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Networked predictive Output Feedback Control of Networked Control Systems

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Networked Predictive Output Feedback Control of Networked Co...

Chaotic attitude and reorientation maneuver for completely liquid-filled spacecraft with flexible appendage

第三十届中国控制会议

作者： ZHANG Jinhui~1,XIA Yuanqing~2 1.College of Information Science & Technonlgy,beijing University of Chemical technology,beijing 100029,p.r.china 2.school of automation,beijing institute of technology,beijing 100081,p.r.china

＜正＞This paper is concerned with the design of packet-based output feedback controller for networked control systems （NCSs） with random network delay and data *** taking the full advantage of the packet-based transmission in NCSs, a packet-based control approach is proposed to actively compensate the delay and data dropout under Markovian jump linear system *** from previously reported packet-based control approaches to NCSs,an output feedback strategy is used to generate the control input packet.A new necessary and sufficient condition is proposed to perform the stability analysis of networked closed-loop ***,by using the recently established singular Markovian jump system theory,the controller design problem is ***,the effectiveness of the proposed method is illustrated by using a numerical example.

关键词： Data Dropout Networked Control Systems(NCSs) random Delay

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Acta Mechanica Sinica 2009年第2期25卷 271-277页

作者： B. Yue Department of Mechanics, school of Science,beijing institute of technology, 100081 beijing, china Department of Mechanics School of Science Beijing Institute of Technology 100081 Beijing China

The present paper investigates the chaotic attitude dynamics and reorientation maneuver for completely viscous liquid-filled spacecraft with flexible appendage. All of the equations of motion are derived by using Lagrangian mechanics and then transformed into a form consisting of an unperturbed part plus perturbed terms so that the system＇s nonlinear characteristics can be exploited in phase space. Emphases are laid on the chaotic attitude dynamics produced from certain sets of physical parameter values of the spacecraft when energy dissipation acts to derive the body from minor to major axis spin. Numerical solutions of these equations show that the attitude dynamics of liquid-filled flexible spacecraft possesses characteristics common to random, non- periodic solutions and chaos, and it is demonstrated that the desired reorientation maneuver is guaranteed by using a pair of thruster impulses. The control strategy for reorientation maneuver is designed and the numerical simulation results are presented for both the uncontrolled and controlled spins transition.

关键词： Nonlinear attitude dynamics Attitude reorientation maneuver Control strategyLiquid-filled spacecraft

The effects of relative density of metal foams on the stresses and deformation of beam under bending

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Acta Mechanica Sinica 2007年第4期23卷 409-414页

作者： Aiyu Zhu Tianyou Fan Department of Mathematics,school of Science,beijing institute of technology,p.O.Box 327,beijing 100081,china Department of physics,school of Science,beijing institute of technology,p.O.Box 327,beijing 100081,china Department of Mathematics School of Science Beijing Institute of Technology P. O. Box 327 Beijing 100081 China Department of physics School of Science Beijing Institute of Technology P. O. Box 327 Beijing 100081 China

The exact analytic solution of the pure bending beam of metallic foams is given. The effects of relative density of the material on stresses and deformation are revealed with the Triantafillou and Gibson constitutive law （TG model） taken as the analysis basis. Several examples for individual foams are discussed, showing the importance of compressibility of the cellular materials. One of the objects of this study is to generalize Hill＇s solution for incompressible plasticity to the case of compressible plasticity, and a kinematics parameter is brought into the analysis so that the velocity field can be determined.

关键词： Metal foams - relative density Compressible plasticity Constitutive law - TG model

Cutting performance and Mechanism of rE Carbide Tools

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rare Metals 2001年第3期20卷 197-201页

作者： Jianbing Cheng, Yufang Wu, Qixun Yu 1) Department of Mechanical Engineering, beijing technology and Business University, beijing 100037, china 2) College of Mechanical Engineering and automation, beijing institute of technology beijing 100081, china beijing Technol & Business Univ Dept Mech Engn Beijing 100037 Peoples R China beijing Inst Technol Coll Mech Engn & Automat Beijing 100081 Peoples R China

The research of rare earth elements (rE), added into cemented carbide tools, is one of the recent developments of new types of tool materials in china. Systematic experiments about rE carbides YG8r. (K30), YT14r (p20) and, YW1r (M10) were made to study on the cutting performance in comparison with non-rE carbides YG8, YT14 and YW1. The cutting experiments were as follows: tool life, cutting force, tool-chip friction coefficient and interrupted machining. The action of rE on the carbide materials and the cutting mechanism of the rE carbide tools in the cutting process were verified with the aid of SEM and energy spectrum analysis. Experimental results show that the rE carbide tools have a good overall performance.

关键词： rare earth elements cemented carbide tool cutting performance cutting mechanism

Augmented reality registration algorithm based on nature feature recognition

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Science china(Information Sciences) 2010年第8期53卷 1555-1565页

作者： CHEN Jing 1 , WANG YongTian 1,2 , GUO JunWei 1 , LIU Wei 1 , LIN JingDun 1 , XUE Kang 1 , LIU Yue 1 & DING GangYi 31 school of Optoelectronics, beijing institute of technology, beijing 100081, china 2.school of Computer Science and technology, beijing institute of technology, beijing 100081, china 3 school of Software, beijing institute of technology, beijing 100081, china 1. school of Optoelectronics Beijing Institute of Technology Beijing 100081 China2. School of Computer Science and Technology Beijing Institute of Technology Beijing 100081 China3. School of Software Beijing Institute of Technology Beijing 100081 China

This paper presents an improved key frame based augmented reality registration algorithm for real-time motion tracking in outdoor environment. In such applications, wide-baseline feature matching is a critical problem. In this paper, we apply randomized tree method to match key points extracted from the input image to those key frames as a classification problem. Extended Kalman filter is also utilized for jitter correction. A video see-through mobile augmented reality system is built for the on-site digital reconstruction of Yuanmingyuan Garden. Experimental results demonstrate that this algorithm is real-time, robust and effective for outdoor tracking.

关键词： outdoor augmented reality camera tracking randomized tree

The relative generalized Hamming weight and the semilinear equivalence of codes

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Science china(Information Sciences) 2011年第4期54卷 787-794页

作者： LIU ZiHui 1 & WANG Jie 2 1 Department of Mathematics,beijing institute of technology,beijing 100081,china 2.school of Mathematical Sciences,beijing University,beijing 100871,china 1. Department of Mathematics Beijing Institute of Technology Beijing 100081 China2. School of Mathematical Sciences Beijing University Beijing 100871 China

Certain equivalent conditions are given for the semilinear equivalence of linear codes by using the relative generalized Hamming weight and the value function.

关键词： value function semilinear equivalence support weight relative generalized Hamming weight

On the stability of diffusion processes with state-dependent switching

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Science china Mathematics 2006年第9期49卷 1258-1274页

作者： XI Fubao & ZHAO Liqin Department of Mathematics, beijing institute of technology, beijing 100081, china school of Mathematical Sciences, beijing Normal University, beijing 100875, china Department of Mathematics Beijing Institute of Technology Beijing 100081 China school of Mathematical Sciences Beijing Normal University Beijing 100875 China

In this paper we consider the stability for diffusion processes with state-dependent switching. We first prove their Feller continuity by the coupling methods. Furthermore, we also prove their strong Feller continuity and their exponential ergodicity under some reasonable conditions. Finally, we append a very brief discussion about the regularity of these processes.

关键词： Feller continuity, coupling, strong Feller continuity, exponential ergodicity,state-dependent switching.

Visualization of protein recr in Escherichia coli by fluorescent labelling

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progress in Natural Science:Materials International 2009年第11期19卷 1545-1551页

作者： Jiefang Qiu,Xuefeng pan~* school of Life Science,beijing institute of technology,beijing 100081,china [a]school of Life Science Beijing Institute of Technology Beijing 100081 China

recr protein,a functional equivalent of rad52 in eukaryotes,plays a critical role in the recF pathway of homologous recombination in Escherichia *** constructing and expressing the recr-yfp hybrid gene,the distribution of the recr-YFp fusion protein was visualized in *** by fluorescent *** results showed that recr proteins can be localized predominantly in the nucleoid region of *** measuring the UV resistance of a recr mutant carrying the recr-yfp gene in the plasmid,the expressed recr-YFp was found to be functional in improving the UV resistance of the recr deficiency strain.

关键词： recr YFp DNA repair Homologous recombination E.coli

A new DNA algorithm to solve graph coloring problem

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progress in Natural Science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1, Li Yin2, Meng Ya3 and Meng Dazhi2(1. National Laboratory of pattern recognition,institute of automation, Chinese Academy of Sciences, beijing 100080, china 2. College of Applied Sciences, beijing University of technology, beijing 100022, china 3. school of Science, beijing institute of technology, beijing 100081, china) National Laboratory of pattern recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China College of Applied Sciences Beijing University of Technology Beijing 100022 China school of Science Beijing Institute of Technology Beijing 100081 China

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some Np-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6r DNA encoding molecules if the number of regions in a graph is r).

关键词： DNA computing Np-hard problem graph coloring problem.