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1.
In the network environment, the single time-triggered scheme wastes limited bandwidth resources due to all the sampled data are transmitted to the networks, and the single event-triggered scheme may increase system error because of ignoring factors such as changes in network utilization. To reduce the design conservatism, this paper is concerned with the hybrid-triggered L1 fault detection filter design for a class of nonlinear networked control systems (NCSs) described by Takagi–Sugeno (T-S) fuzzy model. Taking the effects of time-triggered scheme and event-triggered scheme into consideration simultaneously, we construct a fuzzy fault detection system. New results on stability and L1 performance are proposed for fuzzy fault detection system by exploiting the Lyapunov–Krasovskii functional and by means of the integral inequality method. Specially, attention is focused on the design of fault detection filter that guarantees a prescribed L1 noise attenuation level . Finally, two examples are presented to demonstrate the effectiveness of the proposed method.  相似文献   
2.
我国煤炭检测方法标准化现状及其发展   总被引:2,自引:0,他引:2  
介绍了我国煤炭检测方法标准的发展与宣贯实施,分析了我国煤炭检测方法标准化工作的现状,探讨了煤炭检测方法标准化的发展与展望.  相似文献   
3.
在对比分析目前提升机制动系统的各种测试方法基础上,提出采用单片机和PC机组成的两级计算机系统测试方法来实现参数的检测和显示。着重介绍该系统的主要功能、硬件组成及软件设计思想。  相似文献   
4.
高建民 《山西建筑》2005,31(9):99-100
阐述了SMC隔墙板组成材料及主要技术性能指标,介绍了SMC轻质内隔墙板在工程中的工艺流程及安装要点,提出具体的质量要求,指出SMC隔墙板质轻、隔音、性能稳定,有广泛的应用前景。  相似文献   
5.
王建民  李辉  陈龙珠 《工业建筑》2005,35(11):47-49,46
以平面框架为例,通过分析结构的横向柔度,深入研究了局部构件损伤对框架水平位移变化的影响机理特征。基于上述工作,利用框架的层间相对水平位移变化量(RDCSF)作为损伤特征参数,结合神经网络设计,对结构进行损伤检测分析。  相似文献   
6.
The objective of this paper is to introduce a reference model of BACnet-based fire detection and monitoring system using MS/TP and ARCNET protocols. The reference model is designed to satisfy the requirements of response time, survivability and flexibility. The reference model is operated on the basis of BACnet, a standard communication protocol for building automation systems. In this study, a simulator for the reference model of fire detection and monitoring system was developed. Using the simulator, this study examined the validity of the reference model proposed in this study. This study also evaluated the performance of the BACnet-based fire detection and monitoring system in terms of network-induced delay. Simulation results show that the reference model satisfies the requirements of fire detection and monitoring system.  相似文献   
7.
Eullaffroy P  Vernet G 《Water research》2003,37(9):1983-1990
The use of herbicides constitutes the principal method of weed control but the introduction of these compounds into the aquatic environment (primarily through runoff) may have severe consequences for non-target plants. In this study, we describe a sensitive and inexpensive method for detection of photosynthesis-inhibiting herbicides, based on chlorophyll (Chl) fluorescence emission. Algae exhibited a Chl fluorescence signature with two maxima around 684 and 735 nm, correlated with the total Chl content of the algal suspension. The ratio of these two maxima (i.e. F684/F735) can be used as an indicator of stress in the photosynthetic apparatus, and thus represents a very simple method for in vivo evaluation of the health status of algae. Determination of the F684/F735 fluorescence ratio revealed the presence and phytotoxicity of atrazine, metribuzin, terbuthylazine, diuron, DCPMU, DCPU and paraquat. The toxic effect of these pollutants was estimated by monitoring the increase in the F684/F735 value, which reflects photosystem II and photosystem I photochemistry. We observed a drastic increase in the magnitude of this ratio, correlating quantitatively with herbicide concentration and corresponding to a decline in algal photosynthetic activity. For the tested herbicides affecting photosynthetic electron transport, the magnitude of the effect was as follows: diuron= DCPMU > metribuzin > atrazine > terbuthylazine > paraquat > DCPU. The F684/F735 Chl fluorescence ratio thus gives toxicity responses which compare favourably with tests such as the algal growth inhibition test, and could therefore be used to detect the presence and phytotoxicity of herbicides in aquatic environments.  相似文献   
8.
防火墙集成系统包括操作、集中管理控制、入侵检测三部分.其操作模块又含规则处理、规则库、智能分析、防火墙插件、决策、告警等模块.入侵检测模块则由发送、处理、检测器输送、检测器等规则模块组成.集中管理控制模块负责对防火墙操作、入侵检测模块进行图形界面管理,并对其配置、启动等方面加以控制.  相似文献   
9.
This paper presents a contingency screening method and a framework for its on-line implementation. The proposed method carries out contingency screening and on-line stability assessment with respect to first-swing transient stability. For that purpose, it utilizes the single machine equivalent method and aims at improving the prior developed contingency screening approaches. In order to determine vulnerability of the system with respect to a particular contingency, only one time-domain simulation needs to be performed. An early stop criteria is proposed so that in a majority of the cases the simulation can be terminated after a few hundred milliseconds of simulated system response. The method’s outcome is an assessment of the system’s stability and a classification of each considered contingency. The contingencies are categorized by exploiting parameters of an equivalent one machine infinite bus system. A novel island detection approach, appropriate for an on-line application since it utilizes efficient algorithms from graph theory and enables stability assessment of individual islands, is also introduced. The New England and New York system as well as the large-scale model of the Continental-European interconnected system are used to test the proposed method with respect to assessment accuracy and computation time.  相似文献   
10.
该文针对目前高速公路工程试验检测管理工程的现状进行分析,然后以某高速公路工程为例,详细分析如何做好高速公路工程试验检测管理工作。  相似文献   
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