Older blog entries for steve (starting at number 87)

The day of reckoning for my sinuses has arrived. I check into the hospital tomorrow. Nearly every one of my sinuses is a solid mass, so the doctor will be doing several types of endoscopic surgery to get things working again. Even though it's an out patient procedure, my case is complicated enough that it's estimated to take 3 hours or so. Because of the time involved, general anesthesia will be used. I don't know yet if the doctor is using the latest laser hardware or the older rotating burr gizmo. I believe the imaging data from my earlier CT scans will be used for live tracking of the endoscope location during the procedure.

So, what are the actual procedures, I'm sure everyone is asking. Well, the first is a Total Ethmoidectomy. The posterior and maxillary ethmoids are sinuses located between the eyes. They have a honeycomb like structure made of thin bone. The goal of the procedure is to destroy and remove the honeycomb of air cells, leaving a single cavity that will drain more easily.

Then we have a Bilateral Frontal Resection and Bilateral Anterior Resection which seem to be nothing but fancy medical talk for, "we're going to blast some holes in both sides of the front and back" of something. (In this case, the something is more of my sinuses.)

And, finally, a Bilateral Sphenoidotomy. This involves enlarging openings in the sphenoid sinus. The sphenoid sinus is very close to the optic nerves and the carotid artery - let's hope I don't sneeze in the middle of this one!

Why does this whole thing remind me of the scene in Total Recall where Quaid removes the tracking device from his nose...

ODP RDF Exports

The RDF exports seem to be coming out like clockwork again from ODP. The first was riddled with errors but the second is much, much better. No illegal XML characters in either file and only one had UTF-8 errors. With luck, the next one will be error free. I'm going to attempt to create smaller RDFs of ODP subcats for those who only need one or two categories and don't like downloading the full 1GB RDF.

Gecko to music conversion using 3 bit tuples

I was driving home from work recently after a particularly stressful day when some random synapses fired in my brain (or perhaps just burned out from stress) and an idea formed...

Standard diatonic musical scales have eight notes, a power of 2 that can be represented by a 3 bits. We're used to thinking of our data primarily in terms of 8 bit bytes. But any file on your computer is just a stream of bits and could be processed in 3 bit chunks rather than 8 bit chunks. So, I thought, that means every file on my hard disk is potentially a piece of music.

I was up late playing with the Perl pack and unpack functions and eventually cranked out a simple byte to note converter that will take any arbitrary file as input and produces MIDI note data as output. After re-attaching a somewhat disused Yamaha keyboard to my Linux box, I picked a file to test the program with. I started small with a 1478 byte plain text file that contained a Backus Naur diagram of the Ring Tone Text Transfer Language. The result, while a bit odd, could be described as music of sorts. With seeming success at hand, I looked for more interesting data.

Next, I took a 24Kb JPEG photo of Nimon, one of our Geckos, and converted it. The resulting music had a Danny Elfman-like urgency to it and was a bit of an improvement over the RTTTL composition. However, the MIDI file was 500Kb and creating it consumed nearly all available memory on my box. It was at this point that I realized the MIDI::Simple module that I'd grabbed from CPAN wasn't really designed for stream use or for large volumes of data. For some reason it wants to hold the entire collection of notes in memory before writing the output.

More interesting though, was that the real Nimon seemed to take an interest in the music created from her image. She came out from under the hollow log she usually sleeps under and stood on top of it holding her head up in the air as if listening. Who knows what a Gecko hears - maybe she was just feeling the vibrations from the sounds and thought an insect was around that needed eating.

No data is lost in the conversion and it should be trivial to convert the MIDI file back into the the original data. In fact, since the music uses only one timbre and is not polyphonic, it shouldn't be too hard to convert from the music itself back to the original data. It's not an efficient data transfer medium, however. Music usually plays at around 96 or so beats per minute, each beat is just 3 bits of the original data. So a 24Kb JPEG becomes an 11 hour musical work!

Despite the inefficiency of music as a data storage or transfer mechanism, tradition says that when a new way of encoding data is found, one has to encode the decss.c file. I present decss.mid, an illegal circumvention device in C Major, Opus 3.

17 Feb 2003 (updated 17 Feb 2003 at 06:45 UTC) »

We received another BSA threat-letter at NCC Friday. That's two in as many weeks. It was the usual collection of vague threats that if we didn't rush out and buy some Microsoft, Adobe, and Macromedia software the BSA might have to search our office for unlicensed software and fine us a few million dollars. This time I called their toll free number and told them to remove us from their mailing list because we were tired of getting lame marketing letters disguised as legal threats. (feel free to call them yourself and let them know what you think of them - hey, it's a free call! 1-877-536-4BSA) I also told them we'd instituted a company-wide policy to discontinue the use of all software products made by BSA members in favor of Free/Open equivalents because of the marketing-by-extortion methods of the BSA. The girl I was talking with claimed they removed our address from their list and, after specifically asking her twice to do so, claimed she had made a note in our file about our new policy. So, will they really remove us from their list or will they put us on the list of companies to target with audits? Time will tell.

ODP finally solved the problem with RDF generation and a new RDF dump showed up on the 13th. The downside is that the dump is still riddled with invalid UTF-8 sequences and illegal XML characters. On the last RDF, I provided offsets of a lot of the errors by waiting for an XML parser to bomb-off and then looking for the problems with a hex editor (which is time consuming when you have to start over on a 1GB file after each error). This time I decided to be lazy and wrote some quick C code to do it for me. Strangely, a search on the net had failed to locate any UTF-8 or XML checkers that would work on arbitrarily large files. And most XML validators don't check for illegal XML characters or invalid UTF-8 sequences, they simple fail unrecoverably when the they hit one. Anyway, I processed the RDF files and posted a list of errors in the latest dump. So with a little luck, the next RDF dumps will be much cleaner.

6 Feb 2003 (updated 6 Feb 2003 at 06:34 UTC) »

On Sunday, Susan and I decided to go hunting for shuttle debris. I had been inspired by a fellow-DPRG member, Eric Yundt, who reported having seen a tile fragment less than an hour from Dallas in Rice, Texas. We picked up a paper and looked for any references to comfirmed debris sightings but most were too vague. And most of the debris hit in Nacogdoches and Hemphill which were too far away to make the round trip in one day.

So we decided to head for Rice, Texas. We easily found the site Eric saw on the I-45 frontage road near the Rice High School. The debris was marked by orange traffic cones and yellow crime scene tape. A local policeman was guarding it. Sometime after Eric was there on Saturday, orders were apparently issued to cover the debris. In most cases, this meant a 5 gallon plastic bucket had been placed over the item.

The police officer in Rice was not allowing anyone close to the debris and would not remove the plastic cover so we could see it. He also was not forthcoming about any other debris locations. Since the newspaper hadn't been much help in pinning down exact locations either, we were momentarily afraid we'd have to give up right there. But I noticed a van from local TV station KTVT and walked over to talk with one of the technicians. He said he'd been in Keren a little earlier. There was a lot of debris scattered around there and the Keren officials were much friendlier, too.

A half hour later, we arrived in Keren. We shortly arrived at an intersection with a police car and a whole lot of orange cones and crime scene tape. On one side of the street was a large dirt field with dozens of orange cones scattered through it. The state trouper guarding this site said we couldn't go into the field because they weren't sure that all the debris had been identified yet. However, on the other side of the street, were two pieces we could look at. He offered to remove the plastic containers so we could see and photograph them.

The first was a partial heat shield tile. The serial number was still visible but the tile was pretty badly damaged. The second piece was a completely intact tile. Small portions of the black, glass-like exterior had been damaged and the white color of interior could be seen. While we were looking at these, a couple of locals came by and started talking about debris that had landed in their yards or at other locations nearby. Most of it seemed to be tiles. However, they said they knew of one aluminium fragment that hit between two nearby churches. We got directions and headed that way.

We found a local policeman sitting in his car near the usual barrier of traffic cones and crime scene tape with a plastic can in the center. Like the state trouper, he happily removed the can so I could take some photos. This piece was a triangular shard of metal. One side had been painted and was now badly charred. The other side was bare metal and had an assortment of broken fasteners on it. The policeman said he'd seen a lot of the debris land. His description was not the view of the white contrails moving across the sky but of white contrails coming down out of the sky towards their town. Considering how much debris there was, it's amazing no one was injured.

By this time, we decided to start for home again. There was more debris in Kerens but it was all very similar. Mostly tile fragments and a few bits of metal so it didn't seem worth more time. Have a look at the photos if you're interested...

Yesterday morning, just after I woke up, I heard a loud rumbling outside. I assumed this was just a plane coming into DFW airport. The weather occasionally causes them to take a flight path right over our house that can be fairly loud. About half an hour later, I turned on the television and saw the first video of Columbia breaking up. I immediately went outside but it was far too late to see anything. The news commentators kept repeating over and over that the shuttle carried the first Israeli astronaut, implying some connection to Islamic terrorists but I seriously doubt there are many weapons that could track and hit a vehicle at 200,000 feet traveling at 12,000 mph.

I couldn't help recalling memories of the Challenger from 1986. I had been driving home from classes at UTA when I heard the news on the radio that Challenger exploded shortly after take off. I kept thinking that it couldn't possibly be correct - the reporters must be making some sort of mistake. By the time I got home and saw the video of the explosion I realized it was true. But yesterday, I knew instantly what had happened. Without the sound turned on, just looking at the words "breaking news", "Columbia" and the contrail breaking up, I knew.

The worst part back in 1986 was that I was young enough that I still believed there was some chance I'd get off this rock in my lifetime. When the Challenger accident occured, I lost that hope and knew it wouldn't happen. We'd be stuck here on Earth for my lifetime. Within days of the accident luddites everywhere were trotting out the same tired, irrational arguments against space travel and science in general; "Space travel is too dangerous for humans", "The space program is a waste of money", "Man shouldn't travel to other worlds until he can sort out the mess he's made of this one"... I've seen several of those pop up again in less than 24 hours after Columbia's demise.

Watching the contrail on CNN, I also thought back to July of 1999 when Susan and I stood in our front yard and watched Columbia cross the night sky over Texas, leaving a golden, sparkling trail of ionized plasma. I wonder how long it will be before we see a shuttle re-entry again?

The DPRG mailing list was buzzing with activity about the Columbia all day yesterday. DPRG members are located all over Texas (and beyond). They always managed to come up with stuff you don't see on the news. Eric Yundt noticed that the shuttle debris trail was visible on a National Weather Service weather radar near the Texas Louisianna border and began archiving the images. Ed Okerson assembled the images into an animation that shows the debris trail expanding and descending across the state. A later message from David Anderson, a geologist, indicated the SMU infrasound station in Lajitas had recorded the sound waves generated by the shuttle's breakup. Rather than a normal N wave, the recorded pressures waves were like nothing the geologists had ever recorded before. David said it looked more like the sounds from a ripple fired mining explosion. David has put up a web page with images of the sound waves that were recorded. (he contacted NASA as well, since his data covers a time period after NASA lost telemetry data)

One last thought is what Richard P. Feynman said in his controversial appendix to the Challenger report, "The shuttle flies in a relatively unsafe condition, with a chance of failure on the order of a percent (1 in 100)". If you ever get the chance, read "What Do You Care What Other People Think?: Further Adventures of a Curious Character" which has the full account of his investigation of the Challenger disaster.

30 Jan 2003 (updated 30 Jan 2003 at 06:24 UTC) »

Medical Mysteries

"You have the sort of sinuses an ENT dreams about" - not what you want to hear from your doctor after a CT scan. About four months ago I had a cold. A month later I still had it and began to suspect it wasn't a cold. My ENT thought it might be an allergy. This was a depressing thought as I've never had allergies before and didn't look forward to being unable to breathe through my nose for the rest of my life. He put me on Zyrtec and Allegra. Another month later and things were worse, not better. The doc ordered a CT Scan. That part was actually pretty cool; lying face-down on a platform that moved linearly in and out of a rotating ring within a huge, pivoting mass while red targeting lasers lit up my head.

The result of the CT scan was a series of about 35 cross sectional views of my head. It was a coronal view, so it only covered the front third so of the head. But it was enough to show that all my sinuses, which should contain nothing but air, were solid masses. At least one was begining to calcify. So the fix is to perform, lets see, a total ethmoidectomy, a bilateral frontal resection, a bilateral anterior resection, and a bilateral sphenoidotomy. Three hours or more of nasal roto-rootering.

The immediate next step is trying to get the insurance company to approve the procedures...

When I get time, I plan to scan the CT images and maybe try to assemble them into a nice 3D view of my head.

ODP News

RDF export is still broken. Overall performance is still degrading rapidly - a lot of folks haven't been able to access the public site at all lately. Since the ODP software isn't designed to scale beyond one physical server and there's nothing faster than the 16 CPU Sun 4500 handy, they decided to give priority to the editors by throttling back public access. So we can edit to our hearts content but you can't see the site or use the RDF exports. The one developer who maintains the entire dmoz/ODP system and codebase is doing all she can but AOL won't allow outside help because it's proprietary code. So we're keeping our fingers crossed that she'll get things fixed but I have to admit that I'm not too optimistic at present. Not a happy situation.

There's been a lot of talk about starting a new directory project to fill in the ODP gap with something new that's not controlled by AOL and that's not just Open Content but Open Source/Free Software as well. I've gotten email from several interested editors who want to work on the project and have been talking with two other programmers who've been working on a clone of the ODP software for a while. If anyone else is interested, or has some ideas feel free to contact me.

The Dangers of Blogging

Someone I know just lost her job for saying the wrong thing about the wrong person in her weblog - yikes!

I'm suprised this hasn't appeared on Slashdot yet but I found it interesting. A study of one of the root name servers done by researchers at the San Diego Supercomputer Center shows 98% of queries it handles are unnecessary. 70% of the queries are duplicates, 13% are for bogus TLDs like .elvis, 7% are queries that already have an IP address in them, and 8% are assorted other minor unnecessary crap. If the root name servers were anything like our DNS servers, 90% of the queries would be unauthorized attempts to update zones coming from broken Windows boxes...

Well, I suppose it's a bit late to be posting new year's resolutions so I'll just skip straight on to other things. I've picked up a couple of new ODP categories to play with. ODP still hasn't gotten the RDF export fixed. They seem to be having some major scaling issues right now. Wish they'd accept some help from the many editors who've offered but they seem determined not to.

The DPRG had to find a new meeting place this year. For several years we've been meeting at the Bill Priest Institute. Starting this month we've been offered meeting space at The Science Place, where we usually hold the Roborama and other competitions. So expect to see more robots and hackers wandering around The Science Place this year.

29 Dec 2002 (updated 29 Dec 2002 at 04:39 UTC) »

My recent discussions with the ODP guys about open-sourcing the ODP backend software have led me to read up on RDF, which is the format used by ODP for exporting the ontological information and content of the directory. One thing I immediately ran into was XTM, the ISO standard for creating XML Topic Maps. These seem to me to be competing standards in that they both use XML to describe ontological information. RDF seems to be enjoying much more widespread use on the web but I'm playing catch-up in this particular area right now, so I may be missing some uses of XTM. One helpful document I've found is a paper by Lars Marius Garshol comparing XTM, RDF, and two RDF extensions, DAML and OIL. If anyone knows of other introductory-level documents describing the similarities and differences of XTM and RDF, I'd be curious to hear about them.

Another Christmas has come and gone. A few of us gathered at my sister Linda's house and joined her family for Christmas day. The usual sorts of holiday activities occured - food, games, lots of talking, and helping the kiddos assemble a few toys. And we made some calls to those who couldn't (or didn't wish to) come.

We decided to take today and tomorrow off work as well. Today we visited a few of the antique malls on highway 80 near Forney and saw everything from an antique Russian MIG to a Jeanette Cube cup and saucer that Susan had actually been looking for. We brought the cup and saucer home with us but left the MIG - it had too many rivets.

I closed an eBay transaction today that has been pending for some time. I've been searching for a particular Canon FD macro lens for nearly a year. Earlier this month I finally found one in good condition and managed to nab it at the right price on eBay. Unfortunately, the seller was located in Guam which was hit by a major typoon within hours of my winning the auction. After a few days the seller did manage to get an email through saying they had no power, no water, no public services of any kind (including mail), so no lens. This week, however, the seller made it to California and is shipping all his eBay stuff from there. So by this time next week I may finally have my new lens to play with.

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