网络调度中的能控性与能观性研究

为了研究网络调度对能控性与能观性的影响,对输入、输出通道都存在通信约束的网络控制系统的调度进行建模;利用通信序列表示通道的调度情况,最终将模型转化为离散切换系统;在静态调度下,利用循环不变子空间理论及其相关的性质,给出了网络控制系统能控性、能观性成立的充要条件,并给出了原有控制系统与经网络静态调度后的系统之间能控性、能观性的关系;最后用仿真实例说明了所提结论的正确性。     

分数阶扩散系统子区域能控性研究的现状与发展

近年来,随着分数阶微积分理论研究的不断深入,分数阶扩散系统因更有效描述自然界和工程中的反常扩散现象而引起了学者们的广泛关注,并取得了较为丰硕的研究成果.然而,据作者所知,目前鲜有文献总结分数阶扩散系统子区域能控性研究的相关内容.因此,本文首先详细综述分数阶扩散系统能控性、子区域能控性的研究进展,并予以分析;然后给出仍需解决的问题和可能的研究机遇.     

关于一类混合动态系统能控性与镇定的研究:一个例子

线性切换系统是一类重要的混合动态系统模型. 线性切换系统的镇定是一个基本研究问题. 针对一个线性切换系统的具体例子, 分析能控性和可镇定性的关系. 指出能控的线性切换系统是可以通过定常状态反馈镇定的.     

线性时变广义系统的能控性与能观性问题

讨论了线性时变系统和线性时变广义系统的两个基本问题, 得到了两种判定时变系统能控性与能观性的必要条件, 该判定条件只依赖于系统矩阵A(t)和输入矩阵B(t), 不必计算系统的系统状态转移矩阵, 使得判别时变系统能控性与能观性易于实现. 说明了本文结论是线性定常系统相应结论的自然扩展. 对进一步深入研究时变系统和时变广义系统具有实际启发作用.     

复杂动态网络环境下控制理论遇到的问题与挑战

以漫谈的方式讨论复杂动态网络环境下传统控制理论所遇到的一些新问题与新挑战. 具体地, 本文首先介绍现代网络科学与工程的背景, 然后讨论复杂动态网络的牵制控制、有向复杂网络的能控性以及"网络的网络"的 建模与控制等三个方面的相关科学研究问题.     

群体智能中的知识涌现与复杂适应性问题综述研究

阐述了群体智能的相关概念，分析了群体智能中的自恢复、间接通信和进化学习等特点;对群体智能中的知识涌现现象进行了研究，对智能的本质问题进行了探讨．将群体智能系统与复杂适应性系统进行了联系和对比，提出了群体系统是一种复杂适应性系统的观点．介绍了几个典型的实验模型．最后，在总结群体智能局限性的基础上，提出了系统智能的观点，并对群体智能的意义和发展趋势进行了简单的总结．     

高校机房管理中的若干问题的探索与研究

随着信息化技术的迅速发展,计算机已经应用到各大高校。计算机知识是大学生知识结构的重要组成部分,并且对计算机应用能力的要求也起来越高。高校计算机公共机房是学校计算机比较集中的地方,存在着学生流动量大,机器使用频率高、设备容易出问题、管理人员工作任务重等问题。结合我校计算机机房管理的具体实际,提出一些合理的建议来提高机房较高的使用率,进而使学生具有较高的动手使用计算机的能力,使计算机更好的为教学服务。     

数据挖掘在厦门大学研究生成绩系统中的研究与应用

针对目前厦门大学研究生成绩库中的数据没有得到有效利用的问题，本文提出对成绩库进行关联规则的挖掘。在不改变纵向成绩库结构的基础上，改进经典的Apriofi算法，即为侯选频繁项目集的每一个项目，逐遍扫描事务库：然后从减少扫描范围和改进sql语句两方面改善Apfiofi算法固有的缺陷，以大幅提高挖掘速度；最后利用管理学院的部分成绩库数据证明了关联规则在课程相关性分析上的有效性和实用性。     

公共政策过程中的政府自利性问题与对策研究

在公共政策的过程中,从某种意义上讲,政府自身利益的实现与社会公共利益的价值或多或少会存在内在的一致性,政府自利性行为的实现是在公共利益实现为前提的,合理范围内的政府自利性对公共利益的实现是有益的,同时也会起到一定的促进作用。但是,在寻求政府自利性行为的同时是以侵害或牺牲公共利益为代价的,则该行为必然会受到法律的制裁,这必然会影响社会公共利益的实现。通过分析政府自利性行为存在的原因,从完善公共政策的制度建设、建立相对合理的政府自身利益的结构机制和加强社会监督等方面提出了如何克服政府自利性行为。     

ADAMS/CAR与EASY5在车辆主动悬架动力学研究中的应用

概括介绍了ADAMS/CAR与EASY5仿真软件在车辆主动悬架研究中的应用,通过ADAMS/CAR建立了整车主动悬架的多体动力学模型,采用EASY5软件设计了主动悬架的液压系统,并提出了ADAMS/CAR与EASY5联合仿真的方案,对联合仿真技术应用于主动悬架进行了可行性分析.同时,车辆平顺性的仿真结果表明,采用液压主动悬架的车辆与采用被动悬架的车辆相比平顺性有了明显的改善.     

动态交通流建模及协调控制与优化策略

根据快速路交通流特性,建立主、辅路的动态交通流模型.根据不同的优化性能指标,确立相应的主、辅路协调优化策略,以便进一步开发实时控制算法进行优化控制.     

Unknown system dynamics estimator based coordinated control of the ultra supercritical boiler-turbine unit with coal pulverizing delay for large load accommodation

The ultra-supercritical boiler-turbine unit is required to accommodate large-range load following to maintain the stability of grid frequency. However, the input delay in the coal pulverizing process poses a challenge to the coordinated control of the boiler-turbine unit, which is always neglected in existing works but dramatically affects the stability of steam pressure and temperature. In this paper, to handle the delay caused by coal pulverizing, a predictor-based delay compensation structure is developed for producing a delay-free control framework for the throttle steam pressure. Moreover, to overcome intrinsic nonlinearities in the dynamics of the boiler-turbine unit, the unknown system dynamics estimator is employed in the controllers' design for the steam enthalpy in the separator and active power of the turbine. Thus, precise and fast regulation for the active power output can be achieved under wide load following task. The salient merit of the proposed control is that the overshot of the throttle steam pressure and the specific enthalpy in the separator can be significantly alleviated, which is necessary for turbine blade. A Lyapunov-Krasovskii functional is introduced to deal with the time delay in the stability proof. Finally, the proposed coordinated control is validated in three typical working scenarios.     

具有时滞的柔性关节多机械臂协同自适应位置/力控制

由于关节机械臂长期运行后,齿轮间隙扩大产生的时间滞后将使得系统跟踪性能降低.针对此问题,本文提出了一种自适应位置/力控制策略来保证闭环系统稳定性以及位置/力跟踪性能.首先,对多机械臂和物体系统进行任务空间动力学建模.随后,利用Pade理论将时间滞后近似为二阶有理分式.同时,利用神经网络自适应算法克服模型建模误差对系统稳定性的影响,利用同时包含位置误差和力误差的线性滑模项,设计位置/力控制器.通过李雅普诺夫稳定性理论,证明控制策略能实现位置误差和内力误差的渐近收敛.最后,仿真验证证明所设计控制策略的有效性.     

基于粒子群算法的交通干线协调控制的研究

目前各大城市交通拥堵的一个重要原因是交通控制仍然为单点控制,未能实现协调优化.基于此,提出一种基于粒子群优化的干线交通总延误最小协调控制方法.首先,通过对城市交通干线协调控制进行数学抽象,建立干线交通双向绿波控制总延误模型.其次,依据总延误模型的特征,设计了一种利用历史最优共享的粒子群算法(VSHBPSO).接着,对干线总延误模型进行优化,以总延误最小为目标,得出相位差、绿信比的最优解,进而获得交通信号相位的动态配时策略.最后以秦皇岛市交通干线为例进行仿真实验,实验结果表明,优化后的交叉口配时方案比传统的定时控制方案减少了43.1％的延误时间,有效提高了干线通行效率.     

网络控制系统的能控性和能观性

给出了网络控制系统的定义，并基于线性时不变系统的被控对象，建立了传感器为时钟驱动，控制器和作动器为事件驱动时长时滞网络控制系统的数学模型，对网络控制系统的均值能控、均方能控、均值能观及均方能观作了定义，得到了网络控制系统能控的充分或必要条件及能观的充要条件．     

多轴联动的风洞变角度机构同步协调控制

为解决风洞尾撑变角度机构运动过程中多轴之间的同步协调控制问题,本文提出了一种结合并行控制和交叉耦合控制的同步控制方法.首先,将并行控制应用于多轴联动控制中,根据前后侧滑轴定位时间一致以及速度变化时间一致的原则,开展了提高多轴同步性能的研究.然后,采用了基于同步误差传递函数的交叉耦合控制方法,对并行控制给定的运动参数进行修正补偿.最后,通过机构运动进行了实验验证,实验结果表明该控制方法可有效减小横向同步误差,提高同步性能,满足风洞试验控制要求.该方法也为类似机构的同步控制提供了参考.     

Adaptive coordinated control of engine speed and battery charging voltage

In this paper, the control problem of auxiliary power unit (APU) for hybrid electric vehicles is investigated.An adaptive controller is provided to achieve the coordinated control between the engine speed and the battery charging voltage. The proposed adaptive coordinated control laws for the throttle angle of the engine and the voltage of the powerconverter can guarantee not only the asymptotic tracking performance of the engine speed and the regulation of the battery charging voltage, but also the robust stability of the closed loop system under external load changes. Simulation results are given to verify the performance of the proposed adaptive controller.     

Adaptive coordinated control of engine speed and battery charging voltage

In this paper, the control problem of auxiliary power unit （APU） for hybrid electric vehicles is investigated. An adaptive controller is provided to achieve the coordinated control between the engine speed and the battery charging voltage. The proposed adaptive coordinated control laws for the throttle angle of the engine and the voltage of the power-converter can guarantee not only the asymptotic tracking performance of the engine speed and the regulation of the battery charging voltage, but also the robust stability of the closed loop system under external load changes. Simulation results are given to verify the performance of the proposed adaptive controller.     

Experiments in the coordinated control of an underwater arm/vehicle system

The addition of manipulators to small autonomous underwater vehicles (AUVs) can pose significant control challenges due to hydrodynamic interactions between the arm and the vehicle. Experiments conducted at the Monterey Bay Aquarium Research Institute (MBARI) using the OTTER vehicle have shown that dynamical interactions between an arm and a vehicle can be very significant. For the experiments reported in this paper, a single-link arm was mounted on OTTER. Tests showed that for 90-degree, two-second repetitive slews of the arm, the vehicle would move as much as 18 degrees in roll and 14 degrees in yaw when no vehicle control was applied.Using a new, highly accurate model of the arm/vehicle hydrodynamic interaction forces, which was developed as part of this research, a coordinated arm/vehicle control strategy was implemented. Under this model-based approach, interaction forces acting on the vehicle due to arm motion were predicted and fed into the vehicle controller. Using this method, station-keeping capability was greatly enhanced. Errors at the manipulator end point were reduced by over a factor of six when compared to results when no control was applied to the vehicle and by a factor of 2.5 when compared to results from a standard independent arm and vehicle feedback control approach. Using the coordinated-control strategy, arm end-point settling times were reduced by a factor three when compared to those obtained with arm and vehicle feedback control alone. These dramatic performance improvements were obtained with only a five-percent increase in total applied thrust.     

Controllability of multi-agent systems with time-delay in state and switching topology

In this article, the controllability issue is addressed for an interconnected system of multiple agents. The network associated with the system is of the leader–follower structure with some agents taking leader role and others being followers interconnected via the neighbour-based rule. Sufficient conditions are derived for the controllability of multi-agent systems with time-delay in state, as well as a graph-based uncontrollability topology structure is revealed. Both single and double integrator dynamics are considered. For switching topology, two algebraic necessary and sufficient conditions are derived for the controllability of multi-agent systems. Several examples are also presented to illustrate how to control the system to shape into the desired configurations.