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Privilege Flow Oriented Intrusion Detection Based on Hidden Semi-MarkovModel

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 137-141页

作者： ZHONG An-ming 1, JIA Chun-fu 1,21.College of information Technology and Sciences, Nankai University, Tianjin 300071,china 2.State Key Laboratory of information Security, institute of Software of chinese academy of Science, beijing 100039,china College of information Technology and Sciences Nankai University Tianjin 300071 China

A privilege flow oriented intrusion detection method based on HSMM (Hidden semi-Markov Model) is discussed. The privilege flow model and HSMM are incorporated in the implementation of an anomaly detection IDS (Intrusion Detection System). Using the dataset of DARPA 1998, our experiment results reveal good detection performance and acceptable computation cost.

关键词： Key words intrusion detection privilege flow model HSMM

A three-dimensional variational ocean data assimilation system:Scheme and preliminary results

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Science china Earth Sciences 2006年第11期49卷 1212-1222页

作者： ZHU Jiang1,2, ZHOU Guangqing1, YAN Changxiang1, FU Weiwei1 & YOU Xiaobao1,3 1. International Center for Climate and Environment Sciences, institute of Atmospheric Physics, chinese academy of Sciences, beijing 100029, china 2. Jiangsu Key Laboratory of Meteorological Disaster, Nanjing University of information Science and Technology, Nanjing 210044, china 3. beijing institute of Applied Meteorology, beijing 100029, china 1. International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Jiangsu Key Laboratory of Meteorological Disaster Nanjing University of Information Science and Technology Nanjing 210044 China 3. beijing institute of Applied Meteorology Beijing 100029 China

A new 3DVAR-based Ocean Variational Analysis System (OVALS) is developed. OVALS is capable of assimilating in situ sea water temperature and salinity observations and satellite altimetry data. As a component of OVALS, a new variational scheme is proposed to assimilate the sea surface height data. This scheme considers both the vertical correlation of background errors and the nonlinear temperature-salinity relationship which is derived from the generalization of the linear balance constraints to the nonlinear in the 3DVAR. By this scheme, the model temperature and salinity fields are directly adjusted from the altimetry data. Additionally, OVALS can assimilate the temperature and salinity profiles from the ARGO floats which have been implemented in recent years and some temperature and salinity data such as from expendable bathythermograph, moored ocean buoys, etc. A 21-year assimilation experiment is carried out by using OVALS and the Tropical Pacific circulation model. The results show that the assimilation system may effectively improve the estimations of temperature and salinity by assimilating all kinds of observations. Moreover, the root mean square errors of temperature and salinity in the upper depth less than 420 m reach 0.63℃ and 0.34 psu.

关键词： data assimilation, 3DVAR, sea surface height, ARGO floats.

Formation of Glycidyl Methacrylate-DNA Adducts in vivo

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Biomedical and Environmental Sciences 1999年第2期12卷 95-102页

作者： FANG FU-DE LEI HAI-XIN ZUO JIN TAN MING-JIA AND XU JIAN-NING (institute of Basic Medical Sciences, chinese academy of Medical Scicnces,beijing 100005, china Instituse of Occupational Medicine, chinese academy of Preverntive Medicine, beijing 100050, china) 中国医学科学院基础医学所北京 100005 中国预防医学科学院职业病医学所北京 100050 中国医学科学院基础医学所北京中国预防医学科学院职业病医学所北京

In in vivo test, rats were orally administrated with glycidyl methacrylate (GMA) at respective doses of 250 mg/kg, 125 mg/kg and 62. 5 mg/kg, 31. 25 mg/kg and solvent as control for 14 days. DNA adducts produced in the liver, kidney, blood and testis were analyzed by RP-HPLC and nuclease P1 mediated 32 P-postlabelling method. Results showed that several potential GMA-DNA adducts were formed in various organs (4 adducts in blood, 3 adducts in liver and kidney, 1 adduct in testis). A linear dose-response relationship was observed within certain dose levels. The relative adduct labeling values failed to further increase any more when the concentration went up to 125 mg/kg. The order of adduct level with GMA was kidney, liver, blood and testis. The GMA adduct N3methacrylate-2-hydroxypropyl-dCMP was found in kidney, liver and blood. These results indicated that GMA could react with negatively charged centers on DNA and form GMA-DNA adducts. If carcinogerrinduced DNA damage exceeds the ability of repair systems, gene mutation is ***, study on molecular mechanism of gene mutation induced by DNA adducts is not only an important part of chemical-carcinogenesis, but also provides information on critical biomarkers for monitoring human exposure to genetic toxins.

关键词： Animals Carcinogens DNA Adducts DNA Damage DNA Repair Dose-Response Relationship Drug Epoxy Compounds Male Methacrylates Mutagenesis Phosphorus Radioisotopes Rats Rats Wistar Research Support Non-U.S. Gov't

Arabian Peninsula-North Pacific Oscillation and its association with the Asian summer monsoon

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Science china Earth Sciences 2008年第7期51卷 1001-1012页

作者： SUN JianQi1, YUAN Wei2 & GAO YuZhong3 1 Nansen-Zhu International Research Centre, institute of Atmospheric Physics, chinese academy of Sciences, beijing 100029, china 2 china Meteorological Administration Training Centre, beijing 100081, china 3 Heilongjiang Meteorological Observatory, Harbin 150030, china 1. Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. china Meteorological Administration Training Centre Beijing 100081 China 3. Heilongjiang Meteorological Observatory Harbin 150030 China

Using correlation and EOF analyses on sea level pressure from 57-year NCEP-NCAR reanalysis data, the Arabian Peninsula-North Pacific Oscillation (APNPO) is identified. The APNPO reflects the co-variability between the North Pacific high and South Asian summer monsoon low. This teleconnec- tion pattern is closely related to the Asian summer monsoon. On interannual timescale, it co-varies with both the East Asian summer monsoon (EASM) and South Asian summer monsoon (SASM); on decadal timescale, it co-varies with the EASM: both exhibit two abrupt climate changes in the middle 1960s and the late 1970s respectively. The possible physical process for the connections between the APNPO and Asian summer monsoon is then explored by analyzing the APNPO-related atmospheric circulations. The results show that with a strong APNPO, the Somali Jet, SASM flow, EASM flow, and South Asian high are all enhanced, and an anomalous anticyclone is produced at the upper level over northeast china via a zonal wave train. Meanwhile, the moisture transportation to the Asian monsoon regions is also strengthened in a strong APNPO year, leading to a strong moisture convergence over India and northern china. All these changes of circulations and moisture conditions finally result in an anoma- lous Asian summer monsoon and monsoon rainfall over India and northern china. In addition, the APNPO has a good persistence from spring to summer. The spring APNPO is also significantly corre- lated with Asian summer monsoon variability. The spring APNPO might therefore provide valuable in- formation for the prediction of Asian summer monsoon.

关键词： Arabian Peninsula-North Pacific Oscillation East Asian summer monsoon South Asian summer monsoon wave train abrupt climate change

Application of the phylogenetic analysis in mitochondrial disease study

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chinese Science Bulletin 2008年第18期53卷 2733-2738页

作者： WANG ChengYe1,2,3, KONG QingPeng1,2 & ZHANG YaPing1,2? 1 State Key Laboratory of Genetic resources and Evolution, Kunming institute of Zoology, chinese academy of Sciences, Kunming 650223, china 2 Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming 650091, china 3 Graduate University of chinese academy of Sciences, beijing 100049, china chinese Acad Sci Kunming Inst Zool State Key Lab Genet Resources and Evolut Kunming 650223 Peoples R China.

Mitochondrial disease currently received an increasing concern. However, the case-control design commonly adopted in this field is vulnerable to genetic background, population stratification and poor data quality. Although the phylogenetic analysis could help solve part of these problems, it has not received adequate attention. This paper is a review of this method as well as its application in mito- chondrial disease study.

关键词：线粒体疾病分析单元型种群分布

information content security on the Internet:the control model and its evaluation

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Science china(information Sciences) 2010年第1期53卷 30-49页

作者： FANG BinXing1, GUO YunChuan2,3 & ZHOU Yuan4 1School of Computer, beijing University of Posts and Telecommunications, beijing 100029, china 2institute of Computing Technology, chinese academy of Sciences, beijing 100190, china 3Graduate University of chinese academy of Sciences, beijing 100049, china 4National Computer Network Emergency Response Technical Team/Coordination Center of china, beijing 100029, china 1. School of Computer Beijing University of Posts and Telecommunications Beijing 100029 China2. Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China4. National Computer Network Emergency Response Technical Team/Coordination Center of China Beijing 100029 China

Flooding of harmful information on the Internet seriously endangers the physiological and mental health of teenagers. Due to the user-friendliness of the Internet as well as the difficulty in the authentication for the access of specific categories of information, curbing the transmission of harmful information, i.e., assuring the information content security (ICS), has become a reasonable yet challenging alternative. At present, there is an urgent need to develop a systematic model that can effectively carry out the curbing. In fact, curbing the transmission of harmful information by way of filtering can be modeled by access control. In the paper, based on the three core-elements of communication, namely, "Who communicates with whom", "How do they communicate" and "What is the content of communication", we propose a control model, called ICCON. Unlike the existing access control, the reference monitor (RM) of our model is placed in the transmission channel, and moreover, an evaluation frame is proposed, through which the effectiveness of the RM in controlling information transmission on the Internet can be quantitatively evaluated.

关键词： content security access control quantitative evaluation

Speciation of the genus Arthricocephalus Bergeron, 1899 (Trilobita) from the late Early Cambrian and its stratigraphic significance

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Progress in Natural Science:Materials International 2006年第6期16卷 614-623页

作者： YUAN Jinliang, ZHAO Yuanlong and YANG Xinglian (Nanjing institute of Geology and Palaeontology, chinese academy of Sciences, Nanjing 210008, china College of resource and Environment of Guizhou University, Guiyang 550003, china) [a] Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China [b] College of resource and Environment of Guizhou University Guiyang China

The genus Arthricocephalus Bergeron, 1899 is revised, and Halipanktos Balker & Peel, 1997 is suggested here as a senior synonym. The subgenus Arthricocephalus (Arthricocephalites) Chien & Lin in Lu et al. , 1974 is considered as a separate genus. Of the 20 previously assigned species of Arthricocephaius (Arthricocephalus) Bergeron, 1899, Arthricocephalus (Arthricocephalites) Chien & Lin in Lu et al. , 1974, Arthricocephalus (Euarthricocephalus) Ju, 1983 are lumped into eight species. The speciation trend of Arthricocephalus and Arthricocephalites is demonstrated based on their stratigraphic occurrences. It not only enhances the resolution of the biostatigraphic zonation in the uppermost Lower Cambrian, but also represents a potential candidate to define the Duyunian stage. The base of the stage is suggested at the first appearance datum (FAD) of Arthricocephalus chauveaui Bergeron, 1899 within the evolutionary lineage from Ar. jiangkouensis Yin in Yin & Li, 1978 to Ar. chauveaui in a global scale.

关键词： late Early Cambrian Duyunian stage speciation of Arthricocephalus and Arthricocephalites biostratigraphy.

Negative refraction in two-dimensional photonic crystals

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Progress in Natural Science:Materials International 2006年第10期16卷 1027-1032页

作者： REN Xiaobin, REN Kun, FENG Zhifang, FENG Shuai and REN Cheng ( School of Physics Science and information Technology, Liaocheng University, Liaocheng 252059, china beijing National Laboratory for Condensed Matter Physics, institute of Physics, chinese academy of Sciences, beijing 100080, china) [a]School of physics Science and information Techonolgy Liaocheng University Liaocheng China [b]beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China

Recent progress made in research on negative refraction in two-dimensional photonic crystals is reviewed. Special attentions are paid to the research results of our group. We explore the underlying mechanism governing the occurrence of negative refraction in periodic and quasiperiodic photonic crystals. These results may be useful references for the application of photonic crystals. The perspectives of future research on negative refraction are briefly predicted.

关键词： negative refraction photonic crystals superlens subwavelength imaging equifreqnency surface.

A study on the early-warning technique concerning debris flow disasters

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Journal of Geographical Sciences 2002年第3期12卷 363-370页

作者： ZHOU Jinxing, WANG Lixian, XIE Baoyuan, FEI Shimin, WANG Xilin (1. Inst. of forestry Research, chinese academy of forestry Science, beijing 100091, china 2. College of resource & Environment, beijing forestry University, beijing 100083, china) Inst of Forestry Research Chinese Academy of Forestry Science 北京 100091 College of resource & Environment Beijing Forestry University 北京 100083

According to the principle of the eruption of debris flows, the new torrent classification techniques are brought forward. The torrent there can be divided into 4 types such as the debris flow torrent with high destructive strength, the debris flow torrent, high sand-carrying capacity flush flood torrent and common flush flood by the techniques. In this paper, the classification indices system and the quantitative rating methods are presented. Based on torrent classification, debris flow torrent hazard zone mapping techniques by which the debris flow disaster early-warning object can be ascertained accurately are identified. The key techniques of building the debris flow disaster neural network (NN) real time forecasting model are given detailed explanations in this paper, including the determination of neural node at the input layer, the output layer and the implicit layer, the construction of knowledge source and the initial weight value and so on. With this technique, the debris flow disaster real-time forecasting neural network model is built according to the rainfall features of the historical debris flow disasters, which includes multiple rain factors such as rainfall of the disaster day, the rainfall of 15 days before the disaster day, the maximal rate of rainfall in one hour and ten minutes. It can forecast the probability, critical rainfall of eruption of the debris flows, through the real-time rainfall monitoring or weather forecasting. Based on the torrent classification and hazard zone mapping, combined with rainfall monitoring in the rainy season and real-time forecasting models, the debris flow disaster early-warning system is built. In this system, the GIS technique, the advanced international software and hardware are applied, which makes the system’s performance steady with good expansibility. The system is a visual information system that serves management and decision-making, which can facilitate timely inspect of the variation of the torrent type

关键词： debris flows disaster early-warning technique torrent classification mapping of the hazard zones