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Using the rPatlak plot and dynamic FDG-PET to generate parametric images of relative local cerebral metabolic rate of glucose

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Science Bulletin 2012年第Z2期 3811-3818页

作者： WU YiGen 1,2*,ZHOU Yun 3,BAO ShangLian 2*,HUANG SungCheng 4.ZHAO XiaoHu 5 & LI Jun 2 1 school of Physics and Optoelectronic Engineering,Nanjing university of information Science and Technology,Nanjing 21004.,China 2 beijing City Key Laboratory of Medical Physics and Engineering,Peking university,beijing 100871,China 3 The Russell H.Morgan Department of Radiology and Radiological Science,school of Medicine,Johns Hopkins university,Baltimore,MD 21287,USA 4.Department of Molecular and Medical Pharmacology,UCLA David Geffen school of Medicine,university of California in Los Angeles,Los Angeles,CA 90095,USA 5 Imaging Department of Tongji Hospital of Tongji university,Shanghai 200065,China

Local cerebral metabolic rate of glucose(LCMRGlc) is an important index for the description of neural *** 18 F-fluoro-2-deoxy-D-glucose(FDG) positron emission tomography(PET) has been used for quantitative imaging of LCMRGlc in humans,but is seldom used routinely because of the difficulty in obtaining the input function noninvasively.A reference tissue-based Patlak plot model(rPatlak) was proposed to generate parametric images of LCMRGlc in a quantitative dynamic FDG-PET study without requiring blood *** emission scans(4.0.5,4.2 and 10×5 min) were acquired simultaneously with an IV bolus injection of 155 MBq of *** blood samples were collected during the scans via a catheter placed in the radial *** data were also generated using the same scan *** last ten scan data sets were used in a graphical analysis using the Patlak *** ratio of LCMRGlc estimated from the original Patlak(oPatlak,using plasma input) was used as the gold standard,and the standardized uptake value ratio(SUVR) was also calculated for *** different tissues including white matter,gray matter,and whole brain were chosen as reference tissues for *** of the reference region used,the slopes in the linear regression between oPatlak and rPatlak were closer to unity than the regression slopes between oPatlak and *** intercepts for the former were also closer to 0 than those for the latter *** squared correlation coefficients were close to 1.0 for both *** showed that the results of rPatlak were in good agreement with those of oPatlak,however,SUVR exhibited more *** simulation study also showed that the relative variance and bias for rPatlak were less than those for *** images obtained with rPatlak were very similar to those obtained with oPatlak,while there were differences in the relative spatial distribution between the images of SUVR and *** study validates that the rPatl

关键词： quantification local cerebral metabolic rate of glucose FDG-PET rPatlak method SUVR noninvasive parametric imaging

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Two-Level Unequal Error Protection Scheme in Image Transmission System Using Multilevel Codes in Rayleigh Fading Channel

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The Journal of China Universities of Posts and Telecommunications 2004年第z1期11卷 55-61页

作者： LI Zuo-wei~1, YANG Yi-xian~1, YUAN Dong-feng~2, HU Zheng-ming~1 1.information Security Center,beijing university of Posts and Telecommunications, beijing 100876, P.R. China 2.{4. of information Science and Engineering, Shandong university, Jinan 250100, P.R. China information Security Center Beijing University of Posts and Telecommunications Beijing 100876 P.R. China school of information Science and Engineering Shandong University Jinan 250100 P.R. China

In this paper, we propose a novel Unequal Error Protection (UEP) scheme with two levels for image transmission using Multilevel Codes (MLC). By providing the best protection for the most important data, the final recovered image quality is remarkably improved both in visual effect and in Peak Signal to Noise power Ratio (PSNR) performance.

关键词： rayleigh fading channel image transmission inequal error protection multilevel coding

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A MATCHED FILTER BANK BASED DOA ESTIMATION FOR ASYNCHRONOUS MULTIPATH CDMA CHANNELS

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Journal of Electronics(China) 2005年第3期22卷 220-228页

作者： YangWei ChenJunshi TanZhenhui TakisMathiopoulos schoolofElectronicsandinformationEng. BeijingJiaotongUniversityBeijing100044China DeptofElectricalandComputerEng. Univ.ofBritishColumbiaVancouverBCV6T1Z4Canada

In this paper, a Direction Of Arrival (DOA) estimation algorithm is proposed for multiuser signals through uplink asynchronous multipath Code Division Multiple Access (CDMA) channels. The algorithm is based directly on the correlation matrices of matched filter bank outputs of desired user’s multipath signals and it does not require that the elements of base station antenna array outnumber the multipath signals, which is necessary for the conventional sub-space based direction-finding algorithm. Simulation results show that the proposed algorithm estimates the DOA of multipath signals effectively and acceptably. The proposed algorithm has the prominent advantages of low complexity, simpleness and practicality, which make it much more suitable for practical application.

关键词： Code Division Multiple Access(CDMA) Direction Of Arrival(DOA) estimation Asynchronous multipath channel

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红鼻鱼群体结构的数学建模与仿真可视化

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水产学报 2010年第12期34卷 1869-1876页

作者：柳玲飞周应祺钱卫国赵媛王明上海海洋大学海洋科学学院上海海洋大学大洋生物资源开发和利用上海市高校重点实验室上海海洋大学大洋渔业资源可持续开发省部共建教育部重点实验室上海海洋大学信息学院

探索通过数学模型和计算机仿真模拟的方法,分析推测影响鱼群群体空间分布的主要因子。初步研究结果表明,在视觉、游泳能力等诸因子中,鱼类的视觉能力,包括视距和视野对鱼群结构有重要影响,其中最大视觉能力范围是主要因素。该实验结果... 详细信息

探索通过数学模型和计算机仿真模拟的方法,分析推测影响鱼群群体空间分布的主要因子。初步研究结果表明,在视觉、游泳能力等诸因子中,鱼类的视觉能力,包括视距和视野对鱼群结构有重要影响,其中最大视觉能力范围是主要因素。该实验结果为实验观察提供了启示。可视化仿真结果与红鼻鱼群体录像资料的对比验证结果表明,采用IBMs理论建立数学模型,进行模拟研究的方法可行,仿真模拟的鱼群动态结果可以表现出与红鼻鱼群体实际运动相类似的分布状态。表明可视化仿真技术有助于对群体运动问题的探索和理解。

关键词：数字仿真群体鱼类行为个体行为模型(IBMs)

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AN EFFICIENT MOTION ESTIMATION ALGORITHM FOR H.264.AVC H.264.AVC

AN EFFICIENT MOTION ESTIMATION ALGORITHM FOR H.264/AVC H.264...

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中国通信学会第六届学术年会

作者： Guo Yanjie~1,Liu Ruifang~2 (1 school of information and Communication Engineering,beijing university of Posts and Telecommunications,beijing 100876,China 2 school of information and Communication Engineering,beijing university of Posts and Telecommunications,beijing 100876,China)

Motion estimation plays an important role in the video compression standard,such as H.263,MPEG-2/4.and *** search(FS) is the most common and simple motion estimation algorithm,but owing to the FS algorithm resulting in huge computational complexity,so many fast motion estimation algorithms have been proposed instead of *** the paper,we discuss UMHexagonS algorithm, then we propose a fast ME algorithm based on *** simulation results show that proposed algorithm maintains an unnoticeable quality loss in terms of PSNR on average compared to FS and UMHexagonS but reduces motion estimation time.

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塔河油田碳酸盐岩缝洞型储集体动态连通性分析

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新疆石油地质 2011年第5期32卷 469-472页

作者：易斌崔文彬鲁新便杨敏中国地质大学资源学院湖北武汉430074 中国石化西北油田分公司采油一厂新疆库尔勒841000 中国石化西北油田分公司采油三厂新疆库尔勒841000 中国地质大学能源学院北京100083 中国石化西北油田分公司勘探开发研究院乌鲁木齐830011

塔河油田奥陶系油藏是大型碳酸盐岩裂缝和岩溶缝洞型油藏。油藏的储渗空间主要为规模不同的溶洞、裂缝带、溶蚀孔隙和微裂缝。油藏开发实践证实,油藏呈现出多缝洞系统、多压力系统、多个渗流单元的特征。针对储集层复杂的特点,提出了利... 详细信息

塔河油田奥陶系油藏是大型碳酸盐岩裂缝和岩溶缝洞型油藏。油藏的储渗空间主要为规模不同的溶洞、裂缝带、溶蚀孔隙和微裂缝。油藏开发实践证实,油藏呈现出多缝洞系统、多压力系统、多个渗流单元的特征。针对储集层复杂的特点,提出了利用动态信息分析油藏缝系统与洞系统之间连通性的研究思路和方法(包括油藏压力趋势分析法、井间生产干扰分析法、流体性质差异分析法、井间干扰试井法和示踪剂法等),并结合塔河油田实际资料,进行了流动单元初步划分和分析。

关键词：塔里木盆地塔河油田碳酸盐岩缝洞型油藏动态分析井间连通性流动单元

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内蒙古多伦县土地利用动态遥感监测应用研究

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水土保持学报 2002年第4期16卷 137-140页

作者：程博田淑芳刘常红中国地质大学地球科学与资源学院北京100083 中石化石油勘探开发研究院北京100083

在内蒙古多伦县土地利用现状的两轮调查中,利用多时相卫星图象(TM)数据,根据多伦地区各类地物的波谱特征,采用了假彩色合成及比值假彩色合成等遥感图象处理方法,建立了土地利用动态监测解译标志。在地理信息系统技术的支持下,对多伦地... 详细信息

在内蒙古多伦县土地利用现状的两轮调查中,利用多时相卫星图象(TM)数据,根据多伦地区各类地物的波谱特征,采用了假彩色合成及比值假彩色合成等遥感图象处理方法,建立了土地利用动态监测解译标志。在地理信息系统技术的支持下,对多伦地区土地利用的空间分布和面积进行了详细解译和测算,制作成动态遥感监测图,为多伦县地方政府提供了真实可靠的各类土地利用现状数据,为土地合理利用及沙化治理提出了相应对策。

关键词：遥感监测应用多伦县土地利用动态监测

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一种汉字姓氏电话码输入方法及其应用

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计算机工程与应用 2003年第19期39卷 71-73页

作者：罗仁郭盛芳阳庆节姚泽清中国矿业大学基础科学学院北京100083 首都医科大学计算机系北京100054 中国人民大学信息学院北京100872 解放军理工大学理学院南京211101

文章提出了一种汉字姓氏电话码输入方法及其一些应用。

关键词：中文输入电话码输入汉字姓氏

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Impacts of climate change and grazing intensity on soil organic carbon in alpine meadow

Impacts of climate change and grazing intensity on soil orga...

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2011 International Conference on Business Management and Electronic information(BMEI 2011)

作者： Xiaojia Li 1 2 Xianzhou Zhang 1 Hongtao Jiang 3 Qinglong Ma 4.Zhenxi Shen 1 Yuzhi Fan 1 2 Wei Yan 1 2 1 Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences beijing China 2 Graduate university of Chinese Academy of Science beijing China 3 school of Geography beijing Normal university beijing China 4.NO.2 Middle school of Xilingol League Xilinhot Inner Mongolia China

In this paper,soil organic carbon was simulated in the next 50 years with CENTURY model in different climate scenarios at Damxung alpine meadow *** result shows that temperature and precipitation are the main contributor to the changes of soil organic *** in temperature and precipitation can reduce the accumulation of soil organic carbon resulting in the release of soil *** results are consistent in three climate change scenarios （temperature and precipitation increasing,temperature increasing and precipitation unchangeable,temperature unchangeable and precipitation increasing）.The content of soil organic carbon decreased,only slightly difference in extent in the three *** intensity was also a main factor to affect soil organic carbon and the influence on soil organic fractions was different.

关键词： soil organic carbon climate change CENTURY model alpine meadow

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Conjugacy Classes of Torsion in 4.4.Integral Symplectic Group

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Journal of Mathematical Research and Exposition 2008年第1期28卷 177-191页

作者： YANG Qing-jie Abstract A complete list of representatives of conjugacy classes of torsion in 4.x 4.integralsymplectic group is given in this paper. There are 55 distinct such classes and each torsionelement has order of 2, 3, 4. 5, 6, 8, 10 and 12. school of information ~ Renmin University of China Beijing 100872 China

A complete list of representatives of conjugacy classes of torsion in 4.4.integral symplectic group is given in this paper. There are 55 distinct such classes and each torsion element has order of 2, 3, 4. 5, 6, 8, 1... 详细信息

关键词： integral symplectic group torsion symplectic group space symplectic direct sum quasi-direct sum palindromic monic polynomial symplectic complement.

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