ABSTRACT
In May 2006, a group of researchers from the University of California, Berkeley, installed a wireless sensor network on the main-span and a tower of the Golden Gate Bridge, which consisted of 256 accelerometers. After the initial installation phase, the network operated on the bridge from June to September 2006, periodically collecting acceleration and temperature data and transmitting them to a base-station located inside the south tower. During this period, at least three earthquakes occurred in Northern California, the Glen Ellen shaking of magnitude 4.4 on August 2, 2006 being the largest amongst them. The sensor network on the bridge did not collect data during any of these earthquakes because it was not alert for their arrival: the network was either asleep or transmitting ambient vibration data collected prior to the arrival of the earthquake. Therefore it is crucial to design the earthquake monitoring system to support prioritized and preemptive task scheduling in sensing and communication.
