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Recent advances in the data analysis method of functional magnetic resonance imaging and its applications in neuroimaging

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Progress in Natural Science:Materials International 2006年第8期16卷 785-795页

作者： TIAN Jie, YANG Lei and HU Jin (Institute of Automation, chinese academy of sciences, beijing 100080, china Graduate School of chinese academy of sciences, beijing 10003., china) Institute of Automation Chinese Academy of Sciences Beijing 100080 China. Graduate School of chinese academy of sciences Beijing 100039 China

Functional magnetic resonance imaging (fMRI) has opened a new area to explore the human brain. The fMRI can reveal the deep insights of spatial and temporal changes underlying a broad range of brain function, such as motor, vision, memory and emotion, all of which are helpful in the clinical investigation. In this paper, we introduce some recent-developed algorithms for fMRI signal detection such as model-driven method (general linear model, deconvolution model, non-linear model, etc. ) and data-driven method (principle component analysis, independent component analysis, self-organization mapping, clustered constrained non-negative matrix factorization, etc. ). We also propose several important applications of neuroimaging and point out their shortcomings and future perspectives.

关键词： fMR1 data analysis neuroimaging.

Tree　ring　analysis　for　determination　of　pollution　history　of　Chengde　City，north　china

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Journal of Environmental sciences 1996年第1期8卷 77-85页

作者： Jiang Gaoming(Institute of Botany, chinese academy of sciences,beijing 100044,china ) Inst Botany Chinese Acad of Sci Beijing China China

Air pollution history of sulphur and heavy metals since 1800 in Chengde City , north china,was studied by analyzing the concentrations of sulphur and heavy metals in growth rings of Pinus tabulaeformis Carr. Sulphur concentrations in the tree rings of 1910-1920, 1970-1980,and 1980-1990 have increased 1-2 , 3-5 and 10 times respectively as those in the tree ring of 1810-1820 (P china was founded.

关键词： tree rings Pinus tabulaeformis sulphur and heavy metals pollution history Chengde

Flow Instability and Its Control in Compression Systems

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Journal of Thermal Science 2003年第1期12卷 1-9页

作者： Jingyi ChenInstitute of Engineering Thermophysics, chinese academy of sciences, beijing 100080, china Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China

This paper reviews the development in the research of flow instability and its control over the recent ten or more years. This development was largely stimulated by the novel idea of active control of the aerodynamic instability in compressors. Three topics are covered in the paper, which appeared as the major themes towards the goal of stability enhancement. The first topic is the pre-stall behavior of rotating stall, which plays a vital role in designing the control scheme and discovering the convenient route to find the causal factors of flow disturbances potentially leading to stall. The second topic is the mechanism of blade passage flow during stall and its inception, which is the basic knowledge needed to manipulate the blade design for the stability improvement and eventually to predict the unsteady performance of the compressor system. The third topic is the recent trend of the control strategy based on the learning of active vs. passive methods. To introduce to the discussion of these topics, a brief description of the history of the recent development is given at the beginning of the paper. In discussing each topic, future works are also highlighted to enhance the further development of this long-standing problem in turbomachinery research and application.

关键词： compressors rotating stall pre-stall active/passive control wavelet.

N DIMENSIONAL FINITE WAVELET FILTERS

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Journal of Computational Mathematics 2003年第5期21卷 595-602页

作者： Si-long Peng (NADEC, Institute of Automation, chinese academy of sciences, beijing 100080, china) NADEC Institute of Automation Chinese Academy of Sciences 北京 100080

In this paper, a large class of n dimensional orthogonal and biorthognal wavelet filters (lowpass and highpass) are presented in explicit expression. We also characterize orthogonal filters with linear phase in this c... 详细信息

关键词： n Dimension Linear phase Wavelet filters.

Formation of Ultrafine Metal Particles and Metal Oxide Precursor on Anodized Al by Electrolysis Deposition

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Journal of Materials Science & Technology 2000年第1期16卷 50-54页

作者： Lingchuan LI (Institute of Chemical Metallurgy, chinese academy of sciences, beijing 100080, china) Institute of Chemical Metallurgy Chinese Academy of Sciences Beijing 100080 China

Nickel was deposited by ac electrolysis deposition in the pores of the porous oxide film of Al produced by anodizing in phosphoric acid. Ultrafine rod-shaped Ni particles were formed in the pores. At the same time a film of Ni oxide precursor was developed on the surface of the porous oxide film. The Ni particles and the Ni oxide precursor were examined by SEM, TEM and X-ray diffraction. The thickness of the barrier layer of the porous oxide film was thin and it attributed to the formation of the metal particles, while the formation of the oxide precursor was associated with the surface pits which were developed in the pretreatment of Al.

关键词： Al Formation of Ultrafine Metal Particles and Metal Oxide Precursor on Anodized Al by Electrolysis Deposition

A mixed method for measuring low-frequency acoustic properties of macromolecular materials

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 729-739页

作者： LIU Hongwei1,YAO Lei1,3,ZHAO Hong1,3,ZHANG Jichuan2,3 & XUE Zhaohong2 1. National Key Laboratory of Acoustics,Institute of Acoustics,chinese academy of sciences,beijing 100080,china 2. Institute of Chemistry,chinese academy of sciences,beijing 100080,china 3. Graduate university of chinese academy of sciences,beijing 100049,china National Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China Graduate university of chinese academy of sciences Beijing China Institute of Chemistry Chinese Academy of Sciences Beijing China

A mixed method for measuring low-frequency acoustic properties of macro-molecular materials is presented. The dynamic mechanical parameters of materials are first measured by using Dynamic Mechanical Thermal Apparatus(DMTA) at low frequen-cies,usually less than 100 Hz; then based on the Principles of Time-Temperature Super-position (TTS),these parameters are extended to the frequency range that acousticians are concerned about,usually from hundreds to thousands of hertz; finally the extended dynamic mechanical parameters are transformed into acoustic parameters with the help of acoustic measurement and inverse analysis. To test the feasibility and accuracy,we measure a kind of rubber sample in DMTA and acquire the basic acoustic parameters of the sample by using this method. While applying the basic parameters to calculating characteristics of the sample in acoustic pipe,a reasonable agreement of sound absorp-tion coefficients is obtained between the calculations and measurements in the acoustic pipe.

关键词： low-frequency acoustic properties,dynamic mechanical properties,Principles of Time-Temperature Superposition,acoustic pipe,sound absorption coefficient.

Compositions of heavy minerals in Northeastern china sandlands and provenance analysis

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Science china Earth sciences 2007年第11期50卷 1715-1723页

作者： XIE Jing1,2 & DING ZhongLi1 1 Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 2 Graduate university of chinese academy of sciences, beijing 100049, china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Graduate university of chinese academy of sciences Beijing China

Sand samples deposited since the Last Glacial Maximum (LGM) from the Hulun Buir, Horqin and Otin-dag sandlands were measured for their assemblages of heavy minerals and chemical compositions of detrital garnets and tourmalines. Heavy mineral assemblages of these three sandlands consist mainly of garnet, ilmenite, epidote and minor amphibole and magnetite. Garnets consist mainly of high Mg type-A ones (58% on average), and minor type-B ones. Toumalines are mainly composed of Mg-rich and minor Fe-rich ones. Compared with those of central-southern Mongolia and central Tarim, these three sandlands are derived from the Phanerozoic rocks of the Central Asian Orogenic Belt and the Archean and Paleoprotorozoic basement rocks of the North china Craton. Our results provide direct evidence that the present-day sands may be reworked from LGM ones. Differences of heavy mineral composi-tions occur between the samples of the three sandlands and Taklimakan Desert, indicating that the material of the western arid regions contributes little to the eastern sandlands.

关键词： heavy minerals,provenance,Northeastern china,garnet,tourmaline

Convergence of the Vlasov-Poisson-Fokker-Planck system to the incompressible Euler equations

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Science china Mathematics 2006年第2期49卷 255-266页

作者： XIAO Ling, LI Fucai & WANG Shu academy of Mathematics and Systems Science, chinese academy of sciences, beijing 100080, china Department of Mathematics, Nanjing university, Nanjing 210093, china College of Applied sciences, beijing university of Technology, beijing 100022, china academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China Department of Mathematics Nanjing University Nanjing China College of Applied sciences Beijing University of Technology Beijing China

We establish the convergence of the Vlasov-Poisson-Fokker-Planck system to the incompressible Euler equations in this paper. The convergence is rigorously proved on the time interval where the smooth solution to the incompressible Euler equations exists. The proof relies on the compactness argument and the so-called relative-entropy method.

关键词： Vlasov-Poisson-Fokker-Planck system incompressible Euler equations relative-entropy method.

Improving the accuracy of image-based forest fire recognition and spatial positioning

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Science china(Technological sciences) 2010年第S1期53卷 184-190页

作者： JIANG LiLi 1,QI QingWen 1,ZHANG An 1,GUO ChaoHui 2 & CHENG Xi 1,3 1 Institute of Geographical sciences and Natural Resources Research,chinese academy of sciences,beijing 100101,china 2 china Center for Resources Satellite Data and Applications,beijing 100094,china 3Graduate university of chinese academy of sciences,beijing 100049,china Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China china Center for Resources Satellite Data and Applications Beijing China Graduate university of chinese academy of sciences Beijing China

Forest fires are frequent natural *** is necessary to explore advanced means to monitor,recognize and locate forest fires so as to establish a scientific system for the early detection,real-time positioning and quick fighting of forest *** paper mainly expounds methods and algorithms for improving accuracy and removing uncertainty in image-based forest fire recognition and spatial ***,we discuss a method of forest fire recognition in visible-light *** are four aspects to improve accuracy and remove uncertainty in fire recognition:(1)eliminating factors of interference such as road and sky with high brightness,red leaves,other colored objects and objects that are lit up at night,(2)excluding imaging for specific periods and azimuth angles for which interference phenomena repeatedly occur,(3)improving the thresholding method for determining the flame border in image processing by adjusting the threshold to the season,weather and region,and (4)integrating the visible-light image method with infrared image ***,we examine infrared-image-based methods and approaches of improving the accuracy of forest fire recognition by combining the spectrum threshold with an object feature value such as the normalized difference vegetation index and excluding factors of disturbance such as interference signals,extreme weather and high-temperature ***,a method of visible analysis to enhance the accuracy of forest fire positioning is examined and realized;the method includes decreasing the visual angle,selecting central points,selecting the largest spots,and judging the selection of fire spots according to the central *** studies are examined and the results are found to be satisfactory.

关键词： forest fire monitoring spatial positioning accuracy improvement