基于嵌入式的远程图像采集传输系统的研究

本文就嵌入式系统的一些相关技术,以及一些网络技术的发展结合起来,介绍嵌入式系统的一些模块的程序设计,通过实质性的一些技术研究,来实现远程图像的采集以及传输。在传输过程中,为了提高系统的稳定性,对嵌入式系统中的图像传送提出了一些新的要求,实现了嵌入式系统的优化。     

浅论计算机网络与通信系统的融合

该文针对当前计算机网络与通信系统之间存在的一些含混概念和问题,从系统观点分析了通信系统与计算机网络系统的功能分工和界定;然后从信息技术综合发展观点分析了通信系统与计算机网络系统进一步融合的趋势。并在其中提出了一些对计算机网络系统和通信系统融合的一些意见和看法。     

过程自动化系统

过程控制系统包含不同的特性和功能,尽管其中的一些尚未被开发使用,但有一些则促使了系统的升级,扩大了系统的应用范围。     

分布式数据库系统的安全性和防护策略的研究

分布式数据库系统是与计算机网络相结合的一个系统,随着计算机信息网络技术在社会生活中的普及,分布式数据库系统被广泛应用到社会的各个层面.然而,就目前的形式来看,分布式数据库系统还存在着一些不安全因素,本文以分布式数据库系统的安全隐患为出发点,分析了分布式数据库系统所存在的一些不安全因素,进而提出了一些相应的防范措施.     

随机控制在车辆零部件检测系统中的应用

主要介绍了车辆检测系统组成,包括主机机械系统,测量控制系统,计算机软件界面。描述了一些随机控制的数学模型。介绍一些在车辆检测系统中实际应用的随机控制算法的实现,在实际应用中的随机控制算法中,针对系统的一些经典算法的改进。     

ARM处理器与嵌入式系统

本文是作者关于嵌入式系统一些基本问题的思考和总结。主要是从嵌入式处理器与硬件、ARM处理器的优势、嵌入式软件、嵌入式系统教学等方面进行了一些梳理,谈了一些个人的观点。     

嵌入式系统在过电流保护装置中的应用

论述了一种嵌入式系统在继电保护装置中的实际应用,介绍了硬件系统的构成,软件设计的一些思路和方法.对工业应用的抗干扰设计,提出了一些见解.     

Windows系统服务纵览（三）

上两期中我们已经为大家介绍了一些Windows系统服务。不知道对大家的使用是否有所帮助,在清理系统服务的时候,面对一大堆的英文名称相信很多用户都是一头雾水,想要清理却又常常是无从下手,主要是因为我们对于Windows XP系统提供的服务并不怎么了解,所以我找了一些相关系统服务的介绍和大家分享一下,本期将继续向大家介绍一些服务的具体功能吧!以便您根据自己的实际情况选择禁用其中的一些服务,给您的Windows XP系统瘦瘦身!     

入侵检测系统的性能问题研究

首先针对现有的入侵检测系统,讨论了影响入侵检测系统性能的一些因素,然后通过分析,找到了一些相应的解决方法,最后得出结论,如果想提高入侵检测系统的性能,要全面考虑这些因素。     

带宽约束下网络化控制系统的量化研究综述

为了寻求确保系统稳定性的最小比特数,针对线性网络化控制系统,综述研究量化比特个数、系统稳定性、系统噪声之间的普遍关系的一些重要结果;针对非线性网络化控制系统,回顾一般系统中有限个量化比特能确保稳定性的一些结果;并综述了系统采取一类较普遍的非线性前馈型情况下的、一些关于能确保系统稳定性的最小比特数方面的研究,并利用仿真对...     

The computation of zones of influence of linear geological structures

The concept of a zone of influence of a linear geological structure provides a method of quantifying the effect of the structure on the properties of its neighborhood. For example, a fault may exert some influence on the local roof conditions in a mine opening, or on the location of mineral deposits, where the influence at any given distance (up to the specified half-width of the zone of influence) from the fault is estimated by some postulated influence function. Any area of interest may be partitioned into a large number of cells, and the sum of the influences due to the nearby faults calculated for the midpoint of each cell. The program groups the cells, by midpoints, into sets comprising those cells affected by precisely 0,1,2,... faults, calculates the proportion each set constitutes of the area of interest, and the total of the midpoint sums of the cells in each set. Although the program was developed for a specific problem in a New South Wales colliery, the method is not specific to this problem and has application to many situations in rock mechanics, metallogenesis, seismicity, and in other fields in which the concept of a zone of influence may be relevant.     

Estimation of probabilities of label imperfections and correction of mislabels

Schemes that use both the imperfectly labeled and unlabeled pattern sets for the estimation of probabilities of label imperfections and correction of mislabels are presented in this paper. Using relationships between the class conditional densities, and a priori probabilities with and without imperfections in the labels, the problem of estimating probabilities of label imperfections is formulated as that of minimizing the Bayes probability of error. Experimental results are presented from the processing of remotely sensed multi-spectral scanner imagery data. A thresholding scheme is proposed for the correction of pattern mislabels. For a symmetric mislabeling case, a relationship is developed between the probability that such a scheme gives a bad label to a pattern and the probability that the scheme accepts the original label of the pattern. This relationship could be used for computing the threshold from unlabeled samples for a specified probability of bad labeling. An example is presented to illustrate the behavior of the scheme. Furthermore, bounds are presented between the Bayes errors with and without imperfections in the labels and are shown to become equalities when the imperfections in the labels become symmetric.     

容错控制系统部件重要度计算的CAD算法

部件(如传感器或执行器)的失效将导致系统性能的下降甚至完全失效。因此,在设计容错控制系统时确定部件重要度是非常重要的。本文提出了部件静态和动态重要度,它们分别表示了部件失效对系统静态和动态性能的影响程度。借助仿真和矩阵转换的运算,本文提出了能同时计算m个部件静态和动态重要度的CAD算法,例子验证了该法的有效性。     

Evaluation of a set of graphic symbols

To evaluate the efficiency of a coherent set of graphic symbols for public information in railway stations, a matching procedure was used, in which a referent was specified to respondents, and they were asked to select the appropriate symbol from the complete set of symbols shown to them. Data were collected in such a way that the effects of age and travel experience could be evaluated separately. A total of 29 symbols was evaluated using 11 600 railway passengers as respondents. The results show that only half the number of symbols meet a criterion of 67% correct responses. Both increasing age and a low level of travel experience have a deteriorating effect on the understanding of the symbols. In addition to the percentage correct responses, analysis of the confusions between referents and symbols allows a more detailed assessment of the causes of a low efficiency of a symbol or a group of symbols. It is demonstrated that, based mainly on the measured confusions between symbols, proposals for the redesign of symbols can be formulated.     

Analysis of probability distribution of a random variable of an execution time of the program in the presence of random failures

The mathematical model of an estimation of an execution time of the program in the presence of random failures is studied. For decreasing of influence of failures on a program execution time the known method of checkpoints is considered. The main objective consists in reception of the formula for a distribution function of a random variable of an execution time of the program and an estimation of a quantile of the received distribution. Properties of a mean value of a random variable of an execution time of the program are studied.     

税务网络安全系统的设计

为了保证山东省某市国家税务局计算机网络中涉税信息的畅通与安全,首先对山东省某市国家税务局的网络拓扑结构和网络安全现状做了调查研究,然后针对本网络系统的特点,分析了目前可能存在的网络安全威胁,最后提出了切实可行的网络安全解决方案.通过采取以上的措施,山东省某市国家税务局的网络安全性能得到大幅提高.     

基于散乱点的任意拓扑曲面建模及绘制研究

对曲面建模进行了研究,提出了一种基于散乱点的曲面重建方法.给出三维空间的散乱点,采用3个步骤重构出三角化曲面:首先按近似共面程度对点集聚类,把接近共面的点归为同一类,然后根据空间点的邻接关系进行局部调整,最后对点集和点集之间的区域进行三角割分,得到三角化曲面,所得曲面用OpenGL进行绘制.     

On the complexity of deciding avoidability of sets of partial words

Blanchet-Sadri et al. have shown that Avoidability, or the problem of deciding the avoidability of a finite set of partial words over an alphabet of size k≥2, is NP-hard [F. Blanchet-Sadri, R. Jungers, J. Palumbo, Testing avoidability on sets of partial words is hard, Theoret. Comput. Sci. 410 (2009) 968-972]. Building on their work, we analyze in this paper the complexity of natural variations on the problem. While some of them are NP-hard, others are shown to be efficiently decidable. Using some combinatorial properties of de Bruijn graphs, we establish a correspondence between lengths of cycles in such graphs and periods of avoiding words, resulting in a tight bound for periods of avoiding words. We also prove that Avoidability can be solved in polynomial space, and reduces in polynomial time to the problem of deciding the avoidability of a finite set of partial words of equal length over the binary alphabet. We give a polynomial bound on the period of an infinite avoiding word, in the case of sets of full words, in terms of two parameters: the length and the number of words in the set. We give a polynomial space algorithm to decide if a finite set of partial words is avoided by a non-ultimately periodic infinite word. The same algorithm also decides if the number of words of length n avoiding a given finite set of partial words grows polynomially or exponentially with n.     

一类三次隐式代数曲面参数化研究

在CAGD中隐式曲面和参数曲面作为曲面的两种表示形式各有其内在的优点 ,多年来如何有效地实现二者的相互转换一直是CAGD的一个热点问题 对一类GC1拼接两个二次曲面的三次混合代数曲面进行了研究 ,提出一种基于同轴平面束与代数曲面相交的几何化参数化方法 与传统参数化方法相比 ,该方法结构直观且具有可使三次代数曲面位于 [0 ,1]× [0 ,1]参数区间内 ,以及曲面的边界位于等参数线上等特点 ,利用这种参数曲面可以方便地实现机器作图和各种操作 实验结果验证了方法的有效性     

数字化校园统一身份认证系统的设计

介绍了校园网中业务系统的现状,对校园网中整合现有系统,统一身份认证的方式进行了分析,提出了一种统一身份认证的模型,它是一种基于接口的集中式认证方式,可以方便用户对资源的访问,增强用户访问站点的安全性。详细介绍了该模型的认证过程,并对该模型的安全性进行了分析。