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Mechanism and Defense on Malicious Code

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 83-88页

作者： WEN Wei-ping 1,2,3, QING Si-han 1,2,31. Institute of Software, the Chinese academy of Sciences, beijing 100080, china 2.Engineering Research Center for Information Security technology, the Chinese academy of Sciences, beijing 100080, china 3.Graduate School of the Chinese academy of Sciences, beijing 100080, china Institute of Software the Chinese Academy of Sciences Beijing 100080 China

With the explosive growth of network applications, the threat of the malicious code against network security becomes increasingly serious. In this paper we explore the mechanism of the malicious code by giving an attack model of the malicious code, and discuss the critical techniques of implementation and prevention against the malicious code. The remaining problems and emerging trends in this area are also addressed in the paper.

关键词： malicious code attacking model mechanism defense system security network security

Some characteristics of the atmosphere during an adiabatic process

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Progress in Natural Science:Materials International 2006年第6期16卷 644-648页

作者： GAO Li, LI Jianping and REN Hongli (LASG, Institute of Atmospheric Physics, Chinese academy of Sciences, beijing 100029, china Graduate School of Chinese academy of Sciences, beijing 100049, china National Climate Center, Laboratory of Climate Studies, china Meteorological Administration, beijing 100081, china) [a]LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China [b]Graduate School of Chinese academy of Sciences Beijing China [c]National Climate Center Laboratory of Climatic Studies China Meterological Administration Beijing China

Some important characteristics of the atmosphere during an adiabatic process are investigated, which include the invariability of atmospheric entropy range and local surface potential temperature, the conservation of the atmospheric mass intervened between any isentropic surface and the ground, and the isentropic surface intersecting with the ground. The analysis shows that the atmospheric reference state (ARS) for investigation on available potential energy (APE) should be defined objectively as the state which could be approached from the existing atmosphere by adiabatic adjustment, and be related to initial atmospheric state before adjustment. For the initial atmosphere state at any time, its corresponding ARS is different from the one at another time. Based on the above-mentioned conclusions, the reference state proposed by Lorenz cannot be obtained physically, so a new conception, the conditional minimum total potential energy, is put forward in order to objectively investigate atmospheric APE.

关键词： available potential energy adiabatic isentropic surface atmospheric reference state conditional minimum total potential energy.

A fiducial argument for generalized p-value

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Science china Mathematics 2007年第7期50卷 957-966页

作者： Xin-min LI~(1+) Xing-zhong XU~2 Guo-ying LI~3 1 Institute of Applied Mathematics,Shandong University of technology,Zibo 255049,china 2 Department of Mathematics,beijing Institute of technology,beijing 100801,china 3 academy of Mathematics and Systems Science,Chinese academy of Sciences,beijing 100800,china Institute of Applied Mathematics Shandong University of Technology Zibo 255049 China Department of Mathematics Beijing Institute of Technology Beijing 100801 China academy of Mathemtics Systems Science Chinese Academy of Sciences Beijing 100800 China

This paper provides a general method for constructing generalized p-value via the fiducial ***,the power properties of the generalized test are *** illustrations, the two-parameter exponential distribution and unbalan... 详细信息

关键词： fiducial distribution generalized p-value frequency property two-parameter exponential distribution variance component 62F03 62E15

Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science china Earth Sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2,3 1. National Marine Environmental Forecasting Center, beijing 100081, china 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese academy of Sciences, beijing 100029, china 3. Graduate University of Chinese academy of Sciences, beijing 100049, china 1. National Marine Environmental Forecasting Center Beijing 100081 China 2. Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. Graduate University of Chinese academy of Sciences Beijing 100049 China

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

Revision of seismic design codes corresponding to building damagesin the “5.12” Wenchuan earthquake

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 147-155页

作者： Wang Yayong Institute of Earthquake Engineering, china academy of Building Research, beijing 100013, china Institute of Earthquake Engineering China Academy of Building Research Beijing 100013 China

A large number of buildings were seriously damaged or collapsed in the "5.12" Wenchuan earthquake. Based on field surveys and studies of damage to different types of buildings, seismic design codes have been updated. This paper briefly summarizes some of the major revisions that have been incorporated into the "Standard for classification of seismic protection of building constructions GB50223-2008" and "Code for Seismic Design of Buildings GB50011-2001." The definition of seismic fortification class for buildings has been revisited, and as a result, the seismic classifications for schools, hospitals and other buildings that hold large populations such as evacuation shelters and information centers have been upgraded in the GB50223-2008 Code. The main aspects of the revised GB50011-2001 code include: (a) modification of the seismic intensity specified for the Provinces of Sichuan, Shanxi and Gansu; (b) basic conceptual design for retaining walls and building foundations in mountainous areas; (c) regularity of building configuration; (d) integration of masonry structures and precast RC floors; (e) requirements for calculating and detailing stair shafts; and (f) limiting the use of single-bay RC frame structures. Some significant examples of damage in the epicenter areas are provided as a reference in the discussion on the consequences of collapse, the importance of duplicate structural systems, and the integration of RC and masonry structures.

关键词： Wenchuan earthquake earthquake damage to buildings revision of seismic design codes

Formal analysis and design of multi-party fair exchange protocols

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Science in china(Series F) 2006年第2期49卷 155-174页

作者： QING Sihan1,2,3 & LI Gaicheng1,3 1. Engineering Research Center for Information Security technology, Institute of Software, Chinese academy of Sciences, beijing 100080, china 2. beijing Zhongke Ansheng Corporation of Information technology, beijing 100080, china 3. Graduate School of the Chinese academy of Sciences, beijing 100039, china 1. Engineering Research Center for Information Security technology Institute of Software Chinese Academy of Sciences Beijing 100080 China 2. beijing Zhongke Ansheng Corporation of Information technology Beijing 100080 China 3. Graduate School of the Chinese academy of Sciences Beijing 100039 China

Based on the origin of message items and channel combination between transacting parties, and events and relations among events, this paper presents a concise, precise, and hierarchical model for general fair exchange protocols, formally specifies various security requirements which are able to reflect inherent requirements for fair exchange protocols more rigorously, and partition these security requirements with fine granularity. This work helps analyze, debug, and design multi-party fair exchange protocols more effectively and elaborately,

关键词： fair exchange logical protocol formal model security requirement.

Semi-analytical analysis of the response of the air temperature over the land surface to the global vegetation distribution

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Chinese Science Bulletin 2009年第14期54卷 2499-2505页

作者： LIU Fei1,2 & CHAO JiPing3,4 1 Institute of Atmospheric Physics, Chinese academy of Sciences, beijing 100029, china 2 Graduate University of Chinese academy of Sciences, beijing 100049, china 3 National Marine Environmental Forecasting Center, beijing 100081, china 4 First Institute of Oceanography, State Oceanic Administration of china, Qingdao 266061, china Institute of Atmospheric Physics Chinese academy of Sciences Beijing 100029 China Graduate University of Chinese academy of Sciences Beijing 100049 China National Marine Environmental Forecasting Center Beijing 100081 China First Institute of Oceanography State Oceanic Administration of China Qingdao 266061 China

Response of the air temperature over the land surface to the global vegetation distribution is investigated, using a three-dimensional governing equation to simulate the steady, large-scale, limited amplitude perturbation of the free, inviscid and adiabatic atmosphere. The adoption of the static equation leads to a temperature governing equation in the terrain following coordinate. With the prescribed temperature as the upper boundary condition and the radiation balance as the lower boundary condition, the semi-analytical solution of the global circulation temperature can be calculated. In this article, only the air temperature (at 2 m height) over the land surface is analyzed, and the result suggests that this model can simulate the air temperature pattern over the land surface reasonably. A better simulation occurs when a simple feedback of the albedo on the temperature is included. Two sensitivity experiments are analyzed through this model. One suggests that the air temperature over the land surface descends obviously when the land surface is covered with ice all over, while another suggests that the air temperature rises a little when the land surface is covered with forest except the ice-covered area. This model appears to be a good tool to study the response of the air temperature to the vegetation distribution. Limitations of the model are also discussed.

关键词：空气温度植被分布陆地表面反应解析分析模拟模式控制方程边界条件

Comparison of dynamic changes in endogenous hormones and sugars between abnormal and normal Castanea mollissima

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Progress in Natural Science:Materials International 2008年第6期18卷 685-690页

作者： Tao Liua,b,Yunqian Hua,*,Xiaoxian Li a aKunming Institute of Botany,Chinese academy of Sciences,Kunming 650204,china bGraduate University of the Chinese academy of Sciences,beijing 100049,china Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China Graduate University of the Chinese academy of Sciences Beijing 100049 China

To elucidate the possible functions of endogenous hormones in the flowering of chestnut,concentrations of four endogenous hor-mones[indole-3-acetic acid(IAA),gibberellic acid(GA),abscisic acid(ABA),zeatin riboside(ZR))and the soluble sugars content were measured in both normal and developmentally abnormal Chinese chestnut(Castanea mollissima)during flowering and fruiting *** results showed that the contents of ZR,ABA,and GA exhibited a significant dierent pattern in normal trees from that in abnormal trees,while the contents of IAA and soluble sugars showed a similar change pattern between *** results suggest that quantitative changes in endogenous hormones may correspond to dierent flowering and fruiting mechanisms.

关键词： Castanea mollissima Endogenous hormones Soluble sugars

Effect of upward ion on field-aligned currents in the near-earth magnetotail

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Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 673-680页

作者： ZHANG LingQian1, LIU ZhenXing1, MA ZhiWei2, SHEN Chao1, ZHOU XuZhi3 & ZHANG XianGuo3 1 Center for space and Applied Research, Chinese academy of Sciences, beijing 100080, china 2 Institute of Plasma Physics, Chinese academy of Sciences, Hefei 230031, china 3 School of Earth and space Science, Peking University, beijing 100871, china 1. Center for space and Applied Research Chinese Academy of Sciences Beijing 100080 China 2. Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 China 3. School of Earth and space Science Peking University Beijing 100871 China

A 3-dimensional resistive MHD simulation was carried out to study the effect of the upward ions on the field-aligned currents (FACs) in the near-earth magnetotail. The simulation results show that the up-flow ions originating from the nightside auroral oval would drift into the center plasma sheet along the magnetic field lines in the plasma sheet boundary, and have an important effect on the field-aligned currents. The main conclusions include that: 1) the upward-ions mainly affect the field- aligned currents in the near-earth magnetotail (inside 15 Re); 2) the generated FACs in the near-earth region have two types, i.e., Region 1 FAC in the high-latitude and Region 2 FAC in the low-latitude; 3) FACs increase with the enhancement of the upward ion flux; 4) with the same flux of the upward ions, FACs enhance with the increase of the velocity of the up-flow ions; 5) the intensification of FACs is also closely related with the latitude of the upward ions, and the ions from the closed field line region generate larger FACs; 6) the generation of FACs is closely related with By created by the upward ions.

关键词： up-flow ions, near-earth magnetotail, field-aligned current