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Comment Partial solution: go 5 GHz (Score 2) 251

For the devices that support it (decent laptops, iPad, and possibly other tablets), going to the 5 GHz band is a huge win. There are plenty of non-overlapping channels, and congestion is lower. The problem is that most WiFi enabled phones only support the 2.4 GHz band, so this will not cover all cases.

Comment Re:How was this going to work? (Score 1) 410

Yes, I am aware of what is for sale, since we buy these things for our lab. (Although our sources are low enough in intensity to avoid the tracking required for the big boys.) I am confused by the use of the term "reactor" which is typically used to describe a device that is designed to produce fission reactions (or fusion, if you are a Farnsworth kind of person).

Generating fission is different than having a bunch of things that undergo radioactive decay. You need some neutrons, and a fissile material. It sounds like the (alpha, n) reaction on beryllium is a reasonable guess for neutron production, and you can use the neutrons to induce fission on uranium, even if it won't be remotely self-sustaining.

Comment How was this going to work? (Score 4, Insightful) 410

I'm puzzled how this guy was going to build a "nuclear reactor" out of mail-order isotopes and smoke detectors. Smoke detectors usually contain Am-241, which is an alpha emitter. The mail order stuff I assume was uranium ore. Was he planning to create neutrons from (alpha, n) reactions and use those to trigger a few fissions from the uranium?

This sounds like his experiment bears as much similarity to a reactor as a balloon full of hairspray resembles a car engine.

Comment Re:EC2/the cloud matters (Score 1) 212

Sure, being able to rent a computer for $1.68 an hour to do this cracking is a huge win. I was taking issue with the implication from the summary that this has been beyond individuals up until now, or that Tesla cards are some kind of magical supercomputer thing. We've had the power for a while, and high end GeForce cards can hold their own with Tesla on everything but double precision.

In fact, looking at the specs of the midrange NVIDIA GPU in my laptop, it could probably do this calculation in a few hours. Not as impressive as 6 minutes, but one should wary of breathless enthusiasm here.

Comment Re:Why use EC2? (Score 4, Interesting) 212

The assertion that high end Tesla cards (often $2k) are required for this crack is nonsense. In terms of integer, single precision floating point and memory bandwidth, a GTX 580 is actually FASTER than the most expensive Tesla card. Tesla cards have better QA for 24/7 usage, 4x faster double precision floating point, and 3 or 6 GB of memory, plus some other occasionally useful features. But anyone with an NVIDIA SLI gaming rig built in the last 2 years could easily have done what this guy did in less than 20 minutes.

Comment Re:tough choice (Score 3, Interesting) 264

The best choice is almost certainly to aim for the Pacific and evacuate all the coastal areas. The devastation from a mega-tsunami is far preferable (and more temporary) than the long-term climate disruption of a land collision. The amount of dust ejected into the air could easily trigger a "nuclear winter" kind of disaster.

Comment Re:So who's to the rescue? (Score 1) 432

Southwest has their quirks (poor boarding procedures for people with kids, some people really don't like open seating, etc), but they continue to allow each passenger two checked bags for free. They also don't charge explicit fees for ticket changes, though you have to pay the difference in seat prices if they have gone up. So far, they seem to be doing OK, so at least one airline hasn't had to go super-crazy with the unbundling to stay profitable. (Instead they just made their frequent flier awards much harder to use than 5 years ago.)

I think the only "extra charge" option is their Early Bird checkin, which basically gets you on the plane first for $10.

Comment Re:Who cares? (Score 4, Interesting) 356

Super-Kamiokande would light up like Christmas from a supernova only 600 light years from Earth. (Hopefully they still have a trigger configured to save such data, despite being used now as a target for the T2K experiment.) Super-K is 10x larger than Kamiokande-II and Kamiokande-II was able to detect 11 events from a supernova that was 250x further away than Betelgeuse. Granted, not all supernova have the same intensity, but still, I think we'd have a pretty good view from here.

Comment Re:That API looks fine to me (Score 1) 307

I assume they used the word "bucket," because that's what Amazon calls the same abstraction in S3. And that's really the target audience for this storage system: developers who are currently using Amazon S3 or are familiar with it. The idiot complaining about this API is angry that he went to a hardware store and didn't find the pipes already in the shape of his sprinkler system, possibly because he doesn't know what a hardware store is.

Comment Re:Above average developers are NOT GOOD (Score 1) 307

I tend to think of your taxonomy in terms of design outcomes:

4. Sufficiently engineered
3. Over-engineered
2. Under-engineered
1. Doesn't work or works on accident.

That is to say, average developers tend to nail the common case, but lack the experience or knowledge to spot the corner cases. Your "above average" developer wants to demonstrate his knowledge by optimizing for as many corner cases as possible at the expense of simplicity in the common case. The well-above average developer can balance the common and the exceptional.

Both over and under-engineered solutions are "bad," but the under-engineered solution usually has the advantage of less code to delete when you have to redesign everything. :)

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