President Ohle congratulates Carolyn Dobler

Gustavus President Jack Ohle presented Professor Carolyn Dobler, Chair of the Mathematics and Computer Science Department, with the Faculty Service Award at today’s Founders Day ceremony in chapel.

I have long been interested in the parallels between “continuous” calculus and discrete calculus.  Finite difference formulas look a lot like familiar derivative formulas–with the right tweaking and summation formulas likewise resemble familiar integration formulas. Furthermore, Newton’s interpolating formula based on higher differences can be seen as analogs of Taylor’s polynomial.  In this seminar I shall present a survey of these parallels and others.  Also I’ll present a result I think is new: a discrete analog of Gronwall’s Lemma, a useful result in the theory of differential equations.  The discrete version then has implications in the theory of finite difference equations.

Pizza & beverage will be served.

Update 2009-09-27: The Free Press has now reported on this story as well.  They also give the same one acre figure as the Star Tribune did, as opposed to my 1/3 acre.  I had gotten the smaller figure from a photo caption on the Hands for Harvest web site.  But that caption referred to how much was planted the first day, as opposed to the first season.  So depending on how you read “started with,” I was wrong.  Or said another way, the expansion I predicted has already started.

And yet, in a way it is appropriate that Turing’s accomplishments be downplayed, because the statement is an apology not just to Turing, but also to “the many thousands of other gay men who were convicted as he was convicted under homophobic laws” and to the “millions more [who] lived in fear of conviction.”  Turing’s accomplishments make him a visible symbol of this group, but the wrong he was done was no greater for this accomplished individual than it was for all others similarly wronged.

The goal of the project is to reconstruct three-dimensional shape of placentas, and provide shape characterization for exploring the relation between placental shapes and fetal growth. We investigate two types of surface reconstruction methods: implicit and explicit methods.  Our  approach can be applied to any unorganized set of points. This 3D level set method shrinks an initial guess to a smooth surface on the given data. Finally, some geometric descriptors, such as surface areas and volumes, are computed based on these reconstructed models for further shape analysis.