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H∞ control of a class of nonlinear Hamiltonian descriptor systems

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science{1.({2. sciences) 2010年第11期53卷 2195-2204页

作者： SUN LiYing1.2.& WANG YuZhen1.1.1. of Control science and {2., shandong University, jinan 2.0061. china 2.0} of science, University of jinan, jinan 2.002., china 1. school of Control {1. and {2. Shandong University Jinan 250061 China2. School of Science University of Jinan Jinan 250022 China

This paper studies the stabilization and H∞ control of a class of nonlinear Hamiltonian descriptor systems. Firstly, based on the structural characteristic of the nonlinear Hamiltonian descriptor system, an equivalent nonlinear dissipative Hamiltonian differential-algebraic system is obtained by using restricted system equivalent theory. With the dissipative form, the stabilization problem is then discussed for the nonlinear Hamiltonian descriptor systems, and an H∞ controller is designed. Finally, simulations on a nonlinear circuit system are given.

关键词： nonlinear Hamiltonian descriptor systems stabilization H∞ control

Adaptive synchronization of neural networks with different attractors

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Progress in Natural science:Materials International 2007年第6期17卷 687-695页

作者： Zhang Huaguang1. Guan Huanxin1.and Wang Zhanshan1.2.1. {1. of information {2. and engineering, Northeastern University, Shenyang 1.0004, china 2. school of information science and engineering, Shenyang Ligong University, Shenyang 1.01.8, china) [a]school of {1. {2. and engineering Northeastern University Shenyang China [b]school of {1. {2. and engineering Shenyang Ligong University Shenyang China

This paper aims to present an adaptive control scheme for the synchronization of two classes of uncertain neural networks with different attractors. A new sufficient condition for the global synchronization of two kinds of neural networks with different attractors is derived. The proposed control method is efficient and easy to be implemented. Numerical simulation is used to show the effectiveness of the obtained result.

关键词： neural networks attractor adaptive synchronization linear matrix inequality.

Repetitious-Hot-Pressing Technique in Hot-Pressing Process

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Journal of Materials science & Technology 2003年第5期19卷 486-488页

作者： Shixue SONG, Xing AI, Wei GAO and Jun ZHAO1.school of Mechanical {1., {2. University, jinan 2.0061. china2.school of science, jinan University, jinan 2.002., china school of Mechanical {1. Shandong University Jinan 250061 China school of {1. Jinan University Jinan 250022 China

A new pressing method was proposed for hot-pressing process. Experimental results indicated that the porosity in Al2.3/TiC/ Ni/Mo (hereafter called AI2.3/TiC composite) composite compacts decreases by 6% after adopting this new technique, compared to traditional hot-pressing technique under the same sintering temperature. The flexural strength and Vicker hardness increase from 883 MPa to 980 MPa and from 1. GPa to 2..1.GPa, respectively. A theoretical model was given to analyze the densification mechanism of the composite in the process of repetitious-hot-pressing.

关键词： Hot-pressing sintering Repetitious-hot-pressing sintering Composite

Synthesis of a novel centipede-like copolymer of styrene and methyl methacrylate

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science{1. Chemistry 2007年第2期50卷 253-257页

作者： LI AiXiang1 & LU ZaiJun2.1 school of Material science and {2.,shandong University of Technology,Zibo 2.5049,china 2.school of Chemistry and Chemical {2.,shandong University,jinan 2.01.0,china 1. school of Material {1. and {2. Shandong University of Technology Zibo 255049 China 2. {1. of Chemistry and Chemical engineering Shandong University Jinan 250100 China

A well-defined,A2.-type,centipede-like copolymer of styrene and methyl methacrylate(PS-PS-PMMA) was synthesized by the combination of living anionic polymerization and atom transfer radical polym-erization(ATRP) . The synthetic approach involves the coupling reaction of polystyrene(PS) backbone bearing 1.1.diphenylethene(DPE) pendant groups,produced by ATRP and Wittig reaction,with living polystyryllithium(PSLi) ,and subsequent polymerization of the resulting 1.1.diphenylmethyl anions with methy methacrylate. The centipede-like copolymer was characterized by 1. NMR,IR,SEC,SLS,and DSC measurements.

关键词： architecture atom transfer radical polymerization centipede-like copolymer coupling reaction living anionic polymerization

The influence of laser pulse on the photoabsorption spectra of Li atom in strong external field

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science{1.(Physics,Mechanics & Astronomy) 2006年第2期49卷 178-186页

作者： WANG Dehua1.& LIN Shenglu2.1. {1. of Physics and Electronic engineering, Yantai Normal University, Yantai 2.402.,{2. 2. Department of Physics, shandong Normal University, jinan 2.001.,{2. 1. school of Physics and Electronic {1. Yantai Normal University Yantai 264025 China 2. Department of Physics Shandong Normal University Jinan 250014 China

Using the time-dependent perturbation theory and the calculation formula of the single- and double-pulse absorption spectra of the atom in strong external fields, we calculate the single- and double-pulse absorption spectra of Li atom in strong magnetic field for different pulse widths. The results show that a pulse of some width can reduce the contribution of the short period closed orbits and eliminate the contribution of the long period orbits. Compared with the single-pulse absorption spectra, we found that for some phase differences, the double-pulse laser absorption spectra are strengthened; while for others, they are reduced. Therefore, we can use the pulse laser to control the oscillation of the absorption spectra and obtain the optimization object.

关键词： laser pulse closed orbit absorption spectra.

Diffusion and Oxidation Wear of PCBN Tool based on Thermodynamics

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Journal of Wuhan University of Technology(Materials science) 2010年第2期25卷 265-271页

作者：邵芳 Binzhou Vacational College school of Mechanical {1. Shandong University

The rules of diffusion wear and oxidation wear for PCBN cutting tools were analyzed based on thermodynamics theory. Dissolution concentrations in typical normal workpice materials of PCBN tool material at different temperature were then calculated. Diffusion reaction rules in high temperature were developed and analyzed using the Gibbs free energy criterion. The machining tests were conducted using the PCBN tools at different cutting speeds of 50, 95,1.0 and 1.0 m/min, feed of 0.1. 0.2.and depth of cut of 0.1. 0.8, 1. and 1.5 mm respectively on a PUMA300LM numerically-controlled lathe. It was found that the theoretical results were uniform with the experimental data, and the results will provide useful references for tool material design and selection.

关键词： thermodynamics PCBN tool diffusion wear oxidation wear

Intermediate processes and critical phenomena: Theory, method and progress of fractional operators and their applications to modern mechanics

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science{1.(Physics,Mechanics & Astronomy) 2006年第3期49卷 257-272页

作者： XU Mingyu1.& TAN Wenchang2.1. Institute of Applied Mathematics, {1. of Math & System science, {2. University, jinan 2.01.0, china 2. State Key Laboratory of Turbulence and Complex Systems & Department of Mechanics and engineering science, Peking University, Beijing 1.0871. china 1. Institute of Applied Mathematics School of Math & System Science Shandong University Jinan 250100 China 2. State Key Laboratory of Turbulence and Complex Systems & Department of Mechanics and {1. science Peking University Beijing 100871 China

From point of view of physics, especially of mechanics, we briefly introduce fractional operators (with emphasis on fractional calculus and fractional differential equa- tions) used for describing intermediate processes and critical phenomena in physics and mechanics, their progress in theory and methods and their applications to modern me- chanics. Some authors’ researches in this area in recent years are included. Finally, prospects and evaluation for this subject are made.

关键词： fractional operators,intermediate processes,critical phenomena,modern mechanics

Adaptive bidirectional diffusion for image restoration

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science{1.({2. sciences) 2010年第12期53卷 2452-2460页

作者： FU ShuJun 1,2.& ZHANG CaiMing 1 1 school of Computer science and Technology, {2. University, jinan 2.0101, china 2.school of Mathematics, {2. University, jinan 2.01.0, china 1. school of Computer {1. and Technology Shandong University Jinan 250101 China2. School of Mathematics Shandong University Jinan 250100 China

A large number of applications in image processing and computer vision depend on image quality. In this paper, combining the forward diffusion with the backward diffusion by different weights, we present an adaptive bidirectional diffusion method for image denoising and deblurring simultaneously. Further, we introduce a gradient factor into the data fidelity term, which forms a spatially varying constraint and allows a better restoration of image edges and fine details. In order to obtain a stable solution, we develop a numerically stable scheme and give its theoretical analysis. Finally, we show advantages of this method in deblurring edges, denoising and restoring fine details of image compared with other related methods in experiments.

关键词： image restoration bidirectional diffusion inverse diffusion anisotropic diffusion stabilizing scheme spatially varying constraint

Study on the cluster of floating dross before nucleating during hot-dipping process

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science{1. Chemistry 2005年第1期48卷 83-88页

作者： WEI Yunhe1. ZHANG Changqiao1. QIN Jingyu2.& LIU Chengbu1.1. {1. of Chemistry and Chemical engineering, {2. University, jinan 2.01.0, china 2. The Key Laboratory of Liquid Structure and Heredity of Materials of Ministry of Education, {2. University, jinan 2.0061. china 1. school of Chemistry and Chemical {1. Shandong University 250100 Jinan China 2. The Key Laboratory of Liquid Structure and Heredity of Materials of Ministry of Education Shandong University 250061 Jinan China

During hot-dipping in molten Zn-55Al, the forming of “floating” dross is closely re- lated with the interaction between the Al and the Fe atoms. Utilizing the thita-thita X-ray diffraction and the Percus-Yevick hard sphere model, this paper investigates the structure of molten Al3Fe that is an approximant of partial melt in practical Zn-55Al alloy melt. It is found that in the melt there exist clusters that resemble the structure of intermetallic compound Al3Fe. The strong in- teraction between Al and Fe atoms is also indicated by the deficiency of the coordination number from 1.0}and the shrinkage of averaged atomic diameter. Based on such {1., it is specu- lated that in the molten Zn-55Al, with the accumulation of Fe, Al3Fe-like clusters form with priority, then grow into dross. On the other hand, after deflating of the effective hard sphere diameter of pure Al atom and enlarging that of the pure Fe atom, the modified model can achieve reasonable fit to the experimental structure factor. Hard sphere modeling also gave a good estimation of the mass density 3.65 g/cm3 of liquid Al3Fe alloy at 1.50℃. Compared with the density of 3.7 g/cm3 of Zn-55Al, the reason for dross floating is satisfactorily understood.

关键词： hot-dipping, dross, Al3Fe alloy, molten structure, P-Y model.