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A novel current vector decomposition controller design for six-phase permanent magnet synchronous motor

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Journal of Central South University 2016年第4期23卷 841-849页

作者：袁雷胡冰新魏克银林莹 institute of communications Engineering PLA University of Science and Technology University

The vector control algorithm based on vector space decomposition （VSD） transformation method has a more flexible control freedom, which can control the fundamental and harmonic subspace separately. To this end, a current vector decoupling control algorithm for six-phase permanent magnet synchronous motor （PMSM） is designed. Using the proposed synchronous rotating coordinate transformation matrix, the fundamental and harmonic components in d-q subspace are changed into direct current （DC） component, only using the traditional proportional integral （PI） controller can meet the non-static difference adjustment, and the controller parameter design method is given by employing intemal model principle. In addition, in order to remove the 5th and 7th harmonic components of stator current, the current PI controller parallel with resonant controller is employed in x-y subspace to realize the specific harmonic component compensation. Simulation results verify the effectiveness of current decoupling vector controller.

关键词： six-phase PMSM current vector decomposition internal control resonant control

Spatiotemporal Similaritons in (3+l)-Dimensional Inhomogeneous Nonlinear Medium with Cubic-Quintic Nonlinearity

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communications in Theoretical Physics 2011年第5期55卷 871-877页

作者：陈翼翔陆璇辉 Department of Physics Institute of OpticsZhejiang University School of Electronics Information Zhejiang University of Media and Communications

We obtain exact spatiotemporal similaritons to a （3＋ l）-dimensional inhomogeneous nonlinear Schrodinger equation, which describes the propagation of optical pulses in a cubic-quintic nonlinearity medium with distributed dispersion and gain. A one-to-one correspondence between such self-similar waves and solutions of the elliptic equation is found when a certain compatibility condition is satisfied. Based on exact solutions, we discuss evolutional behaviors of self-similar cnoidal waves and chirped similaritons in two kind of typicai soliton control systems. Moreover, the comparison between chirped similaritons and chirp-free solitons is given.

关键词： spatiotemporal similaritons (3+l)-dimensional cubic-quintic nonlinear SchrSdinger equation dynamical behaviors

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President's Message

China communications 2015年第1期12卷 I0002-I0003页

作者： ZHANG Xinsheng China institute of communications(CIC)

Happy New Year!With China continuing to drive the information and communications technology(ICT)into its next phase of growth,there has never been a more exciting time for me totake helm of China communications Magazine ***.,a company that is playing a pivotal role in enhancing the publication quality and worldwide influence of the China communications,the only English-language

关键词：中国通信学会通信技术总统出版质量 IEEE 研究人员通信覆盖研究论文

Color Correction for Multi-view Video Using Energy Minimization of View Networks

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International Journal of Automation and computing 2008年第3期5卷 234-245页

作者： Kenji Yamamoto Ryutaro Oi National institute of Information and communications Technology

Systems using numerous cameras are emerging in many fields due to their ease of production and reduced cost, and one of the fields where they are expected to be used more actively in the near future is in image-based rendering （IBR）. Color correction between views is necessary to use multi-view systems in IBR to make audiences feel comfortable when views are switched or when a free viewpoint video is displayed. Color correction usually involves two steps： the first is to adjust camera parameters such as gain, brightness, and aperture before capture, and the second is to modify captured videos through image processing. This paper deals with the latter, which does not need a color pattern board. The proposed method uses scale invariant feature transform （SIFT） to detect correspondences, treats RGB channels independently, calculates lookup tables with an energy-minimization approach, and corrects captured video with these tables. The experimental results reveal that this approach works well.

关键词： Multi-view color correction image-based rendering (IBR) view networks (VNs) scale invariant feature transform (SIFT) energy minimization.

Nonautonomous Vortices in (2+1)-Dimensional Graded-Index Waveguide

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communications in Theoretical Physics 2015年第5期63卷 605-612页

作者：来娴静蔡晓鸥张解放 School of Physical Science and Technology Soochow University Department of Basic Science Zhejiang Shuren University Zhejiang University of media and communications

With the help of self-similarity transformation, we construct and study the nonautonomous vortices with different topological charges inside a planar graded-index nonlinear waveguide, analytically, and numerically. Although these vortices are approximate, they can reflect the real properties of self-similar optical beam during a short-term propagation. Existence of these autonomous vortices require delicate balances between the system parameters such as diffraction, nonlinearity, gain, and external potential. We are concerned with some special but interesting situations, and discussing the changes of the height, width, energy, and central position of the vortices as the increase of propagation distance. Moreover, we are also interested in the azimuthal modulational instability of the system, and comparing our prediction for the modulational instability growth rates to numerical results.

关键词： graded-index waveguide vortex nonautonomous modulational instability

Dissipative Vortex Solitons in Defocusing media with Spatially Inhomogeneous Nonlinear Absorption

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communications in Theoretical Physics 2018年第2期69卷 159-165页

作者： Xian-Jing Lai Xiao-Ou Cai Jie-Fang Zhang College of Basic Science Zhejiang Shuren University Hangzhou 310015China Zhejiang University of media and communications Hangzhou 310018China

In this paper,by solving a complex nonlinear Schr6dinger equation,radially symmetric dissipative vortex solitons are obtained analytically and are tested *** find that spatially inhomogeneous nonlinear absorption gives rise to the stability of dissipative vortex solitons in self-defocusing nonlinear medium in the presence of constant linear *** simulation reveals the interaction effect among linear gain and nonlinear loss in the azimuthal modulation instabilities of these vortices *** from vortex in this media,another noticeable feature of current setup the uniform linear gain indeed affects the stability of is that the steep spatial modulation of the nonlinear absorption can suppress sidelobes effectively and support stable vortex solitons in situations with uniform linear *** appropriate conditions,the vortex solitons can propagate stably and feature no symmetry breaking,although the beams exhibit radical compression and amplification as they propagate.

关键词： vortex dissipative soltitons nonlinear loss

Surface diffusion of Si, Ge and C adatoms on Si (001) substrate studied by the molecular dynamics simulation

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Chinese Physics B 2009年第10期18卷 4591-4597页

作者：陈智辉俞重远芦鹏飞刘玉敏 Key Laboratory of Information Photonics and Optical communications Ministry of Education institute of Information Photonics and Optical communications Beijing University of Posts and Telecommunications

Depositions of Si, Ge and C atoms onto a preliminary Si （001） substrate at different temperatures are investigated by using the molecular dynamics method. The mechanism of atomic self-assembling occurring locally on the flat terraces between steps is suggested. Diffusion and arrangement patterns of adatoms at different temperatures are observed. At 900 K, the deposited atoms are more likely to form dimers in the perpendicular [110] direction due to the more favourable movement along the perpendicular [110] direction. C adatoms are more likely to break or reconstruct the dimers on the substrate surface and have larger diffusion distances than Ge and Si adatoms. Exchange between C adatoms and substrate atoms are obvious and the epitaxial thickness is small. Total potential energies of adatoms and substrate atoms involved in the simulation cell are computed. When a newly arrived adatom reaches the stable position, the potential energy of the system will decrease and the curves turns into a ladder-like shape. It is found that C adatoms can lead to more reduction of the system energy and the potential energy of the system will increase as temperature increases.

关键词： molecular dynamics simulations Tersoff potential surface diffusion potential energy

Predicting spikes with artificial neural network

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Science China(Information Sciences) 2018年第6期61卷 170-172页

作者： Lihong CAO Jiamin SHEN Lei WANG Ye WANG Neuroscience and Intelligent media institute Communication University of China

Dear editor,Spikes or action potentials are prominent features in most brain neurons,through which neural information can be efficiently processed and reliably transmitted,and eventually form the basis underlying how ... 详细信息

关键词： FS RS Predicting spikes with artificial neural network

Biological clock: the oscillator of gene expression

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Science China(Life Sciences) 2018年第1期61卷 128-130页

作者： Qiang Yu Shanghai institute of Materia media Chinese Academy of Sciences

The 2017 Nobel prize in physiology or medicine was awarded to the discoveries of genes and molecular mechanisms of the circadian rhythm,which is any biological process that oscillates with a period of about 24 *** scientists from the United States,Jeffrey ***,Michael Rosbash,and Michael ***,shared the *** work is of great theoretical value in understanding the nature of life and the interactions of life with its environments.

关键词： Biological clock