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Modeling and Robust Backstepping Sliding Mode Control with Adaptive RBFNN for a Novel Coaxial Eight-rotor UAV

IEEE/CAA Journal of Automatica Sinica 2015年第1期2卷 56-64页

作者： Cheng Peng yue bai Xun Gong Qingjia Gao Changjun Zhao Yantao Tian the Department of Control Science and Engineering Jilin University the Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences

This paper focuses on the robust attitude control of a novel coaxial eight-rotor unmanned aerial vehicles (UAV) which has higher drive capability as well as greater robustness against disturbances than quad-rotor UAV. The dynamical and kinematical model for the coaxial eight-rotor UAV is developed, which has never been proposed before. A robust backstepping sliding mode controller (BSMC) with adaptive radial basis function neural network (RBFNN) is proposed to control the attitude of the eightrotor UAV in the presence of model uncertainties and external disturbances. The combinative method of backstepping control and sliding mode control has improved robustness and simplified design procedure benefiting from the advantages of both controllers. The adaptive RBFNN as the uncertainty observer can effectively estimate the lumped uncertainties without the knowledge of their bounds for the eight-rotor UAV. Additionally, the adaptive learning algorithm, which can learn the parameters of RBFNN online and compensate the approximation error, is derived using Lyapunov stability theorem. And then the uniformly ultimate stability of the eight-rotor system is proved. Finally, simulation results demonstrate the validity of the proposed robust control method adopted in the novel coaxial eight-rotor UAV in the case of model uncertainties and external disturbances. © 2014 Chinese Association of Automation.

关键词： Adaptive control systems Aircraft control Approximation algorithms Attitude control Backstepping Controllers Functions Learning algorithms Radial basis function networks Robust control Robustness (control systems) Sliding mode control Uncertainty analysis

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Altitude information fusion method and experiment for UAV

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High Technology Letters 2017年第2期23卷 165-172页

作者：徐东甫 Pei Xinbiao bai yue Peng Cheng Wu Ziyi Xu Zhijun Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 P. R. China University of Chinese Academy of Sciences Beijing 100039 P. R. China

Altitude regulation is a fundamental problem in UAV(unmanned aerial vehicles) control to ensure hovering and autonomous navigation ***,data from altitude sensors may be unstable by interference.A digital-filter-based improved adaptive Kalman method is proposed to improve accuracy and reliability of the altitude measurement information.A unique sensor data fusion structure is designed to make different sensors switch automatically in different *** and experimental results show that an improved Sage-Husa adaptive extended Kalman filter(SHAEKF) is adopted in altitude data fusion which means that altitude error is limited to 1.5m in high altitude and 1.2m near the *** method is proved feasible and effective through hovering flight test and three-dimensional track flight experiment.

关键词： unmanned aerial vehicles(UAV) altitude information fusion multi-sensor adaptive Kalman filter

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Sensor-Based Inspection of the Formation Accuracy in Ultra-Precision Grinding （UPG） of Aspheric Surface Considering the Chatter Vibration

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Photonic Sensors 2018年第2期8卷 97-102页

作者： Yao LEI yue bai Zhijun XU School of Mechanical Engineering and Automation Fuzhou University Fuzhou 350116 China Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130022 China

This paper proposes an experimental approach for monitoring and inspection of the formation accuracy in ultra-precision grinding （UPG） with respect to the chatter vibration. Two factors related to the grinding progress, the grinding speed of grinding wheel and spindle, and the oil pressure of the hydrostatic bearing are taken into account to determining the accuracy. In the meantime, a mathematical model of the radius deviation caused by the micro vibration is also established and applied in the experiments. The results show that the accuracy is sensitive to the vibration and the forming accuracy is much improved with proper processing parameters. It is found that the accuracy of aspheric surface can be less than 4 μm when the grinding speed is 1400r/min and the wheel speed is 100 r/min with the oil pressure being 1.1 MPa.

关键词： Optical aspheric surface micro-vibrations ultra-precision grinding formation accuracy grindingspeed

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Wood forming tissue-specific expression of PdSuSy and HCHL increases holocellulose content and improves saccharification in Populus

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Journal of Forestry Research 2021年第4期32卷 1681-1688页

作者： Yang Zhang Hua Xu Yingzhen Kong Jiawen Hua Xianfeng Tang Yamei Zhuang yue bai Gongke Zhou Guohua Chai University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Key Laboratory of Biofuels Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101People’s Republic of China Shandong Provincial Key Laboratory of Energy Genetics Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101People’s Republic of China College of Agronomy Qingdao Agricultural UniversityQingdao 266109People’s Republic of China Forestry College Inner Mongolia Agricultural UniversityHuhhot 010018People’s Republic of China College of Resources and Environment Qingdao Agricultural UniversityQingdao 266109People’s Republic of China

Development of strategies to deconstruct lignocellulosic biomass in tree species is essential for biofuels and biomaterials *** applied a wood forming tissue-specific system in a hybrid poplar to express both PdSuSy(a sucrose synthase gene from Populus deltoides×*** that has not been functionally characterized)and HCHL(the hydroxycinnamoyl-CoA hydratase-lyase gene from Pseudomonas fluorescens,which inhibits lignin polymerization in Arabidopsis).The PdSuSy-HCHL overexpression poplars correspondingly driven by the promoters of Arabidopsis AtCesA7 and AtC4 H resulted in a significant increase in cellulose(>8%),xylan(>12%)and glucose(>29%)content,accompanying a reduction in galacturonic acid(>36%)content,compared to control *** saccharification efficiency of these overexpression poplars was dramatically increased by up to 27%,but total lignin content was *** transgenic poplars showed inhibited growth characteristics,including>16%reduced plant height,>10% reduced number of internodes,and>18% reduced fresh weight after growth of 4 months,possibly due to relatively low expression of HCHL in secondary *** results demonstrate the structural complexity and interaction of the cell wall polymers in wood tissue and outline a potential method to increase biomass saccharification in woody species.

关键词： Saccharification Biomass Cell wall composition Growth Poplar

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Mild and efficient recovery of lithium-ion battery cathode material by deep eutectic solvents with natural and cheap components

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Green Chemical Engineering 2023年第3期4卷 303-311页

作者： Yu Chen Yanlong Wang yue bai Minghui Feng Fengyi Zhou Yanhong Lu Yuting Guo Yixuan Zhang Tiancheng Mu Department of Chemistry and Material Science Langfang Normal UniversityLangfang065000China Hebei Regional Geological Survey Institute Langfang065000China Department of Chemistry Renmin University of ChinaBeijing100872China

Dissolution of lithium cobalt oxide(LCO)is the key step for the recovery of valuable metals(e.g.,Co and Li)from spent LCO-based lithium-ion batteries(LIBs).However,the dissolution process of LCO either needs toxic solvents,and high temperature,or shows low *** eutectic solvents(DESs)are potential green solvents to dissolve ***,DESs with polyethylene glycol(PEG)as hydrogen bond acceptor and ascorbic acid(AA)as hydrogen bond donor are found to dissolve LCO with 84.2%Co leaching efficiency at 80℃ and 72 h,which is higher than that from the reported references by common ***,both DESs components(i.e.,PEG and AA)are cheap,biodegradable,and *** could be easily and abundantly extracted from natural fruits or *** provides a new guide for the green,mild,and efficient dissolution of LCO aiming at sustainable recovery of spent LIBs.

关键词： Low cost Mild condition New energy Green chemistry Green solvents Ascorbic acid

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Improvement of human embryonic stem cell-derived retinal pigment epithelium cell adhesion, maturation, and function through coating with truncated recombinant human vitronectin

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International Journal of Ophthalmology(English edition) 2021年第8期14卷 1160-1167页

作者： Xin-yue Zhu Yu-Hong Chen Ting Zhang Su-Jun Liu Xin-yue bai Xian-Yu Huang Mei Jiang Xiao-Dong Sun Department of Ophthalmology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China National Clinical Research Center for Eye Diseases Shanghai 200080China Shanghai Key Laboratory of Fundus Diseases Shanghai 200080China Shanghai Engineering Center for Visual Science and Photomedicine Shanghai 200080China

AIM:To explore an xeno-free and defined coating substrate suitable for the culture of H9 human embryonic stem cell-derived retinal pigment epithelial(hES-RPE)cells in vitro,and compare the behaviors and functions of h ESRPE cells on two culture substrates,laminin521(LN-521)and truncated recombinant human vitronectin(VTN-N).METHODS:hES-RPE cells were used in the *** abilities of LN-521 and VTN-N at different concentrations to adhere to hES-RPE cells were compared with a high-content imaging *** real-time polymerase chain reaction was used to evaluate RPE-specific gene expression levels midway(day 10)and at the end(day 20)of the time *** polarity was observed by immunofluorescent staining for apical and basal markers of the *** phagocytic ability of hES-RPE cells was identified by flow cytometry and ***:The cell adhesion assay showed that the ability of LN-521 to adhere to hES-RPE cells was *** increasing coating concentration,an increasing number of cells attached to the surface of LN-521-coated *** contrast,VTN-N presented a strong adhesive ability even at a low *** optimal concentration of LN-521 and VTN-N required to coat and adhesion to hES-RPE cells were 2 and 0.25μg/cm^(2),***,both LN-521 and VTN-N could facilitate adoption of the desired cobblestone cellular morphology with tight junction and showed polarity by the hES-RPE ***,hES-RPE cells cultivated in VTN-N had a greater phagocytic ability,and it took less time for these hES-RPE cells to ***:VTN-N is a more suitable coating substrate for cultivating hES-RPE cells.

关键词： retinal pigment epithelial stem cell surface coating laminin vitronectin cell adhesion phagocytosis

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Inhibition of Escherichia coli nitroreductase by the constituents in Syzygium aromaticum

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Chinese Journal of Natural Medicines 2022年第7期20卷 506-517页

作者： CHEN Lu CHEN Xi bai yue ZHAO Zi-Nan CAO Yun-Feng LIU Li-Kun JIANG Tao HOU Jie College of Basic Medical Sciences Dalian Medical UniversityDalian 116044China Dalian Runsheng Kangtai Medical Laboratory Co. Ltd.Dalian 116000China

Gut bacterial nitroreductases play an important role in reduction of various nitroaromatic compounds to the corresponding N-nitroso compounds,hydroxylamines or aromatic amines,most of which are carcinogenic and mutagenic *** of gut nitroreductases has been recognized as an attractive approach for reducing mutagen metabolites in the colon,so as to prevent colon *** this study,the inhibitory effects of 55 herbal medicines against Escherichia coli(***)nitroreductase(EcNfsA)were *** with other herbal extracts,Syzygium aromaticum extract showed superior inhibitory potency toward EcNf-sA mediated nitrofurazone ***,the inhibitory effects of 22 major constituents in Syzygium aromaticum against EcNfsA were *** with other tested natural compounds,ellagic acid,corilagin,betulinic acid,oleanic acid,ursolic acid,urolith-in M5 and isorhamnetin were found with strong to moderate inhibitory effect against EcNfsA,with IC50 values ranging from 0.67 to 28.98 mol·L^(−1).Furthermore,the inhibition kinetic analysis and docking simulation demonstrated that ellagic acid and betulinic acid potently inhibited EcNfsA(Ki<2μmol·L−1)in a competitively inhibitory manner,which created strong interactions with the catalytic triad of *** summary,our findings provide new scientific basis for explaining the anti-mutagenic activity of Syzygium aromaticum,where some newly identified EcNfsA inhibitors can be used for developing novel agents to reduce the toxicity induced by bacteri-al nitroreductase.

关键词： Gut bacterial nitroreductase EcNfsA inhibitor Syzygium aromaticum Anti-mutagenic activity

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电化学沉积Nd掺杂ZnO薄膜的结构和光学性质的研究（英文）

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稀有金属材料与工程 2016年第6期45卷 1419-1422页

作者：曹萍白越长春工程学院吉林长春130012 中国科学院长春光学精密机械与物理研究所吉林长春130033

用电化学沉积方法制备出了Nd掺杂的ZnO薄膜,并研究其结构和光学性质。X射线衍射谱的结果表明Nd^(3+)替代Zn2+进入到ZnO晶格中,并没有引起杂相的出现。吸收谱的分析表明,随着掺杂浓度的增大,吸收峰向短波长方向移动,即发生蓝移。光致发... 详细信息

用电化学沉积方法制备出了Nd掺杂的ZnO薄膜,并研究其结构和光学性质。X射线衍射谱的结果表明Nd^(3+)替代Zn2+进入到ZnO晶格中,并没有引起杂相的出现。吸收谱的分析表明,随着掺杂浓度的增大,吸收峰向短波长方向移动,即发生蓝移。光致发光谱的结果表明随着Nd^(3+)掺杂浓度的增大,紫外峰强度减小,可见光部分强度增大了。

关键词：钕掺杂氧化锌光学吸收光致发光

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Dexamethasone-induced adipogenesis in primary marrow stromal cell cultures: mechanism of steroid-induced osteonecrosis

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Chinese Medical Journal 2006年第7期119卷 581-588页

作者： YIN Li LI yue-bai WANG Yi-sheng Department of Orthopedics First Affiliated Hospital of ZhengzhouUniversity Zhengzhou 450052 China Department of Biochemistry Medical College of ZhengzhouUniversity Zhengzhou 450052 China

Background In steroid-induced osteonecrosis, hypertrophy and hyperplasia of marrow fat cells and lipid deposition of osteocytes can be found in the femoral head. However, the precise reason is not clear yet. The aim of this study was to observe the effect of dexamethasone （Dex） on differentiation of marrow stromal cells （MSCs）, and to investigate the pathobiological mechanism of steroid-induced osteonecrosis.Methods MSCs in cultures were treated with increasing concentrations of Dex （0, 10^-9, 10^-8, 10^-7, and 10^-6 mol/L） continuously for 21 days. The cells, which were exposed to 0 mol/L （control） or 10^-7 mol/L Dex for 4-21 days, were then cultured for 21 days without Dex. MSCs were stained with Sudan Ⅲ. Number of adipocytes was counted under a light microscope. The activity of alkaline phosphatase （ALP） of MSCs treated with 0, 10^-8, 10-7, and 10^-6 mol/L Dex for 12 days, and that treated with 0 mol/L and 10^-7 mol/L Dex for 8, 10, or 12 days were determined. The levels of triglycerides, osteocalcin and cell proliferation of MSCs treated with 0 mol/L and 10^-7 mol/L Dex were detected. The mRNA expression levels of adipose-specific 422（aP2） gene and osteogenic gene type I collagen in MSCs treated with 0 mol/L and 10^-7 mol/L Dex for 6 days were analyzed by whole-cell dot-blot hybridization. Statistical analysis was performed using Student＇s t test and analysis of variance. P values less than 0.05 were considered significant statistically.Results The number of adipocytes in cultures increased with the duration of MSCs＇ exposure to Dex and the concentration of Dex. The level of ALP activity in the MSCs decreased with concentration of Dex. In the control group, it was 8.69 times of that in the 10^-7 mol/L Dex group on day 12 （t=20.51, P〈0.001）. The level of triglycerides in 10^-7 mol/L Dex group was 3.40 times of that in the control （t=11.00, P〈0.001）. The levels of cell proliferation and osteocalcin in the control were 1.54 and 2.42 times of that in the 10^-7 m

关键词： Dexamethasone bone marrow adipocytes osteonecrosis

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Private Hospitals in Shandong Province：development situation and recommended measures

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中国组织工程研究 2016年第B5期20卷 182-184页

作者： An bai-yue Hou Tian-tian Cui Lin-xing Miao Zhi-min the Medical College of Qingdao University Qingdao 266003 Shandong Province China Qilu Hospital of Shandong University (Qingdao) Qingdao 266003 Shandong Province China The Health Supervision and Law Enforcement Bureau of Guangrao Dongying 257300 Shandong Province China the Affiliated Hospital of Qingdao University Qingdao 266003 Shandong Province China)

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