Yoshihisa Shimizu

Real-Time City Gas Network Damage Estimation System: SIGNAL

SIGNAL’S main functions include the rapid monitoring, using a reliable radio network, of: SI and seismic acceleration at 331 locations, acceleration waves at 5 locations, and rising ground water levels at 20 locations considered most at risk from ground liquefaction. This real-time earthquake data is linked to GIS data bases of gas pipelines and ground conditions, to give an accurate damage estimation based on records of pipe damage suffered in previous earthquakes. The estimation of damage to the gas network is useful for the rapid implementation of emergency work, and in drawing up efficient and accurate restoration plans.

Innovative spectral intensity transducer using three-axial micromachining accelerometer for earthquake crisis management

A new generation spectrum intensity (SI) transducer has been developed utilizing micromachining three-axial accelerometer and a newly developed SI calculation algorithm for earthquake damage detection. The new SI transducer will be placed at 3600 sites around Tokyo Bay for monitoring earthquake damage of the area. Comparison with an existing servo type SI transducer proved a very good match in detecting simulated actual earthquake waveforms. This new transducer can even detect the liquefaction level of the ground caused by an earthquake. An innovative approach for the realization of this small sized, low cost and highly accurate SI transducer is presented.