News

The following news item was contributed by the High Performance Wireless Research and Education Network (HPWREN) project, a joint effort of SDSC and the Scripps Institution of Oceanography (both organized research units of the University of California, San Diego). HPWREN is creating, demonstrating, and evaluating a non-commercial prototype of a high-performance, wide-area wireless network in San Diego county. This NSF-funded network includes backbone nodes on the UC San Diego campus and a number of "hard to reach" areas in San Diego county; it not only is used for network analysis research, but also provides high-speed Internet access to field researchers from several disciplines (geophysics, astronomy, ecology) and educational opportunities for rural Native American learning centers and schools. See http://hpwren.ucsd.edu/ for more information.

With two Network for Earthquake Engineering Simulation ( NEES) project sites now connected to HPWREN, scientists from around the world are able to send and receive even more near-real-time seismic data collected in southern California. [Image]

The Garner Valley Downhole Array ( GVDA) site is one of the southern California NEES projects that currently utilizes HPWREN connectivity. Specifically, the GVDA uses a borehole array and a surface array to measure ground motion via sensors that are located as deep as 500 meters below the Earth's surface.

"By comparing data collected by the HPWREN-connected borehole sensors with additional seismic records, we can calibrate and improve our existing physical models for wave propagation in the Earth," explained GVDA principal investigator Jamison Steidl of the Institute for Crustal Studies, University of California at Santa Barbara. "This, in turn, allows us to improve our understanding of the behavior of soils under different levels of ground shaking."

The additional NEES project that recently linked to HPWREN is the Powell Laboratories/Camp Elliott site, which will soon be home to the world's first outdoor shake table and the largest shake table in the United States.

Similar to GVDA scientists, Camp Elliott researchers will utilize HPWREN connectivity to transmit near-real-time seismic activity from the 25-foot by 40-foot shake table to desktops throughout the world.

Once complete, the Powell Laboratories/Camp Elliott large high-performance shake table will be connected to HPWREN. This shake table will allow scientists to perform dynamic earthquake hazard mitigation tests on full-scale structural systems. (Image courtesy Powell Lab/Camp Elliot.)

"Because there is no roof over the shake table, we will be able to use tall cranes and heavy equipment to construct and test full-scale buildings and structures, which has not been possible before," said Lelli Van Den Einde, Project Manager of the UCSD-NEES Large High Performance Outdoor Shake Table project. "This will enable the development of new construction techniques as well as the validation of analytical computer models against test results we see in our laboratory experiments. Furthermore, the tele-presence connection through HPWREN will enable researchers from remote institutions to use the facility."

More information about the Garner Valley Downhole Array is available at http://www.crustal.ucsb.edu/observatories/gvda/.

More information about the Camp Elliott site is available at http://hpwren.ucsd.edu/news/020809.html, http://www.jacobsschool.ucsd.edu/Camp_Elliott/, and http://structures.ucsd.edu/NEES/.

Additional information about the NSF-funded NEES projects is available at http://www.eng.nsf.gov/nees/.