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DNS服务中的Internet访问行为测量研究

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计算机工程与应用 2009年第34期45卷 85-88,106页

作者：尉迟学彪李晓东阎保平季成中国科学院计算机网络信息中心北京100190 中国科学院研究生院北京100049 清华大学电子工程系复杂工程系统实验室北京100084

借助于中国互联网络信息中心负责管理的国家顶级域名系统资源,对当前CN顶级域名DNS服务请求进行了宏观测量和分析。研究发现,CN国家域名整体查询频度特征服从类Zipf’s分布,递归服务器域名查询量遵从广延指数分布,即CN国家域名的DNS服... 详细信息

借助于中国互联网络信息中心负责管理的国家顶级域名系统资源,对当前CN顶级域名DNS服务请求进行了宏观测量和分析。研究发现,CN国家域名整体查询频度特征服从类Zipf’s分布,递归服务器域名查询量遵从广延指数分布,即CN国家域名的DNS服务请求具有整体集中分布的特征和域名查询模式的时间局部特征。这些关于国家域名服务的整体认识和全局性描述对于深入了解我国国家域名系统的整体运行状况,科学认识我国宏观网络发展特征具有重要意义。

关键词： DNS查询宏观网络分析 Zipf's定律广延指数分布 CN国家顶级域

Effect of temperature and light intensity on the growth and reproduction of the green macroalga,Chaetomorpha valida（Cladophoraceae,Chlorophyta）

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Effect of temperature and light intensity on the growth and ...

中国藻类学会第八次会员大会暨第十六次学术讨论会

作者： Yunyan Deng~(1,2),Xiaorong Tang~3,Bingxin Huang~4 and Lanping Ding~(1,4) 1.Institute of Oceanology,chinese academy of sciences,Qingdao 266071,china 2.graduate university of chinese academy of sciences,beijing 100049,china 3.Key Laboratory of Marine Genetics and Breeding(Ocean university of china),Ministry of Education,Qingdao 266003,china 4.Shantou university,Shantou 515063,china

＜正＞Chaetomorpha valida（Hooker et Harvey） Kützing（Cladophoraceae,Chlorophyta）,as a fouling green alga,was found in aquaculture ponds in coastal cities of Dalian and Rongcheng in china recent *** abundances of t...

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iTRAQ based quantitative analysis of endogenous peptides from Caenorhabditis elegans

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iTRAQ based quantitative analysis of endogenous peptides fro...

第十七届国际生物物理大会;第十二届中国生物物理大会

作者： Tanxi Cai~(1,2),Jing Li~1,Junjie Hou~1,Zhengsheng Xie~3,Peng Xue~1,Xiulan Chen~1,Peng Wu~3,Tao Xu~1, Fuquan Yang~3 1.Center for System Biology,Institute of Biophysics,chinese academy of sciences,beijing,P.R.china 2.graduate university of the chinese academy of sciences,beijing,P.R.china 3.Proteomic Platform,Institute of Biophysics,chinese academy of sciences,beijing,P.R.china

Neuropeptides function in a multitude of behaviors in Caenoharbditis elegans,including dauer formation, locomotion,egg-laying,and mechano- and *** studies use mass spectrometry, which aims at the simultaneous visualiz... 详细信息

关键词： C.elegans quantitative neuropeptides iTRAQ

3D Nerve: A Three-Dimensional Reconstruction System for Peripheral Nerves

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3D Nerve: A Three-Dimensional Reconstruction System for Peri...

2008 IEEE International Symposium on IT in Medicine and Education(ITME 2008)

作者： Ping Hu 1 2 Shuisheng Xie 1 2 Juan Ge 1 2 Liyan Liu 1 2 Shaorong Wang 1 2 Fucang Jia 1 2 Zongkai Lin 1 2 Hua Li 1 2 Kuo Sun 3 Zenggan Chen 3 Jian Zhang 3 1.National Research Center for Intelligent Computing Systems Institute of Computing Technology chinese academy of sciences beijing 100190 china 2.graduate university of chinese academy of sciences beijing 100049 china 3.Zhongshan Hospital Fudan university Shanghai 200032 china

Repair and regeneration of injured peripheral nerves have always been a focus in the field of *** nerve atlas contains only two-dimensional information and can’t display the real cross and recombination process of nerve bundles in its whole *** solve this problem,a system,3D Nerve,is proposed for the 3D reconstruction of peripheral *** image registration,image segmentation,contour correspondence and surface reconstruction process,this system successfully represents the topographic anatomy of every nerve fascicle and its relationship with the nicety localization information of sense fibers and motor ones in arbitrary *** is a great help for clinical peripheral nerve repair and 3D peripheral nerve teaching.

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Influenza virus detection with pentabody-activated nanoparticles

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Influenza virus detection with pentabody-activated nanoparti...

第十七届国际生物物理大会;第十二届中国生物物理大会

作者： Bin Mu~(1,2),Xinglu Huang~3,Pengcheng Bu~1,Jie Zhuang~(1,2),Zhixue Cheng~3,Jing Feng~1,Dongling Yang~1, Changsheng Dong~3,Jianbing Zhang~4,Minmin Liang~1,Xiyun Yan~1 1.National Laboratory of Biomacromolecules,Institute of Biophysics,chinese academy of sciences,beijing, china 2.graduate university of the chinese academy of sciences,beijing,china

Ananoparticle-based immunoassaywas developed for the rapid and sensitive detectionof avianinfluenza virus (AIV).In thismethod,AlV-specific pentabody(pVHH3B) was conjugated tomagnetic nanoparticles(MNPs) and

关键词： Immunoassay Pentabody Magnetic nanoparticles Gold nanoparticles

Upper Mantle Transitional Zone beneath Central-Southern Tibet

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Upper Mantle Transitional Zone beneath Central-Southern Tibe...

中国地球物理学会第二十七届年会

作者： Junmeng Zhao~(1,*) Ying Huang~(1,2) Shunping Pei~1 Hongbing Liu~1 Wei Wang~1 Qiang Xu~1 Honggang Cheng~1 Wei Tang~1 Lei Yang~1 1.Laboratory of Continental Collision and Plateau Uplift,Institute of Tibetan Plateau Research, chinese academy of sciences,beijing,100085,P.R.china 2.graduate university of the chinese academy of sciences,beijing,100049,P.R.china

＜正＞*** The Tibetan Plateau is the result of the collision between India and Eurasia,which began at approximately 50 Ma（Yin and Harrison,2000）.Over the past several decades,numerous international seismic experiments have been undertaken in Tibet to study the crustal and mantle structure of the ***,different mechanisms have been put forward to explain the evolution of the Tibetan plateau and adjacent *** fully understand the geodynamics of the India-Eurasia collision requires seismic investigation of lithospheric deformation of the *** of the best ways to image deformation in Earth’s interior is through the detection and interpretation of seismic *** anisotropy can give us insight into the past and current mantle

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兰州重离子加速器冷却储存环电子冷却高压电源

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电源技术应用 2011年第2期14卷 26-30页

作者：马晓明杨晓东冒立军李杰李国宏唐勇晏太来中国科学院近代物理研究所甘肃兰州730000 中国科学院研究生院北京100049

介绍了兰州重离子加速器冷却储存环(HIRFL-CSR)电子冷却装置电源系统,对其中300kV高压电源做了详细介绍,通过测试研究了高压稳定性。

关键词：电子冷却半桥功率变换器

Observation results of relativistic electrons detected by Fengyun-1 satellite and analysis of relativistic electron enhancement (REE) events

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Science china(Physics,Mechanics & Astronomy) 2008年第12期51卷 1947-1956页

作者： YANG XiaoChao1,2↑ & WANG ShiJin1 1 Center for Space Science and Applied Research, chinese academy of sciences, beijing 100190, china 2.graduate university of chinese academy of sciences, beijing 100049, china Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China

The space particle component detector on Fengyun-1 satellite which works at the sun-synchronous orbit of about 870 km altitude has detected relativistic electrons for a long time. In comparison with the SAMPEX satellite observations during 1999–2004, the relativistic electron data from Fengyun-1 satellite from June 1999 to 2005 are used to analyze the relativistic electron enhancement (REE) events at the low earth orbit, and the possible correlation among REE events at the low earth orbit, high-speed solar wind and geomagnetic storms is discussed. The statistical result presents that 45 REE events are found in total during this time period, and the strong REE events with the maximum daily average flux > 400 cm?2·srt-1·s?1 occur mostly during the transition period from solar maximum to solar minimum. Among these 45 REE events, four strong REE events last a longer time period from 26-to 51-day and correlate closely with high speed solar wind and strong geomagnetic storms. Meanwhile, several strong geomagnetic storms occur continuously before these REE events, and these continuous geomagnetic storms would be an important factor causing these long-lasting strong REE events. The correlation analysis for overall 45 events indicates that the strength of the REE events correlates with the solar wind speed and the strength of the geomagnetic storm, and the correlation for strong REE events is much stronger than that for weak REE events.

关键词： relativistic electron enhancement low earth orbit high-speed solar wind geomagnetic storm

Ionization state of cosmic hydrogen by early stars and quasars

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Research in Astronomy and Astrophysics 2009年第6期9卷 665-681页

作者： Xiao-Chun Mao1,2 1 National Astronomical Observatories, chinese academy of sciences, beijing 100012, china 2.graduate university of chinese academy of sciences, beijing 100049, china National Astronomical Observatories Chinese Academy of Sciences graduate university of chinese academy of sciences

Cosmic hydrogen is reionized and maintained in its highly ionized state by the ultraviolet emission attributed to an early generation of stars and quasars. The Lyα opacity observed in absorption spectra of high-redshift quasars permits more stringent constraints on the ionization state of cosmic hydrogen. Based on density perturbation and structure formation theory, we develop an analytic model to trace the evolution of the ionization state in the post-overlap epoch of reionization, in which the bias factor is taken into account. For quasars, we represent an improved luminosity function by utilizing a hybrid approach for the halo formation rate that is in reasonable agreement with the published measurements at 2 ≤ z ≤ 6. Comparison with the classic Press-Schechter mass function of dark matter halos, we demonstrate that the biased mass distribution indeed enhances star formation efficiency in the overdense environment by more than 25 per cent following the overlap of ionized bubbles. In addition, an alternative way is introduced to derive robust estimates of the mean free path for ionizing photons. In our model, star-forming galaxies are likely to dominate the ionizing background radiation beyond z = 3, and quasars contribute equally above a redshift of z ～ 2.5. From 5 ≤ z ≤ 6, the lack of evolution in photoionization rate can thus be explained by the relatively flat evolution in star formation efficiency, although the mean free path of ionizing photons increases rapidly. Moreover, in the redshift interval z ～ 2 - 6, the expected mean free path and Gunn-Peterson optical depth obviously evolve by a factor of ～ 500 and ～50 respectively. We find that the relative values of critical overdensities for hydrogen ionization and collapse could be 430% at z ≈2 and 2% at z ≈6, suggesting a rapid overlap process in the overdense regions around instant quasars following reionization. We further illustrate that the absolute estimates of the fraction of neutral hydrogen computed fr

关键词： cosmology theory -- formation galaxies -- quasars general -- diffuse radiation -- intergalactic medium