Category Archives: Technology

Thermal Snap in the City of Angels

I am sharing my story to shed light on a little-known phenomenum that we have dubbed “Thermal Snap” Why? Because it sounds a lot cooler than “Thermal Expansion of Toughened Glass.” And it could result in damage that may not meet your auto insurance deductible, and you’ll have to pay for it yourself.

CT_shattered_glass

The following interchange tries to make sense of what happened :

 

 

Last week, I left my car parked at the Metro station in the full sun. Upon my return 10 hours later, I found the back window completely shattered. Did I get hit by a meteor or a large bird? I looked around but I could not find a point of impact or a large object that could have caused the damage *to the window only* The rest of the car was undamaged.
The cops that came to fill out a report said that it was “blown out” from the pressure building inside the passenger compartment, and that they see this type of thing all the time. I had never heard of it.

When I closed the front door of the car, the vibration brought the window down in a shower of small glass fragments; it had been staying in place held together by friction between the pieces.
Bottom line: if you’re parked in the sun, leave one of your windows ever so slighty cracked down so that there is an air space to allow pressure to equialize with the outside.
The good news (if any) is that the window replacement people come to your house and the replacement cost is not much higher than what I paid back in the 90’s for a similar service.
===================== Bladerunner

Thank you, this is exactly the kind of information CT agents need in the field. I will pass this along to others, along with the proper way to tie your shoes, which has yet to fail me.

I do have a few questions:
Was your sun shade up?
Was there any external shade at any point in the day (tree, building, etc)?
Was your A/C vent open?
How many people did you flip off on your way through the parking lot?
Glad you are OK, and that the window shattered when you closed the door, and not while on the freeway. Still a huge pain :-(

Thanks,
=====================Archangel

All seriousness aside, I find it difficult to believe that your vehicle is sufficiently airtight to cause that kind of damage. That would take some serious big time air pressure. Most car cabins are not fully sealed – check the bottoms and backs of the doors. Even if fully sealed, the weatherstripping is just soft rubber and cannot contain any significant pressure. Nor can the air valves in the ventilation system.
More likely I would think is thermal stress due to expansion in the sun.
Or the car was infected by ebola.
=====================Avatar

I agree with Avatar. I believe after a 6 month failure mode analysis that “Thermal Snap” will be found to be the most likely cause. This is the technical term for what Avatar was referring to when he said ‘thermal stress due to expansion in the sun’
The glass frame and gaskets of cars are supposed to be designed to prevent/minimize this phenomenon. Thermal Snap, as all CT members know, is where the expansion of a planar object such as solar panel or windshield will heat-up but the mounting sticks and does not allow it to slide along the edges to expand, until after a certain amount of build-up pressure the glass suddenly unsticks and “snaps” to its expanded size. If this occurs while you are in the car (on earth) you will hear a loud sharp snap [as was previously observed by Agent Aquaman on a mission somewhere in the deserts of the SW]. Thus the name “Thermal Snap”.
Feel free to add this to the subject posting. This posting will surely be copied for the Society of Mechanical Engineers monthly magazine or perhaps a PHD thesis at MIT.
Adventure and Integrity
=====================Agent Aquaman

Yeah, once or twice I have seen this, where a rear
window has crumbled into postage stamp sized
pieces. And I figure it’s thermal expansion, too,
happening on a hot day, and the outward
movement of the pieces just might be due to the
window being somewhat concave, and outward
is the way to relieve pressure.

I checked with Uncle Cecil at The Straight Dope,
but came up somewhat empty, hardly worth it:  http://boards.straightdope.com/sdmb/archive/index.php/t-618261.html

This seems better:
http://en.wikipedia.org/wiki/Spontaneous_glass_breakage

The Crack.

Is Back.
=====================Agent Renegade OUT.

Our police forces are well trained in the use of military-grade weaponry and crowd-pacification techniques (and I for one, am glad for this protection) but they may not have had the scientific training of CT operatives. I’ll accept the thermal expansion or “thermal snap” as a more likely solution than air pressure.
Therefore, leaving an air space will be totally useless and we are still at the mercy of the elements.

By the way, the window shades (reflective silver) were deployed when this happened, as was a secondary set of grey shades on the side. It sounds like none of this would have made a difference. Good to know. Our best solution is to park in the shade.
===================== Bladerunner

I’m tellin ya, it’s ebola.
=====================Avatar

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Steve Jobs 1955-2011; too soon for jokes?

Logo created by a Hong Kong student. Click for more information.

It’s true, I never was a big Apple fan. I got my kids iPods because they relentlessly kept on asking. Oh, and the players were free when I signed up for a bank account (back in the day).

I inherited the old iPods and am using one today. They are not bad devices: easy to use and pretty to look at. But they are overpriced and I hate having to use iTunes to access my music. I hate being sold new material at every turn. I would love to have a simple drag-and-drop interface.

Sure there were MP3s before the iPod. I don’t blame Steve Jobs for making lossy music palatable. But I don’t share in the global outporing of grief that’s on every TV, computer and iPlatform in the world, either.

And Steve Jobs has a family that’s going thru the grieving process. So why start these tasteless Steve Jobs jokes? We may as well ask why we climb Mt. Everest. It’s because we can.

And you have to admit that it takes talent to make a clever joke about a sad, troubling situation. Sort-of like those improvisation shows where a performer is asked to make a joke about starving Somalians. A very poor-taste request, but also a challenge.

So here’s some jokes about the death of the iconic founder of Apple and the creator of the greatest devices in the world:

  • I hear President Obama has been implicated in the passing of the iconic Apple founder…
    his economic policies killed jobs.

 

  • Steve Jobs’ funeral will feature a private viewing for his many fans.
    As each person passes in front of the casket, they’ll pay 99 cents.

Nobel Prize Update

You may remember the story of our hapless Nobel Prize Hero, Doug Prasher. He lost his job in science and ended up driving a courtesy van at a Toyota dealership, but his research allowed others to win the Nobel Prize in 2008.  Things are looking up for him, we are glad to report. You can read about it here, starting with this excerpt:

 

After joining the Toyota dealership, Prasher applied for a couple of science-related jobs in Huntsville, but nothing worked out. On one occasion he had an encouraging meeting with the hiring manager at a local company working on microfluidics; when the interviewer learned that Prasher drove a courtesy van, his interest cooled. There is no way to know how many other potential researchers were driven from their studies for similar reasons, or how many potential discoveries were never made because of the psychological and practical difficulties of the scientific lifestyle.

Finally in June 2010, several weeks after my visit, Prasher’s luck changed. He e-mailed me to say he’d been offered a science job at Streamline Automation, a local research and development company. Staffed by about 20 people, the company does work for NASA, the National Science Foundation, and the U.S. Department of Defense. Prasher’s first task when he started in late June was to help develop technology to sense toxic industrial gases.

He began cautiously. “There was none of the tremendous relief you might expect,” he says. “I had been so discouraged over the years that my attitude was, this may work out and it may not.” Gradually he settled into the job. At home he occasionally took science reading to bed, something he hadn’t done in years. “A lot of the hangdog is gone,” Gina told me. 
In December Prasher won a six-month, $70,000 grant from the Department of Defense to develop a field technique for categorizing tick specimens according to their mitochondrial genes, in hopes of limiting the diseases a doctor might diagnose. It brought a sense of accomplishment that had been missing from his life for a long time. In January he told me that the cloud of depression he had lived under for years was finally lifting. Science gave him a sense of purpose.

Has Someone Stolen Your Light?

Roger Ebert has been railing against 3D movies because, amongst other things, you’re only getting half the light on the screen. And in some situations, it can be 85% darker. Now he’s discovered that it’s bleeding over into 2D films as well. The primary culprit is Sony (big surprise), who has built a popular 3D-ready digital projector with an interchangeable lens system.1 You have to change the lens to go from 2D to 3D and vice versa, and thy have made this a complex process that requires more skill than your average projectionist has. It’s so complex and time consuming that even Sony Studios didn’t remove it for an industry screening of The Social Network in their flagship auditorium. But either way, what ends up happening is that they put he light-reducing 3D lens on, and then leave it on for 2D pictures! At the end of his article, he quotes Mike Humphries of Geek.com, who shares how you can tell if you’re getting screwed:

  • The title of the movie listed by the theater will have a “D” after it if it is being shown on a digital projector (Note: Fandango will write “digital projection” to make it clear.)
  • If you are in a D movie, look at the projector window when seated. If you see two stacked beams of light it is a Sony projector with the 3D lens still on.
  • A single beam of light means no 3D lens, or a different make of projector that doesn’t have the issue
  • If you see the two beams, then get up and go complain. You paid good money to see the movie, so make a fuss until they either give you back that money or remove the lens. Seeing as that’s an involved and time-consuming process, expect a refund.

I realize most won’t leave, but it’s good to know. I used to lean toward the showing with the digital projector, but now I’m going to think twice and try to find out which of my local theaters have the Sony’s and are too cheap to properly configure them between shows.

  1. As some commented there, you can have a single lens 3D system with a filter, but apparently it’s much easier to raise and lower that filter than it is to change the lens on a Sony. []

D&D Online Now Free

While I’m doing my best to avoid even casual video games, I recently discovered that the D&D MMORPG is now free. Apparently, they make money by selling optional equipment, characters, etc.. It sounds like they’re allowing you to pay cash for game gold, which of course you also earn in game. It’s 3.5 based, so all that knowledge (assuming you haven’t forgotten it all after moving to 4.0) won’t go to waste.

The best part is that by selling directly to gamers, it should cut down on Chinese prisoner gold miners. I know Blizzard is too greedy to cut off China, home to an estimated 80% of their gold farmers, but you’d think by now they’d set up servers for US only players, verified by credit card ZIP code and IP (with no proxies allowed). I hear it’s gotten so bad you need an addon to strip out the gold adverts in the chat stream…

Skipping Trailers and Warnings on Blu-ray Discs

There has been an increase in crimes against consumers. They are being held hostage. By what? Warnings and trailers on Blu-ray discs! I don’t steal movies off the internet, I rent them via Netflix, and rental discs1 are the biggest culprit.

Yes, you can fast forward, but on my PC’s BD player2 only goes so fast, so I’m still stuck for several minutes. Worse, I often need to stop the disc and get back to work, which means closing the player since it disables the Windows Aero interface and color scheme. When I start the player again, I’m back at square one! I’ve been looking for a player that allows me to skip anything, much like VLC Media Player and Media Player Classic (the open source version) allow me to do for DVDs. Unfortunately, I’ve seen no open source BD players and the commercial ones won’t dare allow you to perform a “user prohibited action” as defined by the disc makers. How they have the balls to charge $100 for that crap I’ll never know.

But we have a savior! It’s called AnyDVD HD. It sits between your BD ROM drive and your software player software and presents the disc as decrypted. It will also disable all your warnings and trailers.3. I just installed it and put in a disc and it immediately went to the main menu. It’s exactly what I was looking for and it’s currently going for about $75, with a 3 week trial so you can check it out first. Yes, a little pricey, but still cheaper than the other software players and I’ll make up for it in time saved. The bummer is that it only works on Windows, so when I have a home theater set up with my PS3, I’ll be back to slogging through trailers, or schlepping my laptop over to the coffee table.

  1. Denoted by plain grey discs featuring only the movie title. []
  2. HP MediaSmart DVD, which is just rebranded Cyberlink. []
  3. Of course, you can get to the trailers through the disc menu if you like. []

Best Money I Ever Spent

They say the best things in life are free. This may be true, but there are some pretty terrific things out there that do cost money. Some things are so good they are life changing. Here are the things that make me happy every time I use them or think about them.

Influence: The Psychology of Persuasion
$7.50
I could probably fill this article with fantastic books, but Influence stands head and shoulders above the rest. It’s the most powerful non-fiction book I’ve ever read. Not only does it explain how you can be influenced, but it uses social psychology to describe various phenomena like coups and revolutions. As Strongbad might say, it can be used for good or for awesome, so even though it’s on every list of the best marketing/business books, I hesitated to suggest it in public like this. Some of the techniques it describes are the closest thing we have to charm spells, so I didn’t want it falling into the wrong hands. But I’m sure I can trust the fine readers of this blog to only use it for good. Or at least not use it directly against me.

Lasko 5429 Oscillating Ceramic Heater
$30
I occasionally suffer from back strain, AKA a pulled muscle. Sometimes it’s just sore and inconvenient, other times I’m taking Advil and the day off from work. I noticed this occasionally happens when I’m drying off after a shower and decided to figure out why. Well, I learned that pulling/straining a muscle happens when you stretch it beyond the limit, and cold muscles get tight and are more susceptible to straining. I surmised that when you get out of a hot shower into a cold bathroom, your muscles can tighten up pretty quickly and get you in the danger zone. I remedied this by buying the Lasko heater to heat my bathroom up while I’m taking a shower. I don’t know conclusively whether this fixed the problem (I also dry off a little more carefully), but every time I step out of the shower into warm bathroom I think, “This is the best $30 I’ve ever spent.” Note that while it isn’t specifically rated for bathroom use, I’ve done so for 2 years without a problem. Just make sure you keep the bathroom fan off!

MovingHelp.com
$200 (but depends on size of move)
I remember from the movie Moving that moving is the third most stressful life event after death in the family and divorce. I used to compensate for this by getting friends and family to help me out, and reciprocate when it was asked of me. But I’m now getting old enough that when I hear someone is moving, I secretly think, “Please don’t ask me to help.” If they do ask I will help out, but I have to sheepishly explain how I’ve screwed up my knees and back in previous moves, so why don’t I just pick up the pizza and beverages?

Because of that, in my last move, I decided it wasn’t fair for me to ask anyone to help. I’d pack myself, but I was going to pay for real movers. That’s where Moving Help came in. It’s got a great rating/feedback system that makes it easy to find the best movers in your area. I hired a tall, wiry gentleman who brought 20 years of experience, 3 helpers, and all the extra crap U-Haul tries to sell (or rent) you: blankets, dollies, tie downs, etc. He even drove the truck! All said and done it cost me $200 and xcept for the packing, I barely lifted a finger. Note that if you’re extra lazy (and trusting) you can hire people to pack your stuff and clean your home as well.

Dell UltraSharp U2410
$500 (Black Friday deal)

When I traded my desktop for a laptop, I decided to upgrade my monitor as well. My previous monitor was a 21″ Hitachi CRT that I paid $1,100 for in 1997 and served me very well for over a decade. I was putting off going to LCD because of issues with color gamut and viewing angles, but the U2410 solves all of this. It features “PremierColor”, which has 110% color is gamut capable of producing over a billion colors (way beyond the traditional 16M colors of 24bit hardware). It is also factory calibrated and comes with a printout in the box that proves the color quality of that individual monitor. Right after connecting it, I was seeing detail in images that I never noticed before. I also love the matte finish, which is very forgiving of random light sources. It’s perfect for photography or graphic design.

There’s more. It has just about every connector you’d need: HDMI, DisplayPort, DVI, and VGA. It even routes audio from HDMI or DisplayPort to an 1/8″ mini-jack so I can use it to feed my computer speakers. Since this monitor does double duty as a TV, this works out perfectly. I’ve got an HDMI switch that handles both my laptop and my DVR, and changing the source automatically switches both video and sound. It also functions as a USB hub so I can connect the Tivo to it to download listings and software updates. It’s overkill as a television, of course, but I’m not complaining. Unless, of course, my eyes stray to my HP laptop display that I use as a red-headed step-monitor. Ugh, what a dog.

So, tell me, what’s the best money you’ve ever spent?