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Journal of Wuhan university of technology(Materials Science) 2010年第3期25卷 432-436页

作者：欧忠文 Department of Architecture and Civil engineering Logistics Engineering University

In-situ characterization of non-aqueous nano-dispersion systems（NANDS） by freeze-etching transmission electron microscope（FETEM） was *** improve just-for-once successive rate of specimen preparation and get good characterization results,an improving specimen preparation method of freezing etching was ***,distribution and morphology of NANDS were directly *** information of particle dispersion feature and particle density can also be *** of the FETEM characterization is *** with laser scattering method,which is liable to give positive error especially for small size particle anchoring disperser,FETEM characterization can give more accurate measurement of particle ***,FETEM can give dispersion feature of nanoparticle in non-aqueous medium.

关键词： non-aqueous nano-dispersion system dispersion state in-situ characterization freeze-etching laser scattering method

Multi-channel neural mass modelling and analyzing

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Science China(information Sciences) 2011年第6期54卷 1283-1292页

作者： CUI Dong 1 , LI XiaoLi 2., JI XueQing 3 & LIU LanXiang 3 1 Institute of information Science and engineering, Yanshan{2., Qinhuangdao 066004, China 2.Institute of electrical engineering, Yanshan{2., Qinhuangdao 066004, China 3 The No.1 Hospital of Qinhuangdao, Qinhuangdao 066000, China 1. Institute of information Science and engineering Yanshan University Qinhuangdao 066004 China2. Institute of Electrical Engineering Yanshan University Qinhuangdao 066004 China3. The No.1 Hospital of Qinhuangdao Qinhuangdao 066000 China

Multi-channel neural signals generated by a computational model can help understand the mechanism of EEG rhythms, analyze brain functional connectivity and evaluate neural signal processing methods. In this study, a two-kinetics lumped-parameter neural mass model is extended to a multi-kinetics and multi-channel coupled model. This new model can effectively simulate the coupled dynamics activities between different areas in the brain. The simulation results show that the proposed model can generate neural signals with various frequency bands, from delta wave (1-4 Hz) to gamma wave (30-70 Hz), and the dynamics of the simulated neural signals is more complicated. The simulation analysis can also reveal the relationship between the coupled neural networks and the rhythm of neural populations, and the simulated neural signals can present the bi-modal and uni-modal phenomenon in the frequency domain when the coupling strength of models increases. Finally, analysis of an epileptic EEG signal from a rat demonstrates that the coupling among the neural populations can induce a large-scale seizure.

关键词： multi-channel neural mass model coupling spectrum synchronization epilepsy

Theory study of shapes in ^(187,189)Tl nuclei

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Science China(Physics,Mechanics & Astronomy) 2009年第6期52卷 818-821页

作者： LIU YanXin1, YU ShaoYing1,2.3, SHEN CaiWan1,5 & DONG YongSheng1,2.4 1 School of Science, Huzhou Teachers college, Huzhou 313000, China 2.School of Science and information{2., Zhejiang Normal university, Jinhua 32.000, China 3 Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080, China 4 Department of Physics, Jining Teachers college, Jining 012.00, China 5 Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of lanzhou, lanzhou 730000, China School of Science Huzhou Teachers College Huzhou 313000 China School of Science and information engineering Zhejiang Normal University Jinhua 321000 China Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China Department of Physics Jining Teachers College Jining 012000 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The nuclear shapes of 187,189Tl were investigated theoretically in this work. The total routhian surface (TRS) calculations were performed for N=106 and 108 isotopes of thallium (Z=81). The single-particle energies were obtained from the deformed Woods-Saxon potential, with the Lipkin-Nogami (LN) treatment of pairing. It is found that the collective oblate rotation coexists with the high-K prolate rotation. Superdeformed prolate rotation is included in this calculation.

关键词： nuclear shape oblate rotation prolate rotation

Multiparty simultaneous quantum identity authentication with secret sharing

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Science China(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2.WEN QiaoYan3 & ZHANG Xing4,5 1 college of Computer Science and technology,Beijing{2. of technology,Beijing 10002.,China 2.State Key Laboratory of information Security (Graduate{2. of the Chinese Academy of Sciences),Beijing 100049,China 3 School of Science,Beijing{2. of Posts and Telecommunications,Beijing 100876,China 4 Institute of Electronic technology,information engineering{2.,Zhengzhou 450004,China 5 Trusted Computing Laboratory,Beijing{2. of technology,Beijing 10002.,China college of Computer Science technology Beijing University of Technology Beijing 100022 China State Key Laboratory of information Security [Graduate university of the Chinese Academy of Sciences] Beijing 100049 China School of Science Beijing University of Posts Telecommunications Beijing 100876 China Institute of Electronic technology Information Engineering University Zhengzhou 450004 China Trusted Computing Laboratory Beijing University of Technology Beijing 100022 China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

RBF neural network and active circles based algorithm for contours extraction

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Progress in Natural Science:Materials International 2007年第6期17卷 681-686页

作者： Zhou Zhiheng, Zeng Delu and Xie Shengli(college of Electronic & information{2., South China university of technology, Guangzhou 510640, China) college of Electronic and information{2. South China University of Technology Guangzhou 510640 China

For the contours extraction from the images, active contour model and self-organizing map based approach are popular nowadays. But they are still confronted with the problems that the optimization of energy function will trap in local minimums and the contour evolutions greatly depend on the initial contour selection. Addressing to these problems, a contours extraction algorithm based on RBF neural network is proposed here. A series of circles with adaptive radius and center is firstly used to search image feature points that are scattered enough. After the feature points are clustered, a group of radial basis functions are constructed. Using the pixels’ intensities and gradients as the input vector, the final object contour can be obtained by the predicting ability of the neural network. The RBF neural network based algorithm is tested on three kinds of images, such as changing topology, complicated background, and blurring or noisy boundary. Simulation results show that the proposed algorithm performs contours extraction greatly.

关键词： contours extraction RBF neural network dynamic clustering.

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曲柄滑块机构中滑块输出位移的可靠性分析

上海交通大学学报 2010年第12期44卷 1716-1720,1726页

作者：同长虹黄建龙兰州理工大学机电工程学院兰州730070 兰州城市学院机械监测与故障诊断研究所兰州730070

建立了运动副磨损量的计算模型.通过机构的运动学和动力学分析计算运动副元素之间的接触力和相对运动速度,在运动副连续接触理论和各随机因素符合正态分布的假设下,建立了曲柄滑块机构滑块输出位移可靠度模型,利用编写的Matlab计算程序... 详细信息

建立了运动副磨损量的计算模型.通过机构的运动学和动力学分析计算运动副元素之间的接触力和相对运动速度,在运动副连续接触理论和各随机因素符合正态分布的假设下,建立了曲柄滑块机构滑块输出位移可靠度模型,利用编写的Matlab计算程序对所建立的模型进行了实例计算,得出了机构随着工作时间的延长运动副元素的磨损影响越突出的结论.所建的模型可以估算机构工作一定时间后的运动精度可靠度,也可以推算在给定要求下机构的工作寿命.

关键词：曲柄滑块机构运动副磨损原始误差位移可靠性

Vector bundle constraint for particle swarm optimization and its application to active contour modeling

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Progress in Natural Science:Materials International 2007年第10期17卷 1220-1225页

作者： Zeng Delu, Zhou Zhiheng and Xie Shengli(college of Electronic and information{2., South China university of technology, Guangzhou 510641, China) college of Electronic and information{2. South China University of Technology Guangzhou 510641 China

Active contour modeling (ACM) has been shown to be a powerful method in object boundary extraction. In this paper, a new ACM based on vector bundle constraint for particle swarm optimization (VBCPSO-ACM) is proposed. Different from the traditional particle swarm optimization (PSO), in the process of velocity update, a vector bundle is predefined for each particle and velocity update of the particle is restricted to its bundle. Applying this idea to ACM, control points on the contour are treated as particles in PSO and the evolution of the contour is driven by the particles. Meanwhile, global searching is shifted to local searching in ACM by decreasing the number of neighbors and inertia. In addition, the addition and deletion of particles on the active contour make this new model possible for representing the real boundaries more precisely. The proposed VBCPSO-ACM can avoid self-intersection during contour evolving and also extract inhomogeneous boundaries. The simulation results proved its great performance in performing contour extraction.

关键词： boundary extraction active contour modeling particle swarm optimization velocity update vector bundle.

Direct gray-scale extraction of topographic features for vein recognition

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Science China(information Sciences) 2010年第10期53卷 2062-2074页

作者： KANG WenXiong 1, LI HuaSong 2.& DENG FeiQi 1 1 college of Automation Science and engineering, South China{2. of technology, Guangzhou 510640, China 2.School of information engineering, Wuyi{2., Jiangmen 52.000, China 1. college of Automation Science and engineering South China University of Technology Guangzhou 510640 China2. School of Information Engineering Wuyi University Jiangmen 529000 China

Binarization processing is a key step in most vein pattern recognition, but may create flaws such as leakage of some feature information. In order to overcome this problem, a new approach is explored in this paper which can extract topographic features directly from gray-scale vein images without binarization processing. First, an extreme graph of directional fields (EGDF) is calculated according to neighborhood information of every pixel, and then the intravenous main ridge of the image can be separated step by step from EGDF with the defined constraint template sets. After that, the sub-ridge is extracted from end points of the main ridge in range constraint image with the tracing method of maximal neighboring point. According to contrast experiment the proposed method is better than the traditional processing (performing binarization first and then skeletonization), in that it can overcome the problem that some separate vein lines are extracted incorrectly, and it can avoid extracting two neighboring vein lines as one ridge. As such, the proposed method is an effective way to extract topographic features for vein recognition

关键词： vein recognition feature extraction directional fields

Soft magnetic properties of (Ni_(50)Fe_(50)) SiO_2.granular thin films for high frequency application

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Rare Metals 2006年第z1期25卷 650-654页

作者： YANG Xiaolin GE Shihui RUAN Chengli college of Physics and Electronic Science University of Electronic Science and Technology of China Chengdu 610054 China Key Laboratory for Magnetism and Magnetic Materials of Ministry of EducationLanzhou University Lanzhou 730000 China College of Physics and Electronic Science University of Electronic Science and Technology of China Chengdu 610054 China

A series of (Ni50Fe50)x(SiO2.(1-x) films with different volume fraction x was fabricated by magnetron co-sputtering technique. The microstructure, magnetic and electrical properties were investigated systematically by using X-ray diffraction, transmission electronic microscope, vibrating sample magnetometer and the traditional four point measurement method of resistivity. The results show that the samples consist of nano-scaled Ni50Fe50 metallic particles with fcc structure uniformly embedded in amorphous insulating SiO2.matrix, and the particle size decreases with the decrease of x. The rapid change of coercivity with x is observed, and a minimum value 160 A·m-1 of Hc was obtained for the sample of x=0.83 with film thickness of 180 nm, which can be contributed to the exchange coupling between nano-scaled Ni50Fe50 particles. At the frequency lower than 1 GHz, the real part μ′ of complex permeability keeps about 110 and the image part μ″ is less than 15. Besides, this film exhibits high resistivity ρ=2.3 μΩ·cm, high saturation magnetization 4πMs=1.2. T, high in-plane magnetic anisotropy field Hk=6.37 kA·m-1, and the ferromagnetic resonance (FMR) frequency is estimated to be 2.8 GHz. Therefore, this film can be used in high frequency devices operating over 2.GHz.

关键词： thin films nanostructure magnetic properties

A Sound Quality Objective Evaluation Method Based on Auditory Peripheral Simulation Model

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Journal of Bionic engineering 2010年第2期7卷 199-208页

作者： Yinhan Gao~1,Jun Xie~2.Jie Liang~1,Xin Chang~3,Baojun Wu~2.1.Experimental Centre of Testing Science,Jilin university,Changchun 13002.,P.R.China 2.college of Instrumentation &{2. engineering,Jilin university,Changchun 130061,P.R.China 3.Laboratory of Applications and Computations in Electromagnetics and Optics,Department of{2. engineering, university of Washington,WA 98195-2.00,USA [a] Experimental Centre of Testing Science Jilin University Changchun 130022 P. R. China [b] College of Instrumentation & Electrical Engineering Jilin University Changchun 130061 P. R. China [c] Laboratory of Applications Computations in Electromagnetics Optics Department of Electrical Engineering University of Washington WA 98195-2500 USA

Based on auditory peripheral simulation model, a new Sound Quality Objective Evaluation (SQOE) method is presented,which can be used to model and analyze the impacts of head, shoulder and other parts of human body on sound wave *** method employs the artificial head technique, in which the head related transfer function was taken into account tothe outer ear simulation ***, a bionic artificial head was designed as the outer ear model with considering the outersound field in view of theory and physical *** the auditory peripheral simulation model was built, which mimicsthe physiological functions of the human hearing, simulating the acoustic signal transfer process and conversion mechanismsfrom the free field to the peripheral auditory ***, performance comparison was made between the proposed SQOEmethod and ArtemiS software, and the verifications of subjective and objective related analysis were *** show thatthe proposed method was economical, simple, and with good evaluation quality.

关键词： sound quality objective evaluation auditory peripheral simulation model artificial head head related transfer function