Using linear models in optimizing parameters of time-triggered protocols

A mechanism of synchronization of components of distributed systems in which communications are based on a common time schedule for all system components is illustrated by examples of simple Time-Triggered Protocols. For parametric linear models of synchronization, the optimization problem is considered for a parameter that should exclude the overlapping of messages in communication channels. The results of using numeric methods for estimation of the optimal value of this parameter are described. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 24–32, May–June 2006.     

A method to find all solutions of a system of multivariate polynomial equalities and inequalities in the max algebra

In this paper we show that finding solutions of a system of multivariate polynomial equalities and inequalities in the max algebra is equivalent to solving an Extended Linear Complementarity Problem. This allows us to find all solutions of such a system of multivariate polynomial equalities and inequalities and provides a geometrical insight in the structure of the solution set. We also demonstrate that this enables us to solve many important problems in the max algebra and the max-min-plus algebra such as matrix decompositions, construction of matrices with a given characteristic polynomial, state space transformations and the (minimal) state space realization problem.Research assistant with the N.F.W.O. (Belgian National Fund for Scientific Research).Senior research associate with the N.F.W.O.     

莺-琼盆地的独特埋藏史

通过沉积速率线性外推剥蚀厚度恢复、脱压实和异常高压以及古水深校正的单井埋藏史和连井埋藏剖面及构造沉降分析,发现莺-琼盆地是个多旋回沉积盆地,其沉积物埋藏过程可分为早期缓慢浅埋和晚期快速深埋两大阶段.这种独特的埋藏历史不仅是储层孔隙增生与保存的主要控制因素之一,而且极大地影响了烃源岩于酪根热解反应路径、烃类的运移和聚集,异常高压的发育以及所发生的复杂的水(气)—岩相互作用.涸11-4油田位于南海北部湾盆地涸西南凹陷,距广西北海市103km,离涸10-3油田17km.油田于1993年9月19日投产,目前开发形势较好,产量、压力稳定.在开发实践中我们体会到,要提高油田开发水平,搞好油藏监测是非常重要的.1钻井和完井过程中的油藏监测     

鲁棒输出反馈控制系统设计

本文利用文献[10]中提出的线性系统特征结构配置结果和Hellman-Feynman定理,导 出了输出反馈系统闭环极点关于开环矩阵中受扰元素灵敏度的参数表达式,并在此基础上给 出了具有最小闭环极点灵敏度的输出反馈控制系统设计的一个算法.该算法简单、有效,且具 有较好的"最优性".     

以数字搜索树表示的二值图象的几何变换

本文介绍以数字搜索树表示的二值图象的一种几何变换算法，文中讨论了四分区与正四边区的基本关系，输出ＤＳＴ结点成立的充分条件，给出了完整的几何变换算法并对算法的复杂性作了分析。     

Input-output finite-time stability of time-varying linear singular systems

This paper studies the input-output finite-time stabilization problem for time-varying linear singular systems. The output and the input refer to the controlled output and the disturbance input,respectively.Two classes of disturbance inputs are considered,which belong to L-two and L-infinity.Sufficient conditions are firstly provided which guarantee the input-output finite-time stability.Based on this,state feedback controllers are designed such that the resultant closed-loop systems are input-output finite-time stable.The conditions are presented in terms of differential linear matrix inequalities.Finally,an example is presented to show the validity of the proposed results.     

Stability analysis for discrete linear systems with state saturation by a saturation-dependent Lyapunov functional

This paper concerns the stability analysis problem of discrete linear systems with state saturation using a saturation-dependent Lyapunov functional.We introduce a free matrix characterized by the sum of the absolute value of each elements for each row less than 1,which makes the state with saturation constraint reside in a convex polyhedron.A saturation-dependent Lyapunov functional is then designed to obtain a sufficient condition for such systems to be globally asymptotically stable.Based on this stability criterion,the state feedback control law synthesis problem is also studied.The obtained results are formulated in terms of bilinear matrix inequalities that can be solved by the presented iterative linear matrix inequality algorithm.Two numerical examples are used to demonstrate the effectiveness of the proposed method.     

基于Matlab的线性规划问题求解

线性规划是运筹学中研究较早、发展较快、应用广泛、方法成熟的一个重要分支,它是辅助人们进行科学管理的一种重要的数学方法.文章首先介绍了线性规划的基本概念及标准形式,着重讨论了线性规划问题的三种常用解法:单纯形法、直接搜索法以及遗传算法,最后在Matlab R2009a环境下进行了仿真.通过结果可以看出,用Matlab求解线性规划问题,可以避免手工的烦琐计算,大大地提高工作效率和结果的准确性.     

基于双正交小波和加权NLDA的人脸识别

文章针对基于零空间线性判别分析方法在高维多类别的人脸识别应用中存在的“次优性”和“效率低”两个问题,提出了一种改进方法.该方法用加权函数重新定义类间离散矩阵以减弱边缘类带来的不良影响来改善次优性问题;并对图像进行双正交小波分解来降低分辨率以到达提高效率的目的.最后在ORL人脸库上进行了实验,通过实验确定了最优加权系数和小波分解的最佳层数,并验证了该方法比基于零空间线性判别分析方法有更高的效率和识别率.     

An iterative linear quadratic regulator based trajectory tracking controller for wheeled mobile robot

We present an iterative linear quadratic regulator(ILQR) method for trajectory tracking control of a wheeled mobile robot system.The proposed scheme involves a kinematic model linearization technique,a global trajectory generation algorithm,and trajectory tracking controller design.A lattice planner,which searches over a 3D(x,y,θ) configuration space,is adopted to generate the global trajectory.The ILQR method is used to design a local trajectory tracking controller.The effectiveness of the proposed method is demonstrated in simulation and experiment with a significantly asymmetric differential drive robot.The performance of the local controller is analyzed and compared with that of the existing linear quadratic regulator(LQR) method.According to the experiments,the new controller improves the control sequences(v,ω) iteratively and produces slightly better results.Specifically,two trajectories,’S’ and ’8’ courses,are followed with sufficient accuracy using the proposed controller.