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Comment Re:'10 times more efficient' and xenon gas (Score 4, Insightful) 52

It's all about delta-v, not about the occurence of said gasses on Earth.

Rockets work, whether we like it our not, according to the Tsiolkovsky rocket equation: the delta-v you can obtain it only logarithmic in your start mass / payload fraction, but linear in your exhaust velocity. That velocity is in ~3 km/s for chemical rockets, but 20-50 km/s for ion engines. That allows you to push a probe/ship from LEO into a transfer orbit using a massively lighter ship, which in turn allow you to launch that into orbit using a massively smaller launch vehicle.

Comment In Switzerland, they pretty much have to, by law (Score 5, Interesting) 545

In Switzerland (at least in my home Canton of Zurich), the children's way to school ("Schulweg") is pretty much sacred: Walking to school alone teaches the children to deal with the world around them, and it builds confidence. During the first year of Kindergarten you can bring them, but then they go alone.

When children live too far away from school, there is a bus service, but they make a point of letting the children off the bus some 1000ft from school, so that they still have their "Schulweg."

Comment Today's business class is the 70s' economy class (Score 5, Interesting) 819

Judging by images like these, today's business class is pretty much what economy class used to be in the 70s. Some argue that flying has become too cheap. I beg to disagree: flying in a humane manner has not become cheaper, it's just that you'd have to book business class nowadays.

Comment The only thing that may be leaked in addition... (Score 5, Informative) 56

... to what Tor already leaks, is the previous hop from which the exit traffic came, and possibly meta data on other tunnels relayed by (but not terminated at) the node. If the relayed connection is SSL/TLS encrypted, that encryption is end-to-end from the original client to the server; sniffing some exit-node memory does not help you there. If the related connection is in the plain, then, well, then sniffing the exit node's memory does not tell you any more than you already knew by looking at its plain-text traffic.

Now, Heartbleed is not completely harmless here: You may, if you're very lucky, be able to sniff the previous node name, but as Tor tunnels are longer than that, that does not help you much. Plus, tunnels endpoints tend to change every couple of minutes, making the cross section even smaller. Also, you may now be in a position to sniff data from nodes whose ISP network you do not control, allowing you to do network-wide attacks. That may in fact be the biggest problem.

Comment Good, but... (Score 3, Insightful) 254

... this should be in addition to good coding/style standards, proper design, proper source revision control, proper code reviews, and continuous testing/integration. Without any of the former, using this tool does not provide that much information: You first want to know whether your code does what you think it should do, whether it is thread safe, whether it is leaking memory, etc., etc., etc.

Comment A wish almost come true, but no ECC (Score 4, Interesting) 73

I agree with the power-consumption part, but the reason I would still not buy the Atom line is the simple fact that they do not support ECC RAM; when you say "reliability", you do want to know when your RAM walks out on you.

Supermicro sells a couple of mini-ITX board for mobile Core i7s, though, that will still allow you to build an under-30W-idle system with ECC RAM.

Comment Diffraction limited? (Score 5, Interesting) 204

Your average phone has a ~4 mm (diameter) lens. This yields an Airy disc of some 1.15 minutes of arc.

Even at a wide field of view (say, 60 degrees), this yields a maximum lateral resolution of some 3200 pixels. Isn't thus any camera with more than ~10 MPixels diffraction limited by the tiny lens, and not sensor limited?

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