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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

Multi-Step Amplitude Quantization for Ultralow Sidelobe Phased Arrays by Direct Optimization Synthesis

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Journal of Systems Engineering and Electronics 2001年第1期12卷 65-69页

作者： Zhu Huan Wang Yixin Xu Xiaowen & Li Shizhi Dept. of Electronic Engineering, beijing institute of technology, 100081, P. R. china Dept. of Electronic Engineering Beijing Institute of Technology 100081 P. R. China

In this paper, a new amplitude quantization synthesis method for ultralow sidelobe phased arrays is proposed, which is based on the constrained nonlinear optimization algorithm. By introducing a set of critical constraint conditions into the optimization model, we can directly quantize the amplitude distribution instead of replacing it with a continuous equivalent aperture antenna. The mutual coupling and the element patterns are also considered in the quantization synthesis. Finally, some array simulation results are given to show the effectiveness of the method.

关键词： Algorithms computer simulation Directional patterns (antenna) Directive antennas Mathematical models Optimization Vector quantization

A Mobile Agent-Based Prototype of HeterogeneousDistributed Virtual Environment Systems

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Journal of Systems Engineering and Electronics 2000年第2期11卷 61-65页

作者： Ji Qingge(Dept. of computer Science & Engineering, Harbin institute of technology, 150001, P. R. china)Wang Dongmu(beijing Simulation center, 100854, P. R. china)Hong Bingrong(Dept. of computer Science & Engineering, Harbin institute of technology, 150001 Dept. of computer Science&Engineering Harbin Institute of Technology 150001 P. R. China beijing Simulation center 100854 P. R. China

Mobile agents provide a new method for the distributed computation. This paper presents the advantages of using mobile agents in a distributed virtual environment (DVE) system, and describes the architecture of heterogeneous computer's distributed virtual environment system (HCWES) designed to populate some mobile agents as well as stationary agents. Finally, the paper introduces how heterogeneous computer network communication is to be realized.

关键词： Distributed virtual environment Mobile agent Distributed computing

Parallel　Digital　Simulation　for　the　Control　Problem　in　Differential　Algebraic　System

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Journal of Systems Engineering and Electronics 1996年第4期7卷 37-46页

作者： Chen Lirong & Liu Degui(beijing institute of computer Application and Simulation technology,P.O.Box 3929, beijing 100854, P.R.china) beijing institute of computer Application and Simulation technology P.O. Box 3929 Beijing 100854 P.R. China

In this paper, a parallel simulation algorithm for the control problem in differential algebraic system is presented. The error of the algorithm is estimated. The stability analysis is made for a model problem and the... 详细信息

关键词： Parallel simulation algorithm Differential algebraic system Stability analysis.

A New Method for Fractal Dimension Determination by STM at Nanometer Scale

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 64-68页

作者： Qikai Li Yue Zhang Wuyang Chu Chen Wang Chunli Bai (Applied Science School. University of Science and technology beijing, beijing 100083. china)(Chemical institute, Chinese Academy of Science, beijing 100080. china) Applied Science School University of Science and Technology Beijing Beijing 100083 China Chemical institute Chinese Academy of Science Beijing 100080 China

A new method for determining the fractal dimension by STM at nanomeler scale has been ***- Mandelbrot fractal curves were used to verify the accuracy and reliability. The computer simulation showed that fractal dimen- sion obtained with this method generally outran the traditional yard method. The new method has been applied to the fractal dimension determination of the fractures of Ti3Al and Ti-24Al-11Nb alloys. The results show that the fractal dimension of Ti-24Al-11Nb alloy is higher than that of Ti3Al, and it varies with the crark extending orientation.

关键词： fractal dimension STM nanometer scale Ti-Al alloy

DNA computing model based on lab-on-a-chip and its application on solving the timetabling problem

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Progress in Natural Science:Materials International 2008年第5期18卷 633-637页

作者： Fengyue Zhang a,1, Bo Liu b,1, Wenbin Liu c, Qiang Zhang d a Department of Biomedical Engineering, School of Life Science and technology, beijing institute of technology, beijing 100081, china b Chinese Academy of Inspection and Quarantine, beijing 100029, china c College of computer Science and Engineering, Wenzhou University, Wenzhou, Zhejiang 325027, china d Liaoning Key Laboratory of Intelligent Information Processing, Dalian University, Dalian, Liangning 116622, china Department of Biomedical Engineering School of Life Science and Technology Beijing Institute of Technology Beijing 100081 China Chinese Academy of Inspection and Quarantine Beijing 100029 China College of computer Science and Engineering Wenzhou University Wenzhou Zhejiang 325027 China Liaoning Key Laboratory of Intelligent Information Processing Dalian University Dalian Liangning 116622 China

The essential characteristic of DNA computation is its massive parallelism in obtaining and managing information. With the develop- ment of molecular biology technique, the eld of DNA computation has made a great progress. By using an advanced biochip technique, laboratory-on-a-chip, a new DNA computing model is presented in the paper to solve a simple timetabling problem, which is a special ver- sion of the optimization problems. It also plays an important role in education and other industries. With a simulated biological experiment, the result suggested that DNA computation with lab-on-a-chip has the potential to solve a real complex timetabling problem.

关键词： DNA computing Timetabling problem Lab-on-a-chip

Complete quantum circuit of Haar wavelet based MRA

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Chinese Science Bulletin 2005年第16期50卷 1796-1798页

作者： HE Yuguo1,2 & SUN Jigui1,3 1. College of computer Science and technology, Jilin University, Changchun 130012, china 2. Department of computer Science and Engineering, beijing institute of technology, beijing 100081, china 3. Key Laboratory of Computation and Knowledge Engineering of Min-istry of Education, Jilin University, Changchun 130012, china College of computer Science and technology Jilin University Changchun 130012 China

Wavelet analysis has applications in many ar- eas, such as signal analysis and image processing. We pro- pose a method for generating the complete circuit of Haar wavelet based MRA by factoring butterfly matrices and con- ditional perfect shuffle permutation matrices. The factoriza- tion of butterfly matrices is the essential part of the design. As a result, it is the key point to obtain the circuits of I 2t ⊕ W ⊕ I 2n ? 2t ?2. In this paper, we use a simple means to de- velop quantum circuits for this kind of matrices. Similarly, the conditional permutation matrix is implemented entirely, combined with the scheme of Fijany and Williams. The cir- cuits and the ideas adopted in the design are simple and in- telligible.

关键词：量子计算量子算法量子电路 Haar微波 MRA

Prediction-based guidance algorithm for high-lift reentry vehicles

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Science china(Information Sciences) 2011年第3期54卷 498-510页

作者： ZHANG Zhao 1,2 & HU Jun 1 1 beijing institute of Control Engineering, beijing 100190, china 2 Science and technology on Space Intelligent Control Laboratory, beijing 100190, china 1. beijing institute of Control Engineering Beijing 100190 China2. Science and Technology on Space Intelligent Control Laboratory Beijing 100190 China

In this work, we propose a pseudo four-degrees-of-freedom (DOF) prediction based guidance algo- rithm specifically for high-lift reentry vehicles. The algorithm is composed mainly of three parts. First, at the beginning of each guidance cycle, the 4-DOF predictor is called upon to predict the final downrange, crossrange, and heading errors. Then, the magnitude of the bank angle is determined from the downrange error, using the proportional-integral (PI) control method. Finally, two bank angle reversal time points are determined to minimize the crossrange and heading errors. Compared with traditional predictor-corrector guidance, the algorithm proposed does not require iterative procedures which significantly decreases the computational burden for the on-board computer and makes the implementation practical. Simulation results for dispersion tests demonstrated that our algorithm is computationally efficient and robust against uncertainties and disturbances.

关键词： pseudo 4-DOF prediction-based guidance high-lift reentry vehicle

Conformal isoparametric hypersurfaces with two distinct conformal principal curvatures in conformal space

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Science china Mathematics 2010年第4期53卷 953-965页

作者： NIE ChangXiong 1,2,LI TongZhu 3,HE YiJun 4 & WU ChuanXi 5 1 Faculty of Mathematics and computer Sciences,Hubei University,Wuhan 430062,china 2 School of Mathematical Sciences,Peking University,beijing 100871,china 3 Faculty of Sciences,beijing institute of technology,beijing 100081,china 4 School of Mathematical Sciences,Shanxi University,Taiyuan 030006,china 5 institute of Mathematics,Hubei University,Wuhan 430062,china 1. Faculty of Mathematics and computer Sciences Hubei University Wuhan 430062 China2. School of Mathematical Sciences Peking University Beijing 100871 China3. Faculty of Sciences Beijing Institute of Technology Beijing 100081 China4. School of Mathematical Sciences Shanxi University Taiyuan 030006 China5. Institute of Mathematics Hubei University Wuhan 430062 China

The conformal geometry of regular hypersurfaces in the conformal space is *** classify all the conformal isoparametric hypersurfaces with two distinct conformal principal curvatures in the conformal space up to confor... 详细信息

关键词： Lorentz conformal geometry conformal invariants conformal isoparametric hypersurfaces