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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 {2., Hangzhou 310036, {2. 2. Department of Applied Mathematics, school of mathematical sciences, south {2. {2. 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.

Imaging theory of nonlinear second harmonic and third harmonic generations in confocal microscopy

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Science china(Physics,Mechanics & Astronomy) 2004年第1期47卷 8-16页

作者： TANG Zhilie1, XING Da2.& liu Songhao2.1. Department of Physics, south china normal university,{2., {2. 2. school for Information and Optoelectronic Science and Engineering, south china normal university,{2., {2. Correspondence should be addressed to Tang Zhilie (email: tangzhl@***) Received April 2., 2.03 1. Department of Physics South China Normal University 510631 Guangzhou China 2. school for Information and Optoelectronic Science and Engineering South China Normal University 510631 Guangzhou China

The imaging theory of nonlinear second harmonic generation (SHG) and third harmonic generation (THG) in confocal microscopy is presented in this paper. The nonlinear effect of SHG and THG on the imaging properties of confocal microscopy has been analyzed in detail by the imaging theory. It is proved that the imaging process of SHG and THG in confocal microscopy, which is different from conventional coherent imaging or incoherent imaging, can be divided into two different processes of coherent imaging. The three-dimensional point spread functions (3D-PSF) of SHG and THG confocal microscopy are derived based on the nonlinear principles of SHG and THG. The imaging properties of SHG and THG confocal microscopy are discussed in detail according to its 3D-PSF. It is shown that the resolution of SHG and THG confocal microscopy is higher than that of single- and two-photon confocal microscopy.

关键词： second harmonic generation, third harmonic generation, confocal microscopy, three-dimensional point spread function.

The generalized Roper-Suffridge extension operator in Banach spaces (Ⅲ)

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Science china Mathematics 2009年第11期52卷 2432-2446页

作者： ZHU YuCan1 & liu mingsheng2.1 Department of Mathematics,Fuzhou {2.,Fuzhou 350002.{2. 2.Department of Mathematics,south {2. normal {2.,guangzhou 510631,{2. 1. Department of Mathematics Fuzhou University Fuzhou 350002 China 2. Department of Mathematics South China Normal University Guangzhou 510631 China

Suppose that X is a complex Banach space with the norm ||·|| and n is a positive integer with dim X ≥n≥ 2. In this paper,we consider the generalized Roper-Suffridge extension operator Φn,β2.γ2....,βn+1,γn+1(f)... 详细信息

关键词： Roper-Suffridge extension operator biholomorphic starlike mapping almost spirallike mapping of type β and order α spirallike mapping of type β and order α

Optical pulse compression using a nonlinear optical loop mirror constructed from dispersion decreasing fiber

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Science china(Technological sciences) 2004年第1期47卷 33-50页

作者： CAO Wenhua & liu Songhaoschool of Information, Wuyi {2., Jiangmen 52.02., {2. school for Information and Optoelectronic Science and Engineering, south china normal university, guangzhou 510631, {2. 1. school of Information Wuyi University 529020 Jiangmen China 2. school for Information and Optoelectronic Science and Engineering South China Normal University 510631 Guangzhou China

A novel scheme to compress optical pulses is proposed and demonstrated numerically, which is based on a nonlinear optical loop mirror constructed from dispersion decreasing fiber (DDF). We show that, in contrast to the conventional soliton-effect pulse compression in which compressed pulses are always accompanied by pedestals and frequency chirps owning to nonlinear effects, the proposed scheme can completely suppress pulse pedestals and frequency chirps. Unlike the adiabatic compression technique in which DDF length must increase exponentially with input pulsewidth, the proposed scheme does not require adiabatic condition and therefore can be used to compress long pulses by using reasonable fiber lengths. For input pulses with peak powers higher than a threshold value, the compressed pulses can propagate like fundamental solitons. Furthermore, the scheme is fairly insensitive to small variations in the loop length and is more robust to higher-order nonlinear effects and initial frequency chirps than the adiabatic compression technique.

关键词： dispersion decreasing fiber (DDF), optical pulse compression, optical solitons.

ESTIMATE ON THE BLOCH CONSTANT FOR CERTAIN HARMONIC MAPPINGS UNDER A DIFFERENTIAL OPERATOR

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Acta Mathematica Scientia 2024年第1期44卷 295-310页

作者：陈洁玲刘名生 school of mathematical {2. South China Normal UniversityGuangzhou510631China

In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded ***,using these results,we present better estimations for the Bloch constants of certain harmonic mappings L(f),where f is a K-quasiregular harmonic or open ***,we establish three versions of BlochLandau type theorem for biharmonic mappings of the form L(f).These results are sharp in some given cases and improve the related results of earlier authors.

关键词： Bloch-Landau type theorem Bloch constant linear complex operator harmonic mapping biharmonic mapping univalent

Cooperative Rate Splitting Transmit Design for Full-Duplex-Enabled Multiple Multicast Communication Systems

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工程与科学中的计算机建模(英文) 2024年第1期138卷 619-638页

作者： Siyi Duan mingsheng Wei Shidang Li Weiqiang Tan Bencheng Yu school of Physics and Electronic Engineering Jiangsu Normal UniversityXuzhou221116China school of Computer Science and Cyber Engineering Guangzhou UniversityGuangzhou510006China school of Information Engineering Xuzhou Vocational College of Industrial TechnologyXuzhou221140China

This paper examines the performance of Full-Duplex Cooperative Rate Splitting(FD-CRS)with Simultaneous Wireless Information and Power Transfer(SWIPT)support in Multiple Input Single Output(MISO)*** a Rate Splitting Multiple Access(RSMA)multicast system with two local users and one remote user,the common data stream contains the needs of all users,and all users can decode the common data ***,each user can receive some information that other users need,and local users with better channel conditions can use this information to further enhance the reception reliability and data rate of users with poor channel *** using Cell-Center-Users(CCUs)as a cooperative relay to assist the transmission of common data can improve the average system *** maximize the minimum achievable rate,we optimize the beamforming vector of Base Station(BS),the common streamsplitting vector,the cooperative distributed beamvector and the strong user transmission power under the power budget constraints of BS and relay devices and the service quality requirements constraints of *** the whole problem is not convex,we cannot solve it ***,we propose a low complexity algorithm based on Successive Convex Approximation(SCA)technology to find the optimal solution to the problemunder *** simulation results show that FD C-RSMA has better gain andmore powerful than FD C-NOMA,HD C-RSMA,RSMA and NOMA.

关键词： Full-duplex cooperative rate segmentation SWIPT RSMA power control

The Bases and Base Set of Primitive Symmetric Loop-Free Signed Digraphs

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Journal of mathematical Research with Applications 2012年第3期32卷 313-326页

作者： Shuyong YI,Lihua YOU,Yuhan WU school of mathematical Science,{2. china normal university,Guangdong 510631,P.R.china school of mathematical Science South China Normal University Guangdong 510631

In this paper,we study the bases and base sets of primitive symmetric loop-free (generalized)signed digraphs on n *** obtain sharp upper bounds of the bases,and show that the base sets of the classes of such digraphs ... 详细信息

关键词： primitive signed digraph symmetric non-powerful base.

The Stamping Formability of AZ31 Magnesium Alloy Sheet Improved by Equal-channel Angular Pressing

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Journal of Wuhan university of Technology(Materials Science) 2010年第2期25卷 234-237页

作者：刘英 Department of Material Science and Engineering Jinan University

Equal channel angular pressing （ECAP） processing and annealing were applied to the AZ31 magnesium alloy sheets to evaluate the potential improvement in the mechanical properties and formability. The ECAP experiment was conducted at 300 ℃ in a die having an included angle of 90o between two channels by the BCZ route with the sheets rotated by 90°about the normal axis of plate plane. The tensile tests and conical cup tests were conducted at various temperatures from 2. to 2.0 ℃. The experimental results indicated that improving the working temperatures could lead to the soft in the material and the enhancement of ductility. Comparatively, the ECAPed AZ31 alloy sheets showed the lower yield strength and smaller conical cup value （CCV） than the unECAPed counterpart in the room temperature. The difference in yield strength between them became small in the elevated temperature, but the ECAPed samples still had the smaller CCV value, implying the improved formability. The texture of the AZ31 alloy sheets could be modified by ECAP and the decrease in the yield strength and more uniform deformation realized in the material, so the formability of AZ31 alloy sheets was improved.

关键词： AZ31 magnesium alloy sheets equal-channel angular pressing mechanical properties conical cup value (CCV)

OSCILLATION OF THIRD ORDER DELAY DIFFERENTIAL EQUATIONS WITH IMPULSES

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Annals of Differential Equations 2007年第4期23卷 450-460页

作者： liu Xiuxiang Xu Zhiting school of mathematical {2. South China Normal University Guangzhou 510631

In this paper we study the oscillation and asymptotic behavior of third order delay differential equations with impulses. Some new sufficient conditions which guarantee that every solution is oscillatory or converges ... 详细信息

关键词： oscillation impulses third order delay differential equations