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一种不定长特征模式入侵检测模型及仿真分析

系统仿真学报 2008年第22期20卷 6118-6121页

作者：葛方斌杨林王建新臧垒解放军理工大学指挥自动化学院江苏南京210007 中国电子系统工程研究所北京100039

针对定长序列模式在刻画序列特征方面的不足,提出了一种不定长序列特征模式抽取算法,并以此为基础设计了一个新的入侵检测模型。模型引入了状态转移概念并将模式匹配检测和状态转移检测结合在一起,克服了已有模型只专注于单一特征检测... 详细信息

针对定长序列模式在刻画序列特征方面的不足,提出了一种不定长序列特征模式抽取算法,并以此为基础设计了一个新的入侵检测模型。模型引入了状态转移概念并将模式匹配检测和状态转移检测结合在一起,克服了已有模型只专注于单一特征检测的缺陷。实验证实,和单特征检测相比,该模型在保证检测率的同时降低了误报率,并且检测算法的效率也是可接受的。

关键词：入侵检测系统调用特征模式状态转移

Fractional Fourier domain equalization for single carrier broadband wireless systems

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Science china(Information Sciences) 2012年第10期55卷 2257-2268页

作者： HUANG KeWu 1,2,TAO Ran 1 & WANG Yue 1 1 Department of electronic engineering,beijing institute of Technology,beijing 100081,china 2 institute of Manned Space system engineering,china Academy of Space Technology,beijing 100094,china Department of electronic engineering Beijing Institute of Technology Beijing China institute of Manned Space system engineering China Academy of Space Technology Beijing China

In this paper,a novel single carrier equalization approach in the fractional Fourier domain(FRFD) is *** can remove all the inter-symbol interference(ISI) and avoid the considerable noise enhancement of the frequency domain-zero forcing(FD-ZF) *** the fractional Fourier transform makes a chirp spread,the impulse response of the deep fading channel may be flattened in some orders of the FRFD while it would be greatly attenuated in the *** searching for an optimal order under certain criterion,we take advantages of the ZF algorithm to mitigate the effects of the ISI *** approach can overcome the contradiction between the ISI mitigation and the noise enhancement of the FD-ZF *** analysis and simulation results show that the proposed FRFD-ZF equalizer can achieve a significant performance and have the same computation cost O(N log N) as the conventional FD linear equalizer,especially in the frequencyselective deep-fading channels.

关键词： fractional Fourier transform single carrier systems zero-forcing equalizer frequency domain linear equalizer

Application of asymptotic waveform approximation technique to hybrid FE/BI method for 3D scattering

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Science in china(Series F) 2007年第1期50卷 124-134页

作者： PENG Zhen1,2,3 & SHENG XinQing2 1 institute of electronics, Chinese Academy of Sciences, beijing 100080, china 2 Department of electronic engineering, beijing institute of Technology, beijing 100081, china 3 Graduated University of Chinese Academy of Sciences, beijing 100039, china institute of electronics Chinese Academy of Sciences Beijing China Department of electronic engineering Beijing Institute of Technology Beijing China Graduated University of Chinese Academy of Sciences Beijing China

The asymptotic waveform evaluation （AWE） technique is a rational function approximation method in computational mathemetics, which is used in many appllcations in computational electromagnetlca. In this paper, the performance of the AWE technique in conjunction with hybrid finite element/boundary integral （FE/BI） method is firstly Inveetlgeted. The formuletlon of the AWE applied in hybrid FE/BI method is given in detail. The characteristic implementation of the application of the AWE to the hybrid FE/BI method is discussed. Numarlcel results demonstrate that the AWE technique can greatly speed up the hybrid FE/BI method to acquire wide-band and wide-angle backecatter radar-cross-section （RCS） by complex targets.

关键词： hybrid FE/BI AWE electromagnetic scattering RCS

engineering system Theory─A New engineering Meta-Discipline

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Journal of systems engineering and electronics 1999年第1期10卷 1-3页

作者： Wang Liancheng(beijing institute of electronic system engineering, 100854, P. R. china)(Received July 2, 1998) beijing institute of electronic system engineering 100854 P. R. China

This paper proposes a new engineering disciplin─engineering system Theory. It dis cusses rendered background, research objects and contents of the engineering system theory briefly. Finally, the met-discipline standing of the engineering system theory in the whole knowledge system of engineering science and its development potential are pointed out.

关键词： engineering system Discipline systems theory.

On the TOPS mode spaceborne SAR

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Science china(Information Sciences) 2010年第2期53卷 367-378页

作者： BAI Xia 1 , SUN JinPing 2 , HONG Wen 3 & MAO ShiYi 2 1 Department of electronic engineering, beijing institute of Technology, beijing 100081, china 2 Department of electronic engineering, Beihang University , beijing 100191, china 3 institute of electronics,Chinese Academy of Sciences, beijing 100190, china Department of electronic engineering Beijing Institute of Technology Beijing China Department of electronic engineering Beihang University Beijing China institute of electronics Chinese Academy of Sciences Beijing China

TOPS (terrain observation by progressive scans) is a recently proposed SAR mode for wide swath acquisition, which aims at achieving the same coverage and resolution as the SCAN mode besides creating scalloping-free images. In this paper, a general SAR imaging model used in TOPS and other SAR modes is introduced, where the antenna sweep rate, Doppler centroid rate, illumination time and azimuth resolution are described by a parameter defined as the "mode factor". After analyzing the characteristics of TOPS signal, an algorithm based on chirp-z transform is proposed, in which a new de-rotation function is used. Simulation results validate the proposed algorithm.

关键词： synthetic aperture radar acquisition mode TOPS

Reconfigurable design and implementation of the MD6 Hash function

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The Journal of china Universities of Posts and Telecommunications 2010年第2期17卷 109-115页

作者： GAO Xian-wei Department of electronic and Information engineering,beijing electronic Science and Technology institute,beijing 100070,china Department of electronic and Information engineering Beijing Electronic Science and Technology Institute Beijing 100070 China

Efficient reconfigurable field programmable gate array （FPGA） architectures for the MD6-224/256/384/512 Hash algorithm are proposed in this article. The basic iterative compact design requires 923 ALMs and achieves a throughput ranging from 225 Mbit/s to 394 Mbit/s at a maximum frequency of 198 MHz. The 32-step-urtrolled high-throughput design requires 7 090 ALMs and achieves a throughput ranges from 5 776 Mbit/s to 9 490 Mbit/s at a maximum frequency of 173 MHz. The simulation results show that high flexibility and efficient FPGA implementation of the MD6 Hash function is achieved.

关键词： SHA-3 MD6 reconfigurable iterative loop-unrolling

Automatic generalization of metro maps based on dynamic segmentation

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Science china(Technological Sciences) 2010年第S1期53卷 158-165页

作者： DONG WeiHua 1,TIAN Yuan 2 & ZHANG Yi 2 1 institute of Geography and Remote Sensing,beijing Normal University,beijing 100875,china 2 institute of Remote Sensing and Geographic Information system,Peking University,beijing 100871,china institute of Geography and Remote Sensing Beijing Normal University Beijing China institute of Remote Sensing and Geographic Information system Peking University Beijing China

A metro map is usually optimized for the readability of connections and transportation networks *** order to assure good readability and meet aesthetic considerations,a set of principles for good metro map layout are *** to these principles,a new methodology based on dynamic segmentation is presented to produce the metro maps ***,routes are constructed according to the line attribute similarity and geometry *** a set of cartographic generalization methods about the shape,angle,length,and topology are presented for these *** method is validated by beijing metro plan *** the experiment results,it can be concluded that this new method is more effective than the static segmentation method to produce metro maps with better readability for route plans.

关键词： metro maps generalization dynamic segmentation visualization

Model-based approach for available bandwidth prediction in multi-hop wireless networks

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Science china(Information Sciences) 2011年第9期54卷 1916-1927页

作者： ZHAO HaiTao 1,WANG Shan 1,WEI JiBo 1,SONG An 1 & LI Ying 2 1 College of electronic Science and engineering,National University of Defense Technology,Changsha 410073,china 2 china electronic system engineering Company,beijing 100141,china College of electronic Science and engineering National University of Defense Technology Changsha China china electronic system engineering Company Beijing China

We present a complete and practical analytical model for the IEEE 802.11-based multi-hop wireless *** features of our model are that it first takes into account the realistic problems both from the physical and MAC (Media Access Control) layers in multi-hop wireless networks,including packet collisions,neighboring interference,hidden node problems,capture effects,non-ideal channels,non-saturated situations and multi-rate sending scenarios,which makes the analytical results more ***,it relates the network parameters to the bandwidth requirements of flows and thus is capable of directly analyzing bandwidth-sensitive ***,it provides a 'what-if' analysis,enabling us to predict the performance of the network after a new flow *** on this model,we then present and validate iterative algorithms for end-to-end available bandwidth *** the property of fast convergence and easy realization,these algorithms can give predictive estimates on the change of parameters that will affect the available bandwidth and thus enable us to obtain more accurate available bandwidth information.

关键词： available bandwidth quality of service multi-hop wireless networks IEEE 802.11 network modeling

CONVERGENCE OF VORTEX METHODS FOR 3-D EULER EQUATIONS

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Journal of Computational Mathematics 2000年第3期18卷 239-250页

作者： Jia-fu Lin (institute of system Science, Academy of Mathematics and system Sciences, Chinese Academy of Sciences, beijing, 100080, china School of Mathematical Sciences, Peking University, beijing 100871, china) 中科院系统科学所北京 100080

Presents a study on the convergence of vortex methods for the three-dimensional Euler equations in bounded domains. Related studies on the convergence of vortex methods; Formulation of vortex methods; Convergence for ... 详细信息

关键词： Euler equations vortex methods convergence initial-boundary value problem