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A novel logic-based automatic approach to constructing compliant security policies

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Science china(Information sciences) 2012年第1期55卷 149-164页

作者： BAO YiBao1,2,4,YIN LiHua1,FANG BinXing 1,3&GUO Li 1 1Institute of Computing Technology,chinese academy of sciences,beijing 100190,china 2Institute of Electronic Technology,Information Engineering university,Zhengzhou 450004,china 3beijing university of Posts and Telecommunications,beijing 100190,china 4graduate university,the chinese academy of Science,beijing 100049,china Institute of Computing Technology Chinese Academy of Sciences Institute of Electronic Technology Information Engineering University beijing university of Posts and Telecommunications graduate university the Chinese Academy of Science

It is significant to automatically detect and resolve the incompliance in security *** existing works in this field focus on compliance verification,and few of them provide approaches to automatically correct the incompliant security *** paper proposes a novel approach to automatically transform a given security policy into a compliant *** security policy Π and delegation policy M declared by logic programs,the approach automatically rewrites Π into a new one ΠM which is compliant with M and is readable by the *** prove that the algorithm is sound and complete under noninterference ***,we show that the security policy query evaluation algorithm with conflict and unsettlement resolution still works very well on Π*** approach is automatic,so it doesn't require a administrator with excess *** this sense,our proposal can help us to save much manpower resource in security management and improves the security assurance abilities.

关键词： security policy rewriting logic program compliance

The roles of a decision support system in applying forest ecosystem management in Northeast china

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Science china(Technological sciences) 2006年第z1期49卷 9-18页

作者： DAI Limin, ZHENG Bofu, Guofan Shao & ZHOU Li State Key Lab of Systems Ecology, Research Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china Institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, china Department of Forestry and Natural Resources, Purdue university, West Lafayette, IN 47907, USA graduate university of chinese academy of sciences, beijing 100101, china State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Institute of Applied Ecology Chinese Academy of Sciences Department of Forestry and Natural Resources Purdue University

Forest ecosystems provide a variety of services and forest ecosystem management (FEM) is an effective approach to maximize the services. Because of the complexity of forest ecosystems, the applications of FEM can be facilitated with decision support systems (DSS) that recognize and incorporate ecological and socio-economic variables. With the rapid development of computation and information technologies, DSS have been advanced in many ways. Traditional forest management within a forestry unit in china is planned on a yearly basis. The planning itself remains primarily a verbal concept as there are no quantitative decision-support tools available to translate the concept into forest management actions. For the purposes of FEM at the management level, a forest management DFF, FORESTAR, has been developed under a framework of geographic information system (GIS) and forest models. The paper explained the intelligent modeling mechanisms and demonstrated how the applications of FEM can be strengthened with the applications of FORESTAR.

关键词： forest functions, forested landscapes, forest services, forest models, geographic information systems.

Evidence of a two-component jet in the afterglow of GRB 070419A

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 265-266页

作者： ZHENG WeiKang1,2 & DENG JinSong1 1 National Astronomical Observatories,chinese academy of sciences,beijing 100012,china 2 graduate university of chinese academy of Science,beijing 100049,china National Astronomical Observatories Chinese Academy of Sciences Beijing China graduate university of chinese academy of Science Beijing China

A two-component jet model is proposed to explain the unusual afterglow of GRB *** the optical light curve,a wide "jet" with an opening angle of >30-40 degrees is assumed to produce the late shallow decay,while the three early power-law segments must be caused by a narrow jet with an opening angle of-2-4 *** energy injections to both components are *** X-ray emission may come from either the wide jet or the narrow *** the latter is correct,the jets may run into an ISM environment and the temporal index of the late energy injection may be q-0.65.

关键词： gamma-rays:bursts gamma-rays:observations

cDNA cloning, expression and antibacterial activity of lysozyme C in the blue shrimp (Litopenaeus stylirostris)

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Progress in Natural Science:Materials International 2009年第7期19卷 837-844页

作者： Weijun Mai a,b, Chaoqun Hu a, a Applied Marine Biology Laboratory, South china Sea Institute of Oceanology, Science academy of china, Guangzhou 510301, china b graduate university of chinese academy of sciences, beijing 100049, china Applied Marine Biology Laboratory South China Sea Institute of Oceanology Science Academy of China Guangzhou 510301 China graduate university of chinese academy of sciences Beijing 100049 China

The gene coding for lysozyme in blue shrimp (Litopenaeus stylirostris) was cloned, sequenced and expressed in pET-32a vector. The deduced amino acid sequence of F. merguiensi lysozyme showed 37–93% similarity with the mouse, human, chicken, and tiger prawn counterparts. The lysozyme was purified to homogeneity and observed as a band of approximately 15 kDa in 15% SDS–PAGE. Semiquantitative RT-PCR analysis demonstrated that mRNA transcripts of lysozyme could be mainly detected in the tissues of haemocytes, gill, gonad and the lymphoid organ of unchallenged shrimps, whereas the expression of lysozyme transcripts was increased in all the tested tissues after the heat-killed Vibrio alginolyticus challenge. The temporal expression of lysozyme mRNA in haemolymph challenged by Micrococcus luteus and V. alginolyticus was both up-regulated and reached the maximum level at 8 and 16 h post-stimulation, respectively, and then dropped back to the original level. Bacteriolytic activity of the lysozyme against different bacterial cultures was determined by the solid phase and turbidimetric assays. The results demonstrated that the lysozyme we obtained was not only against Grampositive and Gram-negative bacteria but also against shrimp pathogens V. alginolyticus and V. parahemolyticus. In addition, the study of the inhibition mechanism revealed that the antibacterial activity of the lysozyme was a result of the bactericidal effect.

关键词： Lysozyme C Litopenaeus stylirostris PCR-cloning Expression Antibacterial activity

Relationship between Surface Pollen and Modern Vegetation in Southwestern china

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Journal of Mountain Science 2010年第2期7卷 176-186页

作者： PAN Tao DAI Erfu and WU Shaohong Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China graduate university of chinese academy of sciences BeO'ing 100049 China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

Based on the pollen data obtained from thirty-five surface soil samples and investigated vegetation data from seven plant quadrats,the quantitative relationship between surface soil pollen and modern vegetation are studied in the longitudinal range-gorge region (LRGR) in Southwestern china.R-values (referring to pollen assemblages) are calculated with pollen percentage and plant *** coefficients of similarity between pollen and vegetation are *** results show that the pollen assemblages on surface soil of all vegetation zones can basically represent the native vegetation,but the pollen assemblages are not fully according with the *** is due to the influencing factors including pollen preservation ability,pollen production,amount of exotic pollen and pollen *** pollen representation in surface soil is different in families and *** pollen of woody plants such as Pinus,Tsuga,Alnus,Fagus and Castanopsis are over-representative,but those of Quercus,Carpinus Myrica,Elaeocarpaceae,Ericaceae,Theaceae and Llex are underrepresentative;the pollen of herbaceous plants such as Artemisia and Rubiaceae are over-representative,while those of others including Gramineae and Araliaceae are *** R-values of the same taxon pollen in different vegetation zones are different,depending on their distances from the pollen *** coefficients of the similarity between plant communities and pollen assemblages are mostly over 70%,which indicate again that the surface soil pollen and spores assemblages can represent the *** is concluded that there is a good corresponding relationship between surface pollen assemblages and native vegetation in LRGR,and it is of great significance for reconstructing the past vegetation and paleoclimate using quantitative fossil pollen data in this region.

关键词： Longitudinal range-gorge region (LRGR) Pollen assemblage Vegetation R-value Coefficient of similarity

RADIAL BASIS FUNCTION INTERPOLATION IN SOBOLEV SPACES AND ITS APPLICATIONS

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Journal of Computational Mathematics 2007年第2期25卷 201-210页

作者： Manping Zhang (School of Mathematical sciences,Fudan university,Shanghai 200433,china Institute of Computational Mathematics,chinese academy of sciences,beijing 100080,china School of Mathematical sciences Fudan University Shanghai 200433 China Institute of Computational Mathematics Chinese Academy of Sciences Beijing 100080 China

In this paper we study the method of interpolation by radial basis functions and give some error estimates in Sobolev space H^k（Ω）（k 〉 1）. With a special kind of radial basis function, we construct a basis in H^k（Ω） and derive a meshless method for solving elliptic partial differential equations. We also propose a method for computing the global data density.

关键词： Sobolev space Radial basis function Global data density Meshless method

Joint source channel VL coding/decoding for deep space communication networks based on a space trellis

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Science china(Information sciences) 2011年第9期54卷 1883-1894页

作者： WU WeiRen 1,TU Juan 2,TU GuoFang 1,GAO ShaoShuai 1 & ZHANG Can 1,3 1 School of Information Science and Engineering,graduate university of chinese academy of sciences,beijing 100049,china 2 beijing Institute of Electronic System Engineering,china Aerospace Science & Industry Corp.,beijing 100854,china 3 State Key Laboratory of Information Security,graduate university of chinese academy of Science,beijing 100049,china School of Information Science and Engineering Graduate University of Chinese Academy of Sciences beijing Institute of Electronic System Engineering China Aerospace Science & Industry Corp

This paper presents joint source channel variable length (VL) coding/decoding based on a space *** constructing a joint decoding plane trellis,better decoding performance can be achieved than by using the bit-level decoding ***,the plane trellis is complicated,which results in high decoding complexity for decoding VL turbo *** solve this problem,we construct a space trellis and design a low-complexity joint decoding algorithm with a variable length symbol-a posteriori probability (VLS-APP) algorithm in resource constrained deep space communication *** results show that the proposed approach reduces the decoding complexity by 10% compared with the plane trellis,and the gain of Eb/N0 is about 0.2 dB at SER=***,it provides substantial error protection for variable-length encoded image data.

关键词： joint coding/decoding VL turbo codes space trellis VLS-APP

Nitrogen isotopic composition of plant-soil in the Loess Plateau and its responding to environmental change

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chinese Science Bulletin 2009年第2期54卷 272-279页

作者： LIU WeiGuo1,2 & WANG Zheng1,3 1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, chinese academy of sciences, Xi’an 710075, china 2 Xi’an Jiaotong university, School of Human Settlement and Civil Engineering, Xi’an 710049, china 3 graduate university of chinese academy of sciences, beijing 100049, china chinese Acad Sci Inst Earth Environm State Key Lab Loess and Quaternary Geol Xian 710075 Peoples R China.

The nitrogen isotope of soil is of emerging significance as an indicator of climatic change and biogeochemical cycle of nitrogen in nature systems. In this paper, the nitrogen content and isotopic composition of modern ecosystems from arid and semiarid Loess Plateau in northwestern china, including plant roots and surface soil, were determined to investigate trends in δ15N variation of plant roots and soil along a precipitation and temperature gradient in northwestern china under the East Asian Monsoon climate condition. The δ15N values of surface soil from the study area vary from ?1.2‰ to 5.8‰, but from -5.1‰ to 1.9‰ in the plant roots. Our results indicate that (1) although the isotopic compositions of both plant roots and surface soil change with a similar trend along the climate gradient, the apparent nitrogen difference between plant roots and soil existed, with -δ15N values ranging from 0.3‰ to 7.2‰ with average of 4.1‰; and (2) mean annual precipitation (MAP) is the dominant factor for isotopic composition of plant-soil nitrogen in the Loess Plateau, and the δ15N values are less correlated with MAT; we suggest that nitrogen isotopic composition of soil is a potential tracer for environmental changes.

关键词：氮同位素物理性质化学性质环境论

A mixed method for measuring low-frequency acoustic properties of macromolecular materials

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 729-739页

作者： LIU Hongwei1,YAO Lei1,3,ZHAO Hong1,3,ZHANG Jichuan2,3 & XUE Zhaohong2 1. National Key Laboratory of Acoustics,Institute of Acoustics,chinese academy of sciences,beijing 100080,china 2. Institute of Chemistry,chinese academy of sciences,beijing 100080,china 3. graduate university of chinese academy of sciences,beijing 100049,china National Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China Institute of Chemistry Chinese Academy of Sciences Beijing China

A mixed method for measuring low-frequency acoustic properties of macro-molecular materials is presented. The dynamic mechanical parameters of materials are first measured by using Dynamic Mechanical Thermal Apparatus(DMTA) at low frequen-cies,usually less than 100 Hz; then based on the Principles of Time-Temperature Super-position (TTS),these parameters are extended to the frequency range that acousticians are concerned about,usually from hundreds to thousands of hertz; finally the extended dynamic mechanical parameters are transformed into acoustic parameters with the help of acoustic measurement and inverse analysis. To test the feasibility and accuracy,we measure a kind of rubber sample in DMTA and acquire the basic acoustic parameters of the sample by using this method. While applying the basic parameters to calculating characteristics of the sample in acoustic pipe,a reasonable agreement of sound absorp-tion coefficients is obtained between the calculations and measurements in the acoustic pipe.

关键词： low-frequency acoustic properties,dynamic mechanical properties,Principles of Time-Temperature Superposition,acoustic pipe,sound absorption coefficient.