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The Design of Lens Imaging System byMeans of Fractional Fourier Transform

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Chinese Journal of Lasers 2002年第2期11卷 27-32页

作者： CHeN Jiannong XU Qiang (department of Physics, Yantai Teachers’ university, Yantai 264025, China)D.R.Selviah(department of electronic and electrical engineering, university college london, Torrington Place, london wc1e 7je, uk) department of Physics Yantai Teachers' University Yantai 264025 department of electronic and electrical engineering University College London Torrington Place 英国 London WC1E 7JE

The relation between the 2nd fractional Fourier transform and the imaging process of an optical system is discussed. By changing the coordinate scales of the input plane in respect to the magnification of the optical imaging system, the fractional Fourier transform can be a powerful tool in designing specific imaging system. The Gaussian imaging formula of single lens is obtained by using the tool. Finally the procedures are generalized for designing a double-lens imaging system through an example.

关键词： lens imaging system fractional Fourier transform Gaussian imaging formula

Repetitive learning control of nonlinear systems over finite intervals

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Science China(Information Sciences) 2010年第1期53卷 115-128页

作者： SUN MingXuan1, WANG DanWei2 & CHeN PengNian3 1college of Information engineering, Zhejiang university of Technology, Hangzhou 310014, China 2School of electrical and electronic engineering, Nanyang Technological university, Singapore 639794 3department of Mathematics, China Institute of Metrology, Hangzhou 310018, China 1. college of Information engineering Zhejiang University of Technology Hangzhou 310014 China2. School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639794 Singapore3. Department of Mathematics China Institute of Metrology Hangzhou 310018 China

Iterative learning control requires initial repositioning, while the time functions to be learned should be of periodicity in repetitive control. However, there are cases in practice where the time-varying unknowns are not periodic but repetitive, and repetitive learning control is applicable with avoidance of initial repositioning. In this paper, repetitive learning control designs are presented for a broader class of nonlinear systems over finite intervals. The Freeman formula is modified and used for stabilization of the nominal nonlinear time-varying system undertaken. The global stability of the learning system and asymptotic convergence of the tracking error are established through analysis of both partially and fully saturated learning algorithms, respectively. The repetitive learning control method is theoretically shown to be effective in dealing with time-varying parametric uncertainties.

关键词： Initial condition problem convergence iterative learning control repetitive control repetitive learning control nonlinear systems

Influence of modulation ratio on structure and properties of nanoscale ZrB_2/ZrAlN multilayered coatings

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Science China(Technological Sciences) 2010年第3期53卷 772-775页

作者： LI DeJun 1,KANG YuanBin 1,DONG Lei 1,DeNG XiangYun 1,LIU Hao 2 &SUN XueLiang 2 1college of Physics and electronic Information Science,Tianjin Normal university,Tianjin 300387,China 2 department of Mechanical&Materials engineering,university of Western Ontario,london ON,Canada 1. college of Physics and electronic Information Science Tianjin Normal University Tianjin 300387 China2. Department of Mechanical & Materials Engineering University of Western Ontario London ON Canada

ZrB2/ZrAlN multilayered coatings with various modulation ratios(t ZrB2:t ZrAlN)and constant modulation periods were prepared by magnetron sputtering system at room ***,XRD,surface profiler and nano-indenter were employed to investigate the influences of tZ rB 2:tZrAlNon the microstructure and mechanical properties of the *** interfaces and nanoscale multilayered modulation were confirmed by *** multilayer with modulation period of 40 nm and ratio of 3:1 displayed the highest hardness(36.4 GPa)and critical fracture load(76.477 mN)with lower *** polycrystalline structure and multilayered modulate structure were directly responsible for the enhanced mechanical properties.

关键词： ZrB2/ZrAlN multilayered coating magnetron sputtering modulation ratio nanoscale

Adsorption and adhesion of blood proteins and fibroblasts on multi-wall carbon nanotubes

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Science China(Life Sciences) 2009年第5期52卷 479-482页

作者： LI DeJun1, YUAN Li1, YANG Ying1, DeNG XiangYun1, Lü XiaoYing2, HUANG Yan2, CAO Zheng2, LIU Hao3 & SUN XueLiang3 1 college of Physics and electronic Information Science, Tianjin Normal university, Tianjin 300074, China 2 State Key Laboratory of Bioelectronics, Southeast university, Nanjing 210096, China 3 department of Mechanical & Materials engineering, university of Western Ontario, london, ON, Canada college of Physics and electronic Information Science Tianjin Normal University Tianjin 300074 China State Key Laboratory of Bioelectronics Southeast University Nanjing 210096 China department of Mechanical & Materials engineering University of Western Ontario London ON Canada

This article concerns the investigation of blood protein adsorption on carbon paper and multi-wall carbon nanotubes (MwcNTs). Mouse fibroblast cell adhesion and growth on MwcNTs was also studied. The results showed that fibrinogen adsorption on carbon paper was much lower than that on MwcNTs, which means that platelets readily aggregate on the surface of MwcNTs. Mouse fibroblast cells implanted on MwcNTs tended to grow more prolifically than those implanted on carbon paper. The cell concentration observed on MwcNTs increased from 1.2×105/mL for a single day culture to 2×105/mL for a 7-day culture. No toxicity reaction was observed during the culturing period. These results indicated that MwcNTs possessed excellent tissue compatibility.

关键词： multi-wall carbon nanotubes cell adhesion protein adsorption toxicity tissue compatibility

Dynamic scheduling model of computing resource based on MAS cooperation mechanism

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Science in China(Series F) 2009年第8期52卷 1302-1320页

作者： JIANG WeiJin1,2, ZHANG LianMei3 & WANG Pu4 1 School of Computer and electronic engineering, Hunan university of Commerce, Changsha 410205, China 2 School of Information engineering, Xiangtan university, Xiangtan 411000, China 3 electrical engineering college, Wuhan university, Wuhan 430072, China 4 School of Commerce, Central South university, Changsha 410083, China 1. School of Computer and electronic engineering Hunan University of Commerce Changsha 410205 China 2. School of Information engineering Xiangtan University Xiangtan 411000 China 3. electrical engineering college Wuhan University Wuhan 430072 China 4. School of Commerce Central South University Changsha 410083 China

Allocation of grid resources aims at improving resource utility and grid application performance. Currently, the algorithms proposed for this purpose do not fit well the autonomic, dynamic, distributive and heterogeneous features of the grid environment. According to MAS （multi-agent system） cooperation mechanism and market bidding game rules, a model of allocating allocation of grid resources based on market economy is introduced to reveal the relationship between supply and demand. This model can make good use of the studying and negotiating ability of consumers＇ agent and takes full consideration of the consumer＇s behavior, thus rendering the application and allocation of resource of the consumers rational and valid. In the meantime, the utility function of consumer is given; the existence and the uniqueness of Nash equilibrium point in the resource allocation game and the Nash equilibrium solution are discussed. A dynamic game algorithm of allocating grid resources is designed. experimental results demonstrate that this algorithm diminishes effectively the unnecessary latency, improves significantly the smoothness of response time, the ratio of throughput and resource utility, thus rendering the supply and demand of the whole grid resource reasonable and the overall grid load balanceable.

关键词： multi-agent system (MAS) resource scheduling model evolutionary game cooperation mechanism utility function

Terahertz radiation sources based on free electron lasers and their applications

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Science China(Information Sciences) 2012年第1期55卷 1-15页

作者： TAN Ping1,HUANG Jiang2,LIU KaiFeng2,XIONG YongQian2&FAN MingWu1,2 1department of electronic and Information engineering,Huazhong university of Science and Technology,Wuhan 430074,China 2college of electrical and electronic engineering,State Key Laboratory of Advanced electromagnetic engineering and Technology,Huazhong university of Science and Technology,Wuhan 430074,China 1. department of electronic and Information engineering Huazhong University of Science and Technology Wuhan 430074 China2. College of Electrical and Electronic Engineering State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan 430074 China

The tunability,high power and flexible picoseconds-pulse time structure of terahertz(THz)radiation make the THz free-electron laser(FeL)a very attractive THz source of coherent *** paper focuses on the development and perspectives of THz radiation sources based on the *** principles of the low gain THz FeL oscillator,the SASe THz FeL amplifier and the supperradiant THz FeL are reviewed briefly,and the key technologies of THz FeL,such as injector,accelerator,undulator and optical cavity,are discussed,*** current status of and future prospects for THz radiation sources based on the FeL are emphasized in this *** research and development have shown bright future in free-electron laser(FeL)THz radiation *** potential applications can be carried out in the field of imaging,material research,biology medicine,communication,diagnostics and many others.

关键词： terahertz source terahertz applications free electron laser

Approximately optimal tracking control for discrete time-delay systems with disturbances

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Progress in Natural Science:Materials International 2008年第2期18卷 225-231页

作者： Gongyou Tang a,,Huiying Sun b,Haiping Pang c a college of Information Science and engineering,Ocean university of China,Qingdao 266100,China b college of Information and electrical engineering,Shandong university of Science and Technology,Qingdao 266510,China c college of Automation and electronic engineering,Qingdao university of Science and Technology,Qingdao 266042,China college of Information Science and engineering Ocean University of China Qingdao 266100 China college of Information and electrical engineering Shandong University of Science and Technology Qingdao 266510 China college of Automation and electronic engineering Qingdao University of Science and Technology Qingdao 266042 China

Optimal tracking control (OTC) for discrete time-delay systems affected by persistent disturbances with quadratic performance index is considered. By introducing a sensitivity parameter,the original OTC problem is transformed into a series of two-point boundary value (TPBV) problems without time-advance or time-delay terms. The obtained OTC law consists of analytic feedforward and feedback terms and a compensation term which is the sum of an infinite series of adjoint vectors. The analytic feedforward and feedback terms can be found by solving a Riccati matrix equation and two Stein matrix equations. The compensation term can be obtained by using an iteration formula of the adjoint vectors. Observers are constructed to make the approximate OTC law physically realizable. A simulation example shows that the approximate approach is effective in tracking the reference input and robust with respect to exogenous persistent disturbances.

关键词： Discrete systems Time-delay systems Disturbances Optimal control Tracking control

HIGH-INTeNSITY SOURCeS OF UV AND VUV eXCIMeR RADIATION FOR RAPID OXIDATION OF SILICON

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HIGH-INTENSITY SOURCES OF UV AND VUV EXCIMER RADIATION FOR R...

ROBUSTNeSS ANALYSIS OF LeADeR-FOLLOWeR CONSeNSUS

第8届国际材联电子材料国际研讨会

作者： Q. Fang Jun-Ying Zhang Ian W Boyd Dept. of electronic & electrical eng. Univ. college london Torrington Place london wc1e 7je United Kingdom uk Institute of Solid State Physics Chinese Academy of Science Hefei China. Structure Research Laboratory university of Science and Technology of China Hefei 230026 China.

＜正＞ In previous work, we have reported that photo-oxidation of silicon and silicon germanium has been investigated by using ultraviolet （UV） and vacuum ultraviolet （VUV） radiation generated by decaying excimer complexes. Here the principles and oxidation mechanisms on silicon surface by the new generation of UV and VUV radiation and effect of the process parameters are discussed. The photo-oxidation rate of silicon has been found that that depends upon various factors such as wavelength, power density, and exposure-time

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来源： cnki会议评论

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Journal of Systems Science & Complexity 2009年第2期22卷 186-206页

作者： Jinzhi WANG Ying TAN · Iven MAReeLS State Key Laboratory for Turbulence and Complex System and department of Mechanics and Aerospace engi-neering College of Engineering Peking University Beijing 100871 China. Departmen~ of electrical and electronic engineering University of Melbourne Melbourne VIC. 3010 Aus-tralia.

In this paper,robustness properties of the leader-follower consensus are *** of presentation,the attention is focused on a group of continuous-time first-order dynamicagents with a time-invariant communication topology in the presence of communication *** orderto evaluate the robustness of leader-follower consensus,two robustness measures are proposed:the L_2gain of the error vector to the state of the network and the worst case L_2 gain at a *** L_2 gain of the error vector to the state of the network is widely used in robust control design andanalysis,the worst case L_2 gain at a node is less conservative with respect to the number of nodes inthe *** is thus suggested that the worst case L_2 gain at a node is used when the robustnessof consensus is *** analysis and simulation results show that these two measuresare sensitive to the communication *** general,the 'optimal' communication topology thatcan achieve most robust performance with respect to either of the proposed robustness measures isdifficult to characterize and/or *** the in-degree of each follower is one,it is shown thatboth measures reach a minimum when the leader can communicate to each node in the network.

关键词： Communication errors leader-follower consensus robustness.