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71.
Dissipative control systems synthesis with full state feedback 总被引:2,自引:0,他引:2
S. Yuliar M. R. James J. W. Helton 《Mathematics of Control, Signals, and Systems (MCSS)》1998,11(4):335-356
In this paper we present a general framework for synthesizing state feedback controllers to achieve any desired closed loop
dissipative behavior. Special cases include positive real andH
∞ controller synthesis. We show that the solution to this dissipative controller synthesis problem is equivalent to the existence
of a solution to a partial differential inequality (nonlinear systems case) or an algebraic Riccati inequality (linear systems
case). Stability results can be obtained under appropriate detectability assumptions, and a generalization of the strict bounded
real lemma is given. We also present an application of the results to a robust stabilization problem.
This work was supported by the Cooperative Research Centre for Robert and Adaptive Systems (CRASys), Australia. 相似文献
72.
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74.
该文通过EMIP—ATP仿真软件,模拟计算了GIS局部放电信号在一个线路间档上的传播情况,为实际GIS局部放电的检测和定位提供了一个理论依据。并把联合时频分析方法应用到GIS局部放电信号的分析与处理上,取得了良好的效果。 相似文献
75.
基于数学形态滤波器抑制局部放电窄带周期性干扰的研究 总被引:29,自引:7,他引:29
变压器局部放电在线检测的关键技术之一是有效抑制现场强烈的电磁干扰。文中引入非线性数学形态学变换,基于最小均方(LMS)算法构造了一种结构元素自适应的形态开、闭组合形态滤波器,很好地解决了局部放电在线检测的窄带周期性干扰问题。仿真表明该方法对窄带周期性干扰的噪声抑制比(NNR)大于60dB,而现场实际测量的噪声抑制比超过20dB。数学形态滤波器为电力变压器局部放电在线检测提供了一种新的干扰抑制方法。 相似文献
76.
This paper is concerned with the partial difference equation Am+1,n+Am,n+1−Am,n+pm,nAm−k,n−l=0,m,n=0,1,2,…,, where k and l are two positive integers, {pm,n} is a real double sequence. Some new oscillation criteria for this equation are obtained. 相似文献
77.
This paper investigates the benefits that the partial least squares (PLS) modelling approach offers engineers involved in the operation of fed-batch fermentation processes. It is shown that models developed using PLS can be used to provide accurate inference of quality variables that are difficult to measure on-line, such as biomass concentration. It is further shown that this model can be used to provide fault detection and isolation capabilities and that it can be integrated within a standard model predictive control framework to regulate the growth of biomass within the fermenter. This model predictive controller is shown to provide its own monitoring capabilities that can be used to identify faults within the process and also within the controller itself. Finally it is demonstrated that the performance of the controller can be maintained in the presence of fault conditions within the process. 相似文献
78.
针对变压器绝缘的在线检测,在对油中溶解气体的分析中,介绍了三比值法及故障性质的判断、油中溶解气体及总烃产气速率的应注意值;在对局部放电的分析中,介绍了电气法、超声法以及电—超声联合法;在对变压器绕组变形的检测中,介绍了短路阻抗法、低压脉冲法、频率响应法。 相似文献
79.
无线传感网络WSNs(Wireless Sensor Networks)已广泛应用于各类领域.然而,由于能量有限,提高传感节点能效是一项挑战工作.休眠调度策略是保存能量、延长网络寿命的有效策略.此外,多数WSNs应用并不要求100%的覆盖.为此,提出面向部分覆盖应用的节点唤醒机制,且标记为PCLA.PCLA机制引用学习自动机去合理地唤醒节点,而其他节点休眠,进而延长网络寿命.首先,唤醒部分节点构成主干网,然后,再利用这些节点的邻居去满足网络覆盖要求.实验数据表明,与同类机制相比,提出的PCLA机制能够有效地满足部分覆盖要求,并且在活动节点数和网络寿命方面也具有较好的性能. 相似文献
80.
The information of soil composition and its spatial distribution could be obtained quickly and efficiently by using spectral technology.In order to accurately estimate the content and distribution characteristics of soil Fe elements in the loess plateau,the typical loess in the eastern part of Yulin was collected in the field.Laboratory physical and chemical analysis,spectral determination and pretreatment,analysis of the correlation between soil iron content and reflection spectrum,screening sensitive bands,using partial least squares modeling to determine the best estimation model.The spectral reflectivity and the selected sensitive bands are mainly distributed at 500 nm,870 nm,1 700 nm and 2 200 nm.The original reflectivity(Ref) modeling results are relatively stable and the prediction effect is the best.The prediction set correlation coefficient R2 is up to 0.73 and the Root Mean Square Error(RMSEP) is the smallest.After derivative transform(FDR and SDR) and continuum removal of CR transform,the prediction set R2 is 0.61 and 0.64,respectively.The optimal estimation model of soil Fe content(Ref) was applied to the Sentinel-2 multi-spectral remote sensing image to obtain the remote sensing inversion map of soil Fe content by band interpolation.It was found that the distribution characteristics of soil Fe content in the studied area were closely related to the strata.The results of this study can provide support for remote sensing analysis of soil Fe element content and realize rapid spectral mapping of soil iron in the Loess Plateau. 相似文献