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Chinese Physics Letters 2001年第12期18卷 1641-1643页

作者： zheng ze-wei SHEN Bo JIANG Chun-Ping ZHANG Rong SHI Yi zheng You-Dou zheng Guo-Zhen GUO Shao-Ling CHU Jun-Hao National Laboratory of Solid State Microstructures and Department of Physics Nanjing UniversityNanjing 210093 National Laboratory for Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083

In the magnetotransport measurements of the two-dimensional electron gas (2DEG) in modulation-doped Al_(0.22)Ga_(0.7)sN/C heterostructures, a new magnetoresistance oscillation of the 2DEG is observed at low magnetic fields when the Al_(0.22)Ga_(0.7)sN layer on GaN is partially relaxed. It is thought that the misfit dislocations induced by the partially relaxed Al_(0.22)Ga_(0.7)sN layer modulate the distribution of the piezoelectric polarization-induced charges at the Al0.22Ga0.7sN/GaN heterointerface, and thus produce a strong modulation potential at the heterointerface. The strong modulation potential results in the novel magnetoresistance oscillation of the 2DEG at low magnetic fields.

关键词： N/Ga polarization relaxed

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非完整移动机器人人全全局路径跟踪控制

控制理论与应用 2012年第6期29卷 741-746页

作者：郑泽伟霍伟诸兵北京航空航天大学飞行器控制一体化技术重点实验室航空科学与工程学院北京100191 北京航空航天大学飞行器控制一体化技术重点实验室第七研究室北京10019I

根据制导路径跟踪理论,提出了一种非完整移动机器人全局路径跟踪控制方法.这一方法首先在路径坐标系上计算实际位置与期望位置的误差,利用制导的路径跟踪理论,导出消除该误差所需的姿态角和路径参数更新律,然后据此求解角速度及实际控制... 详细信息

根据制导路径跟踪理论,提出了一种非完整移动机器人全局路径跟踪控制方法.这一方法首先在路径坐标系上计算实际位置与期望位置的误差,利用制导的路径跟踪理论,导出消除该误差所需的姿态角和路径参数更新律,然后据此求解角速度及实际控制.文中还给出了初始路径参考点的计算方法,分析了路径跟踪方向和反转方法.稳定性分析证明该方法没有控制奇异点,受控闭环系统全局一致渐近稳定.最后通过移动机器人典型路径跟踪实验验证了所提出方法的可行性.

关键词：路径跟踪基于制导移动机器人跟踪方向

Effect of a Carbon Fibre-steel Fibre-graphite Conductive Filler on the Electrothermal Properties of Cementitious Materials

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 141-151页

作者： FAN Yanan wei Hong zheng Hongyong DU Hongxiu Department of Architecture and Environmental Engineering Taiyuan UniversityTaiyuan 030032China College of Civil Engineering Taiyuan University of TechnologyTaiyuan 030032China

Carbon fibre,steel fibre and graphite were used as conductive fillers to prepare cementitious materials with excellent electrothermal *** electrically conductive cementitious materials with different volume dosages were analysed through compressive and flexural strength,electrochemical impedance spectroscopy and temperature rise *** equivalent circuit model was established to study the electrically conductive heat generation mechanism in the electrically conductive cementitious *** results indicate that the mechanical properties of cementitious composite materials with a ternary conductive phase are better than those of pristine cementitious materials because the fibrous filler improves their mechanical ***,the incorporation of graphite in the material reduces its *** fibrous and point-like conductive phase materials into the cementitious material enhances the overall conductive pathway and considerably reduces the electrical resistance of the cementitious material,enhancing its conductive *** volume ratios of carbon fibre,steel fibre and graphite that achieve an optimal complex doping in the cementitious material were 0.35%,0.6%and 6%,*** was determined using the mutation point of each circuit element parameter as the percolation *** addition,at a certain safety voltage,there is a uniform change between the internal and surface temperatures of the conductive cementitious material,and the heating effect in this materialis is considerably better than that in the pristine cementitious material.

关键词： cementitious composites conductive fillers electrothermal properties electrochemical impedance spectroscopy

AI-Enhanced Secure Data Aggregation for Smart Grids with Privacy Preservation

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Computers, Materials & Continua 2025年第1期82卷 799-816页

作者： Congcong Wang Chen Wang Wenying zheng wei Gu School of Software Nanjing University of Information Science and TechnologyNanjing210044China School of Information Science and Engineering Zhejiang Sci-Tech UniversityHangzhou310018China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China School of Computer Science and Technology(School of Artificial Intelligence) Zhejiang Sci-Tech UniversityHangzhou310018China School of Computer Science(School of Cyber Science and Engineering) Nanjing University of Information Science and TechnologyNanjing210044China

As smart grid technology rapidly advances,the vast amount of user data collected by smart meter presents significant challenges in data security and privacy *** research emphasizes data security and user privacy concerns within smart ***,existing methods struggle with efficiency and security when processing large-scale *** efficient data processing with stringent privacy protection during data aggregation in smart grids remains an urgent *** paper proposes an AI-based multi-type data aggregation method designed to enhance aggregation efficiency and security by standardizing and normalizing various data *** approach optimizes data preprocessing,integrates Long Short-Term Memory(LSTM)networks for handling time-series data,and employs homomorphic encryption to safeguard user *** also explores the application of Boneh Lynn Shacham(BLS)signatures for user *** proposed scheme’s efficiency,security,and privacy protection capabilities are validated through rigorous security proofs and experimental analysis.

关键词： Smart grid data security privacy protection artificial intelligence data aggregation

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ZnCdTe-ZnTe多量子阱的谱线增宽

半导体光电 1999年第6期20卷 413-415页

作者：郑泽伟范希武郑宏杨宝均空军气象学院南京211101 中国科学院长春物理研究所长春130021

通过对ＺｎｘＣｄ１－ｘＴｅ－ＺｎＴｅ多量子阱的光致发光研究，讨论了该材料的谱线增宽效应。指出材料阱层的组分涨落是激子谱线非均匀增宽的主要来源，而由流体力学性质决定的涨落，在组分张落中起着非常重要的作用。

关键词：多量子阱激子非均匀增宽组分涨落

兴边强边进程中边境口岸管理的政策制约因素研究

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北方民族大学学报（哲学社会科学版） 2021年第2期 5-14页

作者：高永久郑泽玮南开大学太和智库边疆发展研究中心天津300351 南开大学周恩来政府管理学院天津300351

兴边富民行动计划的实施对边境口岸治理具有重要的现实意义,研究表明,国家治理体系的制度安排是边境口岸可持续发展的保障。当前,现行政策在加强口岸建设、推进兴边强边政策进程中受到边贸优惠政策、地缘政治风险、边境口岸城镇文化建... 详细信息

兴边富民行动计划的实施对边境口岸治理具有重要的现实意义,研究表明,国家治理体系的制度安排是边境口岸可持续发展的保障。当前,现行政策在加强口岸建设、推进兴边强边政策进程中受到边贸优惠政策、地缘政治风险、边境口岸城镇文化建设、社会民生建设和资源分配方面的宏观制度设计等因素的影响。通过兴边强边,不仅带动了边境口岸的发展,也拓宽了边境口岸基层地方治理能力的提升路径。

关键词：边境口岸管理治理体系治理能力兴边富民

Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 58-69页

作者： Jie Wang wei Wang Xuheng Chen Junfang Bao Qiuyue Hao Heng zheng Runsheng Xu School of Chemistry and Materials Science Hubei Engineering UniversityXiaogan 432000China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China Institue of Ironmaking Technology Baosteel Central Research InstituteShanghai 201999China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The utilization of iron coke provides a green pathway for low-carbon *** uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was ***,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric *** findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and *** provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron *** the heating rate in non-isothermal gasification can enhance the reactivity of iron *** metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon *** kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore ***,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%.

关键词： low-carbon ironmaking iron coke gasification structural evolution kinetic model

Si调制掺杂AlGaN/GaN异质结磁阻拍频现象

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物理学报 2005年第5期54卷 2247-2251页

作者：姚炜仇志军桂永胜郑泽伟吕捷唐宁沈波褚君浩中国科学院上海技术物理研究所红外物理国家重点实验室上海200083 南京大学物理系南京210093

在低温 (1 5K— 2 5K)和强磁场 (0— 10T)条件下 ,对二维电子气占据两个子带的Si调制掺杂AlGaN GaN异质结构进行磁输运测量 .在一定温度范围内观察到磁阻拍频现象 .根据Sander等人和Raikh等人给出的磁阻振荡的具体表达式 ,拟合实验结果... 详细信息

在低温 (1 5K— 2 5K)和强磁场 (0— 10T)条件下 ,对二维电子气占据两个子带的Si调制掺杂AlGaN GaN异质结构进行磁输运测量 .在一定温度范围内观察到磁阻拍频现象 .根据Sander等人和Raikh等人给出的磁阻振荡的具体表达式 ,拟合实验结果表明磁阻拍频是由第一子带SdH振荡和磁致子带间散射引起的磁阻振荡导致的 .

关键词：氮化镓异质结构 SdH振荡 .磁致子带间散射磁阻拍频半导体

Joint Probabilistic Scheduling and Resource Allocation for Wireless Networked Control Systems

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 258-260页

作者： Meng zheng Lei Zhang wei Liang IEEE the State Key Laboratory of Robotics and the Key Laboratory of Networked Control Systems Shenyang Institute of Automation Chinese Academy of Sciences the University of Chinese Academy of Sciences

Dear Editor,This letter presents a joint probabilistic scheduling and resource allocation method(PSRA) for 5G-based wireless networked control systems(WNCSs). As a control-aware optimization method, PSRA minimizes the linear quadratic Gaussian(LQG) control cost of WNCSs by optimizing the activation probability of subsystems, the number of uplink repetitions, and the durations of uplink and downlink phases. Simulation results show that PSRA achieves smaller LQG control costs than existing works.

关键词：

Passive activity enhances residual control ability in patients with complete spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2337-2347页

作者： Yanqing Xiao Mingming Gao zejia He Jia zheng Hongming Bai Jia-Sheng Rao Guiyun Song wei Song Xiaoguang Li Beijing Key Laboratory for Biomaterials and Neural Regeneration Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Rehabilitation Evaluation China Rehabilitation Research CenterBeijingChina Cardiac Center Beijing Children’s HospitalCapital Medical UniversityBeijingChina The State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Department of Rehabilitation Engineering China Rehabilitation Science InstituteBeijingChina

Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury ***,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface *** this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord *** patients with chronic complete thoracic spinal cord injury were *** electromyography data from eight major leg muscles were acquired and compared before and after the passive activity *** results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of *** the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically *** findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.

关键词： complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task