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welding research in{2.

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china welding 1994年第2期3卷 90-96页

作者： ZHOU Zhaowei(harbin research Institute of {2.({3.))

in this article,the author touches on welding research system,current welding research, and introduces recent achievements in welding research in china.

关键词： welding research in{2.

Survey on Chinese welding consumables

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china welding 1994年第2期3卷 138-141页

作者： ZHAO Lisan (harbin research Institute of {2. ({3.))

In china, the main products of welding consumables consist of covered electrode, welding wire, flux, brazing filler and flux and so on. This paper introduces the status of the main welding consumables. It points out that along with the technical progress and the development of new materials, welding consumables will have a great growth in the next ten year.

关键词： Survey on Chinese welding consumables

research on the application of 4-weighted fractional Fourier transform in communication system

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Science china(Information Sciences) 2010年第6期53卷 1251-1260页

作者： MEI Lin 1, SHA XueJun 1 , RAN QinWen 2.& ZHANG NaiTong 1 1 Communication research Center, harbin Institute of Technology,{2., china 2.Science research Center, harbin Institute of Technology,{2., china 1. Communication research Center Harbin Institute of Technology Harbin 150080 China2. Science Research Center Harbin Institute of Technology Harbin 150080 China

The paper reveals the relationship between the weighting coefficients and weighted functions via the research of coefficients matrix and based on the original definition of 4-weighted fractional Fourier transform(4-WFRFT).The multi-parameters expression of weighting coefficients are ***, the 4-WFRFT of discrete sequences is defined by introducing DFT into it, which makes it suitable for digital communication *** analyzing the properties of WFRFT, a typical scheme for modulation/demodulation is proposed, which could make the statistics properties of the real and image part on both of the time and frequency domain and the phase properties have a significant *** a variation could be controlled by the adjustment of transform *** the WFRFT of multi-parameters is implemented, it will be more difficult to intercept and capture the modulated signals than normal.

关键词： 4-weighted fractional Fourier transform modulation/demodulation scheme multi-domain cooperation

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, {2. harbin, china Deep Space Exploration research Center Harbin Institute of Technology 150080 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

Uniqueness and stability in an inverse problem for a Poisson's equation

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Science china Mathematics 2007年第7期50卷 967-976页

作者： Li-xin FENG~(1+) Yan-cheng QU~2.1 School of Mathematical Sciences,Heilongjiang University,harbin 150080,{2. 2.research Center of Control and Inertial Technology,harbin Institute of Technology,harbin 150001,{2. 1. School of Mathematical Sciences Heilongjiang University Harbin 150080 China 2. research Center of Control and Inertial Technology Harbin Institute of Technology Harbin 150001 China

Consider the Poisson’s equation Ψ″ (x) = ?e v?Ψ + e Ψ?v ? N(x) with the Dirichlet boundary data, and we mainly investigate the inverse problem of determining the unknown function N(x) from a parameter function fa... 详细信息

关键词： Poisson’s equation well-posedness inverse problem 65N3. 3.R3.

Structure and kinematic analysis of a novel 2.DOF translational parallel robot

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Progress in Natural Science:Materials International 2007年第10期17卷 1213-1219页

作者： Chen Tao1, Wu Chao2.and Liu Xinjun2.1. School of Application Science and Technology, harbin University of Science and Technology,{3.,{2. 2. Department of Precision Instruments, Tsinghua University, Beijing 100084,{2.) School of Application Science and Technology Harbin University of Science and Technology Harbin 150080 China Department of Precision Instruments Tsinghua University Beijing 100084 China

This paper addresses the analysis of a novel parallel robot with 2.translational degrees of freedom (DOFs). The robot can position a rigid body in a plane with constant orientation. The kinematic structure of the robot is first described in detail. Some kinematic problems, such as the inverse and forward kinematics, velocity, and singularity are then analyzed. The working and assembly modes are discussed. Since it is the most important index to design a robot, the workspace of the robot is studied systematically in this paper. Based on the analysis of reachable workspace and singularity, a kind of workspace concept characterizing the region that the end-effector of the robot can reach in practice is defined. The results of this paper will be very useful for the design and application of the robot.

关键词： parallel robot degree of freedom kinematics workspace.

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,{3. Post-doctoral research Center in Material Science and Engineering,harbin Institute of Technology,150001 harbin,{3. 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

Effects of binders on the performance of electric double-layer capacitors of carbon nanotube electrodes

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Progress in Natural Science:Materials International 2005年第5期15卷 453-457页

作者： LI Chensha1*, WANG Dazhi1, ZHANG Baoyou2. WANG Xiaofeng1, CAO Maosheng3. and LIANG Ji1(1. Department of Mechanical Engineering, Tsinghua University, Beijing 100084, china 2. Center for Analysis and Measurement, {3. Institute of Technology, {3. 150001, china 3. School of Material Science and Engineering, Tsinghua University, Beijing 100084, china) Department of Mechanical Engineering Tsinghua University Beijing 100084 China Center for Analysis and Measurement Harbin Institute of Technology Harbin 150001 China School of Material Science and Engineering Tsinghua University Beijing 100084 China

Polarizable electrodes of electric double layer capacitor (EDLCs) were made from carbon nanotubes. Effects of different binders, which are phenolic resin (PF) and polytetrafluoroethylene (PTFE), on the properties of polarizable electrodes are studied. Results indicate that the microstructure, pore size distribution and specific capacitance of the electrodes with PTFE binder are superior to those electrodes with PF binder after carbonization. The suitable binder (PTFE) for carbon nanotubes electrodes is proposed.

关键词： carbon nanotubes electric double-layer capacitors phenolic resin polytetrafluoroethylene.

Current status and prospects of welding technology in china

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china welding 1994年第2期3卷 79-89页

作者： SONG Tianhu (research Institute of Machinery Science and Technology,Beijing (100044))WU Yunfei (harbin research Institute of {3. (150080))

In this paper the history of welding technology and the current status in china was reviewed, and based on the situation the developmental trend was prospected.

关键词： Current status and prospects of welding technology in china