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Transitional function of DG to CA3 in the hippocampus

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Progress in Natural science:Materials International 2007年第12期17卷 1436-1444页

作者： Yan Chuankui1 and Liu Shenquan2.1. Department of Mathematics, hangzhou Normal University, hangzhou 310036, {2. 2. Department of Applied Mathematics, school of Mathematical sciences, South {2. University of Technology, Guangzhou 510640, {2.) Department of Mathematics Hangzhou Normal University Hangzhou 310036 China Department of Applied Mathematics School of Mathematical Sciences South China University of Technology Guangzhou 510640 China

Using single cell channel model, the transmission features of CA3-DG network in the hippocampus are investigated. The influence of the stimulation on discharge pattern of pyramidal neurons is analyzed, which shows that it starts with period spiking discharges, followed by period-doubling bifurcation to chaos, and period 3 discharge evolving into chaos, and ultimately a period of bursting discharges. By the synaptic model, the CA3-DG network model is constructed, which analyzes the summation of postsynaptic currents in the network, the influence of postsynaptic current on discharge rhythm as well as the mechanism of bursting discharges. The strong capacity of spatiotemporal encoding in the network indicates the features of CA3 network during the information transmission process in the hippocampus. The modeling result with time delay of the synaptic transmission is in accordance with the experimental phenomena of action potential in the hippocampus.

关键词： hippocampus CA3-DG period-doubling bifurcation chaos.

Networked Kalman filtering with combined constraints of bandwidth and random delay

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science china(Information sciences) 2012年第10期55卷 2343-2357页

作者： GE QuanBo 1,2.WEN ChengLin 1 & XU TingLiang 1 1 school of Automation,hangzhou {2. University,hangzhou 310018,china 2.State Key Laboratory of Industrial Control Technology,Zhejiang University,hangzhou 31002.,china 1. school of Automation Hangzhou Dianzi University Hangzhou 310018 China2. State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou 310027 China

Kalman filter is a powerful tool in target tracking and self-localization across wireless sensor networks with many *** paper considers the filters design for networked systems with combined constraints of bandwidth and random delay,and proposes a kind of universal networked Kalman estimator for given linear time invariant(LTI) or determinate parameters(DP) systems,which are also called linear and determinate parameters(LDP) systems ***,two modeling ways to treat bit quantization error vector are given and the corresponding LDP systems taken after bit quantization are ***,we introduce an equivalent weighted summation form of the conventional linear Kalman filter,which fully uses two essential characteristics,namely offline computation property from the LDP systems and linear weighted summation property from the linear minimum mean square error ***,by adopting the replacement and innovation compensation operations,a kind of integrated networked estimator,involving two estimation algorithms with different modeling ways to bit quantization error actually,is presented based on the weighted summation filter for random delay *** proposed universal networked estimation algorithms have some outstanding advantages such as extensive application,concise algorithm structure,high estimate accuracy,and good running *** examples are demonstrated to validate the proposed networked estimation algorithms.

关键词： Kalman filter LDP systems LMMSE limited bandwidth random delay

Clustering-based hyperspectral band selection using sparse nonnegative matrix factorization

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Journal of Zhejiang University-science C(Computers and Electronics) 2011年第7期12卷 542-549页

作者： Ji-ming LI 1,2.Yun-tao QIAN 1 (1 school of Computer science and Technology,Zhejiang University,{2. 31002.,china) (2.Zhejiang Police College,{2. 310053,china) school of Computer science and Technology Zhejiang University Zhejiang Police College

Hyperspectral imagery generally contains a very large amount of data due to hundreds of spectral *** selection is often applied firstly to reduce computational cost and facilitate subsequent tasks such as land-cover classification and higher level image *** this paper,we propose a new band selection algorithm using sparse nonnegative matrix factorization (sparse NMF).Though acting as a clustering method for band selection,sparse NMF need not consider the distance metric between different spectral bands,which is often the key step for most common clustering-based band selection *** imposing sparsity on the coefficient matrix,the bands' clustering assignments can be easily indicated through the largest entry in each column of the *** results showed that sparse NMF provides considerable insight into the clustering-based band selection problem and the selected bands are good for land-cover classification.

关键词： Hyperspectral Band selection Clustering Sparse nonnegative matrix factorization

N-way blending problem of circular quadrics

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science china(Information sciences) 2010年第8期53卷 1546-1554页

作者： FANG MeiE 1,3 , Wang GuoZhao 2.& MA WeiYin 3 1 school of Computer science, {2. dianzi University, {2. 310081, china 2.Department of Mathematics, Zhejiang University, {2. 310018, china 3 Department of MEEM, City University of Hong Kong, Hong Kong, china 1. school of Computer science Hangzhou Dianzi University Hangzhou 310081 China3. Department of MEEM City University of Hong Kong Hong Kong China2. Department of Mathematics Zhejiang University Hangzhou 310018 China

A method of blending circular quadrics with parametric patches is proposed in this paper. It needs n rational bi-cubic B′ezier patches and two S-patches to blend n (n > 2. quadrics. Bi-cubic rational B′ezier patches are used to G 1 -continuously blend each pair of adjacent base surfaces. These patches enclose two n-sided holes. And an S-patch is used to fill each hole, which keeps nearly G 1-continuity. Explicit formulas of control points for both B′ezier patches and S-patches are derived from their constraint conditions, which make modeling by blending quadrics very simple and convenient. In addition, the shapes of the blending surfaces can be intuitively adjusted by free parameters.

关键词： circular quadrics blending n-way S-patch

Linguistic granular model: design and realization

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Progress in Natural science:Materials International 2005年第8期15卷 749-756页

作者： YUE Shihong 1,2., LI Ping2.and SONG Zhihuan2.1. Institute of Industrial Process Control, Zhejiang University, hangzhou 31002., china 2. {2. of Electric Engineering and Atomization, Tianjin University, Tianjin 300072. china) Institute of Industrial Process Control Zhejiang University Hangzhou 310027 China. school of Electric Engineering and Atomization Tianjin University Tianjin 300072 China

A new linguistic granular model is proposed and the effect of its parameters on the output is analyzed. The design of the model consists of two stages: using conditional fuzzy clustering for information granular, and integrating all information granules to final output. The integrating tool is fuzzy integral based on fuzzy measure, and the generalization of fuzzy integral increases flexibility of the linguistic granular model greatly. A heuristic algorithm to determine the parameters in the fuzzy integral is used to realize the linguistic model. Two experiments verify the feasibility of the proposed model.

关键词： linguistic model granular fuzzy clustering fuzzy integral.

Group sparse representation for image categorization and semantic video retrieval

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science china(Information sciences) 2011年第10期54卷 2051-2063页

作者： LIU YaNan 1,2.,WU Fei 2.& ZHUANG YueTing 2.1 school of Information,Zhejiang University of Finance & Economics,hangzhou,310018,{2. 2.College of Computer science and Technology,Zhejiang University,hangzhou,310012.{2. 1. school of Information Zhejiang University of Finance & Economics Hangzhou 310018 China2. College of Computer Science and Technology Zhejiang University Hangzhou 310012 China

Multimedia content analysis and management are a promising and challenging *** this paper we develop a novel approach to image representation,which we call group sparse representation (GSR),for image classification and video *** basic idea is to represent a test image as a weighted combination of all the training *** particular,we introduce two sets of weight coefficients,one for each training image and the other for each ***,we formulate our concern as a group nonnegative garrote *** resulting representations are sparse,and they are appropriate for discriminant *** on Caltech101 and PASCAL VOC2.08 image dataset and TRECVID2.05 video corpus testify that our proposed approach is efficient and effective.

关键词： compressive sensing group sparse representation bag-of-SIFT-words nonnegative garrote l1-minimization apcluster

Joint spatial registration and multi-target tracking using an extended PM-CPHD filter

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science china(Information sciences) 2012年第3期55卷 501-511页

作者： LIAN Feng1 , HAN ChongZhao1, LIU WeiFeng2. LIU Jing1 & YUAN XiangHui1 1SKLMSE Lab, MOE KLINNS Lab, school of Electronics and Information Engineering, Xi’an Jiaotong University, Xi’an 710049, china 2.0} of Automation, hangzhou dianzi University, hangzhou 310018, china 1. SKLMSE Lab MOE KLINNS Lab School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an 710049 China2. School of Automation Hangzhou Dianzi University Hangzhou 310018 China

An extended product multi-sensor cardinalized probability hypothesis density (PM-CPHD) filter for spatial registration and multi-target tracking (MTT) is proposed. The number and states of targets and the biases of sensors are jointly estimated by this method without the data association. Monte Carlo (MC) simulation results show that the proposed method (i) outperforms, although computationally more expensive than, the extended multi-sensor PHD filter which has been proposed for joint spatial registration and MTT; (ii) outperforms the multi-sensor joint probabilistic data association (MSJPDA) filter which is also extended in this study for joint spatial registration and MTT when the clutter is relatively dense.

关键词： multi-sensor spatial registration multi-target tracking (MTT) cardinalized probability hypothesis density (PHD) filter random finite set (RFS)

An elastic-plastic analysis of short-leg shear wall structures during earthquakes

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Earthquake Engineering and Engineering Vibration 2012年第4期11卷 525-540页

作者： Ding Jianguo Zhu Ying school of sciences Nanjing University of Science and Technology Huaxin Consulting CO. Ltd

Short-leg shear wall structures are a new form of building structure that combine the merits of both frame and shear wall structures. Its architectural features, structure bearing and engineering cost are reasonable. To analyze the elastic-plastic response of a short-leg shear wall structure during an earthquake, this study modified the multiple-vertical-rod element model of the shear wall, considered the shear lag effect and proposed a multiple-vertical-rod element coupling beam model with a new local stiffness domain. Based on the principle of minimum potential energy and the variational principle, the stiffness matrixes of a short-leg shear wall and a coupling beam are derived in this study. Furthermore, the bending shear correlation for the analysis of different parameters to describe the structure, such as the beam height to span ratio, short-leg shear wall height to thickness ratio, and steel ratio are introduced. The results show that the height to span ratio directly affects the structural integrity; and the short-leg shear wall height to thickness ratio should be limited to a range of approximately 6.0 to 7.0. The design of short-leg shear walls should be in accordance with the ＂strong wall and weak beam＂ principle.

关键词： short-leg shear wall multiple-vertical-rod element model shear lag effect bending shear correlationcoefficient coupling beam stiffness matrix elastic-plastic analysis

Progress of Lyman-alpha-based beam emission spectroscopy(Ly BES)diagnostic on the HL-2. tokamak

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Plasma science and Technology 2024年第3期26卷 118-125页

作者：周艺轩余羿许敏柯锐聂林徐皓赵光义刘灏袁子豪肖晨雨李继全肖池阶 the HL-2. Team Southwestern Institute of Physics Chengdu 610041People's Republic of China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082People's Republic of China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China

An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2. *** 2.-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from R=1960 mm to R=2.2. mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)*** this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector *** reflectance of the collection mirrors is measured to be~82.at 12. nm,and the aberration geometrical radius of the collection optics is tested to be~150μm in the aimed *** linear dispersion of the LyBES monochromator is designed to be~0.09 nm mm^(-1).The bandwidth of the detector system with the 5×10^(7)V A^(-1)preamplifier gain is measured to be~2.0 kHz,and the peak-to-peak noise of the detector system is tested to be~16 *** finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall performance of the LyBES diagnostic is to be confirmed in the next HL-2. campaign.

关键词： density fluctuation Ly BES BES vacuum ultraviolet