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A review of aerial manipulation of small-scale rotorcraft unmanned robotic systems

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Chinese Journal of Aeronautics 2019年第1期32卷 200-214页

作者： Xilun DING Pin GUO Kun XU yushu yu Robotics Institute Beihang University Department of Mechanics and Maritime Sciences Chalmers University of Technology

Small-scale rotorcraft unmanned robotic systems(SRURSs) are a kind of unmanned rotorcraft with manipulating devices. This review aims to provide an overview on aerial manipulation of SRURSs nowadays and promote relative research in the future. In the past decade, aerial manipulation of SRURSs has attracted the interest of researchers globally. This paper provides a literature review of the last 10 years(2008–2017) on SRURSs, and details achievements and challenges. Firstly, the definition, current state, development, classification, and challenges of SRURSs are introduced. Then, related papers are organized into two topical categories: mechanical structure design, and modeling and control. Following this, research groups involved in SRURS research and their major achievements are summarized and classified in the form of tables. The research groups are introduced in detail from seven parts. Finally, trends and challenges are compiled and presented to serve as a resource for researchers interested in aerial manipulation of SRURSs. The problem,trends, and challenges are described from three aspects. Conclusions of the paper are presented,and the future of SRURSs is discussed to enable further research interests.

关键词： Aerial manipulation Mechanical structure design Modeling and control Research groups Small-scale rotorcraft unmanned aerial systems Trends and challenges

Ridge regression energy levels calculation of neutral ytterbium(Z=70)

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Chinese Physics B 2023年第3期32卷 196-204页

作者：余雨姝杨晨蒋刚 Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China Key Laboratory of High Energy Density Physics and Technology Ministry of EducationChengdu 610065China

In view of the difficulty in calculating the atomic structure parameters of high-Z elements,the Hartree–Fock with relativistic corrections(HFR)theory in combination with the ridge regression(RR)algorithm rather than the Cowan code’s least squares fitting(LSF)method is proposed and *** analyzing the energy level structure parameters of the HFR theory and using the fitting experimental energy level extrapolation method,some excited state energy levels of the Yb I(Z=70)atom including the 4f open shell are *** advantages of the ridge regression algorithm are demonstrated by comparing it with Cowan code’s LSF *** addition,the results obtained by the new method are compared with the experimental results and other theoretical results to demonstrate the reliability and accuracy of our approach.

关键词： atomic data ytterbium energy levels ridge regression algorithm

一种多旋翼多功能空中机器人及其腿式壁面行走运动规划

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航空学报 2010年第10期31卷 2075-2086页

作者：丁希仑俞玉树北京航空航天大学机器人研究所北京100191

提出了一种既可实现飞行功能又可实现壁面运动的多旋翼多功能空中机器人。设计了机器人的结构,分析了其工作原理,研究了机器人腿式壁面行走模式下腿/足与壁面接触时的机体动力学。结合多旋翼推进的机理对机器人在壁面运动模式下的步态... 详细信息

提出了一种既可实现飞行功能又可实现壁面运动的多旋翼多功能空中机器人。设计了机器人的结构,分析了其工作原理,研究了机器人腿式壁面行走模式下腿/足与壁面接触时的机体动力学。结合多旋翼推进的机理对机器人在壁面运动模式下的步态进行了规划,基于非线性轨迹线性化控制(TLC)法设计了空中机器人在步态过程中的姿态稳定控制器。在MATLAB环境下对机器人的腿式壁面运动进行了仿真分析研究,仿真结果表明了所设计的步态及其稳定控制方法的可行性。

关键词：旋翼飞行爬壁动力学运动规划控制

多飞行器集联平台的设计与轨迹线性化几何控制

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机械工程学报 2022年第21期58卷 16-26页

作者：俞玉树王凯迪杜健睿徐彬项昌乐北京理工大学机电学院北京100081 北京理工大学机械与车辆学院北京100081 北京理工大学重庆创新中心重庆401135

将多个无人机组合为“集联”飞行平台,能够解决单一无人机通常存在的欠驱动问题,实现六维全向运动,构建飞行操作平台。同时,多飞行器集联平台相比单一飞行器在带载能力、容错能力等方面具有优势。多飞行器集联平台的设计与控制是这一新... 详细信息

将多个无人机组合为“集联”飞行平台,能够解决单一无人机通常存在的欠驱动问题,实现六维全向运动,构建飞行操作平台。同时,多飞行器集联平台相比单一飞行器在带载能力、容错能力等方面具有优势。多飞行器集联平台的设计与控制是这一新型平台实现过程中的关键问题。设计了以三架子飞行器在星形连接形式下的集联平台结构,这一集联形式下,集联平台整体具备同时调整六维位置和姿态的能力。对集联平台整体系统进行动力学建模,进而设计了系统整体的控制器。为简化控制,采用奇异摄动理论的思想将整体系统分离为快变子系统和慢变子系统,其中快变子系统对应子飞行器的姿态运动,慢变子系统对应于集联平台的整体运动。由于飞行器的位形空间位于非欧空间,首次运用流形上的轨迹线性化控制设计了慢变子系统的控制器。基于Lyapunov稳定性理论证明了闭环系统的稳定性。采用现场总线技术设计了多个子飞行器间的实时、可扩展通信架构。在此基础上,开发研制了多飞行器集联平台的原理样机软硬件系统。通过仿真测试和样机上的实际飞行测试,验证了集联平台设计与控制方法的有效性。这些工作为发展具备六维全向运动、可拓展的多飞行器集联平台奠定了理论和实验基础。

关键词：多飞行器集联平台六维全向运动几何控制总线通信实际飞行测试

Automatic Measurement of Silicon Lattice Spacings in High-Resolution Transmission Electron Microscopy Images Through 2D Discrete Fourier Transform and Inverse Discrete Fourier Transform

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Nanomanufacturing and Metrology 2022年第2期5卷 119-126页

作者： Fang Wang yushu Shi Shu Zhang Xixi yu Wei Li National Institute of Metrology Beijing100029China Shenzhen Institute for Technology Innovation National Institute of MetrologyShenzhen518038China

Line width(i.e.,critical dimension,CD)is a crucial parameter in integrated *** accurately control the CD in manufacturing,a reasonable CD measurement algorithm is *** develop an automatic and accurate method based on a two-dimensional discrete Fourier transform for measuring the lattice spacings from high-resolution transmission electron microscopy *** the two-dimensional inverse discrete Fourier transform of the central spot and a pair of symmetrical diffraction spots,an image containing only a set of lattice spacings is ***,the pixel span of the lattice spacing is calculated through the centre of gravity ***,we estimate the standard CD value according to the half-intensity *** silicon crystal lattice constant guarantees the accuracy and traceability of the CD *** experiments,we demonstrate the efficiency of the proposed method,which can be conveniently applied to accurately measure CDs in practical applications.

关键词： Transmission electron microscopy Line width Crystal lattice constant Traceability

Evaluation of the Biodiversity Conservation Function in Liaohe Delta Wetland,Northeastern China

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Journal of Meteorological Research 2020年第4期34卷 798-805页

作者： Wenying yu Ruipeng JI Xiuzhen HAN Long CHEN Rui FENG Jinwen WU yushu ZHANG Institute of Atmospheric Environment China Meteorological AdministrationShenyang 110166 Key Laboratory of Agrometeorological Disasters of Liaoning Province Shenyang 110166 National Satellite Meteorological Center Beijing 100081 Panjin Meteorological Bureau Panjin 124010

The scientific evaluation of the wetland biodiversity conservation function is the basis of balanced wetland protection and development. Our research sought to provide references for the protection of wetland ecological environments as well as the related planning and management policies. The study established a fitting model for evaluating the biodiversity conservation function in the Liaohe Delta, northeastern China. The new model, the Wetland Biodiversity Conservation Indicator(WBCI), was with four input factors, including the vegetation coverage(VC), habitat suitability index(HI), land use and land cover(LULC) index(LI), and threat factor index(TI) of the LULC type. The values assigned to HI and TI were based on Integrated Valuation of Ecosystem Services and Tradeoffs(In VEST)habitat quality models. The weights of all the factors in WBCI were valued with the Principal Component Analysis(PCA). We evaluated the wetland biodiversity conservation function of Panjin, Liaohe Delta, China, by using the WBCI model based on Gaofen-1(GF-1) satellite data in 2018, and the result was verified with In VEST and other models. It showed that the output map was similar to that of In VEST, with the higher-quality habitat including the wetland, tidal flat, water body, and forest, as well as the lower-quality land use types including the paddy field, crop field, construction land, and land used by traffic. The wetland biodiversity conservation function was better in areas less affected by human disturbance, with very abundant species and good-quality habitat. It was poor in areas impacted by more frequent human activities such as the land cultivation, housing, and traffic, which led to the landscape fragmentation. The WBCI model provided a more accurate reflection of the bird distribution than the In VEST model. The WBCI model was able to reflect the difference in quality of each habitat grade, in contrast to the net primary productivity(NPP) method and species distribution models(

关键词： wetland biodiversity conservation function habitat quality evaluation

Dynamic Response of Phragmites australis and Suaeda salsa to Climate Change in the Liaohe Delta Wetland

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Journal of Meteorological Research 2021年第1期35卷 157-171页

作者： yushu ZHANG Wenying yu Ruipeng JI Yijun ZHAO Rui FENG Qingyu JIA Jinwen WU Institute of Atmospheric Environment China Meteorological AdministrationShenyang 110166 Key Laboratory of Agrometeorological Disasters of Liaoning Province Shenyang 110166 Panjin Meteorological Service Center Liaoning Meteorological BureauPanjin 124010

Because of its unique geographical location and ecological function, the Liaohe Delta Wetland is important in maintaining regional ecological balance and security. Monitoring and evaluating changes in the wetland are therefore of great importance. We used medium-and high-resolution satellite data, meteorological station data, and site measurement data to analyze changes in the area and spatial distribution of Phragmites australis and Suaeda salsa in the Liaohe Delta Wetland from 1998 to 2017, as well as their growth response to the climate change. The results showed that during 1998–2017, the areas of both P. australis and S. salsa wetlands alternated through periods of decreasing,increasing, and then decreasing trends. The annual change in the area and spatial distribution range of S. salsa fluctuated more than that of P. australis. The annual variation of normalized difference vegetation index(NDVI) in P. australis wetland showed an upward trend from 1998 to 2017. The area of P. australis cover that was improved, unchanged, and decreased accounted for 81.8%, 12.3%, and 5.9%, respectively, of the total area;evaporation and wind speed were the main meteorological factors affecting the NDVI;and contribution rates of the climate change and human activities to the NDVI were 73.2% and 26.8%, respectively. The area with vegetation cover being mainly *** that was improved, unchanged, and decreased accounted for 63.3%, 18.3%, and 18.4%, respectively, of the total area;and no meteorological factors significantly affected the NDVI of S. salsa in the region. The interaction between vegetation growth and meteorological factors may help to explain the increasing trend in vegetation *** improvement in wetland vegetation also led to carbon sequestration and an increase in sequestration capacity.

关键词： Liaohe Delta wetland Phragmites australis Suaeda salsa climate change

Variability of soil organic carbon reservation capability between coastal salt marsh and riverside freshwater wetland in Chongming Dongtan and its microbial mechanism

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Journal of Environmental Sciences 2012年第6期24卷 1053-1063页

作者： yu Hu Yanli Li Lei Wang yushu Tang Jinhai Chen Xiaohua Fu Yiquan Le Jihua Wu State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China School of Life Science Fudan UniversityShanghai 200433China

Two representative zones in Chongming Dongtan which faced the Yangtze River and East China Sea respectively were selected to study the variability of soil organic carbon （SOC） reservation capability between coastal wetland and riverside wetland in the Chongming Dongtan wetland as well as its mechanism by analyzing soil characteristics and plant *** results showed the SOC content of riverside wetland was only 48.61% （P=0.000 〈 0.05） that of coastal *** the organic matter inputs from plant litter of the coastal wetland and riverside wetland were approximately the same,the higher soil microbial respiration （SMR） of riverside wetland led to its lower SOC reservation *** the riverside wetland,the high soil microbial biomass,higher proportion of β-Proteobacteria,which have strong carbon metabolism activity and the existence of some specific aerobic heterotrophic bacteria such as Bacilli and uncultured Lactococcus,were the important reasons for the higher SMR compared to the coastal *** were additional differences in soil physical and chemical characteristics between the coastal wetland and riverside *** analysis of predominant bacteria and microbial biomass showed that soil salinity influenced β-Proteobacteria and microbial biomass most negatively among these physical and chemical *** the low salinity of the riverside area was suitable for the growth of microorganisms,especially β-Proteobacteria and some specific bacteria,which led to the high SMR and low SOC reservation capability when compared to the coastal area.

关键词： soil organic carbon carbon reservation capability community diversity coastal wetland riverside wetland ChongmingDongtan

Monitoring of edema progression in permanent and transient MCAO model using SS-OCT

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Journal of Innovative Optical Health Sciences 2021年第1期4卷 63-71页

作者： Yao yu Ziyue Meng Ang Li Yang Lin Jian Liu yushu Ma Yi Wang Zhenhe Ma School of Control Engineering Northeastern University at Qinhuangdao Qinhuangdao 066004P.R.China School of Computer Science and Engineering Northeastern University Shenyang 110169P.R.China

Cerebral edema is a severe complication of acute ischemic stroke with high mortality but limited *** parameters such as brain water content and intracranial pressure may represent the global assessment of edema,optical properties can appear heterogeneously throughout the cerebral tissue relative to the site of *** this study,we have monitored the edema formation and progression in both permanent and transient middle cerebral artery oc-clusion models in *** was reflected by the decrease of optical attenuation coefficient(OAC)value in OCT *** utilizing swept-source optical coherence tomography(SS-OCT),we found that in photochemically induced permanent focal stroke model,both the edema size and edema index,steadily developed until the end of monitor(7 h).Comparatively,when transient ischemia was introduced with endothelin-1(ET-1),the edema was detected as early as 15 min,and began to recover after 30 min until monitor was finished(3 h).Despite the majority of the edema being recovered to some extent,the condition of a small region within the edema kept deteriorating,presumably due to the reperfusion damage which might result in serious clinical *** study has compared the edema characteristics from two different acute ischemic stroke *** work not only confirms the capability of OCT to temporal and spatial monitor of edema but is also able to locate focal conditions at some areas that might highly determine the prognosis and treatment decisions.

关键词： Swept-source optical coherence tomography ischemic stroke cerebral edema optical attenuation coefficient middle cerebral artery occlusion