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1.
给出了一种零件特征描述和信息模型建立方法。首先对具体零件特征进行分析,在此基础上,针对性的给出零件特征描述方法,然后根据模型信息结构,给出模型的总体结构。该方法简单方便、实用性强。  相似文献   

2.
非规则三维数据的曲面拟合方法   总被引:1,自引:0,他引:1       下载免费PDF全文
给出了一种非规则三维数据的曲面拟合方法,该方法给出的网络模型不需要删除奇异数据,从而可以保持数据信息的完整性,此外,该方法给出的拟合曲面平滑,连续性好,局部细节丰富,且处处可偏导。  相似文献   

3.
研究了同时存在传输受限和随机丢包情况下的网络化控制系统的故障检测问题, 给出了残差发生、残差评价和误报率分析的方法. 首先, 基于确定性的系统描述, 本文给出了基于周期系统理论的残差发生方法. 接下来, 在充分利用随机丢包概率特性的基础上, 本文给出了残差评价方法. 最后, 利用切比雪夫不等式, 本文给出了故障检测误报率的计算方法. 仿真结果证实了算法的有效性.  相似文献   

4.
该文给出了数据抽取过程中需要的基本定义,描述了数据抽取所基于的页面生成模型。同时给出了EXALG+这种数据抽取方法的基本流程,并给出了这种方法的抽取流程图。  相似文献   

5.
提出了基于flashMX和authorware的混合编程方法,给出了混合编程的关键――变量传递的方法,并给出相应范例。  相似文献   

6.
广义时滞系统的降维观测器设计   总被引:1,自引:0,他引:1  
讨论广义时滞系统的降维观测器的设计方法.通过引入矩阵的广义逆矩阵,给出在一定条件下降维观测器的具体形式,然后分别利用广义逆矩阵及Lyapunov函数方法给出这些条件成立的具体条件及验证方法。最后给出一个例子来说明方法的有效性。  相似文献   

7.
针对一类离散的不确定切换模糊组合系统,利用平行分布补偿算法(PDC)给出分散切换模糊控制器的设计方法,利用多Lyapunov函数方法,给出使系统稳定且H∞控制问题可解的矩阵不等式条件,并给出分散切换律设计.仿真结果表明方法的有效性.  相似文献   

8.
有限识别器的最小化方法   总被引:1,自引:1,他引:0       下载免费PDF全文
给出确定型有限识别器最小化的一种方法,并给出一类非确定型有限识别器最小化的方法。  相似文献   

9.
输入输出双线性系统的递推辨识与实现算法   总被引:1,自引:1,他引:0  
本文对输入输出双线性系统给出了一套完整的辨识方法。首先给出了输入输出方程的一般形式,并对于一类规范型给出了相应地输入输出差分方程。然后给出了确定系统的结构指标和参数估计的递推算法,它改进了由Katta和Nurges(1984)给出的方法,大大缩短了计量时间。另外,还给出了状态方法的简单实现算法。最后,给出了仿真例子说明算法的有效性。  相似文献   

10.
陈锐 《微机发展》2006,16(8):30-34
在多维数据压缩的基础上,提出了多维数据的CUBE计算方法。首先给出了无限内存算法,其次给出了一个不完全立方体算法,最后给出了完整立方体的计算方法。并与其他CUBE算法作了比较。  相似文献   

11.
For the analysis of heavily stochastically disturbed, linearizable control systems by means of predetermined test signals, measuring strategies are derived which ensure a short measuring time for the analysis with a prescribed accuracy and given technical limitations. The time favourable analysis strategy is obtained by resolving an isoperimetric variation problem with inequality constraints and a super-ordinated optimizing problem. A digital computer is utilized to calculate the optimum analysis strategy. An example is given which demonstrates the application of the programmed ALGOL algorithms.  相似文献   

12.
基于自动机理论的分布式实时调度分析工具   总被引:1,自引:0,他引:1  
桂盛霖  罗蕾  李允  于淼  徐建华 《软件学报》2011,22(6):1236-1251
分布式实时系统是广泛应用在众多关键领域的一类复杂实时系统.为保证其上运行任务的实时性,传统基于最坏响应时间的调度分析方法往往包含了实际系统运行过程中无法达到的最坏情况,因此在这些情况下的分析结果过于悲观.基于自动机理论的模型检测方法的好处在于能够穷尽地搜索整个系统状态空间,得到精确的分析结果.为了利用形式化方法的优势来...  相似文献   

13.
A graph-based modeling technique has been developed for the stochastic analysis of systems containing concurrency. The basis of the technique is the use of directed acyclic graphs. These graphs represent event-precedence networks where activities may occur serially, probabilistically, or concurrently. When a set of activities occurs concurrently, the condition for the set of activities to complete is that a specified number of the activities must complete. This includes the special cases that one or all of the activities must complete. The cumulative distribution function associated with an activity is assumed to have exponential polynomial form. Further generality is obtained by allowing these distributions to have a mass at the origin and/or at infinity. The distribution function for the time taken to complete the entire graph is computed symbolically in the time parameter t. The technique allows two or more graphs to be combined hierarchically. Applications of the technique to the evaluation of concurrent program execution time and to the reliability analysis of fault-tolerant systems are discussed.  相似文献   

14.
Real-time systems are becoming increasingly widespread, often in safety-critical applications. It is therefore crucial that these systems be correct; however, there are few automated tools for analyzing concurrency and timing properties of these systems. The PARTS toolset uses a Petri-net-based reachability analysis to analyze program specifications written in an Ada-83 subset. Our simple time Petri nets are specifically aimed at facilitating real-time analysis. In order to control the state-explosion problem, PARTS employs several optimization techniques aimed at state-space reduction. In this paper we discuss our approach and we report on extensive experiments with several examples of real-time specifications based on Ada 83. When possible, we also compare our experimental results with results obtained by other approaches to real-time analysis.  相似文献   

15.
This paper presents a new method of analysis of bilinear systems via the single-term Walsh series (STWS). The STWS method has definite advantages over the Walsh function (WF) method and block-pulse function (BPF) method. Both the discrete values and block-pulse values of the results are obtained for any length of time and selecting any positive integer as the number of intervals. The recursive relations are simple and save both computer time and storage. Illustrative examples are presented.  相似文献   

16.
基于MATLAB GUI的信号与系统分析软件开发   总被引:2,自引:0,他引:2  
借助MATLAB的信号处理工具和GUI图形用户界面功能设计并开发了一款信号与系统分析软件.软件平台包括了连续信号与系统的时域分析方法和变换域分析方法,以及离散时间信号与系统的时域分析方法和Z域分析方法等信号与系统中的主要内容.该软件可以帮助学生完成复杂的数学运算,使得复杂抽象的理论变得简单直观.  相似文献   

17.
张渝  刘枫 《计算机科学》2007,34(4):265-268
IEC61499功能块逐渐被工业采纳。本文针对分布式功能块控制应用(DFBCA)缺乏性能分析方法的情况,提出了一种基于随机Petri网的DFBCA性能分析方法。该方法以DFBCA的运行状态为着手点,利用Petri网易于表示系统中可能发生的各种状态变化及其关系的特点,将DFBCA转换为随机Petri网模型。再利用随机Petri网模型与马尔可夫链(MC)同构的特征,将随机Petri网模型转换为MC。得到的MC为DFBCA的性能分析提供了数学基础。最后基于MC的状态转移矩阵和稳态概率,对在每个状态中的驻留时间、变迁的利用率、变迁的标记流速、子系统延时时间等性能指标进行了分析。通过具体的示例说明了这种性能分析方法的可行性。  相似文献   

18.
Sensitivity Analysis of Rigid-Flexible Multibody Systems   总被引:1,自引:0,他引:1  
An important step in the application of automated design techniques to rigid-flexible multibody systems is the calculation of the sensitivities with respect to design variables. Thispaper presents a general formulation for thecalculation of the first order analytical designsensitivities based on the direct differentiationmethod. The analytical sensitivities are comparedwith the numerical results obtained by the finitedifferences method and the accuracy and validity ofboth methods is discussed. Cartesian co-ordinates areused for the dynamic analysis of rigid-flexiblemultibody systems. To reduce the number ofco-ordinates associated with the flexible bodies, thecomponent mode synthesis method is used. Theequations of the sensitivities are obtainedsymbolically and integrated in time simultaneouslywith the dynamic equations. Examples of 2Dsensitivity analysis of the transient response of aslider-crank and of a vehicle with a flexible chassisare presented, and the accuracy and characteristics ofthe sensitivities are analyzed and discussed.  相似文献   

19.
实时任务可调度分析是保证实时系统正确性的重要手段之一,目前现有的基于周期性任务模型的确定性分析方法比较保守,不适合于多媒体,通讯等软实时系统的可调度性分析,本文提出一个基于概率的分析方法,以概率的形式对系统中实时任务的可调度性进行分析。  相似文献   

20.
Response Time Analysis of Asynchronous Real-Time Systems   总被引:1,自引:0,他引:1  
In asynchronous real-time systems the time when all events occur can not be predicted beforehand. Systems with sporadic tasks, or that operate a protocol for sharing resources like the priority ceiling protocol, for example, are asynchronous real-time systems. In this paper, we present a sufficient and efficient response time based analysis technique for computing R i(k), the worst case response time at each invocation k of the periodic tasks of real-time asynchronous systems. In addition, efficient idle time computation for asynchronous systems is presented. This analysis technique can be applied to the analysis of several process models including weakly hard real-time systems, and slack management techniques like aperiodic servers and slack stealing algorithms. It is also shown that the pattern of response times of tasks in a hyperperiod is pseudoperiodic and that the maximum response time instants tend to occur evenly separated within the hyperperiod.  相似文献   

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