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Chinese Science Bulletin 2001年第24期46卷 2051-2054页

作者： LIU Zhongyang, XU Demin, GUO Cunyue, WANG Jun, HE Dawei & HU YouliangStale Key Lab of engineering Plastics, Center for Molecular Science, Institute of Chemistry. Chinese Academy of Sciences, beijing 100080, china beijing Lab of Catalysis. china National Petroleum corporation Key Lab of Catalysis, beijing 100080, china State Key Lab of engineering Plastics Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing China beijing Lab of Catalysis China National Petroleum Corporation KeyLab of Catalysis Beijing China

Linear low-density polyethylene (LLDPE) was prepared by in situ polymerization using a dual-functional catalytic system containing Et(Ind)2ZrCl2/MAO and Ti(On-Bu)4./AlEt3 used as co-polymerization catalyst and dimeriza-tion catalyst, respectively. The catalytic system showed high activity and the polymer with low melting point, narrow molecular weight distribution (MWD) and low crystallinity was produced.

关键词： linear low-density polyethylene (LLDPE) in situ poly- merization metallocene.

Neuromorphic Continuous-Time State Space Pole Placement Adaptive Control

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Journal of systems engineering and Electronics 2003年第1期14卷 58-62页

作者： Lu Zhao & Sun MingweiDepartment of Electrical and Computer engineering University of Houston, Houston, U.S. A The Third Academy, china Aerospace Science and Industry corporation, beijing 100074. P. R. china Department of Electrical and Computer engineering University of Houston U. S. A The Third Academy China Aerospace Science and Industry Corporation Beijing 100074 P. R. China

A neuromorphic continuous-time state space pole assignment adaptive controller is proposed, which is particularlyappropriate for controlling a large-scale time-variant state-space model due to the parallely distributed nature ofneurocomputing. In our approach, Hopfield neural network is exploited to identify the parameters of a continuous-timestate-space model, and a dedicated recurrent neural network is designed to compute pole placement feedback control law inreal time. Thus the identification and the control computation are incorporated in the closed-loop, adaptive, real-timecontrol system. The merit of this approach is that the neural networks converge to their solutions very quickly andsimultaneously.

关键词： Pole assignment Parameter identification Hopfield neural network Sylvester's equation Recurrent neural network.

Cognitive Engine Technology

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ZTE Communications 2009年第2期7卷 6-10页

作者： Wang Lifeng, Wei Shengqun (Institute of Chinese Electronic equipment system engineering corporation , {4. 10014. , P . R . china )

Cognitive Radio (CR) is an intelligent radio communication system, whose intelligence mostly comes from the Cognitive Engine (CE). Based on the techniques of software-defined radio and with the support of machine reasoning and learning in artificial intelligence, cognitive engine implements the cognitive loop to realize the abilities of sensing, adaptation and learning in CR. Cognitive engine consists of the modeling system, knowledge base, reasoning engine, learning engine and interfaces. The key techniques are knowledge representation, machine reasoning and machine learning.

关键词： Engine CE Base Radio Cognitive Engine Technology

Integrated Standardization and systems engineering Management

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厦门大学学报（自然科学版） 2002年第S1期41卷 235-236页

作者： RUAN Jin-yuan 1, SUN Shu-tao 2, YU Xin-qi 3, RUAN Xin 4.(1. Ordance Institute of General equipment Department, Shiji azhuang 050000, china 2. Graduate School of Chinese Academic of Science, beijing 10004., china 3. East china University of Science and Technology, Shanghai 200232, china 4. Meterology Bureau of Hebei Province, Shijiazhuang 050021, china)

Integrated standardization is one of the fundamenta l forms of modern standardization. It is the combination of system science and the content of standardization. The development of system science has provided theo retic foundation and precondition for integrated standardization. The relevant r esearch on integrated standardization and system engineering illustrate that int egrated standardization is a advanced method which presented with the developmen t of modern science and technology . Integrated standardization treat the re levant factors of standardization as a system, and wholly standarlize the factor s in order to reach the best level of technology and quality. Integrated standardization is a large system engineering. In modern industr y the contact among different departments is being constantly enlarged and t he complexity of product is being constantly increased. This situation demands s trict correspond and united request in all the following aspects: raw mate rial, organs, fittings, technical measures of production, preparation for produc tion, ways of organizing the production. The traditional measure which establish the respective standard separately must be replaced by multi-spetialty standa rdization in large spectrum. The current situation and the development of syste m science has provided theoretic foundation and precondition for this kind of st andardization. Product or project can be managed with system engineering of proj ect, while the correspond standardization can be managed with system engineering of standardization. Integrated standardization virtually is system engineering of standardization, w hich use the theory to deal with the problem about standardization . This thesis included 3 chapters: 1. the brief summary of integrated standardization and sys tem engineering management in the development of type in foreign countries; 2. t he current situation and existing problems in the development of products; 3. ho w to organize and actualiz

关键词： integrated standardization system engineering ma nagement

Bitstream decoding and SEU-induced failure analysis in SRAM-based FPGAs

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Science china(Information Sciences) 2012年第4期55卷 971-982页

作者： WANG ZhongMing 1,2,YAO ZhiBin 2,GUO HongXia 2 & LV Min 1 1 Department of engineering Physics,Tsinghua University,beijing 100084.china 2 Northwest Institute of Nuclear Technology,Xi'an 710024.china 1. Department of engineering Physics Tsinghua University Beijing 100084 China2. Northwest Institute of Nuclear Technology Xi’an 710024 China

Reconfigurable SRAM-based FPGAs are highly susceptible to radiation induced single-event upsets (SEUs) in space *** bit flip in FPGAs configuration memory may alter user circuit permanently without proper bitstream reparation,which is a completely different phenomenon from upsets in traditional memory *** is important to find the relationship between a programmable resource and corresponding control bit in order to understand the impact of this *** this paper,a method is proposed to decode the bitstream of FPGAs from Xilinx corporation,and then an analysis program is developed to parse the netlist of a specific design to get the configuration state of occupied programmable logic and *** that,an SEU propagation rule is established according to the resource type to identify critical logic nodes and paths,which could destroy the circuit topological *** decoded relationship is stored in a *** database is queried to get the sensitive bits of a specific *** result can be used to represent the vulnerability of the system and predict the on orbit system failure *** analysis tool was validated through fault injection and accelerator irradiation experiment.

关键词： radiation effect single-event effect single-event upset SRAM-based FPGA fault injection

Simulation of Vertical Planetary Mill Based on Virtual Prototyping

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Journal of University of Science and Technology beijing 2001年第2期8卷 86-90页

作者： Ruitao Li, Mei Fang, Wenming Zhang, Yue Ma (Civil and Environmental engineering School, University of Science and Technology beijing, beijing 100083, china) Univ Sci & Technol beijing Civil & Environm Engn Sch Beijing 100083 Peoples R China

The mechanical model of vertical planetary mill is set up, whose dynamic and kinetic characteristics are described as well. Based on the analysis of system dynamics of vertical planetary mill, virtual prototyping technology is applied in the simulation of this mill. The development of virtual prototype of equipment, virtual test and optimization of virtual prototype are stated in detail. Some useful conclusions which have theoretical meaning for the manufacturing of vertical planetary mill have been obtained. Furthermore, it is pointed out that virtual prototyping technology shows great advantage and is bound to become a main method of developing product in the future.

关键词： virtual prototype vertical planetary mill dynamics simulation ADAMS

Design of Lowering the Error Floors of LDPC Codes

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Design of Lowering the Error Floors of LDPC Codes

2005全球移动通信大会

作者： Wang Ruihua Yin Liuguo Yu Quan Communication engineering college PLA Science and technology university. Nanjing 210007 china Department of Electronic engineering Tsinghua University beijing {4. china electronic equipment system engineering corporation beijing 100039 china

＜正＞Aiming at the requirement of very low bit error rate （BER） output in the new generation multimedia transmission system and storage system, a concatenated code construction scheme for low-error-floor low-density parity-check （LDPC） codes is proposed in this paper. The inner code of this scheme is low rate LDPC code that is generated randomly, which is used to correct channel error;the outer code of this scheme is high rate finite geometry LDPC code, which is used to correct residual error. Simulation result shows that this concatenated coding scheme can effectively eliminate the error floor and meet the requirement of the high reliability transmission system.

关键词：

来源： cnki会议评论

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基于闭环形式的车辆减振器热学特性研究

中国公路学报 2012年第4期25卷 153-158页

作者：么鸣涛龙凯贺李平中国航天科工集团公司第四研究院北京100854 北京理工大学机械与车辆学院北京100081 华北电力大学新能源电力系统国家重点实验室北京102206 中国航天科工集团公司北京无线电测量研究所北京100854

为了解决某车辆被动悬架系统中减振器由于温升过高而漏油失效的问题,提出了车辆悬架系统机械特性与其热学特性相互耦合的模型。采用MATLAB/Simulink建立闭环正反馈系统的热-机耦合模型,并通过仿真计算得到某车辆在多种工况以及不同悬架... 详细信息

为了解决某车辆被动悬架系统中减振器由于温升过高而漏油失效的问题,提出了车辆悬架系统机械特性与其热学特性相互耦合的模型。采用MATLAB/Simulink建立闭环正反馈系统的热-机耦合模型,并通过仿真计算得到某车辆在多种工况以及不同悬架参数条件下减振器的温升特性曲线。研究结果表明:随着路面等级的下降、车速的提高、簧上质量的增大以及悬架刚度的减小,减振器的温度升高;车轮刚度对减振器温升特性影响较小;簧下质量对减振器温升特性无影响。

关键词：汽车工程减振器仿真闭环温升

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基于保形迭代深度问题的公钥密码体制

武汉大学学报（理学版） 2008年第5期54卷 552-556页

作者：管海明中国电子设备系统工程公司通信研究所北京100141

提出了一种新的公钥密码体制,其安全性主要在于多变元非线性保形迭代函数A(x)的迭代深度问题,可进行密钥分配、加密和数字签名.第一类A(x)为有限域上的有理分式组,其分子和分母均为线性多项式;第二类A(x)为有限域上的有理分式组,其分子... 详细信息

提出了一种新的公钥密码体制,其安全性主要在于多变元非线性保形迭代函数A(x)的迭代深度问题,可进行密钥分配、加密和数字签名.第一类A(x)为有限域上的有理分式组,其分子和分母均为线性多项式;第二类A(x)为有限域上的有理分式组,其分子或分母有非线性多项式;第三类A(x)为有限环上的非线性多项式组.构造第二、三类A(x)的方法是:先运用二层迭代建立关于系数变量的不定方程组T,再用T的一组特解建立A(x).其独特的编码风格表现为代数意义上的分形(fractal):每个未知元的局部都具有与函数整体相似的结构,而把函数展开、化简后,其函数爆炸方式的规律性就会消失.

关键词：公钥密码体制迭代深度问题保形迭代函数数字签名密钥分配

A new perturbation algorithm and enhancing security of SFLASH signature scheme

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Science china(Information Sciences) 2010年第4期53卷 760-768页

作者： WANG HouZhen1,2, ZHANG HuanGuo1,2*, GUAN HaiMing3 & HAN HaiQing1,2 1The Key Laboratory of Aerospace Information Security and Trusted Computing, Ministry of Education, Wuhan University, Wuhan 4.0072, china 2School of Computer, Wuhan University, Wuhan 4.0079, china 3Chinese Electronic equipment system {4., beijing 100039, china 1. The Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of Education Wuhan University Wuhan 430072 China2. School of Computer Wuhan University Wuhan 430079 China3. Chinese Electronic Equipment System Corporation Beijing 100039 China

This paper introduces the concept of noise factor and noise operation, and constructs a noise group. We present a new perturbation algorithm for enhancing security of multivariate public key cryptosystems (MPKCs). European Consortium SFLASH which derives from Matsumoto-Imai scheme is a fast signature scheme intended for low cost smart cards. It was broken with the differential cryptanalysis by Dubois et al. in 2007. Taking Matsumoto-Imai system as an example, security analysis shows that the new algorithm can powerfully demolish its potential mathematical properties of the public key, and effectively avoid differential cryptanalysis without lowering the effciency of the original algorithm.

关键词： SFLASH differential cryptanalysis noise factor noise operation noise group