Sorry the posting has been so light lately. I had a whole list of topics I wanted to cover back in January, but I’ve just had an impossible time getting up the time, desire, and mental energy to blog lately. Part of it has been due to tooth problems–I have a tooth that needs a root canal, and I had been putting it off for a while since it hadn’t been hurting. The pain flared up all of the sudden this last week, and even with the antibiotics helping with the inflammation, I’ve been feeling lousy for most of the past week.
Another part of it has been how busy I’ve been at work, with my cub scout den, and with my thesis.
Work is going pretty well. We’ve been doing a series of fixes/upgrades on our vehicle based on some of the things we learned from the first hold-down tests. We’ll probably blog some results later next week.
Scouts is going fairly well. We studied first aid this last month (including having a nurse from the local hospital come with some CPR dummies to demonstrate rescue breathing and the Heimlich maneuver), and are starting Engineering this month. One of our projects we’re working on this week is building catapults. My coworker Ian was helping us, but his design was gnarly enough that it was too big to fit in his station wagon afterwards, so I’m working on some scaled down models. In spite of what he thinks, while it’s a good idea to build something a little bit manlier than those pansy popsicle stick catapults in the scout books, 10 year olds really don’t need to build a catapult that could lob a bowling ball 100 yards…
My thesis has also been moving forward a bit. I got a blog comment from Carl Feynman with a link to an online book discussing closed-form solutions my particular question about Bessel Functions. I also figured out a better, more tidy way for doing the math in that model than the approach I had been taking. More importantly, I found a good paper discussing fluid flow in a tube with pulsating walls. The math is a bit hairy (Bessel functions, Fourier Expansions, and Complex Numbers, oh my!), but I’m slowly working my way through it. With luck by sometime next month I’ll have that all tied together into an integrated model.
Which brings up a question. Would any of you be interested if I published at least the modeling portion of my thesis on the blog? Kind of like a serial novel, but with ugly math instead? Or is that more pain than most of you are interested in?
Lastly, I’ve been enjoying watching our two little boys grow up. James is still our cute little Mr Wide-Eyed Wobbly-Neck, but he’s getting some neck muscles. Jonny can now open all the doors in the house, figured out the “child-proof” doorknob covers, and likes “sharing his toys” with his little brother. Which means that we walk into his room, and James is half-way buried in toys with this very consternated look on his face, while Jonny is giggling uncontrollably. I’ll have to post some pictures sometime.
Jonny’s also really into trains, which he calls “Hoo-Hoos”. We went to a model train shop in town today, and boy was he was so excited. You should’ve seen the look in his eyes when the store owner turned on their little train track for Jonny to watch. He was stoked.
I asked him afterward “Do you know how to say train?”
He emphatically replied “Yeah.”
So I said “Ok, say it then.”
He said “Hoo-Hoo!”
Cute.
Anyway, I’m not sure if I’m going to get the time or the mental energy to post much space related stuff this next week, but I figured I’d let everyone know what I’m up to.

Jonathan Goff

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Jon –
My son used to be a total train nut and he loved to watch train gifs on the computer. Here are a few links and there are many more if you google “train gifs” — its all amateur stuff with many broken links but there are a few good moving scenes and even at age 3 my son was able to select his favorites from bookmarked links.
http://www.dhke.com/traingif/
http://www.frograil.com/gifs/gifs.htm
Also, there is an extensive series of videos called “I Love Toy Trains” that are well done:
http://www.tmbooks-video.com/videos.htm
Hi! I was recently thinking about the old friends I’ve lost contact with and decided to “google” Tiffany. Unfortunately I couldn’t find any contact info until I stepped out of the box. My name’s Michelle and I went to school with Tiff (Spiff) Cragun from Monroe to Sheldon. Please, if you read your comments, send my love to her. And my congrats to both of you and your lovely family! Michelle Foster mfoster42@gmail.com
Jon,
You are certainly finding out that while you thought you had “no free time” with one child, when the second one arrives, you look back on the time with one child and wonder at all the free time you actually had by comparison.
Don’t sweat it. You adjust. Things are never quite the same again (at least until they all move out) but what replaced the free time you had before is much better in the long run.
Twenty minutes with Jonny and the “Hoo Hoos” is waaay better for all concerned than even 10 minutes with us (as much as we like the conversation). If ever you are wondering about choosing between Hoo Hoos and blogging, smack yourself in the head and go to the train shop. Hoo Hoos will become “trains” fast enough and the moment will never come again.
Us old farts will still be here when you find the spare moments.
Paul
Hey, if you do want to cut and paste portions of your thesis, I’d be interested! Nothing cooler than rocket science. 😉
We got our son an HO model train set when he was in grade school. We had good times with it. Unfortunately, we didn’t have room for it in our house at the time, so it didn’t get set up very much
Michelle,
I passed your email along to Tiff. She was excited to hear from you.
~Jon
Paul,
It’s not so much that I don’t have time to blog lately as that I haven’t had anything that interesting to talk about. Well, I guess I had a whole bunch of half-baked ideas that I was trying to get ready to blog about, and I kind of lost momentum on all of them and they’re still all half baked.
~Jon
Tom,
Alas, the thesis has very little to do with rocket science. It’s just brutal math, piezoelectricity, and fluid dynamics. But if you’re interested, I’ll start posting things little by little.
~Jon
I’d second thesis info. I find that kind of stuff interesting 🙂