具有执行器故障的Delta算子系统D稳定H_∞鲁棒容错控制

研究Delta算子描述的不确定线性系统在区域极点约束和H∞范数界约束下的鲁棒容错控制问题。利用线性矩阵不等式（LMI）理论,给出了在执行器失效情况下Delta算子不确定系统在区域极点约束下的鲁棒H∞容错控制存在的充分条件,并可通过求解LMI得到鲁棒容错控制器的设计。所得结果可将连续系统和离散系统的有关结果统一到Delta算子框架中。数值算例验证了该方法的可行性。     

Delta算子不确定系统的多目标鲁棒 H∞控制

研究Delta算子描述的线性不确定离散系统在区域极点配置约束下的鲁棒H∞控制问题。目的是设计状态反馈控制器，使得闭环极点位于预先指定的圆形区域，且闭环系统传递函数的H∞范数小于给定的正常数。基于Delta算子系统具有H∞范数界二次D可镇定的概念，导出状态矩阵和输入矩阵均存在不确定性时，Delta算子系统具有H∞范数界的鲁棒区域极点配置的充要条件及其状态反馈设计。研究结果表明，可将现有结果推广到更为一般的情形，并可统一处理连续与离散系统的相关问题。     

具有区域极点和方差约束的Delta 算子 系统鲁棒H ∞滤波

研究Delta算子不确定系统在误差方差约束和区域极点约束下的鲁棒H∞滤波问题，针对多目标H∞滤波问题，采用代数矩阵不等式方法，提出滤波器的存在条件和显式表达式．所得结果可将连续系统和离散系统的有关结果统一到Delta算子框架。     

Delta算子系统的鲁棒性能分析

1　引　言线性连续和离散系统的鲁棒分析包括稳定鲁棒性与性能鲁棒性 ,主要方法有特征值分析、Lyapunov理论和矩阵测度方法 ,现已取得较大进展 .但现有结果未能建立连续和离散系统鲁棒性能之间的直接联系 .Delta算子是一种统一的描述形式 ,可以将连续和离散系统的许多结果纳入 Delta算子系统的统一框架 [1 ] .Piou[2 ] 基于模态分解法和 Gron-wall引理得到 Delta统一模型稳定鲁棒的充分条件 .本文将文 [3]的结果推广到 D域稳定情形 ,利用矩阵测度方法给出了 Delta算子系统鲁棒 D稳定的充分条件 ,所得结论同时适用于连续和离散系统 .文中…     

Delta算子系统的状态反馈鲁棒镇定与鲁棒H∞控制

研究Delta算子描述的线性不确定离散系统的鲁棒镇定与H∞控制问题,提出了“Delta算子系统二次稳定与二次可镇定”的概念,推导出Delta算子不确定系统鲁棒二次可镇定的充要条件及其状态反馈控制律,基于Delta算子界实引理,给出闭环不确定系统具有H∞范数界的充分条件和状态反馈设计,所得结论将连续与离散系统的有关结果统一于Delta算子框架。     

Delta算子系统具有极点约束的鲁棒非脆弱方差控制

研究Delta算子描述的线性不确定系统具有圆形区域极点约束的鲁棒非脆弱方差控制问题. 针对系统参数范数有界不确定性和控制器的乘性增益不确定性, 运用线性矩阵不等式(LMI)方法, 提出具有圆形区域极点约束的状态反馈鲁棒非脆弱方差控制器存在的条件和设计方法. 数值算例表明设计方法的可行性.     

Delta算子时滞系统的可靠D--镇定

研究同时含有执行器故障和传感器故障的Delta算子时滞系统的鲁棒可靠D-镇定问题.利用矩阵特征值理论和线性矩阵不等式方法,给出了Delta算子时滞系统D-稳定的充分条件,进而,针对同时含有执行器故障和传感器故障的Delta算子范数有界参数不确定时滞系统,设计鲁棒可靠D-镇定状态反馈控制器,使得对于所有容许的不确定性、执行器故障和传感器故障,Delta算子闭环时滞系统的极点均落在复平面指定圆盘区域内.最后,通过数值算例验证了控制器设计方法的可行性和有效性.     

Delta算子系统具有圆形区域极点约束的非脆弱H∞滤波器设计: 一种LMI优化方法

研究了一类Delta算子线性系统具有圆形区域极点配置的非脆弱 H∞滤波器设计问题. 本文的目的是设计滤波器使得滤波误差系统不仅满足给定的圆点极点约束或D稳定约束, 而且从扰动输入到滤波误差的传递函数满足给定的 H∞范数约束. 所设计的滤波器具有乘性的滤波器增益变化, 基于Lyapunov稳定性理论和线性矩阵不等式方法, 给出具有区域极点配置的Delta算子离散系统非脆弱 H∞滤波器存在的充分条件. 数值仿真例子说明设计方法的有效性以及所提设计方法具有更小的保守性.     

区间Delta算子系统的鲁棒性分析与控制

研究Delta算子描述的区间系统的鲁棒稳定分析与鲁棒综合设计问题，在给出区间系统的一种等价描述后，利用Delta域的Lyapunov稳定性理论，提出了区间Delta算子系统鲁棒稳定的充分条件及状态反馈控制设计方法，所得结论可以将连续区间系统与离散区间系统的有关结果纳入到Delta算子系统的统一框架中。     

传感器有故障的Delta算子线性不确定系统的鲁棒D–稳定

研究传感器有故障的Delta算子线性不确定系统的鲁棒D–稳定问题, 旨在设计控制器以消除系统不确定性和传感器故障的影响, 确保闭环系统极点落在复平面指定圆盘区域内. 由于传感器故障具有连续的故障模型, 本文采用线性矩阵不等式(LMI)方法, 利用故障模型的结构信息, 得出了Delta算子系统状态反馈鲁棒D–稳定控制器存在的充分条件, 并由此提出相应控制器设计方法. 数值算例表明设计方法的可行性和有效性.     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate