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Dynamics and adaptive control of a dual-arm space robot with closed-loop constraints and uncertain inertial parameters

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Acta Mechanica Sinica 2014年第1期30卷 112-124页

作者： ying-hong jia Quan Hu Shi-Jie Xu School of Astronautics Beihang University

A dynamics-based adaptive control approach is proposed for a planar dual-arm space robot in the presence of closed-loop constraints and uncertain inertial parameters of the payload. The controller is capable of controlling the po- sition and attitude of both the satellite base and the payload grasped by the manipulator end effectors. The equations of motion in reduced-order form for the constrained system are derived by incorporating the constraint equations in terms of accelerations into Kane＇s equations of the unconstrained system. Model analysis shows that the resulting equations perfectly meet the requirement of adaptive controller design. Consequently, by using an indirect approach, an adaptive control scheme is proposed to accomplish position/attitude trajectory tracking control with the uncertain parameters be- ing estimated on-line. The actuator redundancy due to the closed-loop constraints is utilized to minimize a weighted norm of the joint torques. Global asymptotic stability is proven by using Lyapunov＇s method, and simulation results are also presented to demonstrate the effectiveness of the proposed approach.

关键词： Space robot Dynamics. Adaptive control Closed-loop constraint Parameter uncertainty - Kane's equation

Dynamics of a spacecraft with large flexible appendage constrained by multi-strut passive damper

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Acta Mechanica Sinica 2013年第2期29卷 294-308页

作者： ying-hong jia Shi-Jie Xu Quan Hu School of Astronautics Beihang University

This paper is concerned with the dynamics of a spacecraft with multi-strut passive damper for large flexible *** damper platform is connected to the spacecraft by a spheric hinge,multiple damping struts and a rigid *** damping struts provide damping forces while the rigid strut produces a motion constraint of the multibody *** exact nonlinear dynamical equations in reducedorder form are firstly derived by using Kane＇s equation in matrix *** on the assumptions of small velocity and small displacement,the nonlinear equations are reduced to a set of linear second-order differential equations in terms of independent generalized displacements with constant stiffness matrix and damping matrix related to the damping strut *** simulation results demonstrate the damping effectiveness of the damper for both the motion of the spacecraft and the vibration of the flexible appendage,and verify the accuracy of the linear equations against the exact nonlinear ones.

关键词： Dynamics·Motion constraints·Multi-strut passive damper·Kane's equation

Roll Subsectional Cooling Adaptive Fuzzy Control Based on Fuzzy Model Inversion

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Journal of Iron and Steel Research International 2010年第4期17卷 39-44页

作者： SHAN Xiu-ying LIU hong-min jia Chun-yu Engineering Research Center of Rolling Equipment and Complete Technology of Ministry of Education State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 Hebei China

Flatness is an important equality indicator of strip rolling and roll subsectional cooling is an important method for flatness control, especially for high order flatness component control. It is very hard to build the mathematic model of roll subsectional cooling because of its characteristics of nonlinearity, hysteresis quality and strong coupling, etc. In order to improve the control effect of roll subsectional cooling control model, the roll subsectional cooling adaptive fuzzy control model based on fuzzy model inversion is built according to the separation principle of fuzzy form on the basis of the conventional fuzzy control model, where the parameters of the fuzzy controller can be dynamically regulated according to the change of rolling conditions. Simulation experiment results of the model indicate that the proposed roll subsectional cooling adaptive fuzzy control model based on fuzzy model inversion has high control precision and rapid response speed with strong self-learning and anti-interference capacity and a new method is provided for high precision flatness control.

关键词： fuzzy identification subsectional cooling adaptive fuzzy control flatness control

Controllability of an underactuated spacecraft with one thruster under disturbance

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Acta Mechanica Sinica 2012年第3期28卷 838-847页

作者： Dong-Xia Wang ying-hong jia Lei Jin Hai-Chao Gui Shi-Jie Xu Department of Guidance Navigation and ControlSchool of AstronauticsBeihang University100191 BeijingChina

For an underactuated spacecraft using only one thruster, the attitude controllability with respect to the or- bit frame is studied in the presence of periodical oscillation disturbance, which provides a preconditional guide on de- signing control law for underactuated attitude control sys- tem. Firstly, attitude dynamic model was established for an underactuated spacecraft, and attitude motion was described using the special orthogonal group （SO （3））. Secondly, Liou- ville theorem was used to confirm that the flow generated by the drift vector of the underactuated attitude control system is volume-preserving. Furthermore, according to Poincar6＇s re- currence theorem, we draw conclusions that this drift field is weakly positively poisson stable （WPPS）. Thirdly, the suffi- cient and necessary condition of controllability was obtained on the basis of lie algebra rank condition （LARC）. Finally, the controllable conditions were analyzed and simulated in different cases of inertia matrix with the installed position of thruster.

关键词： Underactuated spacecraft Periodical oscilla-tion disturbance. Controllability. Weakly positively poissonstable ~ Lie algebra

Three-dimensional topological insulators:case of quaternary Heusler compounds

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Rare Metals 2021年第5期40卷 1219-1223页

作者： Xiao-Tian Wang Xue-Fang Dai hong-ying jia Li-ying Wang Guo-Dong Liu Xi-Feng Liu Wen Yuan Yu-Ting Cui School of Material Sciences and Engineering Hebei University of TechnologyTianjin 300130China College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082China Department of Chemistry Michigan State UniversityEast LansingMichigan 48824USA School of Physics and Electronic Engineering Chongqing Normal UniversityChongqing 400044China

The feasibility of converting quaternary Heusler compounds XX’MZ(X=Sc,La;X’=Sc,Y;M=Ru,Fe;Z=Pb)into three-dimensional topological insulators was investigated by first-principle *** is found that the topological insulating state can be achieved in these quaternary Heusler compounds by the proper strain engineering or the substitution of *** of these compounds investigated in this paper have a negative formation energy,which implies that they are possible to be synthesized in reality.

关键词： Topological insulator Heusler compound Electronic structure

基于Optima的实时在线交通流预测方法研究

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交通运输系统工程与信息 2017年第2期17卷 119-125页

作者：李颖宏潘佳琪北方工业大学城市道路交通智能控制技术北京市重点实验室北京100144

目前城市道路交通流预测主要是基于物理模型、数理统计特性并融合部分智能预测算法来实现的,而对于一些影响预测效果的重要交通因素,诸如FIFO原则、交通信号控制方案等在现有的预测方法因无法很好地引入和描述而忽略.本文提出了一种基于... 详细信息

目前城市道路交通流预测主要是基于物理模型、数理统计特性并融合部分智能预测算法来实现的,而对于一些影响预测效果的重要交通因素,诸如FIFO原则、交通信号控制方案等在现有的预测方法因无法很好地引入和描述而忽略.本文提出了一种基于Optima系统实现的实时在线交通预测方法,通过建立路网模型、需求模型及初始OD矩阵获取路网实时状况,并通过构建关联数据库实现实时路网模型信息、交通信号控制信息的有效对接,依据TRE算法预测路段进出口的累积流量并结合模型分配值、历史数据实现实时在线交通预测.以北京市望京区域为例进行仿真验证,通过误差分析,获得了较为理想的预测效果,验证了该预测方案的有效性.

关键词：智能交通交通流预测交通波 Optima系统实时在线

HLA association with mesangial Proliferative Glomerulonephritis in Eastern China

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HLA association with mesangial Proliferative Glomerulonephri...

Outcomes of loco-regional therapy for down-staging of hepatocellular carcinoma prior to liver transplantation

2012年浙江省医学微生物与免疫学及医学病毒学学术年会暨革兰阴性菌感染论坛

作者： Jing-Jie Zhao Jun-Li Liu Ling Liu hong-ying jia hong-Wei Wang Clinical Molecular Biology Laboratory The Second Hospital of Shandong University Department of urology The Second Hospital of Shandong University

Objectives To investigate the association of Human Leukocyte Antigen(HLA) gene with mesangialproliferativeglomerul onephritis(MsPGN)inEastern China Subjects and Methods This study included 1073 patients w sedby clinicians according to clinical manifestations and pathological results and randomly select the same number of healthy cont rols from7418 healthy volunteers recruited inHemato poietic Stem Cell Bank of Shandong,Eastern *** clinical and pathological data of the patients were collected and *** of HLA-A,HLA-B,HLA-DRB1all eles were detected and genefrequencies(GF) and odds ratio(OR)were analyzed. Results The frequencies of alleles HLA-A*23,A*25,B*15,B*40,B*53 and DRBl*18 were signific antly higher in MsPG Npatients compared with normal controls,the frequencies of haplotypesA*23-B*44-DRBl*18,A*25-B*15- DRB1*07,A*03-B*70-DRB1*11,A*68-B*13-DRB1*04,A*11-B*10-DRB1*12 were signific antly increased in MsPGN patients compared with normal *** the otherh and,our results showed that the patients with Kidney failure granule get wor seprognos is than those with out Kidney failure. Conclusions Polymorphism of HLAgenesis associated with the here ditary suscep tibility to *** might be corres ponding susceptive and protective genes associated with MsPGN.

关键词： Glomerulonephritis MsPGN HLA Genefrequenc

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Hepatobiliary & Pancreatic Diseases International 2011年第2期10卷 143-150页

作者： Xian-Jie Shi, Xin Jin, Mao-Qiang Wang, Li-Xin Wei, Hui-Yi Ye, Yu-Rong Liang, ying Luo and jia-hong DongDepartment of Hepatobiliary Surgery Department of Intervention Radiology Department of Pathology and Department of Radiology General Hospital of PLA, Beijing 100853, China [a] Department of Hepatobiliary Surgery General Hospital of PLA Beijing 100853 China [b] Department of Intervention Radiology General Hospital of PLA Beijing 100853 China [c] Department of Pathology General Hospital of PLA Beijing 100853 China [d] Department of Radiology General Hospital of PLA Beijing 100853 China

BACKGROUND: The number of loco-regional therapies (LRTs) for hepatocellular carcinoma (HCC) has increased dramatically during the past decade. Many patients with HCC who were beyond the Milan criteria were allowed to receive a liver transplantation (LT) once the HCC was successfully down-staged. This retrospective study aimed to analyze the outcomes of LRTs prior to LT in patients with HCC beyond the Milan criteria. METHODS: We analyzed 56 patients treated from June 2006 to March 2010: 22 met the Milan criteria (T1+T2, 39.3%), 16 had T3 tumors (28.6%), and 11 had T4a tumors (19.6%), while 7 were suspected of tumor vascular invasion (T4b, 12.5%). All patients underwent preoperative LRTs, including transcatheter arterial chemoembolization, radiofrequency ablation, percutaneous ethanol injection, liver resection, and/or microwave coagulation therapy. The number of the patients who were successfully down-staged before LT, the types of LRTs used before LT, and their outcomes after LT were recorded. RESULTS: Eleven patients had necrotic tumors (pT0, 19.6%); 6 had pT1 tumors (10.7%), 22 had pT2 tumors (39.3%), 6 had pT3 tumors (10.7%), 5 had pT4a tumors (8.9%), and 6 had pT4b tumors (10.7%). The histopathologic tumors of 39 patients (69.6%) were down-staged and met the established Milan criteria (pT0-2). Imaging-proven under-staging was present in 5 HCC patients (8.9%) who had tumors involving the intrahepatic venous system. Twenty-three patients (41.1%) had stable HCC and 10 (17.9%) died. The 1-, 3- and 4-year survival rates were 96%, 73% and 61%, respectively, with a mean survival time of 22.29±1.63 months. Six patients died of tumorrecurrence. The 1-, 3- and 4-year recurrence-free survival (RFS) rates were 88%, 75% and 66%, respectively. The 3-year RFS of patients with pT0-2 tumors was 82%, which was markedly greater than that of patients with pT3 tumors (63%, P=0.018) or pT4 tumors (17%, P=0.000). Although the 3-year RFS of patients with pT3 tumors was greater than tha

关键词： hepatocellular carcinoma tumor down-staging loco-regional therapy liver transplantation

Microglia lactylation in relation to central nervous system diseases

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Neural Regeneration Research 2025年第1期20卷 29-40页

作者： Hui Yang Nan Mo Le Tong jianhong Dong Ziwei Fan Mengxian jia Juanqing Yue ying Wang School of Pharmacy Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Clinical Laboratory The Fourth Clinical Medical College of Zhejiang University of Traditional Chinese Medicine(Hangzhou First People’s Hospital)HangzhouZhejiang ProvinceChina College of Medical Veterinary and Life SciencesUniversity of GlasgowGlasgowUK Department of Orthopedics(Spine Surgery) the First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina Department of Pathology Affiliated Hangzhou First People’s HospitalWestlake University School of MedicineHangzhouZhejiang ProvinceChina Department of Clinical Research Center Affiliated Hangzhou First People’s HospitalWestlake University School of MedicineHangzhouZhejiang ProvinceChina

The development of neurodegenerative diseases is closely related to the disruption of central nervous system ***,as innate immune cells,play important roles in the maintenance of central nervous system homeostasis,injury response,and neurodegenerative *** has been considered a metabolic waste product,but recent studies are revealing ever more of the physiological functions of *** is an important pathway in lactate function and is involved in glycolysis-related functions,macrophage polarization,neuromodulation,and angiogenesis and has also been implicated in the development of various *** review provides an overview of the lactate metabolic and homeostatic regulatory processes involved in microglia lactylation,histone versus non-histone lactylation,and therapeutic approaches targeting ***,we summarize the current research on microglia lactylation in central nervous system diseases.A deeper understanding of the metabolic regulatory mechanisms of microglia lactylation will provide more options for the treatment of central nervous system diseases.

关键词： brain central nervous system glycolysis immune response inflammation lactate metabolism lactate lactylation microglia neurodegenerative diseases