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Comment Re:Calibration (Score 2) 194

Ablation can in theory remove single atomic layers with thermal damage only a few atoms deep to the underlying surface.

So the damage to the surface is only a few times larger than what was removed?

The damage is only a few atomic layers deep, more or less independent of how much material is removed.
A large limitation to how much you can remove is that you build this huge largely opaque cloud of debris blasting off the surface of the material so you can't get new photons into the surface anymore, but you can peel stuff off a few atoms in a burst or a few dozens of micrometers in a burst, with the same very thin heat affected zone at the surface. (Another is that all the stuff you just blasted off immediately sticks to the front of your objective lens, but they don't last long anyway when you have this many photons going through them: objective mirrors last longer but still get covered in junk. Some interesting stuff being done using liquid waveguides through which the laser moves and which wash off the debris, but then you have to not vaporize/ablate your liquid waveguide. And at least with the UV stuff we were doing, even the atmosphere absorbed giant amounts of the energy, so we had to do it in a vacuum and that made the crap-sticking-to-the-lens problem even worse.) My recollection is that people were trying to use laser ablation to do extremely thin heat-treatment, like surfacing treatment, but couldn't actually get it thick enough to make a measurable difference in wear characteristics, but A: I may misremember and B: people may be better at this now, so that bit could be complete hooey. I got out of high-energy lasers like fifteen years ago, when I realized that fully half my coworkers had pie blindness: they'd managed to damage some part of their eyes so they were missing some of their visual area, and stuff may have progressed a lot since then.

Comment Re:Calibration (Score 5, Informative) 194

Sorry to reply to myself but since Wikipedia doesn't actually bother to talk about mechanisms, I will. You can remove a surface with a laser through heating, which applies enough photons to the surface atoms that they vibrate loose, which is a slow process that transmits piles of heat downwards. Or you can use a laser whose wavelength is shorter than the strength of the sigma electron bonds in the material, in which case the electrons absorb the photons, get popped into a higher orbital, and the bond that held the two atoms together simply isn't there anymore and the now free atoms can just drift away. There is in theory no heat generated at all. In practice there are so many photons coming in all at once that there's a metric buttload of photons being absorbed by everything, so what actually happens is the wavefront hits and turns the first couple of atomic layers into a plasma, that erupts away from the surface and leaves the underlying surface close to untouched. So that's the mechanistic difference between burning and ablation: photon flux and wavelength.

Comment Re:Calibration (Score 1) 194

Seems like it would take some careful calibration to make a laser that would burn off wet leaves plastered to the rail and yet not soften the hardened steel of the rail that's going to have a multi-ton train passing over it in seconds.

If I were doing this -- and I'm not claiming it's feasible, but let's call this a gedankenexperiment -- I'd use a system set up to ablate the material, which Wikipedia says so I don't have to: "Very short laser pulses remove material so quickly that the surrounding material absorbs very little heat, so laser drilling can be done on delicate or heat-sensitive materials," and " laser energy can be selectively absorbed by coatings, particularly on metal, so CO2 or Nd:YAG pulsed lasers can be used to clean surfaces, remove paint or coating, or prepare surfaces for painting without damaging the underlying surface. High power lasers clean a large spot with a single pulse."
When I was working with deep UV lasers (and got to learn what fluorine gas smells like -- elmer's glue, in case you were wondering, at least when it's dilute -- we were able to strip physical vapor deposition copper and nickel off polyimide film without damaging the polyimide. (We needed geometries too fine for chemical etching.) Removing organic material off steel should be much easier. Ablation can in theory remove single atomic layers with thermal damage only a few atoms deep to the underlying surface.

Comment Re:Too lazy to protect themselves (Score 1) 528

I mean even shutting down the gym (who knows why, terminals?

My company, which isn't quite as bit as Sony, but close, has badge access to every door in the building besides personal offices, with badge access control handled by servers located at corporate HQ. If you don't keep up with your ESD training, you're automatically barred from the labs, for instance. If Sony has something similar and they start taking stuff offline to stop leaks, there will be lot of side-effects.

Comment Re:Sounds good to me (Score 1) 238

You should get a cert warning if they are using any kind of SSL decryption. Also, *most* companies that I know use such things specifically exclude banking and medical sites from decryption for legal reasons.

Cool, thanks. I trust my corporate overlords and potential rogue elements within IT about as far as I can throw them, so I try hard to restrict what I do online to let them see as little as possible.
Well, except for this, which is going through the internet in plaintext. Yay.

Comment Re:Sounds good to me (Score 1) 238

Mod parent up. I was going to post the same thing. There are numerous appliances and software solutions used by enterprises to do this, but to do it seamlessly you have to install a new certificate on the client machine.

Maybe you'd be the correct person to ask. I'm worried about exactly this, so as I have enough admin rights on my company computer to install software, I installed virtualbox and am running a linux system within that. My understanding is that since I performed the linux install, when I fire up a browser within the linux install and use https, I should not be susceptible to router-in-the-middle https proxy attacks -- or, at least, I should get a warning the first time I try to go to a site with https, letting me know about a certificate mismatch. Is that correct? or am I still open to the possibility of giving every IT person in my company access to my bank account if I were to do online banking from work? (I don't, but I do use gmail, which is https.)

Comment A what? (Score 4, Insightful) 139

>your dreams of tech as a clique-free meritocracy

How is a meritocracy not just another type of clique?
How is hiring people for their excellent social skills not a meritocracy?
There are so many implicit values embedded in the statement that it becomes a declaration of an extremely specific type of workplace the submitter (or editor) wants and thinks everyone else should want as well. It's the equivalent of the guy without a knife asserting that the guy with the knife should drop it and fight like a man.

Comment Re:Slashdot, once again... (Score 1) 289

Believe me, Americans are baffled by the religious extreme in our country too. I dont think i will ever go to Utah, for any reason because of extreme theocratic control. Sure its still America, but your neighbors will be pricks if you arent one of them (mormon)

I hate to defend institutions I don't like, but.. give Utah a chance. It's really beautiful, like, some of the most beautiful geology in the whole country. I spent last weekend there, as I have many previous weekends. Mormons are individually pretty nice people, despite the history of the church and many of its current political activities, and if you don't live there you don't get the shunned and isolated feeling that non-mormon residents get. Even rural towns now have coffee shops and places that serve beer.
For hostility and small-town religious closemindedness, northern Wyoming, northern Idaho, and North Dakota all feel far worse than Utah, to me.

Comment Re:Slaves are always cheaper than the free (Score 3, Interesting) 454

When will we finally get to a ruling class no longer pining for the pre-civil war days?

A friend who teaches economics was posting about this the other day. Her contention is that for all of history until the 1800's, it was fairly easy to just leave and go find some subsistence environment, so if you wanted workers you had to enslave them and force them to work for you. Now that it's not generally possible for most people to find environments for subsistence lifestyles, there's no longer any need to enslave people. They have to find jobs to survive. At that crossover, work stopped being something the lowest class of society did under force, and became something that was considered a privilege.

Comment How much of the work do you want to do? (Score 1) 195

As others have said, Subarus and Hondas are fairly easy to hack if you want to change existing ECU's.
But if you want a car the way you want it, and are going to do more work, look for older cars.
I have a 1975 Triumph Spitfire. I added electronic ignition, replaced the mechanical speedometer and tachometer with electronic ones, and am working on a custom fuel injection setup. If I want to put seat heaters in the car, removal of the seat pan doesn't take any bolts at all. It takes four screws to pull the door apart.
The problem, of course, is that I have to do ALL the work myself. There isn't anyone else doing stuff like this, so every project is brand new.
But there are precisely zero software or firmware barriers to doing anything I want, and the only hardware barriers are my skill limitations.
It's an easy way to sink 3000 hours into a car only worth $2000USD, though, and at the end you still have an old car with very dubious reliability.

Comment Re:absurd generalizations (Score 1) 71

You probably already know all this, but for what it's worth, Gary Klein's realization that you can build a stiff frame out of anything if you just increase the diameter enough is completely apropos for wooden bike frame design. The problem, as the Renovo guys have found, is that you need like 5" diameter tubes to get even acceptable stiffness, since stiffness rises as the third power of diameter for tubes. But at those diameters, for a competitive weight, the walls have to be like sub-millimeter in thickness, making for an incredibly delicate bike. (Even old top-end aluminum Cannondales were notorious for having holes punched right through the downtube when the bike merely fell over in a garage and landed on some heavy steel thing.) So Renovo's going down the route of making egg-crate-like tubing with huge amounts of milling to form internal honeycomb structures. Most everyone else in the wood/bamboo bike frame world has shrugged and accepted a more flexible frame as the cost of aesthetics, but in some cases like triathlon bikes it's okay to have a flexible frame as long as it's aerodynamic.
Of course, making a wood frame and then wrapping it with a layer of something with a really high young's modulus gets you a great frame... but then it's really a composite frame that uses wood rather than foam as its form, so that hardly counts.

Comment A long and current history of wooden bikes (Score 4, Informative) 71

There has never been a time when wooden bikes weren't being made. As late as the 1930's, people were making bikes with wooden compression-type spokes, rather than steel tension-type spokes, and currently there are piles of amazing wooden bikes being made.
This Owen was used as a triathalon bike, with some very respectable finishes (race finishes, not varnish finishes): https://www.flickr.com/photos/...
Satoshi Sano has been building spectacular bikes using traditional Japanese boatbuilding techniques: https://www.flickr.com/photos/...
and
http://sanomagic.world.coocan....
Note internal cabling in steam-bent frame elements, and a wooden seat on a steam-bent seatpost.
And since bamboo is wood, there are at least a dozen companies using bamboo as the primary frame material.
Calfee started it, as far as I can tell:
https://www.flickr.com/photos/...

But there are many others, like Panda and Boo.
Bamboosera makes a great Cannondale-shock mountain bike:
https://www.flickr.com/photos/...
and Hero Bikes make work and utility bikes:
https://www.flickr.com/photos/...

Hero (and at least two other companies) go so far as to offer classes, where over a weekend you start out by harvesting bamboo, and end up making a complete ready-to-build-up frameset.
http://www.herobike.org/collec...

Comment Re:reflexes? (Score 1) 114

My mother likely has a damaged visual cortex. She was born with double vision and had surgery to correct this. Unfortunately, even though the surgery successfully fixed her eyes, she still sees double. She'll see one image up and slightly to the side of the other - all blended together. Don't ask me how she drives, reads, or even maneuvers around. I wouldn't know which objects (seeing two of everything) to avoid but she has adapted and is used to it. She has said that, to her, it seems natural to see 2 of everything since you have two eyes and seeing one just sounds foreign. (3D movies don't work for her, thanks to this though.)

I don't know if she's already looked (so to speak) into this but she sounds like a possible candidate for vision therapy. They're pretty good at dealing with exactly this sort of problem without surgery, and through use of cleverly designed exercises, training eye muscles to consistently maintain image fusion. It certainly has limitations: they can't fix problems because of nerve palsies or damage that leads to muscles that simply don't work. But if the muscles work at all, they can often do some pretty amazing things.
It's expensive and most insurance plans don't cover it. But what price would you put on having good depth perception?

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