连续时间广义边值系统的状态结构

连续时间广义边值系统被描述为：Ｅｘ（ｔ）＝Ａｘ（ｔ）＋Ｂｕ（ｔ），Ｍｘ（Ｔ）＝η，其中Ｅ是奇异方阵；ｕ（ｔ）满足任意次可微，本文讨论了这类系统的定义，可解性及其状态结构。     

滞后不确定性系统的鲁棒控制

１主要结果本文将文［１］的结论推广到具有多重状态时滞和多重控制时滞的不确定性系统ｘ（ｔ）＝（Ａ０＋Ｂ０ΔＡ０（ｒ０（ｔ）））ｘ（ｔ）＋∑Ｎｉ＝１Ｂ０（Ａｉ＋ΔＡｉ（ｒｉ（ｔ）））ｘ（ｔ－ｄｘｉ（ｔ））＋（Ｂ０＋Ｂ０ΔＢ０（ｓ０（ｔ）））ｕ（ｔ）＋∑Ｍ...     

不确定噪声下确保连续LQG最优控制目标的扰动界

不确定噪声下确保连续ＬＱＧ最优控制目标的扰动界奚宏生杨孝先（中国科学技术大学自动化系合肥２３００２７）关键词鲁棒ＬＱＧ最优控制，确保控制目标，扰动界收稿日期１９９４－０９－０８１引言具有不确定噪声的随机线性控制系统为ｘ（ｔ）＝Ａｘ（ｔ）＋Ｂｕ（ｔ）＋...     

非对称广义特征值问题的并行同伦-行列式算法

１．引言同伦算法是七十年代开始发展起来的求解非线性问题的数值方法．它的特点表现为通常是大范围收敛，容易实施并行计算．近二十年来，同伦算法的发展主要沿两条走线展开，即单纯形法和连续法．连续同伦算法的基本思路为：设Ｘ和Ｙ是Ｒ"中的非空子集，人ｘ：Ｘ－－＋Ｙ是光滑映射，如果对Ｖ（ｔ，ｘ）Ｅ［０，１］ｘＸ有Ｈ（ｔ，ｘ）一吨（ｘ）十（１一Ｏ八：）ＥＹ成立，则称光滑映射Ｈ：［０，１］ＸＸ＋Ｙ是ｆ和９之间的一个线性同伦．连续同伦算法主要是借助于同伦Ｈ的零点集Ｈ－'（０）从平凡映射ｇ在｛１｝ｘＲ"中的零点集｛１｝…     

单滞后区间动力系统的稳定性

本文研究如下单滞后时变区间动力系统ｘ（ｔ）＝Ｎ［Ｐ，Ｑ］ｘ（ｔ）＋Ｎ［Ｃ（ｔ），Ｄ（ｔ）］ｘ（ｔ－τ），τ≥０的渐近稳定性的ａ稳定性，给出了其渐近稳定和ａ稳定的充分条件，推广和改进了文［１，２］的工作。     

离散时间不确定系统鲁棒控制的一个注记

离散时间不确定系统鲁棒控制的一个注记王海晏（华东冶金学院自动化系马鞍山２４３００２）关键词匹配条件，鲁棒控制，状态反馈，李亚普诺夫函数。１问题的提出考虑一类线性离散时间不确定系统ｘ（０一（Ａ十面Ａ（ｒＧ》）ｘ（０＋（Ｂ＋ＡＢ（ａ（０》ｕ（０＋Ｃｗ（０...     

慢时变系统：指数稳定性和稳健适应控制

本文首先给出线性慢时变系统ｘ（ｔ）＝Ａ（ｔ）ｘ（ｔ）指数稳定的一个新的充分条件，进而考虑带有未建模动态和外部干扰的连续时间适应控制闭环系统的一般形式，给出了系统稳定的一些充分条件，这一结果可作为研究各种连续时间适应控制算法稳健稳定性问题的有力工具。     

多氯联苯（PCBS）分配系数的估算和预测

基于烷烃分子距边矢量,将以原子为基准的距离－边数 量扩展为以基团为基准的距离－边数矢量。研究发现新分子距边矢量与多氯联苯正辛醇／水分配系数的对数有很好的线性关系：ｌｏｇＫｏｗ＝４．１０８８４＋０．５２４２３７ｕ１－０．０９２９０６２ｕ２ｎ＝３７,ｒ＝０．０９９０８,Ｓ＝０．１７７５,ＥＶ＝０．９８１１,Ｆ＝１８６８。     

VFP5.0中控制Excel的一种方法

本文讲述了在 ＶＦＰ５．０中,通过 ＯＬＥ自动执行对象（ Ｏｂｊｅｃｔ Ｌｉｎｋｉｎｇ Ｅｍｂｅｄｄｉｎｇ Ａｕｔｏｍａｔｉｏｎ）技术直接控制Ｅｘｃｅｌ的一种方法。利用这一方法,可在ＶＦＰ５．０中设计一系列按钮,直接控制平台中的Ｅｘｃｅｌ应用系统,将ＶＦＰ５．０中的数据传送到Ｅｘｃｅｌ中,产生工作薄、统计图、存储、打印等操作。     

不确定线性组合大系统的二次稳定性、 联结稳定性H∞小增益定理

本文首先讨论了不确定线性系统ｘ＾．（ｔ）＝｛Ａ＋＾ｋΣｉ＝１ＤｉＦｉ（ｔ）Ｅ｝ｘ（ｔ）的二次稳定性,得到了该系统是二次稳定的充分必要条件。基于本文得到的结论讨论了不确定线性组合大系统的二次稳定性和联结稳定问题,得到了用关于低阶子系统的一组Ｈ∞模描述了大系统稳定性的充分条件。     

Second-order two-point boundary value problems using the variational iteration algorithm-II

In this paper, we introduce an improved variational iteration method (VIM) for nonlinear second-order boundary value problems. The main advantage of this modification is that it can avoid additional computation in determining the unknown parameters in initial approximation when solving boundary value problems using the conventional VIM. Also, iterative sequences obtained using the improved VIM do satisfy the boundary conditions while iterative sequences obtained using conventional VIM may not, in general, satisfy the boundary conditions. Numerical results reveal that the improved method is accurate and efficient.     

Implicit midpoint rule and extrapolation to singularly perturbed boundary alue problems

Linear singularly perturbed boundary value probleme εy″?py = f(x), y(0) = y(l) = 0 is solved numerically by reducing to the first order linear system and applying the implicit midpoint rule on equidistant meshes. Using the asymptotic expansion of the global error, the second order of convergence is improved by Richardson extrapolation when h ²≤ε. Some numerical examples are given in illustration of this theory.     

Periodic smoothing splines

Periodic smoothing splines appear for example as generators of closed, planar curves, and in this paper they are constructed using a controlled two point boundary value problem in order to generate the desired spline function. The procedure is based on minimum norm problems in Hilbert spaces and a suitable Hilbert space is defined together with a corresponding linear affine variety that captures the constraints. The optimization is then reduced to the computationally stable problem of finding the point in the constraint variety closest to the data points.     

Exploratory Navigation Based on Dynamical Boundary Value Problems

The paper presents a general framework for concurrent navigation and exploration of unknown environments based on discrete potential fields that guide the robot motion. These potentials are obtained from a class of partial differential equation (PDE) problems called boundary value problems (BVP). The boundaries are generated from sensor readings and therefore they change as the robot moves. This framework corresponds to an extension of our previous work (Prestes, E., Idiart, M. A. P., Engel, P. and Trevisan, M.: Exploration technique using potential fields calculated from relaxation methods, in: IEEE/RSJ International Conference on Intelligent Robots and Systems, 2001, p. 2012; Prestes, E., Engel, P. M., Trevisan, M. and Idiart, M. A.: Exploration method using harmonic functions, Robot. Auton. Syst. 40(1) (2002), 25–42). Here, we propose that a careful choice of the PDE and the boundary conditions can produce efficient exploratory behaviors in sparse and dense environments. Furthermore, we show how to extend the exploratory behavior to produce new ones by changing dynamically the boundary function (the value of the potential at the boundaries) as the exploration takes course. Our framework is validated through a series of experiments with a real robot in office environments.     

Numerical solution of nonlinear system of second-order boundary value problems using cubic B-spline scaling functions

A numerical technique is presented for the solution of nonlinear system of second-order boundary value problems. This method uses the cubic B-spline scaling functions. The method consists of expanding the required approximate solution as the elements of cubic B-spline scaling function. Using the operational matrix of derivative, we reduce the problem to a set of algebraic equations. Numerical examples are included to demonstrate the validity and applicability of the technique. The method is easy to implement and produces very accurate results.     

基于神经网络的微分对策控制器设计

采用伴随－BP技术，将微分对策的两点边值求解问题转化两个神经网络的学习问题，训练后的两个神经网络分别作为对策双方的最优控制器在线使用，避免了直接求解复杂的两点边值问题，对追逃微分对策问题的仿真结果表明，该方法对初始条件和噪声具有较好的鲁棒性。     

连续广义系统多点边值问题解的结构

本文在多点边值的约束条件下，讨论了连续广义控制系统解的存在唯一性及解的结构。并用Ｇｒｅｅｎ函数给出了解的表达式。     

The iterated defect correction methods for singular two-point boundary value problems

In this paper, the iterated defect correction (IDeC) techniques based on the centered Euler method for the equivalent first order system of the singular two-point boundary value problem in linear case (x ^α y′(x))′ = f(x), y(0) = a,y(1) = b, where 0 < α < 1 are considered. By using the asymptotic expansion of the global error, it is analyzed that the IDeC methods improved the approximate results by means of IDeC steps and the degree of the interpolating polynomials used. Some numerical examples from the literature are given in illustration of this theory.     

Quintic nonpolynomial spline method for the solution of a second-order boundary-value problem with engineering applications

Nonpolynomial quintic spline functions are used to develop a numerical algorithm for computing an approximation to the solution of a system of second order boundary value problems associated with heat transfer. We show that the approximate solutions obtained by our algorithm are better than those produced by other spline and domain decomposition methods. A comparison of our algorithm with nonpolynomial quadratic spline method is discussed with the help of two numerical examples.