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fMRI time series analysis based on stationary wavelet and spectrum analysis

Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2.3 , ZHAO Xia~4, SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, chinese academy of {2., beijing 100049, china 2. graduate school of chinese academy of sciences, beijing 100049, china 3. Department of Physics, Zhoukou Normal University, Zhoukou 466100, china 4. Research Imaging Center, University of Texas Health Science Center, San Antonio, Texas 782.9, USA 5. National ASIC Design and Engineering Center, Institute of Automation, chinese academy of {2., beijing 100049, china 6. Department of Physics, Zhejiang University, Hangzhou 31002., china) Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China graduate school of {2. academy of sciences Beijing 100049 China Department of Physics Zhoukou Normal University Zhoukou 466100 China Research Imaging Center University of Texas Health Science Center San Antonio TX 78229 United States National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing 100049 China Department of Physics Zhejiang University Hangzhou 310027 China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

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Improvement of the SLP simulation in the coupled AGCM-ocean surface wave model

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chinese Science Bulletin 2005年第20期50卷 2397-2400页

作者： YU Weidong1, 2. 3, LI Zhaoxin4 & YUAN Yeli3 1. Institute of Oceanology, chinese academy of {2., Qingdao 2.6071, china 2. graduate school of chinese academy of sciences, beijing 100049, china 3. Laboratory of Marine Science and Numerical Modeling, First Institute of Oceanography, State Oceanic Administration, Qingdao 2.6061, china 4. LMD/CNRS, Univ. Paris 6, Paris, France Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China graduate school of {2. academy of sciences Beijing 100049 China Laboratory of Marine Science and Numerical Modeling First Institute of Oceanography State Oceanic Administration Qingdao 266061 China LMD/CNRS Univ. Paris 6 Paris France

The coupled atmosphere-ocean general circulation models (CGCM) are now becoming the indispensable tools for the climate study. However, most models still suffer from unrealistic simulations. One problem is the troublesome climate drift. It may come from some unresolved aspects. One possibility is the poor air-sea surface flux description now adopted in CGCM. The commonly used solution for this problem is the so-called flux correction[1].

关键词：大气海洋循环模式气象学 SLP模拟

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Discussion on the dispersion & agglomeration of aircraft industry

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Journal of Pharmaceutical Analysis 2009年第3期21卷 192-197,208页

作者： Bo Chu1,2.. Institute of Geographic sciences and Natural Resources Research,CAS,beijing 100101 2. {2. school of the chinese academy of sciences,beijing 100049,china. Institute of Geographic sciences and Natural Resources Research CAS Beijing 100101 graduate school of the {2. academy of sciences Beijing 100049 China

The aircraft industry is crucial to the economy and security of a nation. In this paper,the spatial characteristics and patterns of the aircraft industry are analyzed on different spatial scales. It is found that there is a ’Matthew effect’ in the global aircraft industry and the spatial evolution of the industry is consistent with the industrialization process of the whole country. It is also revealed that the spatial evolution of the country is driven by both the centripetal forces including capital,talents,technology and agglomeration economies and the centrifugal forces including the comparative advantage,cost & risk sharing,emerging markets,development policy for less-developed regions and the military imperative. These forces have both market-stabilizing and market-disrupting effects on the spatial evolution of the aircraft industry. The study suggests that lessons drawn from the experiences in the United States and France are expected to be conducive to the rise of china’s aircraft industry in the future.

关键词： aircraft industry dispersion agglomeration spatial evolution

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WIND observations of plasma waves inside the magnetic cloud boundary layers

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Science Bulletin 2005年第18期 85-90页

作者： WEI Fengsi1 , ZHONG Dingkun1,2. FENG Xueshang1, YANG Fang1,2.& LIU Rui 1 1. SIGMA Weather Group, Laboratory for Space Weather, Center for Space Science and Applied Research, chinese academy of {2., beijing 100080, china 2. graduate school, chinese academy of {2., beijing 100049, china

Based on the WIND observational data for the plasma waves from thermal noise receptor (TNR) working on the frequency 4―2.6 kHz and the solar wind and the magnetic fields, we analyze the plasma wave activities in the 60 magnetic cloud’s boundary layers (BLs) and find that there are often various plasma wave activities in the BLs, which are different from those in the adjacent solar wind (SW) and the magnetic clouds (MC). The basic characteris-tics are that: (1) the enhancement of the Langmuir wave near the electronic plasma frequency (fpe) is a dominant wave ac-tivity, which occupies 75% investigated samples; (2. the events enhanced both in the langmuir and ion acustic (f < fpe) waves are about 60% of investigated samples; (3) broadband, continuous enhancement events in the plasma wave activities were observed in the whole frequency band of TNR, and about 30% of the 60 samples, however, were not observed in the SW and the MC investigated events; (4) although the ratio of the temperatures between the electon and proton, Te/Tp≤1, the ion caustic wave enhancement activities are still often observed in the BLs, which makes it difficult to ex- plain them by the traditional plasma theory. New results reported in this paper further show that the magnetic cloud’s BL is an important dynamic structure, which could provide useful diagnosis for understanding the cloud’s BL physics and could expand a space developing space plasma wave theory.

关键词： solar wind magnetic cloud boundary layer plasma waves.

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Fuzzy Adaptive Kalman Filter Algorithm for RUAV's Integrated Navigation System

Fuzzy Adaptive Kalman Filter Algorithm for RUAV's Integrated...

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第2.届中国控制与决策会议

作者： Lei Dai 1,2., Chong Wu 1,2., Juntong Qi 1 , Janda Han 1 1. State Key Laboratory of Robotics, Shenyang Institute of Automation, chinese academy of {2., Shenyang 110016 china 2. graduate school of the chinese academy of {2., beijing 100049 china

The Kalman filter has characteristics of the noise-sensitive. This paper analyzes the adaptive Kalman filter algorithms which are based on Sage-Husae, neural network and fuzzy logic method. And an adaptive Kalman filter based on fuzzy logic is designed to estimate the attitude, heading and velocity of the RUAV. Combining the characteristics of RUAV platform and analyzing the real flight data, the fuzzy inference rules are designed to change the filtering parameters. With the actual flight data, the simulation verifies the validity of this algorithm. The experiments prove that this method can improve the navigation precision of RUAV.

关键词： Integrated Navigation Adaptive Kalman Filter Fuzzy Logic

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四川丘陵区经济发展的核心要素及其驱动能力

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山地学报 2008年第6期26卷 707-713页

作者：王明杰方一平中国科学院水利部成都山地灾害与环境研究所中国科学院研究生院

以四川68个丘陵县(市、区)为研究区域和对象,采用Pearson相关分析法,选择农业总产值、规模以上工业总产值、规模以上工业增加值、全社会固定资产投资等要素与GDP、地方财政收入、人均GDP、人均地方财政收入等经济发展水平重点指标进行... 详细信息

以四川68个丘陵县(市、区)为研究区域和对象,采用Pearson相关分析法,选择农业总产值、规模以上工业总产值、规模以上工业增加值、全社会固定资产投资等要素与GDP、地方财政收入、人均GDP、人均地方财政收入等经济发展水平重点指标进行相关性分析,定量分析得出了工业发展水平、社会固定资产投入水平对丘陵区经济发展具有明显的驱动作用,并就驱动能力进行了定量测度,并选择传统农业县、工业较发达县、旅游和第三产业较发达县作为典型案例进行具体分析,最后,提出了丘陵区发展的主要思路和建议。

关键词：丘陵区工业发展水平社会固定资产投入驱动能力

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黑水县芦花沟泥石流灾害治理现状与建议

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山地学报 2006年第2期24卷 181-185页

作者：张金山王士革孟国才张桂香中国科学院水利部成都山地灾害与环境研究所中国科学院水利部成都山地灾害与环境研究所四川成都610041 四川成都610041中国科学院研究生院北京100049

芦花沟是岷江水系黑水河中游右岸一级支流,历史上曾多次暴发泥石流,对黑水县城芦花镇造成了严重的危害和威胁。自上世纪80年代对其进行综合治理后,泥石流得到了有效控制。但由于工程年久失修,加之近几年降水量偏高,该沟泥石流有进一步... 详细信息

芦花沟是岷江水系黑水河中游右岸一级支流,历史上曾多次暴发泥石流,对黑水县城芦花镇造成了严重的危害和威胁。自上世纪80年代对其进行综合治理后,泥石流得到了有效控制。但由于工程年久失修,加之近几年降水量偏高,该沟泥石流有进一步活跃的趋势。仅2.04年就发生了3次泥石流,其中09-30泥石流冲出物近1×104m3,规模较大,并在排导槽中产生堵塞,幸得当地政府及时启动紧急预案进行了疏通,县城才得以平安。为了消除隐患,减轻灾害,我们对该沟泥石流进行了调查分析,提出了相应的应急措施和进一步防治对策。

关键词：芦花沟泥石流治理

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Infrared Galaxies in the Nearby Universe

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chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 643-652页

作者： Jian-Ling Wang 1 National Astronomical Observatories,chinese academy of {2.,beijing 100012.china 2.graduate school of chinese academy of {2.,beijing 100049,china National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China graduate school of {2. academy of sciences Beijing 100049 China

We used the Sloan Digital Sky Survey （SDSS） Data Release 5 （DR5） to study the morphological properties of 1137 nearby infrared （IR） galaxies, most of which are brighter than 15.9 mag in r-band. This sample was drawn from a cross-correlation of the Infra-Red Astronomical Satellite （IRAS） point source catalog redshift survey with DR5 at z ≤ 0.08. Based on this IR galaxy sample, we constructed five volume-limited sub-samples with IR luminosity ranging from 10^9.5 L⊙ to 10^12.⊙. By deriving the IR luminosity functions （LF） for different morphological types, we found that normal spiral galaxies are the dominant population below LIR ~ 8 ~ 10^10 L⊙; while the fraction of barred spiral galaxies increases with increasing IR luminosity and becomes dominant in spiral galaxies beyond LIR ≈ 5 × 10^10L⊙. As the IR luminosity decreases, the IR galaxies become more compact and have lower stellar masses. The analysis also shows that normal spiral galaxies give the dominant contribution to the total comoving IR energy density in the nearby universe, while, in contrast, the contribution from peculiar galaxies is only 39%.

关键词： galaxies evolution galaxies interactions galaxies starburst infrared galaxies galaxies luminosity function

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Geometry of Broad Line Regions of Active Galactic Nuclei

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chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 50-62页

作者： Xiao-Rong Lü1 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of {2., beijing 100049 2.graduate school of chinese academy of {2., beijing 100049 Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 graduate school of {2. academy of sciences Beijing 100049

It has long remained an open question as to the geometry of the broad line region （BLR） in active galactic nuclei （AGNs）. The reverberation mapping technique which measures the response of the broad emission lines to the ionizing continuum, when combined with multiwavelength continuum fitted by sophisticated accretion disks, provides a way of probing the BLR geometry. We analyze a sample of 35 AGNs, which have been monitored by the reverberation mapping campaign. In view of energy budget, the reverberation-based BH masses are found to be in agreement with those obtained by accretion disk models in two thirds of the present sample while the reverberation mapping methods underestimate the BH masses in about one third of objects, as also suggested by CoUin et al. in a recent work. We point out that there are obviously two kinds of BLR geometry, which are strongly dependent on the Eddington ratio, and separated by the value LBol/LEdd - 0.1. These results prefer a scenario of the disk and wind configuration of the BLR and identify the Eddington ratio as the physical driver regulating the wind in the BLR.

关键词： accretion, accretion disks - galaxies active - galaxies Seyfert - quasars general

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Valuations on arithmetic surfaces

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Science china Mathematics 2009年第1期52卷 66-76页

作者： XU Ning Department of Mathematics, graduate school of {2. academy of sciences, beijing 100049, china Department of Mathematics Graduate School of Chinese Academy of Sciences Beijing China

In this paper, we give the definition of the height of a valuation and the definition of the big field ? p,G , where p is a prime and G ? ? is an additive subgroup containing 1. We conclude that ? p,G is a field and ? p,G is algebraically closed. Based on this the author obtains the complete classification of valuations on arithmetic surfaces. Furthermore, for any m ? p,G n ∈ ?, let V m,n be an ∝-vector space of dimension n - m + 1, whose coordinates are indexed from m to n. We generalize the definition of ? p,G , where p is a prime and G ? V m,n is an additive subgroup containing 1. We also conclude that ? p,G is a field if m ? 0 ? n.

关键词： valuation height rank totally ordered group big field transcendental number 14J10

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