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GLOBALLY ASYMPTOTICALLY STABLE FORMATION CONTROL OF THREE AGENTS

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Journal of Systems Science & Complexity 2012年第6期25卷 1068-1079页

作者： qin WANG yu-Ping TIAN Yaojin XU School of Automation Southeast University

This paper considers the formatiomshape control of three agents in the plane. By adding an adaptive perturbation to any agent＇s movement direction, a novel control strategy is proposed. It is shown that the proposed novel control law can not only guarantee the global asymptotical stability of the desired formation shape, but also ensure the collision avoidance of agents between each other. Simulation results are provided to illustrate the effectiveness of the control algorithm.

关键词： Formation control global asymptotic stability multi-agents system.

Detecting micro-blog user interest communities through the integration of explicit user relationship and implicit topic relations

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Science China(Information Sciences) 2017年第9期60卷 64-77页

作者： yu qin Zhengtao yu Yanbing WANG Shengxiang GAO Linbin SHI Institute of Information Engineering and Automation Kunming University of Science and Technology Key Laboratory of Intelligent Information Processing Kunming University of Science and Technology

In order to effectively utilize the explicit user relationship and implicit topic relations for the detection of micro-blog user interest communities, a micro-blog user interest community(MUIC) detection approach is proposed. First, through the analysis of the follow relationship between users, we have defined three types of such relationships to construct the user follow-ship network. Second, taking the semantic correlation between user tags into account, we construct the user interest feature vectors based on the concept of feature mapping to build a user tag based interest relationship network. Third, user behaviors, such as reposting, commenting, replying, and receiving comments from others, are able to provide certain guidance for the extraction of micro-blog topics. Hence, we propose to integrate the four mentioned user behaviors that are considered to provide guidance information for the traditional latent Dirichlet allocation(LDA) model. Thereby, in addition to the construction of a topic-based interest relationship network, a guided topic model can be built to extract the topics in which the user is interested. Finally, with the integration of the afore-mentioned three types of relationship network, a micro-blog user interest relationship network can be created. Meanwhile, we propose a MUIC detection algorithm based on the contribution of the neighboring nodes. The experiment result proves the effectiveness of our approach in detecting MUICs.

关键词： feature mapping implicit topic guided topic model contribution of the neighboring nodes

θ-improved limited tolerance relation model of incomplete information system for evaluation of water conservancy project management modernization

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Water Science and Engineering 2013年第4期6卷 469-477页

作者： yu-qin GAO Guo-hua FANG Ya-qin LIU College of Water Conservancy and Hydropower Engineering Hohai University

The modernization of water conservancy project management is a complicated engineering system involving a management system, a management method, management personnel, the exertion of social, economic, and ecological effects, and so on. However, indices for evaluating the modernization of water conservancy project management are usually unobtainable in practical applications. Conducting appropriate extension of the classical rough set theory and then applying it to an incomplete information system are the key to the application of the rough set theory Based on analysis of some extended rough set models in incomplete information systems, a rough set model based on the θ-improved limited tolerance relation is put forward. At the same time, upper approximation and lower approximation are defined under this improved relation. According to the evaluation index system and management practices, the threshold for θ is defined. An example study indicates the practicability and maneuverability of the model.

关键词： Key words: modernization of water conservancy project management O-improved limitedtolerance relation model," upper and lower approximations," threshold

Quantized vortices in spinor Bose–Einstein condensates with time–space modulated interactions and stability analysis

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Chinese Physics B 2020年第10期29卷 227-232页

作者： yu-qin Yao Ji Li Department of Applied Mathematics China Agricultural UniversityBeijing 102206China Department of Physics Taiyuan Normal UniversityTaiyuan 030031China

The three-component Gross–Pitaevskii equation with an angular momentum rotational term can be served as a model to study spinor Bose–Einstein condensates (BECs) with time–space modulated interactions. Vortex solutions of the spinor BECs with spatiotemporally modulated interactions are worked out by similarity transformation. Theoretical analysis and numerical simulation of vortex states are demonstrated. Stable vortex states are obtained by adjusting the frequency of the external potential and the spatiotemporally modulated interaction.

关键词： spinor Bose-Einstein condensates spatiotemporal modulation vortex solution dynamical stability

THEORETICAL INVESTIGATION ON THE DYNAMIC PERFORMANCE OF CMUT FOR DESIGN OPTIMIZATION

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Acta Mechanica Solida Sinica 2013年第1期26卷 99-110页

作者： Ting yu Wenchao Zhou Peng Xu Fengqi yu qin Qian Department of Integrated Electronics Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences The Chinese University of Hong Kong School of Civil Engineering and Mechanics Huazhong University of Sciences and Technology

Although many modeling approaches exist for analyzing the behavior of capacitive micro-machined ultrasonic transducers （CMUTs）, the relation equation between the design pa- rameters with input and output is still lacking. What there is can only be used to analyze the dynamic performance of CMUT indirectly and qualitatively, such as stiffness and sound pressure. A lumped-parameter theoretical model based on the dynamic theory is proposed in this paper. The relation equations between the design parameters with inputs and outputs are given. The results obtained by the proposed model agree well with those by finite element method （FEM） simulation. The dynamic and static behavior of CMUT can be clearly depicted, which is helpful for design and optimization iterations. This shows that the proposed model makes it easier to optimize the parameters of a CMUT with respect to output and bandwidth directly and to better understand the influence of each parameter.

关键词： CMUT dynamic theory finite element method

Effect of Iron on the Stability of Rhodochrosite at the Topmost Lower Mantle Conditions

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Journal of Earth Science 2024年第2期35卷 504-513页

作者： Tianlei Zhai Fei qin Shengxuan Huang Shan qin yu Gong Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationSchool of Earth and Space SciencesPeking UniversityBeijing100871China School of Earth Sciences and Resources China University of GeosciencesBeijing100083China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China

Carbonates are viewed as the principal oxidized carbon carriers during subduction,and thus the stability of subducted carbonates has significant implications for the deep carbon *** we investigate the high pressure-temperature behaviors of rhodochrosite in the presence of iron up to∼34 GPa by in-situ X-ray diffraction and ex-situ Raman *** relatively low temperature below∼1500 K,MnCO_(3)breaks down into MnO and CO_(2).Upon heating to∼1800 K,however,the MnCO_(3)-Fe^(0)reactions occur with the formation of Mn_(3)O_(4),Fe^(O)and reduced carbon.A'three-stage'reaction mechanism is proposed to understand the kinetics of the carbon-iron-manganese redox *** results suggest that Fe^(0)can serve as a reductant to greatly affect the stability of rhodochrosite,which implies that the effect of Fe-metal should be seriously considered for the high pressure-temperature behaviors of other predominant carbonates at Earth's mantle conditions,particularly at depths greater than∼250 km.

关键词： deep carbon cycle rhodochrosite reduced mantle diamond formation high pressure tectonics geochemistry

A Novel Method for Type Synthesis of Parallel Mechanism Without Parasitic Motion Based on 2R1T Parallel Mechanism with Rotational Bifurcation

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 191-202页

作者： Jinghan qin Chunzhan yu Zhibo Sun Lei Cao School of Technology Beijing Forestry UniversityBeijing 100083China Engineering Training Center Beihang UniversityBeijing 102206China Capital Aerospace Machinery Co.Ltd Beijing 100621China

The parasitic motion has been widely recognized as the major drawback of the parallel *** a class of 2R1T PMs(parallel mechanism)without parasitic motion has been ***,these PMs can only rotate around two axes in sequential *** decreases the performance of the balancing adjustment of the *** this paper,a family of 2R1T PMs without parasitic motion was reconstructed by using a novel method based on the remarkable properties of rotational bifurcation mechanisms,which can rotate in sequential ***,some PMs rotating around two continuous axes in an arbitrary order are established by adding single *** the practicability of these structures into consideration,the workspace of 3-PRPS PM was analyzed as an ***,this study explores the practical application of the PMs without parasitic motion in developing balance mechanisms in rough-terrain fre-fghting *** the climbing process,the tank is adjusted to be parallel to the horizontal plane in *** is proved that this kind of structure realizes continuous rotation around two rotation axes on the premise of no parasitic motion.

关键词： Parallel mechanism Rotational bifurcation Parasitic motion Type synthesis Balance mechanism

Study of a smart platform based on backstepping control method

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 599-608页

作者： Li Luyu Cheng Baowei Zhang yu qin Han State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China School of Civil Engineering Dalian University of Technology Dalian 116024 China School of Electronic Engineering Dalian University of Technology Dalian 116024 China

A structural model is significant for the verification of structural control algorithms. However, for nonlinear behavior, experiments are mostly destructive tests that are costly, and conducting repetitive structural experiments is difficult. Therefore, a repetitive structural vibration model is important for structural vibration control. In this study, a smart platform to realize different structural behaviors is developed based on the backstepping control algorithm. Lyapunov functions are used to derive the control law. Simulations show that the designed model can track the structural responses of different arbitrary linear structures very well. In addition, the proposed platform can track responses of different piecewise linear structures and desired models with various hysteresis very well. Numerical results verify the effectiveness of the proposed tracking controller through the backstepping method for the established platform.

关键词： repetitive model backstepping controller piecewise linear hysteresis

An Efficient Synthesis of Aromatic 1-Hydroxymethylene-1, 1-bisphosphonates from Aldehydes

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Chinese Chemical Letters 2003年第1期14卷 25-28页

作者： yu Li XIE qin ZHU StateKeyLaboratoryofDrugResearch ShanghaiInstituteofMateriaMedicaShanghaiInstitutesforBiologicalSciencesShanghai200031 StateKeyLaboratoryofDrugResearch ShanghaiInstituteofMate

A simple and efficient procedure for synthesis of 1-hydroxymethylene-1,1-bisphos- phoates from aldehydes is described. This method was applied to the synthesis of novel catechol substituted bisphosphonates as the a... 详细信息

关键词： Bisphosphonate aldehydes catechol anti-osteoporosis.