Saturday, October 29, 2011

Big milestone for the new Bay Bridge

This week, a major milestone in the construction of the new Bay Bridge: the last section of deck for the suspension segment is now in place. I like this article in the Contra Costa Times because it does a good job of explaining what's going on, and has some nice pictures of the Left Coast Lifter in action. As the CCTimes article notes:
The deck piece installed Friday is key.

"It's the place where the cable actually comes in and locks into the bridge," Caltrans spokesman Bart Ney said.

"It's self-anchored. That means the cable doesn't go into the ground, but into this piece. There's a big hole in the deck where will the cable will go down and anchor into this section."

Unlike the Golden Gate Bridge, where cables were strung before the deck was installed, the new Bay Bridge suspension span requires that the deck be installed before the cable. Temporary supports hold up the deck until the cable is tensioned.

I guess that means that the Lifter is likely to move on now ... is there another bridge somewhere on the planet awaiting its services? Check out this great picture of the Lifter setting that massive piece of roadway into the final slot just as easy as pie!

Here's a pretty computer-generated video showing what it will (soon) look like.

Next step: string the cables! I believe that starts in earnest after Thanksgiving. It should be something to see; if you look carefully at the various pictures, you can see the catwalks that the crew will walk during cable installation.

Wednesday, October 26, 2011

KFOG Live from the Archive -- online or in the store?

The Peet's Coffee website wants $8 for shipping the KFOG Live from the Archives CD.

For that, it's worth waiting until Tuesday and walking 2 blocks down to the Peets to get my copy.

And maybe get a cup of coffee, too :)

Derby 10.8.2.2 is released

A new maintenance release of Derby has been released, with the typical collection of bug fixes and small features.

What was more interesting about this release was the way that the community handled the decision-making surrounding a relatively minor performance feature: concurrent generation of new values for identity columns.

The feature went through the typical Derby development cycle: a developer, interested in the problem, created a proposal for fixing it; the patch was reviewed and discussed; feedback was addressed; the patch was committed.

Somewhat later, near the point when it was ready to be released, other developers in the community were running certain complex test suites that aren't routinely run, and these test suites were not performing well.

It wasn't obvious what was causing the test suites to mis-behave. When test suites get sufficiently complicated, diagnosing their behaviors can be as hard or harder than diagnosing the behavior of the actual product. We have lots of practice diagnosing the behaviors of the main product code, and over time we've built all sorts of debugging and diagnosis hooks into that code to assist with analysis. But tests generally are rather leaner in this area, and it's hard to tell what's going on when a complex, unfamiliar, and rarely-run test fails: is there a real problem in the product? Or is this a weak test, which was accidentally passing in the past because it wasn't written quite carefully enough?

The Derby community responded very well to these challenges, I feel.

There was no rush to judgement, no finger-pointing, no blaming. Instead, different members of the community studied the new behaviors, constructed theories, ran experiments, offered suggestions, and considered the ideas of others.

As time passed, the first release candidate missed its schedule, then was withdrawn from consideration. The suspect feature was backed out from the codeline, and testing continued. It was very hard to tell: was the new behavior more stable? Or about the same?

After considerable time, the product was felt to be ready for release, and the second release candidate was released this week.

Even though I had only a minor part in this process, I was fascinated to be involved. At a Derby community luncheon during the Oracle Java conference earlier this month, I attempted to sum up my observations about what had occurred to the group at large as follows:

  • Software is hard
  • We made a change
  • Something new and interesting happened in the software
  • We talked about it as a community
  • Lots of people learned new things about the software
  • We addressed the problem, and moved on

I know that it was quite painful for some of the participants who were more closely involved in the effort, but from my point of view, this was software engineering at its finest: a team of dedicated and talented people collaborate on an extremely complex undertaking and, together, overcome obstacles and deliver a strong new release.

Congratulations Derby on Derby 10.8.2.2!

Tuesday, October 25, 2011

Ubuntu 11.10 nits

Since upgrading my Dell Latitude D610 to Ubuntu 11.10, two nits:
  1. My computer seems to drop the wireless connection, and the only way to restart it is to reboot. Without warning, the system is suddenly offline, and fiddling with the Network widgets doesn't bring it back online. ifconfig down/up doesn't bring it back online, either. But rebooting it gets me back online with 100% reliability
  2. The screen dims when the computer is idle for a certain period of time. Then, after waking it back up from screen-dim, the screen lights up, but then slowly darkens again to an almost-dim state. If I then go into the Displays control panel and fiddle with the screen resolution (e.g., set it to a different resolution but then revert to the current resolution), the screen becomes bright again.

I'm not sure what's causing either of these problems, and I'm not sure how to diagnose them further. For the time being, Ubuntu 11.10 on this computer is a bit of an annoyance.

Oh, by the way, 3 other computers that I've got which are running 11.10 are not displaying these symptoms. Just this one.

Monday, October 24, 2011

Hot Wheels!

Mmmm... Hot Wheels ... I love Hot Wheels! So I completely loved this video.

The analysis of the track seems pretty reasonable to me; I think the killer question is the cost. Those booster motors aren't cheap!

I wonder if the author of the video has some special access, like he maybe works for Mattel's marketing department or something like that.

I had a childhood friend whose father worked for Mattel (he was a car designer/artist). So it's possible :)

Another possibility is that the video was spliced together out of multiple shots, and the person making the video only had to have enough track supplies for any single shot. That would make the overall resource consumption more reasonable, since no single shot had an unreasonable amount of track/turns/loops/boosters in it.

I wish the video had had more shots of the kids admiring the car running around the track. The first scene was great!

I thought the single least-likely part of the video was where the car jumped into that funnel-like thing and then got going again on the track. I suspect that particular part of the video took multiple shots...

Saturday, October 22, 2011

Mojave Air and Space Port

Here's a great photo-essay on the Mojave Air and Space Port. I used to pass this pretty routinely in the 1990's, when I would go visit my parents in Ridgecrest.

It's been 20 years now, but the memories are still strong, and this nice short photo-essay was fun to browse through.

Friday, October 21, 2011

Personal Bests

It is no secret that my two favorite writers in The New Yorker are (in either order): Atul Gawande, and Adam Gopnik. So it was with some pleasure that I noticed that two recent issues featured articles from them: Personal Best, by Gawande, and Broken Kingdom, by Gopnik. Each essay is different, and their topics are completely unrelated, yet I find them intriguingly inter-connected.

Gopnik's article celebrates the fiftieth anniversary of a very under-appreciated classic: Norton Juster's The Phantom Tollbooth (published the year I was born!). As Gopnik says, it really means something when a children's book stands the test of time like this:

it means that the book hasn't been passed just from parent to child but from parent to child and on to child again.

Somehow, Gopnik tracks down not just Juster, but also Jules Feiffer, the illustrator, and spends several hours with them ("a pair of wryly benevolent uncles") talking about the book, about how it came to be, and about what they think it means that it has survived to the present day: "The book is made magical by Juster's and Feiffer's gift for transforming abstract philosophical ideas into unforgettable images."

Gopnik proposes that the "enduring magic" of The Phantom Tollbooth is in fact quite fundamental:

As with every classic of children's literature, its real subject is education. The distinctive quality of modern civilization, after all, is that children are subjected to year after year after year of schooling. In the best-loved kids' books, the choice is often between the true education presented in the book -- say, Arthur's through anaimals at the hands of Merlyn, in The Sword in the Stone -- and the false education of the world and school. The child being read to (and the adult reading) is persuaded that self-reliance is a better model for learning than slavish obedience.

The Phantom Tollbooth, claims Gopnik, represents the ultimate paean to curiosity and a love of all knowledge, wherever it might lie. It is:

not just a manifesto for learning; it is a manifesto for the liberal arts, for a liberal education, and even for the liberal-arts college.

Meanwhile, Gawande is thinking about learning, too, but from a quite different angle:

I've been a surgeon for eight years. For the past couple of them, my performance in the operating room has reached a plateau. I'd like to think it's a good thing -- I've arrived at my professional peak. But mainly it seems as if I've just stopped getting better.

Not surprisingly, this worries Gawande, and he tries various techniques to figure out what is wrong, but then inspiration arrives from a somewhat unlikely corner; while at a medical conference, he takes a break to practice his tennis, and works out with the club's "house pro". Afterwards he happens to be watching a tennis match, and:

I watched Rafael Nadal play a tournament match on the Tennis Channel. The camera flashed to his coach, and the obvious struck me as interesting: even Rafael Nadal has a coach. Nearly every elite tennis player in the world does. Professional athletes use coaches to make sure they are as good as they can be.

But doctors don't. I'd paid to have a kid just out of college look at my serve. So why did I find it inconceivable to pay someone to come into my operating room and coach me on my surgical technique?

The wonderful thing about Gawande, the reason that he is so incredibly inspirational and motivational, is that he doesn't just stop with this insight, he acts upon it:

I decided to try a coach. I called Robert Osteen, a retired general surgeon, whom I trained under during my residency, to see if he might consider the idea. He's one of the surgeons I most hoped to emulate in my career. His operations were swift without seeming hurried and elegant without seeming showy. He was calm. I never once saw him lose his temper. He had a plan for every circumstance. He had impeccable judgement. nad his patients has unusally few complications.

Sounds like the dream coach!

Osteen agrees to the request, and the coaching begins:

He came to my operating room one morning and stood silently observing from a step stool set back a few feet from the table. He scribbled in a notepad and changed position once in a while, looking over the anesthesia drape or watching from behind me.

Afterward, Gawande worries that it was all a waste of time:

The case went beautifully. The cancer had not spread beyond the thyroid, and, in eighty-six minutes, we removed the fleshy, butterfly-shaped organ, carefully detaching it from the trachea and from the nerves to the vocal cords. Osteen had rarely done this operation when he was practicing, and I wondered whether he would find anything useful to tell me.

Gawande need not have worried:

I'd positioned and draped the patient perfectly for me [...] but not for anyone else. [...] At one point, we found ourselves struggling to see [...] I should have made more room [...] my right elbow rose to the level of my shoulder [...] I operate with magnifying loupes and wasn't aware how much this restricted my peripheral vision [...] the operating light drifted out of the wound.
In fact, there are plenty of opportunities for improvement:
That one twenty-minute discussion gave me more to consider and work on that I'd had in the past five years.
How wonderful!

They repeat the process, multiple times, verifying that earlier mistakes are corrected, and moving on to other areas for improvement. Gawande is thrilled:

Since I have taken on a coach, my complication rate has gone down. It's too soon to know for sure whther that's not random, but it seems real. I know that I'm learning again. I can't say that every surgeon needs a coach to do his or her best work, but I've discovered that I do.

Oh, how deeply that one sentence resonates with me: "I know that I'm learning again." Is there any sensation more wonderful? Perhaps there are one or two, but this is near to the pinnacle of what it means to be a human. Will Gawande's observations lead others to find coaches? In my own field of software engineering, one of the big breakthroughs of this century is something called "Peer programming", in which engineers are challenged to work side-by-side, thinking out loud, sharing observations and ideas, listening and learning from each other constantly. It's fatiguing, but oh-so-helpful: when I get stuck, the first thing I do is call over my cube wall:

Hey Cal, are you there? Can you come be another pair of eyes? I'm just not seeing this...

And now we come full circle, back to Gopnick and Norton Juster. Thinking and thinking about The Phantom Tollbooth, Gopnik finally zeroes in on the specific insight that the book conveys, the reason that, fifty years later, it still thrills reader after reader.

"Many of the things I'm supposed to know seem so useless that I can't see the purpose in learning them at all," Milo complains to Rhyme and Reason. They don't tell him to listen to his inner spirit, or trust the Force. Instead, Reason says, "You may not see it now, but whatever we learn has a purpose and whatever we do affects everything and everyone else. ... Whenever you learn something new, the whole world becomes that much richer."

Indeed, says Gopnik:

Learning isn't a set of things that we know but a world that we enter.

Oh, dear reader: write that down and place it somewhere important, and look at it every day.