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Adaptive dynamic surface control of NSVs with input saturation using a disturbance observer

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Chinese Journal of Aeronautics 2015年第3期28卷 853-864页

作者： Chen Mou yu jing College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Abstract An adaptive dynamic surface control （DSC） scheme is proposed for the multiinput and multioutput （MIMO） attitude motion of nearspace vehicles （NSVs） in the presence of external dis turbance, system uncertainty and input saturation. The external disturbance and the system uncer tainty are efficiently tackled using a Nussbaum disturbance observer （NDO）, and the adaptive controller is constructed by combining the dynamic surface control technique to handle the problem of ＂explosion of complexity＂ inherent in the conventional backstepping methodl For handling the input saturation, an auxiliary system is designed with the same order as that of the studied MIMO attitude system. Using the error between the saturation input and the desired control input as the input of the designed auxiliary system, a series of signals are generated to compensate for the effect of the saturation in the dynamic surface control design. It is proved that the developed control scheme can guarantee that all signals of the closedloop control system are semiglobally uniformly bounded. Finally, simulation results illustrate that the proposed control scheme can achieve satis factory tracking performance under the composite effects of the input saturation and the external disturbance.

关键词： Auxiliary system Disturbance observer Dynamic surface controlInput saturation Near-space vehicle

定向电场下W_(6)C_(6)团簇的超卤素调制及非线性光学特性

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原子与分子物理学报 2025年第3期42卷 72-76页

作者：蔡璧钧段宇静魏强重庆理工大学理学院重庆400050

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且... 详细信息

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且在特定强度下,OEEF可以将W_(6)C_(6)团簇转变为超卤素.通过对EA值的非线性拟合可以实现对W_(6)C_(6)团簇的连续调制.进一步对不同外电场下W_(6)C_(6)团簇的最高占据分子轨道(HOMO)和最低未占据分子轨道(LUMO)能级进行分析,发现OEEF降低了W_(6)C_(6)团簇LUMO能级是其EA值增大的主因.此外,OEEF可以显著增大W_(6)C_(6)团簇的平均极化率和第一超极化率,尤其是第一超极化率,改变其非线性光学性质.

关键词：定向外电场超原子密度泛函理论 NLO W_(6)C_(6)团簇

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A new sesquiterpene trilactone from the roots of Ginkgo biloba

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Chinese Chemical Letters 2009年第10期20卷 1224-1226页

作者： Ping yu jing yu Liang Department of Natural Medicinal Chemistry China Pharmaceutical University Nanjing 210009 China

A new sesquiterpene trilactone, named bilobanol （1）, along with four known terpene trilactones （ginkgolide A, B, C and bilobalide） were isolated from the roots of Ginkgo biloba collected in Jiangsu Province, China... 详细信息

关键词： Ginkgo biloba Sesquiterpene trilactone Bilobanol

Compatibility and Schur Complements of Operators on Hilbert C~*-Module

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Chinese Annals of Mathematics,Series B 2011年第1期32卷 69-88页

作者： Xiaochun FANG jing yu Department of Mathematics Tongji University Shanghai 200092 China Department of Mathematics Qingdao University Qingdao 266071 Shandong China

Let E be a Hilbert C＊-module,and Y be an orthogonally complemented closed submodule of *** authors generalize the definitions of Y-complementability and Y-compatibility for general（adjointable） operators from Hilbert space to Hilbert C＊-module,and discuss the relationship between each *** equivalent statements about Y-complementability and Y-compatibility,and several representations of Schur complements of Y-complementable operators（especially,of Y-compatible operators and of positive Y-compatible operators） on a Hilbert C＊-module are *** addition,the quotient property for Schur complements of matrices is generalized to the quotient property for Schur complements of Y-complementable operators and Y＊-complementable operators on a Hilbert C＊-module.

关键词： Hilbert C*-module Compatibility Complementability Schur complement Quotient property

Binary Nonlinearization of the Nonlinear Schr?dinger Equation Under an Implicit Symmetry Constraint

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Acta Mathematicae Applicatae Sinica 2014年第2期30卷 379-388页

作者： jing yu jing-song HE Yi CHENG School of Science Hangzhou Dianzi University Department of Mathematics University of Science and Technology of China School of Science Ningbo University

By modifying the procedure of binary nonlinearization for the AKNS spectral problem and its adjoint spectral problem under an implicit symmetry constraint, we obtain a finite dimensional system from the Lax pair of th... 详细信息

关键词： an implicit symmetry constraint binary nonlinearization AKNS system completely integrable Hamiltonian system

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On P-sober Spaces

Acta Mathematica Sinica,English Series 2023年第9期39卷 1768-1780页

作者： yu jing Zhang Bin Zhao School of Mathematics and Statistics Shaanxi Normal UniversityXi’an710119P.R.China

In this paper,we focus on p-sober spaces and prove that(1)the To space X is p-sober if and only if the Smyth power space of X is p-sober;(2)the space X has a p-sober dcpo model if and only if X is T_(1)and p-sober;(3)every non-p-sober T_(0)space does not have a p-sobrification;(4)the T_(0)space X is sober if and only if X is p-sober and PD.

关键词： P-sober dcpo poset model of topological space p-sobrification

Anti-plane problem of four edge cracks emanating from a square hole in piezoelectric solids

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Chinese Journal of Aeronautics 2017年第1期30卷 461-468页

作者： Fan Shiwang Guo Junhong yu jing School of Science Inner Mongolia University of Technology College of General Education Inner Mongolia Normal University

By constructing a new numerical conformal mapping and using the Stroh-type formulism, an anti-plane problem of four edge cracks emanating from a square hole in piezoelectric solids is investigated. The explicit expressions of the complex potential function, field intensity factors, energy release rates and mechanical strain energy release rate near the crack tip are obtained under the assumptions that the surfaces of the cracks and hole are electrically permeable and electrically impermeable. Numerical examples are presented to show the influences of the geometrical parameters of defects and applied mechanical/electrical loads on the energy release rate and mechanical strain energy release rate under two electrical boundary conditions.

关键词： Cracks Conformal mapping Hole Piezoelectric material Stroh-type formulism

Complex variable method for an anti-plane elliptical cavity of one-dimensional hexagonal piezoelectric quasicrystals

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Chinese Journal of Aeronautics 2015年第4期28卷 1287-1295页

作者： yu jing Guo Junhong Xing Yongming School of Science Inner Mongolia University of Technology College of General Education Inner Mongolia Normal University

Based on the fundamental equations of piezoelasticity of quasicrystal media, using the symmetry operations of point groups, the linear piezoelasticity behavior of one-dimensional（1D）hexagonal quasicrystals is investigated and the piezoelasticity problem of 1D hexagonal quasicrystals is decomposed into two uncoupled problems, i.e., the classical plane elasticity problem of conventional hexagonal crystals and the phonon–phason-electric coupling elasticity problem of1 D hexagonal *** final governing equations are derived for the phonon–phasonelectric coupling anti-plane elasticity of 1D hexagonal *** complex variable method for an anti-plane elliptical cavity in 1D hexagonal piezoelectric quasicrystals is proposed and the exact solutions of complex potential functions, the stresses and displacements of the phonon and the phason fields, the electric displacements and the electric potential are obtained *** the cavity into a crack, the explicit solutions in closed forms of electro–elastic fields,the field intensity factors and the energy release rate near the crack tip are derived.

关键词： Complex variable methodElliptical cavity Fracture mechanics Piezoelasticity Quasicrystals

Mottness,phase string,and high-T_(c)superconductivity

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Chinese Physics B 2022年第8期31卷 37-47页

作者： jing-yu Zhao Zheng-yu Weng Institute for Advanced Study Tsinghua UniversityBeijing 100084China

It is a great discovery in physics of the twentieth century that the elementary particles in nature are dictated by gauge forces,characterized by a nonintegrable phase factor that an elementary particle of charge q acquires from A to B points:P exp(iq/hc∫A^(B)A_(μ)dxμ),where Aμis the gauge potential and P stands for path *** a many-body system of strongly correlated electrons,if the so-called Mott gap is opened up by interaction,the corresponding Hilbert space will be fundamentally changed.A novel nonintegrable phase factor known as phase-string will appear and replace the conventional Fermi statistics to dictate the low-lying *** by the Mott gap,which is clearly identified in the high-Tc cuprate with a magnitude>1.5 e V,such a singular phase factor can enforce a fractionalization of the electrons,leading to a dual world of exotic elementary particles with a topological gauge structure.A non-Fermi-liquid“parent”state will emerge,in which the gapless Landau quasiparticle is only partially robust around the so-called Fermi arc regions,while the main dynamics are dominated by two types of gapped ***,superconductivity,and a Fermi liquid with full Fermi surface can be regarded as the low-temperature instabilities of this new parent *** numerics and experiments provide direct evidence for such an emergent physics of the Mottness,which lies in the core of a high-Tc superconducting mechanism.

关键词： mechanism of high-T_(c)superconductivity doped Mott insulator emergent organizing principle