基于极限平衡理论的局部最小安全系数法

根据极限平衡原理和Mohr Coulomb破坏准则 ,应用最优控制理论思想 ,并充分考虑运动许可条件 ,建立了能同时确定边坡临界滑动面和计算最小安全系数的局部最小安全系数法。该法既满足条块力和力矩的平衡 ,又符合边坡稳定问题的物理本质 ;既能保证所求解是运动许可的 ,又能保证不出现数值计算上的困难 ;不但可以确定临界滑动面和计算对应的最小安全系数 ,又可以确定条底及条块界面上法向力的作用点 ,从而消除了以往利用极限平衡法进行边坡稳定分析时对临界滑动面的形状以及条底和条块界面上法向力的作用点的人为假定。算例计算比较表明 ,本文所给方法是合理可靠的。     

Decentralised H ∞ control for singular systems

In this article, considering the design problem of decentralised H _∞ controller of singular systems, the two cases of controllers via measurement feedback are designed: one is precise controller, and the other is additive controller gain variation. The design procedures of the two cases of controllers are presented in terms of the solutions to generalised algebraic Riccati inequalities. The designed controllers in each case guarantee that closed-loop singular systems are admissible and with H _∞-norm bound on disturbance attenuation. Finally, a numerical example to demonstrate the validity of the proposed approach is given.     

Robust non‐fragile control for delayed singular Markovian jump systems with actuator saturation and partially unknown transition probabilities

The paper is devoted to the investigation of the problem of robust non‐fragile control for singular Markovian jump systems with time‐varying delay and saturating actuators under partially unknown transition probabilities. By employing a Lyapunow function, a mode‐dependent robust non‐fragile state feedback controller, as well as an estimate of the domain of attraction in the mean square sense, is derived to guarantee stochastic admissibility of the corresponding closed‐loop system with actuator saturation. The controller parameters can be obtained by solving a series of linear matrix inequalities. An illustrative example is provided to show the effectiveness of the proposed method. Copyright © 2016 John Wiley & Sons, Ltd.     

具有随机移走逐步增加Ⅱ型截尾下Burr-Ⅻ分布的可靠性估计

在具有随机移走逐步增加Ⅱ型截尾下,讨论了Burr-Ⅻ分布的可靠性估计及其性质。选取共轭先验分布,基于刻度平方误差损失函数,同时随机移走部件数服从二项分布,给出了Burr-Ⅻ分布参数、随机移走概率、可靠度函数及失效率的Bayes估计,并证明了形如[cT+d]-1的一类估计的容许性。最后运用Monte Carlo方法对各种估计结果的均方误差进行了模拟比较。结果表明,在随机移走概率p=0.4处进行试验,估计结果的精度高。     

Novel admissibility and robust stabilization conditions for fractional-order singular systems with polytopic uncertainties

This paper considers the issues of the admissibility and robust stabilization of fractional-order singular systems with polytopic uncertainties and fractional-order and . Firstly, the novel admissibility conditions for nominal fractional-order singular systems are proposed with no conservatism and without any equalities or nonstrict inequalities. Secondly, the robust admissibility conditions for fractional-order singular systems with polytopic uncertainties are given based on the admissibility conditions for nominal fractional-order singular systems. Thirdly, to make the uncertain fractional-order singular systems robustly admissible, the methods of designing the static output feedback controllers are obtained with wider application scope, which are direct, concise, and more relaxed compared with the existing results. All the results are proposed in terms of linear matrix inequalities. Finally, three illustrative examples are given to demonstrate the effectiveness of the results.     

基于尺度能量参数的子波变换及其应用

提出基于尺度能量参数的子波变换方法。首先给出了尺度能量参数的概念,讨论基于这一参数的子波变换的时频特性,然后推导基于尺度能量参数的子波变换的逆变换,给出并证明其容许性条件成立的充分条件。文中给出基于尺度能量参数的子波变换中尺度与波长的关系,并且分析了一组黄河上游年径流量数据。研究结果表明,基于尺度能量参数的子波变换能够放大、突出不同尺度下的信号特征。     

一类刻度指数分布族参数的Bayes估计

在刻度平方损失函数下,研究了一类刻度指数分布族参数的估计.得到了刻度参数的Bayes估计的一般形式,并研究了它的可容许性,最后在两种给定先验分布下得到了刻度参数的正常Bayes估计和广义Bayes估计的精确形式.在此基础上可以对刻度参数进行进一步的统计推断.     

核电厂总体规划需要考虑的因素简析

总体规划是核电厂一项重要的设计工作,需要考虑的因素较复杂,且综合性很强。文章从安全可靠性、环境相容性、技术可行性和经济合理性4个方面入手,对需要考虑的因素进行了简要分析,以期对核电厂总体规划有所帮助。