Robust model predictive control of continuous uncertain systems*

The authors concern robust model predictive control for linear continuous systems with polytopic uncertainties and input constraints. At each sampling time, a piecewise constant control sequence is obtained by solving a set of linear matrix inequalities. The sufficient conditions on the existence of the model predictive control are given, and the robust stability of the closed-loop systems is guaranteed. A simulation example illustrates the efficiency of the proposed method.     

基于凸多面体不确定网络化系统的鲁棒无源滤波

研究一类同时具有时变时延和测量数据丢失的不确定网络化系统的鲁棒无源滤波器设计问题。时变时延假设在一个已知的界内随机变化。测量数据的丢失是随机发生的,假设满足Bernoulli分布随机序列。采用线性矩阵不等式方法,给出了全阶和降阶的鲁棒无源滤波器存在的充分条件。所设计的滤波器使得滤波误差系统是均方指数稳定并满足给定的无源指标。最后数值仿真表明所提方法的有效性。     

Coordination Model Research Based on Command Decision Joint Intension

Command Decision Simulation （CDS） is not only an important and difficult issue in the field of simulation, but also a technique issue to be tackled in the course of collective Modeling and Simulation in Joint Operations Experiment Center. CDS can give support to all kinds of simulation. Using computer to realize the Blue side＇s command deci- sion automatic execution in the operation training simulation system can improve training effect. Using computer to realize the lower level command unit＇s automatic command deci- sion can help to reduce the number of controllers and release them from heavy work. It can also enlarge simulation scale and increase the freedom of the simulation entity especially the command entity, thus enhance the authenticity and credibility of the simulation. Ac- cording to the command decision structure and the Joint Intention Theory, the thesis puts forward the method of making use of Coordination Matrix （CM） to realizing cooperation among the entities in CDS and constructs the calculation sketch of Task Execution, Task Monitoring and Task Replanning. At the same time, the thesis brings forward the CDS structure vision based on Partial Global Planning（PGP）. As CM is an indispensable part of combat simulation, the theory and the method of CDS will become an important part for the theory of Combat Simulation.     

基于快速鲁棒性特征的景象匹配

针对光电成像制导景象匹配中图像产生较大几何形变的问题,提出了一种基于快速鲁棒性特征(speeded up robust feature, SURF)的景象匹配算法。SURF提取的图像特征具有尺度和旋转不变性,对灰度不敏感,并能快速运算。算法首先利用仿射变换对基准图像进行3D视角补偿,模拟基准图像在不同视角下的成像,以减小基准图像和实时图像间的视角差异,分别提取两图像的SURF特征,然后根据最小欧氏距离准则提取两图像间匹配的SURF特征点对,根据该特征点对估计基础矩阵,得到两图像的投影关系。仿真结果表明,该算法能够适应光电成像制导中图像的几何形变,实现稳定的景象匹配。     

Robust H∞ filtering for discrete-time systems with Markovian switching and time-delays

The robust H∞ filtering problem for uncertain discrete-time Markovian jump linear systems with modedependent time-delays is investigated. Attention is focused on designing a Markovian jump linear filter that ensures robust stochastic stability while achieving a prescribed H∞ performance level of the resulting filtering error system, for all admissible uncertainties. The key features of the approach include the introduction of a new type of stochastic Lyapunov functional and some free weighting matrix variables. Sufficient conditions for the solvability of this problem are obtained in terms of a set of linear matrix inequalities. Numerical examples are provided to demonstrate the reduced conservatism of the proposed approach.     

一种新颖的基于NMF的人脸识别方法

提出了一种新颖的基于非负矩阵分解(NMF)进行人脸识别的方法,读方法首先对人脸图像作NMF得到由人脸基图像组成的子空间矩阵及其对应的系数矩阵,然后将其重构获得NMF重构人脸图像,进而从原始图像中减去重构图像以获取残差图像.最后对残差图像作局部非负矩阵分解(LNMF)以提取其非负子空间及其系数矩阵,并将两次得到的系数矩阵混合,根据最近邻原则进行识别.在ORL标准人脸数据库上的实验表明,该方法具有更好的识别率.     

Analysis of finite-time practical stability for time-varying polytopic systems

The problem of finite-time practical stability (FTPS) for time-varying polytopic systems is discussed. Three equivalent conditions for FTPS are first proposed. To facilitate the system analysis, a sufficient linear matrix inequality (LMI) criterion on the FTPS is further provided. The definition of finite-time practical boundedness and a sufficient LMI criterion are also provided to overcome the exogenous disturbance. A numerical example is used to illustrate the effect of the proposed approach.     

Capacity analysis of high-rank line-of-sight MIMO channels

Matrix perturbation theory is utilized to investigate high-rank line of sight multiple input multiple output channels in a microwave relay system. The upper and lower bounds of channel capacity are derived based on space time block codes technique and singular values decomposition. A useful constraint for designing LOS MIMO channels is developed by the use of the condition number of the MIMO channel matrix. The theoretical analysis of channel capacity is confirmed by the simulation. The results show that the proposed method is able to give a physical explanation of the high-rank LOS MIMO channel matrix characteristics.     

一种结合形状上下文分析的Laplace谱匹配算法

提出了一种结合形状上下文分析的Laplace谱匹配算法.工作主要侧重于如何提高Laplace谱匹配算法对点的位置随机抖动的鲁棒性.首先,使用Laplace矩阵的特征向量和特征值以及双随机矩阵的方法计算初始匹配概率.然后,借助于概率松弛算法,将用形状上下文表示的局部相似性融入Laplace谱匹配算法以优化谱匹配的结果.对真实和合成数据的实验表明该方法具有比较高的精度.     

不确定T-S模糊广义系统基于观测器的无源控制

针对一类范数有界不确定性T-S模糊广义系统,研究了其在满足不确定性的基于观测器的无源控制器的设计问题.在状态不可测的情况下给出了使得闭环系统广义二次稳定且无源的基于观测器的控制器存在的充分条件和设计方法.通过求解若干线性矩阵不等式,获得系统的观测增益与控制增益.最后通过数值仿真例子,说明所提出的设计方法可行、有效.