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Comment Re:Better be careful, people (Score 4, Informative) 325

A few small air bubbles, while not ideal, are not as bad as you might think. An important reason that you use the Hollywood-style flick-flick-flick to get air bubbles to the top of a syringe and then press them out is to make sure that you've filled the syringe with the appropriate amount of drug. Whereas 0.2 cc of air probably won't do much to you if injected (and that's a pretty big bubble in a syringe), if you're injecting 1 cc of drug, that 20% difference with versus without bubble can make a big difference in the mount of drug that actually gets delivered.

Comment Re:HP Printer Issues (Score 1) 386

We are beginning to think HP is having some major issues with their company.

I believe the issues you are finding would stem from Carly Fiorina. She did a world of bad for HP, a once great company. I used HP equipment starting many decades ago. It used to be that when you bought an HP instrument, it was indestructible. I quipped to a fellow student of mine when in graduate school that if the high-powered HP power supply we had just bought on the used market worked, it would work for ever. And, I was right.

For equipment from a specific era, it's hard to beat HP.

But, regrettably, that era has passed, and Carly Fiorina put the last dozen nails in the coffin.

Comment Re:Cause (Score 4, Interesting) 266

If you look at the published video on YouTube of the explosion and go frame by frame, there are two events. The first is a bright flash that lasts a few frames and appears much larger than it actually is because it is both saturating the camera and illuminating the condensation clouds. You can see the illumination effect clearly in the first frame the flash appears as there are distinct shadows in the clouds. It's unclear to me whether this triggering event is electrical or chemical in nature, but I'm not an expert. Three observations can be made, however: (1) it is bright enough to cause lens flare in the camera which allows pinpointing its source despite the saturation (look for the X, carefully find its center -- you can do that very accurately -- and then back up a handful of frames; see that triangle thingy with a thin tail? That's what failed.) Then, (2) the initial flash is small and is followed almost immediately by a medium sized flash, and in turn that releases the fireball. Then, (3) the condensation clouds aren't moved by the explosion for about 12 frames until the fireball really starts to form, suggesting that the earlier flashes marked the release of lots of energy that may have been primarily radiation (light) rather than heat because they didn't expand the air enough for me to think of them as explosions. The video is 60 FPS, and the initial flash forms within one frame, so that's only 17 ms. The consdensation clouds don't start moving for 200 ms from the main explosion.

So we have one event that's exceedingly hot that triggers a second that's also exceedingly hot, that releases enough LOX to start the fireball. I'm thinking static discharge from the LOX filling.

One thing I don't understand, though, is that if you watch the fireball in slow motion, as the lower front heads toward the ground, there are seemingly waves passing through it. What are those? Additional shock fronts from tertiary explosions?

Comment Re:TVS Diode. (Score 1) 308

Except that a rock would be a lot more obvious, and if you wanted to socially engineer a company into self-destruction of property, just leave one of these USB-killer things disguised as a normal flash drive in the parking lot.

Now why you would want to destroy the USB port and possibly the computer it is part of rather than deliver malware if you have nefarious intent, well, that beats me. Destroying the computer causes limited damage. Malware, in contrast, can propagate.

Nevertheless, if vandalism is the goal, rocks will do, but gum, half-chewed soft candy, or a squirt of glue will still disable the port and require a visit from a field tech. One might imagine that gum is a far more pervasive nuisance to public-facing USB ports than rocks.

Comment EM sensitivity explained? (Score 1) 93

Any chance that EM sensitivity is really caused by magnetic particles in the sufferer's brain?

One pre-mortem way to look for evidence is to see if there's a correlation between length of time spent in zones of high air pollution and complaint severity. Heck, if magnetite is found in the brain, then it must be in the blood stream, too, and other tissues as well. There's potentially some serious science to be done here.

Comment box, maybe? (Score 3, Interesting) 299

"He actually found a USB that was in this jar that was closed, and the jar was in a box, and the box had stuff in it. The jar itself had stuff in it."

Maybe, just maybe, he didn't smell the USB flash drive that was in a closed jar inside a box. Maybe, just maybe, he smelled the residue that the owner had left on the outside of the box when putting the flash drive away.

It's very, very challenging to completely isolate something from ordor-based detection. You need to work with clean instruments and put the item in a clean container, operating ideally in a clean environment. Then, because you probably slightly contaminated the outside of the bag, you need to do it again, with a completely new set of clean instruments, in a new, clean environment. And then you probably need to do it again. And probably again.

Otherwise, the owner might as well have just rubbed the flash drive on the outside of the box.

Comment Re:Here's an idea... (Score 3, Insightful) 260

And yet, no terrorists. No bridges or malls or trains or buses blowing up, no water being poisoned, etc.

Perhaps not in the US, but in Nice, France, there was recently that Tunisian fellow who drove a large truck through a crowd (on the sidewalk) for two kilometers, killing nearly 100 people, and injuring slightly over 200. Pretty good soft target: a diffuse crowd gathered for Bastille Day celebrations. Quite effective terrorism.

Then in the US, there was that couple in San Bernardino who shot up a Christmas party in 2015. Another effective act of terrorism on a soft target.

And the recent shooting in the night club in Florida.

And the Boston Marathon bombing.

Oh, and the ricin mailed to a senator and the US president.

(and there are more)

So what were you saying again?

Comment Re:So... (Score 1) 252

And when the POAM is being tracked, and things aren't getting fixed .... oh, wait, *I* know, we'll put together a Selected Hurdles Integration and Testing Facility Engineering System Template to make sure the problems get resolved.

The deal is that once you've spent big money, you just can't back out and save face. They need a new leader, brought in from the outside, to shred the contract and tell HPE to go away.

Comment Re:I don't get it (Score 1) 130

I think you've hit the nail on the head. Nevertheless, I do want to point out that there is a simple case where a pressurized tank will hold just fine, but will leak like a sieve if the pressure is lowered: an internal flap that is being held in place against a hole by the high pressure, that is no longer being held sufficiently tightly when the pressure is lowered. The flap, in this case, might well be unintentional, like from an overlapped seam of two panels. It turns out that the flapper valve in most toilets works just in that way: it depends on the weight of the water to ensure a good seal, leaking terribly during the initial filling of the tank. The toilet valve is designed to do that, but after shaking the begeezus out of a lift stage that has been designed neither for low-pressure use nor for long-term durability, there might well be such flaps unintentionally present.

But the primary point is that we agree -- the basic idea is worth pursuing. Given the vast cost of lifting the shell to orbit, it would seem to be a resource that could be utilized, somehow, and that bears investigation.

Comment Re:I don't get it (Score 3, Insightful) 130

It is pressure tested at many times the 0.5-1.0 atm pressure differential needed to sustain human life in space.

It is pressure tested on earth before being subjected to the intense rigors of launch. All bets are off as to whether it retains long-term integrity, as it has not been designed to do that. It's easy to find situations where a vessel will will not leak at high pressure differentials, but will leak at low pressure differentials. That we don't know the answer as to what will happen to the current designs is a good reason to test, but it should not be put forth as incontrovertible evidence of future success.

Comment waste of money (Score 1) 226

1. No, simply no. It makes my eyes go funny.

2. No. Cute ways to make graphics spell out a company's name is a first-year student's approach. You can do better. It looks like a QR code FFS.

3. Interesting. But what does it have to do with browsers? Is Mozilla now making robots? Or a chat app?

4. Cute. Will not be cute in about 18 months.

5. No, and see point 2 as to why. It also does not render well at 32x32.

6. Makes my eyes bleed almost as much as #1. Also will not render well at low resolutions. FFS, why do I want to recall those horrid Apple drawing programs from the pre-iMac days?

7. What? Which part of that is the logo? Is Mozilla an origami company now? It's supposed to read Mozilla? See objection to #2.

The only one that has any relevant design sensibility (note the important "relevant" part ... the open elevator door logo is sheer idiocy, unless Mozilla has bought Otis Elevator and no-one's noticed) is the fourth Moz://a, but it will get tired quickly. Cute does not last.

Now, can anyone tell me what the Mozilla logo currently is? Not the Firefox logo. Not the Thunderbird logo, but the Mozilla Foundation's logo. Anyone? Anyone? So the logo does not matter one whit. (The logo, having looked at the web site appears to be a lower-case "mozilla" in an attractive sans-serif font; not a bad logo, kind of bland, but lacks the iconic symbology that is regrettably so popular right now.)

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