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Formal Verification under Unknown Constraints

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Wuhan University Journal of Natural sciences 2005年第1期10卷 43-46页

作者： LI Guang-hui 1,2.3 , LI Xiao-wei 2.31. School of Information Engineering, Zhejiang Forestry College, Hangzhou 311300, Zhejiang, china 2. institute of computing technology,{2., beijing 100080, china 3. Graduate School of the{2., beijing 100039, china School of Information Engineering Zhejiang Forestry College Hangzhou Zhejiang China institute of computing {2. Chinese Academy of Sciences Beijing China Graduate School of the chinese academy of sciences Beijing China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

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针对小波域量化隐藏方法的图像监测技术研究

通信学报 2004年第7期25卷 71-77页

作者：刘绍辉姚鸿勋高文姜峰哈尔滨工业大学计算机科学与技术学院黑龙江哈尔滨150001

基于对图像小波变化后各子带系数的不同统计特性,提出了一种针对小波域信息隐藏算法的新型图像隐写术分析技术。通过对原始图像和隐藏信息后的图像的小波变换系数子带直方图的分析,得出了小波域信息隐藏对子带系数的改变特性。进一步对... 详细信息

基于对图像小波变化后各子带系数的不同统计特性,提出了一种针对小波域信息隐藏算法的新型图像隐写术分析技术。通过对原始图像和隐藏信息后的图像的小波变换系数子带直方图的分析,得出了小波域信息隐藏对子带系数的改变特性。进一步对系数进行傅立叶变换,从而量化信息隐藏对系数的影响程度。实验结果表明该方法适用于小波域量化隐藏信息算法的检测。

关键词：隐写术分析信息隐藏小波变换傅立叶变换

“5432.略”:国家信息安全保障体系框架研究

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通信学报 2004年第7期25卷 1-9页

作者：王娜方滨兴罗建中刘勇国家发展与改革委员会高技术产业司北京100824 中国科学院计算技术研究所北京100080 国家计算机网络应急技术处理协调中心北京100029

信息安全的问题已经影响到了国家安全,因而需要从战略上研究国家信息安全保障体系的框架。本文从信息安全的表现形式入手,分别给出了信息安全在技术与社会层面上的表现形态,以及与信息安全相关的信息网络的几个基本规律。在此基础上,提... 详细信息

信息安全的问题已经影响到了国家安全,因而需要从战略上研究国家信息安全保障体系的框架。本文从信息安全的表现形式入手,分别给出了信息安全在技术与社会层面上的表现形态,以及与信息安全相关的信息网络的几个基本规律。在此基础上,提出了“5432.国家信息安全战略:从目的、任务、方式、内容的角度,阐述了保障信息与信息系统的机密性、完整性、可用性、真实性、可控性五个信息安全的基本属性;建设面对网络与信息安全的防御能力、发现能力、应急能力、对抗能力四个基本任务;依靠管理、技术、资源等三个基本要素;建设管理体系、技术体系两个信息安全保障的基本体系,最终形成在这一战略指导思想下的国家信息安全保障体系的框架。

关键词：信息安全保障战略

MULTIVARIATE FOURIER SERIES OVER A CLASS OF NON TENSOR-PRODUCT PARTITION DOMAINS

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Journal of Computational Mathematics 2003年第1期21卷 53-62页

作者： Jiachang Sun(Parallel computing Division, institute of Software,{2., beijing 100080, china) Parallel computing Division Institute of Software Chinese Academy of Sciences 北京 100080

This paper finds a way to extend the well-known Fourier methods, to so-called n+1 directions partition domains in n-dimension. In particular, in 2.D and 3-D cases, we study Fourier methods over 3-direction parallel hexagon partitions and 4-direction parallel parallelogram dodecahedron partitions, respectively. It has pointed that, the most concepts and results of Fourier methods on tensor-product case, such as periodicity,orthogonality of Fourier basis system, partial sum of Fourier series and its approximation behavior, can be moved on the new non tensor-product partition case.

关键词： Multivariate Fourier methods Non tensor-product partitions Multivariate Fourier series

Review on the study of entanglement in quantum computation speedup

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chinese Science Bulletin 2007年第16期52卷 2161-2166页

作者： DING ShengChao1,3 & JIN Zhi1,2.1 institute of computing {2.,chinese academy of sciences,beijing 100080,china 2.academy of Mathematics and Systems Science,chinese academy of sciences,beijing 100080,china 3 Graduate University of chinese academy of sciences,beijing 100080,china institute of computing {2. Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China

The role the quantum entanglement plays in quantum computation speedup has been widely disputed. Some believe that quantum computation's speedup over classical computation is impossible if entan-glement is absent,while others claim that the presence of entanglement is not a necessary condition for some quantum algorithms. This paper discusses this problem systematically. Simulating quantum computation with classical resources is analyzed and entanglement in known algorithms is reviewed. It is concluded that the presence of entanglement is a necessary but not sufficient condition in the pure state or pseudo-pure state quantum computation speedup. The case with the mixed state remains open. Further work on quantum computation will benefit from the presented results.

关键词：量子论量子纠缠量子计算加速模拟

FOURIER-LEGENDRE PSEUDOSPECTRAL METHOD FOR THE NAVIER-STOKES EQUATIONS

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Journal of Computational Mathematics 2000年第3期18卷 225-238页

作者： Jian Li (LSEC, institute of Computational Mathematics and Scientific/Engineering computing, {2. of Mathematics and System sciences, chinese academy of sciences, beijing, 100080, china) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京 100080

Constructs a Fourier-Legendre pseudospectral scheme for Navier-Stokes equations with semi-periodic boundary condition. Equation of the scheme; Estimation of errors; Numerical results.

关键词： Navier-Stokes equations Fourier-Legendre pseudospectral method error estimation

SYNTHESIS AND CHARACTERIZATION OF NEW STABILIZERS WITH OPTIMAL MOLECULAR WEIGHT

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chinese Journal of Polymer Science 2001年第4期19卷 341-350页

作者： Jiang-qing Pan institute of Chemistry chinese academy of sciences,{2. china 中科院化学所北京

Over 2.x 10(8) tons of polymers are produced every year, and a large portion of polymers faces the degradation problem. There are many effective methods to protect polymers against degradation and the addition of stabilizers to polymer remains the most convenient and effective way of enhancing polymer life and performance. In this article, a series of effective stabilizers with optimal molecular weight (MW), including common, monomeric and polymeric stabilizers (antioxidant and light stabilizer) were synthesized using isocyanation, controlled isocyanation, hydrosilylation, epoxide addition, macroreaction of stabilizing functional compounds and polymerization of monomeric stabilizers. The structure and performance of these new stabilizers were characterized by using IR, NMR, MS, UV-spectra, XPS and elemental analysis. The current development of stabilizer synthesis was also reviewed.

关键词： preparation of stabilizer antioxidant hindered amine light stabilizer isocyanation hydrosilylation

ON THE CENTRAL RELAXING SCHEMES I:SINGLE CONSERVATION LAWS

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Journal of Computational Mathematics 2000年第3期18卷 313-324页

作者： Hua-zhong Tang (LSEC, institute of Computational Mathematics and Scientific /Engineering computing, {2. of Mathematics and System sciences, chinese academy of sciences, beijing, 100080, china) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京 100080

Presents a central relaxing scheme for scalar conservation laws. Details on the preliminary equations; Properties of the relaxed schemes; Conclusions.

关键词： hyperbolic conservation laws the relaxing scheme TVD cell entropy inequality

THE L^2.NORM ERROR ESTIMATE OF NONCONFORMING FINITE ELEMENT METHOD FOR THE 2.D ORDER ELLIPTIC PROBLEM WITH THE LOWEST REGULARITY

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Journal of Computational Mathematics 2000年第3期18卷 277-282页

作者： Lie-heng Wang (LSEC, institute of Computational Mathematics and Scientific/Engineering computing, {2. of Mathematics and System sciences, chinese academy of sciences, beijing, 100080, china) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京 100080

Presents the abstract L...-norm error estimate of nonconforming finite element method. Use of the Aubin Nitsche Lemma in estimating nonconforming finite element methods; Details on the equations.

关键词： L-2.norm error estimate nonconforming f.e.m. lowest regularity