COMPUTER SCIENCE PROFESSOR WINS NSF GRANT TO OPTIMIZE SCIENTIFIC COMPUTATIONS

Alex Pothen, professor of computer science at Old Dominion University, recently was awarded a three-year, $370,651 National Science Foundation grant to develop new algorithms and software to efficiently calculate derivatives within programs doing scientific computations.

Scientists from the Department of Energy's Argonne National Labs in Argonne, Ill., plan to incorporate the software from this project into their widely used computer programs for optimization. Engineers at the Department of Energy's Sandia National Labs in Albuquerque, N.M., will use the software to solve problems from the semiconductor and chemical industries on the most powerful supercomputers currently available.

"Optimization involves choosing the best option among many possible options available in a problem in science, engineering or economics. For example, let's say that a company is interested in getting the maximum profit for the goods it produces from a fixed amount of capital. To find the best option, often the algorithm used in a computer model of the problem needs to calculate derivatives, " said Pothen.

"As any student who has taken a calculus course can tearfully attest, this is a tedious and error-prone process, particularly when the derivatives of millions of complicated functions are involved. In the last 10 years, computer scientists have developed new techniques for computing derivatives on the computer reliably and accurately. One such technique is called automatic differentiation. Our work will reduce the time and storage needed for automatic differentiation (and other methods for computing derivatives) using a technique in computer science called graph coloring. The idea is to identify independent calculations within the derivative computations, and to pack them together into as few steps of computation as possible."

Working on the project with Pothen will be a new postdoctoral research associate, Assefaw Gebremedhin, as well as graduate and undergraduate students. Gebremedhin, a native of Ethiopia and Pothen first developed the idea for the project in 2000 when Gebremedhin came to Old Dominion for a semester from the University of Bergen in Norway. It evolved from two papers they wrote together during this visit.

"I am excited that Assefaw will work as a postdoctoral scientist with me," Pothen said. "He will be a role model for African Americans who wish to pursue research careers in computer science. On average, only one African American receives a doctorate in computer science out of about 1,000 awarded annually in the U.S. and Canada, so there is a desperate need for role models for minority students."

Pothen plans to incorporate a module based on the project into an undergraduate computer science course, and undergraduate students will help with developing and testing components of the software.