[CentOS] Power-outage

[Robert Heller]

At Sun, 3 Jul 2011 00:34:18 +0100 CentOS mailing list <centos at centos.org> wrote:

> 
> On Saturday 02 July 2011 21:13:59 Robert Heller wrote:
> > > I'm using an UPS for my desktop system, but I don't need it for the
> > > laptop. If the AC power drops, even for a moment, the laptop battery
> > > will kick in and sustain the machine. I just think that the same thing
> > > can be implemented for the desktop too. If I understood the OP
> > > correctly... ;-)
> > 
> > A laptop effectively contains its own UPS in the form of a power brick,
> > battery and power supply on its motherboard.
> > 
> > Yes, one *could* build a desktop or server that way, but why bother,
> > since AC wall outlets are everywhere one might want to use a desktop or
> > server?
> 
> Well, one reason I can think of is that one cannot always trust the AC wall 
> outlet to provide uninterrupted power? By that I don't mean AC power going 
> down for an hour, but for a fraction of a second.
> 
> I happen to live near an industrial zone, and every morning between 10 and 11h 
> someone turns on something in the nearby factory, which makes my light-bulbs 
> blink twice. Of course, that's enough to reboot my desktop machine no problem. 
> I had to buy an UPS system just because of that. Granted, an UPS turned out to 
> be a good investment, but still I wonder why there are no offers on the market 
> with a "boosted" PSU units that can sustain DC power for a couple of seconds 
> during the AC "blinks". They don't even need to use a battery, maybe a set of 
> condensers could sustain power for a short period (although I might be wrong, 
> never did the numbers on that).
> 
> A friend of mine lives near the Technical Sciences university (in the middle 
> of the city, they don't have a campus), where they have a medium-sized wind 
> tunnel for the aero-engineering courses. Every time they turn the thing on, 
> the whole city block loses power for cca 5 seconds. Sure, it's bad AC grid 
> design, but bad designs are usually a fact of life. :-)
> 
> I'm speculating here about an improved PSU device which would be more 
> expensive than the ordinary one, but less expensive than a typical UPS system. 
> Given that I believe there certainly is a market for such a PSU, I'm just 
> surprised nobody is selling it yet. You cannot assume that the AC wall outlet 
> will always provide perfect power... ;-)
> 
> > There is (in the SciFi world) the idea that someday
> > 'desktops' in the current / conventional sense may completely vanish
> > from the universe, taken over progressably by laptops, tablets, smart
> > phones, wearable computers (motherboard == shirt, monitor == shades,
> > power supply == hat with embedded solar cells, virtual mouse/keyboard
> > via motion sensors in your shirt sleves/gloves, etc.),
> 
> I could in principle imagine all that coming in the future, but the
> "monitor == shades" thing is just only Fi with no Sci in it. A human eye 
> cannot focus properly on any object which is closer to the eye than 10-15 cm 
> (depending on the eye quality), so there is absolutely no way one can use 
> shades or contact lenses or something similar as a monitor, regardless of 
> technological levels of any human or alien races (James Bond notwithstanding). 
> Unless of course one surgically adapts the eye lense itself, in which case the 
> person would not be able to see anything else... ;-)

Hmmm... There were a CS prof. and some students at UMass when I was
working there playing with a computer in a backpack with a 1" monitor
suspended from a head mount in front of one eye.  Not anything like
10-15 cm.  If 10-15 cm is the minimum distance, what about telescope
eyepieces, camera viewfinders (including the little video ones on
camcorders), or binoculars? *I* know I can see images in the video
viewfinder of my Sony Hi8 camcorder just fine, with my right up close
(the old camcorder I have does NOT have a 3" swing out monitor). It is
all about the optics.


> 
> > or even
> > implanted computers (eg as a thin circuit board between your skull and
> > scalp, and 'wired' directly into your brain).
> 
> I would never wire a brain to a machine. Brains make errors, are susceptible 
> to emotions, hormons, vanity, etc., and just introduce a large point of 
> failure for the otherwise-correct machines. ;-)
> 
> > This seems to already be
> > happening to some extent, in that laptops are becoming the computer of
> > choise and desktops are becomming an 'old school' sort of thing.
> 
> Yeah, the laptops are becoming cheap enough, so that once your computing needs 
> grow out of your current laptop, you don't even think of "upgrading" it, but 
> rather just buy a new model. Desktops will be in use only for custom things 
> (professionals who need, say, five audio cards in one machine) and small 
> servers. But we're getting sort-of OT here... ;-)
> 
> Best, :-)
> Marko
> 
> 
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>             

-- 
Robert Heller             -- 978-544-6933 / heller at deepsoft.com
Deepwoods Software        -- http://www.deepsoft.com/
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