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Comment: Re:good principle! (Score 1) 62

by DarkOx (#49830179) Attached to: The Bizarre Process Used For Approving Exemptions To the DMCA

I think its an interesting idea but as you say congress would be almost entirely bogged down in re-upping existing /good/ laws. Even if a vote to 're-approve the federal statute against murder' takes only 60 seconds to execute you still won't get much done in a congressional session.

What I think might be more interesting is to require every legislative act to have preamble like the Constitution does. It should be required to be written in plain language at a 4th grade reading level, stating the acts broad objectives and intent. After say a period of 5 years anyone who is subject to the law should be permitted to challenge it in federal court for 'performance'. If the court finds the Act:

does not materially satisfy the objectives in its preamble
OR
has material unintended consequences (positive or negative the court should not be permitted to make a value judgement)
OR
has been materially used be the Executive for purposes not covered by the preamble

the law should be vacated.

Comment: space efficient (Score 1) 101

by DrYak (#49828917) Attached to: Mercedes-Benz Copies Tesla, Plans To Offer Home Energy Storage

In Japan and Hawaii power companies are installing grid scale batteries. {...} Ideal for smoothing renewable sources.

And I might add: easier for such (relatively) smaller islands like Hawaii which can't afford lots hydroelectric dam due to limited amount of mountains (compared to the Alps here around, or compared to Japan)

Comment: Re:The videos are bad (Score 1) 137

I think you may have misunderstood my bracketed remark.

What I was trying to say is that, since Windows 8 is universally despised, it can't be people defending Windows 8 who are thumbs-downing this video. There are too few to defend 8, and too many (who can't stand it) who would want to thumbs-up this video (if anything).

So, what is left is that people don't like the aspects of this presentation not related to a Microsoft operating system. This reflects badly on either the presenter (I've not watched the video), or the software/style of presentation, or both.

The net result is the same -- there is nothing here to recommend this style of presentation.

Comment: Answers. (Score 1) 588

by DrYak (#49827031) Attached to: How Tesla Batteries Will Force Home Wiring To Go Low Voltage

I do wish Slashdot would let you edit posts, then I wouldn't have to reply three times!

I'll group the answers.

Then why doesn't it happen more often?

Well, you need to stick needles into the body quite big and deep to have a good contact (the probes mentioned in this Darwin award). And apply a sufficient voltage to them, for a long enough time. That's quite a convoluted way that doesn't happen in every day life.
(I hardly see example how it could happen, except deliberately as in the example).

Actually a healthy heart will regain rhythm easily.

Generally speaking, yes, I agree. A healthy heart should restart.
That's in fact the principle which is used by defibrillators:
- a firbillation: is a big electrical mess where the cells a completely desynchronised and are firing mostly at random each triggered by the mostly random fires of their neighbours. Electrically, the heart gives a signal that looks like white noise. Mecanically, the heart isn't beating in a coordinated manner, but instead its surface is more or less kind of "vibrating" making tons of small uncoordinated local micro-contraction (that's what fibrillation means).
- fire a charge a the heart
- the charge cause all the muscle cells (and the specialized muscle cells that serve as the heart's equivalent of nerves) to contract at the same time and stay contracted for the short duration of the charge.
- after the shock, most of the cell are more or less at the same position in the cycle. (and thus none will start miss firing due to other nearby miss-fires). They are more or less in "waiting state".
- natural rhythm generator generates impulse as usual, and now all the cell should follow the same impulse travelling along the heart (and its nerve-like specialised fibers).
- heart should contract in a coordinated manner and beat as it should.

BUT....
In the Darwin awards example, the current is constant. Which doesn't cause a "resync" as the single pulse that a defibrillator's shock is. Also, given the low resistance of the salty water medium, the current is probably quite high which is dangerous. (I mean relatively speaking).
There's a much higher risk of the heart going into fibrillation in this case.

Of course adding some heart disease could increase the likely hood of dying.
But the absence of disease isn't a definite guarantee to die from such shocks.

I've had quite a few jolts from 240 volt mains from one hand to the other. Explain why I'm not dead.

Basically: you got lucky.

Probably the shocks where short. Or by luck the travel path of the current didn't happen to reach the heart (I've once had a thunder struck patient that survived exactly because of that: the heart wasn't touched).
The fact that you survived previous shock and the fact that you don't have a heart disease doesn't necessarily make you immortal and doesn't guarantee that you won't die next time.

Comment: Skin is the insulator (Score 1) 588

by DrYak (#49826647) Attached to: How Tesla Batteries Will Force Home Wiring To Go Low Voltage

That could very well happen.

The voltage and the current from a test meter are both insignificant.

The reason why low voltage isn't dangerous usually, is because the skin is a damn good insulator requiring voltage above 100v to break (one of the argument invoked by countries using 100volts, whereas the rest is 220v).

The Darwin Award example did stick needle-like pointy ends of the probe *through* the skin. The skin's high insulation/resistance wasn't there any more to shield against "insignificant voltage". The serum of the blood isn't distilled water but is filled with electrolyte. Quite conducting mix. It also runs through the hearth. The rest of the fuilds inside a body are all rich with electrolytes too. That means that the *inside* of a body can conduct electricity quite well, and the hearth can easily get in its path (specially if you put each electrode pole at opposite side).
(one of the reason why it's not a bright idea to swim during a storm. the inside of your body is a *better* conductor that the water around you in the swimming pool, the skin is the only thing in the way blocking the electricity).

The actual delta-V needed for a muscle cell or a nerve to react is quite low (a few dozens of mili-volts are needed to rise above the threshold and cause contraction or impulse propagation). So with the skin barrier removed, it's quite likely that the remaining salty fuilds (mostly blood, but also extra-cellular fluids) can carry enough to cause a jolt to the hearth, enough to disrupt the normal rhythm.

Comment: Chromium and Netflix (Score 1) 81

by DrYak (#49826253) Attached to: Emulator Now Runs x86 Apps On All Raspberry Pi Models

Only Chromium

You can google around and find several tutorial explaining how to compile chromium with support for Widevine turned on (That's the DRM module used by Google Chrome to play the HTML5 EME/VIDEO streams of netflix).

Now the question is:
- are there Widevine binaries available for ARM ? (Not sure. I might remember having read somewhere about such)
- or, alternatively, can similar JIT emulator as TFA's one run the x86 plugin at a sufficient speed, while leaving enough processing power to handle the remaining of the video playing ? (Luckily, there's some hardware acceleration on the Pi, so maybe it's possible to achieve).

You could do the same using a Firefox compile with support for CDM plugins, and using the Adobe CDM plugin for Firefox.
(With the same limitation, either wait until Adobe does an ARM version for all the various mobile incarnation of Firefox, or hope that the plugins can be emulated fast enough).

Comment: Energy storage (Score 2) 101

by DrYak (#49823639) Attached to: Mercedes-Benz Copies Tesla, Plans To Offer Home Energy Storage

wouldn't power companies be doing it?

Here around power companies DO INDEED do it.
And it's called a hydroelectric dam.

- You let it fill when unneeded (and thus store the energy as gravity potential energy). Or you can even actively pump water into it if you want to charge using electricity as an input.
- You start emptying it through the power station to supplement other energy sources when demand exceeds power capacity (as might happen with some forms of renewable energy).

On a really smaller scale, that has also been always the case with isolated usage of solar panels. When you're to remote to be connected to a power grid, instead of feeding the excess electricity into the grid and using the power grid later when needed, you store the excess electricity into batteries and retrieve it when needed.

(And in a way, if you think about it, lots of on-demand energy power-plants - e.g.: nuclear reactor - do in a way store the energy. Except that the form varies (e.g.: uranium/thorium don't store the energy as chemical states as lithium doesr) and usually can't be directly charged using electricity.)

So yes, power companies DO store energy. But due to the scale at which they work, they tend to chose denser (nuclear fuel) or bigger quantities (lakes at electric dam) than a a few kWh worth of lithium batteries.

Comment: Re:Cost effectiveness (Score 2) 101

by amorsen (#49823463) Attached to: Mercedes-Benz Copies Tesla, Plans To Offer Home Energy Storage

In many places electricity is taxed or high distribution tariffs apply. When you combine that with low feed-in tariffs, those with solar panels have a strong incentive to use their own power rather than export and import power.

Thus, it is cost effective to store energy for the consumer, not for the power companies -- and sometimes it is cost effective for the consumer to store energy expensive high-demand power from the middle of the day and use it during the night when power is otherwise cheap. Some power companies are investing in batteries to do the exact opposite, of course.

In the grand scheme of things there are larger fish to fry when it comes to tax and tariffs though, where the interests of society do not align with the incentives provided to individual people. E.g. it is rather stupid to tax labour, which is a clean and beneficial way to improve our society, instead of resource consumption which causes pollution and poverty.

Comment: Re:This makes me feel safe (Score 2) 327

The trouble if you are OBL type is that people are only so dumb. You can convience them to die for the cause but far fewer want to volunteer for a job that most like will result in their being captured not killed and living out there days being force fed at camp X-Ray.

IMHO the real vulnerability is the security line itself and the Boston bombing proves it. You can pack plenty of explosive to cause all kinds of carnage in bag that will plausibly be allowed as a carry on. Pick a busier airport, wait until you are in the middle of the security queue with people cordoned all around you in a big mass and BOOM! Most of these airports haven't got high ceilings and the screening area is in a corridor like space to prevent people from bypassing it. Look what the bomb in Boston did outdoors, think what harm it would do to people indoors!

Such an act would certainly have the effect of terrifying people, of going anywhere near an airport and probably anywhere else they might be forced to queue. Is it as spectacular as slamming a airliner into sky scraper, nope, but if executed well still stands to kill or maim 1000 people give or take. It will still make folks afraid to travel with all the associated knock-on economic impacts. The current system does nothing to defend against this type of thread in fact it makes it far more likely.

The whole cockpit door thing has more or less eliminated the reason a terrorist might have any interest of bringing weapons on a aircraft. If you can't control the plane anymore than all that is left to you is a Libyan style attack where you attempt to cause the plane to crash over a populated area. I suppose you might just want to transport weapons to an unrelated target as well but even the stupidest terrorists has to realize that there are ways to transport weapons with much lower detection risk than by airline. So I just don't see airliners being probably targets any more, when the airport offers a high probability of success, and will make a fine spectacle.

Comment: Re:No wonder it graphene sponge will move (Score 2) 256

by Jesrad (#49820465) Attached to: Fuel Free Spacecrafts Using Graphene

If I read this correctly, the decisive advantage this has over conventional solar sails, is that instead of turning a fraction of the (feeble) momentum of photons into useful movement (basically by bouncing photons around), this discovery turns (apparently, most of) the energy of those photons into a coherent emission of electrons, which give off orders of magnitude more useful momentum.

So, it's not quite a solar sail, but rather a very very very light and efficient solar-powered electron cannon.

Any sufficiently advanced technology is indistinguishable from a rigged demo. - Andy Finkel, computer guy

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