crop Journal 2024年第1期12卷 188-201页

作者： Guoliang Ma Mingzhuo Li Yingling Wu Changjuan Jiang Yifan Chen Dawei Xing Yue zhao yajun Liu Xiaolan Jiang Tao Xia Liping Gao School of Life Science Anhui Agricultural UniversityHefei 230036AnhuiChina Plant for Human Health Institute Department of Plant and Microbial BiologyNorth Carolina State UniversityKannapolisNC 28081USA State Key Laboratory of Tea Plant Biology and Utilization/Key Laboratory of Tea Biology and Tea Processing of Ministry of Agriculture/Anhui Provincial Laboratory of Tea Plant Biology and Utilization Anhui Agricultural UniversityHefei 230036AnhuiChina

Subgroup 4(Sg4)members of the R2R3-MYB are generally known as negative regulators of the phenylpropanoid pathway in *** previous research showed that a R2R3-MYB Sg4 member from Camellia sinensis(CsMYB4a)inhibits expression of some genes in the phenylpropanoid pathway,but its physiological function in the tea plant remained ***,CsMYB4a was found to be highly expressed in anther and filaments,and participated in regulating filament *** analysis and exogenous auxin treatment showed that the target of CsMYB4a might be the auxin signal ***/indole-3-acetic acid 4(AUX/IAA4),a repressor in auxin signal transduction,was detected from a yeast two-hybrid screen using CsMYB4a as *** silencing assays showed that both CsIAA4 and CsMYB4a regulate filament *** plants overexpressing CsIAA4 were insensitive to exogenous a-NAA,consistent with overexpression of ***-protein interaction experiments revealed that CsMYB4a interacts with N-terminal of CsIAA4 to prevent CsIAA4 *** out of the endogenous NtIAA4 gene,a CsIAA4 homolog,in tobacco alleviated filament growth inhibition and a-NAA insensitivity in plants overexpressing *** results strongly suggest that CsMYB4a works synergistically with CsIAA4 and participates in regulation of the auxin pathway in stamen.

关键词： AUX/IAA4 Auxin signaling CsMYB4a Subgroup 4 R2R3-MYB

Iridic oxide nanoparticles grown in situ on BCN nanotubes as highly efficient dual electrocatalyst for rechargeable lithium-O2 batteries

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Journal of Energy Chemistry 2020年第10期29卷 291-298页

作者： Xufang Li yajun zhao Jing Zhang Chaoxiong Li Shan Wu Qiufan Shi Dawei Zhang Qingchun Yang School of Chemistry and Chemical Engineering Hefei University of TechnologyHefei 230009AnhuiChina Anhui Province Key Laboratory of Power Battery Tianneng Battery Group(Anhui Company)Jieshou 236500AnhuiChina School of Materials Science and Technology Hefei University of TechnologyHefei 230009AnhuiChina

Oxygen cathode catalysts can significantly address the issues faced by Li-O2 *** this research,a composite of IrO2 nanoparticles grown in situ on BCN nanotubes(IrO2@BCNNTs)has been synthesized by facile hydrothermal method,which is initially fabricated as cathode catalyst for Li-O2 *** results indicate that IrO2@BCNNTs nanocomposite has a better effect on improving the actual discharge capacity,voltage gap and cyclability of Li-O2 *** addition,it is also demonstrated that the Ir O2@BCNNTs composite exhibits bifunctional characteristics for both the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)through rotating disk electrode(RDE)*** excellent performances of the synthesized catalyst may be attributed to the unique interconnected tubular structure and strong synergistic effect,which can provide more charged sites and defect sites and then facilitate reversible Li2 O2 formation and ***,it is promising for applying the rational design of the bifunctional catalyst to Li-O2 battery.

关键词： BCN nanotubes IrO2@BCNNTs composite Rechargeable Li-O2 batteries

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《王子爱》婚纱店室内设计作品

家具与室内装饰 2023年第1期30卷 96-97页

作者：赵娅珺河南科技学院艺术学院河南新乡450303

该项目位于河南新乡核心商业区,是一家运用极简主义风格设计的婚纱店,我们希望它是一家体验感极佳、流畅和自由的婚纱店。在设计动线的过程,使顾客在其中可以保持相对松弛的状态。

关键词：婚纱店河南新乡极简主义风格核心商业区体验感室内设计作品

Perovskite oxides La_(0.4)Sr_(0.6)Co_xMn_(1-x)O_3(x=0,0.2,0.4) as an effective electrocatalyst for lithium-air batteries

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Green Energy & Environment 2018年第1期3卷 78-85页

作者： yajun zhao Tao Liu Qiufan Shi Qingchun Yang Chunxiao Li Dawei Zhang Chaofeng Zhang School of Chemistry and Chemical Engineering Hefei University of Technology

Co-doped perovskite oxide La_(0.4)Sr_(0.6)Co_xMn_(1-x)O_3(x=0, 0.2, 0.4) composites are prepared by sol-gel method utilizing citric acid as chelating agent. These composites show good catalytic activities when tested as catalysts rechargeable lithium-air batteries. In particular, the La_(0.4)Sr_(0.6)Co_(0.4)Mn_(0.6)O_3 shows a lower potential gap. When these samples are tested as catalysts for Li-air batteries at a current density of100 mA g^(-1), the discharge capacities with different La_(0.4)Sr_(0.6)Co_xMn_(1-x)O_3(x=0,0.2, 0.4) catalysts are 5819, 6420, and 7227 mA h g^(-1),respectively. In addition, under a capacity limitation of 1000 mA h g^(-1), the cell using La_(0.4)Sr_(0.6)Co_(0.4)Mn_(0.6)O_3 as catalyst shows good cycling stability up to 46 cycles. The good electrochemical performance suggests that suitable doping of Co in Mn site of La_(0.4)Sr_(0.6)MnO_3 could be a promising route to improve the catalytic activity.

关键词： ORR OER Perovskite Lithium-air batteries