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Design and implementation of platform for embedded Ethernet control system

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仪器仪表学报 2008年第6期29卷 1121-1128页

作者： Zhu Lingbo Lin-Shi Xue-Fang dai guanzhong Rétif Jean-Marie College of Automation Northwestern Polytechnical University Xi＇an 710072 China l＇Ecole Doctorale： Electronique Electrotechnique Automatique (EEA) Institute National des Sciences Appliquées de Lyon Villeurbanne 69621 France

A platform named EMECS based on embedded Ethernet control system is implemented.A PC running Fedora 6(Linux2.6)works as a central controller.A kit running Linux 2.4 based on Samsung2410A(ARM920t core)works as a remote controller and a DC motor(ESCA P28HSL18-219/204)made by Portescap Company works as a ***,system modeling is presented by analyzing the characteristics of Ethernet and the plant,based on a proposed delay measurement ***,implementation of the system including program and hardware is described in *** then the delay is measured and the control results of the system are tested in three cases with different network loads as *** platform is proved to have flexibility of running different control algorithms and extensibility of adding *** results demonstrate the validity of the system.

关键词：以太网控制系统设计方案平台

A Fingerprinting Method Based on Module Extraction Used to Protect Intellectual Property

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Wuhan University Journal of Natural Sciences 2006年第6期11卷 1947-1950页

作者： MIAO Sheng dai guanzhong LIU Hang LI Meifeng College of Automation Northwestern Polytechnical University Xi＇an 710072 Shaanxi China

Intellectual Property （IP） reuse methodology has been widely used in Integrate Circuit （IC） design. Meanwhile, the corresponding security problems caused by illegal IP distribution have aroused lots of attentions. Unlike using IP watermark to identify IP＇s ownership, IP fingerprinting can be used to trace illegal distributor. In this paper, IP buyer＇s fingerprint is mapped into different derived instances of extracted modules, and then is embedded into IP to identify distributor in case of illegal distribution. Comparing with other fingerprinting method, the proposed method has some good characteristics such as low design effort, small storage demand, high security and few physical overheads.

关键词： intellectual property watermark fingerprint module extraction

A High-Performance Extraction Method for Public Opinion on Internet

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Wuhan University Journal of Natural Sciences 2007年第5期12卷 902-906页

作者： LI Yanling dai guanzhong ZHU Yehang QIN Sen School of Automatic Control Northwestern Polytechnical University Xi＇an 710072 Shaanxi China Department of Computer and Command Automation The Secondary Artillery Engineering College Xi＇an 710025 Shaanxi China

Aiming at the importance of the analysis for public opinion on Internet, the authors propose a high-performance extraction method for public opinion. In this method, the space model for classification is adopted to describe the relationship between words and categories. The combined feature selection method is used to remove noisy words from the original feature space effectively. Then the category weight of words is calculated by the improved formula combining the frequency of words and distribution of words. Finally, the class weights of the not-categorized documents based on the category weight of words are obtained for realizing opinion extraction. Experiment results show that the method has comparatively high classification and good stability.

关键词： opinion extraction text categorization class spacemodel feature selection

An Efficient ECDSA-Based Signature Scheme for Wireless Networks

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Wuhan University Journal of Natural Sciences 2006年第6期11卷 1707-1710页

作者： XU Zhong dai guanzhong YANG Deming College of Automation Northwestern Polytechnical University Xi＇an 710072 Shaanxi China

Wired equivalent security is difficult to provide in wireless networks due to high dynamics, wireless link vulnerability, and decentralization. The Elliptic Curve Digital Signature Algorithm（ECDSA） has been applied to wireless networks because of its low computational cost and short key size, which reduces the overheads in a wireless environment. This study improves the ECDSA scheme by reducing its time complexity. The significant advantage of the algorithm is that our new scheme needs not to calculate modular inverse operation in the phases of signature generation and signature verification. Such an improvement makes the proposed scheme more efficient and secure.

关键词： signature ECDSA wireless networks

Using Combinational Logic Function to Watermark IP Based on FPGA

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Wuhan University Journal of Natural Sciences 2006年第6期11卷 1679-1682页

作者： MIAO Sheng dai guanzhong MU Dejun LI Meifeng College of Automation Northwestern Polytechnical University Xi＇an 710072 Shaanxi China

In the field of digital circuit design, the extensive applications of reusable intellectual property （IP） simplify the design procedure based on very large scale field programmable gate array （FPGA）, and shorten the time to market （TTM）. However, the flexibility of reusable IP makes itself easy to be stolen and illegally distributed by intruders. The protection method proposed in this paper maps IP owner＇s signature to combinational logic functions, and then implements these functions into unused lookup tables （LUTs） in the design based on FPGA, which can be used as a strong proof of IPs ownership. The related experiment results show that this protection method has favorable characteristics such as low overhead, few effects on performance, and high security.

关键词： field programmable gate array watermark intellectual property

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复杂网络的度分布研究

西北工业大学学报 2006年第4期24卷 405-409页

作者：王林戴冠中西北工业大学自动化学院

复杂网络的度分布与其拓扑结构紧密相关。绝大多数复杂网络具有无标度性（Scalef ree），其幂律度分布完全由度分布指数所确定。文中全面研究了复杂网络的度分布指数与其拓扑结构、形成原因以及传播动力学之间的关系，获得了下列结论：... 详细信息

复杂网络的度分布与其拓扑结构紧密相关。绝大多数复杂网络具有无标度性（Scalef ree），其幂律度分布完全由度分布指数所确定。文中全面研究了复杂网络的度分布指数与其拓扑结构、形成原因以及传播动力学之间的关系，获得了下列结论：实际网络的度分布指数不会低于1；度分布指数介于1～2之间的复杂网络中存在数量较多的HUB节点，其边数与节点数之间的关系是非线性的，节点数的增加将导致边数的大幅度增加；度分布指数介于2～3之间的复杂网络中存在一定数量的HUB节点，其边数与节点数之间的关系是线性的，大多数受成本制约的网络属于这种类型；度分布指数大于3的复杂网络近似于均质网络；度分布指数3构成了复杂网络中病毒防治方式的临界点。

关键词：复杂网络无标度度分布度分布指数

Internet拓扑结构的静态概率模型研究

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西北工业大学学报 2005年第3期23卷 341-346页

作者：王林戴冠中西安理工大学自动化学院陕西西安710048 西北工业大学自动化学院陕西西安710072

近年来,许多学者对Internet的拓扑结构进行了研究,发现了幂律(PowerLaw)规律,然而这些研究基本上针对的是Internet拓扑的局部性质。该文从Internet拓扑的一个参数(度秩指数)出发,定义了Internet拓扑结构的一个静态概率模型。利用静态概... 详细信息

近年来,许多学者对Internet的拓扑结构进行了研究,发现了幂律(PowerLaw)规律,然而这些研究基本上针对的是Internet拓扑的局部性质。该文从Internet拓扑的一个参数(度秩指数)出发,定义了Internet拓扑结构的一个静态概率模型。利用静态概率模型,对文中所提出的Internet拓扑中具有整体意义的两个重要性质(连接率和吸引率)进行了深入研究。通过理论研究和仿真研究,获得了下列成果:①发现了Internet中的一个新的幂律(即连接率满足幂律),并且相关系数超过99.3%。②发现了Internet中吸引率与Internet中幂律之间具有的内在联系;③发现了Internet中的度秩指数的临界值为1。④证明了在Internet中存在自治系统(AS)核心,而对AS核心而言,Internet可视为一个星形结构。

关键词： Internet拓扑结构自治系统(AS)核心幂律静态概率模型

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基于多监测点的蠕虫感染率的自回归估计

西北工业大学学报 2007年第5期25卷 657-661页

作者：邓妍戴冠中西北工业大学自动化学院陕西西安710072

网络的应用给蠕虫提供了传播环境,蠕虫成为网络安全的重要威胁。文中提出了一种基于多监测点的蠕虫感染率的自回归估计方法,该方法侧重时间感染率估计从而为监测预警提供参考信息,确定了基于估计方差的预警门限,给出了预警时刻和监测点... 详细信息

网络的应用给蠕虫提供了传播环境,蠕虫成为网络安全的重要威胁。文中提出了一种基于多监测点的蠕虫感染率的自回归估计方法,该方法侧重时间感染率估计从而为监测预警提供参考信息,确定了基于估计方差的预警门限,给出了预警时刻和监测点数量的关系。仿真试验结果表明,这种方法能有效地对蠕虫感染进行预警。

关键词：蠕虫自回归模型时间感染率

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模糊控制系统的鲁棒稳定性

西北工业大学学报 2001年第2期19卷 296-299页

作者：朱荣明戴冠中西北工业大学陕西西安710072

运用绝对稳定性理论分析常见的单变量二维模糊控制系统的鲁棒稳定性。结果表明 ,模糊控制系统的稳定性与控制量二个分量所处的扇形区域有关 ,且扇形区域越小。

关键词：模糊控制系统绝对稳定性扇形区域鲁棒稳定性