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STATE-FEEDBACK ADAPTIVE STABILIZING CONTROL DESIGN FOR A CLASS OF HIGH-ORDER NONLINEAR SYSTEMS WITH UNKNOWN CONTROL COEFFICIENTS

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Journal of Systems Science & Complexity 2007年第3期20卷 350-361页

作者： Zongyao SUN Yungang LIU school of Control Science and Engineering Shandong University Jinan 250061 China.

In this paper, a new approach is successfully addressed to design the state-feedback adaptive stabilizing control law for a class of high-order nonlinear systems in triangular form and with unknown and nonidentical control coefficients, whose stabilizing control has been investigated recently under the knowledge that the lower bounds of the control coefficients are exactly known. In the present paper, without any knowledge of the lower bounds of the control coefficients, based on the adaptive technique and appropriately choosing design parameters, we give the recursive design procedure of the stabilizing control law by utilizing the approach of adding a power integrator together with tuning functions. The state-feedback adaptive control law designed not only preserves the equilibrium at the origin, but also guarantees the global asymptotic stability of the closed-loop states and the uniform boundedness of all the other closed-loop signals.

关键词： Adaptive stabilizing control adding a power integrator high-order nonlinear systems,state-feedback unknown control coefficients.

EFFECT OF COOLED BOUNDARY ON THE TURBULENT STRUCTURE

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Journal of Hydrodynamics 2003年第5期15卷 54-59页

作者： Li Guo xiang, Mao Hua yong, Li Na school of Energy and Power Engineering, shandong university, jinan 250061, china, school of Energy and Power Engineering Shandong University Jinan 250061 China

The flow field in the cooled channel of a heat exchanger was measured usingthe X-type film probes of Hot Wire/Firm Anemotheter, and the turbulent mechanism was discussed. Itis concluded that the airflow is cooled in the flow process, the distribution of the turbulentintensity is relatively convergent near the centcrline and the boundary, the constriction actionproduced due to heat release at the foot of the fins causes u to decrease and w to increase near theroot downstream. It is concluded that the turbulent flow with cooled boundary results from thebalance of production, dissipation and intermittency caused by constriction action.

关键词： heat exchanger cooling turbulent structure

The Tychonoff uniqueness theorem for the G-heat equation

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Science china Mathematics 2011年第3期54卷 463-468页

作者： LIN Qian1,2 1school of Mathematics, shandong university, jinan 250100, china 2 Laboratoire de Mathématiques, CNRS UMR 6205, Université de Bretagne Occidentale, 6, avenue Victor Le Gorgeu, CS 93837, 29238 Brest cedex 3, France 1. school of Mathematics Shandong University Jinan 250100 China2. Laboratoire de Mathématiques CNRS UMR 6205 Université de Bretagne Occidentale 6 avenue Victor Le Gorgeu CS 93837 29238 Brest cedex 3 France

In this paper we shall investigate a uniqueness result for solutions of the G-heat equation. We obtain the Tychonoff uniqueness theorem for the G-heat equation.

关键词： Tychonoff uniqueness theorem G-heat equation G-expectations G-Brownian motion viscosity solutions

ON SOME RESULTS OF YI AND THEIR APPLICATIONS IN THE FUNCTIONAL EQUATIONS

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Acta Mathematica Scientia 2010年第5期30卷 1649-1660页

作者：杨连中张继龙 school of Mathematics and System Sciences Shandong University LMIB and school of Mathematics and System Sciences Beihang University

In this article, we establish some uniqueness theorems that improves some results of H. X. Yi for a family of meromorphic functions, and as applications, we give some results about the non-existence of meromorphic sol... 详细信息

关键词： functional equations meromorphic functions uniqueness

H∞ control of a class of nonlinear Hamiltonian descriptor systems

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Science china(Information Sciences) 2010年第11期53卷 2195-2204页

作者： SUN LiYing1,2 & WANG YuZhen1 1school of Control Science and Engineering, shandong university, jinan 250061, china 2school of Science, university of jinan, jinan 250022, china 1. school of Control Science and Engineering 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

The dynamical properties of Rydberg hydrogen atom near a metal surface

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Science china(physics,Mechanics & Astronomy) 2005年第6期48卷 667-675页

作者： GE Meihua1, ZHANG Yanhui1, WANG Dehua2, DU Mengli3 & LIN Shenglu1 1. College of physics and Electronics, shandong Normal university, jinan 250014, china 2. Department of Mathematics and physics, shandong Institute of Architecture and Engineering, jinan 250014, china 3. Institute of Theoretical physics, Chinese Academy of Sciences, Beijing 100080, china 1. College of physics and Electronics Shandong Normal University 250014 Jinan China 2. Department of Mathematics and physics Shandong Institute of Architecture and Engineering 250014 Jinan China 3. Institute of Theoretical physics Chinese Academy of Sciences 100080 Beijing China

The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion clearly. In this paper we choose the atomic principal quantum number as n = 20. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distance d. When d is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system is integrable. When d becomes smaller, there exists a critical value dc. For d > dc, the system is near-integrable and the motion is regular. While chaotic motion appears for d < dc, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the metal surface.

关键词： Rydberg hydrogen atom, van der Waals interaction, Poincaré surface of section, closed orbit theory, chaos.

Structure of Complex [Ni_2L_2](py)_2(H_2O)_2(L=1,3-Di[o-(o-vanillideneimino) phenoxo]-2-propanol Dianion) with New Nucleating Ligand

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Chinese Chemical Letters 1998年第5期9卷 483-485页

作者： Wen Xing ZHANG Shang Ying LIU Chang Qin MA De Hua JLANG(school of Chemistry, shandong university, jinan 250100) shandong Univ Sch Chem Jinan 250100 Peoples R China

The title dinuclear complex structUre was determined by X-ray diffraction.

关键词： dinuclear Ni (Ⅱ) complex dinucleating Schiff-base ligand structure

Error analysis of the semi-discrete local discontinuous Galerkin method for semiconductor device simulation models

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Science china Mathematics 2010年第12期53卷 3255-3278页

作者： LIU YunXian 1, & SHU Chi-Wang 2 1 school of Mathematics, shandong university, jinan 250100, china 2 Division of Applied Mathematics, Brown university, Providence, RI 02912, USA 1. school of Mathematics Shandong University Jinan 250100 China2. Division of Applied Mathematics Brown University Providence RI 02912 USA

In this paper we continue our effort in Liu-Shu (2004) and Liu-Shu (2007) for developing local discontinuous Galerkin (LDG) finite element methods to discretize moment models in semiconductor device simulations. We consider drift-diffusion (DD) and high-field (HF) models of one-dimensional devices, which involve not only first derivative convection terms but also second derivative diffusion terms, as well as a coupled Poisson potential equation. Error estimates are obtained for both models with smooth solutions. The main technical difficulties in the analysis include the treatment of the inter-element jump terms which arise from the discontinuous nature of the numerical method, the nonlinearity, and the coupling of the models. A simulation is also performed to validate the analysis.

关键词： local discontinuous Galerkin method error estimate semiconductor

MAGNETIC PROPERTIES OF AMORPHOUS CoZr SOFT MAGNETIC FILMS

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Acta Metallurgica Sinica(English Letters) 1990年第9期3卷 176-180页

作者： LIU Yihua shandong university,jinan,chinaYA NG Linqian Huaqiao university,Quanzhou,Fujian,china LIU Yihua Associate Professor,Dept.of physics,shandong university,jinan 250100,china

The amorphous CoZr soft magnetic films with superior properties were prepared by radio-frequency sputtering under pressure of 0.5Pa *** saturation magnetization of the amorphous CoZr films with relation to the Zr content and temperature was *** amorphous CoZr films composed of different constituents obey the Bloch T^(3/2)-low in a wide range of *** number of electrons transferred from each Zr atom to 3d energy band of Co calculated by the rigid band model is about 2.27.

关键词： amorphous alloy radio-frequency sputtering perpendicular anisotropy rigid band model