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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 sciences,{3., China 2. Graduate School of chinese academy of sciences,{3., China 3. Department of Physics, Zhoukou Normal University, Zhoukou 466100, China 4. Research Imaging {5., University of Texas Health Science {5., San Antonio, Texas 78229, USA 5. national asic design and engineering center, institute of automation, chinese academy of sciences,{3., China 6. Department of Physics, Zhejiang University, Hangzhou 3.0027, China) 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 {3. {3. 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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GIS-based risk analysis of debris flow:an application in Sichuan, southwest China

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International Journal of Sediment Research 2008年第2期23卷 138-148页

作者： B.F.DI1,2,3.N.S.CHEN1,P.CUI1,Z.L.LI1,Y.P.HE4,and Y.C.GAO1 3.1 Ph.D.,Chengdu institute of Mountain Hazards and Environment,CAS,Chengdu 610041,China,Department of Architecture & Environment,Sichuan University,Chengdu 610065.China,Graduate University of chinese academy of sciences,{3. {3.,China,2 Prof.,Department of Architecture & Environment,Sichuan University,Chengdu 610065.China,3.Graduate University of chinese academy of sciences,{3. {3.,China 4 Department of Civil and Environmental engineering,San Diego State University,5.00 Campanile Dr.San Diego,CA 92121,USA Ph.D. Chengdu Institute of Mountain Hazards and Environment CAS Chengdu 610041 China Department of Architecture & Environment Sichuan University Chengdu 610065 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Prof. Department of Architecture & Environment Sichuan University Chengdu 610065 China Graduate University of chinese academy of sciences Beijing 100049 China Department of Civil and Environmental engineering San Diego State University 5500 Campanile Dr. San Diego CA 92121 USA

Debris flow is a serious geologic hazard in *** is estimated that nationally debris flows cause up to 2 billion RMB(25. million US$) in damages and 3.0-600 deaths and injuries *** mitigate debris flow hazards,it is necessary to map,model,and identify zones of debris flow hazards and vulnerability as to inform the local people about the potential risk with a geographic information *** research presents a regional scale case study modeling debris flow risk(hazard and vulnerability) in Sichuan Province,Southwestern *** this area,3.290 debris flows have been identified and the spatial-temporal distribution and activity characteristics of them have been *** on the available meteorological data,a Digital Elevation Model with the rate of 1:25.,000 and a regional geological map,the 24-hr rainfall threshold(y) for debris flow occurrence is closely related(significant at 99% confidence level) to the index(x) defined using a geology factor(rock hardness:a) and a topographical factor(channel gradient:d) where y = 21 + 10200 / x,in which x = 2.7 × ea + 1000 × *** discipline is constructive in developing the rainfall threshold for debris flow activity in remote mountainous areas that lack *** a given watershed,a four-level debris flow hazard map is developed by comparing the rainfall threshold to the {3. rainfall intensities with 5.-,20-,and 5.year average recurrence intervals,*** degree of debris flow vulnerability is determined by the watershed socio-economic conditions.A four-class debris flow risk map,at the final phase of the research,is generated by combining debris flow hazards and *** the debris flow risk assessment,the Sichuan Province is classified into the slight,moderate,severe and very severe regions,which accounts for 3.%,19%,20% and 25. of total area respectively.

关键词： Debris flow Geographic information system Hazard Vulnerability Risk Rainfall threshold

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基于场效应晶体管的太赫兹探测器中天线设计的一种有效方法（英文）

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红外与毫米波学报 2018年第4期37卷 389-392页

作者：张博文颜伟李兆峰白龙 Grzegorz Cywinski Ivan Yahniuk Krzesimir Szkudlarek Czeslaw Skierbiszewski Jacek Przybytek Dmytro B.But Dominique Coquillat Wojciech Knap 杨富华中国科学院半导体研究所半导体集成技术工程研究中心北京100083 中国科学院大学北京100049 中国科学院半导体研究所超晶格实验室北京100083 波兰科学院高压物理研究所波兰华沙PL01-142 先进材料与技术中心中央实验室波兰华沙PL02-822 蒙彼利埃大学与法国国家科学研究院查尔斯·库伦实验室法国蒙彼利埃UMR5221

在场效应晶体管太赫兹探测器中,合理的天线设计可以增强晶体管和太赫兹波之间的耦合效率,从而提高太赫兹探测器的响应度.提出一种基于晶体管栅极边缘沟道电场的仿真来设计平面天线的方法.这种方法尤其适用于太赫兹波段晶体管输入阻抗不... 详细信息

在场效应晶体管太赫兹探测器中,合理的天线设计可以增强晶体管和太赫兹波之间的耦合效率,从而提高太赫兹探测器的响应度.提出一种基于晶体管栅极边缘沟道电场的仿真来设计平面天线的方法.这种方法尤其适用于太赫兹波段晶体管输入阻抗不容易得到的情况.通过流片完成的基于氮化镓高电子迁移率晶体管的太赫兹探测器的响应度测试证实了这种方法的有效性.集成碟形天线和双偶极子天线的太赫兹探测器最大响应度分别在170.7 GHz(15.8.4 V/W)和124.3.GHz(1047.2 V/W)频点处测得,这个测试结果接近基于晶体管栅极边缘沟道电场的仿真结果.

关键词：太赫兹探测器平面天线沟道电场场效应晶体管

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