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Identifying heavy hitters in high-speed network monitoring

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Science China(Information Sciences) 2010年第3期53卷 659-676页

作者： ZHANG Yu1, FANG BinXing1,2.& ZHANG YongZheng2.1Research Center of Computer Network and Information Security Technology, Harbin institute of Technology, Harbin 150001, China 2.esearch Center of Information Security, institute of {2. Technology, Chinese Academy of Sciences, Beijing 100190, China 1. Research Center of Computer Network and Information Security Technology Harbin Institute of Technology Harbin 150001 China2. Research Center of Information Security Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China

Identifying heavy hitters in a network traffic stream is important for a variety of network applications ranging from traffic engineering to anomaly detection such as detection of denial-of-service attacks. Existing methods generally examine newly arriving items in the stream, perform a small number of operations using a small amount of memory, and still provide guarantees on the identifying accuracy. In high-speed network monitoring, the update speed per item is extremely critical. However, so far as we know, there are no identifying algorithms which can provide constant update time (O(1)) in a weighted data stream. In this paper, we present an algorithm named Weighted Lossy Counting (WLC) which is able to identify heavy hitters in a high-speed weighted data stream with constant update time. WLC employs a novel efficient partially ordered data structure which is able to provide a fast per-item update speed while keeping the memory cost relatively low. We compare WLC with state-of-the-art algorithms for finding heavy hitters in real traffic traces. The experimental results show that WLC performs well in accuracy (recall, precision and average relative error) as other algorithms; moreover it has a much higher update speed at the cost of relatively larger memory space used. A theoretical worst-case memory bound of WLC is also derived in this paper; however, experiments with long real traffic traces show that WLC requires much less space than the theoretical bound in practice.

关键词： network traffic monitoring heavy hitter weighted data streams

A good example of high-energy radiation delay event

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Chinese Science Bulletin 1997年第4期42卷 313-315页

作者： GAN Weiqun and Rieger Erich1 Purple Mountain Observatory, Nanjing 2.0008, China 2. Max-Planck institute of Extraterrestrial Physics, Garching 85740,Germany Purple Mountain Observatory Nanjing China Max-Planck institute of Extraterrestrial Physics Garching Germany

THE delay of high-energy radiation of solar flares can be divided into two types: one is the energy-dependent delay in the hard X-ray regime, the other is the delay between the hard X-rays and instantaneous γ-ray line (GRL) emissions. Both types have different physical meanings. The former reflects the difference in acceleration or transportation of energetic electrons with various energies, while the latter reflects such a difference between the energetic electrons

关键词： sun. flare X-ray γ-ray.

Technical development of proteomics

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Chinese Science Bulletin 1999年第16期44卷 1441-1447页

作者： WAN Jinghong and HE Fuchu1.Chongqing Medical University, Chongqing 400046, China 2. Beijing institute of Radiation Medicine, Beijing 100850, China Corresponding author Chongqing Medical University Chongqing China Beijing institute of Radiation Medicine Beijing China

Proteome research is an important complementarity for the genome research, which uses quantitative protein-level measurements to characterize biological process. Proteome techniques include two aspects. One is two-dimensional electrophoresis, which is the unique technology to separate the components of proteome. The other is identification of the

关键词： proteome two-dimensional electrophoresis image analysis peptide-mass fingerprinting database.

Biological aspects on the cultures of the entomophthoralean fungus Pandora delphacis grown on broomcorn millets

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Science Bulletin 2003年第17期48卷 1816-1821页

作者： FENG Mingguang1,2.& LIANG Yong1 1. institute of Microbiology, College of Life Sciences, Zhejiang Univer-sity, Hangzhou 31002., China 2. institute of Applied Entomology, College of Agricultural Sciences and Biotechnology, Zhejiang University, Hangzhou 31002., China institute of Microbiology College of Life Sciences Zhejiang University Hangzhou 310029 China

A novel method was developed to use glutinous broomcorn millets (Panicum miliaceum L.) as solid substrate to make cultures of the entomophthoralean fungus Pandora delphacis specifically pathogenic to planthoppers, leafhop-pers and aphids. Steamed millets with water content of 45% were inoculated with a liquid culture of P. delphacis at a ratio of 2.% (v/w) and then incubated at 2.℃ and L:D 12.12. The millets cultured for 3—17 d exhibited high potential for co-nidial production. The 5-d-old millet culture sporulated most abundantly, discharging up to 17.12.(1.31) 104 conidia/ millet. The cultures incubated for 7—11 d also had a satis-factory sporulation capability, yielding 13.00—13.90 104 conidia/millet. Compared to 2.32.(0.34) 104 conidia dis-charged from each of Myzus persicae adults killed by P. del-phacis and a ≤60-h duration of sporulation, each of the millets cultured for 5—11 d produced 5.6—7.4 times more conidia with an over doubled duration for conidial discharge (144 h). Among 106 M. persicae adults exposed to the shower of conidia discharged from the cultured millets, a total mor-tality of 69.8% caused by P. delphacis infection was observed within 7 d after exposure, but no death was attributed to the fungal infection in the aphids unexposed. The results indi-cate that the millet cultures of P. delphacis are biologically similar to aphid cadavers killed by the same fungus. Due to the superiority of the cultured millets to the cadavers in sporulation potential and duration, the method for making cultures of P. delphacis on the broomcorn millets is highly recommended for use in study of entomophthoralean fungi for microbial control. This is the first report on the success of the solid culture of Pandora species on cereals.

关键词： entomophthorales Pandora delphacis broomcorn millets solid culture sporulation capability aphid infectivity.

Slope safety control during mining below a landslide

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Science China(Technological Sciences) 2005年第z1期48卷 47-52页

作者： MIN Hong1, DENG Jianhui1, WEI Jinbing1, ZHANG Qizhong2. ZOU Jiangang2.& ZHOU Zhibin2.1. institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China 2. Daye Iron Mine of WISCO, Tieshan, Daye 435006, China Chinese Acad Sci Inst Rock & Soil Mech Wuhan 430071 Peoples R China WISCO DAye Iron Mine Daye 425006 Peoples R China

The East Open Pits of Daye Iron Mine were closed in year 2.00 and the ore beyond the pit limit was planned to be mined by underground ways. In order to facilitate the smooth transition to underground mining, hanging-wall ores in the old pits were scheduled to be mined. Xiangbishan pit is one of the four mining spots selected. In 1979 when the pit was mined to around 36 m a.s.l., a landside of around 70000 m3 occurred in its North Slope, leading to the closure of the pit. The pit was then backfilled to 60 m a.s.l. to maintain the slope stability. The hanging-wall ore to be mined is just located below the old slide, so whether the slide will be reactivated and how to control its deformation and stability are the key issues concerned. Based on geological investigation and numerical analysis, it was predicted that the slide would be reactivated and a control measure using the intact ore body as a retaining wall was thus suggested. During mining, displacements were monitored to assure safety. By July, 2.03, 383000 tons of ore were successfully mined. Though the observed displacement reached 8795 mm, no major failure happened. The final slope is 110 m high with an angle of 70°.

关键词： open pit mine, hanging-wall ore mining, landslide, control measure, retaining wall.

Recent Beijing Spectroscopy (BES) results

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Science China(Physics,Mechanics & Astronomy) 2008年第6期51卷 567-576页

作者： LI WeiGuo institute of high Energy Physics, Chinese Academy of Sciences, Beijing 100049, China 1. institute of high Energy Physics Chinese Academy of Sciences Beijing 100049 China

Recent experimental results from Beijing Spectroscopy (BES) are reviewed, including the hadron spectroscopy from J/ψ decays, and a number of new states are found or confirmed, including σ, κ, X(1835), ωφ threshold enhancement in J/ψ→γωφ, a broad resonance in J/ψ→K + K ? π 0, decay studies of ψ(2.) and χ CJ , as well as the results of ψ(3770) non-D $ \bar D $ decays. The current status of BEPCII/BESIII, the major upgrade of BEPC/BESII, is also reported.

关键词： Beijing Spectroscopy hadron spectroscopy charm physics BEPCII

Formation of complexes of Rubisco-Rubisco activase from La^3+, Ce^3+ treatment spinach

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Science China Chemistry 2005年第1期48卷 67-74页

作者： HONG Fashui1, LIU Chao1, ZHENG Lei1, WANG Xuefeng1, WU Kang1, SONG Weiping1, Lü Shipeng1, TAO Ye2.& ZHAO Guiwen3 1. College of Life Sciences, Suzhou Universty, Suzhou 2.5006, China 2. Synchrotron Radiation Laboratory, institute of high Energy Physics, The Chinese Academy of Science, Beijing 100039, China 3. Chemical Department, University of Science and Technology of China, Hefei 2.002., China 1. College of Life Sciences Suzhou Universty 215006 Suzhou China 2. Synchrotron Radiation Laboratory Institute of High Energy Physics The Chinese Academy of Science 100039 Beijing China 3. Chemical Department University of Science and Technology of China 230026 Hefei China

The complex of Rubisco and Rubisco activase from LaCl3-, CeCl3- treated spinach in vivo is induced. SDS-PAGE result shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only large and small subunits (55 kD, 14.4 kD) of Rubisco, but also two large subunits of 45 kD and 41 kD near the large subunits of Rubisco. Native-PAGE shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only a band of Rubisco (560 kD), but also a band of about 1100 kD, about twice distant from Rubisco, which might be a complex of Rubisco and Rubisco activase. The purified enzyme activities from LaCl3-, CeCl3-treated spinach are 1.8 and 2.8 times that of the control,the intensities of absorption and fluorescence are sig- nificantly higher than that of the purified Rubisco from the control, and the total sulfhydryl groups and available sulfhydryl groups are 36—39 –SH per mol enzyme, 14—2. –SH per mol enzyme more than those of the purified Rubisco from the control, respectively. The CD spectra show that the secondary structure of the purified enzyme from LaCl3-, CeCl3 -treated spinach is very dif- ferent from the control. The enzyme activities from LaCl3-, CeCl3- treated spinach in vivo are 1.5 and 1.9 times those of the control.

关键词： La3+, Ce3+, spinach, Rubisco, complex of Rubisco and Rubisco acitivase, spectral characteristics.

The third waves of genomics

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The third waves of genomics

Plus cupping degrees do not form an ideal

第十三届全国植物基因组学大会

作者： Yijun Ruan Huazhong Agricultural University and the Genome institute of singapore

high throughput DNA sequencing technology and the reference genome sequences of human and model organisms signify a significant revolution in modern *** comprehensive linear one-dimensional(1D) genome information dramatically changed our views and ways of conducting biological *** momentum of the first waves of genomics leaded to the second waves of genomics prompted by

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来源： cnki会议评论

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Science in China(Series F) 2004年第5期47卷 635-654页

作者： LI Angsheng1,2.& ZHAO Yicheng1 1. institute of Software,Chinese Academy of Sciences,Beijing 100080,China 2. School of Information Sciences,Beijing Normal University,Beijing 100871,China 1. institute of Software Chinese Academy of Sciences 100080 Beijing China 2. School of Information Sciences Beijing Normal University 100871 Beijing China

A computably enumerable (c.e.,for short)degree a is called plus cupping,if every c.e. degree x with 0 详细信息

A computably enumerable (c.e.,for short)degree a is called plus cupping,if every c.e. degree x with 0high degree. So by the Harringtons noncupping theorem,PC is not an ideal of ε.

关键词： computably enumerable set Turing degree definability.