This paper addresses the problem of root cause analysis (RCA) of actuator fault. By considering an actuator as an individual dynamic subsystem connected with process dynamic subsystem in cascade, an interconnected system is then constituted. The fault detection and diagnosis (FDD) algorithm is carried out in actuator subsystem and aims at identifying the root causes of actuator faults. According to real plant, outputs of the actuator subsystem are assumed inaccessible and are reconstructed by measurements of the global system, thus providing a means of monitoring and diagnosis of the plant at both local and global level. A condition of invertibility of the interconnected system is first developed to guarantee that faults occurring in the actuator subsystem will affect the measured output of the global system distinguishably. For that, a necessary and sufficient condition is proposed to ensure invertibility of the interconnected system. Effectiveness of the proposed approach is demonstrated on an intensified HEX reactor.
With the wide range of applications of the Internet and the rapid development of the communication technology, GPRS technology with its always-online, high access speed, high transfer rate and data traffic accounting, quickly becomes a hot research field of sensor networks connected to the Internet and exchanged the data. This paper based on technologies above, with the design of the GPRS module and the management system of a wireless meter reading system for background, makes a research on the date transmission, the transmission format and the transmission method using the GPRS DTU (Data Terminal Unit) in sensor networks. Then, we design a novel remote GPRS heat meter reading system. This system can realize the coordinated and unified management, remote control of dispersed households heat meter in the city. Finally, the interoperability of sensor networks and the Internet are achieved.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.