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Preliminary study on assessment of nutrient transport in the Taihu Basin based on SWAT modeling

Science china Earth Sciences 2006年第Z1期49卷 135-145页

作者： LAI Geying, YU Ge & GUI Feng Nanjing institute of Geography & Limnology, chinese academy of Sciences, Nanjing 210008, china The Graduate School of the chinese academy of Sciences, beijing 100039, china Key Lab of Poyang Lake Ecological Environment and resource Development, Jiangxi Normal University, Nanchang 330027, china Nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing China The Graduate School of the chinese academy of Sciences Beijing China Key Lab of Poyang Lake Ecological Environment and resource Development Jiangxi Normal University Nanchang China

With the Taihu Basin as a study area, using the spatially distributed and mechanism-based SWAT model, preliminary simulations of nutrient transport in the Taihu Basin during the period of 1995～2002 has been carried out. The topography, soil, meteorology and land use with industrial point pollution discharge, the loss of agricultural fertilizers, urban sewerage, and livestock drainages were all considered in the boundary conditions of the simulations. The model was calibrated and validated against water quality monitoring data from 2001 to 2002. The results show that the annual total productions of nitrogen (TN) and phosphorus (TP) into Lake Taihu are 40000t and 2000t respectively. Nutrient from the Huxi Region is a major resource for Lake Taihu. The non-point source (surface source) pollution is the main form of catchment sources of nutrients into Lake Taihu,occupied TN 53% and TP 56% respectively. TN and TP nutrients from industrial point pollution discharge are 30% and 16%, and sewerage in both forms of point source and non-point source are TN 31% and TP 47%. Both the loss of agricultural fertilizers and livestock drainages from the catchment should be paid more attention as an important nutrient source. The results also show that SWAT is an effective model for the simulation of temporally and spatially nutrient changes and for the assessment of the trends in a catchment scale.

关键词： Taihu Basin, nutrients, catchment resource inputs, SWAT model, simulation.

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Neutron and density logging responses to gas reservoir for well-balanced and under-balanced logging:Gas reservoirs of sandstone in a western china field

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Science china Earth Sciences 2008年第S2期51卷 201-206页

作者： WU WenSheng1,XIAO LiZhi1 & ZHANG LongHai2 1 resource & information Department,china University of Petroleum,beijing 102249,china 2 research institute of Petroleum Exploration and Development,Petrochina,beijing 100083,china resource & information Department China University of Petroleum Beijing China research institute of Petroleum Exploration and Development PetroChina Beijing China

Studying the response differences between neutron and density logging of gas reservoir for well-balanced and under-balanced logging will be of significance in evaluation of gas reservoir under the under-balanced condition and application of logging data. With Monte Carlo simulation technique,the paper obtains the relationship between neutron and density logging measurement and borehole di-ameter,porosity or gas saturation for well-balanced and under-balanced logging. The conclusions show that the response trend of under-balanced logging to gas reservoirs agrees with that of well-balanced logging with small borehole,and under-balanced logging data can be used usually as well-balanced logging data. When borehole diameter is large,under-balanced logging data should be corrected for the influences of borehole.

关键词： under-balanced logging density logging neutron logging gas reservoir response

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The Role of Sciencein Codex Standards

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Biomedical and Environmental Sciences 2001年第1期14卷 145-148页

作者： CHEN JUN SHI institute of Nutrition and Food Hygiene, chinese academy of Preventive Medicine, beijing 100050, china 中国预防医学科学院营养与食品卫生所北京 100050

The key principle in the development of Codex standards is to ensure that the decision making process is based on sound science. The approval for the use of food additives and other chemicals in foods should be made only when adequate scientific data is available. The same principle applies to the development of maximum tolerable (or residue) levels for contaminants in foods. Using the General Standards for Contaminants and Toxins in Foods as an example, the following criteria are considered, when developing recommendations and standards: Toxicological information; Analytical data; Intake data; Fair trade considerations; Technological considerations; and Risk assessment and risk management considerations. The Codex Alimentarius Commission has repeatedly emphasized the use of risk analysis approach, in particular the use of risk assessment in conducting the safety evaluation of food additives, agricultural and veterinary chemicals and environmental and industrial contaminants in foods. In this respect, the well known efforts of the FAO/WHO Joint Expert Committee on Food Additives (JECFA) and the FAO/WHO Joint Meeting on Pesticide Residues (JMPR) provide the much needed information and recommendations for the risk assessment of specific chemicals. The risk assessment approach is also used in the safety evaluation of foods derived from modern biotechnology as well as in the quantitative assessment of microbiological risks in foods.

关键词： JECFA The Role of Sciencein Codex Standards

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Perceptual video hashing robust against geometric distortions

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Science china(information Sciences) 2012年第7期55卷 1520-1527页

作者： XIANG ShiJun 1,4 ,YANG JianQuan 2 & HUANG JiWu 3 1 School of information Science and technology,Jinan University,Guangzhou 510632,china 2 Shenzhen institutes of Advanced technology,chinese academy of Sciences,Shenzhen 518055,china 3 School of information Science and technology,Sun Yat-sen University,Guangzhou 510275,china 4 State Key Laboratory of information Security,institute of Software,chinese academy of Sciences,beijing 100049,china School of information Science and technology Jinan University Guangzhou China State Key Laboratory of information Security Institute of Software Chinese Academy of Sciences Beijing China Shenzhen institutes of Advanced technology Chinese Academy of Sciences Shenzhen China School of information Science and technology Sun Yat-sen University Guangzhou China

In this paper,we propose a robust perceptual hashing algorithm by using video luminance histogram in *** underlying robustness principles are based on three main aspects:1) Since the histogram is independent of position of a pixel,the algorithm is resistant to geometric deformations; 2) the hash is extracted from the spatial Gaussian-filtering low-frequency component for those common video processing operations such as noise corruption,low-pass filtering,lossy compression,etc.; 3) a temporal Gaussian-filtering operation is designed so that the hash is resistant to temporal desynchronization operations,such as frame rate change and *** a result,the hash function is robust to common geometric distortions and video processing *** results show that the proposed hashing strategy can provide satisfactory robustness and uniqueness.

关键词： video hashing geometric distortion histogram Gaussian filtering

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Growth characteristics and response to climate change of Larix Miller tree-ring in china

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Science china Earth Sciences 2010年第6期53卷 871-879页

作者： SUN Yu1,4, WANG LiLi1,2,3, CHEN Jin5, DUAN JianPing1,4, SHAO XueMei1,2 & CHEN KeLong6 1 institute of Geographic Sciences and Natural resources research, chinese academy of Sciences, beijing 100101, china 2 institute of Tibetan Plateau research, chinese academy of Sciences, beijing 100085, china 3 institute of Desert and Meteorology, china Meteorological Administration, Urumqi 830002, china 4 Graduate University of chinese academy of Sciences, beijing 100049, china 5 institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of Sciences, beijing 100044, china 6 School of Life and Geography Sciences, Qinghai Normal University, Xining 810008, china institute of Geographic Sciences and Natural resources research Chinese Academy of Sciences Beijing China Graduate University of chinese academy of Sciences Beijing China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China institute of Desert and Meteorology China Meteorological Administration Urumqi China institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China School of Life and Geography Sciences Qinghai Normal University Xining China

As one of the earliest species used in dendrochronological studies, Larix responds sensitively to climate change. In this study, nine larch species and one variety from eleven sites were collected to study the growth characteristics of tree-ring width using dendrochronological methods. Ten residual tree-ring chronologies were developed to analyze their relationships with regional standardized anomaly series by Pearson’s correlation analysis. The results suggest that most of the chronologies had significantly positive correlations with the mean temperature and mean maximum temperature in May. The spring temperature evidently limited the radial growth of the larch species without precipitation control. The largest mean tree-ring width was found in Himalayan Larch in Jilong, whereas Master Larch in Si’er reflected the smallest mean value. Both species presented little climate information in this study. chinese, Potanin, and Tibetan larches are significantly correlated with climate change, implying a huge potential for climate history reconstruction. The elevation of the sampling sites appears to be an important condition for tree-ring growth of larches responding to climate factors.

关键词： Larix Miller tree-ring climate change mean temperature in May

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ON THE OBSERVABILITY AND DETECTABILITY OF LINEAR STOCHASTIC SYSTEMS WITH MARKOV JUMPS AND MULTIPLICATIVE NOISE

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Journal of Systems Science & Complexity 2010年第1期23卷 102-115页

作者： Yuanhua NI Weihai ZHANG Haitao FANG Key Laboratory of Systems and Control Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China. College of information and Electrical Engineering Shandong University of Science and Technology Qingdao China.

This paper presents the notions of exact observability and exact detectability for Markov jump linear stochastic systems of Ito type with multiplieative noise （for short, MJLSS）. Stochastic Popov-Belevith-Hautus （PBH） Criterions for exact observability and exact detectability are respectively obtained. As an application, stochastic H2/H∞ control for such MJLSS is discussed under exact detectability.

关键词： Exact detectability exact observability Markov jump systems multiplicative noise PBH Criterion stochastic H2/H∞ control.

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Continuous wavelet transform and discrete multi-resolution analysis of surface fluxes and atmospheric stability

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Progress in Natural Science:Materials International 2006年第4期16卷 403-409页

作者： JIANG Zhaoyang, YU Qiang, WANG Tianduo, SUN Xiaomin and ZHANG Renhua Shanghai institute of Plant Physiology and Ecology, chinese academy of Sciences, Shanghai 200032, china institute of Geographic Sciences and Natural resources research, chinese academy of Sciences, beijing 100101, china Shanghai institute of Plant Physiology and Ecology Chinese Academy of Sciences Shanghai 200032 China institute of Geographic Sciences and Natural resources research Chinese Academy of Sciences Beijing 100101 China

Variations of land surface fluxes of sensible heat (H), latent heat (LE), and CO2(F-CO2) obtained from the eddy-co-variance measurements above a winter wheat field from March 30 to April 24, 2001 have been studied at scales ranging from 10 minutes to days. Wavelet transform is used in the analysis of land surface fluxes and atmospheric stability (ξ) calculated from the measurements to reveal the changes in land surface fluxes in hours to days scales. The main results are: (1) Concise and compact information about the fluxes, net radiation (Rn), temperature ( T) and ξ in the scale-time domain are extracted from the data by continuous wavelet analysis, and 1 day, 0.5 day and short-period (shorter than 0.5 day) components are revealed. Continuous wavelet coefficients can be used to characterize periodic components of changes in fluxes and ξ. (2) Discrete-time multi-resolution analysis can be used to concentrate total energy variance of time series of the measurements to a small number of coefficients, plotting the relative energy distribution to get several meaningful characteristics of the data. (3) Under neutral atmospheric conditions, the relative energy distributions of the Haar multi-resolution analysis of the three non-dimensional coefficients ( T/T* , q/q * and c/c * ) display clear similarities.

关键词： atmospheric stability flux continuous wavelet transform multi-resolution wavelet analysis.

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A property-based attestation protocol for TCM

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Science china(information Sciences) 2010年第3期53卷 454-464页

作者： FENG DengGuo1,2 & QIN Yu1,2 1State Key Laboratory of information Security, institute of Software, chinese academy of Science, beijing 100190, china 2National Engineering research Center of information Security, beijing 100190, china State Key Laboratory of information Security Institute of Software Chinese Academy of Science Beijing China National Engineering research Center of information Security Beijing China

This paper presents a property attestation protocol for the security chip TCM (trusted cryptographic module) via analyzing the problems of the current property attestation, which is built on the property attestation model with the online trust third party. In the protocol the prover utilizes the zero-knowledge proof by the attribute certificates, configuration commitment and TCM signature, and attests its configuration and status which are compliant with the declarative security property. The protocol is characterized by shorter signature length and lower computations. The security of the protocol is proved at the random oracle model. The protocol can help extend application and improve standard for security chip TCM, and it also has practical value and immediate significance.

关键词： trust computing trust cryptographic module (TCM) property attestation signature of knowl- edge configuration commitment

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Overview of HBV whole genome data in public repositories and the chinese HBV reference sequences

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Progress in Natural Science:Materials International 2008年第1期18卷 13-20页

作者： Guanghua Wu a,b, Huiguo Ding c, Changqing Zeng b,* a Graduate School of chinese academy of Sciences, beijing 100049, china b beijing institute of Genomics, chinese academy of Sciences, beijing 101300, china c beijing Youan Hospital, Capital Medical University, beijing 100069, china Graduate School of chinese academy of Sciences Beijing 100049 China beijing institute of Genomics Chinese Academy of Sciences Beijing 101300 China beijing Youan Hospital Capital Medical University Beijing 100069 China

The number of Hepatitis B virus (HBV) whole genomic sequences in public nucleotide databases (GenBank, EMBL, and DDBJ) had reached 866 by January 1, 2007. Coming from 46 countries and regions, these sequences were categorized as eight genotypes (A–H). With the statistical and phylogenetic analysis on all available complete genomic data of HBV, we here present an overview of HBV sequences in public databases. From all registered 229 HBV genomes in chinese regions as well as 59 sequencing data from our research group, we report the establishment of reference sequences of HBV strains prevailing in china. These analyses provide clues for the effects of HBV genotypes in host clinical progressions, geographic distribution of the infection, and the viral evolutionary history. Moreover, the viral sequence reference would be helpful in the identiffcation of various HBV mutations. Based on the analysis of various public databases, we suggest that the chinese HBV database with the clinical information should be constructed.

关键词： Public databases HBV genomic sequences Genotype Subtype chinese reference sequences

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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 China State Key Laboratory of information Security Institute of Software of Chinese Academy of Science Beijing 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

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