基于MCP25050的CAN总线的网络节点设计

本文给出了一种由MCP250505构成的无需外加CPU的CAN总线节点的设计方案,介绍了CAN总线网络节点的硬件设计和软件设计,并对MCP25050的特性以及相关协议作了详细分析。实验表明,该系统具有结构简单、可靠性高、使用灵活方便、性能价格比高等特点,在分布式数据采集和控制中具有广阔的应用前景。     

远程多通道高精度监测仪编程的抗干扰设计

本文以一台远程多通道高精度的监测仪的软件设计为例，介绍采用C51编程的抗干扰设计思路及方法，为其它精密电子仪器抗干扰设计提供了宝贵经验。     

维与度的对称处理

Codd在提出OLAP概念时强调应该对称处理维与度,但是当今的多数OLAP产品对这一点的支持不够。文章首先给出了一个简单直观的多维数据模型,然后在这个多维数据模型上定义维与度之间的相互转化操作,通过维与度之间的相互转化,“升级”度,“降格”维,把属于维的操作施加给度,把属于度的操作施加给维,从而对称处理维与度。     

作战飞机对雷达的无源对抗及其仿真建模

无源干扰在高科技战争中发挥着重要作用。针对无源干扰物的运动特性及频率特性进行仿真建模 ,并将其用于我军防空兵的模拟训练有着重要意义。该文介绍了几种无源干扰方式 ,并对箔条干扰建模 ,用于一个基于分布交互仿真技术的模拟训练系统。     

网络传输时延的测量方法

介绍了网络传输时延的基本概念，分析了影响网络传输时延的因素，给出了测量传输时延的3种方法，并对各种方法作一综合比较。     

电阻应变计在弯矩测量中的应用

利用金属电阻奕变计式传感器测量弯矩,用三位半液晶显示器显示弯矩值的大小,并依据这一原理,设计出一种新型工具－－数显力矩扳手。     

Evaluation of the effectiveness of features selected by discriminant analysis methods

New theoretical and practical results concerning the use of discriminant analysis for feature selection are presented in the paper. Numerical values for the eigenvalues of the matrix SW_W⁻¹ S_B (within-class and between-class scatter matrices) are investigated. An analytic expression for their minimum value representing the minimum effectiveness is derived. Differences between real values and these minimum values are important for the evaluation of the effectiveness of features and thus for feature selection.     

在线工业镀层及涂层厚度分析仪

产品和金属元件表面镀层或防腐层厚度是与产品质量与性能相关的重要指标。为满足分析要求,介绍了自行研制的同位素X射线荧光分析仪的主要技术方法及具体应用。实际应用效果表明该分析仪在对工业镀层和汽车涂层厚度进行在线测量时其测量精度可达2%～4%,是一种具有快速、简便、无损等优点的新型分析方法。     

地方高校计算机专业应用型人才培养模式探讨*

在分析地方高校计算机科学与技术专业人才培养现状的基础上,提出计算机应用型人才培养新模式,从培养模式、课程体系、教学模式、实践教学、考核形式和师资队伍建设等方面进行探讨,并提出相应的改进措施,为地方高校计算机专业人才培养模式的改革提供几点思路。     

Some results on generalized residual entropy

Shannon’s entropy plays an important role in the context of information theory. Since this entropy is not applicable to a system which has survived for some units of time, the concept of residual entropy has been developed in the literature. Here we generalize the residual entropy by choosing a convex function ? with ?(1) = 0. In this paper, some orderings and aging properties have been defined in terms of the generalized residual entropy function and their properties have been studied. Quite a few results available in the literature have been generalized and some distributions (viz. uniform, exponential, Pareto, power series, finite range) have been characterized through the generalized residual entropy.