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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

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 efficiently.In 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

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.

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：健壮H∞滤波多元分布不确定性线性离散时间系统时间延迟系统线性矩阵不等式参数依赖稳定性状态估计

Experimental Study of Rat Beta Islet Cells Cultured under Simulated Microgravity Conditions

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Acta Biochimica et Biophysica Sinica 2004年第1期36卷 47-50页

作者： Chun SONG, Xiu-Qing DUAN, Xi LI, Li-Ou HAN, Ping XU, Chun-Fang SONG, and Lian-Hong JIN (Key Laboratory of Cell Transplantation of Ministry of Health, First Affiliated Hospital of harbin Medical University, harbin 150001, china Department of General Surgery, First Affiliated Hospital of harbin Medical University, harbin 150001, china National Key Laboratory of harbin Veterinary research institute of Chinese Agriculture Academy, harbin 150001, china Tissue Engineering research center, Histology and Embryology Staff Room, harbin Medical University, harbin 150086, china ) Key Laboratory of Cell Transplantation of Ministry of Health First Affiliated Hospital of Harbin Medical University Harbin 150001 China Department of General Surgery First Affiliated Hospital of Harbin Medical University Harbin 150001 China National Key Laboratory of harbin Veterinary research institute of Chinese Agriculture Academy harbin 150001 China Tissue Engineering research center Histology and Embryology Staff Room Harbin Medical University Harbin 150086 China

To observe the effects of simulated microgravity on beta islet cell culture, we have compared the survival rates and the insulin levels of the isolated rat islet cells cultured at micro- and normal gravity conditions. The survival rates of the cells cultured were determined by acridine orange-propidium iodide double-staining on day 3, 7 and 14. The morphology of the cells was observed by electron microscopy. Insulin levels were measured by radio immuno assays. Our results show that the cell number cultured under the microgravity condition is significantly higher than that under the routine condition (P<0.01). Some tubular structure shown by transmission electron microscopy, possibly for the transport of nutrients, were formed intercellularly in the microgravity cultured group on day 7. There were also abundant secretion particles and mitochondria in the cytoplasm of the cells. Scanning electron microscopy showed that there were holes formed between each islet, possibly connecting with the nutrient trans

关键词： simulated microgravity islet cell electron microscopy radioimmunoassay

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.

由使用所谓的 SP 稳定的多项式，这篇论文与输入浸透重新考虑线性系统的全球稳定的问题。第一，借助于所谓的州依赖者的浸透功能由浸透功能的平行连接组成的一条新非线性的反馈法律为综合者系统的链的全球稳定被建议。当一些状态糟糕显... 详细信息

由使用所谓的 SP 稳定的多项式，这篇论文与输入浸透重新考虑线性系统的全球稳定的问题。第一，借助于所谓的州依赖者的浸透功能由浸透功能的平行连接组成的一条新非线性的反馈法律为综合者系统的链的全球稳定被建议。当一些状态糟糕显著地被放大并且能改善靠近环的系统的短暂表演时，州依赖者的浸透函数允许增加控制精力。第二，这类全球稳定非线性的反馈法律被扩大到能被围住的控制全球性稳定的线性系统的一个班。数字例子显示出建议途径的有效性。

关键词：线性状态有界控制输入饱和全局镇定功能系统非线性反馈法全局稳定线性系统