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Nonlinear Internal Damping of Wave Equations with Variable Coefficients

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Acta Mathematica Sinica,English Series 2004年第6期20卷 1057-1072页

作者： Shao Ji feng De xing feng Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100080P.R.China Institute of Systems Science Academy of Mathematics and Systems ScienceChinese Academy of Sciences

For wave equations with variable coefficients on regions which are not necessarily smooth, we study the energy decay rate when a nonlinear damping is applied on a suitable subrigion.

关键词： Wave equations Energy decay rate Nonlinear internal damping Riemannian manifold

Numbers of Electrons in Solar Flares as Deduced from Microwave and X-Ray Bursts

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Chinese Physics Letters 2001年第3期18卷 455-457页

作者： YU xing-feng YAO Jin-xing Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008 tional Astronomical Observatory Chinese Academy of Sciences

We discuss Whether the numbers of x-ray and radio-produced electrons in solar flares are the *** number of the radio-produced electrons that is estimated with an inhomogeneous source increases by a factor of 10^(3)-10^(4) because of the inhomogeneity and the decreased magnetic field(B=120 G)of the radio *** number of the x-ray-produced electrons decreases by a factor of 10-30 due to the increase of the number density of ions(3 × 10^(10)cm^(-3)).These are the reasons why the number of radio-produced electrons is approximately equal to that of x-ray produced in the 1981 April 27 burst.

关键词： source Solar source

Mapping Analysis of Solar Radio Burst at 17 GHz on 1992 October 27

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Chinese Physics Letters 2000年第8期17卷 621-622页

作者： YU xing-feng YAO Jin-xing Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008 National Astronomical Observatory Chinese Academy of Sciences

The contour maps at 17 GHz on the 1992 October 27 solar burst are *** a nonthermal inhomogeneous model of the radio source,the variations of calculated source size with time are basically consistent with the observation of *** variations of calculated brightness temperature with a distanceρdisplaced from the project center are in better agreement with the observation of map at 01:45:29:889 *** calculation shows that the characterizing magnetic field gradientαB at the peak of 17 GHz is about 2,magnetic strength B is about 737G with the magnetic field Bm of the core being 2000 *** in order to measure the coronal magnetic field accurately,it is necessary to obtain radio-imaging data at more frequencies.

关键词： strength magnetic Solar

FABRICATION AND PROPERTIES OF ANTIFERROELECTRIC RAINBOW ACTUATOR

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Chinese Journal of Mechanical Engineering 2006年第1期19卷 116-119页

作者： SHEN xing feng Wei College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A new type of large-displacement actuator called reduced and internally biased oxide wafer （RAINBOW） is fabricated by chemical reduction of Pb（Sn, Zr, Ti）O3（PSZT） antiferroelectric ceramics and its properties are investigated. It is found that PSZT is easily reduced and the optimal conditions for producing RAINBOW samples are determined to be 870 ℃ for 2-3 h. The antiferroelectrics-ferroelectrics phase transitions occur at lower field strength in RAINBOW actuators compared with normal PSZT actuators. Large axial displacements are also obtained from the RAINBOW actuator by application of electric fields exceeding the phase switching level. However, the field-induced displacement of the RAINBOW actuator is dependent on the manner of applying load on the samples.

关键词： Actuator Reduction Antiferroelectric ceramic Phase switching

Immersed Hypersurfaces in the Unit Sphere S^(m+1) with Constant Blaschke Eigenvalues

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Acta Mathematica Sinica,English Series 2007年第3期23卷 533-548页

作者： xing Xiao LI feng Yun ZHANG Department of Mathematics He'nan Normal University Xinxiang 453007 He'nan P. R. China

For an immersed submanifold x ： M^m→ Sn in the unit sphere S^n without umbilics, an eigenvalue of the Blaschke tensor of x is called a Blaschke eigenvalue of x. It is interesting to determine all hypersurfaces in Sn with constant Blaschke eigenvalues. In this paper, we are able to classify all immersed hypersurfaces in S^m＋1 with vanishing MSbius form and constant Blaschke eigenvalues, in case （1） x has exact two distinct Blaschke eigenvalues, or （2） m = 3. With these classifications, some interesting examples are also presented.

关键词： Moebius form Blaschke eigenvalues Blaschke tensor MSbius metric MSbius second fundamental form

On the Blaschke Isoparametric Hypersurfaces in the Unit Sphere

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Acta Mathematica Sinica,English Series 2009年第4期25卷 657-678页

作者： xing Xiao LI feng Yun ZHANG Department of Mathematics. He'nan Normal University Xinxiang 453007 P. R. China

Given an immersed submanifold x ： M^M → S^n in the unit sphere S^n without umbilics, a Blaschke eigenvalue of x is by definition an eigenvalue of the Blaschke tensor of x. x is called Blaschke isoparametric if its Mobius form vanishes identically and all of its Blaschke eigenvalues are constant. Then the classification of Blaschke isoparametric hypersurfaces is natural and interesting in the MSbius geometry of submanifolds. When n = 4, the corresponding classification theorem was given by the authors. In this paper, we are able to complete the corresponding classification for n = 5. In particular, we shall prove that all the Blaschke isoparametric hypersurfaces in S^5 with more than two distinct Blaschke eigenvalues are necessarily Mobius isoparametric.

关键词： Mobius form Blaschke eigenvalues Blaschke tensor Mobius metric Mobius second fundamental form

An Optimal Control Problem of a Coupled Nonlinear Parabolic Population System

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Acta Mathematicae Applicatae Sinica 2007年第3期23卷 377-388页

作者： Chao-hua Jia De-xing feng Department of Applied Mathematics LMIB of the Ministry of Education Beijing University of Aeronauticsand Astronautics Beijing 100083 China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

An optimal control problem for a coupled nonlinear parabolic population system is considered. The existence and uniqueness of the positive solution for the system is shown by the method of upper and lower solutions. An explicit prior bound of solutions to the system is given by considering an auxiliary coupled linear system. The existence of the optimal control is proved and the characterization of the optimal control is established.

关键词： Nonlinear parabolic systems optimal control upper and lower solutions

Multiregional neural pathway: from movement planning to initiation

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Signal Transduction and Targeted Therapy 2022年第7期7卷 2121-2122页

作者： xing-feng Mao Shuai-shuai Wang feng Han Key Laboratory of Cardiovascular&Cerebrovascular Medicine Drug Target and Drug Discovery CenterSchool of PharmacyNanjing Medical UniversityNanjingChina Gusu School Nanjing Medical UniversitySuzhou Municipal HospitalThe Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhouChina Institute of Brain Science The Affiliated Brain Hospital of Nanjing Medical UniversityNanjingChina

A recent study by Inagaki et *** new evidence that the input from the pedunculopontine nucleus/midbrain reticular nucleus(PPN/MRN)to the thalamus can trigger a rapid switch of ALM activity from a motor planning mode to a motor execution mode.1 Planning and execution are vital components of motor behavior that are produced by distinct patterns of neuronal *** researchers have devoted substantial effort to exploring how the precise neural pathway mediates cuetriggered population activity pattern switching for the execution of planned *** different patterns of neuronal population activity in the motor cortex,thalamus,brainstem,and spinal cord are related to motor planning and execution.2,3 However,to understand how neuronal dynamics in the cortex trigger motor execution,it is essential to explore the mechanism underlying the transition between those different modes in response to contextual Go cues(Fig.1).

关键词： cortex al. execution

Characterization of dwarf mutants and molecular mapping of a dwarf locus in soybean

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Journal of Integrative Agriculture 2016年第10期15卷 2228-2236页

作者： CHENG Wen GAO Jin-shan feng xing-xing SHAO Qun YANG Su-xin feng Xian-zhong Key Laboratory of Systems Biology in Universities of Shandong/College of Life Science Shandong Normal University Key Laboratory of Soybean Molecular Design Breeding Northeast Institute of Geography and Agroecology Chinese Academy of Sciences

Plant height is one of the most important traits in soybean. The semi-dwarf soybean cultivars could improve the ability of lodging resistance to obtain higher yield. To broaden the dwarfism germplasm resources in soybean, 44 dwarf mutants were identified from a gamma rays mutagenized M-2 population. Two of these mutants, Gmdwf1（Glycine max dwarf 1） and Gmdwf2（Glycine max dwarf 2）, were investigated in this study. Genetic analysis showed that both mutants were inherited in a recessive manner and their mutated regions were delimited to a 2.610-Mb region on chromosome 1 by preliminary mapping. Further fine mapping study proved that the two mutants had a common deletion region of 1.552 Mb in the target region, which was located in a novel locus site without being reported previously. The dwarfism of Gmdwf1 could not be rescued by gibberellin（GA） and brassinolide（BR） treatments, which indicated that the biosynthesis of these hormones was not deficient in Gmdwf1.

关键词： soybean dwarf mutant mapping BR GA