克服监控系统的缺点与局限中英文对照.docVIP

To overcome those disadvantages and limitations of monitoring systems, the wireless-based monitoring systems, which are based on small wireless vibration sensors and RF (Radio Frequency)- MEMS (MicroElectroMechanical System), have been developed. This paper describes the background of the system development and the applications to tunnel monitoring and provides a framework of the process for monitoring, manipulating, and transferring field data using the new developed systems. 2. RESEARCH RESULT OF MEMS BASED SENSING TECHNOLOGY IN THE CONSTRUCTION INDUSTRY 2.1 BiAST Sensor for measuring the strain rate of tracks BiAST (Biaxial Strain Transducer) is a MEMS-based two-way strain sensor that was developed by the Seamans Center of the University of Iowa. The sensor was developed for the purpose of estimating the fatigue life of rail structures by attaching the MEMS-based strain gauge on a track. An improved model from the UAST (Uniaxial Strain Transducer) prototype, which was developed as a one-way strain sensor, the BiAST sensor can be used for track structures that load weight in various ways or that change continuously. BiAST was also developed in order to improve the conventional metal foil- type strain gauge. The metal foil-type strain gauge has benefits such as cheaper price and ease of installment, but it also has barriers such as weak durability in outdoor environments, unstable linearity of signal, and measured values that change in the time lapse, so it is mainly used to measure dynamic strain for a short time. Therefore, it is expected that the MEMS-based strain sensor will solve the problems of conventional foil-type strain gauges (M. Obadat, 2003). 2.2 Wireless piezoelectric vibration sensor for structure monitoring The piezoelectric vibration sensor was developed at Stanford University to provide decent performance at a high frequency for structures. To verify the initial vibration of a structure, it adopted the latest structural moni