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Chaotic Dynamics of Monotone Twist Maps

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Acta Mathematica Sinica,English Series 2022年第1期38卷 179-204页

作者： guo wei YU Chern Institute of Mathematics and LPMC Nankai UniversityTianjin 300071P.R.China

For a monotone twist map,under certain non-degenerate condition,we showed the existence of infinitely many homoclinic and heteroclinic orbits between two periodic neighboring minimal orbits with the same rotation number,which indicates chaotic *** results also apply to geodesics of smooth Riemannian metrics on the two-dimension torus.

关键词： Monotone twist maps homoclinic and heteroclinic orbits topological entropy

Local prediction of the chaotic fh-code based on LS-SVM

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Journal of Systems Engineering and Electronics 2008年第1期19卷 65-70页

作者： Wang Yi guo wei National Key Lab of Communication Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

Support vector machine （SVM） is powerful to solve some problems such as nonlinear classification, function estimation and density estimation. To consider the chaotic fh （frequency hopping）-code＇s characters in chaotic dynamic system, the forecasting model of the support vector machine in combination with Takens＇ delay coordinate phase reconstruction of chaotic times is established and the least squares model for large-scale problems is used in local training for this model. Finally, a fh-code series generated by Logistic-Kent mapping is applied to verify the local prediction model. Simulation results show that the high accuracy and fault tolerant SVM model has an excellent performance in predicting the fh code, with a very low mean square error and a high relative coefficient.

关键词： support vector machine(SVM) fh code least squares(LS) prediction

Base mediated direct C–H amination for pyrimidines synthesis from amidines and cinnamaldehydes using oxygen as green oxidants

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Chinese Chemical Letters 2016年第1期27卷 47-50页

作者： wei guo School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 China Key Laboratory of Organo-pharmaceutical Chemistry ofJiangxi Province Gannan Normal University Ganzhou 341000 China

A direct metal-free C-H amination reaction of cinnamaldehydes and amidines to realize the synthesis of polysubstituted pyrimidines was developed in the presence of base. This greener synthetic methodology provides a straightforward approach to the synthesis of a variety of pyrimidine derivatives under mild reaction condition using oxygen as sole oxidants.

关键词： C-H amination Pyrimidines Amidines Cinnamaldehydes Oxygen

Rigidity Theorem of Hypersurfaces with Constant Scalar Curvature in a Unit Sphere

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Acta Mathematica Sinica,English Series 2007年第6期23卷 1075-1082页

作者： guo Xin wei Department of Mathematical Sciences Tsinghua University Beijing 100084 P. R. China

In this paper, we give a characterization of tori S^1 （ √ nr＋2-n/nr）×S^n-1（√ n-2/nr） and S^m （ √n/m ） ×S^n-m （√n-m/n）. Our result extends the result due to Li （1996）on the condition that M is an n-dimensional complete hypersurface in Sn＋1 with two distinct principal curvatures. Keywords principal curvature, Clifford torus, Gauss equations

关键词： principal curvature Clifford torus Gauss equations

Abnormal Growth of Goss Grains in Grain-oriented Electrical Steels

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Journal of Materials Science & Technology 2010年第8期26卷 759-762页

作者： wei guo weimin Mao Department of Materials University of Science and Technology Beijing Beijing 100083 China State Key Laboratory of Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

With the help of electron back scattering diffraction techniques and field emission microscope, the misorienta- tion and the precipitation environment of Goss grains in conventional grain-oriented steel were observed and investigated at the initial stage of secondary recrystallization. It reveals that the abnormal Goss grains have a high fraction of high angle boundaries ranging from 25 to 40 deg. The most important observation is that some of {110}〈001〉 grains in matrix indicated higher particle density than their neighbor grains during final annealing at 875℃ before secondary recrystallization, which could create a favorable environment for their abnormal grain growth. Based on misorientation and precipitation results, the abnormal growth mechanism of Goss grains was sketched.

关键词： Recrystallization Precipitates Goss grain Abnormal grain growth Grain-oriented electrical steel

Backstepping Approach to the Adaptive Regulator Design for a One-Dimensional Wave Equation with General Input Harmonic Disturbance

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Journal of Systems Science & Complexity 2017年第2期30卷 253-279页

作者： guo wei SHAO Zhi-Chao Department of Applied Mathematics School of StatisticsUniversity of International Business and EconomicsBeijing 100029China

This paper considers the parameter estimation and stabilization of an unstable one-dimen- sional wave equation with matched general harmonic disturbance at the controlled end. The back- stepping method for infinite-dimensional system is adopted in the design of the adaptive regulator. It is shown that the resulting closed-loop system is asymptotically stable. Meanwhile, the estimated parameter is shown to be convergent to the unknown parameter as time unes tn ~n^nitv

关键词： Backstepping method distributed parameter system disturbance rejection stability.

Regulation of p53 acetylation

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Science China(Life Sciences) 2017年第3期60卷 321-323页

作者： wei-guo Zhu Department of Biochemistry and Molecular Biology Peking University School of Medical SciencesBeijing 100871China Department of medicine Shenzhen UniversityShenzhen 518060China

As a＂genomic guardian＂,the tumor suppressor p53 plays key roles in maintaining homeostasis under physiological conditions and defending against tumorigenesis upon cellular exposure to internal or external stresses.

关键词： p53 乙酰化肿瘤抑制基因抗肿瘤作用体内平衡生理条件基因组细胞

Configuration Synthesis and Grasping Performance Analysis of Multi-Loop Coupling Capture Mechanism for Launch and Recovery of Torpedo-Shaped Autonomous Underwater Vehicle

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China Ocean Engineering 2024年第3期38卷 453-466页

作者： ZHANG guo-xing XIA Xin-lu guo Jin-wei School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling capture mechanism with strong adaptability and high retraction rate has been proposed for the launch and recovery of torpedo-shaped AUVs with different morphological ***,the principle of capturing motion retraction is described based on the appearance characteristics of torpedo-shaped AUVs,and the configuration synthesis of the capture mechanism is carried out using the method of constrained chain ***,the screw theory is employed to analyze the degree of freedom(DoF)of the capture ***,the 3D model of the capture mechanism is established,and the kinematics and dynamics simulations are carried *** with the capture orientation requirements of the capture mechanism,the statics and vibration characteristics analyses are carried ***,considering the capture process and the underwater working environment,the motion characteristics and hydraulics characteristics of the capture mechanism are ***,a principle prototype is developed and the torpedo-shaped AUVs capture experiment is *** work provides technical reserves for the research and development of AUV capture special equipment.

关键词： capture mechanism torpedo-shaped AUVs configuration synthesis launch and recovery grasping performance analysis

Hypoxic preconditioning in an autohypoxic animal model

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Neuroscience Bulletin 2012年第3期28卷 316-320页

作者： guo Shao guo-wei Lu Medical School Lishui UniversityLishui 323000China Institute for Hypoxia Medicine Department of NeurobiologyCapital Medical UniversityBeijing 100069China School of Basic Medical Sciences Department of NeurobiologyCapital Medical UniversityBeijing 100069China Biomedicine Research Center and Basic Medical College Baotou Medical CollegeBaotou 014030China

Hypoxic preconditioning refers to the exposure of organisms, systems, organs, tissues or cells to moderate hypoxia/ischemia that results in increased resistance to a subsequent episode of severe hypoxia/ischemia. In this article, we review recent research based on a mouse model of repeated exposure to autohypoxia. Pre-exposure markedly increases the tolerance to or protection against hypoxic insult, and preserves the cellular structure of the brain. Furthermore, the hippocampal activity amplitude and frequency of electroencephalogram, latency of cortical somatosensory-evoked potential and spinal somatosensory-evoked potential progressively decrease, while spatial learning and memory improve. In the brain, detrimental neurochemicals such as free radicals are down-regulated, while beneficial ones such as adenosine are up-regulated. Also, antihypoxia factor（s） and gene（s） are activated. We propose that the tolerance and protective effects depend on energy conservation and plasticity triggered by exposure to hypoxia via oxygen-sensing transduction pathways and hypoxia-inducible factor-initiated cascades. A potential path for further research is the development of devices and pharma-ceuticals acting on antihypoxia factor（s） and gene（s） for the prevention and treatment of hypoxia and related syndromes.

关键词： hypoxia hypoxic preconditioning adaptive medicine