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An Optimal FASA Approach for UAV Trajectory Tracking Control

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Guidance, Navigation and Control 2023年第3期3卷 1-23页

作者： gaoqi liu Bin Li Guangren Duan School of Aeronautics and Astronautics Sichuan University Chengdu 610000P.R.China Center for Control Theory and Guidance Technology Harbin Institute of Technology Haerbin 150000P.R.China Center for Control Science and Technology Southern University of Science and Technology Shenzhen 518055 P.R.China

In this paper,a fully actuated system approach(FASA)-based control scheme is proposed for the trajectory tracking of a quadrotor unmanned aerial vehicle(UAV).System uncertainty,external disturbance and actuator constraint are all considered,which make the problem *** by the active disturbance rejection control(ADRC),tracking di®erentiator(TD)and extended state observer(ESO)are introduced for handling the uncertainties and generating the feedback *** the proposed feedback control law,the performance of the resulted closed loop system is related to its eigenstructure-eigenvalue and *** on a type of control parametrization method,the parametrized eigenstructure of the closed loop system are optimized.A better performance is observed by comparative numerical simulation.

关键词： Fully actuated second-order systems parametric control approach quadrotor trajectory tracking.

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输入受限下的四旋翼飞行器姿态参数化控制

电光与控制 2023年第1期30卷 63-68页

作者：刘高旗四川大学空天科学与工程学院成都610000

针对四旋翼无人机在输入受限情况下的姿态跟踪控制问题,提出了一种参数化控制方法。首先建立了四旋翼姿态误差二阶全驱模型,采用一种参数化控制器,使姿态误差系统等价于一阶定常闭环系统,从而实现姿态角收敛至跟踪信号。考虑四旋翼输入... 详细信息

针对四旋翼无人机在输入受限情况下的姿态跟踪控制问题,提出了一种参数化控制方法。首先建立了四旋翼姿态误差二阶全驱模型,采用一种参数化控制器,使姿态误差系统等价于一阶定常闭环系统,从而实现姿态角收敛至跟踪信号。考虑四旋翼输入受限及更好的跟踪性能,采用智能优化的方法,利用粒子群算法优化控制律中的参数矩阵。仿真实验表明:与反步法相比,提出的参数化控制器能够在输入受限情况下更快速地跟踪姿态指令,具有更好的暂态性能,实现了四旋翼高精度姿态跟踪控制。

关键词：四旋翼无人机输入受限参数化控制

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Surface heterojunction based on n-type low-dimensional perovskite film for highly efficient perovskite tandem solar cells

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National Science Review 2024年第5期11卷 244-253页

作者： Xianyuan Jiang Qilin Zhou Yue Lu Hao Liang Wenzhuo Li Qi Wei Mengling Pan Xin Wen Xingzhi Wang Wei Zhou Danni Yu Hao Wang Ni Yin Hao Chen Hansheng Li Ting Pan Mingyu Ma gaoqi liu Wenjia Zhou Zhenhuang Su Qi Chen Fengjia Fan Fan Zheng Xingyu Gao Qingqing Ji Zhijun Ning School of Physical Science and Technology Shanghai Tech University Department of Modern Physics University of Science and Technology of China i-Lab CAS Key Laboratory of Nanophotonic Materials and Devices Suzhou Institute of Nano-Tech and Nano-Bionics Shanghai Synchrotron Radiation Facility (SSRF) Shanghai Advanced Research InstituteChinese Academy of Sciences

Enhancing the quality of junctions is crucial for optimizing carrier extraction and suppressing recombination in semiconductor devices. In recent years, metal halide perovskite has emerged as the most promising next-generation material for optoelectronic devices. However, the construction of high-quality perovskite junctions, as well as characterization and understanding of their carrier polarity and density,remains a challenge. In this study, using combined electrical and spectroscopic characterization techniques,we investigate the doping characteristics of perovskite films by remote molecules, which is corroborated by our theoretical simulations indicating Schottky defects consisting of double ions as effective charge *** a post-treatment process involving a combination of biammonium and monoammonium molecules, we create a surface layer of n-type low-dimensional perovskite. This surface layer forms a heterojunction with the underlying 3D perovskite film, resulting in a favorable doping profile that enhances carrier extraction. The fabricated device exhibits an outstanding open-circuit voltage(VOC) up to 1.34 V and achieves a certified efficiency of 19.31% for single-junction wide-bandgap（1.77 eV） perovskite solar cells, together with significantly enhanced operational stability, thanks to the improved separation of carriers. Furthermore, we demonstrate the potential of this wide-bandgap device by achieving a certified efficiency of 27.04% and a VOCof 2.12 V in a perovskite/perovskite tandem solar cell configuration.

关键词： perovskite solar cells field effect transistors heterojunction

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土工格栅加筋边坡水平变形有限元分析

人民黄河 2017年第10期39卷 106-109页

作者：曹磊孟宪金刘高启黄河水利职业技术学院土木与交通工程学院河南开封475004 开封公路管理局杞县分局河南开封475200

应用有限元软件对某一土工格栅加筋边坡进行有限元分析,对边坡水平变形在加筋层数、筋材位置、筋材长度、筋材模量发生变化时的规律开展了讨论。研究表明:筋材集中于边坡中下部对边坡水平位移所起到的约束作用较显著;在一定范围内,增大... 详细信息

应用有限元软件对某一土工格栅加筋边坡进行有限元分析,对边坡水平变形在加筋层数、筋材位置、筋材长度、筋材模量发生变化时的规律开展了讨论。研究表明:筋材集中于边坡中下部对边坡水平位移所起到的约束作用较显著;在一定范围内,增大加筋层数、筋材长度与筋材模量都可以有效地减小边坡水平位移。

关键词：土工格栅边坡有限元法水平变形

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变频器在电气传动自动控制中的应用

电气传动自动化 2021年第3期43卷 40-42页

作者：刘高奇酒钢(集团)宏联自控有限责任公司甘肃嘉峪关735100

随着电气传动自动化技术的不断成熟,我国机械设备的自动化水平越来越高,变频器也随着电气传动自动控制应用范围的不断扩大而得到了更广泛的应用。通过在电气设备中应用变频器,可有效地提高电气设备的应用效率,减少设备的故障率,还能在... 详细信息

随着电气传动自动化技术的不断成熟,我国机械设备的自动化水平越来越高,变频器也随着电气传动自动控制应用范围的不断扩大而得到了更广泛的应用。通过在电气设备中应用变频器,可有效地提高电气设备的应用效率,减少设备的故障率,还能在必要的情况下对设备运行进行节能降耗操作,对生产企业和生产中的电气传动设备来说都具有非常重要的意义。

关键词：变频器电气传动自动控制应用

KOH活化法制备煤基活性炭及其吸附性能研究

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化工新型材料 2018年第4期46卷 157-160页

作者：丁赛赛刘高旗许红亮杨碧野郑州大学材料科学与工程学院郑州450001 苏州市湘园特种精细化工有限公司苏州215001

研究了以无烟煤为原料,通过预炭化、再采用KOH活化法制备煤基活性炭的工艺。利用场发射扫描电子显微镜(SEM)研究了活性炭的显微结构,并测试了活性炭对甲基橙(MO)的吸附性能。结果表明:无烟煤炭化产物与KOH质量比(炭碱比)、活化温度、活... 详细信息

研究了以无烟煤为原料,通过预炭化、再采用KOH活化法制备煤基活性炭的工艺。利用场发射扫描电子显微镜(SEM)研究了活性炭的显微结构,并测试了活性炭对甲基橙(MO)的吸附性能。结果表明:无烟煤炭化产物与KOH质量比(炭碱比)、活化温度、活化时间对煤基活性炭显微结构及吸附性能有显著影响。在炭碱比为1∶1、活化温度为900℃、活化时间1h的条件下,能制备出吸附性能良好的活性炭材料,吸附15min时对MO的吸附率可达到89.6%。

关键词：无烟煤 KOH活化活性炭吸附性能

Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 509-521页

作者： Xinyuan Wang Fan Zhang Xingyu Zhou Qian Wang Changyu liu Yangyang liu Hui Wang Xiaojie liu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory （DFT） and finite element simulations show that incorporating SO42-into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g-1) and cycling stability (111.0 mAh g-1capacity after 1000 cycles at 10 C current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode

Weighted symbol-flipping decoding algorithm for nonbinary LDPC codes with flipping patterns

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Journal of Systems Engineering and Electronics 2011年第5期22卷 848-855页

作者： Bing liu Jun Gao Wei Tao gaoqi Dou Marine Communication Technology Institute Beijing 100841 P. R. China Electronic College of Engineering Naval University of Engineering Wuhan 430033 E R. China China Marine Development and Research Center Beijing 100161 E R. China

A novel low-complexity weighted symbol-flipping algorithm with flipping patterns to decode nonbinary low-density parity-check codes is proposed. The proposed decoding procedure updates the hard-decision received symbol vector iteratively in search of a valid codeword in the symbol vector space. Only one symbol is flipped in each iteration, and symbol flipping function, which is employed as the symbol flipping metric, combines the number of failed checks and the reliabilities of the received bits and calculated symbols. A scheme to avoid infinite loops and select one symbol to flip in high order Galois field search is also proposed. The design of flipping pattern＇s order and depth, which is dependent of the computational requirement and error performance, is also proposed and exemplified. Simulation results show that the algorithm achieves an appealing tradeoff between performance and computational requirement over relatively low Galois field for short to medium code length.

关键词： nonbinary low-density parity-check (LDPC) codes quasi-cyclic symbol-flipping (SF) decoding.

Role of the Greenland Sea ice anomaly in the late-spring drought over Northwest China

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 1-5页

作者： Yang liu Huopo Chen Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University for Information Science and TechnologyNanjingChina

Drought across Northwest China in late spring has exerted a vital effect on the local climate and agricultural production,and has been alleviated during the past *** study explored the influence of the preceding Arctic sea ice on the May drought in Northwest China caused by the precipitation *** analysis indicated that when the Greenland Sea ice concentration is abnormally high during February to April,the dry conditions in Northwest China tend to be *** increase of sea ice in the Greenland Sea can excite a meridional circulation,which causes sea surface temperature(SST)anomalies in the North Atlantic via the sea-air interaction,manifested as significant warm SST anomalies over the south of Greenland and the subtropical North Atlantic,but negative SST anomalies over the west of the *** abnormal SST pattern maintains to May and triggers a zonal wave train from the North Atlantic through Scandinavia and Central Asia to Northwest China,leading to abnormal cyclones in Northwest ***,Northwest China experiences a more humid climate than usual.

关键词： Arctic sea ice Greenland Sea North Atlantic SST Drought Northwest China