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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, {2. Academy of sciences, Beijing 100049,{3. 2. Graduate School of {2. Academy of sciences, Beijing 100049,{3. 3. Department of physics, Zhoukou Normal University, Zhoukou 466100,{3. 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, {2. Academy of sciences, Beijing 100049,{3. 6. Department of physics, Zhejiang University, Hangzhou 3.002.,{3.) Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Graduate School of chinese 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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Exotic structure of the third excited state in^(2.)Na

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chinese Science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2.3. LIANG Yujie1,2.3. DENG Fuguo1,2.3. LIU Zuhua1,4 & ZHOU Hongyu1,2.3.1. Key Laboratory of Beam Technology and Material Modification of Minister of Education, Beijing Normal University, Beijing 100875, china 2. institute of Low energy Nuclear {3., and Department of Material Science and Engineering, Beijing Normal University, Beijing 100875, china 3. Beijing Radiation Center, Beijing 100875, china 4. china institute of Atomic energy, Beijing 102.13. china Key Laboratory of Beam Technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China institute of Low energy Nuclear {2. Department of Material Science and Engineering Beijing Normal University Beijing 100875 China Beijing Radiation Center Beijing 100875 China china institute of Atomic {2. Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficie... 详细信息

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (2.1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73. and 2.1/2.5.2. fm respectively. The P value and the contribution of the asymptotic part to the 2.1/2.are compared with those of several other low energy states in 2.Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 2.Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 2.Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

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Inconsistency between WMAP data and released map

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chinese Science Bulletin 2010年第10期55卷 907-909页

作者： LIU Hao1 & LI TiPei1,2.3.1 Key Laboratory of Particle Astrophysics,{2. of high {3. physics,chinese Academy of sciences,Beijing 100049,china 2.Department of physics & Center for Astrophysics,Tsinghua University,Beijing 100084,china 3.Department of Engineering physics & Center for Astrophysics,Tsinghua University,Beijing 100084,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Department of physics & Center for Astrophysics Tsinghua University Beijing China Department of Engineering physics & Center for Astrophysics Tsinghua University Beijing China

A remarkable inconsistency between the calibrated differential time-ordered data (TOD) of the Wilkinson Microwave Anisotropy Probe (WMAP) mission,which is the input for map-making,and the cosmic microwave background (CMB) temperature maps published by the WMAP team is revealed,indicating that there must exist a serious problem in the map making routine of the WMAP *** inconsistency is easy to be confirmed without the use of WMAP map-making *** view of the importance of this issue for cosmology study,we invite readers to check it by themselves.

关键词：威尔金森微波各向异性探测器 WMAP 地图制作宇宙微波背景有序数据制作软件 TOD CMB

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Simulation study of real-time monitor for BEPC-Ⅱ luminosity

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Science china(Technological sciences) 2010年第5期53卷 1215-1219页

作者： SHAN Qing1,2.WU Jian2.XUE Zhen2.XU ZiZong2.HU Tao3.WANG YiFang3.& WANG XiaoLian2.1 College of Material Science and Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 2.0016,{2. 2.Department of Modern physics,University of Science and Technology of china,Hefei 2.0}02.,{2. 3.4},chinese Academy of sciences,Beijing 100049,{2. College of Material Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing China Department of Modern physics University of Science and Technology of China Hefei China institute of high {2. {3. Chinese Academy of Sciences Beijing China

A fast and real time luminosity monitor system will be used in the BEPC-Ⅱ(Beijing Electron Positron Collider,china).Photons generated in radiative Bhabha scattering at the interaction point are transformed into charged particles,and then the luminosity of each bunch pair is measured through collecting the Cherenkov light produced by charged particles in fused *** whole process happening in the detector is *** physics acceptance and detection threshold with the monitor accu-racy of 1% are set based on the simulation spectra of photoelectron yield calibrated by e-beam data.

关键词： luminosity BEPC-Ⅱ Cherenkov detector radiative Bhabha

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Virtualities of quark and gluon in QCD vacuum

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Science china(physics,Mechanics & Astronomy) 2008年第10期51卷 1439-1447页

作者： ZHOU LiJuan1, QIN SongMei2. WU Qing3.& MA WeiXing4 1 Collaboration Group of Hadron physics and Non-perturbative QCD Study, Guangxi University of Tech- nology, Liuzhou 545006,{2. 2.Department of physics, Guangxi University, Nanning 540003.{2. 3.Department of physics, Qingdao University, Qingdao 2.6071,{2. 4 institute of high energy physics, chinese Academy of sciences, Beijing 100049,{2. Collaboration Group of Hadron physics and Non-perturbative QCD Study Guangxi University of Technology Liuzhou China Department of physics Guangxi University Nanning China Department of physics Qingdao University Qingdao China institute of high {2. {3. Chinese Academy of Sciences Beijing China

The non-local vacuum condensates of quantum chromodynamics (QCD) describe the distributions of quarks and gluons in the non-perturbative QCD vacuum state. Physically, this means that vacuum quarks and gluons have a nonzero mean-squared momentum in the vacuum, called virtuality. The quark virtuality is given by the ratio of the local quark-gluon mixed vacuum condensate to the quark local vacuum condensate. The gluon virtuality is expressed by gluon vacuum condensates and four-quark vacuum condensates. We study the two virtualities by solving Dyson-Schwinger Equations and calculating quark and gluon vacuum condensates. Our theoretical results for quark virtuality are in good agreement with many other theoretical model predictions such as QCD sum rules and lattice QCD calculations. Our calculation on gluon virtuality is initial and the results are quite interesting.

关键词： quark gluon virtuality QCD vacuum condensate non-perturbative QCD

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Heavy ion reactions around the Coulomb barrier

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中国科学：物理学、力学、天文学英文版 2011年第S1期54卷 6-13页

作者： ZHANG HuanQiao1, LIN ChengJian1, JIA HuiMing1, ZHANG ChunLei1,2. ZHANG GaoLong1,3. YANG Feng1, LIU ZuHua1, AN GuangPeng1, WU ZhenDong1, XU XinXing1 & JIA Fei1 1 china {2. of Atomic energy, P. O. Box 2.5(10), Beijing 102.13. china 2.Particle Astrophysics Center, institute of high energy physics, chinese Academy of sciences, Beijing 10003., china 3.School of physics and Nuclear energy Engineering, Beihang University, Beijing 100191, china china institute of Atomic {2. Beijing China Particle Astrophysics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing China School of physics and Nuclear energy Engineering Beihang University Beijing China

The angular distributions of fission fragments for the 3.S+184W reaction near Coulomb barrier energies are measured. The ex perimental fission excitation function is obtained. The measured fission cross sections are decomposed into fusion-fission, quasi-fission and fast fission contributions by the dinuclear system (DNS) model. The hindrance to completing fusion both at small and large collision energies is explained. The fusion excitation functions of 3.S+90,96Zr in an {2. range from above to below the Coulomb barrier are measured and analyzed within a semi-classical model. The obvious effect of positive Q-value multi-neutron transfers on the sub-barrier fusion enhancement is observed in the 3.S+96Zr system. In addition, the excitation functions of quasi-elastic scattering at a backward angle have been measured with high precision for the systems of 16O+2.8Pb, 196Pt, 184W, and 154,152.m at energies well below the Coulomb barrier. Considering the deformed coupling effects, the extracted diffuseness parameters are close to the values extracted from the systematic analysis of elastic and inelastic scattering data. The elastic scattering angular distribution of 17F+12. at 60 MeV is measured and calculated by using the continuum-discretized coupled-channels (CDCC) approach. It is found that the diffuseness parameter of the real part of core-target potential has to be increased by 2.% to reproduce the experimental result, which corresponds to an increment of potential depth at the surface re gion. The breakup cross section and the coupling between breakup and elastic scattering are small.

关键词： fusion-fission quasi-fission fusion hindrance fusion enhancement surface diffuseness parameter exotic nuclei

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Properties of the 3.2.-[52.] band in the odd-N rare-earth nuclei

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 37-43页

作者： CHEN Liang1,2. ZHOU XiaoHong1,2. ZHANG YuHu1, ZHANG ShuangQuan3.& ZHU LiHua4 1institute of Modern {2., chinese Academy of {3., Lanzhou 73.000, china 2.raduate University of chinese Academy of {3., Beijing 100049, china 3.tate Key Laboratory of Nuclear {2. and Technology, School of {2., Peking University, Beijing 100871, china 4china institute of Atomic {13., Beijing 102.13. china institute of Modern physics Chinese Academy of Sciences Lanzhou China Graduate University of chinese Academy of sciences Beijing China State Key Laboratory of Nuclear physics and Technology School of Physics Peking University Beijing China china institute of Atomic {2. Beijing China

high-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2.[642., {2.2.[52.], and 11/2.[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2.branch of the ground state {2.2.[52.] band has been revised significantly. It is found that signature inversion occurs in the {2.2.[52.] band after the band crossing in 161Er. The systematics of the signature inversion associated with the {2.2.[52.] configuration in the rare-earth region is discussed. The band properties are analyzed within the framework of a triaxial particle-rotor model, and a triaxial deformation is proposed to the {2.2.[52.] band.

关键词： high-spin states signature inversion triaxial particle-rotor model

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The establishment of crystal position look-up table for positron emission tomography with block detectors

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Science china(Technological sciences) 2009年第8期52卷 2418-2423页

作者： CHAI Pei1,2.& SHAN BaoCi1 1 Key Laboratory of Nuclear Analytical Techniques, institute of high energy physics, chinese Academy of {2., Beijing 100049,{3. 2.Graduate University of chinese Academy of {2., Beijing 100049,{3. Key Laboratory of Nuclear Analytical Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate University of chinese Academy of sciences Beijing China

A method has been developed to establish the crystal position look-up table for positron emission tomography with block detectors. It is based on the principle that the counts in crystal position histogram obey the Gaussian mixture model (GMM). This method has taken full consideration of the characteristics of the GMM and the detector itself. The experimental results have proved that it is simple, reliable, and universal.

关键词： positron emission tomography position look-up table 2.D position histogram

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Potential land for plantation of Jatropha curcas as feedstocks for biodiesel in china

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Science china Earth sciences 2010年第1期53卷 120-127页

作者： WU WeiGuang 1,2.3.HUANG JiKun 1,3.& DENG XiangZheng 1,3.1 institute of Geographic sciences and Natural Resources Research,chinese Academy of sciences,Beijing 100101,china 2.Department of Economics and Management,Zhejiang Forestry University,Linan 3.13.0,china 3.Center for chinese Agricultural Policy,chinese Academy of sciences,Beijing 100101,china institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Department of Economics and Management Zhejiang Forestry University Linan China Center for chinese Agricultural Policy Chinese Academy of Sciences Beijing China

As a renewable energy,biofuel has attracted great attention in china and the rest of *** with the national food security,{2. recently has shifted its biofuel development priority from grain-based to non-grain-based biofuels,including forest-based biodiesel,since *** curcas is one of major biodiesel ***,there is rising debate on availability of land for expanding Jatropha curcas *** overall goal of this paper is to evaluate potential land for Jatropha curcas used as feedstock for biodiesel in *** on remote sensing data on land use,data on meteorological,soil and land slope,and suitable environment for Jatropha curcas plantation,this study uses Agro Ecological Zone method and considers social-economic constraints to evaluate potential suitable land for Jatropha curcas plantation in china's major Jatropha curcas production region,Southwest *** results show that while there are some potential lands to expand Jatropha curcas areas,amount of these lands will hardly meet the government's target for Jatropha curcas-based biodiesels development in the *** may need to reconsider its long-term targets on the development of Jatropha curcas-based biodiesels.

关键词： biodiesel Jatropha curcas potential land suitability evaluation Southwest china

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Superconductivity of small metal grains

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2.& ZHU Shunquan1,3.1. Department of physics, Shanghai Normal University, Shanghai 2.02.0}, china 2. Department of physics, Southwest Normal University, Chongqing 400715, china 3. Department of Computer and Electric Technology, Shanghai Business School, Shanghai 2.1400, china Department of physics Shanghai Normal University Shanghai China Department of physics Southwest Normal University Chongqing China Department of Computer and Electric Technology Shanghai Business School Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

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