For pioneering research in disturbance and landscape ecology and in modeling of land-use change with its implications for global changes, which have influenced environmental decision making on a worldwide scale.
For internationally recognized contributions in distributed and cluster computing, including the development of the Parallel Virtual Machine and the Message Passing Interface standard now widely used in science to solve computational problems in biology, physics, chemistry, and materials science.
For innovative and fundamental contributions to the understanding of the interactions and transport of electrons in gases and liquids, negative ion processes, the interfacing of the gaseous and condensed phases of matter, and the use of fundamental knowledge in the development of gaseous dielectrics, radiation detectors, and pulsed power
For fundamental studies in radiation physics, radiation dosimetry, and surface physics and for pioneering theoretical work on collective electron modes, surface electromagnetic waves in solids, and elucidation of the interaction of charged particles with matter.
For applying molecular beam techniques to study chemically reactive collisions, helping to lay the foundation for the present field of chemical dynamics, and for pioneering studies in accelerator-based atomic physics, ion-solid interactions, and the channeling of ions, electrons and positrons in crystalline solids.