September 2022

S M T W T F S
    123
45678910
11121314151617
181920 21222324
2526 27282930 

Style Credit

Expand Cut Tags

No cut tags
Tuesday, March 25th, 2008 07:52 pm
What am I up to, you may be asking1? Well, classes are almost over. I have 2 more assignments to do, one huge and one pretty small. But mostly, now that I have a supervisor, I'm focusing on the 3 class projects due at the end of April. No finals this term, which is nice, but that means projects instead.

Image Understanding II: I'm implementing this paper, adding image features from several others, in order to create a generalized image quality assessment for the SRVC project. Basically, we want to screen out cartoons, paintings, illustrations and renderings, while at the same time ranking the remaining images by how good they are for training a classifier.
Status: Pretty good. I have the paper implemented, and I'm starting to add the new features. I have a decent training set downloaded, but it could use some more work.

Sensorimotor Computation: I'm implementing some visual tracking/servoing on the eye simulation hardware. Not entirely sure what, yet. Basically GYRE in one dimension, with a motor instead of compressed air thrusters. And no freefall.
Status: The person who really knew how to run the system left in December, so it took me about 3 weeks to even get it running again. But this weekend I started working on the new code, which so far hasn't been that hard. I need to implement some kind of PID control loop now.

Machine Learning: For reasons that are too arrogant to be written down, I want to find a way to match the states in two or more Markov processes as equivalent, given just the initial probabilities and the transition table. As far as I and the professor know, no one has ever done this before. And since I'm dealing with (in the test data set) 94 states, I'm basically searching a 94! permutation space. And this is by far my weakest area. So, good times.
Status: lol

1: It's okay if you're not actually asking this.
Wednesday, March 26th, 2008 03:34 am (UTC)
1: It's okay if you're not actually asking this.

Actually, I've been curious, but you operate outside of my areas of expertise, so I have to research what some of that means.

Wednesday, March 26th, 2008 03:36 am (UTC)
I'm happy to explain more as needed, I just didn't want to clutter up the post with details no one cared about.
Wednesday, March 26th, 2008 04:21 am (UTC)
Sadly, my knowledge is lacking here.

1 is pretty self-explanatory, though I could argue quite a while about using this sort of system to quantify quality, but that's just me being a photographer. I do find some of their feature set for a quality photo to be very interesting (and true).

2 is pretty clear, but I'm curious as to what the final outcome desired is. Obviously, I know very little about what you've been working on.

3 loses me, 'cause I fail at this type of geekery.
Wednesday, March 26th, 2008 04:40 am (UTC)
Certainly I don't think 1 really judges image quality, and I doubt the authors think so either. But it does seem to make a decent stab at it, and more importantly it is looking at exactly the features I'm interested in. We want crisp, well-lit, well-framed pictures for training the SRVC classifier on. Product shots, really. This won't be perfect, but it should do a pretty good job at filtering out some of the dross that comes with any Google Images search.

I'm not sure on the outcome for 2, either. Basically, I just want to get good marks. :) The stuff I've been working on so far is using image features to visually detect and counteract rotation in the platform, much like GYRE. Once I have that working well (it's either very slow or unstable atm) I'll try making it track objects the move in front of it. Since this is all in MATLAB, the interface on something like that becomes tricky.

A Markov process is one where the probability of being in a given state at time t is entirely given by the state it was in at t-1. They're surprisingly useful for linear systems, like language, movement or DNA. Assuming discrete states for convenience, they're defined by a table of starting probabilities for each state, and a table of the transition probability for each state to every other state. How likely is a 'T' to follow a 'Q', etc. So I want to take two sets of tables like that, and assume that the underlying states are the same. (Say, to hint at my real goal, one is taken from the symbols of a syllabic language and one is taken from a transcription of people speaking that language.) I need to find a mapping from states a,c,b in the first set to states 1,2,3 in the second. The permutations add up really quickly, of course. It's very likely untractable unless I come up with something very clever. =\
Wednesday, March 26th, 2008 04:41 am (UTC)
For reasons that are too arrogant to be written down

Rock! You are a badass.
Wednesday, March 26th, 2008 04:58 am (UTC)
I have to admit that I wondered how little roboticists are made.

I think you mean 94!, not !94. The problem you describe reminds me of something I've heard EDA (electronic design automation, i.e. digital circuit design) people call the "subgraph isomorphism" problem, which I think has to do with determining equivalence between FSMs. Yeah, like so many interesting problems it's NP-hard, but who knows? Maybe you might find something in that literature useful.
Wednesday, March 26th, 2008 05:01 am (UTC)
So fixed.
Wednesday, March 26th, 2008 07:11 am (UTC)
Totally random and off-topic, but I don't "see" you online anymore--what's the chances of getting loan of your forge? Seeing as you are up in Canada and not using it...

Teammate and I are going to tackle some stock-removal knives, but will need forge-like temps to do hardening afterwards (start with fully annealed tool steel).

Thinking we can do that with a hollow fire brick and MAPP torch, but then thought about your forge.

-B.
Wednesday, March 26th, 2008 07:16 am (UTC)
It's at my parent's place in Spokane, I'm afraid. Hacking something up shouldn't be too hard, though. You might want to see if [livejournal.com profile] corivax/[livejournal.com profile] caladri still have some firebricks left over from their furnace. Or maybe you could use [livejournal.com profile] niac's forge.
Wednesday, March 26th, 2008 07:18 am (UTC)
Hrm, is there opportunity to borrow it from there (Spokane) if I'm going to be over that way in the next month or so? (If it's buried in the back of storage container or something like, understand.)

-b.
Wednesday, March 26th, 2008 07:22 am (UTC)
It's buried somewhere in my parents' garage/barn. I think the chances of getting it out easily are pretty low. I'm not even entirely sure where the regulator ended up, since that got forgotten during the first trip. Sorry.
Wednesday, March 26th, 2008 07:29 am (UTC)
That's cool. Now I have no excuse not to make my own solution. Man, burner design is sexy. They are simple carburetors! I really don't need a "real" forge for my purposes, but it's tempting to at least make a coffee can/paint can size one for the sake of it.

-b.
Wednesday, March 26th, 2008 05:16 pm (UTC)
Hi there. :)
Wednesday, March 26th, 2008 07:36 am (UTC)
Mm, so much geekiness, compressed *just enough* that I can still follow it.

And yes, I was curious.
Wednesday, March 26th, 2008 06:46 pm (UTC)
I was definitely curious. :) Aaaand feeling like my brain went "TILT" on reading the explanation, but that's okay, it's still good to know what you are working on.