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A Novel Stable Clustering Design Method for Hierarchical Satellite Network

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Chinese Journal of Aeronautics 2010年第1期23卷 91-102页

作者： Zhou Mu,Guo Qing,Wang Zhenyong Communication research center,School of Electronics and Information Engineering,harbin institute of technology,harbin 150001,china Communication research center School of Electronics and Information Engineering Harbin Institute of Technology Harbin 150001 China

This article proposes a novel stable clustering design method for hierarchical satellite network in order to increase its stability,reduce the overhead of storage and exert effective control of the delay performances based on a 5-dimensional vector model. According to the function of stability measureinent and owing to the limitation of minimal average routing table length, the hierarchical satellite network is grouped into separate stable connected clusters to improve destruction resistance and reconstruction ability in the future integrated network. In each cluster, redundant communication links with little contribution to network stability and slight influences on delay variation are deleted to satisfy the requirements for stability and connectivity by means of optimal link resources, and, also, the idea of logical weight is introduced to select the optimal satellites used to communicate with neighboring cluster satellites. Finally, the feasibility and effectiveness of the proposed method are verified by comparing it with the simulated performances of other two typical hierarchical satellite networks, double layer satellite constellation（DLSC） and satellite over satellite（SOS）.

关键词： satellite network hierarchical structure stability analysis clustering algorithms vector measurements

Wrinkle-crease interaction behavior simulation of a rectangular membrane under shearing

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Acta Mechanica Sinica 2011年第4期27卷 550-558页

作者： C.-G.Wang.H.-F.Tan.X.-D.He center for Composite Materials,harbin institute of technology,150080 harbin,china Post-doctoral research center in Material Science and Engineering,harbin institute of technology,150001 harbin,china center for Composite Materials Harbin Institute of Technology Harbin China Post-doctoral research center in Material Science and Engineering Harbin Institute of Technology Harbin China

Wrinkling analysis of a rectangular membrane with a single crease under shearing is performed to understand the wrinkle-crease interaction behaviors. The crease is considered by introducing the residual stresses from creasing and the effective modulus into the baseline configuration with assumed circular cross-sectional crease geometry. The wrinkling analysis of the creased membrane is then performed by using the direct perturb-force （DP） simulation technique which is based on our modified displacement components （MDC） method. Results reveal that the crease may influence the stress transfer path in the membrane and further change the wrinkling direction. The crease appears to improve the bending stiffness of the membrane which has an effective resistance on the wrinkling evolution. The effects of the crease orientation on wrinkle-crease interaction are studied toward the end of this paper. The results show that the wrinkling amplitude, wavelength, and direction increase as the crease orientation increases, and the wrinkling number decreases with the increasing crease orientation. These results will be of great benefit to the analysis and the control of the wrinkles in the membrane structures.

关键词： Membrane structure - Wrinkle-crease interac-tion Membrane wrinkling Creased membrane

Study on the Class-Based Admission control Scheme for DiffServ in MPLS Networks

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Journal of Systems Engineering and Electronics 2003年第3期14卷 40-44页

作者： Li Zhenyu , Zhang Zhongzhao Communication research center, harbin institute of technology, harbin 150001, P. R. china Communication research center Harbin Institute of Technology Harbin 150001 P. R. China

Differentiated services (DiffServ) and MPLS are two major building blocks for providing multi-class services over IP networks. In order to respond to the need for relatively simple, coarse methods of providing different levels of service for Internet traffic, to support various types of applications and specific business requirements, the MPLS network infrastructure and the DiffServ traffic model will work together. Meanwhile, in today’s environment of multiple service networks, it is necessary for the node in the networks to perform the control mechanism to guarantee various QoS. In

关键词： MPLS DiffServ Admission control.

Experimental Study of Monitoring and controlling of Composite Cure Process in Autoclave Featured with Fiber Optic Sensor

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Journal of Materials Science & technology 2001年第4期17卷 449-452页

作者： Boming ZHANG, Zhanjun WU , Dianfu WANG and Shanyi DU center for composite, harbin institute of technology harbin 150001, china Cent. for Composite Harbin Inst. of Technol. Harbin 150001 China

With the aid of the latest fiber optic sensing technology parameters in the cure process of ther- mosetting resin-matrix composite, such as temperature, viscosity,void and residual stress, can be monitored entirely and *** this paper, experiment results of viscosity measurement in composite cure process in autoclave using fiber optic sensors are presented. Based on the sensed information, a computer program is utilized to control the cure process. With this technology, the cure process becomes more apparent and controllable, which will greatly improve the cured products and reduce the cost.

关键词： Experimental Study of Monitoring and controlling of Composite Cure Process in Autoclave Featured with Fiber Optic Sensor

An improved nonlinear control strategy for deep space formation flying spacecraft

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Acta Mechanica Sinica 2009年第6期25卷 847-856页

作者： Peng Li Pingyuan Cui Hutao Cui Deep Space Exploration research center,harbin institute of technology, 150080 harbin, china Deep Space Exploration research center Harbin Institute of Technology Harbin China

This paper aims to provide further study on the nonlinear modeling and controller design of formation flying spacecraft in deep space missions. First, in the Sun-Earth system, the nonlinear formation dynamics for the circular restricted three-body problem （CRTBP） and elliptic restricted three-body problem （ERTBP） are presented. Then, with the Floquet mode method, an impulsive controller is developed to keep the Chief on the desired Halo orbit. Finally, a nonlinear adaptive control scheme based on Nonzero set- point LQR and neural network is proposed to achieve high precision formation maneuver and keeping. The simulation results indicate that the proposed nonlinear control strategy is reasonable as it considers not only the orbit keeping of the Chief, but also the formation modeling inaccuracy. Moreover, the nonlinear adaptive control scheme is effective to improve the control accuracy of the formation keeping.

关键词： Spacecraft formation flying. Libration pointHalo orbit - Nonlinear control

ROBUST H_∞ FILTERING FOR UNCERTAIN DISCRETE-TIME STATE-DELAYED SYSTEMS: A PARAMETER-DEPENDENT LYAPUNOV APPROACH

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Journal of Systems Science & Complexity 2004年第3期17卷 399-411页

作者： GAOHuijun WANGChanghong Spacecontrolandinertialtechnologyresearchcenter HarbinInstituteofTechnologyHarbin150001China

This paper is concerned with the problem of robust H∞ filtering for linear discrete-time systems with multiple state delays and polytopic uncertain parameters. Attention is focused on the design of full-order, reduced-order and zeroth-order robust H∞ filters on the basis of a recently published parameter-dependent Lyapunov stability result. Sufficient conditions for the existence of such filters are formulated in terms of linear matrix inequalities, upon which admissible filters can be obtained from convex optimization problems. The proposed methodology has been shown, via a numerical example, to be much less conservative than previous filter design methods in the quadratic framework.

关键词： robust H_∞ filtering linear matrix inequality polytopic uncertainty parameter-dependent stability time-delay systems

Monocular vision-based iterative pose estimation algorithm from corresponding feature points

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Science china(Information Sciences) 2010年第8期53卷 1682-1696页

作者： ZHANG ShiJie 1 , CAO XiBin 1 , ZHANG Fan 1 & HE Liang 2 1 research center of Satellite technology, harbin institute of technology, harbin 150080, china 2 Shanghai Aerospace control Engineering institute, Shanghai 200233, china research center of Satellite technology Harbin Institute of Technology Harbin China Shanghai Aerospace control Engineering institute Shanghai China

To determine the relative pose between an object and a single camera using 2D-to-3D point correspondences, a kind of iterative methods based on inverse projection ray approach is proposed. An iterative algorithm which is divided into depth recovery stage and absolute orientation stage is also proposed. In the first stage, the optimal translation vector is first computed in terms of rotation matrix via least square method, then the depths of the observed points are estimated by projecting the estimated point orthogonally to the inverse projection ray defined by the image point, and finally 3D points are reconstructed using the estimated depths from previous step. In the second stage, the optimal rotation matrix is estimated by applying Umeyama algorithm to fitting of the 3D model points and 3D estimated points. The above two stages are repeated until the result converges. The global convergence of the two-stage iterative algorithm is proven based on the global convergence theorem. Finally, a spacecraft docking application is implemented to test the effectiveness and convergence of the proposed algorithm by mathematical simulation and physical simulation.

关键词： monocular vision feature point relative pose two-stage iterative algorithm global convergence

GLOBAL STABILIZATION OF LINEAR SYSTEMS WITH BOUNDED controlS USING STATE-DEPENDENT SATURATION FUNCTIONS

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Journal of Systems Science & Complexity 2011年第3期24卷 477-490页

作者： Bin ZHOU Guangren DUAN He KONG center for control Theory and Guidance technology Harbin Institute of Technology Harbin 150001 China.

By using the so-called SP-stable polynomials, this paper reconsiders the problem of global stabilization of linear systems with input saturation. Firstly, a new nonlinear feedback law consisting of parallel connections of saturation functions by means of the so-called state-dependent saturation function is proposed for global stabilization of chains of integrators system. The state-dependent saturation function allows increasing the control energy when some of the states are badly scaled and can improve significantly the transient performances of the closed-loop system. Secondly, this type of global stabilization nonlinear feedback laws is extended to a class of linear systems that can be globally stabilized by bounded controls. Numerical examples show the effectiveness of the proposed approach.

关键词： Bounded feedback global stabilization nonlinear control state-dependent saturation functions SP-stable polynomials.

Stability of linear discrete switched systems with delays based on average dwell time method

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Science china(Information Sciences) 2010年第6期53卷 1216-1223页

作者： WANG Yong 1 , WANG Wei 1 & LIU GuoPing 2,3 1 research center of Information and control, Dalian University of technology, Dalian 116024, china 2 Faculty of Advanced technology, University of Glamorgan, Pontypridd, CF37 1DL, UK 3 CTGT center in harbin institute of technology, harbin 150001, china research center of Information and control Dalian University of Technology Dalian China Faculty of Advanced technology University of Glamorgan Pontypridd UK CTGT center in harbin institute of technology Harbin China

This paper deals with the problem of exponential stability for a class of linear discrete switched systems with constant *** switched systems consist of stable and unstable *** on the average dwell time method, some switching signals will be found to guarantee exponential stability of these *** explicit state decay estimation is also given in the form of the solutions of linear matrix inequalities(LMIs).An example relating to networked control systems(NCSs) illustrates the effectiveness of the proposed method.

关键词： switched systems average dwell time time delay LMI