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An aperiodic phenomenon of the unscented Kalman filter in filtering noisy chaotic signals

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Progress in Natural Science:Materials International 2007年第10期17卷 1235-1240页

作者： Fan Hongjuan1. Feng Jiuchao1.2. Xie Shengli2.and Wang Shiyuan1.1. Faculty of Electronic and information Engineering ,{1.west University, Chongqing 40071., china 2. School of Electronic and information Engineering, {1. china University of Technology, guangzhou 51.641. china) Faculty of Electronic and information Engineering Southwest University Chongqing 400715 China School of Electronic and information Engineering South China University of Technology Guangzhou 510641 China

A non-periodic oscillatory behavior of the unscented Kalman filter (UKF) when used to filter noisy contaminated chaotic signals is reported. We show both theoretically and experimentally that the gain of the UKF may not converge or diverge but oscillate aperiodically. More precisely, when a nonlinear system is periodic, the Kalman gain and error covariance of the UKF converge to zero. However, when the system being considered is chaotic, the Kalman gain either converges to a fixed point with a magnitude larger than zero or oscillates aperiodically.

关键词： chaos unscented Kalman filter Lyapunov exponents aperiodicity.

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 Songhao{1.. Department of Physics, south china Normal University, guangzhou 51.631. china 2. School for information and Optoelectronic Science and Engineering, south china Normal University, guangzhou 51.631. china 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.

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 Shenquan{1.. Department of Mathematics, Hangzhou Normal University, Hangzhou 31.036, china 2. Department of Applied Mathematics, School of Mathematical Sciences, south china University of Technology, guangzhou 51.640, china) 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.

Discovery of Permian island-arc basalts in the Cenxi area and the tectonic significance──A piece of evidence for the paleo-Tethyan tectonic belt in western Guangdong and eastern Guangxi

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Chinese Science Bulletin 1998年第21期43卷 1838-1842页

作者： ZHANG Boyou 1. zhao {1. 1. SHI Manquan 1. YANG Shufeng 2.and CHEN Hanlin 2.1. guangzhou Institute of Geochemistry, Chinese Academy of Sciences, guangzhou 51.640, china 2. Department of Earth Sciences, Zhejiang University, Hangzhou 31.02., china guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Department of Earth Sciences Zhejiang University Hangzhou China

Cenxi Permian basalts are the late Palaeozoic island-arc type basalts first found in south {1.. REE and trace element characteristics and distribution patterns show that this volcanic formation, which has been isotopically dated at {2. MaB.P. by the 39Ar/ 40Ar method, is of an active continental marginal island arc type, and that the tectonic environment at that time was an island-arc marginal sea or minor ocean basin related with the paleo-Tethyan tectonic belt in western Guangdong-eastern Guangxi.

关键词： spilite-keratophyre pillow lava Permian continental margin paleo-Tethyan evolution.

Glacial atmospheric CO_(2. decline in association with decrease of marine sedimentary phosphorus

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Science china Earth Sciences 2006年第3期49卷 322-330页

作者： WENG Huanxin1. ZHANG Xingmao1. WU Nengyou2. WANG Ying1. CHEN Lihong1. ZHONG Hexian2.& QIN Yachao1.1. Institute of Environment & Biogeochemistry, Zhejiang University, Hangzhou 31.02., china 2. {1. Marine Geological Survey, CGS, MLR, {1. 51.760, china 1. Institute of Environment & Biogeochemistry Zhejiang University Hangzhou 310027 China 2. guangzhou Marine Geological Survey CGS MLR Guangzhou 510760 China

The environmental and biogeochemical information extracted from the sediments col- lected from the northern shelf of the {1. {2. Sea shows that terrigenous inputs of phosphorus into the sea remained relatively constant, and the variation of phosphorus contents at different depths was caused by climatic and environmental changes. The findings also suggest that the vertical varia- tion of phosphorus content was opposite to those of calcium carbonate and cadmium, and the func- tional correlation between CO2.and PO43? in seawater was given by calculating the chemical equilib- rium, indicating that the accumulation of marine sedimentary phosphorus may have something to do with the variation of atmospheric CO2. The decreased phosphorus accumulation as well as the cor- respondingly-increased calcium carbonate content might be one of key factors causing glacial at- mospheric CO2.decline.

关键词： sedimentary phosphorus, calcium carbonate, atmospheric CO2. northern shelf of the south china Sea, biogeochemistry.

Highly efficient transformation of intact yeast-like conidium cells of Tremella fuciformis by electroporation

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Science china(Life Sciences) 2008年第10期51卷 932-940页

作者： GUO LiQiong1.2. liu Yong1. {1. ShuXian1. liu ErXian1.& LIN JunFang1.2.1 College of Food Sciences, south china Agricultural University, guangzhou 51.640, china 2.Institute of Biomass Research, south china Agricultural University, guangzhou 51.640, china 1. College of Food Sciences South China Agricultural University Guangzhou 510640 China 2. Institute of Biomass Research South China Agricultural University Guangzhou 510640 China

Tremella fuciformis is one of higher basidiomycetes. Its basidiospore can reproduce yeast-like conidia, also called the blastospore by budding. The yeast-like conidia of T. fuciformis is monokaryotic and easy to culture by submerged fermentation similar to yeast. So it is a good recipient cell for exogenous gene expression. In this study, two expression vectors pGlg-gfp containing gpd-Gl promoter and gfp gene and pGlg-hph containing gpd-Gl promoter and hph gene were constructed. The lowest sensitive concentration of hygromycin for the blastospore was determined on three types of media. Our ex- periments showed that the lowest sensitive concentration of hygromycin for the blastospore was 5 μg/mL on MA medium. The intact blastospores were transformed with the expression vector pGlg-hph by electroporation. The putative transformants were obtained by the MA selective medium. Experi- mental results showed that the most effective parameters for the electroporation of intact blastospores were obtained by using STM buffer, 1.0×1.8 cells/mL of blastospores, 2.0 μL in transformation volume, 6 μg plasmid, 2.0 kV/cm of electric pulse voltage, stillness culturing on MB liquid medium for 48 h after electroporation. In these transformation conditions, the efficiency reached 2.7 colonies/μg DNA. Co-transformation of plasmid pGlg-gfp and pGlg-hph with ratio of 1.1.was performed by electroporation with the optimal parameters. The putative co-transformants were obtained by the MA selective medium. Eight randomly selected colonies from the vast putative co-transformants were analyzed by PCR de- tection and southern blotting. The experiments showed that the gfp was integrated into the genomes of three transformants. The co-transformation efficiency was 37.5%. Green fluorescence was observed under laser scanning confocal microscope in these gfp positive transformants. This indicates that the exogenous gfp can be expressed effectively in the yeast-like conidia of T. fuciformis.

关键词： Tremella fuciformis electroporation yeast-like conidia intact cells gene expression hph gene gfp gene

Stability of impulsive stochastic functional differential systems in terms of two measures via comparison approach

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Science china({1. Sciences) 2012年第6期55卷 1313-1322页

作者： YAO FengQi 1.2.& DENG FeiQi 1.1.Institute of System Engineering,south {1. University of Technology,guangzhou 51.640,{1. 2.School of Electrical Engineering and information,Anhui University of Technology,Maanshan 2.3032.{1. 1. Institute of System Engineering South China University of Technology Guangzhou 510640 China2. School of Electrical Engineering and Information Anhui University of Technology Maanshan 243032 China

Comparison principles for general impulsive stochastic functional differential systems are *** the comparison principles and the theory of differential inequalities,stability and instability,involving two measures,of impulsive stochastic functional differential systems are *** stability and instability criteria are obtained,and two examples are also given to illustrate our results.

关键词： stochastic systems impulsive functional differential systems comparison principle stability in terms of two measures instability

Linearly time-varying channel estimation and training power allocation for OFDM/MIMO systems using superimposed training

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Science china({1. Sciences) 2011年第7期54卷 1456-1470页

作者： ZHANG Han 1.DAI XianHua 2.& Pan DaRu 1.1.School of Physics and Telecommunication Engineering,south {1. Normal University,guangzhou 51.006,{1. 2.Department of information Science and Technology,SUN Yat-sen University,guangzhou 51.02.,{1. 1. School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China2. Department of Information Science and Technology SUN Yat-sen University Guangzhou 510026 China

We address the problem of estimating the linearly time-varying (LTV) channel of orthogonal frequency division multiplexing (OFDM)/multiple-input multiple-output (MIMO) systems using superimposed training (ST).The LTV channel is modeled by truncated discrete Fourier *** on this model,a two-step approach is adopted to estimate the LTV channel over multiple OFDM *** also present performance analysis of the channel estimation and derive a closed-form expression for the channel estimation *** is shown that the estimation variances,unlike that of the conventional ST-based schemes,approach to a fixed lower-bound as the training length increases,which is directly proportional to information-pilot power *** wireless communication systems with a limited transmission power,we optimize the ST power allocation by maximizing the lower bound of the average channel *** results show that the proposed approach outperforms the frequency-division multiplexed training schemes.

关键词： OFDM/MIMO systems linearly time-varying channel estimation superimposed training training power allocation

Geomorphologic evolution and environmental changes in the Shaluli Mountain region during the Quaternary

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Chinese Science Bulletin 2005年第1期50卷 52-57页

作者： ZHOU Shangzhe1.2. XU liubing1. CUI Jianxin1. ZHANG Xiaowei1.& {1. Jingdong1.1. National Laboratory of Western china’s Environmental Systems of Ministry of Education of china and Department of Geography, Lan- zhou University, Lanzhou 730000, china 2. Department of Geography, south china Normal University, Guang- zhou 51.631. china National Laboratory of Western china''s Environmental Systems of Ministry of Education of china and Department of Geography Lanzhou University Lanzhou 730000 China Department of Geography South China Normal University Guangzhou 510631 China

Geologic and geomorphologic evidence from the Shaluli Mountain indicates that the planation surface that formed in the Late Tertiary disintegrated during the Late Pliocene-Early Quaternary. At the same time, rift ba- sins appeared on some parts of the planation surface, and began to accumulate fluvial-lacustrine sediment. These are interpreted as being the response of this region to Phase-A of the Qingzang Tectonic Movement. After this, the Shaluli Mountain continued to rise in several pulses. Faulting and incision by some large tributaries of the Jinsha and Yalong Rivers resulted in several rift river valleys and the earliest terraces. Generally, the planation surface in this region had been uplifted to about 3500—3700 m a.s.l. no later than 550—600 ka BP, after the Kunlun-Huanghe Tectonic Move- ment, and coupled with global glacial climate, and resulted in the earliest glaciation recognized so far in the Hengduan Mountains. At the same time, loess was deposited in the Ganzi area of the northern Shaluli Mountain. During the last glacial period, the Shaluli Mountain approached its present altitude and developed several large ice caps, such as the Daocheng Ice Cap and Xinlong Ice Cap, as well as several huge valley glaciers. These paleoglaciers produced some of the most spectacular glacial topography on the Tibetan Pla- teau.

关键词：地形学环境变化 Shaluli山脉展平面西藏高原 ESR-年代测定