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FORMATION OF AMORPHOUS Ni-Ti ALLOY BY MECHANICAL ALLOYING

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中国有色金属学会会刊：英文版 1994年第4期4卷 83-86,90页

作者： Liang Guoxian Wang Erde Li Zhiming(college of Materials science and engineering, harbin Institute of Technologg,harbin 150001)

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关键词： mechanical alloying Ni-Ti alloys amorphization

An Anthropomorphic Robot Hand Developed Based on Underactuated Mechanism and Controlled by EMG Signals

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Journal of Bionic engineering 2009年第3期6卷 255-263页

作者： Da-peng Yang~1 Jing-dong Zhao~1 Yi-kun Gu~1 Xin-qing Wang~1 Nan Li~1 Li Jiang~1Hong Liu~(1,2) Hai Huang~3 Da-wei Zhao~41.State Key Laboratory of Robotics and System,harbin Institute of Technology,harbin 150001,P.R.china2.Institute of Robotics and Mechatronics,German Aerospace Center,Munich 82230,Germany3.college of Shipbuilding engineering,harbin engineering university,harbin 150001,P.R.china4.college of Automation,harbin engineering university,harbin 150001,P.R.china [a]State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150001 P. R. China [b]Institute of Robotics and Mechatronics German Aerospace Center Munich 82230 Germany [c]College of Shipbuilding Engineering Harbin Engineering University Harbin 150001 P. R. China [d]College of Automation Harbin Engineering University Harbin 150001 P. R. China

When developing a humanoid myo-control hand,not only the mechanical structure should be considered to afford a high dexterity,but also the myoelectric (electromyography,EMG) control capability should be taken into account to fully accomplish the actuation *** paper presents a novel humanoid robotic myocontrol hand (AR hand Ⅲ) which adopted an underac- tuated mechanism and a forearm myocontrol EMG *** AR hand Ⅲ has five fingers and 15 joints,and actuated by three embedded *** can be found within each finger and between the rest three fingers (the middle finger,the ring finger and the little finger) when the hand is grasping *** the EMG control,two specific methods are proposed:the three-fingered hand gesture configuration of the AR hand Ⅲ and a pattern classification method of EMG signals based on a statistical learning algorithm-Support Vector Machine (SVM).Eighteen active hand gestures of a testee are recognized ef- fectively,which can be directly mapped into the motions of AR hand Ⅲ.An on-line EMG control scheme is established based on two different decision functions:one is for the discrimination between the idle and active modes,the other is for the recog- nition of the active *** a result,the AR hand Ⅲ can swiftly follow the gesture instructions of the testee with a time delay less than 100 ms.

关键词： humanoid hand underactuated mechanism EMG control suppon vector machine

A video encryption method based on chaotic maps in DCT domain

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Progress in Natural science:Materials International 2008年第10期18卷 1299-1304页

作者： Shuguo Yang~(a,b,*) Shenghe Sun~a ~a School of Electrical engineering and Automation,harbin Institute of Technology,harbin 150001,china ~b Qingdao university of science and Technology,Qingdao 266061,china School of Electrical engineering and Automation Harbin Institute of Technology Harbin 150001 China Qingdao university of science and Technology Qingdao 266061 China

This paper proposes a new and secure video encryption method based on chaotic maps in DCT domain,which is quite in keeping with the common ideas and the frequent practices of video *** select the I-frames of the video sequence as encryption objects. First,we introduce two coupling chaotic maps to scramble the DCT coefficients of every original I-frame,and receive the scrambled ***,we encrypt the DCT coefficients of the scrambled 1-frame using another chaotic *** the whole process,we use three chaotic maps and five keys;the I-frame is encrypted ***,we performed several tests and the experimental results have proved our method to be secure and efficient.

关键词： Video encryption Chaotic map I-frame Scrambling Video sequence

Method of coupled mode for long-range bottom reverberation

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science china(Physics,Mechanics & Astronomy) 2010年第12期53卷 2216-2222页

作者： GAO Bo , YANG ShiE, PIAO ShengChun & HUANG YiWang National Laboratory of Underwater Acoustic Technology,harbin engineering university, harbin 150001, china 1. National Laboratory of Underwater Acoustic Technology Harbin Engineering University Harbin 150001 China

The theory of coupled mode is used for modeling the long-range bottom reverberation in shallow water caused by bottom roughness. The distant bottom reverberation level and spatial coherence of impulsive source are both derived. The results agree with those from the classical reverberation model, and are compared with the experimental data. The influence of source bandwidth and the distance between sources and receivers on the intensity of bottom reverberation are particularly discussed. The method is shown to be available for both the monoand the bi-static cases.

关键词： shallow water couple mode bottom reverberation

Erosive Wear and Wear Mechanism of in situ TiC_P/Fe Composites

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Journal of Materials science & Technology 2005年第5期21卷 719-723页

作者： Zhaojing LIU, Zhiliang NING , Fengzhen LI, Xiurong YAO and Shanzhi RENSchool of Materials science and engineering, harbin university of science and Technology, harbin 150080, china School of Materials science and engineering Harbin University of Science and Technology Harbin 150080 China

The base structure of in situ TiCp/Fe composites fabricated under industrial condition was changed by different heat treatments. Erosive wear tests were carried out and the results were compared with that of wear-resistant white cast iron. The results suggest that the wear resistance of the in situ TiCp/Fe composite is higher than that of wear-resistant white cast iron under the sand erosive wear condition. The wear mechanism of the wear-resistant white cast iron was a cycle process that base surface was worn and carbides were exposed, then carbides was broken and wear pits appeared. While the wear mechanism of in situ TiCp/Fe composite was a cycle process that base surface was worn and TiC grains were exposed and dropped. The wear resistance of in situ TiCp/Fe composite was lower than that of wear-resistant white cast iron under the slurry erosive wear condition. Under such circumstance, the material was not only undergone erosive wear but also electrochemistry erosion due to the contact with water in the medium. The wear behaviours can be a combination of two kinds of wear and the sand erosive wear is worse than slurry erosive wear.

关键词： In situ TiCp/Fe composite Erosive wear Wear mechanism

Prediction of Mechanical Properties of 50CrVA Tempered Steel Strip for Horn Diaphragm Based on BPANN

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Journal of Wuhan university of Technology(Materials science) 2009年第5期24卷 791-795页

作者：江树勇 engineering Training Center Harbin Engineering University

50CrVA cold-rolled spring steel strip was used to fabricate the diaphragm of the automotive horn. The material parameters which were taken into account in the design of the dia-phragm involve elongation, elastic limit, Young＇s modulus, yield strength and tensile strength. The tempering process was carried out in order to enable the diaphragm to possess the excellent mechanical properties, such as high elastic limit, high fatigue strength and perfect stress relaxation resistance. As a nonlinear information processing system, the backpropagation artificial neural network （BPANN） was applied to predict and simulate the relationship between the mechanical properties of the diaphragm and the tempering process parameters. Experimental results show that a BPANN with 3-8-5 architec-ture is capable of predicting the relationship between the mechanical properties of the diaphragm and the tempering temperature successfully and lays the profound foundations for optimizing the design of the diaphragm. BPANN simulation results show that the tempering temperature ranging from 380 to 420 ℃ contributes to enhancing the comprehensive mechanical properties of the diaphragm including high Young＇s modulus, high elastic limit and high fatigue strength.

关键词： artificial neural networks mechanical properties tempering diaphragm 50CrVA

Influences of prolate spheroidal baffle of sound diffraction on spatial directivity of acoustic vector sensor

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science china(Technological sciences) 2010年第10期53卷 2846-2852页

作者： JI JianFei, LIANG GuoLong, WANG Yan & LIN WangSheng National Laboratory of Underwater Acoustic Technology, harbin engineering university, harbin 150001, china 1. National Laboratory of Underwater Acoustic Technology Harbin Engineering University Harbin 150001 China

The directivity of acoustic vector sensor (AVS) will be distorted by the sound diffraction of the AVS carrier. In this paper,the scattering of a plane acoustic wave from a prolate spheroid baffle is considered. At first,the sound diffraction of prolate spheroidal baffle is established,then the mathematical expressions of sound pressure field and particle vibration velocity field of sound diffraction are derived and the characteristic of the directivity of pressure and velocity of sound diffraction field at different frequencies and distances is analyzed. The directivity of AVS is determined by the amplitude and phase difference of diffraction wave and incident wave,which possesses a close relationship with frequency and incident angle. Finally,the calculated results are compared with the experimental results.

关键词： prolate spheroidal baffle sound diffraction field spatial directivity vector sensor

Neural integrated control for a free-floating space robot with suddenly changing parameters

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science china(Information sciences) 2011年第10期54卷 2091-2099页

作者： ZHANG WenHui 1,2 ,QI NaiMing 2,MA Jing 1,3 & XIAO AYang 2 1 School of Electromechanical engineering,Xuzhou Normal university,Xuzhou 221116,china 2 School of Aerospace,harbin Institute of Technology,harbin 150001,china 3 Department of engineering,Northeast Agricultural university,harbin 150001,china 1. School of Electromechanical engineering Xuzhou Normal University Xuzhou 221116 China2. School of Aerospace Harbin Institute of Technology Harbin 150001 China3. Department of Engineering Northeast Agricultural University Harbin 150001 China

Because the state of a free-floating space robot model is uncertain and sudden changes in the model parameters might undermine the stability of the system,this paper proposes a control strategy based on a variable structure neural integrated *** scheme does not need a precise space robot model,making use of the radial basis function neural network ability approach to learn about an uncertain *** network weights are adjusted online in *** the early period of the control phase and parameter changes,the variable structure controller compensates for the uncertain model which the neural network could not learn *** also creates global asymptotic stability for the whole closed-loop *** results show that the controller can handle bad changeable conditions and has important application value for defense,aerospace and other major security fields.

关键词： neural network variable structure adaptive control global asymptotical stability

Landscape Change and its effect on the environment of Daqing City

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Progress in Natural science:Materials International 2005年第7期15卷 641-649页

作者： ZANG Shuying, ZHANG Jing and JIA Li ( college of Life and Environment science, harbin Normal university, harbin 150080, china college of Resources Environment & Tourism, Capital Normal university, Beijing 100037, china college of Economics and Management, Northeast Agricultural university, harbin 150030, china) college of Life and Environment science Harbin Normal University Harbin 150080 China. college of Resources Environment & Tourism Capital Normal University Beijing 100037 China. college of Economics and Management Northeast Agricultural University Harbin 150030 China

In this paper, we will study the temporal-spatial landscape change from 1978 to 2001 in Daqing City, based on the mul- ti spectral scanner (MSS) and thematic mapper (TM) images of remote sensing (RS) of 1978, 1988, 1992, 1996 and 2001. In order to explain the effects of the component change on the whole landscape, we make a statistic analysis about the transfer probability matrix of the component types of the landscape by using the ARCGIS platform through the overlay analysis of different landscape components. Based on the transfer probability matrix, we calculate the in-transfer ratio, the out-transfer ratio and the contributor ratio of the special transfer process of the main landscape components. The results illustrate that the cultivated-land, grassland, swamp, and alkaline land are the main contributors resulting in the landscape change: the out-transfer ratios of grassland and swamp are much higher than the in-transfer ones; the in-transfer ratio of alkaline land is much higher than the out-transfer one; the in-transfer ratio of the land-lot is always higher than its out-transfer with the highest rate per year, although there is a small difference among the in-transfers and the out-transfers per year. The main landscape changing processes are the salination of cultivated-land, salination or desertification of grassland, salination and degeneration of swamp. Results in this paper can provide scientific basis for investigating the landscape change mechanism of resources-based city.

关键词： landscape change environmental effect transfer probability resources-based city.