Rambles In The Brambles

Los Angeles is a huge metropolis, but it takes less than an hour to get from the sprawled suburbia to the quiet of the mountains. I find it necessary to occasionally breathe thinner air and to push exhausted muscles up just one more slope.

This past Saturday, my friend, Jim Leigh, and I did some trekking in the San Gabriel mountains, north and east of Los Angeles. We chose to start near Mount Baldy, a familiar spot for both of us. We hiked up Icehouse Canyon, to a saddle, and then eventually made our way to the Timber Mountain peak. The entire trip was a bit over 13 miles, with a climb of almost 3500 feet. The attached photographs were taken on that hike.

	My 2002 Acura RSX Type S. It gets me where I am going. This was taken at the trail head.
	Icehouse Canyon is a mixture of light, shadow, water, and rock.
	There were numerous ruins in the lower part of the canyon. It is close to Mount Baldy Village, so perhaps it was once more popular.
	The view of Telegraph Peak from the upper part of the canyon.
	The Icehouse Saddle was at the top eastern edge of the canyon. There were paths to several nearby peaks. This is a view of the western side of the saddle
	The path leads ever onward...
	Telegraph Peak on the right, with the snow-capped Baldy on the left.
	Jim Leigh, on the trail towards Ontario Peak. The snow was very hard and icy, and we were not equipped with crampons or ice axes. We chose to backtrack to the saddle and choose another path.
	Ontario Peak, from below. Maybe some other day.
	The day was quite clear, and fine-grained structure could be observed on even far-away canyons.
	The northeastern view from the top of Timber Mountain. Far below, I-15 runs to the desert.
	More desert-views from the top of Timber Mountain.
	Snowy San Grigornio, standing tall 1500 feet higher than Timber Mountain.
	On the path down the mountain, this fossilized tree stump was observed.
	Running water in Icehouse Canyon.
	Streams and falls, fairly close to the trailhead.

Posted by Jeff at 10:32 PM | Permalink | Comments (5) | TrackBacks (1)

I wanted to be able to embed tags into an entry, perhaps in a hierarchical sequence. The tags would contain the photo path, and some text description. These tags would be parsed into a proper HTML table, that would be pleasing to view. I imagined an XML format, perhaps with a container entity so that one's photo entry could have a pure text prelude and a conclusion.

My first attempt at this is located here. This may be useable, if only barely. There were some good lessons learned, though:

• Normal MT tags cannot be used within entries. I probably should have know this. It is somewhat unfortunate, as MT has a great tag scheme for its templates. The only way to be able to do processing of entries is via a text-formatting plugin.
• It is difficult to include XML tags in a text-formatting plugin, for at least two reasons. First, the MT editor automatically changes strange < and > signs into the appropriate thing for HTML. That means that they are not passed into the text filter. Second, even if they were passed in, I probably would not be able to use an XML parser, as there may be text before and after the XML tree. (Maybe that can be handled with some parsers, but I don't know how.)
• Plugin installation is surprisingly easy. But, I was originally frustrated when I could not get normal MT tags to work in my entry. I was then frustrated when I misspelled "Plugins" as "Plugin". I guess that I am easily frustrated. Still, most of my computing career has been on the Windows platform, so installing a module by dropping it into the right directory makes me almost giddy with joy.
• Because I could not include XML-like tags into the entry, I had to parse for bare text. I tried to make the syntax obvious by capitalization and end-tags (like XML without the brackets). It seemed easiest to write the parsing code in a "stateless" way, but I recognize that is not a very maintainable way of doing it. Wow, do I want to use a real XML parser.
• There seems to be some good documentation out there. Timothy Appnel's writeup was an excellent introduction. The original discussion of the text-formatting plug-in feature is described here. The MT manual contains some information about plugins. The best place, of course, is the Plug-Ins Directory. It is almost a necessity to look at some working examples.

Well, I will continue to think about the issues in doing what I am trying to do. Perhaps there is a reasonable solution. I am far from a Perl guru, and maybe some wise master has already uploaded what I need to CPAN.

I continue to be impressed with Moveable Type and the community that has grown up around it. Perhaps if I can work out my issues, this little plug-in will be useful to others, too.

Example of what I am trying to do:

	Here is some text.
	Here is some text.

Posted by Jeff at 07:05 PM | Permalink | Comments (0) | TrackBacks (0)

I haven't written much in the last couple of days, so I thought that I should "wave the flag", so to speak. This photo (click on it to see a larger version) was taken at the Santa Monica beach on Sunday. Because the weather was warm and clear, a large number of beach-goers have crawled out of their winter holes. Note the Palos Verdes Penninsula on the far left, the shadow of Catalina Island on the horizon, and the numerous sailboats on the water.

Posted by Jeff at 12:20 AM | Permalink | TrackBacks (0)

If I could haul this 75 kg of meat into space, I would do it. But unfortunately, it is too expensive. And given rocket technology, it probably will always be too expensive. What can be done? Answer: Build a bridge.

The price of a place on the Space Shuttle goes for over $9000 per kilogram (assuming that the Shuttle program will continue). Conventional rockets might get the price down to about $1000 per kilogram, but that is still simply too high. How can mankind haul the massive tonnage needed to really colonize the moon, planets, and stars? Consider a developed inner solar system: Rockets would be a massive barrier to commerce, almost like choosing to ferry cargo over a river rather than bridging the shores with a superhighway.

Why are rockets awkward? I think that the problem comes down to the rocket equation: Large objects require a lot of fuel to get off the ground, and that massive amount of fuel means that the object gets larger. The only way to transcend that problem is move the fuel out of the capsule: Spend energy moving the cargo, not moving fuel that will be burned up anyway.

I first ran across this idea in science fiction books. Arthur C. Clarke used space elevators in his book Fountains of Paradise. Fredrick Pohl also had an accelerating "ribbon" in his Gateway series. Kim Stanley Robinson used cables in Red Mars.

Some have used the space elevator concept as a necessary step in the development of space. Marshall Savage, in his opus The Millennial Project suggested using a train-like system that would accelerate cargo to escape velocities. Savage cannot be faulted for thinking small: The train is just an early stage in a detailed plan to colonize the entire galaxy. His driving thought is interesting: Humanity must expand, or it shall fail.

But the space elevator is (slightly) more than just speculation. NASA Institute for Advanced Concepts awarded Highlift Systems with a grant to study the elevator concept. They appear to have a detailed feasibility study worked out. They recently spun off another company, Liftport, to work on the commercialization of the elevator. The goal is to have the first cargo by 2018. The elevator concept has also been discussed widely by experts, as reviewed by Space.com.

The major technological barriers right now include the development of extremely strong materials (such as carbon nanotubes). I think that the technological barriers will be overcome as time goes on... The major difficulty will be to build a strong enough business case.

I hope to see such things in my lifetime. I would be proud to participate in the development.

Posted by Jeff at 10:12 PM | Permalink | Comments (0) | TrackBacks (0)

Much of the work that I do involves developing applications that assist in solving engineering problems. Since I do the project management aspects of this (as well as lending a hand in the actual writing), I recently counted the number of lines of code in the largest project. (I was a bit surprised to find that it was almost 200,000, which is quite large by my organization's standards.) But what was I really trying to measure?

I was, of course, trying to measure complexity.

Everyone knows that lines of code are simply not a good way of measuring programmer productivity. It doesn't take into account the requirements of the application. (I.e. more complex applications need more lines of code, usually.) Thus, people have proposed alternatives to measuring software complexity, such as feature counts (also known as function points), and (perhaps better) testable requirements counts. Still, some have pointed out that the number of lines of code can be related to the amount that one can manage in one's mind, at a given point in time. In other words, we are not trying to measure productivity, we are trying to measure complexity.

Lines of code is really an easy metric. Just run the whole source directory through a utility like wc, and out pops a little number.

The other metrics are somewhat harder to determine. Function points have the flavour of arbitrariness about them. The number of requirements needs a requirements document (a good thing, of course), but requirements change as the project matures. The number of test cases is a very good measure for some aspects of the project, but care must be taken that there are not multiple tests for the same feature.

It would seem like lines of code (like programmer hours, or money invested) is a "cost" term. The completed features (like the number of test cases, etc) is a "benefit" term. Projects with a high benefit to cost ratio are doing well.

Perhaps either the cost term or the benefit term can be used to measure the complexity of the program. Programs with large number of features are going to be more complex. Similarly, programs with a large amount of code are also going to be complex. (That complexity may be warranted.)

(All of this assumes a reasonably-complete program. The prediction of complexity, based upon a set of requirements, is another question entirely.)

Posted by Jeff at 08:35 PM | Permalink | Comments (0) | TrackBacks (0)

Can I convince myself that a pilot's license is justified? Let me try to weigh the costs against the benefits. I will start with the benefits, because I can state what I hope to get out of it.

The quick answer is that I probably can convince myself of just about anything.

Benefits

My "local area" would become much larger. The introductory pilot's license allows one to fly single-engine aircraft under visual flight rules (VFR), i.e. good weather conditions. It would be feasible to fly to San Francisco, Los Vegas, San Diego, etc., without having to worry about traffic (and the many hours it takes to get out of LA on Friday nights). Day-trips to Catalina Island or Santa Barbara could be done on the spur of the moment.

I would gain experience with the practical application of the principles that I have studied. Fluid mechanics and thermodynamics are my specialties (at least in the engineering, non-computer science world). It makes sense that I would gain a finer appreciation of the physics of flow, if I have my hand on the controls. There was a reason I liked those subjects.

It would impress my friends. Imagine my girlfriend's response if we flew off to Santa Barbara for a romantic weekend: Flying off into the ocean-kissing sun, soaring above the seagulls, comfortable in our silver vessel but able to touch the clouds. Imagine a spur-of-the-moment trip to Vegas with my buddies: Landing in the bright lights of the desert city, jumping out of the plane, dressed to nines, ready to conquer the casinos. Imagine the flying to Mackinac Island with my family, one of our favorite vacation spots: The hours of driving left behind, the exorbitant ferry prices bypassed, the simpleness of the entire process.

Costs

The major cost involves training. This site has a very good discussion about the process. It seems like it could cost as much as $5000. The license requires a minimum of 40 hours of flight time, but ends up usually being higher (as the instructor determines when you are competent to fly), such as 60 to 80 hours. Aircraft are rented by the flight hour (not by the amount of time they are "checked out", interestingly enough), at rates like $40-$75 per hour. The instructors are an additional $15-$25.

Besides money, training costs time. There is the 80 or so hours of flight time, of course. But there is also ground instruction, in order to learn the principals of flying. If one studies full-time, it is possible complete training in two weeks. But that seems somewhat unlikely, if I want to be employed at the same time. It is suggested that part-timers have at least three sessions a week, in order to help knowledge retention. (Part-time students might take up to six months to finish training.) It might be feasible to "jump start" training by taking a week of vacation, and then finishing the second half (or so) or training part-time.

After the license is obtained, various maintenance activities have to be done. I think that a medical examination is needed every two years. Although I'm not sure, it would seem reasonable if the license would expire if not used often enough.

And plane rental fees and airport landing fees are non-negligible. Suppose I took one trip per month. Let's imagine an average trip: Two hours of flight time ($120 @ $60/hr), landing at a field with fees ($20), and two hours back ($120). That ends up to be $260 per trip, or over $3000/year.

Plan

When I imagine what I will be like in the future, I imagine that I will be able to fly planes. My income will only increase, so the costs will decrease in importance. The benefits will be life-long.

Okay. So I want to do it. What next?

I need to verify the actual cost numbers. It would make sense to do this out of the Santa Monica airport, but I should check the other local airports, too. (The Torrance airport is close to work, so that is feasible.) I should talk to some pilots that I know, to get their ideas about the process and maybe some recommendations for flight instructors.

Timing. As my roommate is moving out soon, I will need to buy some things for my home. Those purchases might be absorbed in a couple of months. Perhaps this summer, then?

Posted by Jeff at 10:05 PM | Permalink | Comments (7) | TrackBacks (0)

Today, Jeff rested. I woke up late, talked to the family in the exotic eastern lands, meandered through the halls of the Westwood Borders, and watched some basketball. Not terribly productive... almost like my mind was thousands of miles away (hopefully in some warm tropical locale).

There seems to be some problem with Intercept Vector's weather web service, which means that my little weather sidebar doesn't work properly. I tried to debug the plugin, but since it is the service's fault, it simply seems easier to sit on my butt and just wait for it to start working again.

I've also included a new sidebar, using the plug-in available from here. This plugin outputs URLs from recent posts, and I'm using it in my little sidebar.

I have some questions about Movable Type's plugin system: When does it reprocess the tags? The weather plugin, in particular, is somewhat limiting if the page needs to be reprocessed in order to get the latest weather info. I suppose that these blogs are updated frequently, which would cause a reprocessing. Maybe it is not an issue.

Posted by Jeff at 08:02 PM | Permalink | TrackBacks (0)

On Thursday after work, I went on an evening run through my neighborhood. The police had blocked off the Wilshire exit off of the 405, due to anti-war protesters, and I was curious to see what was actually going on.

The air was slightly cool, with only a hint of sea-fog blown in by the winds from Santa Monica. (Here at the Farthest West, there is always a reminder of the ocean, always a reminder of the crashing waves.) The sky had begun to turn purple, studded with the stars bright enough to survive the setting sun and Los Angeles. A good evening to stretch the legs and run, even without the potential of seeing an interesting sight.

News helicopters were in the air, diverted from their normal activity of monitoring car chases and freeway conditions. Some hovered in the sky to west of my home; some circled the area looking for a good shot, flies looking for a place to land on a carcass. (Pardon the bitterness of that analogy. Helicopters had interrupted my precious beauty sleep over the past couple of nights.)

I ran west along Wilshire, down the hill, past the sentinal office buildings of Westwood. There were some people on the sidewalks, almost less than normal, I thought. Some people were just the late-working, still in the suits and dresses, heading home after a long day in the cubicle farms. There were some people with rolled-up signs, walking to the Federal Building, where the main protest was taking place.

As I got to the corner of Veteran and Wilshire, near the center of the action, I was surprised to find that I didn't even need to slow down. There were many people, yes, but it was not shoulder-to-shoulder crowds. There were some largish banners, and I think that there was an area for speakers. It might be that I was there too early. The protesters themselves seemed to have varying enthusiasm levels. Some were just standing around, looking perhaps a bit embarrassed or amused. Others were waving signs or chanting. Many were young, perhaps UCLA students. I wondered why they got so excited about this particular war.

It appeared to have been planned well. The police barricades were in logical areas, directing traffic along side roads. There was even a medical tent set up along Veteran, south of the main protest area. As the breath pulled raggedly in and out of my lungs, my sweat-filled eyes gazed at the medical tent, and I wondered idly if they would take walk-ins that were not affiliated with the protest.

I turned west on Santa Monica Boulevard, and dodged the traffic. Westwood (heading north) was backed up with cars, and many of the normally-quiet sidestreets had commuters trying to find clever ways around the closed areas of Wilshire.

As I turned north, on Selby, near the Mormon Temple, and returned home, I thought several things.

1. It was a very pleasant night.
2. Protesting the actions of the government is simultaneously a youthful thing, and a very American thing to do.
3. I never want to be in the position of defending or supporting the mostly-evil against the mostly-good.

Posted by Jeff at 11:47 PM | Permalink | Comments (0) | TrackBacks (0)

The logs of my web-server recently showed that my site was visited by "spiders" from thunderstone, a web index service. (Spiders are automatic indexing programs that sequentially request web pages based upon links, and then sort those pages for use in search engines.) This, of course, piqued my interest in web indexing applications, such as the mighty (and ubiquitous) Google.

Google has some information about its ranking system here. They include a page in which one can enter the URL of your site, so that it will eventually be spidered through. After the crawl through the web, they analyze the links and such, and build a new index. This index is double-checked, and then rolled out to the production servers. (This rollout process is known as the "Google Dance", and seems to have spawned a whole subculture, concerned about their new rankings. See Kuro5hin, this tool for monitoring the rollout progress, and this good technical description.) This site has some good user-submitted information about Google.

I have to imagine that there are a lot of smart people working on ways of indexing the many terabyte of information out there. Google has done it better than anyone else, and seems to be able to keep up with the people who seek to fool it. Kudos.

Because of Google's importance in day-to-day web access, many people have developed a great sensitivity toward its ranking. Because of indexing algorithm strongly depends upon the number of "incoming" links to one's site, people sometimes seem to almost beg people to link to them. I find this intriguing... What kind of society does that build? I am encouraged: Sites with useful content get linked to by people who are best able to judge, and Google rewards those useful sites with higher rankings. It seems to be more than just democratic (although that is a part of it), it seems to encourage a meritocracy, the best of all possible systems.

I've toyed with submitting my site to Yahoo or Netscape's directory. I almost wonder, though: Do I really want more visitors to my site? Would I limit the content of my ramblings if I believed that a wide range of strangers was reading my stuff? Hmm... I'm not really putting anything personal on here, and nothing that I wouldn't stand up in public and proclaim. (I sometimes embed messages to specific people, and that can certainly continue. If anything, the hidden messages become more special because of public traffic.)

Posted by Jeff at 10:44 PM | Permalink | Comments (0) | TrackBacks (0)

It would not be appropriate to let this day go by without some note. America and her allies go to war.

There are a couple of good reasons NOT to go to war. First, it is expensive, and those resources could go to other causes. Second, there will be a loss of human life that should not be condoned.

On the other hand, Iraq is a dictatorship, and as the torch-bearer for freedom, we have the right to clean out slave pits. The Iraqi military has chemical and biological weapons (at least they did during the first Gulf War), and they have publically declared themselves our enemy. And even if that government doesn't use them, it will eventually collapse (as all dictatorships do) and could then fall into even worse hands. To back down would to concede moral authority to a lesser society.

The question is moot, in some sense. Tanks, missles, and bombers have the only say, now. May liberty prevail. May this be over with quickly.

Posted by Jeff at 11:27 PM | Permalink | Comments (0) | TrackBacks (0)

You might notice the weather sidebar, newly added this evening. It is based upon a Movable Type plug-in by Gavin Estey and can be downloaded from the plug-in directory. While easy to use (once I had the necessary Perl modules downloaded), it took some thought to get the index template configured correctly.

Also note the cute little icon. One of the Weather Plug-In variables contains an image-ready name, and so, if the site author (me) sets up image files, a picture can be displayed. This brings me to today's moral dilemma.

Since I am not a graphic artist, but I needed a set of weather-related images, I did what any computer hacker would do: I asked Google Images. It responded back with a number of choices, and I happened to pick one that brought me to the Indystar page. (Go Hoosiers!) They have the weather forecast, with pretty little icons depicting clouds and suns and snow and rain. And they all seemed to be stored in the same directory, filed by index number, hinting that there might be more.

So, again, like any self-respectingcomputer hacker would do, I wrote a script to iterate through a large set of numbers, and try to download the given file. This was made amazingly easy with tools such as Perl and Wget. I wrote it, it ran correctly the first time (amazingly enough), and downloaded a bunch of useful weather pictures, within about 10 minutes.

But, I have to wonder... Was what I did legal? The pictures obviously represent some level of investment, even though I'm sure that a graphic designer could have drawn them all out before breakfast. Not all of the pictures were actively displayed. (My script just stumbled on them.) Indystar would certainly not want their competitors using their images.

Still, I'm not going to beat myself up about it. I'm giving Indystar ample credit for the pictures. My site is non-commercial, and I am not competing with Indystar on anything. And, a reasonable argument might be made that the pictures are in the public domain, anyway. And, if Indystar wishes me to take the pictures down, I certainly will.

Posted by Jeff at 10:47 PM | Permalink | Comments (0) | TrackBacks (0)

My linux box, used for running this web server, as well as providing a gateway for my home LAN, has been running for 90 days! (In other words, it hasn't been shut off or rebooted.) Unfortunately, the network connection has been dropped several times, but that's Earthlink's fault.

pytheas:~$ uptime
10:04pm up 90 days, 45 min, 5 users, load average: 0.02, 0.01, 0.04

Posted by Jeff at 10:07 PM | Permalink | Comments (0) | TrackBacks (0)

The rainstorms moved out of Los Angeles this morning, and the air had the crisp coolness of the San Gabriels at 8000 ft. I took my digital camera along on my run, because I wanted to capture some pictures of my neighborhood. I am not a photog, or even a photographer, but here they are.

	This is a statue of a nude running dude, on Wilshire. I didn't take the picture from the other angle, in order to keep my site from degenerating into porn.
	The houses in my neighborhood usually have very well-kept yards. I've always admired the landscaping at this house.
	They are resurfacing one of the roads. The cool mountain-brought air started to smell like hot tar. Which is kind of pleasant, too.
	Shadows on the sidewalk. Screw you, Plato, it tells me SOMETHING.
	The internal alley of my condo complex.

Posted by Jeff at 05:24 PM | Permalink | Comments (0) | TrackBacks (0)

It is hard to find the will to run, when I am warmly buried in my bed. The slackened muscles, relaxed after a good night's sleep, do not look forward to blasting their way down Wilshire Boulevard. But, if the will can be found and I manage to strap on my running clothes, I am rewarded with a burst of happiness within the first couple of steps.

There had been several times in my life that I tried to get into the habit of running. While I was in grade school, my parents started jogging nearly everyday. (That culminated in the SportsMed 10k race in South Bend, and I can still remember watching my dad cross the finish line. I had run in the 5k race.) In college, I would sometimes run around campus or around the lakes, but it certainly didn't happen on a regular basis. (I'm not sure why I never made it into a habit... Perhaps it was the late nights, the demands of schoolwork and band, and the lack of social pressure. If nobody else is doing it, then maybe I don't have to do it either.)

It wasn't until the second year of grad school, that I really started running regularly. I lived alone, so it was easier to indulge in weird activities. Austin has many great running paths, including a 10-mile course around Town Lake, in the center of town. It became serious when I signed up to run the Austin Motorola Marathon, with my friend Karen Shopoff. We joined a training group that met every weekend by Town Lake, and that provided some structure to the effort. (The subtle interplay of rivalry, self-induced motivation, sexual tension, and group pressure is a wonderful thing to behold, if it is helping you become better.)

The Austin marathon is a story better told elsewhere. I finished it, and finished well. (Starting was a separate problem.)

Since moving to Los Angeles, my running has become a bit erratic. There were several intervals in which I ran very regularly, such as when I was training for the LA Marathon. There have been other times in which I would go weeks without slapping the pavement. My mileage can almost certainly be correlated with life-changes. (I.e. plot "week number" on the x-axis of a graph, with "miles ran" on the y. The graph probably looks like a square wave. Interpose events, such as dates, project milestones at work, moving, family events, etc, as vertical lines. I image that the vertical lines are fairly close to the edges of the square wave.)

I had originally conceived of this post as a description of the joys of running: The sweetness of the cool air as it is pulled into one's ragged lungs, the stretched tautness of legs muscles, the sweat of exertion covering one's face even in the cold air, the tired pleasure of much-needed shower afterwards. Perhaps that too is a story for another time.

But, as this post has been more about my running history, I shall conclude by asking myself: How shall my running go now? Should I set a goal (Chicago Marathon, perhaps), and work towards that? How can I build up the endurance and stamina that is needed? What kinds of motivations can I use to force myself to still get up and run, even in moments of weakness?

Posted by Jeff at 05:01 PM | Permalink | Comments (0) | TrackBacks (0)

I happened across a web site dedicated to haikus about elements, organized like the periodic table. The site is located here, but I shall quote "carbon" (by Stephanie Hall).

Dead stars reborn
as diamonds, buckeyballs,
and beings

Posted by Jeff at 11:11 AM | Permalink | Comments (0) | TrackBacks (0)

The common problem of sending private messages through a public channel is surprisingly difficult, and a fruitful area of research.

Throughout history, entities from major governments to private personages have sought to protect their lines of communication. Their efforts seem to have fallen into several categories:

1. Develop a private means of transmission. ("Private" is relative to the attacker's resources.) An example would be the use special couriers to take the message from one party to the other. The addition of a courier brings another party into the picture, and many messages have been compromised by the courier failing in his duties. With the technological advances in the 20th century, such as radio broadcasting, as well as the specialization of labor (inexpensive public networks maintained by profit-seeking companies), it is increasingly difficult to NOT make use of the available public communication networks. Because private communication lines are so easily compromised (if the attacker is sophisticated), and because public networks are so inexpensive, it makes sense to investigate other forms of ensuring privacy.
2. Use an algorithm to encrypt data, transmitted over a public channel. A sender and receiver agree upon some means of encrypting the data, such as via one-time pads, or secret keys and public algorithms. This is perhaps the most widely used approach. Publicly-available algorithms, such as the Advanced Encryption Standard (AES, formerly know as Rijndael), are usually researched by a large community of analysts, and strengths and weaknesses are well-known. This ensures the quality of the algorithm, leaving the secrecy of the message to depend upon the secrecy of the keys or passwords. Many governments and militaries use secret algorithms, to provide another layer of safety. (This approach implies that those entities have enough in-house experts to ensure that the algorithms are safe. History is filled with stories of groups that depended upon a secret but easily-crackable algorithm.) Still, encryption algorithms reveal that SOME SORT of secret message has been passed. Also, encryption means that secret keys must be passed between the two parties. The secrecy of the keys seems to be the weakest link.
3. Hide the secret message in seemingly-innocuous data. Perhaps the most common approach to this is to reference mutual experiences within normal text. This only works, of course, when the sender and receiver actually HAVE mutual experiences that are relatively unknown to others. An approach known as "steganography" modifies image data, so that the picture looks the same, but a message can be extracted. (There have been rumors that terrorists have communicated by modifying bits of pornographic pictures, and then posting those pictures on USENET. As far as I know, those rumors have never been validated.) This approach differs from the second concept (encryption) by the fact that the sender and receiver might not have to agree upon an algorithm ahead of time, and that it is possible that attackers might simply ignore the message due to its innocent character.

If I had to evaluate those three options, I would say that the first method is simplest conceptually (when the attacker is not sophisticated), that second method (encryption algorithms) is the most secure in the general case, while the third method (hiding secret messages within innocuous text) is the most fun.

Posted by Jeff at 12:21 AM | Permalink | Comments (0) | TrackBacks (0)

Today was a pretty good day.

The physical effects are amazing, really, when things go well. One suddenly has some extra energy, almost enough to have to burn it off by running around the block. Things taste better, too. (Yummy things, at least.) Somehow, even my carped-out thumbs feel better.

Posted by Jeff at 11:16 PM | Permalink | Comments (1) | TrackBacks (0)

Beware the mouse. It looks harmless. But it has no loyalty: After working with it for hours on end, you might notice that it has stolen the strength from your wrists.

Let us examine the facts. I have been working long hours, due to commitments at my job. And, I think that I have been messing around with my computer here at home more than usual, too. (Last night's failed attempt to get my digital camera to work with linux is a case in point.) In the last month at work, I had installed a new trackball mouse. (The trackball is operated by the thumb, and I got it because I feared that my wrists were getting sore.) Now my wrists and thumbs feel sore.

And there are interesting problems to solve. I need to upgrade my server kernel. My webserver had gone done at about 9am this morning, due to a drop in the ISP connection, so I need to write some code to help make it more resilient to those kinds of problems. I am thinking about kicking off a big effort at refactoring our database code at work.

Maybe I need a new hobby.

Or, better yet, if they (who?) can come up with a better human-computer interface. Yeah, that's it. Something that doesn't require one to move fingers in a repetitive way. Eye-ball tracking? Brain-wave sensing?

Posted by Jeff at 10:17 PM | Permalink | Comments (0) | TrackBacks (0)

I had worked late today, putting the final touches on a clever solution to a difficult problem. As I sped up the 405 on my way home (fatigued from my work and pleased with my success) I turned the radio to the classical station, KUSC, to find some music to suit my mood. As luck would have it, they were playing "Lincolnshire Posy" by Percy Aldridge Grainger. I had played that music while I was in the Notre Dame Concert Band, and it brought back good memories.

One particular memory was almost overwhelming. It was senior year, on the last concert of the week (spring break). I think that we were in Pennsylvania or Ohio or somewhere. (There is no better way of getting to know a group of people very well, than to spent 24 hours a day with them, surrounded by strangers and strange places. But that is a moot point, as I had spent nearly four years with these people.) Our show started in two hours, but everyone was in their concert attire. The guys wore tuxes, and women wore black skirts and white shirts. We had finished setting up the stage (on the altar of an old Catholic church), and everyone was relaxing, laughing at our inside jokes, and talking about minor things.

It is amazing how well I remember that particular moment. I can taste my saxophone reed, I can smell the hair of that dark-haired girl standing so close to me (an amazing surprise that trip), I can see the sunbeams shining through the dust drifting off the rafters, I can hear the murmuring and laughter of my friends.

At this point, I need to get Aristotelian on my head. Strong memories of pleasant times are good in the proper amounts: They can remind you of the joy that is possible, and can be like a buoy in the rough waters of difficult times. But one can have too much of it... The past is gone, and dwelling on those events can cause one to miss the pleasures of the present and future.

That said, I salute some excellent memories: my old friends, some lyrical music, a good day somewhere in the Midwest, and my past self.

Posted by Jeff at 10:35 PM | Permalink | Comments (2) | TrackBacks (0)

I have decided to study the effects of repeated high-momentum impacts on the bones in my pelvis and lower back. My cousin, Rob, has graciously introduced me to a wonderful laboratory for those experiments, at Mammoth Mountain Ski/Snowboard Resort in central California.

Rob is my cousin, on my mother's side of the family. Since the Lisenko/Przybylski/Wrobleski/Borlik clan, though as numerous as grains of sand, mostly resides in the metropolis of South Bend, Indiana, Rob and I were somewhat unfamiliar with real mountains until moving to California. Now, perhaps due to the avid winter-sports enthusiasts that Rob works with, he has become quite enchanted with the snowboard.

Mammoth is a great place to learn how to snowboard, assuming that one is willing to pay the price. (And the price is hefty: in required driving time, in physical discomfort, and of course, in financial terms.) I had taken a introductory class last year, which lasted about half of a day, and found the instruction to be helpful in getting started. Nothing compares to practical experience, though, and Mammoth offered a number of quality beginner slopes.

This year, we drove up during the first weekend of February. The weather was pleasant, and the slopes had plenty of snow. The slopes were somewhat icy the first day (Saturday), but snow fell that evening, so there was some powder on Sunday morning. I stayed mostly on beginner (green) slopes, to improve my technique.

I am quite comfortable riding on the backside edge of the board, and am even willing to point the board downhill, to build up a nice dark head of velocity. But, I still don't have a lot of control when riding on the toe-side edge of the board, which greatly reduces the amount that I can do. I cannot slalom downhill, and have to use the "falling leaf" technique to get downhill under control. Still, I am pleased with my advancement in just two trips to that mountain.

I was amazed at the number of people at Mammoth, and at the number of people that are GOOD. Learning how to ski or snowboard takes time, effort, and equipment, which means: Free time and money. Are there really that many people out there with the time and money to pursue such a hobby? How do they manage to get to that level without causing serious bodily injury?

It is a heart-thumping thrill to fly down the mountain, though. Quick reflexes, concentration, training, and stamina are all required... It is fulfilling to meld mind and body together, to meet a challenge.

Posted by Jeff at 09:48 PM | Permalink | TrackBacks (0)

I need to relate one of my annoyances. My webserver is constantly attacked by "script-kiddies", who seek to exploit various IIS security holes. Listen closely, children: I DON'T RUN WINDOWS! Those exploits just fill up my access logs with error 404s. I do have their IP addresses (including reverse nameserver results), so I could inform their ISP's of this rude (and possibly dangerous) behavior.

So the apache logs get filled up with crap. No big deal. All I really need to do is have a script that cleans my logs of anything that includes "winnt/system32" (with status 404).

I do have to wonder if the nominal owners of the machines even realize that they are sending out those kinds of requests. Out of curiousity, I've looked around some of those who are attacking my machine, and some of them are old Windows 98 boxes. Since that operating system is so insecure, it might have been compromised.

I am also surprised at the number of ports that Windows machine have open. A friend of mine has a fairly new XP installation, and nmap returns

Port       State       Service

80/tcp     open        http

135/tcp    open        loc-srv

139/tcp    open        netbios-ssn

445/tcp    open        microsoft-ds

641/tcp    open        unknown

1025/tcp   open        NFS-or-IIS

5000/tcp   open        UPnP

What does such lack of security mean for the overall system? As more and more people use always-on broadband connections, and those nodes have security holes, it should become easier to cause major problems via viruses / etc.

Posted by Jeff at 09:25 PM | Permalink | Comments (0) | TrackBacks (0)

While browsing around the web today, I happened across some Keirsey personality testers. These should probably be taken with a grain of salt, of course, as there are more than 16 types of personalities out there in the world.

According to these tests, I am either an "INTJ" or an "INTP". The various descriptions of these categories seem about right.

I took three web-based personality tests.

The first was at the bloginality site. The number of questions was small, and very generic. It told me that I was a an "INTJ", but I was somewhat unsatisified with this, due to the "low resolution" of the questions.

The second test was at the advisorteam site, and consisted of about 70 questions. That site required a registration, and asked some current events questions afterwards. Furthermore, they didn't output the full results of the test. (Pay $15, and let someone tell you who you are.) They did say that I was a "Rational", i.e. someone with an "NT" group. No, really?

The third, and IMHO best, was at the humanmetrics site. This was also a 70 question test. There was much more interesting output, including a ranking of how "expressed" (in the genetics way) I am in each category. Results:

• moderately expressed introvert (28%)
• distinctively expressed intuitive personality (67%)
• very expressed thinking personality (78%)
• moderately expressed judging personality (33%)

That apparently means that I am a strong Rational (NT), but somewhere between an introvert and an extrovert (I and E), and somewhere between "judging" and "perceiving" (J and P). I don't know about the "extrovert" part... Most of my social interactions are with a group of close friends.

The INTJ type is known as "Mastermind". Some descriptions of that personality type are here and here. I think that I would like to be more like this.

The INTP type is also called the "Architect" type. Some descriptions are here and (more favorably) here. The second link even as a reference to Ayn Rand!

Anyway, in the words of Popeye (or to paraphrase the Judeo-Christian god) "I am who I am". And I am satisifed with the Rational label, especially since many of the historical personages that I admire are of the same type.

Posted by Jeff at 02:35 PM | Permalink | Comments (0) | TrackBacks (0)

I took this picture of my mom and dad this past Christmas, in Granger, Indiana. They wanted a picture to put as their login icon for their new computer. (Pardon the poor photography.)

Posted by Jeff at 09:19 PM | Permalink | TrackBacks (0)

At lunchtime, we emerged from our cubicles, to squint at the warm
southern Californian sun and rest our carped-out hands. About
eight can sit at the picnic table, outside of the Heat Transfer
manufacturing building, and the table was filled with the younger
members of the analysis group.

For a bunch of analysts, lunchtime conversation is remarkable
normal (for highly educated and yet somewhat introverted people).
Usually, there is some talk of sports, or cars, or movies, or
amusing gossip about our coworkers. Indeed, most of us want to
avoid or quickly squelch work-talk (much as leaks in a dam should
be patched immediately).

The normalcy of our lunchtime conversations is not the point of
this little essay. Quite the opposite, really. We are all
engineers (and even worse: analysts), so we the topic of the
lunchtime conversation naturally turned to science.

Someone mentioned that a recent paper from the national lab in
Los Alamos suggested that the carbon dating process has some
inherent errors. The argument was that pressure (or
other environmental factors) plays a large role in the decay of
Carbon-12. The implication was that many of the carbon-dated
relics are actually much younger than previously thought.

So how should one respond to that idea?

We talked a bit about the implications: Estimates of growth
rates and evolutionary progress rates would have to be increased
some. Several coworkers were pleased to see the world of science
shaken up a bit... Some controversy is good for challenging the
establishment.

But for the most part, we said "bullshit". Read the paper itself,
wait for more data, and wait to see if the experiments can be
duplicated. It is an interesting thought, and certainly worth
considering. But it doesn't really fit in with the rest of the
established techniques: There are other ways of measuring the age
of an object, and those techniques need to synch up with the
revisions to the carbon-12 methods.

There seems to be a couple of rules when hearing about new ideas:

• Be skeptical but open. Don't reject it immediately, but
  don't accept it unprocessed either. Letting the idea roll
  around in one's head for a while is a good thing. (Not to imply
  empty heads...)
• Make decisions based upon data. Argument by authority is
  never a good enough reason. (Some would say the the whole
  scientific method is just a hack to prevent "authorities" from
  having the final say.)
• Ensure new facts are consistent with the rest of your knowledge.
  The universe might be a puzzle, but that only means that the
  pieces have to fit.

I guess that those rules are just common sense, and hardly worth
the trouble to write down. (But how often are they followed? How
much garbage is swallowed raw by people unwilling to think for
themselves?)

A friend of mine once suggested that making decisions in the face
of uncertainty should be like leading an army. Make your best
guess (and have the army march in that direction), but send scouts
out along other paths. If a scout finds something promising,
continue to send more men that way. If it turns out right, then
the whole army will soon be streaming in the new direction.

Maybe our lunchtime conversation was not explicitly about
thermodynamics or system design. But, we are trained to be
skeptical in technical matters, and it is interesting to see our
training kick in, under different circumstances.

Posted by Jeff at 10:57 PM | Permalink | Comments (0) | TrackBacks (0)

Last year, I spent about about a month in England, mostly on business. That was the first time that I had been abroad, and really the first time that I spent significant time in any country other than the United States.

This is one picture from that trip, taken on Friday, September 6, 2002. The location is Barton Bradstock, a small town about 20 miles south of Yeovil, on the English Channel, in Somerset. The wind and waves complemented the young hiking lady that I met upon the path. I had hoped to hike further along the coast that day. Unfortunately, the drive had taken much longer than I had expected. Twenty miles along LA's 405 freeway can zip by, while twenty miles through hedge-rows and single-lane villages requires much more effort! Next time, I will plan ahead and make a day of it. Still, dinner in a local pub was excellent. The service was excellent, and all three of the waitresses seemed to take turns inquiring about my meal. Perhaps it was a local custom. Or maybe they just wanted to hear a midwestern-US accent. In all, though, I felt welcome throughout the areas I traveled in England.

This picture shows the view from my room in the King's Arms inn, in the village of Montecute. The town of Yeovil is surrounded by small villages, including Montecute. These villages seem to be ageless (in the sense that they are old beyond counting): A shock to the boy who grew up in a fast-growing area of Indiana and lives in Los Angeles! Montecute House, basically across the street from the King's Arms, was a stately manor from the 16th century. Montecutus, the hill immediately behind the inn, was the site of a Roman garrison. The countryside has seem human inhabitants for many centuries, and seen mankind rise from simple hunter-gatherers to the complex mostly-scientific society we have now. (Where next, brothers? What land will we make our own? Will we change as much as we have since our feet first trod the mud of merry old England?)

I may post more about that trip, as I have many pictures. (London, in particular, begs for text and pictures.) This trip whetted my appetite for traveling, and I hope to soon share more stories.

Posted by Jeff at 09:57 PM | Permalink | Comments (0) | TrackBacks (0)

It is late Sunday night, and here I am hacking away. Why am I doing this? There are several reasons:

• Personal development. I would like to improve the quality of my writing, and the best way to do that seems to be to THINK and WRITE. Improvements to the quality of writing hopefully lead to improvements in the quality of thought.
• Historical archiving. Someday I might wonder "What the hell was I thinking?", and maybe this will provide an answer. Future Jeff, hail and well met.
• Moveable Type seems to be a well-writing piece of code. I look forward to breaking it.
• There seems to be a "blog" community, and maybe I could play a part in it.
• I like hacking away at computer programs. That is a sufficient reason.

So here we are. I've never been very good at keeping diaries. (I'm not even very good at taking notes.) Let's see where it goes, but I doubt that I will actually write very much. Let's just see where it goes.

Posted by Jeff at 11:48 PM | Permalink | TrackBacks (0)