Friday, April 11, 2008

Scientists links laptops to detect earthquakes

Elizabeth Cochran sensed an opportunity to save lives when she realized laptops can be used as seismometers to detect earthquakes.

Many laptops have an accelerometer, a sensor that detects motion and free fall, and that can be used to detect the intensity of earthquakes when a laptop shakes, said Cochran, a seismologist and assistant professor at the department of earth sciences at the University of California, Irvine.

Cochran, along with other scientists, is working on the Quake-Catcher Network (QCN), a project that harnesses seismic data from sensors on Internet-connected laptops in different locations to help capture earthquakes. When the laptop isn't being used, special software on laptops collects sensor data, which along with the laptop's location, is sent over the Internet to an earthquake data repository where the data is analyzed.

Amassing sensor data from thousands of Internet-connected laptops could determine an earthquake's intensity and its exact location, which could be helpful for first responders in relief efforts, Cochran said. It could also help examine quake trends over time at different locations.

The goal is to create a dense seismic network for scientific study and to measure how shaking gets concentrated, Cochran said. The data will also be a resource for first responders to identify the exact location of an earthquake for rapid relief. Currently the network has 300 people signed up, but Cochran hopes to sign up more participants in different locations.

"If you donate laptop time for your network, you will be donating to somebody 20 miles away from the network. They will help you back in the future," Cochran said.

The project will also fill the gap between seismic stations to check for earthquake activity, Cochran said. In Southern California there are 350 instruments collecting seismometers, but there is a significant distance between them and those gaps need to be filled, she said. The seismometers are expensive, so linking laptops is an inexpensive way to provide instant information on earthquakes in designated areas.

The client-based software used on laptops, called BOINC, is available as a free download on QCN'sWeb site. It works only with Mac OS systems but will soon be available for Windows, Cochran said.

The software isn't a burden on laptops -- it takes up small system resources and a small amount of hard drive space, Cochran said. "We use just a few percent of the processing capabilities of the laptop to read the sensor data and determine if the signal is outside of the norm," Cochran said.

The project is just starting off and working through small kinks to make the earthquake readings more accurate.

The software determines a laptop's location based on Internet Protocol (IP) addresses, but that isn't always accurate as the location and sensor readings may not match up. BOINC provides a Google interface where a user can specify the laptop's location, to which the IP address is then linked. "We know there will be some locations that are different from what the IP address suggests. From user response we hope to improve," Cochran said.

False alerts on an earthquake are also a possibility as laptops are constantly on shaking, but the network monitors the signal for a few minutes or days before acting on it, Cochran said.

In general, earthquakes are hard to predict, but Cochran hopes the data collected through the effort is reliable enough to make it an early warning system. Cochran and the scientists have also requested funding from the National Science Foundation to develop the QCN infrastructure as a scientific and education tool.

The client-side software used by QCN is the same as the software used by SETI (Search for Extraterrestrial Intelligence), another distributed computing effort that harnesses the power of thousands of computers searching for different life forms in the universe by analyzing radio telescope data. - nypost

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