Scientists open their eyes
to visualization's potential
(Page 2 of 4)
Johnson and Wes Bethel of the National Energy Research Scientific Computing Center (NERSC) and the Visualization Group at Lawrence Berkeley National Laboratory (LBNL) co-direct the Visualization and Analytics Center for Enabling Technologies. VACET is part of the Department of Energy's Scientific Discovery through Advanced Computing (SciDAC) program.
"Visualization works," Bethel says, "because it is able to effectively leverage a high-bandwidth link into one of nature's most advanced signal processing systems: your brain."
Like any motion picture, a scientific visualization presents a final cut: selected and processed data from much larger data sets. Visualization can reveal underlying meaning and structure in science and engineering data, typically generated in simulations that incorporate mathematical computation and geometric models.
Johnson explains.
"I'm drinking a cup of coffee &ndash a double latte &ndash right now. Let's say that I made this too hot when I oversteamed the milk, and I would like to understand when it is going to be just the right temperature for me to drink.
"As a physics problem I would need to model the physics of the thermodynamics of the temperature. And if I really wanted to make this accurate I would have to model the geometry of the coffee cup, and I would have to take into account the material properties of the coffee cup.
"Then I would need to approximate that mathematical model in this geometric computer model and that is the computer simulation where I would approximate the continuous mathematics. I'm going to see a visualization of the decrease in temperature over time as my coffee cup sits there interacting with the air around it."
A single visualization now can display data in the terabytes (a trillion bytes) and petabytes (a quadrillion bytes). Compare that to Google, which processes about 20 petabytes a day. A few seconds of animation may consume a million processor hours of computing time, but the payoff can be an exquisitely detailed vision of realms no experiment can probe. And increasingly powerful computers are leading to higher resolution views of simulated reality at extremely fine grain &ndash even at the atomic level.
