Sven Leyffer, a senior computational mathematician in Argonne’s Mathematics and Computer Science division, has been re-elected secretary of the International Council for Industrial and Applied Mathematics (ICIAM). His first term as ICIAM secretary was from 2015 to 2019. He will begin his new four-year term on Oct. 1, 2019.

ICIAM has member societies from all over the world and runs the largest applied mathematics conference every four years. As secretary, Leyffer maintains the records of the organization and is involved in the day-to-day decisions at ICIAM, including the award of grants to applied math conferences in developing countries and the organization of the annual ICIAM Board meeting.

Leyffer obtained his Ph.D. in 1994 from the University of Dundee, Scotland. After postdoctoral research positions at Dundee, Argonne, and Northwestern University, he joined the MCS division at Argonne in 2002. In 2006 Leyffer (with two colleagues) received the Lagrange Prize in Continuous Optimization, which is awarded only once every three years. In 2009 he was named a Fellow of the Society for Industrial and Applied Mathematics, and in 2016 he was awarded the Farkas Prize for Mid-career Researchers by the INFORMS Optimization Society.

Leyffer’s research interests include the development of reliable methods for solving large-scale nonlinear optimization problems and the implementation and analysis of filter-type algorithms. He is extending nonlinear optimization methodologies to emerging areas such as mixed-integer nonlinear optimization and optimization problems with complementarity constraints.