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Larry Rosen: A Case Study In Understanding (and Enforcing) the GPL

queazocotal The viral argument is misleading. (191 comments)

You distribute compiled code with GPL integrated, without complying with the GPL.

If this is discovered, then your customer has no right at all under the GPL to your whole code, and the GPL can never give them any rights.

The only way you can come into compliance with the GPL is to distribute sources for the whole blob - but in practice what has to happen to compel you to do this is for you to either decide that it is easier doing this than going to court - or for an author of the GPL code (or for the FSF where authorship has been assigned) to take court action for violating the licence - and then for the court to as the penalty require the release of source code.
The court is much more likely to go for financial damages - as that's what they know.

about two weeks ago
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Why the "NASA Tested Space Drive" Is Bad Science

queazocotal Re:A little behind the times (315 comments)

"* they did pretty much all of the things you would like to see (such as reversing the direction and making sure the thrust reverses).

* they seem to have done a thoughtful and careful job, including testing in vacuum."

Read the article carefully.

They did not actually test in vaccum. They tested at atmospheric pressure, because they did not have suitable vacuum rated amplifiers.
Spending half a page explaining how the vacuum system worked, only to have a throwaway line later in the paper (search on electrolytic) that they diddn't
actually use it is at best shoddy writing.

To quote from an earlier post I made on this.
The net torque is zero - yes.
The problem is that because the 'vacuum' chamber wasn't part of the measured system, you can exert torques against it without issue. Convection can do this and distort the measurement.

A major reason why this can't be true - or if it is it's bigger than any Nobel Prize-winners discovery in history, and maybe all of them:
The reported thrust in the NASA paper is 0.4N/kW.
Power = force * velocity.
If you put this on a railway car going at 10m/s, then you get 0.4W*10m/s = 4W out for 1000W in.
If the car is going at 100m/s, it's 40W.
At 3000m/s, 1200W.
You take 1000W of this to run the engine, and you now have 200W of free energy.
This can be arbitrarily scaled up.

If it works, it is not only a space drive, it's a perpetual motion machine that needs no fuel and emits energy.

about two weeks ago
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Rosetta Achieves Orbit Around Comet

queazocotal Sloppy reporting. (54 comments)

It is not yet in orbit. (or rather - at the moment, propulsive manouvers are dominant - you can technically say you're in orbit if you jump off the ground, and not be wrong)
Protip - orbits aren't triangular.
https://www.youtube.com/watch?... - is a two minute animation from ESA explaining the manoevers.

10th sep - it begins its first orbit at 30km - and about 14 day period. After about half an orbit, on the 17th of Sep or so it is tilted 80 degrees and still remains in a 30km orbit.
After a complete orbit, it then moves into 20km orbit, and around Oct 10, 10km.

about two weeks ago
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NASA Tests Microwave Space Drive

queazocotal Re:Ugh (201 comments)

Doh - in addition - the full article is available - http://www.libertariannews.org...

The reason given for not testing under vacuum is the unavailability of vacuum qualified amplifiers.
This is a very poor excuse - literally an hour is enough to make a vacuum sealed can into which you can put an amplifier.
You add a water-bottle and a fan, and you're good for some time.
Flushing the chamber with helium would have been a good and very fast step.
Turning the vacuum pump on, to pump out 1/3 of the air similarly.

about three weeks ago
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NASA Tests Microwave Space Drive

queazocotal Re:Ugh (201 comments)

The net torque is zero - yes.
The problem is that because the 'vacuum' chamber wasn't part of the measured system, you can exert torques against it without issue. Convection can do this and distort the measurement.

A major reason why this can't be true - or if it is it's bigger than any Nobel Prize-winners discovery in history, and maybe all of them:
The reported thrust in the NASA paper is 0.4N/kW.
Power = force * velocity.
If you put this on a railway car going at 10m/s, then you get 0.4W*10m/s = 4W out for 1000W in.
If the car is going at 100m/s, it's 40W.
At 3000m/s, 1200W.
You take 1000W of this to run the engine, and you now have 200W of free energy.
This can be arbitrarily scaled up.

Is it mechanically awkward - sure.

about three weeks ago
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NASA Tests Microwave Space Drive

queazocotal Re:Ugh (201 comments)

I read the actual abstract of the paper the article was based on. (the full text is not available)
'The tests were performed in a vacuum chamber, with the door closed, but at atmospheric pressure.'
Internal convection can move gas just fine and create anomalous torques.

about three weeks ago
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Microsoft Files Legal Action Against Samsung Over Android Patent Dispute

queazocotal Re: Laugh all the way to the bank (83 comments)

"Whether you think Microsoft's position is meritless or not, Samsung entered into a contract with them. They didn't ask a court for a legal opinion, they just stopped paying. You can't make unilateral decisions like that. "

Err - no.
In very rare circumstances do you ask a court to rule on a contract before anything has happened.
Their general response will be 'dismissed, you bear court costs, that's why you pay lawyers'.
The courts are in general not interested in offering legal advice - that's what you get expensive lawyers for.

This is exactly how contract law normally works.
X does something.
Y thinks they breached their contract, and consults their lawyers who agree that X breached the contract and has no right to future payment.
X says they diddn't, and their lawyers disagree.
Y stops paying.
X takes Y to court for non-payment.

Y cannot - at the first step - in most cases ask the court for an opinion.

about three weeks ago
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Microsoft Files Legal Action Against Samsung Over Android Patent Dispute

queazocotal Re:Laugh all the way to the bank (83 comments)

You can't really comment without seeing in full, the original agreement, and preferably scrutinising it in detail, along with any precedent in the relevant courts.

There could have, for example, been agreements as to Microsoft not doing some things in the phone space - such as for example selling android phones - that it's reasonable to argue (from Samsungs perspective) Microsoft has breached, voiding the original deal.

about three weeks ago
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NASA Tests Microwave Space Drive

queazocotal Re:Ugh (201 comments)

Nor were convection effects considered.
You don't need much airflow to generate 50 micronewtons.

about three weeks ago
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"BadUSB" Exploit Makes Devices Turn "Evil"

queazocotal Re:Not really that scary (205 comments)

In addition - fingerprinting the OS based on exactly how it probes for a USB device has been done, and is not particularly hard.
This can narrow down by a lot which OS you may be connected to - and have a dozen potential exploits based on the signature outcome.

about three weeks ago
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Nevada Construction Project Could Be Tesla/Panasonic Gigafactory

queazocotal Re:Build a what? (81 comments)

As I understand it - the aim is to make of the order of 10^9 - one billion - lithium cells a year.
That's enough cells to go in 200K small electric cars, or about 60K of the high capacity Tesla 85kWh packs.

about three weeks ago
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Long-range Electric Car World Speed Record Broken By Australian Students

queazocotal Re:This doesn't seem very extreme. (120 comments)

To a large extent, it's the small car vs large car problem.
Drag depends mostly on the frontal area.
Working out Cd*area for both cars.
http://ecomodder.com/wiki/inde... looks reasonable.
This gives Cd*area (ft^2) for the Leaf as 7,
https://en.wikipedia.org/wiki/... gives the Teslas as 6.1.
(Cd*ft^2)

The Tesla is - despite being a lot heavier and longer - not bigger in frontal area than the Leaf.
The Tesla is also marginally lower in absolute drag - making it 10% better in total drag or so.

This would lead to the conclusion that the 3.5* battery should give about 4* the range.
But, weight does matter a bit - there is extra drag in the tyres, which knock it back to 3.5*

about a month ago
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SLS Project Coming Up $400 Million Short

queazocotal Re:putting OP's bullshit into context (132 comments)

' when it will cost billions of dollars every time it flies, due to the high development costs, low flight rate, and standing army and facilities required to launch it.'
This is as I understand it a vile calumny on the SLS program.
Most realistic estimates say it's only going to cost one billion per launch, not several.

about a month ago
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Long-range Electric Car World Speed Record Broken By Australian Students

queazocotal Re:This doesn't seem very extreme. (120 comments)

Utter bullshit.
https://en.wikipedia.org/wiki/... - and several other sources I find say Australia is paying $(us).30/kWh or so.

That's one and a half kWh.

Or, 80 times more efficient than the Tesla. (which has an 80kWh battery pack, and doesn't quite make the range at 66mph)

If it's a skinny tyred wholly aerodynamic very small bicycle I might believe that - otherwise - LOL.

about a month ago
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Long-range Electric Car World Speed Record Broken By Australian Students

queazocotal This doesn't seem very extreme. (120 comments)

While perhaps to be taken with a pinch of salt - http://www.teslamotors.com/en_... - with the larger battery - at 65MPH claims to get 261 miles.
To get a Tesla to 350 miles needs an extra 30kWh of battery - about 120kg at the same performance as the existing battery.
This will easily fit in the trunk.

about a month ago
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Will Your Next Car Be Covered In Morphing Dimples?

queazocotal Re:Why not permanent? (138 comments)

I'm unsure - but suspect that if they were there permanently - with the profile done right, stamped out of the steel - they may improve stiffness, and reduce weight.
Stamping such a pattern would be 'interesting', and prone to lots of wear in the dies though.
For composite, in principle, it could almost be free.

about a month ago
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Ebola Outbreak Continues To Expand

queazocotal Re:Does it have Cold resistance level 2 (170 comments)

It's a virus, so has pretty good antibiotic resistance.

To follow on from the other comment.
You're faced with people who you've never seen, look quite different than you, and turn up in suits that cover their entire body.
This happens shortly after, or even before the community notices an issue - as they are surveying populations nearby.
Then people start dying, and these people who don't speak your language want to take the bodies of your loved ones, and desecrate them.

Add to this that education in these places is basically non-existant in many cases.
It's no wonder that people can come to the conclusion that the health workers are causing the disease.

Especially given the centuries long history of exploitation. Fake vaccination programs by the CIA to fine OBL haven't helped either.

about a month ago
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SpaceX Releases Video of Falcon Rocket's Splashdown

queazocotal Re:Getting good use out of commercial launch tests (49 comments)

'some middle manager will whine endlessly about this sort of experimentation.'

And will be sacked by the board.
Around 60% of the total cost of the rocket is the first stage.
The aim is to have this reusable in a few hours turnaround time.
If this works, savings per launch are tens of millions of dollars, even if it only works half the time.
If the second stage can be made reusable as well, going from $60M price to launch 10 tons to LEO to half of that _and_ making more profit per launch is quite possible.

about a month ago
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Buying New Commercial IT Hardware Isn't Always Worthwhile (Video)

queazocotal Re:Slashvertisement? (92 comments)

Sometimes.
A USB3 port, if you plug a USB3 hub into it, and 2 USB2 devices into it will go just as fast, and no faster than a USB2 hub.
Because that's what it is.
There are no transaction translators at all.
There are none even specced in the spec as optional, for high-end vendors to aspire to.

about 1 month ago

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