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DAILY NEWS AND INFORMATION
FOR THE GLOBAL GRID COMMUNITY / SEPTEMBER 1, 2003; VOL. 2 NO. 35
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Applications:
NEESgrid A SEISMIC SHIFT FOR
EARTHQUAKE RESEARCH
The field of earthquake research is undergoing a seismic shift of its own
as
the developing NEESgrid changes the very idea of what constitutes a
laboratory.
When completed in 2004, the NEESgrid will link participants in the George
E.
Brown, Jr. Network for Earthquake Engineering Simulation (NEES) with leading-
edge computing resources and research equipment, allowing researchers to
collaborate on experiments and share tools. With NEESgrid's capabilities-
including data storage and management, teleobservation, and the ability to
capture information and control an experiment from a remote site-researchers
aren't constrained by geography; instead, they can collaborate in a virtual
laboratory or "collaboratory."
The development of NEESgrid is being led by the National Center for
Supercomputing Applications (NCSA) in collaboration with Argonne National
Laboratory, the University of Michigan, the University of Oklahoma, the
University of Southern California and USC/Information Science Institute.
"NEESgrid provides the technical infrastructure so earthquake engineering
researchers can think creatively and think beyond their own labs," said Dan
Abrams, a University of Illinois professor of civil and environmental
engineering, and Director of the Mid-American Earthquake Center.
Delivering The 'MOST'
The power of this virtual laboratory was on display in July during the
multi-
site online simulation test, or MOST. Spanning a thousand miles, MOST
connected earthquake researchers at the University of Illinois at Urbana-
Champaign and the University of Colorado at Boulder with the computational
power at NCSA. Together, the three sites conducted an experiment to examine
the effects of force on a one-story, two-bay frame, like one from the interior
of a multistory building.
One column of the structure, painted a school-spirited orange and blue, was
tested at the University of Illinois MUST-SIM (multi-axial full-scale sub-
structuring testing and simulation) facility; the test controller also was
based at the University of Illinois. A second column was simultaneously tested
at the University of Colorado Fast Hybrid Test facility. The remaining portion
of the structure existed only in the virtual world-it was simulated by NCSA's
computer systems.
The MOST experiment lasted far longer than a real-world quake. An actual
earthquake tremor lasts only seconds, but in order to study the forces at work
scientists break the event into discrete intervals. During each interval in
the MOST experiment, force data was fed to the computational model at NCSA;
the correct displacements were calculated and sent to the Illinois and
Colorado physical test sites; displacements were applied to the physical
models; and forces for the next iteration were measured and sent to the
computational model at NCSA. This cycle was repeated 1,500 hundred times
during MOST, which lasted for about five hours.
For MOST, the response of the structure was designed to stay within its
elastic range, allowing the team to work with a problem to which they already
knew the answer. In the future, NEESgrid will enable increasingly complex
experiments that will be used to better to understand how earthquakes damage
structures and how homes and businesses can be built to withstand an
earthquake's force.
A large number of graduate students from UIUC, Colorado and NCSA were
involved
in the test, which thus provided an advanced environment for training future
professionals.
Enabling Collaboration
To show off the NEESgrid's collaboration-enabling tools, anyone with a Web
browser was able to participate in the MOST experiment. From the MOST Web
site, anyone could receive a password and with it access to experimental data,
data plots and visualizations, streaming video from the test sites, real-time
chat about the experiment, threaded discussions and electronic lab
notebooks.
As the NEESgrid is adopted at all NEES equipment sites, researchers can use
the chat and discussion features to frame experiments on which to collaborate.
Collaborators can then create their own private workspaces in which they can
discuss the project, assign tasks, report results and share, visualize,
analyze, and store data. Through NEESgrid, researchers in Illinois will be
able to use and monitor experimental equipment in Colorado, California, Texas
or at any of the 15 nationwide NEES sites.
Lessons Learned
In addition to serving as a demonstration of NEESgrid's capabilities, MOST
also served as a platform for continued system development. The experiment was
an opportunity for the System Integration (SI) team responsible for building
and deploying the NEESgrid cyberinfrastructure to work closely with the
earthquake researchers who will be using that infrastructure.
SI team member Carl Kesselman, director of the Center for grid Technologies
at
the Information Sciences Institute at the University of Southern California,
said the type of experiment-based development was a good way for his team to
ensure that the tools being built will be useful, robust and easy to use.
"The MOST experiment showed us what we have to do," explained Abrams. Based
on
lessons learned during MOST, the SI team will work on improving the NCTP
protocol for remote system control and will implement planned fault-tolerance
features. An updated version of the NEESgrid software will be released to the
equipment sites early this fall.
The team will continue to fine-tune the NEESgrid using experiment-based
deployment. As software is dispersed to the NEES sites, they will use the
system for experiments; each experiment will provide feedback that the team
can use to further improve the system.
"The ultimate goal is that NEESgrid should be ubiquitous and seamless so
that
researchers can focus on the problem at hand-reducing future earthquake
losses," Abrams said.
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