搜索三个不同坏硬币的测试次数

§1.简介 设S={c_1,c_2,…,c_n}是由n个外观相同的硬币组成的集合,其中恰有m个稍重的坏硬币,试用最少的测试次数找出这m个坏硬币.以μ_m(n)表示最少测试次数,由信息论可知     

浅析广告创意产生的过程

文章将广告创意的产生分为准备、分析、顿悟和评估四个阶段,针对每个阶段的工作重点、工作方法进行阐述,涉及到多种思维方式和创意技巧,旨在说明创意不能仅靠天赋,更应源于科学的方法和步骤。     

基于反步自适应神经网络的船舶航迹控制

针对欠驱动船舶在稳定航速条件下轨迹跟踪问题,提出了一种基于自适应神经网络与反步法相结合的控制算法.该算法将实际的欠驱动船舶视为模型完全未知的非线性系统,利用神经网络的函数逼近特性实现控制器中非线性部分的在线估计,采用同时调整输入层-隐层、隐层-输出层间的权值阵的方法进行神经网络权值调整.通过选取积分型Lyapunov函数证明了闭环系统的稳定性.仿真实验表明该控制策略具有良好的跟踪特性,可以实现对期望航迹的精确跟踪.     

紧扣内存变量关系巧解矩阵类问题

C语言学习过程中,不少初学者不能建立思维的模型,无法将形象可行的矩阵运算、旋转事件抽象化成算法语言。讲解了指导学生掌握矩阵操作算法的推导方法。     

On the backstepping design procedure for multiple input nonlinear systems

In a recent paper, we developed a structural decomposition for multiple input multiple output nonlinear systems that are affine in control but otherwise general. In this paper, we exploit the structural properties of such a decomposition in the application of the backstepping design technique on multiple input nonlinear systems. In particular, this decomposition simplifies the conventional backstepping design and motivates new backstepping design procedures that are able to stabilize systems on which the conventional backstepping procedure is not applicable. Copyright © 2011 John Wiley & Sons, Ltd.     

Integrated relative position and attitude control of spacecraft in proximity operation missions

This paper addresses an integrated relative position and attitude control strategy for a pursuer spacecraft flying to a space target in proximity operation missions. Relative translation and rotation dynamics are both presented, and further integratedly considered due to mutual couplings, which results in a six degrees-of-freedom (6-DOF) control system. In order to simultaneously achieve relative position and attitude requirements, an adaptive backstepping control law is designed, where a command filter is introduced to overcome "explosion of terms". Within the Lyapunov framework, the proposed controller is proved to ensure the ultimate boundedness of relative position and attitude signals, in the presence of external disturbances and unknown system parameters. Numerical simulation demonstrates the effect of the designed control law.     

Design of a two‐level controller for an active suspension system

The paper focuses on a control design for a vehicle suspension system in which a balance between different performance demands is achieved. The starting point of the control design is a full–car model which contains nonlinear components, i.e. the dynamics of the dampers and springs and nonlinear actuator dynamics. In order to handle the high complexity of the problem this paper proposes the design of a two‐level controller of an active suspension system. The required control force is computed by applying a high‐level controller, which is designed using a linear parameter varying (LPV) method. For the control design the model is augmented with weighting functions specified by the performance demands and the uncertainty assumptions. The actuator generating the necessary control force is modelled as a nonlinear system for which a low‐level force‐tracking controller is designed. To obtain the low‐level controller a backstepping method is proposed. As an alternative solution a feedback linearization method is also presented. The operation of the controller is illustrated through simulation examples. Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society     

SPECTRAL RADIUS,KRONECKER PRODUCTS AND STATIONARITY

Abstract. We provide a stochastic proof of the inequality ρ(A?A+B?B) ≥ρ(A?A), where ρ(M) denotes the spectral radius of any square matrix M, i.e. max{|eigenvalues| of M}, and M?N denotes the Kronecker product of any two matrices M and N. The inequality is then used to show that stationarity of the bilinear model will imply stationarity of the linear part, i.e. the linear ARMA model for r= 1 and q= 1. Furthermore, it is shown that stationarity of the subdiagonal model, i.e. the bilinear model with b_ij=0 for i< j, again implies stationarity of its linear part, provided that the stationarity condition given by Bhaskara Rao and his colleagues is met. Interestingly, the conclusion that stationarity of the subdiagonal models, implies that the linear component models cannot be extended to the general non-subdiagonal bilinear models. The last observation is demonstrated via a simple example with p=m= 1, r= 0 and q= 2.     

火车车轮成形新工艺的开发研究

在比较分析技术先进国家的火车车轮成形工艺流程后，采用试验研究和数值模拟相结合方法，研究开发出优化的新工艺。钢坯先在一台水压机上预成形制坯，再在另一台压机上模锻，经轧制扩径后冲孔压弯。这样的生产线效益最好     

医院门诊就诊流程优化研究

以业务流程再造、程序分析等相关理论方法为基础,以J市R医院消化内科为例,对医院门诊就诊流程进行优化研究。通过实地走访与问卷调查发现消化内科现行门诊服务流程中存在的问题,基于业务流程再造理论优化门诊服务流程,使用程序分析方法和Flexsim仿真对门诊就诊流程进行对比分析,验证了优化方案的有效性。