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Precise robust motion control of cell puncture mechanism driven by piezoelectric actuators with fractional-order nonsingular terminal slidingmode control

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Bio-Design and Manufacturing 2020年第4期3卷 410-426页

作者： Shengdong Yu hongtao wu Mingyang Xie Haiping Lin Jinyu Ma Wenzhou Polytechnic Wenzhou 325000China Nanjing University of Aeronautics and Astronautics Nanjing 210016China Hangzhou Vocational and Technical College Hangzhou 310000China

A novel robust controller is proposed in this study to realize the precise motion control of a cell puncture mechanism(CPM)driven by piezoelectric ceramics(PEAs).The entire dynamic model of CPM is constructed based on the Bouc–Wen model,and the nonlinear part of the dynamic model is optimized locally to facilitate the construction of a robust controller.A model-based,nonlinear robust controller is constructed using time-delay estimation(TDE)and fractional-order nonsingular terminal sliding mode(FONTSM).The proposed controller does not require prior knowledge of unknown disturbances due to its real-time online estimation and compensation of unknown terms by using the TDE *** controller also has finite-time convergence and high-precision trajectory tracking capabilities due to FONTSM manifold and fast terminal sliding mode-type reaching *** stability of the closed-loop system is proved by Lyapunov stability *** simulation and hardware-in-loop simulation experiments of CPM verify that the proposed controller outperforms traditional terminal sliding mode controllers,such as the integer-order or model-free *** proposed controller can also continuously output without chattering and has high control *** embryo is used as a verification target to complete the cell puncture *** the engineering application perspective,the proposed control strategy can be effectively applied in a PEA-driven CPM.

关键词： Cell puncture mechanism(CPM) Piezoelectric actuator(PEA) Robust motion control Fractional-order nonsingular terminal sliding mode(FONTSM) Time-delay estimation(TDE)

A novel method for singularity analysis of the 6-SPS parallel mechanisms

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Science China(Technological Sciences) 2011年第5期54卷 1220-1227页

作者： CHENG ShiLi wu hongtao WANG ChaoQun YAO Yu ZHU JianYing College of Mechanical & Electrical Engineering Nanjing University of Aeronautics & Astronautics Nanjing 210016 China College of Engineering Nanjing Agricultural University Nanjing 210031 China College of Aerospace Engineering Nanjing University of Aeronautics & Astronautics Nanjing 210016 China

Singularity analysis is a basic problem of parallel mechanism, and this problem cannot be avoided in both workspace and motion planning. How to express the singularity locus in an analytical form is the research emphasis for many researchers for a long time. This paper presents a new method for the singularity analysis of the 6-SPS parallel mechanism. The rotation matrix is described by quaternion, and both the rotation matrix and the coordinate vectors have been expanded to four-dimensional forms. Through analyzing the coupling relationship between the position variables and the orientation variables, utilizing properties of the quaternion, eight equivalent equations can be obtained. A new kind of Jacobian matrix is derived from those equations, and the analytical expression of the singularity locus is obtained by calculating the determinant of the new Jacobian matrix. The singularity analysis of parallel mechanisms, whose moving platform actuated by 6 links and the vertices of both the base and the moving platforms has been placed on a circle respectively, can be solved by this analytical expression.

关键词： parallel mechanism singularity analysis quaternion Jacobian matrix

The effect of dolomite amendment on soil organic carbon mineralization is determined by the dolomite size

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Ecological Processes 2021年第1期10卷 118-129页

作者： hongtao wu Jinli Hu Muhammad Shaaban Peng Xu Jinsong Zhao Ronggui Hu College of Urban and Environmental Sciences Hubei Normal UniversityHuangshiChina College of Resources and Environment Huazhong Agricultural UniversityWuhanChina Department of Soil Science Faculty of Agricultural Sciences and TechnologyBahauddin Zakariya UniversityMultanPakistan.

Background:The size of lime material is vital for the efficiency of ameliorating soil acidity,thereby influencing soil biochemical ***,the effects of different sized lime material application on soil organic carbon(SOC)mineralization are yet to be ***,a 35-day incubation experiment was conducted to determine the effects of three particle size fractions(0.5 to 0.25,0.25 to 0.15,and<0.15 mm)of dolomite on SOC mineralization of two acidic paddy ***:CO_(2) emission was increased by 3–7%,11–21%,and 32–49%for coarse-,medium-,and fine-sized dolomite treatments,respectively,compared to the control in both *** also well conformed to a first-order model in all treatments,and the estimated decomposition rate constant was significantly higher in the fine-sized treatment than that of other treatments(P<0.05),indicating that SOC turnover rate was dependent on the dolomite *** finer particle sizes were characterized with higher efficiencies of modifying soil pH,consequently resulting in higher dissolved organic carbon contents and microbial biomass carbon,eventually leading to higher CO_(2) ***:The results demonstrate that the size of dolomite is a key factor in regulating SOC mineralization in acidic paddy soils when dolomite is applied to manipulate soil pH.

关键词： Dolomite Particle size SOC mineralization Acidic paddy soil

Expression of co-stimulatory molecules B7-2 and PD-L1 on peripheral blood mononuclear cells in patients with chronic hepatitis B virus infection

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Journal of Nanjing Medical University 2009年第5期23卷 347-351页

作者： Lingxia Fei Shipin wu hongtao Chen Department of Infectious Disease Shenzhen People's Hospitalthe Second Clinical Medical College of Jinan University Shenzhen 518020 China

Objective： To explore the roles of the expression of the co-stimulatory molecule, B7-2, and the co-inhibitory molecule, PD-L1, on peripheral blood mononuclear cells in the mechanism of immunotolerance in chronic hepatitis B virus infection. Methods： Thirty HBV infected patients in the immunoreactive phase and 20 patients in the immunotolerant phase were enrolled in the study, while 20 healthy volunteers were used as controls. RT- PCR and real-time PCR methods were used to detect the expression levels of B7-2 and PD-L1 mRNA in peripheral blood mononuclear cells in chronic HBV infected patients. Results： The B7-2 expression in irnrnunoreactive and immunotolerant patients was significantly lower than that in the controls （P all 〈 0.01 ）; B7-2 expression in immunoreactive patients was significantly lower than in immunotolerant patients （P 〈 0.01）. PD-L1 expression in irnmunoreactive patients and immunotolerant patients was significantly higher than that in normal controls （P all 〈 0.01）. The PD-L1/BT-2 ratios in immunoreactive and immunotolerant patients were significantly higher than that of the healthy controls （P all 〈 0.01）; the PD-L1/ B7-2 ratio was significantly higher in the immunoreactive patients than in the immunotolerant patients （P 〈 0.01）. Conclusion： In chronic HBV infection, changes in the expression of co-stimulatory and co-inhibitory molecules imply a protective adjustment against the patient＇ s immune response that may result in increased immunotolerance and persistent HBV infection.

关键词： Co-stimulatory molecule B7-2 PD-L1 Hepatitis B virus

Regulatory potential of soil available carbon,nitrogen,and functional genes on N_(2)O emissions in two upland plantation systems

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Journal of Integrative Agriculture 2024年第8期23卷 2792-2806页

作者： Peng Xu Mengdie Jiang Imran Khan Muhammad Shaaban hongtao wu Barthelemy Harerimana Ronggui Hu Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China College of Resources and Environment Huazhong Agricultural UniversityWuhan 430070China Hubei Collaborative Innovation Centre for Grain Industry College of AgricultureYangtze UniversityJingzhou 434025China College of Agriculture Henan University of Science and TechnologyLuoyang 471000China College of Urban and Environmental Sciences Hubei Normal UniversityHuangshi 435002China University of Chinese Academy of Sciences Beijing 100049China

Dynamic nitrification and denitrification processes are affected by changes in soil redox conditions,and they play a vital role in regulating soil N_(2)O emissions in rice-based *** is imperative to understand the influences of different upland crop planting systems on soil N_(2)O *** this study,we focused on two representative rotation systems in Central China:rapeseed–rice(RR)and wheat–rice(WR).We examined the biotic and abiotic processes underlying the impacts of these upland plantings on soil N_(2)O *** results revealed that during the rapeseed-cultivated seasons in the RR rotation system,the average N_(2)O emissions were 1.24±0.20 and 0.81±0.11 kg N ha^(–1)for the first and second seasons,*** values were comparable to the N_(2)O emissions observed during the first and second wheat-cultivated seasons in the WR rotation system(0.98±0.25 and 0.70±0.04 kg N ha^(–1),respectively).This suggests that upland cultivation has minimal impacts on soil N_(2)O emissions in the two rotation *** positive correlations were found between N_(2)O fluxes and soil ammonium(NH_(4)^(+)),nitrate(NO_(3)^(–)),microbial biomass nitrogen(MBN),and the ratio of soil dissolved organic carbon(DOC)to NO_(3)^(–)in both RR and WR rotation ***,the presence of the AOA-amoA and nirK genes were positively associated with soil N_(2)O fluxes in the RR and WR systems,*** implies that these genes may have different potential roles in facilitating microbial N_(2)O production in various upland plantation *** using a structural equation model,we found that soil moisture,mineral N,MBN,and the AOA-amoA gene accounted for over 50%of the effects on N_(2)O emissions in the RR rotation *** the WR rotation system,soil moisture,mineral N,MBN,and the AOA-amoA and nirK genes had a combined impact of over 70%on N_(2)O *** findings demonstrate the interactive effects of functional genes and soil factors,including

关键词： upland-rice cultivation N_(2)O emission regulatory factors functional genes

A multiphysical-geochemical coupling model for caprock sealing efficiency in CO_(2) geosequestration

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Deep Underground Science and Engineering 2023年第2期2卷 188-203页

作者： Jianguo Wang Huimin Wang Xiaolin Wang Shengqi Yang hongtao wu Chunfai Leung Jiali Tian School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhouChina State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhouChina College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjingChina School of Engineering University of TasmaniaHobartTasmaniaAustralia Center for Offshore Research and Engineering National University of SingaporeSingaporeSingapore

Precipitation or dissolution due to geochemical reactions has been observed in the caprocks for CO_(2) *** reactions modify the caprock sealing efficiency with self-limiting or ***,the effect of this modification on the caprock sealing efficiency has not been fully investigated through multiphysical-geochemical coupling *** this study,a multiphysical-geochemical coupling model was proposed to analyze caprock sealing *** coupling model considered the full couplings of caprock deformation,two-phase flow,CO_(2) concentration diffusion,geochemical reaction,and CO_(2) *** two-phase flow only occurs in the fracture network and the CO_(2) may partially dissolve into water and diffuse through the concentration *** dissolved CO_(2) has geochemical reactions with some critical minerals,thus altering flow *** CO_(2) in the fracture network diffuses into matrix,causing the matrix *** fully coupling model was validated with a penetration experiment on a cement cube and compared with two other models for CO_(2) storage ***,the effects of geochemical reactions on penetration depth and pore pressure were studied through parametric *** numerical simulations reveal that the coupling of geochemical reactions and matrix diffusion significantly affect the caprock sealing *** reactions occur at a short time after the arrival of CO_(2) concentration and modify the fracture *** CO_(2) diffusion into the matrix requires a much longer time and mainly induces matrix *** effects may produce selfenhancement or self-limiting depending on the flow rate in the fracture network,thus significantly modifying caprock sealing efficiency.

关键词： caprock sealing efficiency CO_(2)diffusion CO_(2)geosequestration geochemical reaction sorption strain

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Human-robot interface based on sEMG envelope signal for the collaborative wearable robot

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Biomimetic Intelligence & Robotics 2023年第1期3卷 38-45页

作者： Ziyu Liao Bai Chen Dongming Bai Jiajun Xu Qian Zheng Keming Liu hongtao wu College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Mechanical and Electrical Engineering College of Jinhua Polytechnic Jinhua 321016China Key Laboratory of Crop Harvesting Equipment Technology of Zhejiang Province Jinhua 321016China

Surface electromyography(sEMG)control interface is a common method for human-centered *** have frequently improved the recognition accuracy of sEMG through multichannel or high-precision signal acquisition ***,this increases the cost and complexity of the control ***,this study developed a control interface based on the sEMG enveloped signal for a collaborative wearable robot to improve the accuracy of sEMG recognition based on the time-domain(TD)***,an acquisition device is developed to obtain the sEMG envelope signal,and 11 types of TD features are extracted from the sEMG envelope signal acquired from the upper ***,a dimension reduction method based on the correlation coefficient is proposed,transforming the 11-dimensional feature into a five-dimensional envelope feature set without decreasing the ***,a recognition algorithm based on a neural network has also been proposed for gesture ***,the recognition accuracy of the proposed method,principal component analysis(PCA)feature set,and Hudgins TD feature set is compared,with their accuracy at 84.39%,72.44%,and 70.89%,***,the results indicate that the envelope feature set performs better than the common gesture recognition method based on signal channel sEMG envelope signal.

关键词： Surface electromyography(sEMG) Gesture recognition Features extraction Wearable robot

KINEMATICS AND ERROR ANALYSIS FOR MULTIBODY SYSTEM

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Chinese Journal of Mechanical Engineering 1994年第1期7卷 49-52,62页

作者： wu hongtao Liu Youwu Wang Shuxin Yun Chao Zhang Qing Tianjin University

In this paper, a new concept, i.e. Generalized Jacobian Matrix of MBS (abbreviation for multibody system) is presented which unifies three concepts of different realms, Partial (angular) velocity in MBS, first order effect coefficient in mechanism, Jacobian Matrix in robotics. This new concept not only enriches and developes kinematics of MBS and makes kinematics theory of MBS concise and being a formal way. but also becomes a new way to kinematic analysis of spatial mechanisms. It is also enlarged the paper that the usage of kinematics of MBS, the identical relationship between kinematics of MBS and error analysis of MBS is revealed.

关键词： Kinematics of MBS Error analysis Configuration space

Relationship Between Soil Properties and Different Fractions of Soil Hg

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Pedosphere 2001年第3期11卷 257-262页

作者： wu hongtao YU GUIFEN QING CHANGLE and CHEN TONGBIN Southwest Agricultural University, Chongqing 400716 (China) Institute of Geographic Sciences and Natural Resources, the Chinese Academy of Sciences, Beijing 100101 (China) Institute of Soil Science, th 西南农业大学重庆 400716 中科院南京土壤所江苏南京 210008 中科院地理科学与资源所北京 100101

Correlation and path analysis methods were used to study the relationship between soil properties and the distribution of different soil Hg fractions with nine representative soils from Chongqing, China. Results showed that clay (< 2 m) could increase water-soluble Hg (r = 0.700*). Soil organic matter (OM) could enhance the increase of elemental Hg (r = 0.674*). The higher the base saturation percentage (BSP), the more the residual Hg (T = 0.684*). Organic Hg, the sum of acid-soluble organic Hg and alkali-soluble Hg, was positively affected by silt (2-20 μm) but negatively affected by pH, with the direct path coefficients amounting to 1.0487 and 0.5121, respectively. The positive effect of OM and negative effect of BSP on organic Hg were the most significant, with the direct path coefficients being 0.7614 and -0.8527, respectively. The indirect effect of clay (< 2 μm) via BSP (path coefficient = 0.4186) was the highest, showing that the real influencing factor in the effect of clay (< 2 μm) on acid-soluble organic Hg was BSP. Since the available Hg fraction, water-soluble Hg, was positively affected by soil clay content, and the quite immobile and not bioavailable residual Hg by soil BSP, suitable reduction of clay content and increase of BSP would be of much help to reduce the Hg availability and Hg activity in Hg-contaminated soils.

关键词： different fractions soil Hg soil properties