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Comment Re:Summary (Score 1) 60

They give away Athlons for 10 bucks nowadays. If you could burn your custom asic into that, even if you wasted most of what used to be the Athlon; it would be fast as shit running your FPGA program natively. One you paid to lay it out, seems to me it might be cheap as shit to run a few thousand of them, and saturate the area with these detectors. Which feed already vastly condensed data that we would be capable of capturing.

That is just not how it works. You can't convert an athlon to a custom ASIC. The part that is the Athlon is the hardware.
To make a custom ASIC you need to make different hardware. That means making masks (cost a few million $), testing, making new masks, testing, running a batch, testing, testing testing.
With this batch size it isn't really interesting unless they need the additional speed ASICs bring.

Comment Re:Summary (Score 1) 60

FPGA's and CPUs are different enough that it is hard to compare the speed. For some tasks FPGA's are way faster, for most tasks CPU's are way faster.
Think of the FPGA as a hummer and the CPU as a Ferrari. Most driving is done on roads, where the Ferrari is faster. However, in rough country I would bet on the Hummer.

Take your final FPGA and burn chips from it (I know they do that). Run a hundred, and CERN might pay 20 grand a chip if they're good enough. I made that number up'; I don't have a clue, but that's where I'm going with my question.

Converting FPGA programming to chips means you need to invest millions to produce masks. You ain't gonna do that for a few hundred if you can avoid it.
Those chips are called ASICs. They are usually faster then the FPGA. And if you need many then they are cheaper.

Comment Re:Bikes lanes are nice (Score 1) 213

Since the cars drive 11 mph according to TFS the bikes are the fast ones. They have to limit their speed to match the slow cars.
The pedestrians are even slower than the cars so the speed delta is bigger for bike-pedestrian accidents.
Besides, dunno about the US but here the sidewalks are often paved with 30x30 cm (1 footx1 foot) concrete tiles. Those are unsuitable for bikes because they are just not flat enough.

'Round here (NL) better bike paths do usually increase speed for cars, because a percentage of drivers start biking. Then there are less cars on the road and thus less congestion.

Comment Re:containment (Score 1) 296

Still, that is approximately what happens.
Partial pressure put simply:
Forget absolute pressure. What matters in leaks is the pressure of each gas individually.
There is 0.00052% of He in the atmosphere. Assuming 1 bar of absolute pressure this means there is a partial pressure of 0.0000052 bar of helium in the atmosphere.
If the drive is filled with 1 bar absolute pure helium the difference will be 1-0.0000052 = 0.9999948 bar. That is the pressure that is important. There is no way the helium will not leak out. There is no such thing as a closed system. The system will also leak air in but far less. The result is a vacuum in the drive. In the end that vacuum will be filled with air but that takes far slower.

Now how long will the loss of helium take?

A 3,5 inch drive is about 0.3l. I assume that half of that is filled with hardware so I assume 0.15l He. A properly welded system without any connectors is probably in the range of 10^-12 mbar*l/s He leak tight. If I assume the drive will work at 0.5 bar helium we can take 10^12*500 mbar *0.3l = 150 * 10^12 seconds.
A year has 3.15 * 10^6 seconds. That is almost 5 million years. Not really something to worry about.
Yes there is a leak. Yes the helium will escape. No it doesn't matter because it just takes extremely long.

With a bad weld the time would drop significantly. However, the detection is easy. Helium leak detectors are commonplace, to detect minute leaks in high purity systems.

Sources:
Dimensions drive: Wikipedia.
Leak rate: I can get connectors to 10^-11 as standard items (Swagelok VCR full metal seal). Fully welded systems are probably better than that.

Comment Re:containment (Score 1) 296

When the helium is gone the drive will be high vacuum. The drive should include a breakaway disk (with shrapnel filter) to prevent collapsing of the enclosure. The system should detect that break and slow down the drive to 5400 RPM to fail gracefully.
SMART should report the pressure inside the drive and the status of the breakaway disk.

Then you can get the data off while the drive is in degraded mode.

Comment Re:Helium? (Score 1) 296

1. Generate all electricity from nuclear sources.
2. Store the alpha emitting waste in a capturing facility.
3. Wait for the alpha particles to encounter electrons (shouldn't take long)
4. Siphon the generated helium off.
5. Purify sufficiently.
6. ...
7. Profit.

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