### Leonard D. Berkovitz obituary

**10-15-2009**

Leonard David Berkovitz died suddenly but peacefully on October 13, 2009. He was born in Chicago, Illinois, on January 24, 1924.

In 1941, Len began his college studies as a chemistry major at the University of Chicago. When World War II started, he joined the military, completing meteorology training programs at the University of Wisconsin and the University of Chicago. He was commissioned as a Lieutenant in the U.S. Army Air Corps and served as a weather officer.

After completing military service, Len resumed his studies at the University of Chicago. He was elected to Sigma Xi and Phi Beta Kappa honoraries and received a B.S. in meteorology in 1946. He considered graduate work in physics, but chose mathematics and entered graduate school at the University of Chicago, receiving a master's degree in 1948 and a doctorate in 1951. His thesis, written under the direction of Antoni Zygmund, was in the area of double trigonometric series.

From 1951 to 1952, Len was an Atomic Energy Commission Postdoctoral Fellow at Stanford University. From 1952 to 1954, he was a Research Fellow at the California Institute of Technology, where he conducted research in asymptotic expansions. While at Caltech, he met Anna Whitehouse, who was working in a tissue culture laboratory at Cedars of Lebanon Hospital. They were married on June 18, 1953.

In 1954, Len joined the Mathematics Division at the Rand Corporation, where he worked on the mathematical theory of games and on a variety of tactical problems for the Air Force. He participated as a technical observer in Air Force tactical exercises and helped introduce the novel idea (now common practice) of using simulation methods for determining the outcome of tactical engagements.

In 1962, Len joined the Purdue faculty as Professor of Mathematics. He was Head of the Mathematics Department from 1975 to 1980 and Acting Head from 1989-1990. He served on numerous curriculum and administrative committees, and he remained active in research and teaching until his retirement in 2003. Eleven students obtained Ph.D. degrees under his supervision.

Len's research focused on differential games, optimal control theory, and nonclassical variational problems. He was the author of several textbooks and numerous scientific papers. Len served as associate editor, editor, and managing editor for *SIAM Journal on Control and Optimization* from 1967 to 1991. He was associate editor for the *Journal of Optimization Theory and Applications* and for the J*ournal of Mathematical Analysis and Applications*. He was a member of the editorial Committee of *Mathematical Reviews* from 1985 to 1991.

Len is survived by his wife, Anna; sons Dan M. (Michele) of Bethesda, Md., and Kenneth E. (Nancy) of Akron, Ohio; and grandchildren Elizabeth, Jonathan, Matthew, Zoe and Eli.

Donations in memory of Len can be made to the American Heart Association or to Purdue Foundation for the Leonard D. and Anna W. Berkovitz Scholarship Fund, which provides scholarships for undergraduate mathematics majors.