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Synchronization of chaos using radial basis functions neural networks

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Journal of Systems Engineering and Electronics 2007年第1期18卷 83-88,100页

作者： ren Haipeng liu Ding School of Automation and Information Engineering Xi'an Univ. of Technology Xi'an 710048 P.R.China

The Radial Basis Functions Neural Network （RBFNN） is used to establish the model of a response system through the input and output data of the system. The synchronization between a drive system and the response system can be implemented by employing the RBFNN model and state feedback control. In this case, the exact mathematical model, which is the precondition for the conventional method, is unnecessary for implementing synchronization. The effect of the model error is investigated and a corresponding theorem is developed. The effect of the parameter perturbations and the measurement noise is investigated through simulations. The simulation results under different conditions show the effectiveness of the method.

关键词： Chaos synchronization Radial basis function neural networks Model error Parameter perturbation Measurement noise.

The Existence of Solutions for the Problem in the Optical Lattice with Nonlocal Nonlinearity

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Acta Mathematicae Applicatae Sinica 2012年第4期28卷 681-690页

作者： Rui-feng ZHANG ren-tao liu Institute of Contemporary Mathematics Henan University College of Mathematics and Information Science Henan University

We address the impact of nonlocality in the physical features exhibited by solitons supported by Kerr-type nonlinear media with an imprinted optical lattice. We discuss the solitons solution for a class of nonlinear SchrSdinger equations in the optical lattice with nonlocal nonlinearity. We also show via a uniform priori estimate that existence and uniqueness of the global solution for the initial problem.

关键词： SchrSdinger equation Cauchy problem contract mapping principle Calerkin method

On the diffuse soft X-ray emission from the nuclear region of M51

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Research in Astronomy and Astrophysics 2015年第12期15卷 2164-2172页

作者： Ji-ren liu Shu-De Mao National Astronomical Observatories Chinese Academy of Sciences Physics Department and Tsinghua Center for Astrophysics Tsinghua University Jodrell Bank Centre for Astrophysics University of Manchester

We present an analysis of the diffuse soft X-ray emission from the nuclear region of M51 combining both XMM-Newton RGS and Chandra data. Most of the RGS spectrum of M51 can be fitted with a thermal model with a temperature of 0.5 keV except for the O vii triplet, which is forbidden-line dominated. The Fe L-shell lines peak around the southern cloud, where the O viii and N vn Lya lines also peak. In contrast, the peak of the O vii forbidden line is about 10＂ offset from that of the other lines, indicating that it is from a spatially distinct component. The spatial distribution of the O vii triplet mapped by the Chandra data shows that most of the O vii triplet flux is located at faint regions near edges, instead of the southern cloud where other lines peak. This distribution of the O vii triplet is inconsistent with the photoionization model. Other mechanisms that could produce the anomalous O vii triplet, including a recombining plasma and charge exchange X-ray emission, are discussed.

关键词： atomic processes -- plasmas -- ISM: jets and outflows -- galaxies:Seyfert -- galaxies: individual: M51 (NGC 5194) -- X-rays: ISM

Biological Stimuli-responsive Polymer Systems:Design,Construction and Controlled Self-assembly

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Chinese Journal of Polymer Science 2018年第3期36卷 347-365页

作者： Miao-Miao Xu ren-Jie liu Qiang Yan Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China

Biological stimuli-responsive polymers have increasingly attracted attention in recent years because it can satisfy many requirements of applications related with human body while traditional systems do not *** to the importance of this burgeoning field,great efforts have been devoted and,up to now,polymer chemists have made a remarkable success in this prospective research *** this review,we systematically generalize the present state of biological stimuli-responsive polymer *** highlight several representative examples to specify the current problems and look ahead a clear sense of direction in this area.

关键词： Biological stimuli Responsive polymer Controlled self-assembly Biomedicine

Synthesis and Properties of IPN Hydrogels Based on Konjac Glucomannan and Poly(acrylic acid)

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Chinese Chemical Letters 2006年第10期17卷 1377-1380页

作者： Bing liu Zhi Lan liu ren Xi ZHUO Key Laboratory of Biomedical Polymers of Ministry of Education Department of Chemistry Wuhan University Wuhan 430072

Novel interpenetrating polymer network （IPN） hydrogels based on konjac glucomannan （KGM） and poly（acrylic acid）（PAA） were prepared by polymerization and cross-linking of acrylic acid （AA） in the pre-fabricated KGM gel. The IPN gel was analyzed by FF-IR. The studies on the equilibrium swelling ratio of IPN hydrogels revealed their sensitive response to environmental pH value. The results of in vitro degradation showed that the IPN hydrogels retain the enzymatic degradation character of KGM.

关键词： Hydrogel interpenetrating polymer network pH-sensitivity konjac glucomannan poly(acrylic acid).

Preparation and Properties of Aqueous SCNTs Dispersion based on A UV-curable Polymeric Dispersant

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Journal of Wuhan University of Technology(Materials Science) 2018年第2期33卷 485-491页

作者：袁妍 WU Haiqiang liu Jingcheng LUO Jing liu ren liu Xiaoya The Key Laboratory of Synthestic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan University

A novel photosensitive copolymer P（SS-co-AA-g-GMA）（PSAG） was synthesized and utilized to noncovalently functionalize pristine single-walled carbon nanotubes（SCNTs）. PSAG was highly effective for the solubilization of SCNTs in water and validated by UV-vis absorption spectra experiments, resulting in homogeneous and stable PSAG-SCNT aqueous dispersion. The microstructure of SCNTs was observed through Raman spectroscopy and transmission electron microscopy. In addition, compared with the two common polymeric dispersants of Triton X-100 and PSS, PSAG demonstrated more effective performances for dispersing SCNTs under identical conditions. Furthermore, the photosensitive PSAG-SCNTs can be crosslinked after UV irradiation, leading to significant improvement in the water resistance of SCNT films. UV-cured films can be transferred to plastic wrap to form a flexible film with high electrical conductivity.

关键词： single-walled carbon nanotubes(SCNTs) polymeric dispersant UV-curable conductive water resistance

Preparation and characteristics of indium tin oxide (ITO) thin films at low temperature by r.f. magnetron sputtering

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Rare Metals 2006年第Z1期25卷 137-140页

作者： ren Bingyan liu Xiaoping WANG Minhua XU Ying School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China Beijing Solar Energy Research Institute Beijing 100083 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China Beijing Solar Energy Research Institute Beijing 100083 China Beijing Solar Energy Research Institute Beijing 100083 China

Low resistivity and highly transparent ITO conducting films for solar cell applications were fabricated at low temperature by r.f. magnetron sputtering. ITO films were deposited on glass and silicon substrate. Electrical, optical, structural and morphological properties of the ITO films were investigated in terms of the preparation conditions. The annealing treatment has improved the properties of the ITO films at different degree. The maximum transmittance of the obtained ITO films in the visible range is over 92%, and the low resistivity for the ITO films are about 3.85×10-4 Ω·cm at 80 ℃, 80 W after annealing.

关键词： ITO r.f. magnetron sputtering low temperature annealing

Classical-Noise-Free Sensing Based on Quantum Correlation Measurement

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Chinese Physics Letters 2021年第1期38卷 3-9页

作者： Ping Wang Chong Chen ren-Bao liu Department of Physics and The Hong Kong Institute of Quantum Information Science and Technology The Chinese University of Hong KongShatinNew TerritoriesHong KongChina

Quantum sensing,using quantum properties of sensors,can enhance resolution,precision,and sensitivity of imaging,spectroscopy,and *** intriguing question is:Can the quantum nature(quantumness)of sensors and targets be exploited to enable schemes that are not possible for classical probes or classical targets?Here we show that measurement of the quantum correlations of a quantum target indeed allows for sensing schemes that have no classical *** a concrete example,in the case that the second-order classical correlation of a quantum target could be totally concealed by non-stationary classical noise,the higher-order quantum correlations can single out a quantum target from the classical noise background,regardless of the spectrum,statistics,or intensity of the *** a classical-noise-free sensing scheme is *** finding suggests that the quantumness of sensors and targets is still to be explored to realize the full potential of quantum *** opportunities include sensitivity beyond classical approaches,non-classical correlations as a new approach to quantum many-body physics,loophole-free tests of the quantum foundation,et cetera.

关键词： quantum totally stationary

Research and development of 780 MPa cold rolling TRIP-aided steel

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 399-406页

作者： Qiang liu Di Tang Hai-tao Jiang ren-dong liu Xiao-yong Tang National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing Beijing 100083 China Researchand Development Center Anshan Iron and Steel （Group） Corp. Anshan 114001 Liaoning China

As an industry-university cooperative project, an experimental research was conducted to develop a new cold-rolled transformation-induced plasticity （TRIP） steel with a tensile strength of 780 MPa and an elongation of 25% under the conditions that some processing parameters were preestablished according to the actual conditions of factory production lines. The optimal heat treatment conditions for obtaining excellent strength-ductility balance, specifically in intercritical annealing temperature and isothermal treatment temperature, were investigated by means of thermal simulation tests. Ultimately the desirable mechanical properties were attained successfully, and the microstructure and retained austenite stability were studied by optical microscopy （OM） and electron back-scattered diffraction （EBSD）. It has been discovered that the sizes of retained austenite grains are generally proportional to the sizes of carbon-clear space （ferrite and bainite） around them, and there is marked selectivity in their transition sequences under stress-strain.

关键词： TRIP steel heat treatment retained austenite stability