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基于TPM虚拟单调计数器的电子钱包方案的分析和扩展

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通信学报 2009年第S1期30卷 1-8页

作者：刘冬梅卿斯汉杨涛李小群中国科学院软件研究所基础软件国家工程研究中心北京100080 中国科学院研究生院北京100039 中国科学院软件研究所信息安全技术工程研究中心北京100080 中国科学院计算机网络信息中心e-science应用推进总体组北京100190

针对一种基于虚拟单调计数器的电子钱包方案存在的不足,对其进行了扩展,原方案商品原子性无法得到满足,且不能够防止货币消失的问题,即其货币原子性只能得到部分满足。在原方案的基础上,将货物的交换过程考虑进来,扩展后的方案既满足货... 详细信息

针对一种基于虚拟单调计数器的电子钱包方案存在的不足,对其进行了扩展,原方案商品原子性无法得到满足,且不能够防止货币消失的问题,即其货币原子性只能得到部分满足。在原方案的基础上,将货物的交换过程考虑进来,扩展后的方案既满足货币原子性,又满足商品原子性,同时能够为顾客提供隐私保护。

关键词：电子现金电子支付可信计算 TPM 公平性原子性匿名性

水产品中14种磺胺类药物残留的HPLC法同时测定

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分析测试学报 2004年第5期23卷 122-124页

作者：徐维海林黎明朱校斌王新亭中国科学院海洋研究所青岛出入境检验检疫局山东青岛266002

建立了HPLC法同时分离并检测鱼、虾等水产品中14种磺胺类抗菌药物。样品经无水硫酸钠脱水后 ,乙腈提取药物 ,再用乙腈饱和正己烷脱脂净化。以乙腈 -3 %冰醋酸为流动相 ,采用梯度淋洗 ,于268nm波长处检测。该法的检出限为0.01～0.02mg/k... 详细信息

建立了HPLC法同时分离并检测鱼、虾等水产品中14种磺胺类抗菌药物。样品经无水硫酸钠脱水后 ,乙腈提取药物 ,再用乙腈饱和正己烷脱脂净化。以乙腈 -3 %冰醋酸为流动相 ,采用梯度淋洗 ,于268nm波长处检测。该法的检出限为0.01～0.02mg/kg ,样品的加标回收率为66 %～92%。

关键词：高效液相色谱水产品磺胺类药物

Effects of cosmological constant on motion of UHECR particles

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science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 44-56页

作者： CHEN Shaoxia & CHANG Zhe Institute of High Energy Physics, chinese academy of sciences, beijing 100039, china graduate school of chinese academy of sciences, beijing 100039, china Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China graduate school Chinese Academy of Sciences Beijing 100039 China

Recent astronomical observations manifest that about two-thirds of the whole energy in the Universe is contributed by a small positive cosmological constant A (> 0). Then, an asymptotically de Sitter spacetime is premised naturally. However, physics in the de Sitter spacetime is very different from that in the Minkowski spacetime. As the first step, a covariant formalism of the kinematics in the de Sitter spacetime is presented here. By solving exactly the equations of motion for a field, we obtain the dispersion relation of a free particle. It is noticed that the dispersion relation is dependent on the degree of freedom of angular momentum of the particle. We show the threshold anomaly of the ultra high energy cosmic ray disappears naturally in the framework of the de Sitter kinematics.

关键词： ultrahigh energy cosmic ray, cosmological constant, curved spacetime.

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 100039, china) [a]chinese academy of sciences Institute of Automation Beijing China [b]graduate school of chinese academy of sciences Beijing 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.

Identification of the Angel -related elements in cyprinid fishes and their phylogenetic implications

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Progress in Natural science:Materials International 2007年第2期17卷 168-171页

作者： WANG Li, HE Shunping and CHEN Yiyu ( Institute of Hydrobiology, chinese academy of sciences, Wuhan 430072, china graduate school of the chinese academy of sciences, beijing 100039, china National Natural science Foundation of china, beijing 100085, china) [a]chinese academy of sciences Institute of Hydrobiology Wuhan China [b]graduate school of the chinese academy of sciences Beijing China [c]National Natural science Foundation of china Beijing China

Angel-related element belongs to the family of miniature inverted-repeat transposable elements (MITEs). In this paper we report the identification of an Angel- related element in the series Leuciscini of cyprinid fishes, which is located in the second intron of the growth hormone (GH) gene. We have also found that this element is absent in orthologous locus in the series Barbini of cyprinid fishes, that provides new evidence for the monophyly of the series Leuciscini. The insertion of Angel -related element into the GH gene might take place in the common ancestor of the series Leuciscini after its divergence from the series Barbini. The high sequence divergence and relatively broad species distribution of Angel-related elements implies that they might be ancient transposons which appeared about 26 million years ago.

关键词： Angel -related elements the series Leuciscini monophyly.

The deep thermal characteristic of continental margin of the northern South china Sea

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chinese science Bulletin 2000年第18期45卷 1717-1722页

作者： ZHANG Jian & WANG Jiyang1. graduate school, University of science and Technology of china, chinese academy of sciences, beijing 100039, china 2. Institute of Geology, chinese academy of sciences, beijing 100029, china graduate school University of Science and Technology of China Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Heat flow plays an important role in the study ot thermal structure and thermal evolutionof continental margin of the northern South china Sea. The analysis of heat flow value shows that margin heat flow in the northern South china Sea is relatively high setting, but the percentage of crustal heat flow is lower than 35% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the proportion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up of hot material from asthenosphere.

关键词： margin of northern South china Sea terrestrial heat flow thermal structures.

A NOTE ON THE CONSISTENCY OF LS ESTIMATES IN LINEAR MODELS

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chinese Annals of Mathematics,Series B 2001年第4期22卷 471-474页

作者： CHEN XIRU The graduate school at beijing, University of science and Technology of china, beijing 100039, china. The graduate school at beijing University of Science and Technology of China Beijing 100039 China

It is well known that when the random errors are iid. with finite variance, the week and the strong consiStency of LS estimate of multiple regression coefficients are equivalent. This note, by constructing a counter-example, shows that this equivalence no longer holds true in case that the random errors possess only the r-th moment with 1≤5 T ＜ 2.

关键词： Linear regression model Consistency LS estimate

Rate of strong consistency of quasi maximum likelihood estimate in generalized linear models

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science china Mathematics 2004年第6期47卷 882-893页

作者： YUE Li & CHEN Xiru school of Mathematics and Statistics, Wuhan University, Wuhan 430072, china graduate school, chinese academy of sciences, beijing 100039, china 1. school of Mathematics and Statistics Wuhan University 430072 Wuhan China 2. graduate school Chinese Academy of Sciences 100039 Beijing China

Under the assumption that in the generalized linear model (GLM) the expectation of the response variable has a correct specification and some other smooth conditions, it is shown that with probability one the quasi-likelihood equation for the GLM has a solution when the sample size n is sufficiently large. The rate of this solution tending to the true value is determined. In an important special case, this rate is the same as specified in the LIL for iid partial sums and thus cannot be improved anymore.

关键词： quasi-likelihood function generalized linear models strong consistency

Genetic fingerprinting of plankton community provides new insights into aquatic ecology

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Progress in Natural science:Materials International 2006年第9期16卷 893-898页

作者： YAN Qingyun, YU Yuhe and FENG Weisong ( Institute of Hydrobiology, chinese academy of sciences, Wuhan 430072, china graduate school of the chinese academy of Sci-ences, beijing 100039, china) [a]Institute of Hydrobiology Chinese Academy of Sciences Wuhan China [b]graduate school of the chinese academy of sciences Bejing China

Over the past two decades, molecular techniques have been widely used in ecological study and molecular ecology has been one of the most important branches of ecology. Meanwhile, genetic fingerprinting analyses have significantly enhanced our knowledge of the diversity and evolutionary relations of the planktonic organisms. Compared with conventional approaches in ecological study (e.g. morphological classification), genetic fingerprinting techniques are simpler and much more effective. This review provides an overview of the principles, advantages and limitations of the commonly used DNA fingerprinting techniques in plankton research. The aim of this overview is to assess where we have been, where we are now and what the future holds for solving aquatic ecological problems with molecular-level information.

关键词： genetic fingerprinting plankton community aquatic ecology genetic diversity.