STP: What was I thinking?

Hey guys.  So there’s this thing I signed up for, it’s called STP, or Seattle to Portland.  It’s a 200-mile bike ride between – you guessed it, Seattle and Portland.  It’s spread out over two days, but if you’re as un-athletic as I am, that’s still a pretty tall order.  I’m not sure whose bright idea it was (Dax), or why I succumbed to the peer pressure to join (Lora), but our lab group is now officially in.  That’s right, all of us, including our advisor, Will.

I’ve done one training ride (ie. a ride that’s longer than my commute).  It was last Tuesday with Dax.  Google maps tells me that it was about 30 miles in total.  It took me 2.5 hours.  Awful.  I thought I was dying, especially at the end.  My house is on a hill, so the last five miles or so were just a kick in the teeth.  As soon as I got home I wanted to eat like five pounds of poutine.  Which, luckily, was not available to me at that point.

Tomorrow, Sunday morning, we have another training ride planned.  This time we are making the (to me) very ambitious journey to the Red Hook brewery in Woodinville.  That’s a total of about 14 miles longer than what we did on Tuesday.  Only this time it’ll be with Rob and Lora too.    The very best part of this plan is that in the middle of those hellish 44 miles, we are stopping for food and beer.  Sweet nectar of the gods.

Here’s a crappy little drawing I made.  I hope it illustrates how I feel about the ride we’re supposed to do tomorrow morning.

Interview with Dad

I made this months ago when I first started interviewing Dad – I have since recorded more than 4 hours of audio, but haven’t had a chance to put any of it together.  This was done using Hindenburg Journalist, which I briefly reviewed at the time.

This little audio clip is is mostly Dad telling some stories about his childhood in Austria during World War 2. It’s about 15 minutes long, and the only way I could upload it to my blog was by reducing the file size to under 10 MB. This required saving as a low quality mp3. Hopefully it doesn’t suffer too much from this reduction.

Dad Interview – Part 1

Lloyd’s mirror and BBQ chicken

Hey, here’s my drawing from yesterday. It was an inverse theory day. I think that the conference got me all fired up about inverse theory for some reason. It might not be the best idea ever to change my term project two weeks before the end of the term… but my other project is sort of boring.

A whole chicken! A whole bottle of wine! And some inverse theory.

I’m in the process of writing code to do a couple of things. The first is to locate a whale (or any source) in the water column using earthquake location techniques. I’m assuming that I correctly pick the direct path arrival. So that part should be easy. I’m running it several times on an array of grid points.  So for each point I get a cluster of detections, and then I grab the eigenvalues and eigenvectors to get the semi-major and semi-minor axes (with orientation) of the error ellipse.  As you can imagine, this takes a long time.  It’s an iterative least squares problem, being done like 6500 times * 50 iterations for each time.  And 50 is sort of low.  Hooray for the brute force method!  Here’s a little peak at just one of those iterations.  Because the whale is not in the network, the position is not great.  It’s really difficult to resolve the range, in particular, although the bearing seems better constrained.

Fifty independent solutions for the location of a whale near a seismic network.

The second bit of code I’m writing up is not actually finished yet.  Or started.  All I have is the math, which tends to be the tough part anyway.  The whale call arrives at our seismic network via several paths.  There is sometimes a direct path arrival, but often multipaths, which have interacted some number of times between the surface and the bottom.  The multipath structure will change depending on where the whale is, and theoretically, it is possible to back out at least a range and depth using the multipath arrival times.  Again, this is a problem that has been solved before.  But it’s fun to figure it out for myself.

Some other things I’ve been thinking of trying:

  • Combine several range solutions from the multipath arrivals to locate the whale.  This shouldn’t be very hard.  It’s just like positioning a pinger on the bottom of Portsmouth Harbor!
  • Implement some kind of adaptive tracking algorithm… I feel some Kalman filtering coming on…

What the bjerrum??

Drawing-time study break!

...but I am le tired.

So I tried to do this homework problem where we calculate the horizontal forces contributing to ridge push.  Just a simple little calculation based on the differences in pressure calculated at some compensation depth beneath the ridge and at some distance away from the ridge.  No problem.  Imagine my surprise when I discovered that instead of the plates being pushed apart at the ridge, they are in fact being pushed together.  Which breaks several laws of physics, and doesn’t match observations either.  Brilliant!

Now, back to practicing my presentation.  Look out fin whales!  You will be counted!  (To some statistically quantified uncertainty level!)

Seismometer at UNH

Hey there, blog readers (yes, both of you!)

I’ve been super busy lately, so no posts.  But I’m going to cheat, because Monica just posted something cool enough for me to mention on her behalf.  She announced on her blog today that the University of New Hampshire has its first seismometer!  Woo hoo!  For now it’s installed in a vault beneath James Hall – how mysterious and exciting…  Check out her pics and descriptions here.

Finally discovered Evernote

I’ve been meaning to check out Evernote for a while now, but the tipping point was really this morning when I saw Kurt’s post on Facebook about using it to record a meeting.  And generally, if Kurt has an opinion on some tech gadget or software, I’ll listen.  He didn’t actually give an opinion, actually, but it was enough to send me to the App store to see for myself.  It was way cooler than I thought it would be.

You can write notes in all sorts of formats – text, images, websites, web clips, iPhone photos, scans, PDF’s…And you can really easily synch your iphone, ipad, desktop, or laptop anytime you have an internet connection.  You can also access your notes online.  The notes are stored on a server somewhere, but as far as I can tell, the full installation + notes gets installed locally on computers.  I’m not completely sure what happens with iphones and ipads, though, they might just access the cloud directly for everything.

I could go on about it, but there’s lots to find elsewhere on the internet.  But one of my favorite features is the handwritten text recognition.  I tried taking an iphone snapshot of some notes I took during Rip’s Master’s defense today, and then used the iPhone app to upload them to Evernote.  Even with my messy handwriting, it was still able to find some important words.  Here’s an example:

Not bad!  I also like how it can show you a map of where you took certain notes:

I’m probably jumping the gun, but this seems incredibly irresistible to me.  Sorry, Org-Mode!