一类关于鲁棒性和敏感性的泛函的优化

本文给出了一类泛函的优化方法.这类泛函包括反映系统鲁棒性和敏感性的目标函数. 其优化是通过-Rm×n→Rm×n的映射来实现的.该映射将所有配置系统极点的反馈矩阵参数 化为一自由矩阵变量的函数.     

多变量系统敏感性及鲁棒性综合最优的H∞解耦设计方法

本文利用H∞设计理论提出了一种多变量系统敏感性及鲁棒性综合最优的解耦设计方 法,证明了单变量系统所能达到的最优敏感性及鲁棒性指标值仅由被控对象右半平面的零极 点决定,而与左半平面的零极点无关.另外,本文对谱分解及模型匹配问题的求解算法作了改 进,给出了一个算例.     

Improved migration for mobile computing in distributed networks

A mobile ad hoc network (MANET) is a special type of wireless network in which a collection of mobile nodes with wireless network interfaces may form a temporary network, without the aids of any fixed infrastructure. Security has become a hot research topic in mobile ad hoc networks. In 1998, Volker and Mehrdad proposed a tree-based key management and access control scheme for the mobile agents to manage rights to access its own resources for the visited mobile nodes. Latter, Huang et al. showed that Volker and Mehrdad's scheme needs a large amount of storage and costs for managing and storing secret keys. Huang et al. further proposed a new and efficient scheme based on the elliptic curve cryptosystems to reduce costs and gain better efficiency. However, there is a security leak inherent in Huang et al.'s scheme that the malicious node can overstep his authority to access unauthorized information. This paper will propose a secure, robust, and efficient hierarchical key management scheme for MANETs. Some practical issues and solutions about dynamic key management are also considered and proposed. As compared with Huang et al.'s scheme, our proposed scheme can provide better security assurance, while requiring smaller key-size, lower computational complexities, and constant key management costs which is independent on the number of the confidential files and the visited nodes.     

A standard for developing secure mobile applications

The abundance of mobile software applications (apps) has created a security challenge. These apps are widely available across all platforms for little to no cost and are often created by small companies and less-experienced programmers. The lack of development standards and best practices exposes the mobile device to potential attacks. This article explores not only the practices that should be adopted by developers of all apps, but also those practices the enterprise user should demand of any app that resides on a mobile device that is employed for both business and private uses.     

基于KPCA和SVM的火箭发动机试验台故障诊断方法

为了解决液体火箭发动机试验台的故障诊断问题,提出了一种基于核主元分析(KPCA)特征提取和支持向量多分类机(SVM)的故障诊断方法,该方法首先利用核主元分析对试验台标准故障样本进行特征提取,通过特征分析,建立适合于试验台故障状态识别的层次多分类支持向量机,并对其进行训练,然后将试验数据在主元上投影,输入到训练好的支持向量多分类器,对试验台故障状态进行识别.该方法充分利用了核主元分析强大的非线性特征提取能力和支持向量分类机良好的小样本泛化特性,解决了试验台故障诊断中的小样本、非线性模式识别问题.对试验台的试验结果表明,该方法是有效的、可行的.     

基于xPC目标的实时I／O接口技术研究

使用xPC目标可以将一台PC兼容机制转变为一个实时系统,来实现控制系统的快速原型化、硬件在回路中的测试,与传统方法相比方便、快捷很多。在工程应用中,负责与目标硬件进行实时通信的I／O接口是由I／O板卡及相应的设备驱动程序构成,这也是xPC目标实现的基础。在对比、论述xPC目标所支持的PCI和ISA两种主要总线类型I／O接口技术的基础上,对基于PCI总线的DAQ和多串口设备驱动进行了实际测试。     

A multi-agent system model of a diesel engine using rule induction

The proliferation of a multi-agent system (MAS) and ideas from Artificial Intelligence (AI)/distributed AI have changed the way systems, in general are controlled, and operation of a system (diesel engine) in particular is automated. In this paper a distributed multi-agent architecture for a diesel engine and the knowledge sources that handle electricity generation is developed. Electronic devices and components used for data handling are described. The sensed data are presented in fuzzy logic and calculated in entropy values and depicted in a decision hierarchy. A comparative performance assessment of the proposed multi-agent based system with an existing system is presented and discussed.     

基于人工神经网络和经验知识的遥感信息分类综合方法

提出基于三维Hopfield人工神经网络模型的遥感信息分类综合算法将遥感图象分 类与分类结果平滑过程有机地结合在一起,并方便地引入了经验知识指导网络进化.实验表 明该方法可明显提高森林类型划分、土地利用调查等遥感应用专题的分类精度.     

基于层叠处理的多级自适应WOS滤波器

基于层叠处理的ＬＰ算法求解最优非线性滤波 缺陷在于：⑴必须掌握信号和噪声的先验统计知识,⑵计算量随滤波窗增大呈超指数增加,根据层叠滤波器理论,所有ＷＯＳ滤波器正布尔函数都是线性可分离的,在此基础上,提出了一种多级自适应ＷＯＳ层叠滤波器,从有效地克服了传统ＬＰ算法的缺点,它尤其适合于图象处理领域。