Comparison of Signal-Analysis Techniques for Seismic Detection System for High-Speed Train Data: Effect of Bridge Structures

Abstract

This study evaluated the earthquake warning system for high-speed trains using onboard accelerometers instead of expensive seismometers. Onboard accelerometers measure the train data additional to the earthquake acceleration. The measured earthquake acceleration could also be modified by railroad-supporting bridges. To develop the data analysis system, the virtual onboard data sets are synthesized using the train acceleration data and earthquake data. Not only the earthquake acceleration data but also the earthquake responses of bridges are used for the virtual onboard data synthesis. For the analysis of synthesized data, the short-time Fourier Transform (STFT), the wavelet transform (WT), and Wigner–Ville Distribution (WVD) methods have been compared. Results show that WVD provides the best detection performance while the computational costs are large.

Inspection of intermodular connection locations for multistory modular buildings

“…Such devices have been extensively used in studies on structural health monitoring, autopilot, environment monitoring, etc. [54][55][56][57] TF mini plus and U81 are laser distance sensors that can be connected to a Raspberry Pi; their specifications are summarized in Table 1. The accuracy and maximum range of the TF mini plus are 10 mm and 12 m, respectively, which do not meet the previously discussed requirements for this study.…”