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Comment Re:Biolite anyone (Score 1) 147

Biolite team has done extensive field test for their homestove, it really works (and rocks) for those people who do the daily cooking with wood stove.
And they use it to charge their cell phones and home light batteries, while saving on wood.

I use the summer camp smaller "geek" version of this stove, I'm happy with it even if it has some limitations the home version hasn't.

Comment Great USENIX study on SSD under power fault (Score 2) 512

Out of 15 SSD tested, only 2 are failure proof under power fault (only one maker and model).
(yes, I've read the pdf)

I'd like to know who is the winner, the anonymous vendor/model called "A-2".
It is not the most expensive, almost the cheapest, but it has at least a power-loss protection.
Another vendor has power-loss protection but his models failed the tests.

Direct link to pdf and figures erratum.

Bit Corruption: SSD#11, SSD#12, SSD#15
Flying Writes: none
ShornWrites: SSD#5, SSD#14, SSD#15
UnserializableWrites: SSD#2, SSD#4, SSD#7, SSD#8, SSD#9, SSD#11, SSD#12, SSD#13, HDD#1
Metadata Corruption: SSD#3
Dead Device: SSD#1
No failure: SSD#6, SSD#10, HDD#2

Their last word conclusion :

We recommend system builders either not use SSDs for important information that needs to be durable or that they test their actual SSD models carefully under actual power failures beforehand. Failure to do so risks massive data loss.

Thanks again for this link to the Usenix study, too bad you posted anon (patent need mod up).

Comment Not inner waves. Two actions at work. (Score 2) 43

This isn't inner waves, but water moving back and forth in a U shaped tank (water is pushed by compressed air on the tops of the U shape, alternatively).
So there's no wave at all in the tank.

I just wonder:

Is the counter-reaction mainly cause by the counter-weight of the water which fills only one side of the U tank, or by the momentum (acceleration) given to the water rolling in the tank ?
In either case, it could be more easily done with some solid weight on rails, with less energy lost (air compression and fluid displacement).

Comment Intent-aware OS and I/O bottleneck aware kernel (Score 4, Interesting) 226

If I copy huge files, while doing video processing, running a VM, and switching from one tab to another in the web browser, the system become quite unusable...
He could still be responsive with dynamic I/O priority handled by GUI and kernel.

What we lack most is some intention-aware GUI and OS kernel, working together so that the right process get the right priority and that I/O bottlenecks are handled gracefully.

Content creation activities are often I/O and CPU demanding, and even on creativity praised OS such as Mac OS we have this big problem of I/O channel unawareness.

One need to be able to start a huge file copy with a background intent so it will be throttled when the user starts a video effect preview which writes temporary files on one of the same disks of the copy.
The GUI gives the video preview higher priority, even on I/O, and the kernel detects the bottleneck on one of the disks and decide to almost freeze the file copy.
But then the user start the full video rendering in background, the GUI assigns the lower priority and the file copy resume to full I/O speed.

Comment Re:Cube is worst shape for cooling (Score 1) 197

Apple, in their next Mac, is considering a cylindrical tower, w/ an internal 3 plane cooling that cools everything.

Nice design, with the heat sink in the core like a funnel or chimney.
Its shape isn't compact, the cylinder is hollow, and this is not passive cooling :

"The form factor also echoes the shape of the single large fan located in the bottom of the machine." ref

Comment France might help too (Score 1) 211

France might help also. Areva has a lot of experience with nuclear reactors and wastes. They were willing to help during the meltdown, but at this moment Tepco seemed too proud to accept any help from the foreign countries.
They accepted later, as they bought some water filtering equipment to capture radionucleids.

Next time such a disaster occurs, I hope that the host country will not wait to aks help from the most competent companies in the world.

Submission + - Open Source Mapping Software Shows Every Traffic Death on Earth ( 2

cartechboy writes: Traffic deaths are set to outpace AIDS/HIV and malaria in the developing world, so the UN is trying to change that perception. This shocking open source, interactive map of crash data from the Pulitzer Center ought to help. Its grisly, but very informative. The mapping was produced by Pulitzer Center journalists using open source mapping technology from Mapbox. Compare the U.S. fatality rate of 11.4 per 100,000 to that of other nations, like the Dominican Republic, Iran, and Thailand and see how people were traveling when when killed (car, bicycle, etc).

Comment Switch to Pay What You Want (Score 2) 301

Some music groups have switched to Pay What You Want for a digital copy (mp3 download) of their album.
I bet they will have much more money than with any other distribution model.

For example, Psygnosis band started with this model, along with other merch and bonuses for those who want extra.

Even if I'm not a big fan, I paid a whooping 8€ for their album, digital copy, because I was happy to have it DRM free, and to be trusted by the band which feels confident that their listeners will pay a fair price.

All this money goes to the band, this is at least three times what they could get with physical sales.

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