Controlling uncertain fuzzy neutral dynamic systems with Markov jumps

The robust H∞ control problems for stochastic fuzzy neutral Markov jump systems (MJSs) with parameters uncertainties and multiple time-delays are considered. The delays are respectively considered as constant and time varying, and the uncertain parameters are assumed to be norm bounded. By means of Takagi-Sugeno fuzzy models, the overall closed-loop fuzzy dynamics are constructed through selected membership functions. By selecting the appropriate Lyapunov-Krasovskii functions, the sufficient condition is given such that the uncertain fuzzy neutral MJSs are stochastically stability for all admissible uncertainties and satisfies the given H∞ control index. The stability and H∞ control criteria are formulated in the form of linear matrix inequalities, which can be easily checked in practice. Practical examples illustrate the effectiveness of the developed techniques.     

Coordination-theoretic approach to modelling grid service composition process

A grid service composite process is made up of complex coordinative activities. Developing the appropriate model of grid service coordinative activities is an important foundation for the grid service composition. According to the coordination theory, this paper elaborates the process of the grid service composition by using UML 2.0, and proposes an approach to modelling the grid service composition process based on the coordination theory. This approach helps not only to analyze accurately the task activities and relevant dependencies among task activities, but also to facilitate the adaptability of the grid service orchestration to further realize the connectivity, timeliness, appropriateness and expansibility of the grid service composition.     

Robust H∞ guaranteed cost satisfactory fault-tolerant control for discrete-time systems with quadratic D stabilizability

The problem of robust H∞ guaranteed cost satisfactory fault-tolerant control with quadratic D stabilizability against actuator failures is investigated for a class of discrete-time systems with value-bounded uncertainties existing in both the state and control input matrices. Based on a more practical and general model of actuator continuous gain failures, taking the transient property, robust behaviour on H∞ performance and quadratic cost performance requirements into consideration, sufficient conditions for the existence of satisfactory fault-tolerant controller are given and the effective design steps with constraints of multiple performance indices are provided. Meanwhile, the consistency of the regional pole index, H∞ norm-bound constraint and cost performance indices is set up for fault-tolerant control. A simulation example shows the effectiveness of the proposed method.     

Pulsar/CNS integrated navigation based on federated UKF

In order to improve the autonomous navigation capability of satellite, a pulsar/CNS (celestial navigation system) integrated navigation method based on federated unscented Kalman filter (UKF) is proposed. The celestial navigation is a mature and stable navigation method. However, its position determination performance is not satisfied due to the low accuracy of horizon sensor. Single pulsar navigation is a new navigation method, which can provide highly accurate range measurements. The major drawback of single pulsar navigation is that the system is completely unobservable. As two methods are complementary to each other, the federated UKF is used here for fusing the navigation data from single pulsar navigation and CNS. Compared to the traditional celestial navigation method and single pulsar navigation, the integrated navigation method can provide better navigation performance. The simulation results demonstrate the feasibility and effectiveness of the navigation method.     

论浅埋隧道围岩压力的确定

浅埋隧道埋深较浅的坑道.在坑道埋深不大时,会使整个覆盖层产生扰动,较易发生洞顶坍塌,有时会使地表开裂下陷,因此会产生较大的围岩压力,文章推算了用公式计算围岩的垂直压力.     

移峰填谷节约电费

抓好用电科学管理,合理调配使用电能,是投资少、见效快,实现节能的一条捷径.     

城市园林植物配置艺术研究

城市园林在改善生态环境,提高环境质量方面有着不可替代的作用.在园林设计中,植物配置占有重要地位,直接影响到园林工程质量及园林功能发挥.园林植物配置要遵循科学性,讲究艺术性,力求科学合理地配置.     

单个大气超细颗粒物源特征的同步辐射光源X射线探针初步研究

研究了单个大气超细颗粒分析靶样的制备方法, 在美国阿贡国家实验室APS同步光源的13-ID-C试验站, 用束斑为2 μm的X射线探针分析了不同污染源超细颗粒物, 得到了单个超细颗粒物的特征X射线谱. 实验结果表明, 来自不同污染源的超细单颗粒具有不同的特征X射线能谱. 这为单颗粒分析方法识别大气超细颗粒物来源提供了依据. 超细含铅颗粒物的分析暗示, 大气颗粒物中的铅污染是多源的, 除燃烧加铅汽油外, 燃煤和钢铁工业也是大气铅污染的排放源. 来自燃煤排放的超细颗粒分析提示, 燃煤超细颗粒物对人体健康具有更大的潜在危害.     

对中西医结合的一点反思

随着近代科学的形成、崛起并传人我国,中西学"汇通"成为潮流,深刻影响了我国整个学术领域的发展.19世纪以后,在一些医学家和官员的推动下,汇通中西医的思想在医药界也渐成气候,逐渐形成了中西医汇通学派.对现代中医学的发展产生了重大影响.新中国成立后中西医结合在我国得到了高度重视,其发展进入了快车道,并被赋予了结合中医中药与西医西药的知识及方法.在提高临床疗效的基础上,阐明机理进而创立"新医学"的定位.     

禹门口提水东扩工程二级泵站蝶阀加空气阀联合防护下水力过渡过程的数值模拟研究

随着供水距离的加大及电机制造工艺的进步,水泵机组越来越小型化、轻量化,压力管道的安全运行已经成为研究的重点。本研究通过建立水泵及空气阀边界的数学模型,基于计算机数值模拟以期优化蝶阀关闭并确定空气阀位置及数量,结合工程实例提出供水系统经济安全的运行制度。