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Comment: Skin is the insulator (Score 1) 586

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 1) 73

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: PROTECTED speech (Score 1) 144

Fundamentally, not all communications are speech, because some communications have explicit direct non-speech results.

According to the Supreme Court, not all communications are PROTECTED speech. (They're still speech. They just don't enjoy the First Amendment protections because they're ALSO parts of crimes for which one can be punished - and in some cases (such as threats or criminal conspiracy) the speech is all it takes to commit or be a participant in the crime.)

Because speech is explicitly mentioned as protected in the First Amendment (and anti-government speech is also specifically a necessary part of another protected right - petitioning the government for redress of grievances), the court sets a very high standard for laws making some kind of speech a crime: Such laws may be overturned just because they have "a chilling effect" on protected speech, by making people avoid such protected speech out of concern that it might be prosecuted.

Regardless, Congress doesn't get to pass laws that preemptively muzzle people or block publication. They just get to pass laws to punish them AFTER they speak (or print, ...) some explicitly illegal content.

Yelling "fire" in a crowded theater isn't speech.

Funny you should mention that. The phrase "FALSELY shouting fire in a crowded theatre" originated in a WWI Supreme Court decision declaring that distributing anti-draft leaflets to people of draft age was not protected speech.

My favorite approach to "Fire in a Crowded Theatre" was Abbie Hoffman's (when being interviewed in a crowded theatre):
    Interviewer: "But surely you don't advocate shouting fire in a crowded theatre?"
    Abbie: "FIRE!"

Comment: Not remarkable at all. (Score 1) 81

Anti-malware companies try to appear as experts.

Malware authors try to be anonymous, leaving minimal personal signature in the malware. Malware authors also share code and reverse-engineer each other's code and use the result, so even style may be misleading. So even experts would have difficulty attributing it to any particular person,

That means any attempt to identify the author - as a real person, an alias, or a label under which to group multiple products of the same author, will be very error prone. With law-enforcement and other security types attempting to defend against and/or apprehend the authors, and the authors trying to hamper the anti-malware people and companies some of these errors would come to light. This would reduce the reputation of the anti-malware workers and companies, without regard to their success at malware defence.

So it is no surprise to me that andi-malware people and companies don't publish the results of any attempts they may make to identify the authors in the course of their work. Why should they take a risk like that for no perceivable gain? The risk/benefit ratio says don't even speculate.

If it wasn't for Newton, we wouldn't have to eat bruised apples.

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