## Thursday, September 2, 2010

### A new semester

So a new semester just started. A few cool things have been going on:

1. I signed up for two classes: "Adaptive + Multigrid Methods" with Luke Olson and "Finite Element Analysis" with Dan Tortorelli.

The class on Iterative+Multigrid Methods is about techniques for solving large systems of linear equations. Large systems of linear equations arise a lot from approximating a partial differential equation by a separate linear equation at each point on the mesh. "Iterative" means that you solve the equation by coming up with an approximate "guess" and then repeatedly improving the "guess" until you get close enough to the solution. "Multigrid" means that rather than just using one mesh, you have several different meshes of different sizes, and you use the solution to the coarser mesh (which can be computed faster) in order to get a better guess for the solution of the finer mesh.

The Finite Element Analysis class is in the mechanical engineering department, so most of the students are mechanical engineering students. It is interesting to learn more about how the mathematical techniques I am learning about are actually used to model physical systems, although one problem (from my perspective) is that since most of the students are not computer science students a lot of time is spent going over basic programming concepts that I've already seen over and over. For example today the professor spent most of the class just explaining how to write a program that reads input from a data file and puts it into a matrix.

2. As for my research, we have gotten to the point where we can produce reasonably good looking visualizations of the meshing process. Once I finish that part (probably in the next few weeks) I am planning on making a web page where I can put them up so you can look at them.

3. In Belegarth, last week there was the Numenor "Opener" to mark the start of the semester, where lots of people come, including some from other groups, and they do lots of different battles. One of the battles was a "Unit Battle," where the different "units" (units are groups of people that fight together and often have distinctive uniforms) all fight. For that battle I temporarily joined a unit called House Valdemar. During that battle the leader of that unit (who is also the owner of one of the game stores I play Magic at) was so impressed with my archery skills he asked me to join the unit. The way it works is that now I am a "petitioner", and after a couple months the members vote on whether to keep me in as a full fledged member. So I guess it's kind of like a fraternity (not that I would know).

4. I have volunteered to be an instuctor for a 4-H club activity that teaches kids how to build robots using Lego Mindstorms toys. The way this happened was that one of my classes is in the engineering building, so when I was getting out of class I saw a flyer up on the wall advertising this, and it sounded really cool. It's going to be an hour once a week for 6 weeks, and it probably going to start in a couple weeks or so (they haven't set up the schedule yet). I did check to make sure it will end before December so it won't interfere with our vacation plans.

Dan Mont said...

Hey Alex, this all sounds great (except for the having to listen to the basic programming stuff). You seem to developing a lot of expertise in both solving systems of non-linear equations and beaning people in the nose with soft-tipped arrows. now if you can only find some clever way to combine those skills.....(just kidding).

I think the volunteer thing sounds great, too. It's always nice to do something a little different and to help people out. How old are the 4-H kids -- high school?

I'm looking forward to seeing your meshes on line.

Mom is now back in Vietnam, so I am much happier. Pluus a couple old friends of mine are visiting us at the end of the month. That should be fun, too.

Dan Mont said...