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A single observer location method under the scatter signals position disturbance situation:the constraint total least square method

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Science China(information Sciences) 2011年第1期54卷 146-152页

作者： YANG TianChi1,YU ChaoQun2,WANG TianPeng1 & JIN Liang1 1National Digital Switching System engineering and Technological Research Center, Zhengzhou 450002,China 2Surveying and Mapping college of information engineering University, Zhengzhou 450002,China 1. National Digital Switching System engineering and Technological Research Center Zhengzhou 450002 China2. Surveying and Mapping College of Information Engineering University Zhengzhou 450002 China

A target position can be estimated using position information from scattered signals in the nonline-of-sight propagation environment in a single observer location *** is always an error in the final estimated result of the position obtained using scatter signals because measurement noise is *** reduce the total error of the system,we propose a method of converting the problem of optimizing location into a one of solving the extremes of the *** the problem of how to solve the extremes of the constraints is converted into an unconstrained problem by using the constrained total least squares(CTLS) ***,the Newton iteration method is used to obtain the optimized *** results also verify the capability of this method.

关键词： scatter position disturbing VOCTLS single observer location Newton iteration

On 3-colorability of planar graphs without adjacent short cycles

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Science China Mathematics 2010年第4期53卷 1129-1132页

作者： WANG YingQian 1,MAO XiangHua 1,LU HuaJing 2 & WANG WeiFan 1 1 college of Mathematics,Physics and information engineering,Zhejiang Normal University,Jinhua 321004,China 2 college of Basic Science,Ningbo Dahongying University,Ningbo 315175,China 1. college of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua 321004 China2. College of Basic Science Ningbo Dahongying University Ningbo 315175 China

A short cycle means a cycle of length at most *** this paper,we prove that planar graphs without adjacent short cycles are *** improves a result of Borodin et al.(2005).

关键词： planar graph coloring extension cycle

Synthesis of nanostructural ZnO using hydrothermal method for dye-sensitized solar cells

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Science China(Technological Sciences) 2010年第4期53卷 1146-1149页

作者： WANG ChunXiao1,2,ZHANG XiaoDan1,WANG DongFeng1,YANG ZhenHua1,2,JI WeiWei1,ZHANG CunShan2 & ZHAO Ying1 1 Institute of Photo-electronic Thin Film Devices and Technology of Nankai University,Key Laboratory of Photo-electronic information Science and Technology(Nankai University),Ministry of Education,Tianjin 300071,China 2 college of information engineering,Hebei University of Technology,Tianjin 300130,China 1. Key Laboratory of Photo-electronic information Science and Technology (Nankai University) Ministry of Education Institute of Photo-electronic Thin Film Devices and Technology of Nankai University Tianjin 300071 China2. College of Information Engineering Hebei University of Technology Tianjin 300130 China

ZnO nanocrystals with different morphologies were successful synthesized by a simple hydrothermal method combined with and without hexadecyl trimethyl ammonium bromide(CTAB).The phases and morphologies of the products were measured using X-ray diffraction(XRD),scanning electron microscopy(SEM),and transmission electron microscopy(TEM),*** results indicated that the ZnO nanocrystals with different morphologies were of hexagonal wurtzite *** nanorods were obtained without using CTAB,and then the morphology of ZnO changed to ZnO nanoflower and the density of nanoflower became denser with the increase of CTAB *** nanoflower and ZnO nanorod as photoanode were applied to dye-sensitized solar cells(DSSC),*** nanoflower shows a higher dye loading,so DSSC with the use of the ZnO nanoflower possesses a higher conversion efficiency than ZnO nanorod.

关键词： DSSC ZnO

Phase-matching analysis of four-wave mixing induced by modulation instability in a single-mode fiber

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Chinese Physics B 2012年第9期21卷 332-337页

作者：陈伟孟洲周会娟 Department of Optic information Science and Technology College of Optoelectronic Science and EngineeringNational University of Defense Technology

Four-wave mixing induced by modulation instability in a single-mode fiber is analyzed from the phase-matching point of view. For the two-channel transmission, a method is proposed to select the four-wave-mixing-induced sidebands, which is based on the proper use of a continuous-wave and a pulse as light sources. We find that a mass of sidebands are generated in the modulation instability resonance region, and the power of the sideband increases with not only the peak power of the pump pulse but also the continuous-wave power which acts as a seed. The research will provide guidance for fiber communication and sensing systems using wavelength division multiplexing technology.

关键词： four-wave mixing modulation instability phase matching

Research on Control System of Three-Level Inverter Based on Indirect Field Orientation

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Research on Control System of Three-Level Inverter Based on ...

A water-fat separation imaging method for the brain on low field magnetic resonance imaging

第24届中国控制与决策会议

作者： Jianhui Wang ,the college of information Science and engineering, Northeastern University Fenglong Shen,the college of information Science and engineering, Northeastern University college of Mechatronic engineering , Eastern Liaoning University and Yongkui Man the college of information Science and engineering, Northeastern University

In this paper, the mathematical model of induction motor based on rotor indirect field orientation in synchronous frame is introduced. Based on this, the current controller and the speed controller are designed in the indirect field-oriented space vector control system. The parameter is adjusted using the engineering design method and the three-phase asynchronous motor is controlled using SVPWM control strategy. The control system is simulated by MATLAB. The simulation results show that the proposed scheme is feasible and the space vector control system has a good dynamic respond.

关键词： Indirect flux-oriented decoupling SVPWM double closed-loop control system

来源： cnki会议评论

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Journal of Pharmaceutical Analysis 2009年第4期21卷 272-276页

作者： Hong-jun Tian1,Si-ping Chen2,Tian-fu Wang2,Xian-fen Diao2,Chong-xun Zheng1 1.Key Laboratory of Biomedical information engineering of Education Ministry,Xi’an Jiaotong University,Xi’an 710049 2.college of information engineering,Shenzhen University,Shenzhen 518060,China Key Laboratory of Biomedical information engineering of Education Ministry Xi'an Jiaotong University Xi'an 710049 China college of information engineering Shenzhen University Shenzhen 518060 China

Water-fat separation is a particularly important problem for magnetic resonance *** many methods have been proposed,the reliability is still *** this work,we have presented a method based on the combination of the branch-cut method and multigrid algorithm to get a more robust performance of water-fat ***,the branch-cut method is applied to identify residues,which violates the requirement that the interacting phase gradient around a closed path be *** and branches are marked to be zeros and filled to the weighting factor ***,the unwrapped phase array can be given by the multigrid ***,the Dixon method for water-fat separation is applied to the unwrapped phase *** for brain scanning on the 0.3T low field MRI system demonstrate the successful application of the proposed method.

关键词： water-fat separation Dixon weighted multigrid unwrapping

An algorithm to solve autocorrelation matrix singular value based on SNR estimation

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Optoelectronics Letters 2009年第1期5卷 41-44页

作者：赵继军张曙光赵文玉 college of information & Electronic engineering Hebei University of Engineering The Insititute of Telecommunication Transmission Ministry of Information Industry of China

SNR estimation of communication signals is important to improve demodulation performance and channel quality of communication system,thus it is an important research issue of communication *** to the core problem of autocorrelation matrix singular value in SNR estimation process,through making use of householder transforming autocorrelation matrix into tridiagonal matrix,and by using the relation of corresponding characteristic equation coefficients and singular value,a numerical algorithm is gi...

关键词： Acoustic intensity Algorithms Channel estimation Communication systems Correlation detectors Estimation Matrix algebra

Further study of sources of the imported cobalt-blue pigment used on Jingdezhen porcelain from late 13 to early 15 centuries

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Science China(Technological Sciences) 2008年第3期51卷 249-259页

作者： DU Feng1 & SU BaoRu2 1 Institute of Chemistry & Molecular engineering, Qingdao University of Science & Technology, Qingdao 266000, China 2 college of information Science Technology, Qingdao University of Science & Technology, Qingdao 266000, China Institute of Chemistry & Molecular engineering Qingdao University of Science & Technology Qingdao 266000 China college of information Science Technology Qingdao University of Science & Technology Qingdao 266000 China

Based on the conclusion of modern scientific analysis: the cobalt-blue pigment applied on Jingdezhen official porcelain during Yuan Dynasty and prior to Xuande reign of Ming Dynasty (1271―1425) contains high iron and low manganese con- tents, and the cobalt during Xuande and after Xuande periods (after 1426) of Ming Dynasty contains high manganese and low iron contents, in combination with the traditional archaeological method, the related historical textual records were in- vestigated and analyzed, the imported cobalt employed on Jingdezhen official porcelain was studied comprehensively, systematically and logically. In fact, 'Su Ma Li Qing' (Samarra-blue) and 'Su Bo Ni Qing' (Sumatra-blue) are definitely different cobalt ores originated in different places, because of their very similar translitera- tions in Chinese, the confusion has appeared in ancient books for more than 400 years, which considered 'Su Ma Li Qing' and 'Su Bo Ni Qing' as the same co- balt-blue pigment. In this article the mistake was corrected, the possible producing places and the approximate eras of the two pigments imported to China and used at Jingdezhen were also suggested.

关键词： imported cobalt-blue pigments employed on official blue-and-white porcelain Yuan Dynasty early Ming Dy- nasty Mn/Fe content ratio Su Ma Li Qing (Samarra-blue) Su Bo Ni Qing (Sumatra-blue) scientific archae- ological research transliteration

THE ALGORITHMS AND APPLICATIONS FOR DETERMINING PERMEABILITY COEFFICIENTS BY PULSE SPECTRUM TECHNIQUE

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Journal of Hydrodynamics 2002年第2期14卷 112-115页

作者： Wang Ling-ling college of Water Conservancy and Hydropower engineering, Hohai University, Nanjing 210098, China college of Water Conservancy and Hydropower engineering Hohai University Nanjing 210098 China

The determination of inhomogeneous permeability coefficient was studied as a parameter-control inverse problem for parabolic-type equation in this paper. By virtue of PST, the solution of the inverse problem is converted into an iteration procedure of solving a direct problem and solving a Fredholm integral equation of the first kind. Besides, Tikhonov normalization method is introduced to treat the uncertainty caused by the integral equation. Thus an algorithm for determining inhomogeneous permeability coefficient has been formulated and implemented. Numerical results show: (1) The algorithm presented in the paper is suitable to strongly inhomogeneous seepagel; (2) The additional information needed for solution is merely the seepage velocity on partical boundary, so that drill works can be reduced remarkably; (3) The algorithm is applicable to determining inhomogeneous transmission coefficients in groundwater engineering or other engineering.

关键词： inverse problem Pulse Spectrum Technique (PST) permeability coefficient parameter identification