It must be that time of year...Friday and today I took part in two more thesis defenses, for Brian Parrish and Paweł Pszona.

Brian is a mechanical engineering student, supervised by fellow Wikipedia editor

Mike McCarthy. His thesis research was to develop a system that can automatically analyze the configuration space of an eight-bar linkage and determine whether it can smoothly move between a desired set of poses. Somehow I got involved because setting up a system of equations describing the motion of these linkages involves some interesting graph algorithm problems. He's been working at Northrop Grumman, who supported him through his doctorate, and I imagine will continue working for them afterward.

Paweł is a theoretical computer scientist, supervised by Mike Goodrich. The topics he included in his thesis were external-memory approximation of graph

degeneracy, applications of

list labeling in the visualization of dynamic graphs, and three-dimensional

arc diagrams. For the third of these topics, he brought along some props, 3d prints of his graph visualizations, which I think make the graph structure much clearer than their 2d projections. He has also done some interesting work with Goodrich (not part of his thesis) on

making parametric search practical, and very recently published another paper with me and others on

cuckoo hashing on storage devices with limited rewrite capacity. After he finishes he will be joining navigation-system company

TomTom in Berlin.

Congratulations, both of you!