排序方式: 共有54条查询结果,搜索用时 15 毫秒
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FDPM和FOOJA是目前两种最为有效的适用于主、次子空间跟踪的方法,属于低复杂度算法。进一步降低算法运算复杂度,对保证算法的实时性具有非常重要的意义。以降低算法运算复杂度为背景,通过对FDPM、FOOJA算法的分析,指出存在两种简化运算量的FDPM1stcol、FOOJA1stcol方法。在有限精度运算条件下,对四种方法的稳定性、数值鲁棒性进行了深入分析和讨论。通过实验仿真,对分析的结论进行了验证。 相似文献
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针对直流位置伺服系统,提出了一种改进型IMC-PI控制方法。引入作用函数,并将其与IMC-PI控制器串联,构成改进型PI控制器,其中IMC-PI控制器根据内模控制原理进行设计,作用函数为系统偏差的微分表达式,其阶次的选择应保证系统开环传递函数为严格正则。改进IMC-PI控制可使系统的调节过程分为作用函数趋近零和保持为零的两个阶段,从而保证系统偏差按照作用函数等于零确定的轨迹趋近于零。仿真结果表明所提方法可使系统具有良好的动态响应性能和鲁棒性。另外,利用Qstudio RP实验平台跟随跟随1+sin(10t)rad正弦信号时,IAE为0.14 rad·s,实验结果表明该方法可有效改善伺服系统的性能。 相似文献
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常规的特征结构配置(EA)方法不能同时满足系统频域设计指标和鲁棒稳定性的要求,而H_∞鲁棒控制理论在设计控制器时,并没有考虑系统时域性能。为此,基于特征结构配置和H_∞鲁棒控制,设计一种直观的控制器。该控制器以特征结构配置作为内环控制器,以H_∞鲁棒控制器作为外环控制器,使闭环系统能同时获得较好的时域动态特性、鲁棒稳定性以及指令跟踪性能力。通过对某无人机横侧向飞行控制的仿真,进一步验证了该方法的有效性。 相似文献
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针对复杂海空背景图像中的海天线检测问题,提出了一种基于相位编组和灰度统计的新方法.首先,在边缘图像的基础上运用相位编组算法,得到大量的直线段.然后,根据直线段的图像倾角和到图像原点的距离两个参数对这些直线段进行分类,并选取直线段长度总和最大的若干个类,用这些类中的所有边缘点进行直线拟合,得到若干条候选海天线.最后,通过... 相似文献
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A mathematical formulation of an optimization model designed to select projects for inclusion in an R&D portfolio, subject to a wide variety of constraints (e.g., capital, headcount, strategic intent, etc.), is presented. The model is similar to others that have previously appeared in the literature and is in the form of a mixed integer programming (MIP) problem known as the multidimensional knapsack problem. Exact solution of such problems is generally difficult, but can be accomplished in reasonable time using specialized algorithms. The main contribution of this paper is an examination of two important issues related to formulation of project selection models such as the one presented here. If partial funding and implementation of projects is allowed, the resulting formulation is a linear programming (LP) problem which can be solved quite easily. Several plausible assumptions about how partial funding impacts project value are presented. In general, our examples suggest that the problem might best be formulated as a nonlinear programming (NLP) problem, but that there is a need for further research to determine an appropriate expression for the value of a partially funded project. In light of that gap in the current body of knowledge and for practical reasons, the LP relaxation of this model is preferred. The LP relaxation can be implemented in a spreadsheet (even for relatively large problems) and gives reasonable results when applied to a test problem based on GM's R&D project selection process. There has been much discussion in the literature on the topic of assigning a quantitative measure of value to each project. Although many alternatives are suggested, no one way is universally accepted as the preferred way. There does seem to be general agreement that all of the proposed methods are subject to considerable uncertainty. A systematic way to examine the sensitivity of project selection decisions to variations in the measure of value is developed. It is shown that the solution for the illustrative problem is reasonably robust to rather large variations in the measure of value. We cannot, however, conclude that this would be the case in general. © 2001 John Wiley & Sons, Inc. Naval Research Logistics 48: 18–40, 2001 相似文献
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面空导弹武器系统软件的健壮性设计是软件开发工作的核心问题之一。首先介绍了面空导弹武器系统软件的特点并阐述了软件健壮性的内涵 ,表明它是软件可靠性、安全性和协调性均要满足的一种软件质量特性。在此基础上 ,提出了一种软件健壮性设计的概念 ,重点论述了软件可靠性设计、安全性设计和协调性设计的方法。 相似文献