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On the new results of global attractive set and positive invariant set of the Lorenz chaotic system and the applications to chaos control and synchronization

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Science in china(Series F) 2005年第3期48卷 304-321页

作者： LIAO Xiaoxin 1, 2. 3 , FU Yuli 4 & XIE Shengli 4 1. department of Control Science & Control engineering, Huazhong University of Science & {2., Wuhan 430074, china 2. School of Automation, Wuhan University of Science & {2., Wuhan 430070, china 3. School of Information, Central South University of Economy, Politics and Law, Wuhan 430064, china 4. School of Electronics & Information engineering, South china University of {2., Guangzhou 510640, china Correspondence should be addressed to Liao Xiaoxin (email: xiaoxin_liao@***) 1. department of Control Science & Control engineering Huazhong University of Science & Technology 430074 Wuhan China 2. School of Automation Wuhan University of Science & Technology 430070 Wuhan China 3. School of Information Central South University of Economy Politics and Law 430064 Wuhan China 4. School of Electronics & Information engineering South China University of Technology 510640 Guangzhou China

Constructing a family of generalized Lyapunov functions, a new method is proposed to obtain new global attractive set and positive invariant set of the Lorenz chaotic system. The method we proposed greatly simplifies the complex proofs of the two famous estimations presented by the Russian scholar Leonov. Our uniform formula can derive a series of the new estimations. Employing the idea of intersection in set theory, we extract a new Leonov formula-like estimation from the family of the estimations. With our method and the new estimation, one can confirm that there are no equilibrium, periodic solutions, almost periodic motions, wandering motions or other chaotic attractors outside the global attractive set. The Lorenz butterfly-like singular attractors are located in the global attractive set only. This result is applied to the chaos control and chaos synchronization. Some feedback control laws are obtained to guarantee that all the trajectories of the Lorenz systems track a periodic solution, or globally stabilize an unstable (or locally stable but not globally asymptotically stable) equilibrium. Further, some new global exponential chaos synchronization results are presented. Our new method and the new results are expected to be applied in real secure communication systems.

关键词： Lorenz chaotic system global attractive set positive invariant set globally exponential tracking globally exponential synchronization.

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Research on the Surface Micro-configuration in Vibration Cutting Particle Reinforced Metallic Matrix Composites SiC_p/Al

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厦门大学学报（自然科学版） 2002年第S1期41卷 71-72页

作者： ZHAO Bo 1,2. LIU Chuan-shao 2. ZHU Xun-sheng 1, XU Ke-wei 1 (1. institute of Mechanical engineering, Shanghai Jiaotong U niversity, Shanghai 2.0030,{2. 2. department of Mechanical engineering, Jiaozuo institute of technology, Hena n 454000,{2.)

The cutting performance of particulate reinforced me tallic matrix composites(PRMMCs) SiC p/Al in ultrasonic vibration cutting and c ommon cutting with carbide tools and PCD tools was researched in the paper. Mic rostructure of machined surface was described, the relation between cutting para meters and surface roughness was presented, and characteristic of the surface re mained stress was also presented. Furthermore, wear regularity and abrasion resi stance ability of tools in ultrasonic vibration cutting and common cutting o f PRMMCs were discussed in detail. The test results show: (1) The surface config urations are obviously different when using different tools to machine such PRMM Cs. The surface machined with carbide tools looks luminous and orderly and there are seldom surface defects on it. The reason is that the soft basal body is apt to flow during cutting, therefore a layer of Al matrix film covers machined sur face. On the contrary, the surface machined with PCD tools looks lackluster. But the profile of machined surface is very clear. Superfine grooves, pits and blac k reinforce particulates can be seen easily without obvious Al film. (2. Because of unstable cutting process in common cutting, the surface is easy to produce s ome defects such as burrs, built-up edges and so on so that the quality of surf ace becomes very poor. Vibration cutting can reduce the influence of tearing, pl astic deformation and built-up edge in cutting and can restrain flutter so as t o make cutting process more stable. Therefore, surface roughness of vibration cu tting is better than that of common cutting. (3) There is an optimum value of fe ed rate in vibration cutting of PRMMCs due to the influence of material characte ristics. Whether feed rate is more than or less than this optimum value, surface roughness will increase. (4) According to analyzing the wear rate of tools in v ibration cutting PRMMCs, it can be concluded that abrasion resistance of tools w ill be improved

关键词： PCD tools composite SiC p/Al surface micro-c onfiguration tool wear

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Autonomous forward inference via DNA computing

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Progress in Natural Science:Materials International 2007年第6期17卷 725-732页

作者： Fu Yan1, Li Gen2. Li Yin1 and Meng Dazhi1(1. DNA Computing Research Group, department of Operational Research and Cybernetics, institute of Applied Science, Beijing University of {2., Beijing 10002., china 2. department of Informatics and Mathematical Modeling, Technical University of Denmark, Copenhagen, Denmark) [a]DNA Computing Research Group Department of Operational Reseach and cybernetics Institute of Applied Science Beijing University of Technology Beijing China [b]department of Informatics and Mathematical Modeling Technical University of Denmark Copenhagen Denmark

Recent studies direct the researchers into building DNA computing machines with intelligence, which is measured by three main points: autonomous, programmable and able to learn and adapt. Logical inference plays an important role in programmable information processing or computing. Here we present a new method to perform autonomous molecular forward inference for expert system. A novel repetitive recognition site (RRS) technique is invented to design rule-molecules in knowledge base. The inference engine runs autonomously by digesting the rule-molecule, using a Class IIB restriction enzyme PpiI. Concentration model has been built to show the feasibility of the inference process under ideal chemical reaction conditions. Moreover, we extend to implement a triggering communication between molecular automata, as a further application of the RRS technique in our model.

关键词： RRS technique forward inference triggering communication molecular automaton.

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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 {2. and Business University, Beijing 100037, china 2. College of Mechanical engineering and Automation, Beijing institute of {2. 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 (P2.) 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

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Tensile and compression properties of Zr-based bulk amorphous alloy at different temperatures

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Science china(Technological Sciences) 2005年第5期48卷 489-495页

作者： WANG Xu1,3, LOU Decheng1, GAO Zhanjun4, LIU Lei1, LIANG Hongmei1, WANG Qingfeng1, LI Qiang1,3 & MA Mingzhen1,2.1. Key Laboratory of Metastable Materials Science & technology of Hebei, Yanshan University, Qinhuangdao 066004, china 2. National Key Laboratory for Precision Hot Processing of Metals, Harbin {2. of technology, Harbin 150001, china 3. College of Mechanical engineering, Yanshan University, Qinhuangdao 066004, china 4. Chinese Academy of engineering, Beijing 100038, china 1. Key Laboratory of Metastable Materials Science & technology of Hebei Yanshan University 066004 Qinhuangdao China 2. College of Mechanical engineering Yanshan University 066004 Qinhuangdao China 3. Chinese Academy of engineering 100038 Beijing China 4. National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology 150001 Harbin China

Mechanical properties of the Zr41Ti14Cu12.5Ni10Be2..5 bulk amorphous alloy at different temperatures were investigated. The compression test was carried out on a Gleebe-32.0 machine at 345 and 375°C, respectively, in the supercooled liquid region. It is shown that decreasing the compressive rate and increasing temperature have a similar influence trend on the compressive behavior of the bulk amorphous alloy. Room and low temperature tensile strengths were tested on the Instron materials testing system. At low temperature, the tensile strength decreased with decreasing of the testing temperature. Hardness measurement indicated that below the glass transition temperature, the hardness decreased with increasing of the annealing temperature and duration time. It, however, increased when the annealing treatment was performed above the glass transition temperature.

关键词： Zr41Ti14Cu12.5Ni10Be2..5 bulk amorphous alloy, mechanical properties, compressive deformation.

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Investigation of ZSM-5/MCM-41 Composite Molecular Sieve for Reducing Olefin Content of FCC Gasoline

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china Petroleum Processing & Petrochemical technology 2009年第4期11卷 10-17页

作者： Ji Dekun~(1,2. Li Shuyuan~1 Ding Fuchen~2.Chi Yaoling~2.(1.Chemical engineering School,china University of Petroleum(Beijing),Beijing 102.49 2.{2. of Chemical engineering,Beijing institute of Petrochemical technology) Chemical engineering School China University of Petroleum (Beijing) Beijing 102249 China department of Chemical engineering Beijing Institute of Petrochemical Technology China

ZSM-5/MCM-41 composite molecular sieve was prepared by the nano-assembling *** ZSM-5 molecular sieve,the MCM-41 molecular sieve,the ZSM-5/MCM-41 mechanical mixture and the ZSM-5/MCM-41 composite molecular sieve were characterized by X-ray powder diffractometry,N_2.adsorption isotherms,temperature programmed desorption of ammonia and scanning electron microscopy and their properties were *** FCC gasoline as the feed,activities of different molecular sieves for reducing olefin content were investigated in a continuous high-pressure micro-reactor unit under the following conditions:a reaction temperature of 400℃,a reaction time of 2.h,a weight hourly space velocity of 3h^(-1),and a reaction pressure of 2.0 *** results showed that the HMCM-41 molecular sieve had low reaction performance,and the HZSM-5 molecular sieve demonstrated high aromatization activity,while the ZSM-5/MCM- 41 composite molecular sieve exhibited a best olefin-reducing performance because of its high isomerization activity and moderate aromatization *** a largest olefin-reducmg capability and a reasonable distribution of products,the composite molecular sieve was more suitable for FCC gasoline upgrading compared to other three catalysts.

关键词： ZSM-5 MCM-41 composite molecular sieve FCC gasoline olefin reduction

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Complete quantum circuit of Haar wavelet based MRA

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Chinese Science Bulletin 2005年第16期50卷 1796-1798页

作者： HE Yuguo1,2.& SUN Jigui1,3 1. College of Computer Science and technology, Jilin University, Changchun 130012. china 2. {2. of Computer Science and engineering, Beijing institute of technology, Beijing 100081, china 3. Key Laboratory of Computation and Knowledge engineering of Min-istry of Education, Jilin University, Changchun 130012. china College of Computer Science and technology Jilin University Changchun 130012 China

Wavelet analysis has applications in many ar- eas, such as signal analysis and image processing. We pro- pose a method for generating the complete circuit of Haar wavelet based MRA by factoring butterfly matrices and con- ditional perfect shuffle permutation matrices. The factoriza- tion of butterfly matrices is the essential part of the design. As a result, it is the key point to obtain the circuits of I 2. ⊕ W ⊕ I 2. ? 2. ?2. In this paper, we use a simple means to de- velop quantum circuits for this kind of matrices. Similarly, the conditional permutation matrix is implemented entirely, combined with the scheme of Fijany and Williams. The cir- cuits and the ideas adopted in the design are simple and in- telligible.

关键词：量子计算量子算法量子电路 Haar微波 MRA

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Asynchronous double-precision windows based unmanned aerial vehicle real-time path planning

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Science china(Information Sciences) 2010年第2期53卷 215-222页

作者： REN Min 1 & HUO XiaoHua 2.1 College of Mechatronic engineering and Automation, National University of Defense technology, Changsha 410073,{2. 2.communication institute, Equipment Academy of Air Force, Beijing 100085,{2. 1. College of Mechatronic engineering and Automation National University of Defense Technology Changsha 410073 China2. Communication Institute Equipment Academy of Air Force Beijing 100085 China

A real-time path planning approach based on asynchronous double-precision windows is proposed for unmanned aerial vehicles (UAVs). In this proposed method, cursory paths and elaborate paths are planned respectively in the global and local windows. Specifically, global cursory path planner and local elaborate path planner are integrated by rolling two windows on different frequencies with different modes. Simulation results demonstrate that the proposed approach is effective for realizing a balance between the optimality and the time efficiency of online path planning by adapting the range of windows and the precision of samples.

关键词： unmanned aerial vehicle (UAV) path planning rolling optimizing asynchronous double-precision windows

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Electronic structure and magnetism of R(Fe,Si)_(12. (R=Y,Nd)

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2. FAN Zhijian1, GAO Tao3 & QI Xinhua31. institute of Nuclear Physics and Chemistry, china Academy of {2. Physics, Mianyang 62.900, china 2. department of physics, Peking university, Beijing 100871, china 3. institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, china 1. institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China 2. department of physics Peking university Beijing 100871 China 3. institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12.compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2.(R = Y, Nd) are larger than those of RFe10M2.(M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12.R = Y Nd) magnetic moment Density of state.

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Growth of Carbon Encapsulated Long Nickel Nanorods on Bulk Nickel Substrate

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Journal of Wuhan University of technology(Materials Science) 2011年第1期26卷 28-32页

作者：宾晓蓓 College of Resources & Environment engineering Wuhan University of Technology

Carbon nanotube encapsulated nickel nanorods were catalytic grown via pyrolysis of oil on a bulk nickel wire substrate. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy were employed to characterize the as-prepared sample. The results show that, carbon nanotubes possess several microns in length, the filled metallic nickel nanorods with a uniform diameter of 35 nm were tightly encapsulated by the carbon capsules. The detailed formation mechanism for the carbon nanotubes encapsulated nickel nanorods were discussed briefly.

关键词： carbon nanotube nickel nanorod pyrolysis core-shell

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