CAREER AWARD: Nam Sung Kim
Two ECE faculty members have received prestigious Faculty Early Career Development Awards (CAREER) from the National Science Foundation. These awards, which come with four-year grants of approximately $400,000, recognize faculty members who are at the beginning of their academic careers and have developed creative projects that effectively integrate advanced research and education.
Nam Sung Kim
Low-power computers could benefit environment and U.S. economy
ssistant Professor Nam Sung Kim is designing low-power computing systems that, if implemented on a broad scale, could have significant environmental and economic benefits.
When an Internet surfer opens Google and types in a keyword, the command goes to one of the company’s U.S. data centers, which are large-scale facilities with hundreds of computer servers. In the last seven years, the utility bills to power and cool the servers and auxiliary equipment at U.S. data centers increased from $15 billion to $30 billion in 2008, the last year data is available.
This cost, coupled with the amount of electricity consumed by computers in offices and homes, has consequences. “To generate that amount of electricity, we have to burn a lot of fossil fuels, and that’s not good for the environment,” Kim says. “Also, we have to perform computations for almost every aspect of our lives now, and by reducing the cost for doing these computations, our national economy could gain a competitive edge.”
Kim is crafting designs and architectures for low-power computing systems that could address these challenges. He is developing algorithms for two strategies to reduce computer power consumption. The first strategy is to program machines that can process computations more efficiently. For example, several computations must be completed for every pixel displayed on a monitor or laptop screen. Each screen is composed of tens of thousands of pixels, but a viewer would not notice if some of those pixels didn’t show up.
The second strategy is to reduce wasted energy during computations. To achieve this, Kim is trying to identify which sections, called blocks, of computer circuits can be turned off during certain functions. Turning the blocks off when they are not in use rather than letting them remain on and idle reduces the overall power consumption of the processor.
“Once the block is turned off, it takes some time to wake it back up, like it takes time to wake a computer up after putting it into sleep mode,” he explains. “To minimize performance impact, or penalty, I have to predict which blocks will be used and won’t be used in order to wake them up in time. My main objective is to hide the time
penalty so users don’t notice a slowdown.”