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Comment Re:satellites (Score 1) 403 403

Most of the US Navy's nuclear ships are setup to be refueled at least once in the expected lifetime...but that's not the main thing here. The steam plants on these ships leak (clean, not radioactive) water/steam when they operate. So much so that they have built-in make-up systems to replace the lost water. Eventually the tanks that store the make-up water will run dry, and new tanks must be placed in service. Doing this is a manual operation - sailors turning valves.

I don't know how often this must be accomplished, but there's no way it's more than a week before it must be done. If it is not done, I'm pretty confident you have less than a day before some alarm/safety system detects low water levels and stops feeding the boilers. After that happens it won't be long (minutes?) before a different safety system shuts down the reactor.

Comment Re: I dunno about LEDs, but CFLs don't last (Score 1) 602 602

A regular cause of early incandescent bulb death is vibration. I wonder if there is a way that opening/shutting your door or walking on your porch vibrates the light socket? I had the same kind of issue in my basement, walking in the kitchen would vibrate the basement ceiling, and if the lights were on in the basement one might burn out.

I replaced them with CFLs and everything has been good. I put the same kind of CFLs in my garage. The starters all died on them after about 6 months, presumably from either humidity (I live in the US midwest) or maybe it was the cold? Dunno.

Point of the post is that lifetime numbers given by the manufacturer are probably for the "best case" condition for the bulb to live in. I imagine in FL where they get far more lightning than in the US that LED bulbs might have a shorter life.

Comment Re: Read Slashdot (Score 4, Informative) 479 479

I've worked with PhDs in a hands-on environment as well (apps/drivers and low-level embedded stuff). Several of them were great, and at least one sucked enough to be let go. One of them (Physics PhD, not Comp Sci) was one of the most talented low-level embedded SW Eng's I've worked with. Sweeping generalizations...

Comment Re:Maybe it would be good if the Ayatollah wins? (Score 1) 542 542

You've got a point there. The summary article on Wikipedia has 21 nations listed as having some kind of Arab spring activity, but only 3 with good-ish outcomes.

Next way-out-there question: The US is pretty tired of middle east involvements right now...but if there was a significant revolt in Iran, would the US jump in? Fund rebels? Deliver arms?

Comment Maybe it would be good if the Ayatollah wins? (Score 5, Interesting) 542 542

Imagine if 3G (and "4G") was found to somehow be illegal in the US - I think there'd be a revolt. A good enough chunk of the nation expects to get FB updates and cat vids on demand anywhere they go. Maybe Iran is the same? It seems backwards, but I think this is the kind of thing that gets the average person to actually care about something. No cat vids = Arab spring in Iran? Maybe?

Comment Re: Don't imagine it stops there. (Score 2) 348 348

Given that the aircraft contains hundreds of thousands of parts, I'd be willing to bet more than just a few "China" parts have slipped in. It's one thing if it's some $10,000 part...but for a handful of $2 magnets (which if we did go to war with China could be found in stockrooms all across the US) who cares. Don't get me wrong - this should be avoided. It happened as an oversight and a waiver was granted. Thats the kind of thing waivers are for. We don't need Uncle Sam spending $100K to replace $2 magnets.

Comment Re:Really? (Score 1) 580 580

I think we need to read between the lines. I bet Tyson realizes Musk is the kind of guy who can't lose a bet and is daring him. Obviously this is speculation and I could be wrong, but I think Tyson is playing chicken with Musk - except Tyson wants to lose. Tyson is a brilliant guy. He's also all about getting people interested in the cosmos, and getting funding for the required research etc. Musk is also a brilliant guy, and we all know he's a daredevil. Look at his businesses (which are quite successful), high performance electric cars and rocketry. He was also a founder of Paypal back when doing that kind of thing wasn't a "sure bet". Musk is also all about the technology, and he's an innovator.

Comment This is going to be a mess... (Score 1) 297 297

So is this tax a federal sales tax, or is it going to allow the states to collect sales tax? From the article (which was vague) it makes it sound like it's going to allow states to collect and is to benefit states / local economies. That sounds great (not really), but...

...how long until I'm paying taxes to two (or more!) states for a purchase online? (Tax to my state and tax to the state where the merchant is)

I can't find the bills online (spent 5 minutes on senate.gov), so I can't see if the bill provides some direction on which state gets to collect the tax. If someone finds the bills it would be great to provide a link.

Comment Re:Math? (Score 2) 589 589

The AEGIS interceptors are not as sophisticated as you'd think. All of the directing comes from the ship's powerful radar. The ship tracks the inbound missile, and when the timing is right launches an interceptor (the Navy calls them "Standard Missiles" or SMs). The missile has no idea where it's going or what it's supposed to hit, in fact it doesn't even know where IT is. It's only real link to the world is it's ability to listen to the ship's powerful radar. The same radar that detected the threat can also see the SM. It basically hits the SM with radar in a special way that tells the SM "go up", "go down", "turn this much" etc. and guides it into the target. At the very end of the flight there is a terminal phase that is a bit different, but it's still the radar doing the heavy lifting, not the missile. Most of this is called out in more detail in the wikipedia page for Aegis Combat System.

Comment Re:We've become too comfortable. (Score 1) 518 518

I could possibly understand poorly written firmware (or some other "embedded software") damaging the hardware. If something at the driver level is capable of damaging the hardware, you need to fire your EE (and all reviewers and quality folks that signed off on the design). I don't remember any OS install updating device firmware.

Which leaves me thinking - is the HW in modern PCs that haphazard or is newegg (and others) trying to conserve a profit margin? I hope it's the latter.

IBM Advanced Systems Group -- a bunch of mindless jerks, who'll be first against the wall when the revolution comes... -- with regrets to D. Adams

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