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china pictures

By anders pearson 11 Feb 2001

you’ve probably noticed that i’ve been rather delinquent about posting sketches lately. it’s not that i haven’t been drawing (so far i’ve gone to all my classes this semester so i’ve had plenty of doodle-time). i just haven’t scanned any in.

instead, i’ve been staying an hour or two late at work whenever i have time and scanning in photos from my trips to china. i decided that with my luck, i’d probably lose the physical copies eventually so i figured that i ought to get them all scanned in so i can keep digital copies backed up on a couple different machines and make sure i never lose them. with that in mind i had my parents send me my albums and i’ve been slowly scanning them all.

i’ve got basically three sections:

1999 trip
pictures from tucker and i’s trip in may of 1999. i’ve still got another 20 or so pictures to scan in from this one, but it’s mostly there.
1997 trip (group pictures)
these are sort of the “best of” pictures that were traded around amongst the people on my 1997 fall semester in Nanjing after the trip. all taken by various people. this set is all scanned in.
1997 (my pictures)
my own photos from the 1997 trip. i’m scanning them all in (even the boring, bad ones); got about 180 to scan in all. only a few of them in so far.

so that’s my project for the semester. eventually i’ll be done and i can start scanning sketches again (i can only take so much time scanning each day before i start to go nuts from the monotony). i’ve also got all my old journal entries from the 1997 trip at least kicking around that i’ll probably do something with someday.

and of course, all my pictures are free of those annoying, useless “copyrights” that the selfish people are so fond of so feel free to steal them (i’ve also got big, 5MB, hi-res TIFFs of them all too if you want them)

REVIEW: Visor Platinum

By anders pearson 09 Feb 2001

i got my Visor Platinum this last monday and have been playing with it continuously ever since.

i’ve never owned a PDA before (unless you count the little electronic addressbook that i won on trivia night a couple years back. i don’t) so i really don’t have much experience to compare it to. i should also mention that i am, by nature, a very unorganized person (i nearly failed out of my junior high math class not because i found the material hard (quite the opposite) but because i kept forgetting to turn in my homework (i did it; it just never occurred to me to actually hand it in so it could be graded)), so it’s probably about time i got one of these things to try to straighten my act out.

first off, it really is nice looking. the visors in general aren’t quite as aesthetically designed as the palm V’s but that metallic finish actually works for it. physically, it’s very well engineered; all the details are taken care of. the plastic cover snaps on over the back when it’s not guarding the screen, the buttons have depressions so you can hit them easily with the stylus, the tip of the stylus screws off to reveal a little pin that will let you hit the reset switch, and the other end of the stylus screws off to reveal a micro screwdriver just in case you feel like taking the damn thing apart while you’re at it. overall it feels solid; the weight is just enough that it’s comfortable without really being particularly heavy.the leatherette case it comes with is basically useless though; it’s difficult to slide the visor out of it with one hand and it doesn’t have any sort of belt clip or other mechanism to attach it to anything. all it seems to do is keep the plastic shell from getting scratched (like i really care). so i’ll probably buy a decent holder for it soon.

everyone i’ve talked to has told me, and now i finally have to agree: palmOS is really easy to use and very well designed from a UI perspective. they really put a lot of thought into how people would actually use a PDA and designed everything accordingly. i’m also pretty impressed with Graffiti. it only took a couple minutes to pick up enough that i could start using it and i’ve been getting steadily faster ever since (i suspect that the years i spent writing chinese probably helped me out a bit; by now i’m used to writing things with the order and direction of the stroke being important).

the thing that really surprised me though was how friggin cool the IR port is. i hadn’t even thought about it before i got it but, damn, it’s neat. i spent the first hour i had it gleefully beaming cards around the office. one of my coworkers made the mistake of beaming me a game called “dopewars” which will probably be my downfall (in the game you’re a drug dealer running around NYC buying and selling drugs trying to make enough of a profit fast enough that the loan sharks don’t come break your legs. it’s… um.. addictive).

i was also pretty happy that i got it to synch up with my linux box without any trouble at all (although so far, only with the serial cradle that i picked up for it). aside from periodically flaking out and crashing, kpilot has been pretty good to me. i have yet to try the gnome-pilot programs but i probably won’t bother since i figure that most of what i do aside from backups will be through conduits that i write myself (oh, i’ve got plans, i do).

the backlight does suck though. it’s got that weird inverted kind of backlight. i don’t like it much at all. but i guess it uses less power than a normal backlight so i’ll live with it.

so next i have to find a good wireless modem module for it and i’ll be in business.

anyone have any suggestions on good accessories that are worth getting (prasanth mentioned something about little stickers that you put on the screen to keep it from wearing out) and where to get them?

more wearables

By anders pearson 09 Feb 2001

yesterday, i met Greg Priest-Dorman at a demo/lecture he was giving on his work on wearable computers here at columbia.

really interesting guy. he apparently has a neurological order similar to severe dyslexia; he didn’t learn the alphabet until he was in his twenties. he first got into wearables because he wanted to be able to have his computer read to him (via the text-to-speech capabilities of emacspeak (which he currently runs the developer mailing list for)) while he went about his ordinary business. once he had this basically working, he realized that he needed simple controls for pausing and repeating sections etc. that necessitated some kind of input device that he could also wear. this evolved over the years into his own homemade chorded keyboard. his rig now also includes a display as well.

he is a big proponent of DIY wearables and spoke mostly about how to construct a rig using scavanged or off the shelf parts. he recommended using pc104 boards for the main system, powered by camcorder batteries, displayed through a Tekgear M1 head-mounted display and using a chorded keyboard built from a scavenged standard keyboard. he also ripped on the commercially available xybernaut wearables for being bulky, uncomfortable, expensive and not hackable and the twiddler chorded keyboard for being generally difficult to use.

he has also designed a wearable kit for charmed technologies that you can either download the specs for (for free) or purchase from them (for about $2000 with no peripherals). so for about as much as a decent laptop, you can get a relatively lo-tek but fairly hackable wearable rig. hmm….

have you fucked with a monopoly today?

By anders pearson 08 Feb 2001

i have.

a while back, i mentioned that IE was broken with respect to displaying images that had html in their comment field. what i didn’t mention at the time was that it was somewhat worse than that. IE5 on the mac not only didn’t display the image, but it would actually render the html, complete with javascript. this becomes a bit of a problem when you run a site that allows people to upload images but puts a lot of effort into removing harmful javascript from untrusted html. no admin in their right mind would think to scan images for javascript. if you remember all the fuss from a few months ago about “Cross Site Scripting” vulnerabilities or have a good imagination, you’ll see that this is actually a relatively severe problem.

anyway, when my coworker and i discovered it back in august or so, we got distracted and never really went beyond the “hmmm… we should probably tell someone about this” stage.

then, the other day, someone on a webdesign mailing list was complaining about IE ignoring mimetypes and i replied with an “oh, just let me tell you about IE ignoring mimetypes…” rant in which i mentioned this vulnerability we’d discovered. Kee Hinckley took it upon himself to write a quick perl script using this vulnerability to exploit a hotmail account (they work pretty hard to remove javascript from email coming in but — surprise, surprise — they don’t check images).

so, with a proof-of-concept exploit for a large site (one of probably thousands that would be vulnerable in various ways), we decided that it should be written up and posted to bugtraq.

so, if you use IE5 on the mac, IE4 on windows, (maybe other browsers too, we haven’t done too much testing yet) or run a website that allows users to upload images, you should take the necessary precautions. see the bugtraq link above for details.

Andor CCDs

By anders pearson 04 Feb 2001

Lani points out that: “With Andor, you can be sure you get dynamic range with linearity to match!”

(i admit that this post was mostly just an excuse to put up Lani’s cool yearbook photo. that’s what she gets for sending me a copy.)

EDSAC assembler

By anders pearson 04 Feb 2001

for the first two weeks of my Microprocessor Systems Lab class this semester, we were writing machine code for an EDSAC simulator. EDSAC was one of the first true von Neumann machines built in 1949. it had a whopping 2K of memory and 3 registers (an accumulator, multiplier and multiplicand). however, it was a 32-bit architecture (beating Intel by about 40 years).

anyone who’s actually written any machine code before knows that writing anything more than about 10 lines long is tedious and painful. typically, your data (variables, etc) is placed at the end of the program and other instructions access it via it’s relative address. this means that if you insert an instruction somewhere in the middle, your data has moved up a space and you now have to go through your entire program, changing every instruction that accessed data to make it point at the correct address. eg, if you had the following EDSAC code (relative addresses added for clarity): 

<br />     GK [sets the relative address base]<br /> 0   ZF<br /> 1   A143@ [add the contents of relative memory location 143 to the accumulator]<br />     ...<br /> 143 PD [an opcode that happens to have the binary value of 1]<br /> EZPF [marks end of program]<br />

and you add an instruction after the A143@, you would have to change the A143@ to A144@ as well as increment the address in every other instruction that accessed memory.

knowing that this was going to drive me nuts, i wrote a simple EDSAC assembler that lets you work with variables rather than memory addresses. so now you can just write:

GK 1
ZF 2
O [$figs] <br /> O [$cr]
O [$lf] <br /> A [$n]
TF
A [$here$] <br /> G56F [#print n]<br /> TF [#clear accumulator]<br /> A [$here$]
G88F 3
AF
T [$n] <br /> A [$here$]
G56F 4
5
PD [=n]
#F [=figs]
@F [=cr]
&F [=lf]
EZPF


and it will replace anything that looks like ‘[$variable]’ with the address for the instruction tagged with ‘[=variable]’. it also removes comments (’6’) and handles a special variable ‘[$here$]’ that inserts the current address (useful for calling subroutines via Wheeler jumps in which you have to first put the current location into the accumulator so the subroutine will know where to return to).

i know that EDSAC isn’t quite as popular a platform as, say i386, these days, but somebody might find this useful. i think next i’ll write a C compiler for EDSAC. :)

on the cusp

By anders pearson 04 Feb 2001

(the discussion on the no free will post was starting to veer more into evolution so i thought i’d start a new one.)

the first big milestone in evolution was the appearance of protein molecules that could replicate themselves; ie, DNA and the beginnings of life in general. since almost all mutations are harmful or neutral, the initial strands of DNA stayed pretty much the same from one generation to the next. things evolved very slowly for a few billion years until one day, a couple single-cell organisms bumped into each other and discovered sex. BOOM! suddenly, with genetic material getting spliced together left and right, DNA started changing much more quickly, producing exponentially more and more complicated lifeforms. multicellular life was able to evolve and evolution was in overdrive. now we’ve sort of levelled out again; but we’re about due for another huge leap in evolution.

as i see it, there are several looming possibilities for this next leap:

1) genetic engineering; pretty soon we’ll have the ability to go in and build ourselves from the ground up. there’s obviously some potential there.

2) machines; evolution and biology are robust but not very efficient or fast. technology tends to be just the opposite. machines become more like biology; humans become more like machines. either we merge and go on to the next stage of evolution together; or humans become just the stepping stone that was necessary to bring the world into the age of machines.

3) cancer. cancer is just our cells mutating and reproducing out of control. since most mutations are harmful, cancer tends to kill us. but really, what if this is the next step and cancer is just the beginning of it. at the beginning will be a lot of casualties, but otherwise, it’s sort of evolution in fast-forward. (yeah, this one’s a bit of a crackpot idea, but i thought i’d throw it out anyway.)

i’m thinking that a combination of the first two is the most likely. the third may have just been nature’s “fallback plan” if we hadn’t turned out smart enough to build machines.