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Dynamic modeling and RBF neural network compensation control for space flexible manipulator with an underactuated hand

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Chinese journal of Aeronautics 2024年第3期37卷 417-439页

作者： Dongyang shang Xiaopeng LI Meng YIN Fanjie LI school of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

In space operation,flexible manipulators and gripper mechanisms have been widely used because of light weight and ***,the vibration caused by slender structures in manipulators and the parameter perturbation caused by the uncertainty derived from grasping mass variation cannot be *** existence of vibration and parameter perturbation makes the rotation control of flexible manipulators difficult,which seriously affects the operation accuracy of ***’s more,the complex dynamic coupling brings great challenges to the dynamics modeling and vibration *** solve this problem,this paper takes the space flexible manipulator with an underactuated hand(sFMUH)as the research *** dynamics model considering flexibility,multiple nonlinear elements and disturbance torque is established by the assumed modal method(AMM)and Hamilton’s principle.A dynamic modeling simplification method is proposed by analyzing the nonlinear ***’s more,a sliding mode control(sMC)method combined with the radial basis function(RBF)neural network compensation is ***,the control law is designed using a saturation function in the control method to weaken the chatter *** the help of neural networks to identify the uncertainty composition in the sFMUH,the tracking accuracy is *** results of ground control experiments verify the advantages of the control method for vibration suppression of the sFMUH.

关键词： space flexible manipulator RBF neural network Underactuated hand Dynamic models Model simplification

Engineering Plant Cytochrome P450s for Enhanced synthesis of Natural Products: Past Achievements and Future Perspectives

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Plant Communications 2020年第1期1卷 57-63页

作者： Yi shang sanwen Huang Key Laboratory for Potato Biology of Yunnan Province The CAAS-YNNU-YINMORE Joint Academy of Potato ScienceYunnan Normal UniversityKunmingChina Lingnan Guangdong Laboratory of Modern Agriculture Genome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenChina

Cytochrome P450s(P450s)are the most versatile catalysts and are widely used by plants to synthesize a vast array of structurally diverse specialized metabolites that not only play essential ecological roles but also constitute a valuable resource for the development of new *** accelerate the metabolic engineering of these high-value metabolites,it is imperative to identify and characterize pathway P450s,and to further improve their activities through protein *** this review,we focus on P450 engineering and summarize the major strategies for enhancing the stability and activity of P450s and successful cases of P450 *** in which the functions of P450s were altered to create de novo metabolic pathways or novel compounds are discussed as *** also overview emerging tools,specifically DNA synthesis,machine learning,and de novo protein design,as well as the evolutionary patterns of P450s unveiled from a massive number of DNA sequences that could be integrated to accelerate the engineering of these *** approaches would greatly aid in the exploitation of plant-specialized metabolites or derivatives for various uses including medical applications.

关键词： plant cytochrome P450 plant natural product protein engineering amino acid co-evolution protein design

A path planning algorithm based on Bezier curves for underwater vehicles

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High Technology Letters 2010年第3期16卷 293-298页

作者： shang Liuji Wang shuo Laborary of Complex systems and Intelligence sciences Institute of Automation Chinese Academy of Sciences Beijing 100190 P.R. China

An on-line path planning algorithm based on Bezier curves is presented for underwater vehicles. Aiming at the special requirements of underwater vehicles and 3D enviromnent, the algorithm consists of two steps ： the generation of spatial path and the processing of some constraints. A path for underwater vehicles is planned, which satisfies the velocity constraint and the centripetal acceleration constraint of underwater vehicles. The proposed path planning method can be used for the vehicle＇ s locomotion and navigation control.

关键词： path planning Bezier curves underwater vehicles

A 3D-QsAR study of HIV-1 Integrase Inhibitors Using RAsMs and Topomer CoMFA

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Chinese journal of structural Chemistry 2019年第6期38卷 867-881页

作者： TONG jian-Bo QIN shang-shang LEI shan WANG Yang shaanxi Key Laboratory of Chemical Additives for Industry Shaanxi University of Science and Technology

Acquired Immunodeficiency syndrome(AIDs) is a significant human health threat around the world. Therefore, the study of anti-human immunodeficiency virus(HIV) drug design has become an important task for today’s society. In this paper, a three-dimensional quantitative structure-activity relationships study(3 D-QsAR) was conducted on 53 HIV-1 integrase inhibitors(IN) using random sampling analysis on molecular surface(RAsMs) and Topomer comparative molecular field analysis(Topomer CoMFA). The multiple correlation coefficients of fitting, cross-validation, and external validation of two models were 0.926, 0.815 and 0.908 and 0.930, 0.726 and 0.855, respectively. The results indicated that two models obtained had both favorable estimation stability and good prediction capability. Topomer search was used to search appropriate R groups from ZINC database, and 28 new compounds were designed thereby. The Topomer CoMFA model was subsequently used to predict the biological activity of these compounds, showing that 24 of the new compounds were more active than the template molecule. Ligands of the template molecule and new designed compounds were used for molecular docking to study the interaction of these compounds with the protein receptor. The results show that the ligands would form hydrogen-bonding interactions with the residues LEU58, THR83, GLN62, MET155, LYs119 and ALA154 of the protein receptor generally, thereby providing additional insights for the design of even more effective HIV/AIDs drugs.

关键词： 3D-QsAR integrase inhibitors RAsMs Topomer CoMFA molecular docking

INTEGRABLE DIsCRETIsATION OF THE LOTKA-VOLTERRA sYsTEM

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journal of Computational Mathematics 2015年第5期33卷 468-494页

作者： Yang He Yajuan sun Zaijiu shang Department of Modern Physics and Collaborative Innovation Center for Advanced Fusion Energy and Plasma sciences University of Science and Technology of China Hefei Anhui 230026 China Key Laboratory of Geospace Environment Chinese Academy of Sciences University of Science and Technology of China Hefei Anhui 230026 China LsEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China Academy of Mathematics and systems science Chinese Academy of Sciences Beijing 100190 China

In this paper, we apply Hirota＇s discretisation to a three-dimensional integrable Lotka- Volterra system. By analyzing the three-dimensional modified equation of the resulting numerical method, we show that it is volume-preserving, and has two independent first integrals. Moreover, it can be formally reduced to a system in one dimension via a volume- preserving transformation. If the given initial value is located in the positive octant, we prove that the numerical solution is confined to a one-dimensional connected and compact space which is diffeomorphic to a circle.

关键词： Integrable Lotka-Volterra system Hirota's integrable discretisation Backwarderror analysis Modified differential equation.

Color cyclic homology and steinberg Lie color algebras

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Frontiers of Mathematics in China 2015年第5期10卷 1179-1202页

作者： Yongjie WANG shikui shang Yun GAO school of Mathematical sciences University of Science and Technology of China Hefei 230026 China Department of Mathematics and statistics York University Toronto Ontario M3J 1P3 Canada

The present paper contains two interrelated developments. First, the basic properties of the construction theory over the steinberg Lie color algebras are developed in analogy with steinberg Lie algebra case. This is done on the example of the central closed of the steinberg Lie color algebras. The second development is that we define the first ε-cyclic homology group HC1 （R, ε） of the F-graded associative algebra R （which could be seemed as the generalization of cyclic homology group and the Z/2Z-graded version of cyclic homology that was introduced by Kassel） to calculate the universal central extension of steinberg Lie color algebras.

关键词： steinberg Lie color algebra ε-cyclic homology group universalcentral extension

Role of Notch signaling in regulating innate immunity and inflammation in health and disease

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Protein & Cell 2016年第3期7卷 159-174页

作者： Yingli shang sinead smith Xiaoyu Hu school of Medicine and Institute for Immunology Tsinghua University Beijing 100084 China Department of Clinical Medicine Trinity College Dublin Dublin 2 Ireland

The Notch signaling pathway is conserved from Drosophila to mammals and is critically involved in developmental processes. In the immune system, it has been established that Notch signaling regulates multiple steps of T and B cell development in both central and peripheral lymphoid organs. Relative to the well documented role of Notch signaling in lymphocyte development, less is known about its role in regulating myeloid lineage development and function, especially in the context of acute and chronic inflammation. In this review article, we will describe the evidence accumulated during the recent years to support a key regulatory role of the Notch pathway in innate immune and inflammatory responses and discuss the potential implications of such regulation for pathogenesis and therapy of inflammatory disorders.

关键词： inflammation innate immunity macrophages Notch signaling RBP-j

智能网联环境下混合交通流仿真设计与特性分析

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山东理工大学学报（自然科学版） 2025年第2期39卷 44-49页

作者：张文雪商强山东理工大学交通与车辆工程学院山东淄博255049

以智能网联环境下混合交通流的特性为研究对象,在sUMO仿真软件中设置高速公路双向六车道的交通环境,利用sUMO仿真软件和Python软件对模拟智能网联汽车的CACC(cooperative adaptive cruise control)模型和模拟人工驾驶汽车的IDM(intellig... 详细信息

以智能网联环境下混合交通流的特性为研究对象,在sUMO仿真软件中设置高速公路双向六车道的交通环境,利用sUMO仿真软件和Python软件对模拟智能网联汽车的CACC(cooperative adaptive cruise control)模型和模拟人工驾驶汽车的IDM(intelligent driver model)模型进行仿真实验,并对CACC汽车不同渗透率下的数据进行对比分析,从而对智能网联汽车与人工驾驶汽车形成的混合交通流模型进行研究。模拟仿真结果表明:在不同渗透率的智能网联汽车和人工驾驶汽车的混合交通流中,随着CACC汽车渗透率的不断增加,道路的流率不断提高,平均速度也不断提高;当CACC汽车渗透率达到100%时,道路的总时间延误可以减少约862 s;随着CACC汽车渗透率的不断增加,道路上车辆的换道频率也随之下降,减少了道路上车辆之间的速度差。智能网联汽车的参与可以提高高速公路的通行能力和车道的利用率,提高车辆的平均速度并减少行程的时间延误。

关键词：智能网联汽车混合交通流仿真混合交通流特性 CACC和IDM模型

A practical nonlinear robust control approach of electro-hydraulic load simulator

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Chinese journal of Aeronautics 2014年第3期27卷 735-744页

作者： Wang Chengwen jiao Zongxia Wu shuai shang Yaoxing school of Automation science and Electrical Engineering Science and Technology on Aircraft Control Laboratory

This paper studies a nonlinear robust control algorithm of the electro-hydraulic load simulator （EHLs）. The tracking performance of the EHLs is mainly limited by the actuator＇s motion disturbance, flow nonlinearity, and friction, etc. The developed controller is developed based on the nonlinear motion loading model. The problems of the actuator＇s disturbance and flow nonlinearity are considered. To address the friction problem, the friction model of the loading motor is identified experimentally. The friction disturbance is compensated using the obtained friction model. Therefore, this paper considers the main three factors comprehensively. The developed algorithm is easy to apply since the controller can be obtained just with one step back-stepping design. The stability of the developed algorithm is proven via Lyapunov analysis. Both co-simulation and experiments are performed to verify the effectiveness of this method.

关键词： Co-simulation Electro-hydraulic load simulator Hydraulic control equipment Nonlinear robust control Parametric uncertainty